GB788657A - Process for the fat-liquoring of chrome-tanned hides - Google Patents

Abstract

788,657. Fat-liquoring leather. BOEHME FETTCHEMIE GES. June 25, 1954 [June 27, 1953], No. 18641/54. Class 76. Chrome tanned hides are treated with a fatliquoring oil containing a masking agent which is an oil soluble partial ester or partial amide of a carboxylic acid containing 3 or more carboxyl groups, or phosphoric acid, with high molecular weight alcohols or amines, or a salt of said partial esters and partial amines. Acids specified are phosphoric, diadipic, citric, 1,2,3,4-butanetetracarboxylic, trimesic, mellitic, nitrilo-triacetic, and ethylene diamine-tetra-acetic acids, and water-soluble salts of such esters and amides. Examples of masking agents are the monododecyl ester of orthophosphoric acid, the mono-octadecyl ester of citric acid, the monododecyl ester of nitrilo-triacetic acid and the mono- and di-dodecyl esters of ethylene diamine tetra-acetic acid. Normally 2 to 20 per cent of such agents are incorporated in the fatliquoring oil. Examples relate to (1) a fatliquoring oil composed of 40 parts of sulphonated sperm oil, 40 parts of un-sulphonated sperm oil, and 10 parts of mineral oil to which was added 10 parts of the sodium salt of the monododecyl ester of ortho-phosphoric acid. 1.2 to 3.5 per cent of this composition was employed in about 200-250 per cent of liquor for the fat-liquoring of chromed tanned upper leather. (2) a fat-liquoring oil similar to (1) above contained 15 per cent of the cyclohexyl amine salt of the mono-oleyl ester of orthophosphoric acid as a masking agent, and was applied in an amount of 4-6 per cent to chromed tanned leather, the application being such that one-third of the fat-liquor oil was applied to the chromed-tanned and neutralized leather, followed by charging with 3-6 per cent of a vegetable tanning material, dyeing, and again fat-liquoring with the remainder of the fat-liquoring oil. (3) To the fat-liquoring oil of Examples (1) and (2) above 10 per cent of the ammonium salt of a mono-ester of citric acid was added in place of the masking agent mentioned. The fatty alcohol fraction used for the esterification consisted of coconut oil alcohols C 12 to C 18 chain length.