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ACC JOURNAL XX 1/2014

Issue A

Natural Sciences and Technology

TECHNICKÁ UNIVERZITA V LIBERCI HOCHSCHULE ZITTAU/GÖRLITZ INTERNATIONALES HOCHSCHULINSTITUT ZITTAU UNIWERSYTET EKONOMICZNY WE WROCŁAWIU WYDZIAŁ EKONOMII, ZARZĄDZANIA I TURYSTYKI W JELENIEJ GÓRZE

© Technická univerzita v Liberci 2014 ISSN 1803-9782

ACC JOURNAL je mezinárodní vědecký časopis, jehož vydavatelem je Technická univerzita v Liberci. Na jeho tvorbě se podílí čtyři vysoké školy sdružené v Akademickém koordinačním středisku v Euroregionu Nisa (ACC). Ročně vycházejí zpravidla tři čísla. ACC JOURNAL je periodikum publikující původní recenzované vědecké práce, vědecké studie, příspěvky ke konferencím a výzkumným projektům. První číslo obsahuje příspěvky zaměřené na oblast přírodních věd a techniky, druhé číslo je zaměřeno na oblast ekonomie, třetí číslo pojednává o tématech ze společenských věd. ACC JOURNAL má charakter recenzovaného časopisu. Jeho vydání navazuje na sborník „Vědecká pojednání“, který vycházel v letech 1995-2008.

ACC JOURNAL is an international scientific journal. It is published by the Technical University of Liberec. Four universities united in the Academic Coordination Centre in the Euroregion Nisa participate in its production. There are usually three issues of the journal annually. ACC JOURNAL is a periodical publishing original reviewed scientific papers, scientific studies, papers presented at conferences, and findings of research projects. The first issue focuses on natural sciences and technology, the second issue deals with the science of economics, and the third issue contains findings from the area of social sciences. ACC JOURNAL is a reviewed one. It is building upon the tradition of the “Scientific Treatises” published between 1995 and 2008.

Hlavní recenzenti (major reviewers): Prof. Dr.-Ing. habil. Sybille Krzywinski

Technische Universität Dresden Institut of Textile Machinery and High Performance Material Technology Germany

Doc. PaedDr. Miroslav Kopecký, Ph.D.

Palacký University Olomouc Faculty of Education Department of Anthropology and Health Education Czech Republic

Contents Poly(Methyl Methacrylate-co-Methacrylic Acid) / N-Hexadecane Microcapsules to Impart Thermal Comfort ın Textıles ..................................................................................... 6 Ruhan Altun Anayurt; Alev Arslan; Derya Kahraman Döğüşcü; Cemil Alkan; Sennur Alay Aksoy Quality Aspects of Nonwoven Needle-Punched Polyester Filter Fabrics for Dust Control..................................................................................................................................... 14 R. P. Jamdagni; K. N. Chatterjee Assessing Garments Fit to Woman’s Body .......................................................................... 28 S. Jevšnik; Z. Stjepanovič; A. Rudolf; D. Grujić; T. Pilar Fabrication of Cross-linked Gelatin Electrospun Nanofibers Containing Rosemary Oil for Antibacterial Application ................................................................................................ 39 Nazife Korkmaz; Sena Demirbağ; M. Selda Tözüm; Sennur Alay Aksoy; Çağlar Sivri Impact of Material Parameters on Temperature Field within Clothing Laminates ....... 49 Ryszard Korycki; Halina Szafranska Textiles for Special Application ............................................................................................ 59 Doc. Dr. Ing. Dana Křemenáková; Prof. Ing. Jiří Militký CSc.; Jana Holovková 3D Images and Proportionality of the Human Body .......................................................... 69 Ing. Mgr. Marie Nejedlá, Ph.D. Studies on Compressibility of Woven Terry Fabrics .......................................................... 81 J. P. Singh; Rajesh Mishra; B. K. Behera List of Authors ........................................................................................................................ 93 List of Reviewers of ACC Journal ........................................................................................ 94 Guidelines for Contributors .................................................................................................. 99 Editorial Board ..................................................................................................................... 100

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POLY(METHYL METHACRYLATE-CO-METHACRYLIC ACID) / N-HEXADECANE MICROCAPSULES TO IMPART THERMAL COMFORT IN TEXTILES Ruhan Altun Anayurt1, Alev Arslan1, Derya Kahraman Döğüşcü1, Cemil Alkan1, Sennur Alay Aksoy2 1 Gaziosmanpaşa University, Faculty of Arts and Science, Department of Chemistry, Tokat, Turkey; 2 Süleyman Demirel University, Faculty of Engineering, Department of Textile Engineering, Isparta, Turkey 1 e-mail: [email protected] Abstract Thermal comfort using microencapsulated phase change materials (MPCMs) in innovative textile products and are widely investigated for their highly added value and processes related to microcapsule application to textiles are rapidly increasing to get the optimum performance. This study is focused on the preparation, characterization, and determination of thermal properties of microencapsulated n-hexadecane with poly(methyl methacrylate-co-methacrylic acid) (PMMA-co-MA) to be used in textiles with heat storage property. Introduction In recent years, the use of phase change material (PCM) for thermal energy storage has gained extensive attention owing to increasing energy consumption and environment pollution problems [1]. Phase-change materials (PCMs) have been used as thermal storage and control materials because of the heat absorption and release that occur upon a change of phase [2-4]. In 1987, the microencapsulation technology of PCMs was developed and incorporated with textile materials [5]. Currently, for garments and home furnishing products, microencapsulated PCMs are incorporated into acrylic fibers or polyurethane foams, or are embedded into a coating compound and topically applied to a fabric or foam [6]. Some researchers have tried to apply PCM technology to protective garments worn in extreme environments, from cold water to hot deserts [7, 8]. Fabrics with thermal regulating property are intelligent textiles having the property responding to external temperature changes. The thermal comfort property depends on the heat fluctuations in the range of the human body and the environment. Many efforts have been devoted to induce a thermoregulatory effect into textiles, for example the presence of microcapsules containing phase change materials (PCM) are added to textiles [9, 10]. The microencapsulation of PCMs involves enclosing them in thin and resilient polymer shells so that the PCMs can be changed from solid to liquid and back again within the shells [9]. Applications of PCM containing microcapsules into textiles include apparel, blankets, medical field, insulation, protective clothing and many others [11]. This study focused on the preparation, characterization, and determination of thermal properties of microencapsulated n-hexadecane with poly(methyl methacrylate-co-methacrylic acid) (PMMA-co-MA) to be used in textiles with heat storage property. n-Hexadecane corepoly(methylmethacrylate-co-methacrylic acid) (PMMA-co-MA) shell microcapsules were prepared with 1, 5, and 10% MA content to make the outer surface functional.

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1

Materials and Methods

1.1

Materials

n-Hexadecane (Fluka) was of analytical grade and used as received. Methyl methacrylate and methacrylic acid monomers (Merck) were used to synthesize co-polymer shell of microcapsule. Methyl methacrylate monomer was washed by NaOH before use. Ethylene glycol dimethacrylate was used as a cross-linker. Triton X-100 (Merck) was used as received. Ferrous sulfate heptahydrate and ammonium persulfate were also of analytical grade and used without further purification. 1.2

Microcapsule Preparation

Methyl methacrylate (100 g), methacrylic acid (1, 5, and 10 g in each of 3 different products), ethylene glycol dimethacrylate (10 g or 20 g), and n- Hexadecane (100 g) were assembled as oil phase in emulsion system in a total of 400 mL deionized water. Oil phase was emulsified using 10 g of Triton X-100 (surfactant). Suitable mixing speed was determined as 10000 rpm. The reaction mixture was homogenized at 50 °C using a mechanical homogenizer. Reaction was initiated by the addition of 1 g of ammonium persulphate (Na2S2O7) and 8 mL freshly prepared FeSO4 • 7H2O solution. Reaction medium was heated to 80 °C and maintained at that temperature for 30 minutes by stirring at 500 rpm. The reaction continued for five hours at the same temperature and stirring speed. The colloidal emulsion was concentrated by casting water and the precipitate was dried under vacuum at 40 °C. 1.3

Microcapsule Characterization

Thermal properties of microencapsulated PCMs were determined using a differential scanning calorimeter (DSC, Perkin-Elmer Jade) at the heating and cooling rate of 10 °Cmin-1 between – 5 °C and 80 °C under a constant stream of nitrogen at a flow rate of 60 mLmin -1. The spectroscopic analyses of the microcapsules were performed on KBr disks using a FT-IR instrument (Jasco 430) between 4000-400 cm-1. The particle sizes of microcapsules were measured using a particle sizer instrument (Malvern). Microcapsules were mixed in water at 10000 rpm to avoid clustering before testing. TGA was carried out on a thermal analyzer (PERKIN-ELMER TGA7). The TGA instrument was calibrated with calcium oxalate from 25 to 600 °C at a heating rate of 10 °Cmin-1 in a static air atmosphere. DTG was also obtained to determine maximum rate of weight loss. 2

Results and Discussion

DSC curves of poly(MMA-co-MA)/n-hexadecane-1 microcapsules were shown in Figure 1 and the data from the DSC analysis of poly(MMA-co-MA)/n-hexadecane microcapsules were given in Table 1. Thermal properties evaluated from the curves indicate that poly(MMA-coMA)/n-hexadecane-1 microcapsules melted at temperature range of 16.4−17.5 °C, crystallized at temperature range of 14.5−15.5 °C when pure n-hexadecane had a melting point of 18.2 °C and a crystallization point of 16.2 °C. The latent heats of melting and freezing of microcapsules were measured to be between 127.9−67.9 J/g and between – 69.3−129.7 J/g, respectively.

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Fig. 1: DSC curves of poly(MMA-co-MA)/n-hexadecane-1 microcapsules Tab. 1: DSC results of poly(MMA-co-MA)/n-hexadecane microcapsules Melting Melting Monomer Crystallization Crystallization Microcapsules Enthalpy Point constitution Enthalpy (J/g) Point (°C) (J/g) (°C) Poly(MMAco-MA)/n1 % MA 127.9 17.5 -129.7 15.5 hexadecane-1 Poly(MMAco-MA)/n5 % MA 76.9 16.9 -77.9 15.3 hexadecane-2 Poly(MMAco-MA)/n10 % MA 67.9 16.4 -69.3 14.5 hexadecane-3 Source: Own

The thermal stability of the microencapsulated PCMs was investigated using TGA. Figure 2 shows the TGA curves of Poly(MMA-co-MA)/n-hexadecane microcapsules and the degradation temperatures of microcapsules were tabulated in Table 2. Tab. 2: TGA data for PMMA/n-hexadecane microcapsules Degradation interval Microcapsules [°C] 80-175 (1 step) Poli(MMA-co-MA)/n- hexadecane -1 175-270 (2 step) 270-410 (3 step) 100-175 (1 step) Poli(MMA-co-MA)/n- hexadecane -2 175-275 (2 step) 275-410 (3 step) Source: Own

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Weight loss [%] 37 6 55 22 6 71

As it can be seen from the Figure 2 and Table 2 that poly(MMA-co-MA)/n-hexadecane-1 microcapsules degraded in three steps. The degradation of n-hexadecane started at 80 °C in Poly(MMA-co-MA) microcapsules while Poly(MMA-co-MA) shell degraded in two steps at 175 °C and 270 °C. Degradation processes were complete at around 410 °C in the microcapsules.

Source: Own

Fig. 2: TG curves of poly(MMA-co-MA)/n-hexadecane-1 microcapsules FT-IR analysis were used to prove the synthesis of microcapsules. For this reason the spectra of the ingredients and the microcapsules were given in Figure 3 and tabulated in the Table 3. The following remarks are from the FT-IR spectroscopy analysis; 

The peaks of C = O at 1741 cm-1 and 1698 cm-1 in the IR spectra of MMA and MA, respectively were overlapped and emerged at 1731 cm-1 in the microcapsules.



The peaks observed at 2923 cm-1, 2854 cm-1, and 1455-1388 cm-1 and 1241-1149 cm-1 ranges in IR spectra of microcapsules are characteristic peaks of paraffins. These peaks are proving the paraffin constitution in the microcapsules.



The peaks at 1631 cm-1 and 1635 cm-1 in the spectra of MA and MMA are – C = C – stretching peaks and they are invisible in the spectra of microcapsules. This result proved the synthesis of poly(MMA-co-MA) microcapsules.



According to the spectra of microcapsules, intensity of carbonly peaks at around 1440 cm-1 increases with the MA content and -OH stretching vibration band at 3400–3600 cm-1 becomes apparent.

