KR880010135A - Biologically stable and non-tanned leather and methods for obtaining these leathers - Google Patents

Abstract

These hides, completely free from chromium, have a moisture content of between 15 and 20%, a maximum inorganic matter content of 10 +/- 2%, an aluminium oxide content of 0.7 +/- 0.2% and an acrylic derivatives content of approximately 2%. Their pH is in the region of 4.0% and their dermic substance content is approximately 85 +/- 3%. They are capable of being rewetted in less than an hour. The process for obtaining them, of the type consisting in subjecting the completely delimed and bated hides to a pickling treatment in the presence of acrylic resin and then, after a rest, to a pretanning treatment with the aid of aluminium salts, is characterised in that there is introduced at any stage of the treatment a chemical agent facilitating the rewetting and enabling the hide to retain, after drying, a residual moisture close to 20% and in that the hide thus treated is subjected to drying. This chemical agent is chosen from the group consisting of polyalcohols, condensates of fatty alcohols with ethylene oxide and condensates of alkylphenols with ethylene oxide.

Description

Biologically stable and non-tanned leathers and methods for obtaining these leathers

As this is a public information case, the full text was not included.

Claims (20)

Rewet at least 1 hour with a water content of 15-20%, an organic content of 1-12%, an aluminum oxide content of 0.5-0.9%, a pH of about 4,0, a skin level of DIR 82-88% Biologically stabilized, chrome free, non-tanned clean leather. The leather of claim 1 further comprising 2% acrylic derivatives. The leather of claim 1 comprising a small amount of product selected from the group consisting of polyalcohols, condensation of spleen alcohols with ethylene oxide and condensation of alkylphenols with ethylene oxide. The method of claim 1, wherein the decalcified synthetically, the softened leather is acidified and the leather is upright, and the leather is pre-barbed with aluminum salt, wherein about 20% after promoting re-wetting and drying A chemical solvent for preserving the leather to maintain the true moisture of the method of obtaining the leather comprising the step of introducing any one of the above steps and drying the leather. The method of claim 4, wherein the acid treatment is led in the presence of an acrylic resin. A method of introducing a chemical solvent in the acid treatment step to promote rewet. 5. A method according to claim 4, wherein a chemical solvent which promotes rewet is introduced in a pretanning step. 5. A method according to claim 4, wherein a chemical solvent is introduced to promote acid treatment and tanning rewet. The method according to claim 4, wherein the chemical solvent for promoting rewet is selected from the group consisting of polyalcohols, condensation of fatty alcohols with ethylene oxide, condensation of alkylphenols with ethylene oxide. The method according to claim 4, wherein a ratio of 1% to 10% per weight of a chemical solvent for promoting rewet is also introduced. 5. The method according to claim 4, wherein an effective amount of an emulsifier representing a hydrophilic lipophilic resin determined in the same manner as the hydrophilic lipophilic resin required of the natural fatty substance is impregnated into the leather and the melting point of the preceding fatty substance in the presence of salt is fine. A subsurfactant which allows dispersion of the fatty material of the wave carried out at said temperature during rinsing in the form of an emulsion. The method of claim 11, wherein the relative proportions of the compounds used are as follows: Emulsifying agent… … … … … … … … … … … 30% to 70% Products that suck moisture ... … … … 20% to 60% Subsurfactant. … … … … … … … … … 5% to 15% Fungicides or fungicides… … … … … … 1% to 10% lubricant… … … … … … … … … … … … … 5% to 15% 13. The organic compound of claim 12, wherein the emulsifier is selected from the group consisting of octylphenol, nonylphenol, polyol, alcohol having a chain length of C ₈ to C ₁₈ atoms representing a hydratable lipophilic resin between 6 and 18 A method selected from the group consisting of oxyethyl compounds prepared by condensation with ethylene oxide or propylene oxide and mixtures thereof. 13. The method of claim 12, wherein the product that absorbs moisture is selected from the group consisting of glycerol, polyglycerol, sorbitol, trimethylol propane, polyethylene glycol and mixtures thereof and alkaline and alkaline-salts that absorb and dissolve moisture. . 13. The method of claim 12, wherein the subsurfactant is selected from the group consisting of alcohols, amines, glycols and amino alcohols. 13. The process of claim 12 wherein the fungicidal and bactericidal product is selected from the group consisting of quaternary ammonium salts in the form of trimethylcetyl ammonium. 13. The process of claim 12 wherein the lubricant is selected from the group consisting of aliphatic hydrocarbons having a chain length of C ₁₅ to C ₃₀ atoms. The method of claim 11 wherein the compound of the compound is introduced at a rate of 0.5% to 6% per weight of the leather. The method of claim 10 wherein the acid treated or pre-tanned leather is degreased, comprising a method comprising rinsing the leather with brine or hot water at a temperature of at least 20 ° C. The method of claim 4 wherein the hide is selected from the group consisting of cattle, sheep, goats, pigs, reptiles, birds, fish, amphibians and waterfowl. ※ Note: The disclosure is based on the initial application.