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A report is presented on a new cellulose cross-linking agent that is completely resistant to chlorine and durable to all types of laundering.A comparison of the performance of this compound, bis(β-hydroxyethyl) sulfone, with the more conventional type cross-linker is made.The problems posed by various conditions of laundering are also discussed as they affect fabric performance. FOR OX'ER twenty years now the problem of chlorine damage to resin-treated cellulosic fabrics has existed. I)uring the last five years publications on the subject have increased markedly [2, 3, 5-7, 9-12, 1-I J . As was pointed out by Nuessle ten years ago [ 7 however, the number of consumer complaints due to chlorine retention is fantastically small when one considers the millions of yards of resin-treated cloth sold each year. The same situation appears to exist today.Until fairly recently, essentially all resin-treated cottons have used poly-functional N-methylol compounds, such as urea-formaldehycle, methylol melamines, and climethylol ethylene urea (DMEU). It is generally recognized that most N-methylol compounds, particularly after a laundering or two, will retain chlorine when exposed to a solution of hypochlorite, and consequently the treated fabric can be degraded by the hydrochloric acid evolved at temperatures used in ironing.Another shortcoming of the N-methylol type of cross-linking agent is its lack of durability to washing. For some uses this type of product is considered satisfactory, hut for those garments which can be expected to get a rigorous laundering the N-methylol compounds will not give practical washand-wear performance.The reaction of this type of cross-linker may be expressed as This equation shows that with acid and heat a hyclroxyl group on one cellulose chain is tied through the reactant to the hydroxyl group of another cellulose chain with the evolution of water. The reaction is pushed to completion during curing by eliminating the water as it is formed. Since the reaction is reversible, in the presence of water and acid the cross-links are hydrolyzed. To prevent this reversal most resin suppliers urge their customers to afterwash their treated fabric to remove the acid catalyst, and for this reason fabric that is not afterwashed often smells of formaldehyde, particularly in hot, humid weather.To increase the usefulness of wash-and-wear finishes the problems of chlorine retention and poor durability must be overcome. The triazone type resin, with an acid neutralizing group built into the molecule, appears to have solved the problem of chlorine damage. The triazone still retains chlorine, but extreme tensile losses .do not occur in the accelerated chlorine retention test. Another approach is to build an N-methylol compound which either does

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