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Fig. 3: FT-IR spectra of MA (a), MMA (b), n-hexadecane (c), poly(MMA-co-MA)/n hexadecane-1 microcapsules (d), poly(MMA-co-MA)/n hexadecane-1 microcapsules (e), poly(MMA-co-MA)/n hexadecane-1 microcapsules (f) Tab. 3: FT-IR data of poly(MMA-co-AA)/n-hexadecane microcapsules Frequency Materials Bond Functional groups (cm-1) Poly(MMA-co2923 and 2854 C-H stretch Paraffin MA)/n-hexadecane-1 1731 C=O stretch Esters and Carboxylic acid 1455 and 1388 C-H bend Paraffin 1241 and 1149 C-O stretch Esters Poly(MMA-co3400 and 3600 OH stretch Copolymer MA)/n-hexadecane-2 2923 and 2854 C-H stretch Paraffin 1729 C=O stretch Esters and Carboxylic acid 1452 and 1388 C-H bend Paraffin 1241, 1147 C-O stretch Esters

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Materials Poly(MMA-coMA)/n-hexadecane-3

Frequency (cm-1) 3400 and 3600 2923 and 2854 1729 1454 and 1386 1267,1241 and 1147

Bond

Functional groups

OH stretch C-H C=O C-H bend C-O stretch

Copolymer Paraffin Esters and Carboxylic acid Paraffin Esters

Source: Own

Figures 4, 5, and 6 present the particle diameter distributions of the prepared microcapsules. It is clear from the figures that the average particle sizes vary at different amounts of MA contents. The size of the poly(MMA-co-MA)/n-hexadecane-1 has a narrow distribution and the average particle size is 19.2 µm as shown in Figure 4 as it varies between 1–30 µm. When the amount of MA content is increased to 5% and then 10%, the average particle size of microcapsules goes to 14.77 and 24.51 µm, respectively. In the meantime, the particle size distributions are narrow as shown in Figures 5 and 6 as the particle size of Poly(MMA-coMA)/n-hexadecane-5 and Poly(MMA-co-MA)/n-hexadecane-10 varies between 1–20 µm, and 2–20 µm, respectively.

Source: Own

Fig. 4: %1 Poly(MMA-co-MA)/n-hexadecane microcapsules

Source: Own

Fig. 5: %5 Poly(MMA-co-MA)/n-hexadecane microcapsules

Source: Own

Fig. 6: %10 Poly(MMA-co-MA)/n-hexadecane microcapsules

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Conclusion Poly(MMA-co-MA) microcapsules containing n-hexadecane as a core material were produced for their functional surface to be exploited in textile applications. The microcapsules are capable of absorbing latent heats between 68 128 J/g during melting and releasing between – 69 and – 129 J/g during solidification. The data obtained from particle size analyzer instrument indicated that the mean particle sizes of microcapsules were ranged between 1 and 30 µm, which were suitably narrow for the applications. The synthesis, presence of n-hexadecane, and reactive groups in the microcapsules were proven by FT-IR spectroscopy analysis. The phase change temperatures of the poly(MMA-co-MA)/nhexadecane microcapsules prepared were very close to that of n-hexadecane. Three types of PMMA/n-hexadecane microcapsules with suitable phase change temperatures and considerably high enthalpy were produced to be used as thermal comfort additives in textiles. The reactive surface of the microcapsules was bound to textiles easily due to electrolytic interactions, or reacted to textiles by chemical means. Acknowledgements The authors would like to acknowledge the financial support of the Scientific and Technical Research Council of Turkey (Project no.: 111M484). Literature [1]

SARI, A.; ALKAN, C.; KARAIPEKLI, A.: Applied Energy, 87, 1529, 2010.

[2]

SHIN, Y.; YOO, D.; SON, K.: Journal of Applied Polymer Science, 97, 3, 910, 5, 2005.

[3]

MULLIGAN, J. C.; COLVIN, D. P.; BRYANT, Y. G.: J Space Rockets, 33, 278, 1996.

[4]

COLVIN, D. P.; MULLIGAN, J. C.: US Patent, 4, 911, 232, 1990.

[5]

BRYANT, Y. G.; COLVIN, D. P.: Techtextil-Symposium, 3, 1, 1992.

[6]

PAUSE, B. H.: J Ind Fabrics, 33, 93, 2003.

[7]

COLVIN, D. P.; BRYANT, Y. G.: HTD Am Soc Mech Eng, 362, 123, 1998.

[8]

COLVIN, D. P.; HAYES, L. J.; BRYANT, Y. G.; MYERS, D. R.: Heat Transfer Division, Am Soc Mech Eng, 268, 73, 1993.

[9]

SÁNCHEZ, P.; SÁNCHEZ-FERNANDEZ, M. V.; ROMERO, A.; JUAN RODRÍGUEZ, F.; LUZ SÁNCHEZ-SILVA: Thermochimica Acta, 498, 16, 2010.

[10] BRYANT, Y.G.; COLVIN, D.P.: Fiber with reversible enhanced thermal storage properties and fabrics made therefrom, US Patent, 4, 756, 958, 1988. [11] SHIN, Y.; YOO, D.I.; SON K.: J. Appl. Polym. Sci. 96, 2005.

Ruhan Altun Anayurt; Alev Arslan; Derya Kahraman Döğüşcü; Cemil Alkan; Sennur Alay Aksoy 12

MIKROKAPSLE POLY(METHYLMETHAKRYLÁT – KOPOLYMER) / KYSELINY N-HEXADEKANOVÉ PRO TEPELNÝ KOMFORT TEXTILIÍ Tepelný komfort získaný pomocí mikrokapsulovaných materiálů se změnou fází (MPCMs) u inovačních textilních výrobků je široce zkoumán pro svou vysokou přidanou hodnotou, a procesy spojené s aplikací mikrokapslí na textilie se rapidně zrychlují ve snaze dosáhnout optimálního výkonu. Tato studie se zaměřila na přípravu, charakterizaci a stanovení tepelných vlastností mikrokapslí kyseliny n-hexadekanové s poly (methyl -methakrylátkomethakrylovou kyselinou) (PMMA-co-MA), které mohou být využity u textilních výrobků s tepelně izolačními vlastnostmi.

POLYMETHYLMETHACRYLAT-MIKROKAPSELN ZUR GEWÄHRLEISTUNG VON WÄRMEKOMFORT IN TEXTILIEN Der Wärmekomfort, wie er mit Hilfe von Mikrokapselmaterialien bei Änderung der Phasen (MPCMs) bei innovativen textilen Erzeugnissen gewonnen wird, wird wegen seines hohen Zugabewertes gründlich erforscht. Die Prozesse, die mit der Anwendung von Mikrokapseln an Textilien verbunden sind, beschleunigen sich rapide bei der Bemühung, optimale Leistung zu erreichen. Diese Studie konzentriert sich auf die Aufbereitung, Charakterisierung und die Festlegung von Wärmeeigenschaften der Mikrokapseln der Säure n-HexadekanPolymethylmethacrylat-Komethakryl-Säure (PMMA-co-MA), die bei Textilprodukten mit isolierenden Eigenschaften genutzt werden können.

MIKROKAPSUŁKI Z KWASU N-HEKSADEKANOWEGO Z POLIMETAKRYLANEM METYLU – KOPOLIMEREM DO KOMFORTU CIEPLNEGO TKANIN Komfort cieplny uzyskany przy pomocy materiałów mikrokapsułowanych ze zmienioną fazą (MPCMs) w innowacyjnych produktach tekstylnych jest przedmiotem szeroko zakrojonych badań ze względu na wysoką wartość dodaną. Coraz bardziej do tkanin stosowana jest także technologia mikrokapsułowania, co ma na celu osiągnięcie optymalnej wydajności. Niniejsze opracowanie dotyczy przygotowania, scharakteryzowania i określenia właściwości cieplnych mikrokapsułek kwasu n-heksadekanowego z polimetakrylanem metylu-kopolimerem (PMMA-co-MA), które mogą być wykorzystane w produktach tekstylnych o właściwościach termoizolacyjnych.

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QUALITY ASPECTS OF NONWOVEN NEEDLE-PUNCHED POLYESTER FILTER FABRICS FOR DUST CONTROL R. P. Jamdagni1; K. N. Chatterjee The Technological Institute of Textile and Sciences, Bhiwani, Haryana, India e-mail: [email protected] Abstract Needle-punched non-woven filter fabrics made of polyester fibres have been studied for dust filtration by measuring the filtration properties on a fabricated filtration apparatus. The effect of fabric gsm, needle density and needle penetration on filtration characteristics has been studied. The fabrics with higher gsm show higher filtration efficiency and collection capacity but at the cost of increased pressure drop. With the increased needle density and needle penetration value, the filtration properties improved initially up to a certain extent and thereafter reduction takes place. Introduction Over the last decades, the environmental issue has become a major subject, affecting science and technology of the entire world due to serious environmental impacts caused by air pollution. Environmental pollution has negative influences on human health, ecological systems, the greenhouse effect and the ozone layer depletion, etc. Filtration plays a critical role in our day-to-day life by providing healthier and cleaner products and environment. Textile materials are used in the filtration of air, liquids, food particles and industrial production. Filter fabrics are used widely in vacuum cleaners, power stations, petrochemical plants, cement plants, etc. Textile materials, particularly woven and nonwoven filter fabrics, are suitable for filtration because of their complicated structure and thickness, dust particles have to follow a tortuous path around textile fibres. The choice of material to be used in filters is often the most important factor that must be considered if optimum performance is desired. The filter medium should be selected primarily for its capability to retain the solids that must be separated from the fluid, with an acceptable length of life. The filtration conditions (whether involving hot acids, extreme heat, etc.) and the type of filtration (whether gas or liquid) are also important considerations. Both woven and non-woven fabrics are used for filtration purposes but non-woven fabrics are preferred to woven fabrics for improved performance in case of air filtration. Among the non-woven, the needle-punched filter fabrics are the fastest growing of all types of filter media. Many researchers have carried out extensive work on filtration and mechanical properties of filter fabrics which are governed by many factors [1-8]. Fibre length and fibre fineness plays an important role in filtration and mechanical characteristics of filter fabrics. In order to secure high strength to the needled fabric, it is necessary to use long fibres. Finer fibres will yield greater strength to the fabric provided that the fibre damage is avoided1. The permeability and hence the filtration properties are greatly influenced by the fibre fineness. If fabric weight and density are kept constant, air-permeability varies linearly with the fibre diameter and hence fineness. When a very dilute aerosol of submicron particles are filtered, the capture efficiency varies linearly with d/s, where d is the effective particle diameter and s is the inter-fibre spacing. A decrease in fibre linear density at constant fabric weight results in an increase in both capture efficiency and pressure drop [2]. At higher needling densities, the fabric weight decreases with increasing depths of needle penetration [7]. Increase in needle penetration also leads to decreased thickness of the fabric. 14

The above changes in fabric weight and thickness cause the fabric density increase with an increase in needle penetration. Filtration efficiency depends on needle dimension and needle density as these cause more opening for dust to flow through. Filter having higher permeability will have less resistance compared with filters having lower permeability and so will collect more dust. The objectives of the present study were to prepare a range of nonwoven needle-punched filter fabrics and study their quality aspects in terms of filtration properties. 

To fabricate an instrument for measuring the filtration parameters i.e., filtration efficiency, air permeability, pressure drop, etc.



To optimize fabric and needle parameters i.e., gsm, needling density and needle penetration on the filtration properties of nonwoven needle-punched filter fabrics using factorial design techniques.

1

Designing a filtration apparatus

It is often difficult to study the filtration performance primarily because the emission processes in surface filter media are transient in nature. Further, there are difficulties in developing standard test apparatus simulating the practical situation as design of filter unit, and aerosol characteristics vary widely even in the same application at different places. The standard testing of filters and filter media is important for the design and development, manufacturing and selection of filter media, as well as for quality assurance during the production process. Particle-size dependent filtration efficiency, differential pressure drop, dust loading capacity, and life of the filter media are the most required parameters for filter material characterization. 1.1

Description of fabricated filtration apparatus at TITS

It consists of a compressor line, dust feeder, filter cloth holder, absolute filter, orifice meter, and suction pump, as well as digital timer and solenoid valve for controlling filtration and cleaning cycles of filter fabrics. 1.2

Measurement of filtration efficiency and pressure drop by the fabricated apparatus

Filtration efficiency and pressure drop of the samples were measured in the experimental setup. Filtration efficiency is defined as a ratio of amount of dust collected by the fabric to the amount of dust fed expressed as a percentage. (1) Cement dust having a particle size range of 3.89 microns to 118 microns was used. The actual pressure drop ΔP was calculated in the following way: ΔP = P1 – P2,

(2)

where P1 = Pressure drop across the filter holder with fabric placed in proper position and P2 = Pressure drop across the empty fabric holder.

