Rohm Gmbh

Firma Carl Freudenberg

Other

R/hm Gmbh

Universal Gesellschaft Fur Umwelttechnik Mbh

Rolf Monsheimer

Ernst Pfleiderer

Zdenek Eckmayer

Alexander Berg

Tilman Taeger

Max May

Klaus Braeumer

Werner Siol

Hans Trabitzsch

Hanns Boessler

Dietrich J Von Der Pahle

Eberhard Kreuzburg

What is disclosed is a process for the unhairing and subsequent curing of hides and skins, which comprises washing flayed skins and hides to remove adhering dirt, then soaking said skins and hides and freeing them of hair and scud with a short term unhairing, reversing the swelling of said skins and hides and neutralizing them, and curing said skins and hides with salt, said skins and hides being mechanically fleshed either after washing or at some later time in the process as recited.

Process for producing unhaired, storable hides and skins

What are disclosed are improved methods for the preparation of leather wherein, in one or more steps for preparing leather from limed animal skins or hides, including beamhouse operations such as deliming, bating, pickling, and degreasing to prepare unhaired tannable hides from animal skins or hides, and including subsequent tanning, retanning, and dyeing steps performed on said unhaired tannable hides, small amounts of a high polymeric water soluble cellulose ether or of an acrylic polymer are added to at least one of the treating baths involved in such method steps as a lubricant for said skins or hides.

Tanning method

A method and a device for converting and separating substances dissolved in a carrier fluid, more particularly proteides or proteins, by adding and mixing with an agent, e.g. enzymes, which brings about the chemical reaction or the build-up or breakdown of the molecules of the substances and causes them to precipitate. In addition these substances are mixed and come to an accelerated reaction with the agent in at least one circuit flow through a jet immersion reactor while a gas is supplied intensively thereto before froth flotation of the precipitated substances is carried out after adding means assisting flotation.

CRT Method of converting and separating substances contained, dissolved

What is disclosed are improved methods for the preparation of leather wherein, in one or more steps for preparing leather from animal skins or hides, including beamhouse operations such as soaking, dehairing, opening of the hide structure, deliming, bating, pickling, and degreasing to prepare dehaired tannable hides from animal skins or hides, and including subsequent tanning, retanning, and dying steps performed on said tannable hides, a thickening agent is added to at least one of the treating baths involved in such method steps.

What is disclosed is a method for liming animal skins and hides which comprises treating said skins and hides with an aqueous alkaline liming liquor comprising a protective colloid, for example a protein such as gelatin, glue, or casein, or a water-soluble alkali-stable polymethacrylate.

Process for liming pelts of animal hides and skins

What is disclosed is a method for soaking preserved skins or hides adaptable to the preparation of leather which comprises soaking said skins or hides in an aqueous bath containing a compound selected from the group of compounds of the formula ##STR1## and acid addition salts thereof, wherein R taken alone is --H, --NH.sub.2, --CH.sub.3, or --NHCN, X taken alone is .dbd.O, .dbd.S, or .dbd.NH, and R and X taken together form a five- or six-membered heterocyclic ring having conjugated double bonds and containing only nitrogen as a hetero atom.

Soaking method

What is disclosed are a method for treating pelts or leather in the beamhouse, for tanning, or as an aftertreatment, which method comprises contacting said pelts or leather with an aqueous solution or dispersion of a copolymer comprising monomers of a nitrogenous ester of acrylic acid or of methacrylic acid, a further different ester of acrylic acid or of methacrylic acid, and acrylic acid or methacrylic acid, whereby portions of said copolymer are deposited in the grain layer without formation of a superficial film, and pelts and leather treated by this method.

Method for treating pelts and leather

What is disclosed is a method for soaking dried or salted fur pelts which comprises soaking said pelts in an aqueous bath containing at least one compound selected from the group consisting of compounds of the formula ##STR1## and acid addition salts of such compounds, wherein R taken alone is --H, --NH.sub.2, --CH.sub.3, or --NHCN, X taken alone is .dbd.O, .dbd.S, or .dbd.NH, and R and X taken together form a five- or six-membered heterocyclic ring having conjugated double bonds therein and containing only nitrogen as a hetero atom.

What is disclosed is a method for the recovery of hair from an animal hide and for a concurrent opening of the hide structure using a proteolytic enzyme, which method comprises first pre-treating the hide, free of preservative salt, in the acid pH region with a material cleaving disulfide bridges and then, without a previous softening, concurrently loosening hair and opening the hide structure by treating said hide with a protease, effective in the alkaline region, at a pH value of about 11 to about 13.

Enzymatic method for hair recovery with concurrent opening of hide

What is disclosed is a method for dissolving collagen-containing tissues, such as the wastes arising in leather processing, which comprises enzymatically hydrolyzing said tissues with at least one acid protease at a pH within the acid region.

Method of dissolving collagen-containing tissues

What is disclosed is a method for soaking skins or hides which comprises soaking said skins or hides in an acid bath containing at least one compound selected from the group of compounds having one of the formulas

What is disclosed is a method for the enzymatic bating of pelts with simultaneous removal of scud, which method comprises bating said pelts in the acid pH range in the presence of an amylase and a protease.

Enzymatic bating method

A method is disclosed for making a water-soluble hydrolyzate of a keratinaceous starting material which comprises first subjecting said starting material to acid treatment at a pH of 2 or below and at an elevated temperature above 80.degree. C. to effect mild hydrolysis thereof and then enzymatically degrading said acid-treated material in an aqueous bath in the presence of urea with an alkaline proteinase having an activity optimum in a range between pH 9 and pH 13, the initial pH of the enzymatic treatment being within the pH range optimum for the enzyme employed.

Method for making water-soluble hydrolyzates of keratinaceous materials

A method for converting blood, animal parts, bone waste, or meat scraps into useful products, which method comprises hydrolyzing such a substrate with a proteinase, preferably in the presence of urea, in an aqueous hydrolysis medium at a pH in a region in which the proteinase displays sufficient activity, subsequently inactivating the enzyme, and working up the hydrolyzate.

Growing community of inventors

Darmstadt-Eberstadt, Germany

Rolf Monsheimer