METHOD OF LEATHER PROCESSING Russian patent published in 2012 - IPC C14C11/00 C14C13/00 C14B99/00 

FIELD: process engineering.

SUBSTANCE: proposed method comprises tanning, dyeing, oiling, drying, sorting semi-finished products into those with deep and shallow surface defects. Additionally, semi-finished products are processed laser liner radiation with wavelength of 1.064-1.075 mcm and power of 1.1-1.5 kW at processing speed of 8-10 m/min. After said additional processing, bottom composition is applied on semi-finished product with shallow defects that comprises, in wt %: 40%-water dispersion of methyl methacrylate copolymer, butyl acrylate, vinyl acetate and methacrylic acid at the ratio of 20:50:25:5, respectively 20-30, penetrator 5-7, and water of up to 100. Composition is applied on surface with deep defects that comprises the following components in wt %: pigment concentrator 7-9, 40%-water dispersion of butyl acrylate, acrylonitrile and methacrylic acid at the ratio of 70:25:5 respectively 35-45, wax emulsion 9-10, 10%-casein 7-8, mix of aminoparaffins containing 1-6 aminogroups and chlorinated paraffins at the ratio of 1:1-4-6, and water of up to 100. Obtained coatings are fixed by composition containing, in wt %: 40%-water dispersion of butyl acrylate and acrylonitrile copolymers at the ratio of 64:36 35-45, wax emulsion 3.5-4.5, 10%-casein 3,5-4,5, mix of aminoparaffins containing 1-6 aminogroups and chlorinated paraffins at the ratio of 1:1 3.5-4.5, and water of up to 100.

EFFECT: higher durability of leather from low-grade raw stock.

3 tbl, 1 dwg