Scholarly article on topic 'Wool and cotton blends for the high-end apparel sector'

Wool and cotton blends for the high-end apparel sector Academic research paper on "Agriculture, forestry, and fisheries"

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Abstract of research paper on Agriculture, forestry, and fisheries, author of scientific article — Raechel Laing, Sophie Wilson

Abstract Branded blends of wool and cotton for high-end apparel fabrics were established in Britain and later exported to many English-speaking countries during the 19th century (e.g. woven fabrics Viyella™, 55% wool, 45% cotton; Clydella™, 81% cotton, 19% wool). During the late 20th century, cotton and wool blend yarns for high-end apparel applications were developed in Australia (Colana®, 70% cotton, 30% wool). None of these branded blends of wool and cotton has a current market presence, yet there is evidence of relevance and interest in such blends for the high-end apparel market. How can we account for this disappearance and for the renewed interest?

Academic research paper on topic "Wool and cotton blends for the high-end apparel sector"

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Procedía Engineering 200 (2017) 96-103

www.elsevier.com/locate/procedia

3rd International Conference on Natural Fibers: Advanced Materials for a Greener World, ICNF

2017, 21-23 June 2017, Braga, Portugal

Wool and cotton blends for the high-end apparel sector

Raechel Lainga, Sophie Wilsonb

aCentre for Materials Science and Technology, University of Otago, Dunedin, New Zealand bCentre for Materials Science and Technology, University of Otago, Dunedin, New Zealand

Abstract

Branded blends of wool and cotton for high-end apparel fabrics were established in Britain and later exported to many English-speaking countries during the 19th century (e.g. woven fabrics Viyella™, 55% wool, 45% cotton; Clydella™, 81% cotton, 19% wool). During the late 20th century, cotton and wool blend yarns for high-end apparel applications were developed in Australia (Colana®, 70% cotton, 30% wool). None of these branded blends of wool and cotton has a current market presence, yet there is evidence of relevance and interest in such blends for the high-end apparel market. How can we account for this disappearance and for the renewed interest?

© 2017 The Authors. Published by Elsevier Ltd.

Peer-review under responsibility of the scientific committee of the 3rd International Conference on Natural Fibers: Advanced Materials for a Greener World.

Keywords: cotton, wool, natural fibre blends, apparel, next-to-skin

1. Introduction

Protein fibres for high-end applications include wool, particularly in human health and well-being [1], cashmere, and silk. However, world demand over the period 1982-2015 for wool fibre decreased (1.62 to 1.16 million tons respectively), for silk fibres increased slightly (0.06 to 0.18 million tons respectively), while demand for all fibres increased (13.10 to 64.63 million tons respectively) [2]. (Data on cashmere is not included in these world summaries.)

* Corresponding author.

E-mail address: raechellamg@otago.ac.nz

1877-7058 © 2017 The Authors. Published by Elsevier Ltd.

Peer-review under responsibility of the scientific committee of the 3rd International Conference on Natural Fibers: Advanced

Materials for a Greener World

10.1016/j.proeng.2017.07.015

Demand for synthetic fibres accounts for most of the total fibre increase [2], but cotton, also widely used increased during the same period (14.71 to 23.60 million tons respectively). What is unclear in these data is the percentage/volume end use of the different fibre types: what volumes are used in industrial, medical, agricultural, geotextiles, technical, apparel? We do know there is continuing interest in natural fibres such as wool and cotton for the high-end apparel market. One question then is what benefits accrue for the high-end next-to-skin product market by blending wool with cotton? The present paper seeks to account for the re-emergent interest in those blends, and known or perceived advantages. The three key issues are: 1 human physiological benefits, 2 environmental implications, 3 culture-bound preferences for fibre types.

