Claims
- 1. A method of preparing pressure sensitive adhesive products having one or more release layer and poly acrylate-based pressure sensitive adhesive layer, which comprises co-extruding a release layer consisting of a polyolefinic elastomer having a shearing modulus of less than 2.0.times.10.sup.8 dyne/cm.sup.2 according to JIS K 7213 test and surface wettability expressed in terms of an equilibrium contact angle of more than 55.degree. with respect to a standard liquid having a surface tension of 50 dyne/cm and used in JIS K 6768 test under the conditions of 20.+-.1.degree. C. and 65.+-.5% RH and olefinic resin forming a reinforcing interlayer for increasing the adhesion between a backing substrate and said release layer such that said elastomer is coated to a thickness of at least 1 micron, said elastomer forming said release layer being bonded to said substrate through said reinforcing interlayer, and said elastomer forming said release layer is kept in contact with said pressure sensitive adhesive layer over a given area to form a composite or integral layer thereof.
- 2. The method as recited in claim 1, in which said resin forming said reinforcing interlayer is a low-density polyethylene or its derivative.
- 3. The method as recited in claim 2, in which said polyolefinic elastomer is extruded at a temperature of 180.degree. to 290.degree. C. prevailing at the outlet of die lips, and said resin forming said reinforcing interlayer extruded at a temperature of 260.degree. to 330.degree. C. prevailing at the outlet of die lips.
- 4. A method of preparing pressure sensitive adhesive products having one or more release layer and a poly acrylate-based pressure sensitive adhesive layer, which comprises co-extruding a release layer composed of a resin mixture of a polyolefinic elastomer having a shearing modulus of less than 2.0.times.10.sup.8 dyne/cm.sup.2 according to JIS K 7213 test and surface wettability expressed in terms of an equilibrium contact angle of more 55.degree. with respect to a standard liquid having a surface tension of 50 dyne/cm and used in JIS K 6768 test under the conditions of 20.+-.1.degree. C. and 65.+-.5% RH and a polyethylene added thereto and olefinic resin forming a reinforcing interlayer for increasing the adhesion between a backing substrate and said release layer such that said resin mixture is coated to a thickness of at least 1 micron, said resin mixture forming said release layer being bonded to said substrate through said resin forming said interlayer, and said release layer consisting of said resin mixture being in contact with said adhesive layer over a given area to form a composite or integral layer thereof.
- 5. The method is recited in claim 4, in which said resin forming said reinforcing interlayer is a low-density polyethylene or its derivative.
- 6. The method as recited in claim 5, in which said resin mixture is extruded at a temperature of 200.degree. to 290.degree. C. prevailing at the outlets of die lips, and said resin extruded at a temperature of 260.degree. to 330.degree. C. prevailing at the outlets of die lips.
Priority Claims (4)
Number |
Date |
Country |
Kind |
53-137350 |
Nov 1978 |
JPX |
|
53-152628 |
Dec 1978 |
JPX |
|
54-60336 |
May 1979 |
JPX |
|
54-61513 |
May 1979 |
JPX |
|
Parent Case Info
This is a division of application Ser. No. 090,605 filed Nov. 2, 1979 now Pat. No. 4,339,485.
US Referenced Citations (5)
Divisions (1)
|
Number |
Date |
Country |
Parent |
90605 |
Nov 1979 |
|