Wrinkle-resistant fabrics are textiles that have been treated to resist external stress and hold their shape.
History
Cotton, rayon, and linen are fabrics that are highly absorbent therefore, wrinkle easily. Synthetics like polyester, nylon, acrylic and olefin, have greater stability since they do not absorb water as efficiently.[1] Wrinkle resistant treatments have been used since 1929, when cotton fabrics were treated with a solution of urea and formaldehyde. The solution forms a polymer resin inside the threads that makes the fabric thicker, making it wrinkle-resistant.[2] The textiles made from nylon and polyester are naturally wrinkle resistant,[2] and by 1950 fabrics made from these materials, and from treated cotton were described as “wash-and-wear” to point out that there was no need to iron them.[2] In the 1960´s and 1970´s, the developments in the chemistry of the treatments made possible the production of permanent-pressed fabrics, which today are known as durable-pressed finishes .[2] However, these processes weakened clothes; as a result, they wore out faster.[3]
Process
Cross-linking is the chemical process to produce textiles with wrinkle resistance.[4] Wrinkle resistance is achieved by the crosslinking of cellulose chains to stop the molecules from moving when in contact with water or other environmental stress.[5] Cotton cellulose polymer comprises three different regions: the crystalline region, the amorphous region, and an intermediate region between them. Although in the crystalline region the cellulose chains are closely arranged, limiting their mobility, chains in the amorphous and intermediate regions are bonded together by weaker bonds making them more susceptible to breaking.[1] There are two types of crosslinkers, which are the chemicals that bond together cellulose chains, the fist ones only bond cellulose chains, while the second self-polymerize resins as well.[5]
N-methylol and DMDHEU are reagents commonly used for the treatments because of their relatively low costs; however, they produce free formaldehyde,[1] which has been identified as a potential human carcinogen, and it can also cause harmful dermatological effects.[6] The use of titanium dioxide (TiO2) (as a catalyst/ co-catalyst for these reactions) has become an alternative way to minimize the formation of free formaldehyde and fabric strength loss.[1]
Dimethyloldihydroxyethyleneurea (DMDHEU) is the most commonly used durable-press finish. In this process, the chemical is first applied to the fabric. Then the fabric is heated to allow the chemicals to react with the cellulose molecules. In the reaction, the molecules of the fabric are bonded together to keep them from moving and causing wrinkles.[3][2] For this reason, durable-press treated garments behave as synthetics.[3] However, almost all the wrinkle resistant garments are made with poly/cotton blends fabrics.[7]
There are problems with the post-curing process, the final step of the treatment, because if the process is not done perfectly the garment gets damaged and can even turn yellow.[7] Companies have overcome the post-curing issues by producing wrinkle-resistant clothes using pre-cured fabrics.
Another solution
In the 2000´s, fabric softeners were launched to provide more resistant to external stress and wrinkle recovery,[6] which can be improved by spraying fabrics with aqueous emulsions (made with vegetable oils). The sprays allow the fibers to slide closer to each other, helping them hold their shapes. More over, this process is cheaper, simpler, and minimizes chemical waste, and water/energy consumption.[6] The anti-wrinkle sprays with higher concentration of the vegetable oil, which active agents are low in unsaturated fatty acids, are more effective.[6]
References
- ^ a b c d Lam, Y. L., Kan, C. W., & Yuen, C. W. (2011). Wrinkle-resistant finishing with dimethyloldihydroxyethyleneurea (DMDHEU) - the effect of co-catalyst. Textile Research Journal, 81(14), 1419-1426.
- ^ a b c d e Collier, Billie J. "Performance Finishes." Encyclopedia of Clothing and Fashion, edited by Valerie Steele, vol. 3, Charles Scribner's Sons, 2005, pp. 32-34. Gale Virtual Reference Library, go.galegroup.com/ps/i.do?p=GVRL&sw=w&u=itesm_mo&v=2.1&it=r&id=GALE%7CCX3427500451&asid=4abbf21886b76d07957d15835d0c15c8. Accessed 21 Apr. 2017
- ^ a b c DeWitt, J. W. (1994). Wrinkle-resistant redux. Apparel Industry Magazine, 55(3), 22. Retrieved from http://search.proquest.com/docview/215439347
- ^ Creating 'greener' wrinkle-resistant cotton fabric. (n.d.). Retrieved April 21, 2017, from https://www.acs.org/content/acs/en/pressroom/presspacs/2016/acs-presspac-january-27-2016/creating-greener-wrinkle-resistant-cotton-fabric.html
- ^ a b Dong, H. (2015). Formaldehyde-free wrinkle resistant treatment of cotton fabrics with novel aromatic polycarboxylic acids (Order No. 1604036). Available from ProQuest Dissertations & Theses Global. (1738859748). Retrieved from http://search.proquest.com/docview/1738859748
- ^ a b c d Stefanovic, B., Kostic, M., Bacher, M., Rosenau, T., & Potthast, A. (2014). Vegetable oils in textile finishing applications: The action mode of wrinkle-reduction sprays and means for analyzing their performance. Textile Research Journal, 84(5), 449-460.
- ^ a b Greco, M. (1995). Do WR shirts have a real future? Apparel Industry Magazine, 56(10), 40. Retrieved from http://search.proquest.com/docview/215438740