2. Key issues

2.1. Human physiological benefits

2.1.1. Overview

Evidence of effects of apparel systems on human performance and physiology has strengthened since the 1980s, in workplaces, in sport, and in health [3, 4]. Properties of fabrics from which these systems are made, at least for highend next-to-skin products, are those related to heat and vapour transfer; moisture absorption and perception of dampness; tactile properties; development, retention and release of human body odour. Blends of wool and cotton exhibiting many desirable attributes were available during the early 20th century (e.g. Viyella™, Clydella™) and again at the end of the 20th century (e.g. Colana®). These properties were neither well-understood at that time, nor did effects of the fabrics in garment form on human responses attract much attention, notwithstanding high visibility in national sporting applications (e.g. in Olympic Games [5] and in international cricket [6]. Some general disadvantages were apparent; wool fabrics with rather poor resistance to abrasion, cotton fabrics with rather poor resistance to creasing.

2.1.2. Heat and vapour transfer

Heat and vapour transfer are important properties for next-to-skin textiles as they have a major effect on wearer perceptions of acceptability. Common physiological indicators include heart rate, core temperature, skin temperature at various body sites, sweat output/rate, change in body mass, and humidity at the skin surface: specific and general perceptions are useful additional indicators. Few human trials investigating blends of wool and cotton have been identified, although trials comparing effects of both wool and cotton (and other) fibres have been published.

The perception of temperature change resulting from the heat of sorption with wool fabrics has been examined through wear trials. Stuart et al [7] compared mittens of 100% acrylic (low heat of sorption) and 100% wool (high heat of sorption), and concluded the temperature change caused by heat of sorption was perceptible: dry 100% wool mittens were warmer than both 100% acrylic and 100% wool mittens that had been conditioned to 80% relative humidity. In another study, effects on thermal performance during wind assault showed cotton/wool blends were superior to matched fabrics of 100% cotton and of 100% polyester, although no perceptual differences were observed [8]. The authors speculated that evaporative heat loss from the cotton/wool blend was greatest because of reduced thermal insulation after moisture from the microclimate had been absorbed, given the hygroscopicity of both cotton and wool. Vokac et al [9] compared vests of double cotton, polypropylene and cotton, and polypropylene as part of a layered assembly. A lower skin temperature was observed with the double cotton compared to double polypropylene: as structures were not matched, results are likely to be confounded. Participants could not detect differences between the cotton and polypropylene items notwithstanding the lower skin temperature under cotton. Next-to-skin garments constructed from 100% cotton have been reported to retain lower garment microclimate temperatures than those made from polyester [10]. Polyester worn over the skin has been shown to result in skin with higher relative humidity than fabrics made from cotton and linen. Five fabrics manufactured as protective overalls (67% polyester, 33% cotton; 100% oven dried wool; 100% aramid; 100% wool; 100% cotton) were evaluated to establish whether or not physiological effects could be identified [11, 12]. Differences in temperature and in humidity (instrumental, sensory) were non-significant. Similarly, in a study on temperature change inside sock/shoe assemblies no significant changes in temperature with any sock were detected (100%

cotton; 53% polyester, 37% cotton, 8% olefin, 1% natural latex, 1% spandex; 98% polyester, 2% spandex [13]). In this study, participants did recognise a slightly lower temperature with the polyester and polyester blends, with cotton seemingly retaining a slightly higher temperature.

The perception of coolness of a range of fabrics (different structures and fibre types) has been reported to not be correlated with a drop in skin [14]. Similarly, no perceptive differences were detected between cotton or synthetic-fibre socks during a 30-minute run [15], although the actual skin temperature under the synthetic sock was lower. No significant differences between socks of 100% cotton and 100% acrylic worn during long-distance running were observed for dampness; temperature; friction; and blister incidence, severity and size [16]. Based on their earlier investigation, the authors speculated a dense structure would provide superior properties in relation to water transfer.

Investigations on fabrics rather than garment assemblies have been widely published, blends of wool with other than cotton compared to 100% wool [17]. Basic performance properties (e.g. resistance to pilling and to abrasion, grab and tear strength) of woven fabrics made from combed cotton and scoured wool (short fibre) have been reported [18]. Varieties of cotton (31 different sources) manufactured into matched single jersey influence moisture vapour transport through those fabrics [19]. Different yarn counts and twist values of matched cotton single jersey have also been identified as affecting moisture transport, the higher twist coefficients creating compact structures with lower absorption rates, and finer yarns linked to faster absorption and shorter wetting time [20]. Knit fabrics manufactured from cotton blended with different proportions of angora (95% cotton, 5% angora; 85% cotton, 15% angora; 75% cotton, 25% angora) have been reported as having enhanced thermal properties [21].

