METHOD OF PRODUCING HEAT-RESISTANT LEATHER Russian patent published in 2018 - IPC C14C13/00 C14C1/06 C14C9/00 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to methods for production of special types of leathers and can be used in manufacture of heat-fast leathers for boots on passenger seats of various vehicles, mainly in cabins. Method for producing heat-fast leathers includes soak of raw materials, liming with trimethylamine oxide and polyhexamethyleneguanidine hydrochloride at its consumption of 0.3–0.5 % and 0.7–0.9 %, respectively by mass of row material, decalcification, mellowing, pickling, chroming, retanning of semi-products with chrome tanning agent, neutralization, a combined process of filling-greasing with melamine salt of bis (hydroxymethyl) phosphinic acid in amount of 0.2–0.4 % by mass of the semi-product, dyeing, processing with antipyrene the interreacting product of dimethyl methyl phosphonate, phosphoric acid, pentaerythritol and diethylenetriamine in a molar ratio of 1:(1–2):1:(1–2) at consumption of 18.0–20.0 % by mass of semi-product and an organic acid, wiring, drying and finishing of leather by breaking, staking, fixing of flesh side of a hide with water dispersion of acrylic polymer (40 %) and dust purging, applying pigmented coat, pressing, applying a composition of pigment finish and fixer. Composition of pigment finish has the following composition, mass%: pigment concentrate 10.0–12.0, aqueous dispersion of acrylic polymer (25 %) 50.0–60.0, aqueous dispersion of polyurethane (30 %) 3.0–5.0, aqueous dispersion of phosphorous-containing polyurethane (30 %) 12.0–14.0, silicone emulsion 1.0–2.0, melamine salt of bis (hydroxymethyl) phosphinic acid 0.5–0.7, water up to 100. Composition of fixer has the following composition, wt%: pigment concentrate 0.4–0.5, aqueous dispersion of polyurethane (22 %) 4.0–16.0, aqueous dispersion of phosphorous-containing polyurethane (30 %) 40.0–50.0, silicone emulsion 10.0–12.0, melamine salt of bis (hydroxymethyl) phosphinic acid 1.0–2.0, water up to 100. Fastening of flesh side of a hide is carried out at the expense of an aqueous dispersion of acrylic polymer (40 %) of 50–60 g/m².

EFFECT: proposed method for producing heat-resistant leather provides an increase in fire resistance and elasticity of leathers, as well as a decrease in their surface density while maintaining high physical and mechanical properties.

1 cl, 3 tbl, 6 ex