| abstract |
Water-sol. alkali(ne earth) or Al salts of (in)organic anions, compatible with surfactants without pptn., are used in amt. of at least 2 (at least 5) wt., calc. as anhydrous salt, to preserve liq., aq. surfactant systems, free from preservative and contg. 2-50 (5-35) wt.% of surfactant(s). Pref. Mg salts of (in)organic acids, NaCl, Na2SO4, KCl, Na hexametaphosphate and/or AlCl3 are used, esp. MgCl2 and/or MgSO4 and/or Na hexametaphosphate, and partic. 4-30 (10-25) wt.% of MgCl2.6H2O. A self-preserving surfactant compsn. contains 2-50 (5-35)% of a combination of (a) 20-90 (67-75) wt.% of a sulphosuccinic acid semi-ester of formula R-(O-CH2CH2)n-O(O)- C-CH(SO3Na)-CH2-C(O)-ONa, (b) 9-79% (22-30%) of anionic surfactant(s), (c) 1-10% (205%) of amphoteric cpds., and (d) 0-5% (1-2%) of nonionic surfactant(s), and 2-25% of the salt(s). R = 7-17C alkyl or ricinol-alkyl; n = 2-4. |