Sundry Organic Builders

The carboxymethyl cellulose (CMC) derivatives and carboxymethyl starch (CMS) are effective antiredeposition agents that are cellulose-containing fibers such as cotton and blends of cotton and synthetic fibers. However, CMC has virtually no effect on pure synthetic fibers. Other effective antiredeposition agents and soil repellents have been developed (Fig. 5.4) [20]. 

The nonionic cellulose ethers have been found suitable for use with synthetic fibers [3, 4]. 

The modern detergents are provided with mixtures of anionic and nonionic polymers (e.g., carboxymethylcellulose-methylcellulose) and also with polymers from polyethylene glycol and terephthalic acid [3, 4]. 

Optical brighteners are usually derivatives of coumarin, stilbene, dis-tyrylbipheny, and bis(benzoxazole). Examples of chemical structures of some important optical brighteners are given  

Chelating agents. The role of the chelating agents is to block the polyvalent ions and to make them undetectable and ineffective. Sodium salts of ethylene diamine tetraacetic acid (EDTA) and of nitrilo triacetic acid (NTA) are members of the group of chelating agents and their use has increased in the last few years. 

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