Method for surface hardening substance by layering particularly transparent polymethacrylate.

Process for improving the surfaces of materials, where improved surface is based on at least one thermoplastic layer polymethacrylate obtained by: mixing of polymers polymerized from monomer mixtures a. and b., where a. contains: A) 20 to 100 wt% of methylmethacrylate, B) 0 to 80% by weight of a (meth) acrylate other than methyl methacrylate, of formula I wherein represents hydrogen or methyl and R2 represents a alkyl or linear cycloalkyl moiety or branched having 1 to 18 carbon atoms or represents phenyl or naphthyl, ~ C) 0 to 40% by weight of an additional unsaturated monomer different from aA) and aB) but copolymerizable with these, and where ( aA) to (BC) result together 100% by weight, and 100 parts by weight of this polymerized mixture are added 0-80 parts by weight of other polymers and conventional additives in amounts from 0 to 150% by weight; and b. contains: A) 20 to 99% by weight of a (meth) acrylate of formula I wherein R1 represents hydrogen or methyl and R2 represents an alkyl radical linear or cycloalkyl moiety or branched having 1 to 18 carbon atoms or represents phenyl or naphthyl, B) 1 to 80% by weight of one or more "reactive monomers" bA) different copolymerizable with (bA) where (bA) and (bB) result together 100% by weight and 100 parts by weight of this polymerized mixture are added 0-80 parts by weight of other polymers and conventional additives in amounts of 0 to 150 30 parts by weight; and the polymethacrylate layer applied to the material at temperatures which permit the production of a chemical bond polymethacrylate layer to the material.