2.1.3. Moisture absorption and perception of dampness

Perception of wettedness/moisture is influenced by temperature and tactile receptors which are affected by the rate and direction of temperature change [22, 23]. Wettedness is highly relevant in next-to-skin garments, as when the perception of this is strong, discomfort and dissatisfaction will be evident. Perceptions of dampness generally increase with increasing levels of moisture: in the case of wool gradually; in the case of polyester rapidly at low levels of moisture then little change; in the cases of cotton and a wool/polyester blend, the responses were similar to wool to begin (low moisture) and then polyester (higher moisture) [24]. Kaplan et al noted a difference in sensation of dampness between non-hygroscopic fabrics including polyester and polyamide compared to cotton and cotton blends, the latter being sensed as less damp under conditions in which sweating was simulated [14].

Both wool and cotton fibres are known to absorb moisture, but unlike cotton, wool releases heat, measurable in fabrics and garments (wool fabrics can absorb a large volume of water without feeling wet/damp). Heat of sorption provides an advantage to wearers in that it buffers the negative effect experienced when moving from a warm to a cool/cold environment [7]. Buffering effects have been observed by Laing et al during human trials with wool next-to-skin [25]. The properties of a cotton/wool blend might be expected to be superior to a matched fabric of 100% cotton in a next-to-skin application given heat of sorption. A dominant variable in moisture absorbed by a fabric is its thickness/structure [26], so with more fibre present, in the case of wool, greater heat of sorption is likely.

2.1.4. Tactile properties

Fabric-skin interactions have been investigated through wear trials with wool, cotton, and synthetic fabrics, but little is evident on blends. Tactile properties of cotton and wool fabrics (prickliness, thermal/moisture) of 33 woven shirt fabrics (plain, twill, doeskin, gabardine, crepe, jacquard) were determined by Wang et al through wear trials (Wang, Zhang et al. 2003). Fibre content differed (100% wool; 45% wool, 55% polyester; 100% cotton; 100% silk). Silk was rated most strongly for 'comfort', with the wool/ polyester blend rated the lowest. Wang et al reported the light-weight wool less 'comfortable' than the other fabrics [27]. The prickle sensation evident with some wool is one possible explanation. As the temperature increased from 240C to 290C, the prickle sensation of the wool fabrics became more pronounced. A similar pattern was evident with the onset of sweating. Because cotton fabrics/clothing are generally perceived as comfortable, a blend with wool may result in poorer tactile properties, but improved acceptability in that the skin will be drier.

Qualities of skin affect skin-fabric interaction. Perception of fabrics in contact with hairy skin compared to glabrous skin may differ, and the presence of moisture on the skin also affects perceptions (e.g. unmatched woven fabrics 100% coarse wool, 100% cashmere, 100% wool) [28]. Wool, cotton and polyester reportedly behave similarly when on wet skin, suggesting the presence of water may be more important than fibre type. Similarly, next-to-skin natural and synthetic fabrics have been compared to determine transepidermal water loss from the stratum corneum (16 fabric types: 100% wool, 100% cotton, 100% acrylic, 100% nylon, a blend of 65% cotton, 35% polyester; different structures) [29]. No significant changes in transepidermal water loss for any fabric type when dry were observed, however, when wet, wool and cotton fabrics increased stratum corneum hydration compared to both the control and to the fabrics in a dry state.

Forearm tests have been used in investigations of fabric tactile properties, but are less sensitive at least to prickle than wear trials [27]. However, the forearm test has been reported as useful to detect the level prickle in wool fabrics. Expert testers in an investigation by Naylor et al were unable to distinguish between the finest wool fibre (16.5um) and cotton [30], but the three wool types (16.5, 18.5, 20.5um; single jersey) were distinguishable by both an expert and an untrained panel. Most participants (~70%) preferred the cotton and two finer wools. Thus fabrics manufactured from finer fibres are perceived to have less prickle and are preferred.

