Finish, durable press, application

Essentially nonionic soil-release agents comprise polyesters, polyamides, polyurethanes, polyepoxides and polyacetals. These have been used mainly on polyester and polyester/ cellulosic fabrics, either crosslinked to effect insolubilisation (if necessary) or by surface adsorption at relatively low temperature. Polyester soil-release finishes have been most important, particularly for polyester fibres and their blends with cellulosic fibres. These finishes, however, have much lower relative molecular mass (1000 to 100 000) than polyester fibres and hence contain a greater proportion of hydrophilic hydroxy groups. They have been particularly useful for application in laundering processes. These essentially nonionic polymers may be given anionic character by copolymerising with, for example, the carboxylated polymers mentioned earlier these hybrid types are generally applied with durable press finishes. 

Substituted triazinyl derivatives of DAS are usually chosen for pad-dry-bake application to cotton in conjunction with an easy-care or durable-press finish. In these mildly acidic conditions (pH about 4) the FBA must show appreciable resistance towards the catalyst (usually magnesium chloride) necessary to cure the resin. The less substantive products in the upper half of Table 11.1 are important in this respect, as are compounds of type 11.9 where R = OCH3 or CH3NCH2CH2OH. It is likely that the hydroxyethylamino groups present in many of these compounds participate in condensation reactions with N-methylol groups in the cellulose-reactant resin. The performance of an FBA applied in conjunction with a resin finish can be modified and improved by careful formulation of the pad liquor but this lies beyond the scope of the present chapter. Alternatively, FBA and resin can be applied in two separate steps most DAST-type brighteners would be suitable if applied in this way. 

In commercial use, easy-care and durable press finishes are frequently combined with other finishes to provide additional properties such as water and oil repellency, flame retardancy, soil release and the like. Often the combination of another finish with the cellulose crosslinking finish will result in a more durable effect from the first finish. Combination with pigment printing is very common because of similar chemistry to cellulose crosslinking agents and binders and the similar application conditions. 

In addition to the desired repellency effects, other undesirable fabric properties are often found with repellent finishes. These include problems with static electricity, poor soil removal in aqueous laundering, stiffer fabric hand, greying (soil redeposition) during aqueous laundering and increased flammability. Some fabric properties that are often improved by repellent finishes include better durable press properties, more rapid drying and ironing, and increased resistance to acids, bases and other chemicals. Table 6.1 shows typical textile applications for repellent fabrics and their requirements. 

Permanent antistatic fmishes, based on crosshnked polyamines and polyglycols, need an alkaline catalyst. Therefore the one-bath combination with finishes, which need acid catalysis, is difficult but not impossible. Examples of acid-catalysed fmishes are the easy-care and durable press fmishes, durable hydrophylic silicone softeners and elastomeric finishes, also fluorocarbon-based repellency and some flame-retardant finishes. High finish effects result from a two-bath application with of the easy-care finish first followed by the surface-related antistatic finish. 

V. Fabric Finishing Application Durable Press Resin on Fabrics. 446... 

The versatility of rayons, coupled with their lower price, makes them suitable for many textile applications. Rayon is used in clothing and home furnishings. Disposable nonwoven garments and products of rayon have been introduced to the consumer in recent years. The stronger rayons have been used in tire cord for several decades but have lost a significant portion of this important market in recent years. Rayon has been used more and more in blends with synthetic fibers, since rayon undergoes less degradation than cotton with durable press and wash-and-wear finishes. 

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