Effect of glycols and catalysts on cotton fabrics treated with glyoxal

The optimum conditions for durable press treatment of cotton fabrics using glyoxal as a nonformaldehyde crosslinking agent were investigated. Crosslinking reaction was conducted in the presence of different catalysts such as aluminum sulfate, magnesium chloride, or magnesium chloride-citric acid mixture at various mole ratios of catalyst to glyoxal. Aluminum sulfate was proven the most effective one among those used. Glycol addition into a glyoxal padding bath increased the wrinkle recovery angle(WRA) and whiteness of treated fabrics. The optimum mole ratio of glycol to glyoxal was 1:1. Diethylene glycol addition produced better overall performance to the glyoxal-crosslinked fabric compared to ethylene glycol addition.     

Durable press finish of cotton via dual curing using UV light and heat

Continuous photografting/crosslinking of polyethyleneglycol dimethacrylate oligomers onto cotton using a water-soluble benzophenone photoinitiator was investigated. Photografting increased with increasing irradiation dose, oligomer concentration and photoinitiator concentration. Maximum grafting efficiency of DM 400 and 600 were 83% and 79%, respectively. The photografting increased the wrinkle resistance of cotton implying surface crosslinking of cotton. Both surface crosslinking and bulk crosslinking of cotton were accomplished via dual curing of a mixed formulation containing both a thermally curable component (BTCA/SHP) and a UV-curable component. The wrinkle resistance of the crosslinked cotton was found to be higher when cured by thermal curing after UV curing rather than by UV curing after thermal curing due to the facile post-polymerization of the UV active component. The presence of crosslinks in the dually crosslinked cotton was verified with FT-IR and thermogravimetric analysis.     

Durable press finish of cotton fabric using malic acid as a crosslinker

It has been considered that malic acid,α-hydroxy succinic acid, could not form crosslinks in the cellulosic materials unless activated by other polycarboxylic acids such as butanetetracarboxylic acid or citric acid because there are only two carboxylic acids per molecule available for the formation of one anhydride intermediate. However we found that the dicarboxylic malic acid with sodium hypophosphite catalyst without the addition of other crosslinkers was able to improve wrinkle resistance of cotton up to 294° (dry WRA) and 285° (wet WRA), which is a measure of crosslinking level in cotton.¹H FT-NMR, FT-IR and GPC analysis indicated the in-situ formation of an trimericα, β-malic acid with a composition of 1:3 through the esterification between hydroxyl group and one of carboxylic groups in malic acid during curing. The crosslinking of cotton was attributed to the trimericα, β-malic acid, a tetracarboxylic acid, which can form two anhydride rings during curing. The influence of crosslinking conditions such as concentrations of malic acid and catalyst, pH of the formulation bath, and curing temperature were investigated in terms of imparted wrinkle resistance and whiteness. The addition of reactive polyurethane resin in the formulation slightly increased the mechanical strength retention of crosslinked fabric coupled with additional increase in wrinkle resistance.     

A cross-cultural comparison of image perception and preferences for cotton fabrics between Korea and the United States

The purpose of this research was to perform an international comparison of image perception and preferences for cotton fabrics, specifically examining the inter-cultural differences that exist between Koreans and Americans. Respondents were asked to rate 55 different fabrics, produced in Korea, relative to eight different characterizations: feminine, masculine, casual, classic, new, old, ambiguous and orderly. Then they were asked to rate their level of preference for each fabric, using 7-point scales. Both Koreans and Americans evaluated thin and soft fabrics with pale colors high relative to feminine image and evaluated slightly thick, coarse and stiff fabrics with low chromatics high relative to masculine image. However, Koreans tended to categorize fabrics as feminine or masculine using color characteristics, while Americans tended to use surface characteristics. For the casual image, Denim and Chambray were rated highly, both in Korea and in the US. There were no fabrics which both countries rated highly for the classic image. New image was rated significantly above average in Korea, but average in the US. The old image perceptions fell below average in both countries. Most fabrics were evaluated above average with respect to being orderly, but fell below the average for ambiguous image, both in Korea and the US. Koreans showed higher preferences for the chosen fabrics than Americans, but the preference tendencies were similar in the two countries.