2.1.5. Development, retention, and release of human body odour

Odour development, retention, and release of odour volatiles from fabrics continue to be relevant for manufacturers and end users [31]. Full understanding the mechanisms of adsorption, absorption, and release of the volatiles has not yet been achieved, however, wool fabrics are known to perform well in this regard, with intensity of odour from wool fabrics consistently lower than that of cotton and of polyester fabrics (three matched fabrics structures) [32, 33]. Microbial growth and odour development in cotton and synthetic fitness clothing (cotton, polyester, blend of cotton with other fibres) showed polyester to be the most intensely odorous and the least pleasant, with fibre-related differences in organisms isolated [34].

Consumers with high disposable income seek 'athleisure' products (i.e. suitable for work, social activities, exercise) with assurance of minimal odour release [31]. Demand for personal protective equipment with minimal release of odour volatiles is also evident: wool in next-to-skin products offers advantages over fabrics from other fibre types such as cotton and polyester. Blending wool with cotton has the potential to enhance the performance of cotton alone. Finishing treatments can be applied to inhibit odour-forming organisms on cotton and other fabrics (e.g. bactericides, fungicides, bacteriostatics), but widespread use of antimicrobial treatments is questioned. The risk of odour being retained on apparel textiles is likely to increase as practices for washing clothes at a lower temperature and with less water are adopted [31].

2.2. Environmental implications

Perceptions of environmental implications of raw material production, processing, consumption, and end-of-life disposal of natural fibres, tend to be positive. More than 70% of US consumers considered natural fibres were better from an environmental perspective [35]: little is known of the extent to which these respondents, younger consumers

[36], and the general public, understand the fibre-textile complexity with respect to environmental and ethical issues

[37]. Cotton and wool as fibre sources are considered sustainable in that supply is renewable and disposal is through biodegradation. Even considering the requirement for water (e.g. in cotton production and in processing of most fibres), land, pesticides and insecticides, these fibre sources are relatively environmentally friendly when compared with matched products of man-made petroleum based fibres e.g. polyester and nylon [38]. Increased emphasis on environmental sustainability generally is evident at international fabric fairs [39].

Determining the sustainability of different fibre types depends on multiple factors and quantification of in-puts is challenging [40]. These include land, water, energy, pesticide and insecticide use (e.g. natural fibre production requiring demands on land ([41]; environmental effects of emissions [42]; lower comparative energy consumption

(cotton (60MJ/kg), wool (63MJ/kg), compared with acrylic (175MJ/kg) and nylon (138.65MJ/kg) [40]), high water consumption of cotton for irrigation (>3500L/kg compared to wool <100L/kg) [42]; high use of insecticides and pesticides in cotton production (~16 and 11% of world consumption respectively). In terms of cotton, resistant strains have been achieved through genetic modification, having a downward effect on insecticide and herbicide use, and increasing yield [43, 44], and some increase in insects [45]. Organic cotton fibre production is one way of reducing deleterious environmental effects, and promoting organics in consumer markets is evident (e.g. Patagonia (since 1996), Cornish Organic wool, Treslike Organic) [46]. GiTiBi Filati presented organic wool blends and organic cotton yarns at a recent fair of knitwear yarns [31]. Organic crops reportedly have a much lower yield (up to 60% less) compared to conventionally grown cotton, resulting in slower adoption of organic methods [42] (estimated as approximately 0.2% of total production in 2009 [47]. Use of sustainable cotton by several companies (e.g. IKEA, H&M) has been reported from a companies survey: none reported using 100% sustainable cotton, and ~1/3 scored very low or did not report sufficient information [48]. Establishing The Better Cotton Initiative (BCI) which in 2015, constituted around 12% of world cotton production, is evidence of attitudinal change [31]. Producing finer wool fibre (<20 um), desirable for next-to-skin applications, has been achieved through selective animal breeding [41]. Sheep are a source of both fibre and meat in many regions, so determining the cost of wool production to the environment is complex [41], and some consumers are also concerned with humane animal treatment (e.g. banning of mulesing in Australia and New Zealand) [49]. Disposal of products made of natural fibres is viewed as less damaging to the environment than comparable products of man-made fibres; wool is readily recyclable [40], and many man-made fibre based products are recycled [42]. Recent developments in the biodegradation of synthetic polymers are noted and include polyester polyurethane [50, 51] and polyethylene terephthalate [52], along with both naturally occurring bacteria present in soil [50, 53], and specifically engineered bacteria/enzymes [54] using polymers for energy and conversion of it to environmentally safe products.

