Wrinkle resistance

The performance of a textile fabric is characterized by terms such as strength, hand, drape, flexibiUty, moisture transport, and wrinkle resistance. Although the interactions among fibers in a fabric array are complex, its properties reflect in part the inherent properties of the fiber as well as how the fibers are assembled. 

Polymers. AH nitro alcohols are sources of formaldehyde for cross-linking in polymers of urea, melamine, phenols, resorcinol, etc (see Amino RESINS AND PLASTICS). Nitrodiols and 2-hydroxymethyl-2-nitro-l,3-propanediol can be used as polyols to form polyester or polyurethane products (see Polyesters Urethane polymers). 2-Methyl-2-nitro-l-propanol is used in tires to promote the adhesion of mbber to tire cord (qv). Nitro alcohols are used as hardening agents in photographic processes, and 2-hydroxymethyl-2-nitro-l,3-propanediol is a cross-linking agent for starch adhesives, polyamides, urea resins, or wool, and in tanning operations (17—25). Wrinkle-resistant fabric with reduced free formaldehyde content is obtained by treatment with... 

Qiana, introduced by Du Pont in 1968 but later withdrawn from the market, was made from bis(4-aminocyclohexyl)methane and dodecanedioic acid. This diamine exists in several cis—trans and trans—trans isomeric forms that influence fiber properties such as shrinkage. The product offered silk-like hand and luster, dimensional stabiUty, and wrinkle resistance similar to polyester. The yam melted at 280°C, had a high wet glass-transition temperature of - 85° C and a density of 1.03 g/cm, the last was lower than that of nylon-6 and nylon-6,6. Qiana requited a carrier for effective dyeing (see Dye carriers). 

Other polyamides having higher moduli and T than nylon-6 and nylon-6,6 have been evaluated in an effort to reduce wrinkle resistance and eliminate flat-spotting of bias and bias-belted tires (Table 3). Nylons have also been tested extensively over the years for apparel and carpets (Table 4). 

Phenylenediamines are used in a variety of other appHcations, such as corrosion inhibitors, cross-linking agents for epoxy resins, toners for electrostatic image development (35), and to improve wrinkle resistance of cellulose acetate fibers (36). 

Like methylolureas, cycHc ureas are based on reactions between urea and formaldehyde however, the amino resin is cycHc rather than linear. Many cychc urea resins have been used in textile-finishing processes, particularly to achieve wrinkle resistance and shrinkage control, but the ones described below are the most commercially important. They ate all in use today to greater or lesser extents, depending on specific end requirements (see also Textiles, finishing). 

Resilience of textile fabrics when compressed in the bent state is related to wrinkle resistance and retention of shape, drape, and hand. Resilience is an important parameter for evaluating blankets, wearing apparel in which warmth is a factor, pUe fabrics including carpets, and bulk fiber utilization in mattresses, cushions, etc. The general method for determining compressional resilience is to compress and unload the material cycHcahy, creating a plot of compressive force versus fabric thickness. 

Grease Retention, Wrinkle Resistance, and Durable Press. On bending or creasing of a textile material, the external portion of each filament in the yam is placed under tension, and the internal portion is placed in compression. Thus, the wrinMe-recovery properties must be governed in part by the inherent, tensional elastic deformation and recovery properties of the fibers. In addition to the inherent fiber properties, the yam and fabric geometry must be considered. 

Textiles. Citric acid acts as a buffer in the manufacture of glyoxal resins which are used to give textiles a high quaUty durable-press finish (see Amino resins). It has been reported to increase the soil-release property of cotton with wrinkle-resistant finishes and is used as a buffer, a chelating agent, and a non-volatile acid to adjust pH in disperse dying operations (182—193). 

Wrinkle resistance, in fiber finishing, 22 593-594 Writing inks early, 14 311 water-based, 14 328 Wrought... 