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Fig. 1: Device for dust generation 2

Materials and methods

Twenty nonwoven needle-punched fabric samples were prepared from 100% polyester fiber of 3.0 denier and staple length of 5l mm., with varying constructional parameters viz., Fabric Weight (gsm), Needling Density (punches/ sq.cm), Needle Penetration (mm). The values of different variables were chosen according to the “Factorial Design of Experiments” (Table 1). The fabrics were made from parallel laid web which was obtained by feeding opened fibers in the “DILO” Laboratory model card. The carded web was fed to “DILO” Needle loom type OD -II/6. Experiments were conducted with dust free air to estimate the effect of variables on the permeability. The physical properties of the fabrics made were measured. The results of the experiment on permeability and physical properties are given in Table 1. Experiments were also conducted to estimate filtration efficiency and pressure drop by using cement dust. Table 1 gives the experimental values of filtration efficiency and pressure drop.

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Tab. 1: Coded and Actual Levels of Fabric Weight, Needling Penetration Levels of variables X1 X2 Sl. CODED ACTUAL CODED ACTUAL no LEVEL LEVEL LEVEL LEVEL 1 -1.000 300 -1.000 300 2 +1.000 500 -1.000 300 3 -1.000 300 +1.000 500 4 +1.000 500 +1.000 500 5 -1.000 300 -1.000 300 6 +1.000 500 -1.000 300 7 -1.000 300 +1.000 500 8 +1.000 500 +1.000 500 9 -1.682 232 0.000 400 10 +1.682 568 0.000 400 11 0.000 400 -1.682 232 12 0.000 400 +1.682 568 13 0.000 400 0.000 400 14 0.000 400 0.000 400 15 0.000 400 0.000 400 16 0.000 400 0.000 400 17 0.000 400 0.000 400 18 0.000 400 0.000 400 19 0.000 400 0.000 400 20 0.000 400 0.000 400

Density and Depth of Needle

X3 CODED

ACTUAL

LEVEL

LEVEL

-1.000 -1.000 -1.000 -1.000 +1.000 +1.000 +1.000 +1.000 0.000 0.000 0.000 0.000 -1.682 +1.682 0.000 0.000 0.000 0.000 0.000 0.000

8 8 8 8 14 14 14 14 11 11 11 11 6 16 11 11 11 11 11 11

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3

Experimental analysis

The results of all the responses for the various experimental combinations were fed to a computer. Suitable computer program (SYSTAT) was used for calculating the regression coefficients. The response surface equations for different fabric characteristics along with the correlation coefficients between the experimental values and the calculated ones obtained from the response surface equations are given in Table 2.

17

Source: Own

Fig. 2: Effect of FW and ND on THK Tab. 2: Thickness, Density, Porosity, Air permeability and Sectional permeability Fab. Actual Fabric Fabric Porosity Air Sectional Air Ref.no fabric Thickness Density (%) Permeability Permeability weight (mm) (gms/cc) (cc/sq.cm/sec) (cc/cm/sec) (gsm) F1 311.96 4.324 0.0721 94.78 65.90 28.49 F2 508.57 5.158 0.0986 92.86 43.43 22.40 F3 315.93 3.910 0.0808 94.14 58.96 23.05 F4 524.35 5.254 0.0998 92.77 36.87 19.37 F5 276.13 2.746 0.1005 92.72 54.66 15.00 F6 497.88 3.824 0.1302 90.56 28.82 11.02 F7 278.99 2.936 0.0950 93.12 50.97 14.96 F8 492.85 3.314 0.1487 89.22 22.46 7.44 F9 247.35 2.486 0.0995 92.79 50.74 12.61 F10 607.45 4.742 0.1281 90.72 22.94 10.88 F11 377.66 3.914 0.0965 93.00 40.65 15.91 F12 381.54 3.450 0.0991 92.82 30.98 10.69 F13 453.70 4.844 0.1106 91.98 46.39 22.47 F14 371.28 3.198 0.1161 91.59 28.56 9.13 F15 412.86 3.584 0.1152 91.65 36.85 13.21 F16 404.63 3.628 0.1115 91.92 34.73 12.60 F17 398.71 3.626 0.1099 92.04 34.56 12.53 F18 406.48 3.702 0.1098 92.04 32.76 12.13 F19 404.87 3.596 0.1126 91.84 37.24 13.39 F20 401.32 3.664 0.1095 92.07 35.87 13.14 Source: Own

With the help of regression coefficients, the canonic surface plots were developed by using SYSTAT package. The plot of fabric weight (FW) and needle density (ND) on fabric 18

thickness. Figures show the results of fabric density for the two independent variables at a time, i.e., FW & ND, FW & NP and ND & NP respectively. 3.1

Air Permeability

Air permeability was measured by the instrument developed in the laboratory. The reading was taken for 10 mm-WG pressure drop across the fabric and air permeability values were calculated in cc/sq.cm/sec from the calibration curve and the area of the fabric. The permeability data and conditions of the variables given in Table 1 are processed in software ‘SYSTAT’ for regression analysis. The coefficients of the regression analysis obtained are given in equation (3). (3)

Source: Own

Fig. 3: Effect of FW and NP on SAP

19

Source: Own

Fig. 4: Effect of ND and NP on SAP The coefficients of the equation 6.1 are used to develop canonic surface plots. Figures show the effect of FW & ND, FW & NP and ND & NP on air permeability values. Similarly, the equation gives the obtained values of regression coefficients of sectional permeability (4). (4) 3.1.1

Effect of Fabric Weight & Needle Density

Figures show the effect of fabric weight (FW) and needle density (ND) on the air permeability & sectional air permeability of the fabrics at constant level of needle penetration (11 mm). It can be observed from the Figures that at any level of needle density when the fabric weight is increased the permeability decreases. From the figures, further observations can be made. With the increase of needle density at various level of fabric weights, the permeability first decreases and then rises. The effect is more pronounced at higher level of fabric weights. The decreasing trend of permeability is observed around 500 punches/sq.cm. The decrease in air permeability with the increase in fabric weight can be ascribed to the higher total surface area with the higher gsm. Fabric thickness & fabric density also increases with the increase in fabric weight as can be seen from the Figures. The decreasing trend of air permeability with the fabric weight may be due to the more resistance offered by thicker & denser fabric. The initial decrease of permeability with the increase of needling density may be ascribed to the fact that increased needling density increases the compactness of the fabric, i.e., the density of the fabric is increased (as evident from the Figure), resulting in more resistance to air flow and hence reducing the air permeability. However, at higher level of needling density (in this case after 500 punches/sq.cm), the air permeability increases with the increase in needling density. This may be due to the fact that at higher level of needling 20

density, any further increase in needling density ensuring the number of pegs to be greater which ultimately results in higher air permeability. From the above study, it may be concluded that with the help of contour curves various definite permeability values can be obtained by different combinations of gsm & punches/sq.cm. Optimum values of permeability can be chosen either by selecting higher gsm and lower punches/ sq.cm or by selecting lower gsm with higher punches/sq.cm from various combinations. For example, 600 gsm with 300 punches/sq.cm can be chosen to get 14 sectional permeability values. However, similar values can be obtained from 320 gsm (approx.) with 500 punches/sq.cm. It is preferable to produce filter fabrics with 600 gsm with 300 punches/sq.cm to obtain 14 cc/cm/sec sectional permeability value, as because higher gsm (600) will produce durable fabric and by lowering punches/sq.cm (300), the productivity will be higher as well as less chance of damages of nonwoven structure as compared to the fabric with 320 gsm and 500 punches/sq.cm. Moreover, from the above curves, permeability values at same gsm with varying punches/sq.cm or vice-versa can be obtained. Therefore, 600 gsm with 400 punches/sq.cm can be chosen to obtain 11 cc/cm/sec sectional permeability values instead of 600 gsm with 600 punches/sq.cm for the same reason as explained earlier that more is the punches/sq.cm, more will be chances of breakage of fibers and hence the durability of nonwoven structure will be reduced. 3.1.2

Effect of Fabric Weight & Needle Penetration

The effect of fabric weight (FW) and needle penetration (NP) on the permeability values at constant needle density (400 punches/sq.cm) are shown in Figures. It can be seen from the Figures that both permeability values are decreased with the increase of fabric weight at all levels of needle penetration. However, with the increase of needle penetration at all levels of fabric gsm the permeability values are found to be reduced up to certain extent (14-16 mm) and thereafter increases. The reason for the decreasing trend of permeability with the increase in fabric weight is that the higher the gsm, the higher is the total fiber surface area restricting the air flow. Another probable reason is that with the increase of gsm, the thickness of the fabric increases and the thicker is the fabric, the lower is the air flow. Further, the increase in fabric weight resulted in dense fabric (as may be evident from the fabric density results and the denser is the fabric, the bigger is the air drag and hence lesser is the air flow. The decrease in permeability with the initial increase in needle penetration may be due to the fact that with the increase in needle penetration more number of fibers will be caught by the barbs resulting in better interlocking of fibers, which in mm will cause higher fabric compactness. The increased compactness of the fabrics offers more resistance to air flow and so the permeability of the fabric reduces. Though, at lower fabric weight the air permeability value does not change much after 12-14 mm penetration, however, after 16-18 mm penetration increasing trend has been observed. With the increase in needle penetration, the change of fiber arrangement along the direction of air flow resulting reduced air drag. This may be predominating over the effect of fabric density. At much higher needle penetration the number of fibers which break becomes high and so the size of the pegs becomes larger. This causes the air permeability values of the fabric to increase. From the above study it may be concluded that for obtaining certain permeability values optimum level of fabric weight (gsm) and needle penetration can be chosen. For example, it will be useful in providing various ranges of fabric weight (400-600 gsm) and needle penetration (12-18 mm) to obtain sectional permeability value as 10 cc/cm/sec. 600 gsm with

21

12 mm penetration should be used to get the above mentioned permeability value in order to achieve better filter life and less chances of fiber breakages. 3.1.3

Effect of needle density & needle penetration

Figures depict the effect of needle density (ND) and the depth of needle penetration (NP) on the air permeability and sectional air permeability values at constant fabric weight (400 gsm). When air permeability decreases, the increase in either needling density or needle penetration up to a certain limit may be seen, but at higher levels of needling density (450-500 punches/sq.cm) and needle penetration (14-16 mm) the air permeability of the fabric rises. The decreasing trend of permeability at the initial stages of needle intensifies, probably due to the consolidation of web structures resulted in dense fabric, which may be evident. However, after a certain limit of needle intensities, any further increase of either needle density (i.e., after 450-500 punches/sq.cm) or needle penetration (after 14-16 mm) the permeability values are found to be increased mainly because of peg formation. The channels created in the fabric due to the passage of needle are considered to be one of the main reasons for the rise in air permeability. The fiber breakages may again be attributed to the above phenomenon. From the above study, it may be concluded that the contour curves will be helpful in getting a series of combinations of penetration & needle density values for a definite permeability. Moreover, the values of penetration up to 14 mm & punches/sq.cm values up to 450 can be chosen so that fiber breakages do not take place. 3.2

Filtration properties

Filtration properties in terms of filtration efficiency and pressure drop were measured. Table 3 gives the values of filtration efficiency and pressure drop values after one minute of filtration time. The filtration efficiency & pressure drop data and conditions of the variables given in Table 6.3 are processed in software 'SYSTAT' for regression analysis. The coefficients of the regression analysis obtained is given in equation 5.