2.3. Culture-bound preference for fibre types

Fibre and fabric-related preferences are known to be culture-bound [37, 55, 56]. Consumers in the USA, both men and women (79%, 77% respectively) prefer cotton and cotton blends for next-to-skin garments, responses largely unchanged since 2010 [35]. Most considered such clothing to be of better quality, and many consumers report being prepared to pay more for clothing made from natural fibres [38]. This association of natural fibres with high quality, often results in products of natural fibres being selected over man-made products, particularly in instances where there is no restriction of cost [57]; when comparing environmental issues related to cotton, silk, polyester [58]; when considering environmental awareness [59]; and effects of imagery surrounding cotton and wool, including reference to organic, eco-friendly, sustainable, and natural [60].

As noted Section 1, wool continues to account for a small proportion of the textile market [56]. Consumer perceptions of it in an Australian-based study are varied: positive perceptions of comfort, quality, versatility, and negative perceptions of itchy, heavy, traditional, expensive [56]; differences in perceptions among consumers in US and Australia; negative perceptions of animal welfare linked to wool [37]. Cotton is often perceived by US consumers as an environmentally-friendly fibre being natural, renewable and recyclable [38], with many consumers reportedly willing to pay a premium for cotton products, irrespective of use of water, insecticides and pesticides in production [38]. Selective breeding and genetic modification of cotton have been reported as successful [61], and differences in moisture vapour properties of fabrics knitted from different cotton varieties have been observed [19]. Cotton/wool blends appear to be the topic of few investigations of consumer perception: one on village hand craft cotton/wool double jersey fabrics [62]; the tactile property of cotton/wool wovens (75% cotton, 25% wool; 25% cotton, 75% wool; 50% cotton, 50% wool) compared with matched fabrics of wool/acrylic, wool/polypropylene, cotton/acrylic, cotton/polypropylene, acrylic/polypropylene), with the acrylic blends considered a viable substitute for natural fibres [63].

3. Summary and Conclusions

Wool and cotton blends considered desirable during the 19th and early-mid 20th century (e.g. Viyella™,

Clydella™, Dayella™ and later Colana® in Australia) have all but disappeared from the market. However, several

benefits accrue from blending cotton and wool, thus providing an opportunity for re-emergence of the high-end

sector niche. Benefits include

• Superior performance properties of blends compared with matched 100% wool and 100% cotton fabrics, i.e. wool increases the softness, resilience (resistance to creasing), thermal resistance, hygroscopicity, and odour resistance of fabric; cotton enhances a 'cool' feeling and contributes to already hygroscopic wool; good tactile, thermal, moisture, and odour retention properties are desirable for next-to-skin products.

• Enhanced environmental effects compared to blends involving petroleum-based fibres, notwithstanding some desirable properties achieved by blending with polyester or polyamide (e.g. improved resistance to abrasion and to creasing).

• Favourable consumer perceptions of cotton, wool, and cotton/wool garments, as being of better quality and more sustainable than comparable garments manufactured from man-made fibres.

• Wool and to a lesser extent cotton, having superior properties of adsorption, absorption and release of odour volatiles from fabrics when compared with other fibre types commonly worn nest to the skin.

• Blending wool with cotton as a promising solution to reduced washing frequency and increased wear time, and compatible with lifestyle changes among consumers.

