GB425475A - A process for improving wool - Google Patents

Abstract

Wool, which has been washed to remove grease, is subjected to a mild treatment insufficient to affect its dyeing properties with fatty acids or halogen-substituted fatty acids containing up to 5 carbon atoms in the molecule, or with the anhydrides of such acids, in all cases substantially in the absence of water. Wool, cardings or yarn, spun, knitted or woven in the raw, bleached or dyed condition may be used. Suitable acids which are specified are formic, acetic, and chlorinated acetic acids, and acetic, propionic and chlorinated acetic anhydrides, and the acids may be employed in a liquid form, but preferably in organic solvents, e.g. benzene, and carbon tetrachloride avoiding solvents containing oxygen. The material may be soaked in the solution, dried and aerated, or may be treated with the reagent in gaseous form, or a combination of these methods may be employed, and the treatment may be combined with a water-proofing treatment by the action of anhydrides of higher fatty acids. According to examples: (1) German shearing wool previously washed is treated with a solution of formic acid in benzene, dried and aerated; raw carded yarn is similarly treated; (2) acid dyed carded yarn is treated with a solution of glacial acetic acid in benzene, followed by drying and aerating; (3) raw carded yarn is treated with formic acid in carbon tetrachloride or, trichloracetic acid in benzene; (4) raw carded yarn is treated with acetic anhydride in benzene; acid dyed cloth is similarly treated; (5) dyed carded yarn is exposed to formic acid vapour followed by aeration or neutralization with ammonia; (6) washed carded wool in flock or undyed form is similarly treated.