| abstract |
Pressure-sensitive adhesive tape has a backing comprising 88-92 % acrylic polymer containing: 35-45 % of a first alkyl acrylate monomer wherein the alkyl groups contain 4 to 12 carbon atoms, 30-40 % of a second alkyl acrylate monomer wherein the alkyl groups contain 4 to 12 carbon atoms, 6- 10 % a first monoethylenically unsaturated polar copolymerizable monomer, 1-2 % a second monoethylenically unsaturated polar copolymerizable monomer, 0.3-0.5 % photoinitiator, 1-2 % filler, 0.05-0.07 % crosslinker/chain extender, and 8-12 % hollow glass microspheres dispersed evenly in the polymer; and a pressure-sensitive adhesive layer on at least one side of the backing. A method for preparing the adhesive tape involves partially polymerizing an oligomer, forming a coating composition, coating the composition onto a first liner with a second liner contiguously covering the first liner, and polymerizing the composition on the liners between two banks of ultraviolet light while cooling to form a foam-like sheet useful as a tape backing. |