Polymeric retan fatliquor for low fogging upholstery leather

A method for imparting low fogging characteristics to leather which has been tanned and not previously subjected to a fatliquor comprising subjecting tanned leather to at least one weight percent copolymer solids, based on the weight of the leather of a dispersion of an amphiphilic copolymer, substantially free from organic solvent, formed from greater than 10 percent by weight to less than 50 percent by weight of at least one water-soluble ethylenically unsaturated acidic or basic hydrophilic comonomer selected from the group consisting of acrylic acid, methacrylic acid, itaconic add, fumaric acid, maleic acid, and anhydrides of such acids;

• acid substituted (meth)acrylates, acid substituted (meth)acrylamides and basic substituted (meth)acrylates and (meth)acrylamides and greater than 50 percent by weight to less than 90 weight percent of at least one hydrophobic comonomer selected from the group consisting of C.sub.4 to C.sub.12 alkyl acrylates, C.sub.4 to C.sub.12 alkyl methacrylates, C.sub.4 to C.sub.12 1-alkenes, and vinyl esters of C.sub.4 to C.sub.12 alkyl carboxylic acids, where said amphiphilic copolymer has a weight average molecular weight of from about 2500 to about 100,000 and where the leather so treated has a gravimetric fogging value not more than 2 mg greater than the gravimetric fogging value of the leather after tanning but before any subsequent treatment.