A great part of the variation in the final properties of a textile is adjusted for by finishing procedures, for example, wrinkle resistance, soil repellence, hydrophobic properties, flame retardance, and antimicrobial properties [69]. In many cases chemicals are added by padding/ squeezing followed by drying/fixation, for example, in a stenter. 

Along with nylons, polyester fibers approach and exceed common natural fibers such as cotton and wool in heat stability, wash-and-wear properties, and wrinkle resistance. Blended textiles from polyester, cotton, and wool also can be made to be permanent-press and... 

The care of microfiber products is similar to that of the normal fiber materials made from the same polymer. One caution is heat sensitivity. Because the fibers are so fine, heat penetrates easily causing them to scorch or glaze more quickly than normal fibers if too much heat is applied or heat is applied over too long a period. Typically, microfibers are wrinkle-resistant, but if ironing is done, it should be accomplished using lower temperatures and only as directed. 

Cellulosic fibers (cotton, rayon) are crosslinked by reaction of the hydroxyl groups of cellulose with formaldehyde, diepoxides, diisocyanates, and various methylol compounds such as urea-formaldehyde prepolymers, /V, /V -di tnethylol-A(A -dimethy lene urea, and trimethyl-olmelamine [Marsh, 1966]. Crosslinking imparts crease and wrinkle resistance and results in iron-free fabrics. 

Cellulose acetate fibers are defined by the Textile Fiber Products Identification Act as manufactured fibers in which the fiber-forming substance is cellulose acetate in which not less than 92% of the hydroxyl groups are acetylated. Cellulose triacetate is employed to make many tricot fabrics and sportswear. Cellulose triacetate textile is shrink- and wrinkle-resistant and easily washed. 

It has already been implied that cellulose triacetate will not produce a thermoplastic, as its softening point cannot be reduced appreciably by plasticizers. It is used in solution processes, however, to produce films and libers. Triacetate films absorb less water than films of secondary cellulose acetate, and they arc therefore more dimensionally stable in environments where the humidity is not controlled. Triacetate fibers, with a similar resistance to water, impart to fabrics wrinkle resistance, dimensional stability, and the ability to dry rapidly. Under United Slates federal regulations, a filler must tic made from a cellulose acetate having... 

From the standpoint of use in textiles, cotton is rated excellent for hand (general feel, softness, drape), pilling resistance, and stability to repeated launderings. Cotton is rated good for abrasion resistance, strength, wash and wear performance, and wrinkle resistance. Resisiance to sunlight is rated only fair. Pressed-erease retention is rated poor. Safe-ironing temperature for most coiton fabrics is 425°F (2I9°C>. 

Flax fabrics (linen) have an excellent hand, fair abrasion resistance, fair pilling resistance, good stability to repeated launderings, fair sunlight resistance, excellent colorfastness. veiy poor wash and wear performance, and poor wrinkle resistance. 

The other major uses of acrylic latexes are in textile finishing (e.g., stain and wrinkle resistance), adhesives, and floor polishes and waxes. Adhesives are used in many applications, including pressure-sensitive tapes, contact adhesives, and construction adhesives for carpeting and floor tiles. Peelable labels and stamps probably got their start with the Post-it note, invented by Spencer Silver and Art Fry at 3M company many years ago. 

In the textile Industry, the term finishing Is used to denote the application of chemicals exclusive of coloring agents to Impart certain esthetic effects such as drape, handle or wrinkle resistance and to affect physical properties such as resistance to shrinkage, resistance to seam slippage or soil and stain resistance. 

Synthetic polymers are also a major contributor in the textile industry. Synthetic fibers show excellent strength properties, chemical resistance, wrinkle resistance, and abrasion resistance. These fibers also show some undesired properties such as hydrophobicity due to which they show wearing discomfort as perspiration cannot penetrate the fabric and lower the reactivity with chemical agents, which normally act as barrier to other finishing agents. These problems are due to the presence of hydrophobic groups on the surface of synthetic polymers. Therefore, surface modification of synthetic polymers is very necessary. 

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