Bleaching and dyeing; fluid treatment and chemical modification – Treatment of hides – skins – feathers and animal tissues – Tanning
Patent
1997-11-12
1999-08-03
Diamond, Alan
Bleaching and dyeing; fluid treatment and chemical modification
Treatment of hides, skins, feathers and animal tissues
Tanning
8 9414, 8 9415, 8 9418, 8 9421, 427389, 252 857, C14C 900
Patent
active
059319704
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a process for treating hides and skins as well as tanned leather and fur with special surfactants to improve the water repellent action.
In the manufacturing process for waterproof leathers all hydrophilic substances are avoided to a large extent since they may impair the water repellent effect of ready-made leathers. In particular, these include salt-like compounds and surface-active substances, for example, surfactants. However, it is not possible to do completely without such wetting agents, detergents, soaking, dispersing and degreasing agents, since sufficient and uniform degreasing is necessary to manufacture high-quality articles. In practice the mildest possible nonionic surfactants have been used in minimum amounts, representing a compromise between the use of a surfactant required for degreasing and the resulting impairment of the wet blue material with respect to waterproofing.
Moreover, the increasing portion of wet blue material that is incorporated as intermediate product all over the world, has frequently made it necessary to carry out a so-called washing stage since the respective wet blue material, mainly for reasons of rapid through-put, has been degreased and prepared in an unsatisfactory manner. In addition, attention must be paid to the fact that different wet blues frequently are of a different quality and that there is the need to process the different wet blue materials into a uniform end product in one operation.
Another reason for quality reduction is the autoxidation of the natural fat remaining in the grain layer exposed to air, if stored for longer periods; and this is quite likely in case of wet blues (storage periods of up to one year are possible). Both events may result in the fact that the water repellent agent insufficiently penetrates the leather and therefore is not able to develop its action to the required degree.
Accordingly, it has been the object of the present invention to provide auxiliary agents and/or technologies to obtain an improved water repellent action by treating the wet blues or the hides and skins in the beamhouse. For this reason, these substances had to have a sufficient dispersing or emulsifying action. DE-OS 2 21 9 806 discloses the use of fatty acid amides as fatliquoring agents for materials having a fibrous structure. Fatliquoring of leather is carried out to impart a pleasant fatty handle to the material, and it has nothing to do with the waterproofing of leather. What is more, fatliquoring aims at producing soft leathers. Consequently, preferred compounds are the condensation products of the amino carboxylic acids sarcosine, .beta.-alanine, o-amino-benzenedicarboxylic acid, and .epsilon.-aminocaproic acid with fatty acids of natural origin. The claimed compounds are exclusively used to fatliquor retanned leathers. A lower water absorbency is noted with this application; it is exclusively carried out in fatliquoring.
EP 0 21 3 480 describes oleic acid sarcoside and other sarcosides used as emulsifiers for silicone oils, and a process for waterproofing leathers and furs with these silicone oil emulsions. It claims the use of salts of N(C.sub.9 -C.sub.20 -acyl)amino acids to emulsify silicone oil in aqueous phase in the water repellent treatment. This process is carried out during or after retannage.
Amides and anilides of higher fatty acids are described in literature as effective detergents, wetting, dispersing and leveling agents in the textile industry (DE 635 522), and they are used. Because of the pronounced hydrophilic properties they are avoided in waterproofing: Like almost all water repellents, all surfactants or strongly emulsified fatliquors impair the water repellent action in this case as well (BASF, technical notice to Densodrin S, issue May 1988).
Most surprisingly, it has been found that--despite their hydrophilic action--the use of these surface-active substances results in an improvement of the water repellent effect. The used surfactants may be ionic or nonionic. Suitable anionic surfactants in
REFERENCES:
patent: 2964425 (1960-12-01), Holzinger et al.
patent: 3322490 (1967-05-01), Gagliardi
patent: 4701269 (1987-10-01), Bay et al.
patent: 4740210 (1988-04-01), Amati
patent: 4968621 (1990-11-01), Pfleiderer et al.
patent: 4973427 (1990-11-01), Amati
patent: 5166337 (1992-11-01), Ripke
patent: 5286263 (1994-02-01), Schaffer
patent: 5501707 (1996-03-01), Schieferstein
patent: 5503754 (1996-04-01), Counts et al.
patent: 5525509 (1996-06-01), Christner et al.
patent: 5534035 (1996-07-01), Allen et al.
patent: 5658484 (1997-08-01), Lohmann
Ullmann's Encyclopedia of Industrial Chemistry, fifth edition, vol. A15, pp. 274-277, 1990.
Stather, Gerbereichemie Und Gerbereitechnologie (Tanning Chemistry and Tanning Technology), pp. 566 and 715, Akademie-Verlag, Berlin (1867) (month unknown).
Hayden, Tenside Als Hilfsmittel Zur Herstellung Wasservester Leder (Surfactants as Auxillary Agents in the Production of Water-Resistant Leather), Das Leder 20:4-8 (1969) (Month Unknown).
Pauckner, et al., "Neuere Untersuchungen ueber die Hydrophobierung von Leder" (New Investigations on the Hydrophobizing of Leather), Das Leder 28:97-107 (1977) (Month Unknown).
Kneip, "Polymere in der Fettung und Hydrophobierung von Leder" (Polymers in the Fat-Liquoring and Hydrophobization of Leather), Das Leder, No. 5, pp. 106, 108-109 (1995) (Month Unknown).
Diamond Alan
Stockhausen GmbH & Co. KG
LandOfFree
Process for treating leathers with surfactants to improve water does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for treating leathers with surfactants to improve water , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for treating leathers with surfactants to improve water will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-845654