METHOD OF LEATHER TREATMENT Russian patent published in 2002 - IPC

FIELD: leather industry. SUBSTANCE: invention relates to method of treatment of leather of different designation. Intermediate product is neutralized with formate and sodium hydrocarbonate followed by additional tanning with product of condensation of naphthalene sulfoacid with formaldehyde and lignosulfonate taken in the amount 1.7-2.5% of semifinished product mass. Then staining is carried out in the presence of organic tanning agent taken in the amount 3-7% of semifinished product mass followed by greasing. Method ensures to obtain leather with high exploitation properties. EFFECT: improved method of treatment. 1 tbl, 5 ex