LEATHER MANUFACTURE PROCESS Russian patent published in 1999 - IPC

FIELD: leather industry. SUBSTANCE: invention relates to leather for manufacture of shoe uppers from cattle hides. Intermediate product is preliminarily partially tanned with chrome tanner and treated with 2-5% of chitosan, after which material is dyed and dubbed. Then final tannage is carried out with 2 to 5% of chitosan and chrome tanner, the latter being added 25-45 min after addition of chitosan. EFFECT: increased softness and elasticity of leather in combination with deeper saturated coloration of its face. 1 tbl, 5 ex