Patent ID: 8623978

Claim:
A process for the preparation of low-peroxide, water-insolubly crosslinked vinyllactam polymer by free-radical proliferous polymerization, comprising carrying out the polymerization in the presence of at least one organic substance acting as antioxidant and a crosslinker, wherein the crosslinker is produced in a step prior to the polymerization or is added to the polymerization, and wherein the at least one organic substance is selected from the group consisting of one or more tocopherols, catechin hydrate, uric acid, propyl 3,4,5-trihydroxybenzoate, 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl, tris(tetramethylhydroxypiperidinol) citrate, N-acetylcysteine, bis(2,2,6,6-tetramethylpiperidin-1-oxyl-4-yl)decanedioate and 1,2-diothiolane-3-pentanoic acid.