(5)

22

Tab. 3: Filtration Efficiency, Pressure drop, Collection capacity, Dust weight Sample No. Filtration Pressure Drop Collection Dust weight Efficiency Capacity (abs. Filter) [%] [mm] [mg /sq.cm] [mg] F1 96.98 13 48.75 10.97 F2 98.95 18 53.69 7.45 F3 97.12 14 49.65 9.46 F4 99.23 21 64.53 6.49 F5 97.32 15 49.70 9.20 F6 99.48 26 55.18 5.99 F7 97.46 16 50.44 8.92 F8 99.98 28 56.52 5.12 F9 97.99 17 52.07 8.39 F10 99.50 25 55.56 5.22 F11 98.71 18 52.57 7.86 F12 99.13 20 53.78 6.78 F13 97.86 16 51.13 8.59 F14 99.26 21 54.72 7.27 F15 99.28 21 57.24 9.94 F16 98.73 20 56.92 10.18 F17 99.08 21 52.38 9.04 F18 99.36 22 55.87 9.56 F19 99.42 23 55.82 10.26 F20 99.30 22 54.75 9.20 Source: Own

3.2.1

Effect of fabric weight and needle penetration

The results of filtration efficiency with the increase of gsm (FW) and needle penetration (NP) are shown at constant needle density (400 punches/ sq.cm). Filtration efficiency is found to be increased with the increase of gsm at all levels of needle penetration. With the increase of needle penetration, the filtration efficiency first increases and thereafter decreases at all levels of gsm. The reasons for increasing the filtration efficiency with the increase in fabric weight are already explained. The initial increase of filtration efficiency with the increase of penetration may be due to the fiber to fiber interlocking within the web structure and hence compactness of the fabric increases. However, after a certain limit, any further increase of penetration may create peg holes through which dust particles may escape, causing reduced filtration efficiency. From the above study, the conclusions can be drawn that it may be useful in selecting various combinations of fabric weight and needle penetration values for obtaining maximum filtration efficiency. For example, 500-600 gsm with 10 mm penetration may be selected in obtaining more than 100 % filtration efficiency after t minute of filtration time. 3.2.2

Effect of needle density and needle penetration

The effect of needle density (ND) and needle penetration (NP) on the filtration efficiency is shown. It may also be seen that with the increase in either needling density or needle penetration, the filtration efficiency increases firstly up to a certain level and then falls. 23

The reasons for the above mentioned trends have been discussed earlier: that better fiber to fiber interlocking and mass consolidation is taking place with the increase in needle density, thus ultimately producing a dense fabric on which dust particles can be easily adhered due to surface filtration mechanism and therefore showing higher filtration efficiency. However, after a certain limit, in this case 400-450 punches, the reverse trend is observed i.e., with the further increase in needle intensity in the form of punches/sq.cm, no more consolidation is taking place, on the other hand peg-hole formation and fiber breakages may occur and thus lowering the filtration efficiency. With the initial increase in the depth of penetration, the density of the fabric increases and hence filtration efficiency also increases. On the other hand, after a certain depth of needle penetration, the filtration efficiency drops. In practice, the fibers in the pegs lie in a parallel direction to the gas flow during filtration & thus do not form a good barrier to the passage of small dust particles. The increase in the depth of needle penetration will effectively increase the size of the pegs, which in mm would cause reduction in filtration efficiency. The results are in accordance with the findings of Igwe [2, 6, 21] and Igwe and Smith [10, 11, 20]. From the above study it may be concluded that both the needle density & needle penetration values can be selected according to optimum requirements of filtration efficiency. For example, 400-450 punches/sq.cm with 12 mm penetration can be useful in obtaining more than 99.4 % filtration efficiency after 1 minute of filtration time. 3.3

Pressure drop

Pressure drop (mm-WG) was measured after 1 minute of filtration time from the readings of manometer across the fabric. The manometer reading across the orifice was maintained constant at 2 cm-WG so as to maintain constant face velocity as 30 cm/sec. 3.3.1

Effect of fabric weight & needling density

It is observed that the increase in fabric weight shows higher pressure drop at all levels of needle densities. As observed, the pressure drop of the fabrics first increases with needling density & then it falls. The above phenomenon can be explained as due to the fact that with the increase in fabric weight total fabric surface area increases. Another reason which may attribute to higher pressure drop are fabric thickness & density. The increase in fabric surface area will be able to restrict the air flow and thus causing more air drag. Again, increased fabric density rises air resistance which in turn enables retention of a higher quantity of dust particles but at the same time increases the pressure drop as observed. The rise in pressure can be attributed to the fact that the initial increased needling density leads to an increased entanglement of fibers within the fabric which increases the density & hence it offers more resistance to flow. The fall in pressure drop is ascribed to the decrease in density due to higher needling action. Hence, the resistance to flow decreases with the further increase in needle density. It will be helpful in selecting the ranges of fabric weight and needle density values to obtain minimum values of pressure drop. Lower pressure drop level (10 mm-WG) may be obtained by using 200 gsm with 200 punches/sq.cm and 600 punches/sq.cm. 200 gsm with 200 punches/sq.cm should be selected for higher productivity and less chance of breakages. However, from the filtration efficiency studies, 500 gsm is preferable with 400 punches/sq.cm, it depicts that with 400 punches/sq.cm, maximum pressure drop values obtained as 27 mm-WG for 600 gsm fabric. One can conclude from the above studies that less pressure drop (22 mm-WG) can be obtained for 500 gsm with 300 punches/sq.cm or similar pressure drop level (22 mm-WG) can be obtained with 600 punches/ sq.cm for 500 gsm fabric 24

weight. Hence, 500 gsm with 300 punches/sq.cm or 500 gsm with 400 punches/sq.cm can be selected to obtain higher filtration efficiency with acceptable pressure limit (22 -24 mm WG). 3.3.2

Effect of fabric weight and needle penetration

The plot of pressure drop with the variation of fabric weight (FW) and Needle Penetration (NP) at constant Needle Density (400 punhces/sq.cm) is shown. The pressure drop results are found to be increased with the increase of gsm at all level of penetration. However, at higher penetration range (14-18 mm) more pronounced effect is observed. With the increase of penetration, at higher gsm level (500-600), the pressure drop is found to be increased. However, at lower level of gsm the pressure drop first increases and thereafter decreases with the increase of penetration. With the higher gsm, dense fabric causes lower air flow which results in higher air drag. At higher gsm, the fabric thickness increases and hence, with the increase of penetration more barbs will actuate for fiber locking and therefore better consolidation of web structure takes place resulting in dense fabric. The denser is the fabric, the lower is the air flow causing more pressure difference. On the other hand, at lower gsm, the fabric thickness is reduced, thus fiber ruptures as well as creation of channels may take place with the increase of penetration. Conclusion The results of the study will be beneficial in optimizing pressure drop values for various combinations of gsm & needle penetration. Though lower pressure drop values are obtained for 200 gsm with 20 mm penetration, it is not advisable, however, because higher penetration values may cause more fiber breakages. As mentioned above, 500-600 gsm will be useful in obtaining higher filtration values. Therefore, from the above work it may be concluded that with the 500-600 gsm with 8-10 mm penetration would give acceptable pressure drop limit (20-24 mm-WG). The predicted equations for various responses agree well with the experimental data, as can be seen by the high coefficient of multiple correlations. Furter conclusions might be drawn later from the ongoing research. Literature [1]

LAMB, G. E. R.; COSTANZA, P.; MILLER, B.: Text. Res. J., 45, No. 6, (1975) p. 452.

[2]

IGWE, G. J. I.: Text. Res. J., 58, No. 5, (1988) p. 280.

[3]

SAYERS, I. C.; BARLOW, G.: Filtration and Separation, No. 5, Sept-Oct, (1974) p1.

[4]

RODMAN, C. A.: Filtration and Separation, Nov-Dec, (1980) p. 137.

[5]

ROTHWELL, E.: Filtration and Separation, No. 15, Nov-Dec., (1983) p. 586.

[6]

IGWE, G. J. I.: Surface structure of Needle felted gas filter: – Microscopical examination technique, Ellis Horwood Series in Chemical Engineering, (1988) p. 69.

[7]

SIEVERT, J.; LOEFFIER, F.: Filtration and Separation, Nov-Dec (1987) p. 261.

[8]

DIETRICH, H.: Filtration and Separation, No. 9, (1972) p. 438.

[9]

ROTHWELL, E.: Filtration and Separation, No. 9, Nov-Dec., (1976) p. 477.

[10] IGWE, G. J. I.; SMITH, P. A.: Melliand Textilber, 5, (1986) p. 327 and (1986) E146. [11] IGWE, G. J. I.; SMITH, P. A.: J. Text. Inst. No. 4, (1986) p. 263. [12] ATWAL, S.: Text. Res. J., 75, No. 10, (1987) p. 574. 25

[13] LAMB, G. E. R.; COSTANZA, P. A.: Text. Res. J., 49, No.2 (1979) p. 79. [14] KOTHARI, V. K.; NEWTON, A.: J. Text. Inst., 65, (1974) p. 525. [15] DENT, R. W.: J. Text. Inst., 67, No.6, (1976) p. 220. [16] HEARLE, J. W. S.; SULTAN, M. A. I.: J. Text. Inst., 58, No.6, (1967) p. 251. [17] CLAYTON, F. H.: J. Text. Inst., No. 26, (1935) T171. [18] GARDMARK, L.; MARTENSOON, L.: Text. Res. J., 36, No. 12, (1966) p. 1037. [19] HEARLE, J. W. S.; SULTAN, M. A. I.; CHAUDHARY, T. N.: J. Text. Inst. 58, No. 1968, p. 103. [20] IGWE, G. J. I.; SMITH, P. A.: Melliand Textilber (Eng), 67, (1986) El04. [21] IGWE, G. J. I.: Needle felts in gas and dust filtration. Ellis Horwood Series in Chemical Engineering, (1987) p. 89. [22] HEARLE, J. W. S.; PURDY, A. T.: J. Text. Inst., 63, (1972) p. 475. [23] SUBRAMANIAM, V.; MADHUSOOTHANAN, M.; DEBNATH, C. R.: Effect of Web Weight, Needling Density and Depth of Needle Penetration on Fabric Mechanical Properties. International Conference on Nonwovens, (1992) p. 184.

R. P. Jamdagni; K. N. Chatterjee 26

KVALITATIVNÍ ASPEKTY VPICHOVANÝCH NETKANÝCH POLYESTEROVÝCH FILTRŮ PRO KONTROLU PRACHU

Náš výzkum byl zaměřen na vpichované netkané filtrační textilie vyrobené z polyesterových vláken pro filtraci prachu. Na laboratorně sestrojeném filtračním zařízení byly změřeny filtrační vlastnosti. Byl zkoumán vliv gsm tkaniny, hustota jehly a penetrace jehly na vlastnosti filtrace. Tkaniny s vyšším gsm vykazují vyšší filtrační účinnost filtru, ale za cenu zvýšené tlakové ztráty. Se zvyšující se hustotou jehly a hodnotou penetrace jehly se filtrační vlastnosti nejprve do určité míry zlepšily, avšak poté následoval pokles.

QUALITÄTSASPEKTE VON NICHT GEWOBENE NADELGELOCHTEN POLYESTERFILTERTEXTILIEN ZUR STAUBKONTROLLE Nadelgelochte nichtgewobene Filtertextilien, die aus Polyesterfasern gefertigt sind, wurden für die Eignung zur Staubfilterung getestet, wobei die Filtereigenschaften an einem speziellen Filtergerät gemessen wurden. Es wurden der Effekt von gms-Fasern, Nadeldichte und Nadeldurchdringung auf Filtercharakteristiken untersucht. Gewebe mit einem höheren gsm weisen eine höhere Filtrationseffizienz und Sammelkapazität aus, aber auf Kosten eines erhöhten Druckabfalls. Mit erhöhter Nadeldichte und erhöhtem Nadeldurchdringungswert verbesserten sich die Filtrationseigenschaften anfangs bis zu einem gewissen Ausmaß. Danach fand eine Reduktion statt.

JAKOŚCIOWE ASPEKTY IGŁOWANYCH NIETKANYCH FILTRÓW POLIESTROWYCH DO KONTROLI KURZU

Nasze badania dotyczyły igłowanych nietkanych tekstylii filtracyjnych wyprodukowanych z włókien poliestrowych i służących do filtrowania kurzu. Na skonstruowanym urządzeniu filtrującym dokonano pomiaru właściwości filtracyjnych. Badano wpływ ciężaru tkaniny (gsm), gęstość igły oraz penetrację igły na właściwości filtracyjne. Tkaniny o większej gramaturze (gsm) mają większy potencjał skuteczności filtracji i odseparowania, ale za cenę większej utraty naprężenia. Wraz z rosnącą gęstością igły i wartością penetracji igły właściwości filtracyjne najpierw do pewnego stopnia się poprawiły a następnie obniżyły.