Acknowledgements

Ms Sophie Wilson gratefully acknowledges the Summer Scholarship 2016-2017 from the University of Otago,

Centre for Materials Science and Technology.

References

1. Laing, R.M. and P. Swan, Wool in human health and well-being, in Natural Fibres - Advances in Science and Technology Towards Industrial Applications, R. Fangueiro and S. Rana, Editors. 2016, Springer: Netherlands. p. 19-34

2. Textiles Intelligence Ltd, Global trends in fibre prices, production and consumption. Textile Outlook International, 2016. 182: p. 50.

3. Laing, R.M. and G.G. Sleivert, Clothing, textiles and human performance. Textile Progress, 2002. 32(2): p. 1-132.

4. Pascoe, D., L. Shanley, and E. Smith, Clothing and exercise I: biophysics of heat transfer between the individual, clothing and the environment. Sports Medicine, 1994. 18(1): p. 38-54.

5. Cookson, P. Natural fibre blends of cotton and wool. in 10th Australian Cotton Conference - Cotton - Meeting the Challenge. 2000. Australian Cotton Growers Research Association.

6. The Indian Express. Sportswool to make a mark in India in October 1999 24 March 2017].

7. Stuart, I.M., A.M. Schneider, and T.R. Turner, Perception of the heat of sorption of wool. Textile Research Journal, 1989. 59(6): p. 324-329.

8. Kwon, A., et al., Physiological significance of hydrophylic and hydrophobic textile materials during intermittent exercise in humans under the influence of warm ambient temperature with and without wind. European Journal of Applied Physiology and Occupational Physiology, 1998. 78(6): p. 487-493.

9. Vokac, Z., V. Kopke, and P. Keul, Physiological responses and thermal, humidity, and comfort sensations in wear trials with cotton and polypropylene vests. Textile Research Journal, 1976. 46(1): p. 30-38.

10. Grujic, D. and J. Gersak, Examination of the relationships between subjective clothing comfort assessment and physiological parameters with wear trials. Textile Research Journal, 2016. in press(on line 25 November 2016).

11. Laing, R.M. and P.E. Ingham, Patterning of objective and subjective responses to heat protective clothing systems part 1 objective measurements of comfort. Clothing and Textiles Research Journal, 1984. 3(1): p. 24-33.

12. Laing, R.M. and P.E. Ingham, Patterning of objective and subjective responses to heat protective clothing systems part 2 subjective measurements of comfort. Clothing and Textiles Research Journal, 1985. 3(2): p. 31-34.

13. Barkley, R.M., et al., Physiological versus perceived foot temperature, and perceived comfort, during treadmill running in shoes and socks of various constructions. American Journal of Undergraduate Research, 2011. 10: p. 7-14.

14. Kaplan, S. and A. Okur, Determination of coolness and dampness sensations created by fabrics by forearm test and fabric measurements. Journal of Sensory Studies, 2009. 24(4): p. 479-497.

15. Van Roekel, N.L., E.M. Poss, and D.S. Senchina, Foot temperature during thirty minutes of treadmill running in cotton-based versus olefin-based athletic socks. BIOS, 2014. 85(1): p. 30-37.

16. Herring, K.M. and D.H. Richie, Comparison of cotton and acrylic socks using generic cushion sole design for runners. Journal of the American Podiatric Medical Association, 1993. 83(9): p. 515-522.

17. Behera, B.K. and R. Mishra, Comfort properties of non-conventional light weight worsted suiting fabrics. Indian Journal of Fibre and Textile Research, 2007. 32(1): p. 72-79.

18. Bel, P.D. and G.L. Louis, A wool/cotton blend fabric made with scoured wool processed through the carding cleaner. Textile Research Journal, 1984. 54(12): p. 850-854.

19. Ramkumar, S.S., et al., Relationship between cotton varierties and moisture vapor transport of knitted fabrics. Journal of Engineered Fabrics and Fibres, 2007. 2(4): p. 10-18.

20. Ozdil, N., et al., A study on the moisture transport properties of the cotton knitted fabrics in single jersey structure. Tekstil ve Konfeksiyon, 2009. 3: p. 218-223.

