US 2002/0004130 A1 · Acrylic foam-like tape

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.

Claims40

Dependent claims

An acrylic foam-like pressure-sensitive adhesive tape comprising:

(a) a layer of an acrylic foam-like backing comprising
(i) from about 88% to about 92% of an acrylic polymer comprising:
from about 35% to about 45% of a first alkyl acrylate monomer having alkyl groups which contain from 4 to 12 carbon atoms,
from about 30% to about 40% of a second alkyl acrylate monomer having alkyl groups which contain from 4 to 12 carbon atoms,
from about 6% to about 10% of a first monoethylenically unsaturated polar copolymerizable monomer, and
from about 1% to about 2% of a second monoethylenically unsaturated polar copolymerizable monomer;
and
(ii) from about 8% to about 12% of hollow glass microspheres dispersed evenly in said polymer;
and
(b) at least one layer of a pressure-sensitive adhesive.

7 more elements

A process for making a pressure-sensitive adhesive tape having an acrylic foam-like backing, the process comprising the steps of:

(1) preparing an oligomer while excluding oxygen and partially polymerizing the oligomer composition wherein the oligomer comprises from about 45% to about 55% of a first alkyl acrylate monomer having alkyl groups which contain from 4 to 12 carbon atoms, from about 35% to about 45% of a second alkyl acrylate monomer having alkyl groups which contain from 4 to 12 carbon atoms, from about 3% to about 4% of a first monoethylenically substituted monomer, and from about 0.04% to about 0.06% of at least one photoinitiator;
(2) forming a coating composition comprising from about 75% to about 80% by weight of said oligomer and a mixture having a first polar copolymerizable monoethylenically substituted monomer and a second polar copolymerizable monoethylenically substituted monomer having a combined weight percentage of from about 6% to about 9%, from about 0.3% to about 0.5% of at least one photoinitiator, from about 1% to about 2% filler, from about 0.05% to about 0.07% of a crosslinker/chain extender, and from about 8% to about 12% hollow glass microspheres, wherein, said coating composition is formed under a vacuum in the absence of oxygen and has a viscosity between 500 and 20,000 cps;
(3) coating the composition onto a first liner and having a second liner contiguously cover the composition on the first liner thereby excluding air;
(4) polymerizing the composition between the liners forming an essentially uniform foam-like sheet having glass microspheres evenly distributed therethrough;
and
(5) coating at least one surface of the foam-like sheet with a pressure-sensitive adhesive.

3 more elements

A process of making a pressure-sensitive adhesive tape having an acrylic foam-like backing, the method comprising the steps of:

(a) making an acrylic foam-like backing comprising the steps of
(1) preparing an oligomer composition which has a viscosity of about 80 cps by mixing the composition, bubbling an inert gas through the composition, and running the composition through a glass tube while exposing the oligomer to ultraviolet radiation wherein the oligomer composition consists essentially of about 51% isooctylacrylate, about 45% 2-ethylhexyl acrylate, about 3.5% acrylic acid, and about 0.04% benzoin ethyl ether;
(2) mixing 80% oligomer composition with about 6% acrylic acid, about 1.5% acrylamide, about 0.3% benzoin ethyl ether, about 1.6% fumed silica, about 0.06% 1,4 butanediol diacrylate;
and about 10.5% borosilicate glass wherein the borosilicate glass is from about 40 to about 70 microns in a high speed mixer;
(3) excluding oxygen by bubbling an inert gas through the resultant mixture while pulling a vacuum sufficient to eliminate voids therethrough resulting a composition having a viscosity between 500 and 20,000 cps
(4) coating the composition at a rate of about 5 meters per minute onto a first liner having a second liner cover the composition on the first liner thereby excluding air;
and
(5) exposing the composition on each side through the liners to ultraviolet radiation to polymerize the composition between the liners forming an essentially uniform foam-like sheet having glass microspheres evenly distributed therethrough;
and
(6) coating at least one surface of the foam-like sheet with a pressure-sensitive adhesive.

7 more elements

Dependencies are inferred from the claim text.

Acrylic foam-like tape

Life of this patent

Acrylic foam-like tape

Life of this patent

Abstract

Claims40