Flame-retardant pressure-sensitive adhesive composition
AssigneeMinnesota Mining and Manufacturing Company
InventorsRaymond J. Petras, Gaylord L. Groff
Life of this patent
Estimating the term…
Abstract
A flame-retardant pressure-sensitive adhesive composition that is compatible with enameled magnet wire is provided by adding to a base adhesive material certain halogenated organic compounds, such as decabromodiphenyl oxide, which exhibit little halogen or other loss upon exposure to elevated temperature.
Claims15
A flame-retardant pressure-sensitive adhesive composition for use on electrically insulating tape that is compatable, as defined herein, with magnet wire insulation, said adhesive composition providing, when applied in a 5-mil-thickness on a polyester film backing, at least 20 ounces of adhesion to steel per inch width, and said adhesive composition comprising (1) a base pressure-sensitive adhesive material that exhibits no more than about 3 weight-percent halogen loss after weeks at 175.degree. C and (2) at least 2.5 weight-percent of halogenated organic material that (a) is halogenated with either chlorine or bromine atoms that together constitute at least 40 weight-percent of the organic material, (b) exhibits no more than about 1 weight-percent loss when heated to 200.degree. C in a thermogravimetric analysis performed by raising the temperature of the organic material from room temperature at a rate of 40.degree. C/minute, (c) exhibits no more than about 3 weight-percent halogen loss after two weeks at 175.degree. C, (d) exhibits less than 10 percent loss in overall weight after two weeks at 175.degree. C and (e) comprises less than about 50 weight-percent of said adhesive composition.
A flame-retardant electrically insulating pressure-sensitive adhesive tape which is compatible, as defined herein, with magnet wire insulation and exhibits at least 20 ounces of adhesion to steel per inch width, comprising a flexible backing and at least one layer of pressure-sensitive adhesive composition united to the backing, said adhesive composition comprising (1) a base pressure-sensitive adhesive material that exhibits less than about 3 weight-percent halogen loss after two weeks at 175.degree. C, (2) at least 2.5 weight-percent of halogenated polynuclear aromatic ether that (a) is halogenated with either chlorine or bromine atoms that together constitute at least 40 weight-percent of said ether, (b) exhibits less than 1 weight-percent loss when heated to 200.degree. C in a thermogravimetric analysis performed by raising the temperature of said ether from room temperature at a rate of 40.degree. C/minute, (c) exhibits less than about 3 weight-percent halogen loss after two weeks at 175.degree. C, (b) exhibits less than 10 percent loss in overall weight after two weeks at 175.degree. C, and (e) comprises less than about 50 weight-percent of said adhesive composition, and (3) antimony trioxide.
A flame-retardant electrically insulating pressure-sensitive adhesive tape which is compatible, as defined herein, with magnet wire insulation and exhibits at least 20 ounces of adhesion to steel per inch of width comprising a flexible backing and at least one layer of pressure-sensitive adhesive composition united to the backing, said adhesive composition comprising an acrylate-based pressure-sensitive adhesive and 10 to 50 weight-percent of decabromodiphenyl oxide.
Dependencies are inferred from the claim text.