21. Oglakcioglu, N., et al., Thermal comfort properties of angora rabbit/cotton fiber blended knitted fabrics. Textile Research Journal, 2009. 79(10): p. 888-894.

22. Filingeri, D., N.B. Morris, and O. Jay, Warm hands, cold heart: progressive whole-body cooling increases warm thermosensitivity of human hands and feet in a dose dependent fashion. Experimental Physiology, 2017. 102(1): p. 100-112.

23. Filingeri, D., H. Zhang, and E.A. Arens, Characteristics of the local cutaneous sensory thermo-neutral zone. Journal of Neurophysiology, 2017. in press(on line February 2017).

24. Plante, A.M., B.V. Holcombe, and L.G. Stephens, Fiber hygroscopicity and perceptions of dampness part l: subjective trials. Textile Research Journal, 1995. 65(5): p. 293-298.

25. Laing, R.M., et al., Differences in wearer response to garments for outdoor activity. Ergonomics, 2008. 51(4): p. 492-510.

26. McGregor, B.A., et al., The influence of fiber diameter, fabric attributes and environmental conditions on wetness sensations of next-to-skin knitwear. Textile Research Journal, 2015. 85(9): p. 912-928.

27. Wang, G., et al., Evaluating wool shirt comfort with wear trials and the forearm test. Textile Research Journal, 2003. 73(2): p. 113-119.

28. Kenins, P., Influence of fiber type and moisture on measured fabric-to-skin friction. Textile Research Journal, 1994. 64(12): p. 722-728.

29. Cameron, B.A., et al., Effect of natural and synthetic fibers and film and moisture content on stratum corneum hydration in an occlusive system. Textile Research Journal, 1997. 67(8): p. 585-592.

30. Naylor, G.R., J.H. Stanton, and J. Speijers, Skin comfort of base layer wool garments. Part 2: Fiber diameter effects on fabric and garment prickle. Textile Research Journal, 2014. 84(14): p. 1506-1514.

31. Textiles Intelligence Ltd, Textile outlook international: business and market analysis for the global textile and apparel industries. November 2016 ed. Vol. No 182. 2016, United Kingdom: Alderley House.

32. McQueen, R.H., et al., Retention of axillary odour on apparel fabrics. Journal of The Textile Institute, 2008. 99(6): p. 515-523.

33. McQueen, R.H., et al., Odor intensity in apparel fabrics and the link with bacterial populations. Textile Research Journal, 2007. 77(7): p. 449-456.

34. Callewaert, C., et al., Microbial odor profile of polyester and cotton clothes after a fitness session. Applied and Environmental Microbiology, 2014. 80(21): p. 6611-6619.

35. Bellomy Research. http://lifestylemonitor.cottoninc.com. 2015 8 December 2016].

36. Hill, J. and H.H. Lee, Young generation Y consumers' perceptions of sustainability in the apparel industry. Journal of Fashion Marketing and Management: an International Journal, 2012. 16(4): p. 477-491.

37. Sneddon, J.N., G.N. Soutar, and J.A. Lee, Exploring wool apparel consumers' ethical concerns and preferences. Journal of Fashion Marketing and Management, 2014. 18(2): p. 169-186.

38. Ha-Brookshire, J.E. and P.S. Norum, Willingness to pay for socially responsible products: case of cotton apparel. Journal of Consumer Marketing, 2011. 28(5): p. 344-353.

39. Textiles Intelligence Ltd, Textile outlook international: business and market analysis for the global textile and apparel industries. January 2016 ed. Vol. No 178. 2016, United Kingdom: Alderley House.

40. Muthu, S.S., et al., Quantification of environmental impact and ecological sustainability for textile fibres. Ecological Indicators, 2012. 13(1): p. 66-74.

41. Russell, I.M., Sustainable wool production and processing, in Sustainable Textiles: Life Cycle and Environmental Impact, R. Blackburn, Editor. 2009, Elsevier: Cambridge England. p. 63-85.

