Patent ID: 8735632

Claim:
A process for the preparation of polyglycerol based UV filters comprising the sequential steps of: (a) conducting ring-opening polymerization of x mol equivalents of glycidol using 1 mol equivalent of a polyol starter unit with y mol equivalents hydroxyl-groups, followed by (b) conducting block copolymerization with z X (x+y) mol equivalents of propyleneoxide to form a hyperbranched polyether-polyol backbone carrying (x+y) mol equivalents hydroxyl-groups, followed by (c) conducting partial or total etherification of the hydroxyl groups with 3-[1-(4-Hydroxymethyl-phenyl)-meth-(E)-ylidene]-1,7,7-trimethyl-bicyclo[2.2.1]heptan-2-one, wherein x is an integer from 3-16 and y is an integer from 2-6, and z is an integer from 0-10.