27

ASSESSING GARMENTS FIT TO WOMAN’S BODY S. Jevšnik1; Z. Stjepanovič1; A. Rudolf1; D. Grujić2; T. Pilar3 University of Maribor, Faculty of Mechanical Engineering, Maribor, Slovenia; 2 University of Banja Luka, Faculty of Technology, Banja Luka, Bosnia in Hercegovina 3 Velesovo 27, 4207 Cerklje, Slovenia e-mail: [email protected] 1

Abstract Fit of a garment on a body model is an important factor for designing comfortable, functional and well fitted garments. The aim of the research was to research and estimate the fit of women’s garments to the body. Within this study, we designed and developed a number of styles of skirts and jackets. The conventional and virtual prototype development process was carried out first. Next, we defined the method for assessing the fit of real and virtual women’s garments to various body models. Finally, the assessment of how virtual and real garments fit to different body models was performed and a comparison between the conventional and virtual fit to the body was performed. Introduction Virtual prototyping is a technique in the process of garment development that involves application of computer aided design intended for garments development and virtual prototyping of them. It aimed to integrate all specific characteristics of the garment into the virtual prototype that fit the virtual human body model. Another characteristic of the virtual prototyping relates to its use in validation. Results of many recent studies show that virtual garment prototyping is a promising technique, which will due to its potential considerably replace conventional methods of clothing prototypes’ development. It is well-know that for virtual prototyping the virtual body model could be the parametric mannequin, measures of which could be adjusted according to measuring the real human body or body measures obtained on the basis of the human body scanning [3]. Additional research in this area obviously focuses on the development of efficient mechanical simulation models, which can accurately reproduce specific mechanical properties of textiles. The other aspect of this research focuses on modelling virtual humans to assure representation of the exact human body figure needed for virtual prototyping. Garment fit is regarded as the most important element to customers in clothing appearance. There are many definitions of the garment fit. One of them is “Clothing that fits well conforms to the human body and has adequate ease of movement, has no wrinkles and has been cut and manipulated in such a way that it appears to be part of the wearer” [1]. The fit of a garment depends on the selected construction system for pattern design [2, 3, 4]. Evaluation of the garment fit is usually performed using the fit evaluation scale. Since the virtual cloth simulation received much attention in the past decade, research in this area mainly focuses on comparison of the garment fit to the real, scanned and parametric mannequin of the used 3D CAD system, respectively [1, 3, 4, 5]. This study deals with the evaluation of women´s garments fit to different body models. For this purpose a comparison between the conventional and virtual fit to the body was performed.

28

1

Materials and methods

The study focuses on the research of women´s garments fit to the body. Real body model, parametric and scanned 3D body models were used for comparison of the real and virtual garments on the basis of the criteria for assessing the fit of clothing to different body models. The styles of women's jackets and skirts as well as basic properties of fabrics are represented in Tab. 1. All fabrics are suitable for upper garments. In addition, front parts of the jackets, collars and lapels were fused. Fusing was performed for all models using the same type of fusible interlinings. Fusible interlining had the following characteristics: basic textile material of 100 % polyester, thermoplastic adhesive of 100 % polyamide, thermoplastic adhesive quantity of 23 meshes and surface mass of fusible interlining of 35 gm-². Tab. 1: Styles of the women’s jackets and basic properties of the fabrics. Yarn density Fabric Surface Name and drawings of the Fabric composition mass Warp Weft jacket styles code [%] [yarns/cm] [yarns/cm] [g/m²] 85% linen N TK-1Z 15% polyamide 42 23.5 109 I 85% linen K TK-1Č 15% polyamide 42 23.5 113 A 98% cotton L TK-2M 2% elastane 85 34.0 200 I 98% cotton D TK-2Č 2% elastane 84 33.5 164 A M I A

TK-4B

N I K A S A N D Y V E R E N A

TK-1Č

TK-4M

TK-2Č TK-1Z

97% cotton 3% elastane 97% cotton 3% elastane 85% linen 15% polyamide 98% cotton 2% elastane 85% linen 15% polyamide

63

29.0

184

58

28.5

182

42

23.5

113

84

33.5

164

42

23.5

109

TK-3Z

100% linen

19.5

17.5

158

TK-4B

97% cotton 3% elastane

63

29

184

TK-3M

100% linen

20

18

170

Source: Own

The research was conducted in two stages: 1.

Selection of the women´s jackets and skirts styles, and fabrics and fusible interlinings for their production. The process of computer pattern design was carried out using the OptiTex CAD system.

29

2.

Evaluation of the jacket prototypes fit to the real, parametric and scanned body models depending on the mechanical properties of the used fabrics for this study

The evaluation procedure women garment fit is suitable for both real and virtual models and includes the following steps [5]: 

Selection of the jacket style.



Selection of the evaluation area on the jacket (Fig. 1).



Assessment of a jacket and skirt fit to the body model using the following criteria grades: 1 (good), 0 (satisfactory) and -1 (inappropriate), Tab. 2 and 3.

Source: [6]

Fig. 1: Three evaluation areas (coloured) of skirt and five evaluation areas of jacket (front and back views) Tab. 2: The evaluation areas and criteria for the jacket Area Evaluation Area definition Criteria description Grade area 15 cm above the Jacket fit to the body shape: Bust and bust line and up - Jacket fits the body shape 1 - Slight wrinkling of fabrics due to the body shape hips to 5 cm above - Strong longitudinal or transverse wrinkles 0 the jacket edge. -1 Jacket fit to the shoulders: Shoulder area - Just enough long shoulder and 10 cm 1 - Slight wrinkling in the shoulder area Shoulder below the 0 - Too long shoulders; strong wrinkling in the shoulder shoulder on the area -1 front part. The whole sleeve.

Sleeve fit to the body: - Great appearance of the sleeve - Slight wrinkling of the sleeve - Shift of the sleeve and wrinkling

Collar and lapels

The whole collar and lapels.

Collar and lapels fit to the body: - Smoothly lies on the front part - Slightly deviates from jacket - Turning up, tightening and wrinkling

Bottom edge

The whole bottom edge of jacket (5 cm).

Bottom edge fit to the body: - Clean straight line of the bottom edge - Slightly restless bottom edge - Bottom edge weaves

F R O

N T

Sleeve

30

1 0 -1 1 0 -1 1 0 -1

Area

Evaluation Area definition area 5 cm below the Back and shoulders and up hips to 5 cm above the bottom edge.

Criteria description Jacket fit to the body shape: - Jacket fits the body shape - Slight wrinkling of fabrics due to the body shape - Strong longitudinal or transverse

Grade 1 0 -1

Jacket fit to the shoulders:

Shoulders and 5 - Just enough long shoulder cm bellow the - Slight wrinkling in the shoulder area - Too long shoulders; strong wrinkling in the shoulder shoulder. The whole sleeve.

area Sleeve fit to the body: - Great appearance of the sleeve - Slight wrinkling of the sleeve - Shift of the sleeve and wrinkling

1 0 -1 1 0 -1

Collar

The whole collar.

Collar fit to the body: - Smoothly lies on the back part - Slightly deviates from jacket - Turning up, tightening and wrinkling

Bottom edge

The whole bottom edge of jacket (5 cm).

Bottom edge fit to the body: - Clean straight line of the bottom edge - Slightly restless bottom edge - Bottom edge weaves

The whole sleeve.

Sleeve fit to the body: - Great appearance of the sleeve - Slight wrinkling of the sleeve - Shift of the sleeve and wrinkling

The whole collar.

Collar fit to the body: - Smoothly lies on the back part - Slightly deviates from jacket - Turning up, tightening and wrinkling

Shoulder

B

A C K

Sleeve

Sleeve

Collar

Area from waist to the bottom edge

Bottom edge

The whole bottom edge of jacket (5 cm).

S

I

D E

Hips

Jacket fit to the body shape: - Jacket fits the body shape and side seam is in the middle - Slight wrinkling in hips area - Strong wrinkling in hips area, side seam is not in the middle Bottom edge fit to the body: - Clean straight line of the bottom edge on front and back part - Slightly restless bottom edge - Different length of jacket on the front and back part

1 0 -1 1 0 -1 1 0 -1 1 0 -1 1 0 -1

1 0 -1

Source: [6]

31

Tab. 3: The evaluation areas and criteria for the skirt Evaluation Area Area Criteria description area definition Waist area and Form of skirt waist on the body: 5 cm below the - The level of the waist on the line of the body - Slightly lowered belt is not in the line of the body Waist waist waist F R O N T

Hips and abdomen

Length

Waist

B A C K

Hips and abdomen

Length

Waist S I D E

Hips and abdomen

Length Source: [6]

32

Area 5 cm below the waist and 3 cm below the hips line. Whole length and 7 cm above the line of skirt edge Waist area and 5 cm below the waist

Area 5 cm below the waist and 3 cm below the hips line. Whole length and 7 cm above the line of skirt edge Waist area and 5 cm below the waist

Area 5 cm below the waist and 3 cm below the hips line. Whole length and 7 cm above the line of skirt edge

- Belt deviates significantly from the waist line on the body Longitudinal or transverse folds in fabrics: - No folds; garment fits the body line - Garment slightly deviates from the line of the body - Many transverse or longitudinal folds Draping of fabrics and line of skirt length: - Smooth wrinkles, straight line of skirt length - Less pronounced wrinkling, adjusted length - Uneven wrinkling, restless line of skirt length Form of skirt waist on the body: - The level of the waist on the line of the body - Slightly lowered belt is not in the line of the body waist - Belt deviates significantly from the waist line on the body Longitudinal or transverse folds in fabrics: - No folds garment fits the body line - Garment slightly deviates from the line of the body - Many transverse or longitudinal folds Draping of fabrics and line of length skirt: - Smooth wrinkles, straight line of length skirt - Less pronounced wrinkling, adjusted length - Uneven wrinkling, restless line of skirt length Form of skirt waist on the body: - The level of the waist on the line of the body - Slightly lowered belt is not in the line of the body waist - Belt deviates significantly from the waist line on the body Longitudinal or transverse folds in fabrics: - No folds garment fits the body line - Garment slightly deviates from the line of the body - Many transverse or longitudinal folds Draping of fabrics and line of length skirt: - Smooth wrinkles, straight line of length skirt - Less pronounced wrinkling, adjusted length - Uneven wrinkling, restless line of skirt length

Grade 1 0 -1

1 0 -1

1 0 -1 1 0 -1

1 0 -1

1 0 -1 1 0 -1

1 0 -1

1 0 -1

2

Results discussion

The main purpose of this study was to define and evaluate different women´s garment styles fit to the real and virtual body models. The research results of clothing fit on the real body and on the virtual body models (3D scanned and parametric models), are given in the form of: 

Graphical representation of jackets’ fit to all body models from front and back views, as well as side view and



Assessment of the jackets’ and skirts’ fit to the real and virtual body models.

The real and virtual prototypes of the jacket Lida made up of a fabric coded TK-2M and skirt made up of fabric coded TK-1Z are presented in Tab. 4 and 5. Furthermore, the estimation of fit for all analyzed women’s styles on real, parametric and scanned body is presented in Tab. 6 – 8. Tab. 4: Fit results for the jacket’s style Lida made up of fabric coded TK-2M Real prototype of Virtual prototype Virtual prototype on the jacket on the real on the scanned 3D the parametric 3D body model body model body model

View

FRONT

SIDE

BACK

Source: Own

33

Tab. 5: Fit results for the jacket’s style Sandy made up of fabric coded TK-1Z Real prototype of Virtual prototype Virtual prototype on the jacket on the real on the scanned 3D the parametric 3D body model body model body model

View

FRONT

SIDE

BACK

Source: Own

Tab. 6: Assessment of fit for individual areas of jacket prototypes on the real body model

SIDE

BACK

FRONT

Evaluation area Bust area Shoulder Sleeve Collar and lapel Bottom edge Back area Shoulder Sleeve Collar Bottom edge Sleeve and shoulder Collar Hips Bottom edge

Source: Own

34

Jacket NIKA-1Z Grade -1 0 1 3 5 3 1 5 5 4 4 1 1 7 2 2 5

9 7 11 2 7 10 4 10 5 8 8 4 5 8

4 4 2 13 4 1 8 2 10 7 1 10 9 3

Jacket NIKA-1Č Jacket LIDA-2M Jacket LIDA-2Č Jacket MIA-4B Grade Grade Grade Grade -1 0 1 -1 0 1 -1 0 1 -1 0 1 2 0 0 0 8 5 2 6 0 2 5 1 2 5

10 12 10 4 6 7 9 8 6 8 5 4 4 7

4 4 6 12 2 4 5 2 10 6 6 11 10 4

0 0 0 0 0 5 3 5 1 2 1 1 2 3

9 7 4 2 8 10 8 9 6 5 10 1 10 7

7 9 12 14 8 1 5 2 9 9 5 14 4 6

3 0 2 0 2 6 1 3 0 1 2 1 1 2

11 6 9 3 10 8 9 9 3 7 7 6 10 8

2 10 5 13 4 2 6 4 13 8 7 9 5 6

8 2 3 2 0 7 3 7 1 1 3 2 2 0

8 11 10 7 9 8 10 8 3 8 9 8 9 5

0 3 3 7 7 1 3 1 12 7 4 6 5 11

Jacket MIA-4M Grade -1 0 1 6 5 8 4 4 6 2 7 3 0 6 0 0 0

10 9 8 6 10 8 8 8 3 4 8 8 12 7

0 2 0 6 2 2 6 1 10 12 2 8 4 9

Tab. 7: Assessment of fit for individual areas of jacket prototypes on the scanned body

