Tanning process with metal salts and silicic salts

摘要

270,267. R÷hm & Haas Akt.-Ges. April 30, 1926, [Convention date]. Chrome, iron, and like mineral tanning; tanning with special chemicals.-In tanning with metallic salts together with salts of silicic acid, acids (or their salts) of greater valency than two are added. In addition, mono or divalent organic acids may be employed. Acids or their salts which are suitable for use in the mixture comprise boric, phosphoric, arsenic, and antimonic acids, and of organic acids acetic, lactic, oxali and salicylic acids. Tin salt may also be used. Examples: 1. An alkaline solution of waterglass is added to chrome alum and tin tetrachloride in aqueous solution. 2. A solution of an iron salt is mixed with phosphoric acid and a solution of waterglass is added. 3. A solution of waterglass is added to a solution of alum to which sodium phosphate and oxalic acid have been added. Tanning is carried out with the solution so obtained.