42. Fletcher, K., L. Grose, and P. Hawken, Fashion and Sustainability: Design for Change. 2012, London: Laurence King.

43. Jiang, C.X., et al., Polypoid formation created unique avenues for response to selection in Gossypium (cotton). Proceedings of the National Academy of Sciences, 1998. 95(8): p. 4419-4424.

44. Marvier, M., et al., A meta-analysis of effects of Bt cotton and maize on nontarget invertebrates. Science, 2007. 316(5830): p. 1475-1477.

45. Burkitbayeva, S., M. Qaim, and J. Swinnen, A black (white) hole in the global spread of GM cotton. Trends in Biotechnology, 2016. 34(4): p. 260-263.

46. Chouinard, Y. and M.S. Brown, Going organic: converting Patagonia's cotton product line. Journal of Industrial Ecology, 1997. 1(1): p. 117-129.

47. Grose, L., Sustainable cotton production, in Sustainable Textiles: Life Cycle and Environmental Impact, R. Blackburn, Editor. 2009, Elsevier. p. 33-60.

48. Dziamki, M. and R. van Delft, Sustainable Cotton Ranking: Assessing Company Performance, B. Jefferies, Editor. 2016, Rank a Brand: San Francisco: USA.

49. Sneddon, J.N. and B. Rollin, Mulesing and animal ethics. Journal of Agricultural and Environmental Ethics, 2010. 23(4): p. 371-386.

50. Khan, S., et al., Biodegradation of polyester polyurethane by Aspergillus tubingensis. Environmental Pollution., 2017. in press(on line 15 March 2017): p. http://dx.doi.org.ezproxy.otago.ac.nz/10.1016/j.envpol.2017.03.012.

51. Schmidt, J., et al., Degradation ofpolyester polyurethane by bacterial polyester hydrolases Polymers, 2017. 9(2): p. 65-74.

52. Yoshida, S., et al., A bacterium that degrades and assimilates poly (ethylene terephthalate). Science, 2016. 351(6278): p. 1196-1199.

53. Shah, Z., et al., Degradation of polyester polyurethane by an indigenously developed consortium of Pseudomonas and Bacillus species isolated from soil. Polymer Degradation and Stability, 2016. 134: p. 349-356.

54. Wei, R., et al., Engineered bacterial polyester hydrolases efficiently degrade polyethylene terephthalate due to relieved product inhibition. Biotechnology and Bioengineering, 2016. 113(8): p. 1658-1665.

55. Starick, L., Global fabric tracker study. 2013, Australian Wool Innovation in association with Nielsen: Sydney, Australia.

56. Sneddon, J.N., J.A. Lee, and G.N. Soutar, Exploring consumer beliefs about wool apparel in the USA and Australia. Journal of The Textile Institute, 2012. 103(1): p. 40-47.

57. Hatch, K.L. and J.A. Roberts, Use of intrinsic and extrinsic cues to assess textile product quality. Journal of Consumer Studies and Home Economics, 1985. 9(4): p. 341-357.

58. Forsythe, S.M. and J.B. Thomas, Natural, synthetic and blended fiber contents: an investigation of consumer preferences and perceptions. Consumer and Textiles Research Journal, 1989. 7(3): p. 60-64.

59. Ali, S., Analysis of consumer perception about eco-friendly apparel, in Materials Engineering. 2015, Tampere University of Technology. p. 100.

60. Bide, M., Fiber sustainability: green is not black + white. AATCC review, 2009. 9(7): p. 34-37.

61. Anderson, D.M. and K. Rajasekaran, The global importance of transgenic cotton, in Fiber Plants, K.G. Ramawat and M.R. Ahuja, Editors. 2016, Springer International Publishing: Switzerland. p. 17-33.

62. Sharma, M., S. Pant, and D.B. Shakyawar, Development of cotton: wool knitwears on khadi system and evaluation of their acceptability. International Journal of Home Science, 2016. 2(1): p. 9-12.

63. Overvliet, K.E., E. Karana, and S. Soto-Faraco, Perception of naturalness in textiles. Materials and Design, 2016. 90: p. 1192-1199.