SIDE

BACK

FRONT

Evaluation area Bust area Shoulder Sleeve Collar and lapel Bottom edge Back area Shoulder Sleeve Collar Bottom edge Sleeve and shoulder Collar Hips Bottom edge

Jacket NIKA-1Z Grade -1 0 1 0 1 3 1 3 9 3 6 0 1 5 3 0 9

4 8 5 2 9 6 6 9 5 11 8 4 7 6

12 7 8 13 4 1 7 1 11 4 3 9 9 1

Jacket NIKA-1Č Grade

Jacket LIDA-2M Jacket LIDA-2Č Jacket MIA-4B Jacket MIA-4M Grade Grade Grade Grade

-1

0

1

-1

0

1

-1

0

1

-1

0

1

-1

0

1

0 1 1 2 3 3 1 3 0 7 5 0 1 8

7 4 10 2 2 12 8 8 2 6 7 7 5 6

9 11 5 12 11 1 7 5 14 3 4 9 10 2

1 1 1 1 5 6 2 5 0 2 5 3 3 10

9 4 8 2 8 8 8 7 4 11 8 2 9 5

6 11 7 13 3 2 6 4 12 3 3 11 4 1

2 3 4 0 6 4 2 4 1 3 2 1 4 11

6 3 5 2 10 10 5 7 2 9 8 5 9 4

8 10 7 14 0 2 9 5 13 4 6 10 3 1

0 1 2 1 0 3 2 2 9 1 2 7 1 5

7 3 4 5 7 10 8 10 2 7 7 5 7 6

9 12 10 10 9 3 6 4 5 8 7 4 8 5

1 2 2 1 0 3 3 1 5 0 0 6 0 4

4 3 4 4 5 10 7 8 8 6 9 5 10 8

11 11 10 11 11 3 6 7 3 10 7 5 6 4

Source: Own

Tab. 8: Assessment of fit for individual areas of jacket prototypes to the parametric body

SIDE

BACK

FRONT

Evaluation area

Jacket NIKA-1Z Grade -1 0 1

Jacket NIKA-1Č Grade -1 0 1

Jacket LIDA-2M Jacket LIDA-2Č Jacket MIA-4B Jacket MIA-4M Grade Grade Grade Grade -1 0 1 -1 0 1 -1 0 1 -1 0 1

Bust area

1

8

7

1

6

9

0

2

14

0

2

14

0

2

14

0

2

14

Shoulder

1

6

9

1

1

14

1

2

13

0

4

12

0

1

15

1

1

14

Sleeve

1

1

14

2

3

11

3

4

9

3

6

7

0

2

14

1

3

12

Collar and lapel

6

2

8

7

4

5

0

2

14

0

1

15

1

2

13

0

2

14

Bottom edge

3

8

5

4

7

5

4

7

5

2

9

5

0

2

14

0

3

13

Back area

0

7

9

0

5

11

0

5

11

1

5

10

1

8

7

0

9

7

Shoulder

1

1

14

1

1

14

1

1

14

1

0

15

1

3

12

1

0

15

Sleeve

1

6

9

1

6

9

3

2

11

3

3

10

1

5

10

0

4

12

Collar

1

0

15

1

1

14

0

0

16

0

1

15

2

5

9

0

0

16

Bottom edge

0

1

15

0

4

12

0

4

12

0

3

13

3

10

3

0

4

12

Sleeve and shoulder

0

0

16

1

6

9

1

4

11

0

2

14

0

3

13

1

3

12

Collar

6

3

7

6

3

7

0

6

10

0

2

14

1

2

13

2

4

10

Hips

1

7

8

1

10

5

0

7

9

0

8

8

1

9

6

0

10

6

Bottom edge

2

10

4

3

9

4

2

4

10

4

6

6

6

9

1

6

4

6

Source: Own

For assessing the women’s jackets and skirts have used parametric and scanned digital body models, as well as a real female body. The parametric model was selected from the base of different virtual parametric models of the human body, offered by the program OptiTex. [7]. Parametric models have defined the basic and the supplementary body measurements according to the of the real body measurement for body size 42. Virtual body scan was obtained with a 3D scanner Vitus Smart 3D at the Faculty of Textile Technology, University of Zagreb, Croatia. The scanned human body was suitable for further analysis after the reconstruction phase performed with the following computer programs: MeshLab, Blender and Atos. The final 3D body model was imported into the OptiTex PDS program for the simulation of virtual garments.

35

For virtual simulation of women garments the fabrics were defined with the following characteristics using the FAST measuring system in order to obtain the realistic virtual jacket prototypes measurements: tensile, bending, shear, surface thickness and fabric weight. 16 experts from the field of textile and clothing engineering were assessing and analyzing the fit of garments. Real prototypes of jackets got grades for all assessment criteria: good, satisfactory and inadequate fit, Tab. 4. In most cases the respondents assessed the collar and lapels of all jackets with grade ‘good’. The most frequent grade ‘satisfactory fit’ was given to jackets´ fit to the body figure on the front and back side as well as for sleeves. Grade ‘inadequate fit’ was given to prototypes Mia-4B and Mia- 4M for the bust area on the front part and on the back part and for the sleeve because of high stiffness and wrinkling of fabrics. The differences of grades are resulting from the fact that real prototypes are not made for particular women but the real prototypes were made for jacket size number 42. The results of the assessment of the fit of the jacket prototypes to the scanned 3D body model have shown very similar estimation for all analyzed jackets, Tab 5. Namely, the same fabric in two colours was used for one style. Therefore, it can be concluded that differences in the jackets’ fit to the scanned body model depend on the construction of the jacket and characteristics of the body model. The fit of all 3D jacket prototypes to the parametric body model was evaluated with grade ‘good fit’, Tab. 6. In most cases the respondents assessed the bottom edge in the front view with grade ‘satisfactory fit’. The bottom edge of the jacket styles Nika and Lida was slightly more turbulent due to the sewn pockets. In general, it was found that the respondents evaluated with grade ‘good fit’ all jacket styles on the parametric body model. The reason for this is the fact that a parametric body model is symmetrical and perfect. Therefore, the fit of jackets and apparel appearance were good. However, the simulation is not completely comparable with a real body model. Conclusion The estimation of garment fit to the body is very difficult because we cannot eliminate the subjective attitude of individual evaluators. Virtual prototyping has got a good potential; this confirms the needs of garment producers who want to have their products very soon on the market. In addition, the production processes usually take place in different parts of the world today. For these reasons suitable assessment protocols for garment fit have to be developed in the future for an appropriate dialogue between producers and costumers. Literature

36

[1]

YU, W.: Subjective assessment of clothing fit. Clothing appearance and fit: Science and Technology. Woodhead Publishing Limited, ISBN 1-85573-745-0, Cambridge, England, 2004

[2]

PILAR, T. at al: Evaluation of fitting virtual 3D skirt prototypes to body. Tekstilec, 2013, 56 (1) pp. 47-62.

[3]

JEVŠNIK, S. at al: Virtual prototyping of garments and their fit to the body. DAAAM International scientific book 2012. Vienna, 2012, pp. 601-618.

[4]

STJEPANOVIĆ, Z. at al: 3D virtual prototyping of clothing products. Innovations in clothing technology & measurement techniques. Lodz, 2012, pp. 28-41.

[5]

RUDOLF, A. at al: Influence of Knitted Fabric’s Stretch on Virtual Prototyping of the Underwear, Proceedings of 14th Romanian Textiles and Leather Conference, 46th International Federation of Knitting Technologists Congress, Sinaia, 2012, pp. 946-953.

[6]

PILAR, T.: Development of 3D Prototypes of Women’s Clothing. Master Thesis, University of Maribor, Maribor, 2012.

[7]

OptiTex. [online]. [accessed .

2012-09-29].

Available

from

WWW:

S. Jevšnik; Z. Stjepanovič; A. Rudolf; D. Grujić; T. Pilar 37

HODNOCENÍ DOBŘE PADNOUCÍCH ODĚVŮ NA ŽENSKÉ TĚLO Jak dobře padne oděv na modelu těla je důležitým faktorem pro vytváření pohodlných, funkčních a dobře padnoucích oděvů. Cílem výzkumu bylo prozkoumat a odhadnout, jak dobře padnou dámské oděvy na tělo. V rámci této studie jsme navrhli a vyvinuli celou řadu stylů sukní a sak. Nejprve byl proveden konvenční a virtuální proces vývoje prototypů. Následně jsme definovali metodu pro posuzování padnutí reálných a virtuálních ženských oděvů pro různé modely těla. Na závěr jsme vyhodnotili, jak virtuální a reálné oděvy padnou na různé modely těla a porovnali konvenční a virtuální padnutí na tělo.

BERECHNUNG DER ANPASSUNG VON KLEIDUNG AN FRAUENKÖRPER Die Anpassung eines Kleidungsstücks an das Körpermodell ist ein wichtiger Faktor fürs Design bequemer, funktioneller und gut angemessener Kleidung. Das Ziel dieser Arbeit besteht in der Untersuchung und Einschätzung der Anpassung von Frauenkleidung an den Körper. Innerhalb dieser Studie haben wir eine Anzahl von Stilen von Hemden und Jacken entworfen und entwickelt. Zuerst wurde ein konventioneller und virtueller Prototypentwicklungsprozess durchgeführt. Als Nächstes haben wir eine Methode für die Berechnung der Anpassung realer und virtueller Frauenkleidung an verschiedene Körpermodelle definiert. Am Schluss wurde eine Berechnung durchgeführt, wie virtuelle und reale Kleidung zu verschiedenen Körpermodellen passen, sowie ein Vergleich zwischen der konventionellen und virtuellen Anpassung an den Körper.

OCENA ODZIEŻY DOBRZE DOPASOWANEJ DO KOBIECEGO CIAŁA Dobre dopasowanie odzieży do ciała stanowi ważny czynnik w produkcji wygodnych, funkcjonalnych i dobrze leżących ubrań. Celem przeprowadzonych badań było stwierdzenie i ustalenie, na ile damskie ubrania dopasowane są do ciała. W ramach niniejszego opracowania zaproponowaliśmy i opracowaliśmy cały szereg fasonów spódnic i żakietów. W pierwszej kolejności był to konwencjonalny i wirtualny proces opracowania prototypów. Następnie zdefiniowaliśmy metodę oceny dopasowania realnych i wirtualnych ubrań damskich do różnych modeli ciała. Na zakończenie oceniliśmy, na ile ubrania wirtualne i realne dopasowane są do różnych modeli ciała oraz porównaliśmy konwencjonalne i wirtualne dopasowanie do ciała.

