Leather production

Abstract

Application to leather of various leather treatment agents, in particular dyes, is improved by the use of materials such as substantially linear surfactants having amphoteric head groups.

1 . Use of a material of formula (I) in the production of leather:  
       R 1 —(R 2 —) n  (R 3 —) m  R 4    (I)  
       in which: 
 R 1  represents a substituted or unsubstituted group having a C8 to C18 backbone;  
 R 2  represents a NHCO group;  
 R 3  represents a substituted or unsubstituted group having a C2 to C8 backbone;  
 R 4  represents an amine oxide, sulphonate, phosphate or betaine group;  
 n is 0 or 1; and  
 m is 0 or 1.  
 
     
     
         2 . Use according to  claim 1 , in which n is 0 and m is 0.  
     
     
         3 . Use according to  claim 1  or 2, in which R 1  is unsubstituted or is saturated and substituted with four or fewer groups each of which has four or fewer carbon atoms.  
     
     
         4 . Use according to any of claims  1 ,  2  and  3 , in which R 1  is non-polar.  
     
     
         5 . Use according to any preceding claims, in which R 1  is an alkyl group.  
     
     
         6 . Use according to any preceding claim, in which R 4  is amphoteric.  
     
     
         7 . Use according to any preceding claim, in which R 4  is a group of formula (II):  
       
         
           
           
               
               
           
         
       
       in which each of R 5  and R 6 , which may be the same or different, is a straight or branched alkyl group having from 1 to 4 carbon atoms, and a is 0 or 1.  
     
     
         8 . Use according to any preceding claim, for the incorporation into and/or onto the leather of one or more leather treatment agents.  
     
     
         9 . Use according to  claim 8 , in which the leather treatment agent comprises: 
 a pre-tanning agent,    a tanning agent,    a retanning agent,    a lubricant,    a filling agent,    a softening agent,    a fatliquor,    a liming agent,    a de-liming agent,    a bating agent,    a dye, or    a dye fixing agent.    
     
     
         10 . Use according to  claim 9  for increasing the colour yield of a dye relative to the amount of dye applied to the leather and/or relative to the dying time.  
     
     
         11 . Use according to  claim 9  or  10 , in which the treatment agent comprises an acid dye, a direct dye, a solubilized sulphur dye and/or a reactive dye.  
     
     
         12 . Use according to any of  claims 8  to  11 , in which the material of formula (I) is applied to the leather prior to or simultaneously with the leather treatment agent.  
     
     
         13 . Use according to  claim 12 , in which material of formula (I) is applied to the leather prior to the leather treatment agent; at least part of said material is then removed from the leather; and then said agent is applied to the leather.  
     
     
         14 . Use according to any preceding claim, in which the material of formula (I) is applied to the leather by: 
 hand or machine padding,    roller coating,    curtain coating,    through feed roller application,    drumming,    spraying, or    dip coating.    
     
     
         15 . Use according to any preceding claim in which a UV absorber is applied to the leather before, simultaneously with, or after application to the leather of the material of formula (I).  
     
     
         16 . Use according to any preceding claim, in which the material of formula (I) serves to cause swelling of collagen of the leather by disrupting hydrogen bonds between collagen chains.  
     
     
         17 . Use according to any preceding claim, in which the material of formula (I) serves to increase the effective number of binding sites for leather treatment agents.  
     
     
         18 . A material of formula (I) as defined in any of  claims 1  to  7  for use in the production of leather.  
     
     
         19 . Use of a substantially linear surfactant having an amphoteric head group in the production of leather.  
     
     
         20 . Use according to  claim 19 , for the incorporation into and/or onto the leather of one or more leather treatment agents.  
     
     
         21 . Use according to  claim 20 , in which the leather treatment agent comprises: 
 a pre-tanning agent,    a tanning agent,    a retanning agent,    a lubricant,    a filling agent,    a softening agent,    a fatliquor,    a liming agent,    a de-liming agent,    a bating agent,    a dye, or    a dye fixing agent.    
     
     
         22 . Use according to any of claims  19 ,  20  or  21 , for increasing the colour yield of a dye relative to the amount of dye applied to the leather and/or relative to the dying time.  
     
     
         23 . Use according to any preceding claim, wherein the material of formula (I) or the surfactant as the case may be serves to cause swelling of collagen of the leather by disrupting hydrogen bonds between collagen chains and/or to increase the effective number of binding sites for leather treatment agents.  
     
     
         24 . A substantially linear surfactant having an amphoteric head group for use in the production of leather.  
     
     
         25 . A composition for use in the production of leather, which comprises: 
 (1) a material of formula (I) as defined in any of  claims 1  to  7  or a substantially linear surfactant having an amphoteric head group; and    (2) one or more leather treatment agents.    
     
     
         26 . A composition according to  claim 25 , in which the leather treatment agent comprises: 
 a pre-tanning agent,    a tanning agent,    a retanning agent,    a lubricant,    a filling agent,    a softening agent,    a fatliquor,    a liming agent,    a de-liming agent,    a bating agent,    a dye, or    a dye fixing agent.    
     
     
         27 . A composition according to  claim 26 , in which the agent comprises a dye.  
     
     
         28 . A composition according to  claim 27 , which comprises 0.1 to 10% by weight of component (1) and 0.1-30% by weight of any individual component (2).  
     
     
         29 . A composition according to any of  claims 25  to  28 , which additionally comprises: 
 (3) a UV-absorber.  
 
     
     
         30 . Leather produced by a method that involves the use according to any of  claims 1  to  17  and  19  to  23 .  
     
     
         31 . An article comprising leather according to  claim 30 .  
     
     
         32 . An article according to  claim 31 , being: 
 a ball,    an article of footwear,    a glove or mitt,    an article of clothing, or    leather goods.