GB795674A - Stabilised soap compositions - Google Patents

Abstract

Compounds of the formula R3CONHNR1R2, in which R1 is alkyl, R2 is hydrogen or alkyl, R3 is alkyl, aryl or aralkyl, and the alkyl groups may be saturated, unsaturated or substituted by hydroxyl, alkoxyl, carboxyl or sulphonic acid radicals, are prepared by (a) interaction of an ester and an appropriately substituted hydrazine, preferably under pressure when any of the alkyl groups is methyl; (b) interaction of an acyl chloride and a substituted hydrazine in the presence of a tertiary base such as pyridine; (c) alkylation of the monohydrazide R3CONHNH2. Compounds of the formula RCONHNHCOR, where the groups R are identical alkyl groups, are prepared by (d) prolonged heating of the monohydrazide RCONH NH2; (e) prolonged heating of the ester RCOOEt with hydrazine; (f) interaction of RCONHNH2 with RCOOEt; (g) interaction of RCONHNH2 with RCOCl in the presence of a tertiary base; (h) interaction of RCONHNH2 with iodine in absolute alcohol. Specified products are N-methyl-N1-lauroyl hydrazine, N-(b - hydroxyethyl) - N1 - lauroyl hydrazine, N : N1 - dilauroyl hydrazine, N : N - dimethyl-N1 - benzoyl hydrazine and N - (b - hydroxyethyl)-N1-acetyl hydrazine.ALSO:Soap compositions contain a stabilizing compound, usually in amounts up to 5 per cent, and preferably 0.1-1.0 per cent, having the formula R3-CO-NH-NR1R2, where R1 is an alkyl or acyl radical, preferably of not more than 4 carbon atoms, R2 is hydrogen or an alkyl or acyl radical, R1 and R2 may be connected to form a ring or either of them may be linked to R3 to form a ring, and R3 is an alkyl, aralkyl or aryl radical containing up to 18 carbon atoms, but preferably not more than 12. The alkyl or acyl radicals may be saturated or unsaturated and may be substituted by hydroxyl, alkoxyl, aryl, carboxyl or sulphonic radicals or their salts. R3 may be further substituted by the group -CO-NH-NR1R2. In preferred compounds R1 contains 1 or 2 carbon atoms, R2 is hydrogen and R3 is a straight chain alkyl, or aryl radical. The compound may be incorporated at any stage of the manufacture of soap, and in the case where R3 is fatty alkyl, may be produced in situ by treating the fat charge with the appropriate substituted hydrazine. Methods of preparing the hydrazides are outlined. The preferred hydrazide is N-(b -hydroxyethyl)-N1-acetyl hydrazine, but other compounds specified are N - methyl - N1 - lauroyl hydrazine, N - b -hydroxyethyl - N1 - lauroyl hydrazine, N,N1-dilauroyl hydrazine and N,N-dimethyl-N1-benzoyl hydrazine. The compositions, which may be produced in powder, flake, granular or tablet form, may also include rosin, perfume, opacifiers, whitening agents, and dyes.