38

FABRICATION OF CROSS-LINKED GELATIN ELECTROSPUN NANOFIBERS CONTAINING ROSEMARY OIL FOR ANTIBACTERIAL APPLICATION Nazife Korkmaz1; Sena Demirbağ; M. Selda Tözüm; Sennur Alay Aksoy; Çağlar Sivri Süleyman Demirel University, Faculty of Engineering, Textile Engineering Department, Isparta, Turkey 1 e-mail: [email protected] Abstract In this study, fabrication of nanofibers with antibacterial property was aimed to obtain biopolymer-based nano-fiber product that is used for wound healing. For this aim, natural rosemary oil was used to give antibacterial activity to the nanofibers and gelatin polymer was used to produce nanofibers. According to literature survey, rosemary oil has antibacterial activity and it is also used in aromatherapy, topically to sooth muscles, and medicinally thanks to its antibacterial and antifungal properties. Gelatin is a natural biopolymer and extensively used in medical products such as wound dressings, drug delivery systems etc. Therefore, the combination of inherently beneficial effects of gelatin material with enhanced properties of nanofibers mats and rosemary oil was aimed at. In the study, gelatin nanofibers containing rosemary oil were fabricated by an electrospinning method. Gelatin was dissolved in distilled water/acetic acid at concentration of 10 % at first step. Then, rosemary oil and surfactant (Span 20) was added to solution and stirred for 6 hours. To get a cross-linked nano-fibrous mat, two different cross-linking methods and different cross-linkers were applied. In the first method, glutaraldehyde or tannic acid as a cross-linker was added to polymer solution before electrospinning. In the second method, nanofibers were spun from rosemary oil/gelatin solution and then cross-linked by GA and tannic acid, separately. Morphology and fiber diameter were investigated using SEM. FT-IR spectroscopy was used to identify cross-linked fiber structure and the presence of rosemary oil in electro spun mat. The solubility of cross-linked fiber mat was also investigated. Introduction Electrospinning is an inexpensive, effective and simple method to produce nanoscale fibers, which have intrinsically high surface to volume ratios, increased flexibility in surface functionalities, improved mechanical performances, and smaller pores than fibers produced using traditional methods [1]. Electrospun fibers have been used for advanced applications especially in biomedical field such as a smart wound dressing material and artificial scaffold for tissue engineering. According to literature, numerous synthetic biocompatible and biodegradable polymers such as poly(lactide), poly(glycolic acid), poly(caprolactone) and poly(ethylene glycol) and naturally derived biopolymers such as collagen, silk fibroin, alginate, gelatin, chitin and a blend of various biocompatible polymer pairs have been electro-spun into nanofibers for a multitude of biomedical applications such as scaffolds for use in tissue engineering, wound dressing, drug delivery and vascular grafts [2, 3]. Gelatin is a protein-based biopolymer derived from partial hydrolysis of native collagens, which are structural proteins found in parts of animal bodies, such as skin, tendon, cartilage and bone. Gelatin is extensively used in medical products such as wound dressings, drug delivery systems, sealants for vascular prostheses thanks to its high biocompatibility, biodegradability and bioactivity. In this study, gelatin nanofibers containing rosemary oil was fabricated for antibacterial applications. According to literature survey, rosemary oil has 39

antibacterial activity against Gram-positive and Gram-negative bacteria [4, 5]. Therefore it was added into nanofibers’ structure during electrospinning. Despite their potential, the electrospun fibers of gelatin are water soluble and mechanically weak. Thus, further treatments such as cross-linking to improve these properties are required. As seen from previous studies, electrospun gelatin fiber mats are successfully cross-linked by GA vapor by adding small amounts of GA to the gelatin solution before electrospinning process (one step cross-linking process) [6]. Another cross-linker used in study, tannic acid (TA), is a hydrolysable tannin as a natural phenolic cross-linker to modify gelatin and improve its mechanical performance [7]. This study focused on cross-linking of gelatin nanofibers containing rosemary oil. In the study, glutaraldehyde and tannic acid as crosslinkers were used. Cross-linking was carried out before and after the electrospinning process. 1

Materials and Methods

1.1

Materials

Gelatin (from porcine skin, type A) in powder form, acetic acid (99.8- 100, 5 %), tannic acid (C76H52O46) in powder form, glutaraldehyde (GA) solution (25 %) were purchased from Sigma-Aldrich. Hydrochloric acid (37 %) and toluene were obtained from the Ricdel-de Haör. Surfactant (Span 20) was a product of Merck. Sodium hydroxide (50 %) purchased from J.T. Baker. Natural rosemary oil was obtained from Botalife (Turkey). 1.2

Electrospinning Process

Gelatin of 10 wt % solution was prepared by dissolving gelatin in the mixture of distilled water and acetic acid. Then, 5 grams of rosemary oil and 1 gram of surfactant (Span 20) were added to the solution and stirred at room temperature for 6 hours. The distance between the grounded collector and needle tip was set to 12 cm. Electrospinning carried out at 17 kV, solution feed rate of 2 ml/h. 1.3

Cross-linking of Gelatin Nanofibers Containing Rosemary Oil

The cross-linking process of gelatin/rosemary oil electrospun mat was carried out by two different methods and cross-linkers. In the first method, 0.5 grams of glutaraldehyde or 0.09 grams of tannic acid were added to the polymer solution before electrospinning. Then, polymer solutions were electrospun. In the second method, nanofibers were spun from gelatin solutions containing rosemary oil and then cross-linked by GA or tannic acid. In the glutaraldehyde cross-linking process, a 0.5 grams of glutaraldehyde and 0.05 M, 37% hydrochloric acid that were used to adjust pH were mixed in 50 ml of toluene. Electrospun nanofiber mat was dipped in the prepared mixture for 24 hours at room temperature. Cross-linked nanofiber mat was washed to remove residual GA solutions. In the cross-linking process with tannic acid (TA), 0.09 grams of TA were dissolved in 100 ml distilled water and the pH of the solution was adjusted to 8 by adding NaOH solution. Electrospun nanofiber mat was dipped in this solution for 24 hours at room temperature. Cross-linked nanofiber mat was treated by series of washing process to remove residual TA. The information about nanofibers cross-linked is given in Table 1.

40

Tab. 1: Cross-linked nanofiber properties Nanofiber samples Cross-linker Sample 0 Sample 1 GA Sample 2 TA Sample 3 GA Sample 4 TA

Cross-linking step Before electrospinning Before electrospinning After electrospinning After electrospinning

Source: Own

1.4

Characterizations of Nanofibers

To investigate dissolvability of nanofibers, fabricated nanofiber mats containing rosemary oil were cut into pieces having the area of 3x3 cm2 and immersed in water at room temperature. In this test, to examine whether the sample was dissolved or not, the time required for dissolution was measured in case dissolution was performed. Photos of insoluble samples were taken at certain time intervals in 24 h. The morphology of the nanofibers was characterized by SEM images. FT-IR spectroscopy was used to identify cross-linked gelatin/rosemary oil nanofiber structure and the presence of rosemary oil in electrospun fiber mat. 2

Results and Discussion

2.1

Results of Dissolvability Test

The dissolvability test was applied to investigate whether nanofibers were cross-linked or not. Gelatin polymer is soluble in water at room temperature. Once cross-linking of gelatin was achieved, its solubility could be prevented. Therefore, nanofibers treated with cross-linkers by different methods were tested for dissolvability. Figure 1 shows dissolvability test results of uncross-linked nanofibers. Uncross-linked electrospun gelatin fiber mat containing rosemary oil began to form gel and shrink as it contacted with water and then almost dissolved.

Source: Own

Fig. 1: Dissolvability test of uncross-linked gelatin nanofiber (Sample 0)

41

Dissolubility test results of Samples 1 that were cross-linked with GA before electrospinning, were given in Figure 2. According to the photos, nanofibers did not dissolve during 24 h in the water.

Source: Own

Fig. 2: Dissolvability test result of Sample 1 According to literature, TA cross-links the gelatin polymer at pH 8. Cross linkage between reactive groups of gelatin and tannic acid occurs at this pH [7]. In the study, electrospinning of this solution could not be carried out due to salt crystals formation between the acid and basic (NaOH used for pH adjusting) groups in solution when the pH of the polymer solution was adjusted to pH 8. For this reason, nanofibers were spun from the gelatin polymer solution containing TA at pH 5. Figure 3 shows dissolubility test results of this sample (Sample 2). As seen from Figure 3, nanofiber sample was entirely dissolved in water.

Source: Own

Fig. 3: Dissolvability test result of Sample 2 Cross-linked gelatin nanofiber mat containing rosemary oil by glutaraldehyde after electrospinninig process showed no gelation, shrinkage and deformation as cross-linked gelatin nanofiber immersed in water. There was no gelation, shrinkage and deformation even 42

after six and twenty four hours following the moment surface of electrospun gelatin fiber mat immersed in water (Figure 4). The water resistant ability of the surface was a proof of crosslinking gelatin nanofiber mat containing rosemary oil by glutaraldehyde.

Source: Own

Fig. 4: Dissolvability test of Sample 3 Figure 5 shows the dissolubility test photos of Sample 4. There was no gelation, shrinkage and deformation of electrospun gelatin fiber mat immersed in water even after six and twenty four hours. The water resistant ability of surface was a proof of cross-linking gelatin nanofiber mat containing rosemary oil by tannic acid.

Source: Own

Fig. 5: Dissolvability test result of Sample 4 2.2

Results of SEM Analysis

The SEM image of gelatin/rosemary oil nanofibers were given in Figure 6. It clearly shows the fibers with nano-size have almost uniform diameters. There are no beads and continuous fiber structure was achieved.

43

Source: Own

Fig. 6: SEM images of Sample 0 (a) X20000 (b) X10000 To investigate the effect of the cross-linking process on the morphology of nanofibers, SEM images of gelatin/rosemary oil nanofibers cross-linked with GA before electrospinnig process were given in Figure 7. According to the SEM images, nanofibers which belong to Sample 1 have nano-sized and uniform diameter distribution. There is no negative effect of GA addition on the morphology of electro spun nanofibers.

Source: Own

Fig. 7: SEM images of Sample 1 (a) X20000 (b) X10000 SEM images of nanofibers cross-linked by GA after electrospinning given in Figure 8 clearly show the change in morphology. Net-like structure formed due to cross-linkage occurrence between fibers by GA cross-linking. It was concluded that net-like structure caused the morphological change.

Source: Own

Fig. 8: SEM images of Sample 3 44

SEM images of Sample 4 given in Figure 9 show deformation of the structure and loses fibrous structure. Furthermore, formation of crystal particles on the surface nanofibers was observed. These nanofibers were crosslinked by TA in the water at pH 8. It was thought that crystal particles formed on the surface nanofibers due to chemical interaction between TA that shows weak acidity and sodium hyroxide used for adjusting pH.

Source: Own

Fig. 9: SEM images of Sample 4 2.3

Results of FT-IR

According to the results of the dissolubility test and SEM analysis, gelatin/rosemary oil nanofibers encoded as Sample 1 can be chosen as ideal cross-linked nanofibers. Therefore FT-IR analysis was performed on these nanofibers to investigate the presence of rosemary oil in structure and identify cross-linked structure. Figure 10 shows the FT-IR spectrums of nanofibers, gelatin, rosemary oil and glutaraldehyde. According to FT-IR spectra of gelatin, there is a wide peak at 3462 cm-1 and this peak is N-H stretching peak in gelatin structure. These peaks arise at 3300 cm-1 and 3426 cm-1 in IR spectrum of cross-linked gelatin nanofibers (Figure 10 c). According to FT-IR spectra of rosemary oil (Fig.10), there are sharp peaks at 2923 cm-1 and 2854 cm-1 that are C-H stretching peaks of rosemary oil [8]. The peaks at 2928 cm-1 wave length in FT-IR spectrum of nanofibers are characteristic peaks of rosemary oil and prove presence of rosemary oil in the structure of nanofibers. During the cross-linking process by glutaraldehyde, aldimine linkage (CH=N) occurs due to chemical reaction between amino groups of gelatin and aldehyde groups of glutaraldehyde. The characteristic absorption of the aldimine groups arises at 1450 cm-1 [2]. This peak was observed in FT-IR spectrum of cross-linked gelatin nanofibers containing rosemary oil (Figure 10 c). This finding is a proof of cross-linking of gelatin with GA.

45

Source: Own

Fig. 10: FT-IR spectra of gelatin (a), glutaraldehyde (b), cross-linked gelatin nanofibers containing rosemary oil by adding glutaraldehyde to the gelatin/rosemary solution before electrospinning process (c) Conclusion In this study, fabrication of cross-linked gelatin nanofiber containing rosemary oil was carried out. Rosemary oil was dispersed in gelatin solution and the solution was electrospun to produce gelatin nanofibers containing rosemary oil. In the study GA and TA were used as cross-linkers. Cross-linking was carried out by two different methods. One of the methods focused on adding cross-linkers to polymer solution before electrospinning. In another method, cross-linking was carried out after electrospinning process. Nanofibers were tested and characterized by a dissolubility test, SEM and FT-IR spectroscopy analysis. According to the test and the analysis results, cross-linking with TA couldn’t be achieved before electrospinning as the morphology was affected negatively by TA cross-linking after electrospinning. GA cross-linking before electrospinning gave the most suitable results related to dissolubility and morphology. The rosemary oil content and cross-linkage with GA of these nanofibers were also proved by FT-IR analysis. Literature

46

[1]

SCHIFFMAN, J. D.; SCHAUER, C. L.: Bio- macromolecules, 8, 2665-2667.

[2]

NGUYEN, T.; LEE, B.: J. Biomedical Science and Engineering, 3, 1117-1124.

[3]

RATANAVARAPORN, J.; RANGKUPAN, R.; JEERATAWATCHAI, H.; KANOKPANONT, S.; DAMRONGSAKKUL, S.: International Journal of Biological Macromolecules, 47 (2010) 431–438.

[4]

MOGHTADER, M.; AFZALI, D.: American-Eurasian Journal of Agricultural & Environmental Sciences, 5 (3): 393-397.

[5]

FU, Y.; ZU, Y.; CHEN, L.; EFFERTH T.; LIANGH, H.; LIU, Z.; LIU, W.: Planta Medica, 7 (12).

