Method for bleaching cotton

Abstract

A method for bleaching cotton substrates comprises the steps of: (a) immersing an unbleached cotton substrate in an aqueous hydrogen peroxide solution at pH 4.5-11 at 15.degree.-90.degree. C. to saturate the cotton substrate with hydrogen peroxide solution; (b) removing the thus-saturated cotton substrate from the aqueous hydrogen peroxide solution and removing from the substrate hydrogen peroxide solution in excess of 50-500% by weight pick-up; (c) transferring the resulting cotton substrate to a bath of an inert high boiling organic heating medium at a temperature between 100.degree. C. and the boiling or decomposition point of the organic heating medium 5 sec-20 min and (d) removing the cotton substrate from the organic heating medium and separating entrained organic heating medium therefrom. The organic heating medium preferably comprises one or more of: A. an aromatic polyester of the formula C.sub.6 H.sub.z' --(COOR.sub.1).sub.z, wherein z is 3, 4, 5, or 6; z' is 6-z and R.sub.1 is higher alkyl; B. a cycloaliphatic diester of the formula ##STR1## wherein R is substituted or unsubstituted straight or branched chain alkyl of 4-20 carbon atoms or polyoxyalkylene of the formula HO(C.sub.x H.sub.y O).sub.n C.sub.x H.sub.y --; C. a bisterephthalate ester of an alkylphenylpolyoxyethanol; D. a triglyceride fat or oil; E. a silicone oil; F. a halogenated hydrocarbon; G. a glycol or glycol ether or H. a hydrocarbon wax or oil.

Dependencies are inferred from the claim text.