Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From protein or biologically active polypeptide reactant
Patent
1996-11-13
1998-02-03
Krass, Frederick
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From protein or biologically active polypeptide reactant
527202, 8 941R, 8 9418, 8 9419R, 8 9418C, 8 9433, C14C 322, C08F28900
Patent
active
057145601
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to the use of water-soluble or water-dispersible graft polymers of proteins which are obtainable by free-radical-initated polymerization of acrylic or methacrylic acid or salts thereof, if desired with further monomers, in the presence of proteins, as tanning agents in the production of leather and skins. The present invention furthermore relates to polymeric tanning agents based on these water-soluble or water-dispersible graft polymers.
In the production of leather, the main tanning is usually carried out using mineral tanning agents, such as basic chromium, aluminum and/or zirconium salts, or in combination with synthetic tanning agents. Subsequent retanning using natural or synthetic tanning agents serves to improve the leather properties, such as handle, softness, grain characteristics and body. Examples of tanning agents in retanning are syntans, i.e. water-soluble condensates of, for example, naphthylenesulfonic acid and formaldehyde or of phenolsulfonic acid, formaldehyde and urea, furthermore ligninsulfonic acids and also polymers and copolymers based on acrylic acid and other unsaturated polymerizable carboxylic acids, generally in combination with the abovementioned syntans.
For the production of leather and skins having a fine grain and uniform coloring, GB-A 2,074,173 (1) and GB-A 2,137,654 (2) describe terpolymers comprising from 5 to 25% by weight of nitrogen-containing (meth)acrylates, from 67 to 92% by weight of (meth)acrylates and from 1 to 8% by weight of (meth)acrylic acid as tanning agents. These can also be grafted to water-soluble proteins or polysaccharides in order to reduce their tack.
U.S. Pat. No. 4,812,550 (3) discloses a process for the preparation of grafted proteins in which ethylenically unsaturated monomers containing not more than 14 carbon atoms in the molecule are subjected to free-radical polymerization in an aqueous medium in the presence of solubilized proteins. Acrylic acid and methacrylic acid are not mentioned as monomers. The resultant lattices are used, for example, as binders for pigmented paper sizing agents. U.S. Pat. No. 3,651,210 (4) discloses that specific emulsion copolymers containing from 1 to 10% by weight of (meth)acrylic acid can be reacted with solubilized proteins, and the proteins modified in this way can be used, for example, for coating leather.
These agents of the prior art have a number of disadvantages. In particular they cause the color of the leather and skins produced in this way to become excessively pale. In addition, they give poor lightfastness and heat resistance. They also impart an undesired rubber-like handle to the leather.
It is an object of the present invention to provide the leather industry with tanning agents for the production of leather and furs which do not have said disadvantages.
We have found that this object is achieved by water-soluble or water-dispersible proteins which are obtainable by free-radical-initiated polymerization of mixture thereof or alkali metal, alkaline earth metal or ammonium salts thereof, which can be copolymerized with the monomers (a), and unsaturated, non-conjugated double bonds in the molecule, used as tanning agents for self-tanning, pretanning and assist tanning of leather pelts and skin pelts and for the retanning of leather and skins.
These water-soluble or water-dispersible graft polymers are thus obtainable by homopolymerization or copolymerization of the monomers A in the presence of the natural materials B.
Suitable monomers A from group (a) are (meth)acrylic acid and the alkali metal, alkaline earth metal and ammonium salts thereof. It is also possible to use mixtures thereof. These salts are obtainable, for example, from (meth)acrylic acid by neutralizing the acid in aqueous solution using sodium hydroxide solution, potassium hydroxide solution, lithium hydroxide solution, magnesium hydroxide solution, ammonia, amines or alkanolamines.
The monomers A from group (a) can, if desired, be subjected to the graft copolymerization together with other monoethyle
REFERENCES:
patent: 2205882 (1940-06-01), Graves
patent: 3651210 (1972-03-01), Shepler et al.
patent: 4314800 (1982-02-01), Monsheimer et al.
patent: 4812550 (1989-03-01), Erickson et al.
patent: 5425784 (1995-06-01), Denzinger et al.
Bernhardt Gunter
Denzinger Walter
Hartmann Heinrich
Kistenmacher Axel
Wolf Gerhard
BASF - Aktiengesellschaft
Krass Frederick
LandOfFree
Water-soluble or water-dispersible graft polymers of proteins as does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Water-soluble or water-dispersible graft polymers of proteins as, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Water-soluble or water-dispersible graft polymers of proteins as will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-663189