[6]

ZHANG, Y. Z.; VENUGOPAL, J.; HUANG, Z.-M.; LIM, C. T.; RAMAKRISHNA, S.: Polymer, 47 (2006) 2911–2917.

[7]

ZHANG, X.; DO, M. I.; CASEY, P.; SULISTIO, A.; QIAO, G. G.; LUNDIN, L.; LILLFORD, P.; KOSARAJU, S.: J. Agric. Food Chem., 58(2010), 6809-6815.

[8]

KAYAHAN, E.; AKSOY, K.; ÖNEM, E.: The Production of Antibacterial Microcapsule Containing Rosemary Oil Using Complex Coacervation Method. 14th National & 1st International Recent Developments, Textile Technology and Chemistry Symposium, Bursa, 2013, 131-133.

Nazife Korkmaz; Sena Demirbağ; M. Selda Tözüm; Sennur Alay Aksoy; Çağlar Sivri 47

VÝROBA ŽELATINOVÝCH NANOVLÁKEN OBSAHUJÍCÍCH ROZMARÝNOVÝ OLEJ S ANTIBAKTERIÁLNÍMI ÚČINKY

Tato studie se zabývá výrobou nanovláken s antibakteriálními vlastnostmi zaměřenou na získání nanovlákenného produktu na bázi biopolymeru, který se používá pro hojení ran. Za tímto účelem byl použit přírodní rozmarýnový olej, který posiluje antibakteriální aktivitu nanovláken. K výrobě nanovláken byl použit želatinový polymer. Jak potvrzuje studium literatury, rozmarýnový olej má antibakteriální účinky, a je také používán v aromaterapii, lokálně k uklidnění svalů, a díky svým antibakteriálním a antimykotickým vlastnostem má i léčivé účinky. Želatina je přírodní biopolymer a její využití v medicíně je široké – například se používá při ošetřování ran nebo je součástí různých léčiv atd. Proto jsme se zaměřili na kombinaci nepopiratelně blahodárných účinků želatiny s vysoce užitnými vlastnostmi nanovlákenných látek a rozmarýnu.

HERSTELLUNG VERNETZTER ELEKTRONISCH GESPONNENER NANOFASERN AUS GELATINE, DIE ROSMARINÖL FÜR ANTIBAKTERIELLE ANWENDUNG ENTHALTEN In dieser Studie ging es darum, Nanofasern mit antibakteriellen Eigenschaften zu produzieren. Das Ziel bestand in der Gewinnung von Nanofaserprodukte auf Biopolymerbasis, das zur Wundbehandlung Verwendung findet. Zu diesem Zweck wurde natürliches Rosmarinöl benutzt, um die antibakterielle Aktivität der Nanofasern zu verstärken. Zur Produktion von Nanofasern wurde Gelatinpolymer verwendet. Laut Literatur wirkt Rosmarinöl antibakteriell und wird ebenfalls in der Aromatherapie angewendet, namentlich um die Muskeln zu beruhigen. Außerdem die antibakteriellen und antifungiellen Eigenschaften des Textils heilsame Wirkung. Gelatine ist ein natürliches Polymer und wird hauptsächlich bei der Wundbehandlung usw. verwendet. Daher richtete sich unser Interesse auf die Kombination der inhärent heilsamen Effekte von Gelatinematerial mit den verbesserten Eigenschaften von Nanofasermatten und Rosmarinöl.

PRODUKCJA ŻELATYNOWYCH NANOWŁÓKIEN ZAWIERAJĄCYCH OLEJ ROZMARYNOWY O DZIAŁANIU ANTYBAKTERYJNYM

Niniejsze opracowanie poświęcone jest produkcji nanowłókien o działaniu antybakteryjnym, dotyczącej pozyskiwania produktu z nanowłókien na bazie biopolimeru, który stosowany jest do gojenia ran. W tym celu zastosowano naturalny olej rozmarynowy, który wzmacnia antybakteryjne działanie nanowłókien. Do produkcji nanowłókien użyto polimeru żelatynowego. Jak wynika z literatury, olej rozmarynowy ma działanie antybakteryjne i stosowany jest również w aromaterapii, miejscowo do uspokojenia mięśni i dzięki swoim cechom antybakteryjnym i antygrzybiczym ma także działanie lecznicze. Żelatyna to naturalny biopolimer, który jest szeroko stosowany w medycynie – przykładowo używany jest do opatrunku ran lub jako element różnych substancji leczniczych itd. Dlatego skupiliśmy się na połączeniu niepodważalnego korzystnego działania żelatyny i wysoce skutecznych właściwości substancji nanowłóknowych i rozmarynu.

48

IMPACT OF MATERIAL PARAMETERS ON TEMPERATURE FIELD WITHIN CLOTHING LAMINATES Ryszard Korycki1; Halina Szafranska2 Lodz University of Technology, Faculty of Material Technologies and Textile Design, Department of Technical Mechanics and Computer Science, Lodz, Poland; 2 University of Technology and Humanities, Faculty of Material Science, Technology and Design, Department of Shoes and Clothing Technology, Radom, Poland e-mail: [email protected] 1

Abstract Inlayers secure both aesthetic qualities and stiffness against creasing of clothing laminates. Laminate is created by thermoplastic glue between inlayer and clothing material which is softened by heat. State variable is temperature. Temperature distributions within laminate can be determined by numerical simulation for different temperatures of heating plates. Impact of different material parameters on temperature distribution is analysed. Introduction Inlayers secure aesthetic qualities and material stiffness against creasing of clothing laminates [1, 2, 3, 4]. Some paremters of inlayers are discussed by different authors [3, 4]. The substantial problem is a choice of technology, i.e. heating system applied to soften the polymer during lamination cf. Sroka, Koenen [5]. There are some important technological parameters of clothing laminates: temperature, heating time, pressure applied after heating, external material characteristics, kind of polymer glue, characteristics of a heater system. Let us first determine the physical model. State variable is the temperature within laminate structure which consists of inlayer, external material and polymer glue points. It should effectively describe the technological process. The structural shape is defined by vector of crucial point coordinates. The most important information is the temperature distribution within laminate during the heating phase. The only heat source are heaters in a heating device. Heat is transported through inlayer, polymer glue layer and textile material. There are different heat loss mechanisms by radiation, convection and conduction on appropriate material surfaces. The next step is to describe the mathematical model. Heat transfer is described by heat transport equation and set of boundary and initial conditions, cf. Li [6]; Dems, Korycki [7]. Heat transfer equation is the second-order differential correlation with respect to vector of coordinates. The problem can be solved by using different methods. The most popular is the numerical integration within structure [8, 9]. The other method is to introduce first variational form and find its solution. The main goal is to analyze the sensitivity of temperature field of polymer glue layer with respect to different material and technological parameters. Various descriptions of polymer glue distribution can be introduced. It can be modeled as a separate layer or by means of regular or irregular distributed points. Additionally, different heat-insulating protections can be introduced to improve heat transfer, cf. side housings. Generally speaking, the analyzed problem has a 3D space character. To simplify the solution, some cases can be reduced to an optional cross-section of structure. Therefore, space 3D problem can be reduced to its plane 2D cross-section. The important factor describing the structure can be the mean temperature in the glue layer which is assumed as a comparative element to estimate the sensitivity. 49

1

Description of heat transport

Clothing materials and inlayer made of textiles have periodically repeteable structure which should be first homogenized. There are a few effective homogenization methods [7, 10]. The most applied is the rule of mixture defined in the following form. λz  λm ξ m  λf ξf ;

ξm 

Vm Vf ; ξf  . Vm  Vf Vm  Vf

(1)

where Vm is volume of fibres in m3, Vf is volume of interfiber spaces filled by air or the glue in m3, λm; λf describe heat conductivity coefficients of material (m) and filling (f) in W/(m K), ξm; ξf are volume coefficients of fibres of volume Vm and the interfiber spaces of volume Vf. Heat is transported through polymer points as well as air between the glue. Both polymer glue and air are homogeneous. The polymer glue layer should secure the correct connection between the inlayer and textile material. The most effective method is to apply the point-wise spread procedure of polymer. We obtain regular and irregular polymer point distribution for different scales described as “mesh” parameter or “computer point” parameter. Consequently, the most simple and effective method is to define polymer glue as the continuous layer.

Source: Meyer

Fig. 1: Scheme of the continuous automatic fusion press KFH 600 for shirt – and blouse fusion with pressure cooling station at the output

Source: Meyer

Fig. 2: Scheme of the Interval Contact Cooling with the CoolVac System 50

The desription of heat transport depends on technology and heating press applied. There are different solutions of various heating systems. Let us assume the continuous automatic fusion press KFH 600 for shirt – and blouse fusion with pressure cooling station at the output, cf. Sroka and Koenen [5], Figure 1, Figure 2. Press device has the additional contact cooling to secure the regular heat transport and equalized temperature within glue layer. Let us assume the steady heat transport described by time-independent heat flux density of heating devices. Neither inlayer nor textile structures contain heat sources. The only heat source are always heaters within heating press. It means that heat can be only lost during heating process by laminate. Heat can be accumulated by textile fibers and transported to surroundings through external structural boundary. Introducing now heat balance which is the sum of heat losses, we formulate the heat transport equation. It is the second-order differential equation with respect to vector of coordinates. To solve the above equation, it is necessary to determine the set of boundary conditions. It depends on the particular solution of heating press, cf. Figure 3. 1

2

6

5

3

4

7

1 – heating elements, 2, 7 – heating devices, 3 – inlayer, 4 – homogenized polymer layer, 5 – side thermal housing, 6 – outer textile material Source: Own

Fig. 3: Scheme of material layers in heating device The upper part of inlayer and the lower part of textile material are exposed to constant temperature T = T0. This boundary portion ΓT is subjected to the first-kind condition. The side parts of heated elements as well as external housing are subjected to convective and radiative heat transport. There are boundary parts ΓC and Γr loaded by convectional and radiational heat flux densities i.e. the third-kind and radiation conditions. We assume on internal boundaries Γi the same heat flux densities, i.e. the fourth-kind conditions. Heat transport equation for (i)-th layer supplemented by set of conditions is shown in Figure 4 and described by Eq. (2). ΓC: qn=qn conv r

Γr: qn=qn

Γi (i) (i+1) qn =qn ΓT T=T Γi

ΓC: qn=qn conv r

Γr: qn=qn

0

0

ΓT T=T Source: Own

Fig. 4: Boundary conditions of system inlayer – polymer glue – textile material

51

T i  x   T 0 x  x  T ;

i   x  q i  x   hTx  - T x  x  C ; divq  0 x  ; x   ; nC  i    i i  i  *  y  q n r i  x   σTx 4 x  r ; q  A  T  q

qn

i 

(2)

x   q n i1 x  x  i .

where q is vector of heat flux density, q* is vector of initial heat flux density, qn=n·q denotes vector of heat flux density normal to surface defined by unit vector n, A is matrix of heat conduction coefficients, T is temperature, t is real time, T0 denotes prescribed temperature, h is surface film conductance, T is surrounding temperature, σ is Stefan-Boltzmann constant. 2

Impact of material parameters on temperature field

There are some basic parameters which can influence the clothing laminate. The most important are the following: 

Type of laminate. Inlayer can be made of different textiles: fabrics, knitted fabrics and non-wovens which depends on predicted applications. Thus, surface mass and internal porosity are also important and limited for the specific laminate.



Type of fibers within inlayer; the most popular are: polyester, polyamide, cotton, viscose, Lycra-fibers and bamboo fibers.



Place and area of application which determines stiff or the more flexible connection.



Finishing procedure which secures stability and aesthetic qualities of textile laminate.



Lamination technology defined by heat source parameters, location of heating devices, time of heating and time of pressure, force within the pressure roller etc.

Let us analyze the sensitivity i.e. the impact of the above mentioned parameters on temperature distribution within polymer glue layer. To determine temperature fields in textile laminate, it is convenient to assume the same heat flux density of the heater. The homogenized polymer layer has the same geometry and heat transport conditions within the heating device. The heat description is consequently simplified to the 2D plane problem. 2.1

Impact of material porosity on temperature field

We assume the outer textile made of woven fabric and the cotton inlayer, both of isotropic heat transfer properties. Material parameters can be defined according to [6,11,12]. Isotropic material has the single-component matrix of heat transfer coefficients defined for i-th layer A i   λ i   λ ; i=1,2,3; (for inlayer, polymer layer, outer textile material). Heat transfer coefficient of cotton fibre before homogenization is constant λ=0,072W/(mK) whereas of polymer glue temperature-dependent: λ=0,08W/(mK) for T