US 12,071,573 B2
Pressure-sensitive adhesive sheet and method for peeling pressure-sensitive adhesive sheet
Naofumi Kosaka, Ibaraki (JP); Yosuke Shimizu, Ibaraki (JP); Satoshi Honda, Ibaraki (JP); Taiki Shimokuri, Ibaraki (JP); Shou Takarada, Ibaraki (JP); Masayuki Satake, Ibaraki (JP); Kenichi Okada, Ibaraki (JP); Atsushi Takashima, Ibaraki (JP); Ginji Mizuhara, Ibaraki (JP); Masayuki Okamoto, Ibaraki (JP); and Ryoko Asai, Ibaraki (JP)
Assigned to NITTO DENKO CORPORATION, Ibaraki (JP)
Appl. No. 16/967,504
Filed by Nitto Denko Corporation, Ibaraki (JP)
PCT Filed Jan. 28, 2019, PCT No. PCT/JP2019/002795
§ 371(c)(1), (2) Date Aug. 5, 2020,
PCT Pub. No. WO2019/151194, PCT Pub. Date Aug. 8, 2019.
Claims priority of application No. 2018-018621 (JP), filed on Feb. 5, 2018; application No. 2018-109385 (JP), filed on Jun. 7, 2018; and application No. 2018-143420 (JP), filed on Jul. 31, 2018.
Prior Publication US 2021/0214587 A1, Jul. 15, 2021
Int. Cl. C09J 7/38 (2018.01); B32B 7/06 (2019.01); B32B 27/18 (2006.01); B32B 27/30 (2006.01); B32B 37/12 (2006.01); B32B 37/18 (2006.01); B32B 38/10 (2006.01); C09J 11/06 (2006.01); C09J 11/08 (2006.01); C09J 133/08 (2006.01)
CPC C09J 7/385 (2018.01) [B32B 7/06 (2013.01); B32B 27/18 (2013.01); B32B 27/308 (2013.01); B32B 37/12 (2013.01); B32B 37/182 (2013.01); B32B 38/10 (2013.01); C09J 11/06 (2013.01); C09J 11/08 (2013.01); C09J 133/08 (2013.01); B32B 2037/1276 (2013.01); B32B 2307/728 (2013.01); B32B 2333/12 (2013.01); B32B 2405/00 (2013.01); C09J 2301/408 (2020.08); C09J 2301/502 (2020.08); C09J 2433/00 (2013.01); C09J 2467/006 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer,
wherein the pressure-sensitive adhesive layer comprises a layer A forming at least one surface of the pressure-sensitive adhesive layer;
wherein the layer A is a layer formed from a photocurable pressure-sensitive adhesive composition or a solvent-based pressure-sensitive adhesive composition;
wherein the layer A further comprises a hydrophilicity enhancer, wherein the hydrophilicity enhancer comprises a surfactant selected from the group consisting of anionic surfactants; cationic surfactants; and nonionic surfactants having an HLB value of at least 3 and no more than 18 or less; and
the pressure-sensitive adhesive sheet has:
an adhesive strength N0 of 2.0 N/10 mm or greater, after one day at room temperature following application of the layer A side to a surface of an alkaline glass plate as an adherend fabricated by a float method, the surface of the glass plate has a contact angle of 5° to 10° with distilled water;
a water-resistant adhesive strength reduction rate of 30% or lower, determined by a first formula (1−(N1/N0))×100 based on a water-resistant adhesive strength N1 (N/10 mm) and an adhesive strength N0 (N/10 mm), wherein N1 is measured after the layer A side is applied to a surface of an alkaline glass plate as an adherend fabricated by a float method with the surface of the alkaline glass plate having a contact angle of 5° to 10° with distilled water, and a resultant assembly is stored at room temperature for one day, immersed in water for 30 minutes, taken out from the water and then residual water is wiped off; and
a water-peel adhesive strength reduction rate of 75% or higher, determined by a second formula (1−(N2/N0))×100 based on a water-peel strength N2 (N/10 mm) and an adhesive strength N0 (N/10 mm), wherein N2 is measured according to JIS Z0237:2009 “10.4.1 Method 1: 180° Peel Strength to Test Plate” after the layer A side is applied to a surface of an alkaline glass plate as an adherend fabricated by a float method with the surface of the alkaline glass plate having a contact angle of 5° to 10° with distilled water, stored at room temperature for one day, 20 μL of distilled water is dropped onto the adherend and the distilled water is allowed to enter an interfacial edge between the pressure-sensitive adhesive layer and the adherend; in particular, measured using a tensile tester at a test temperature of 23° C. at a tensile speed of 300 mm/min at a peel angle of 180°, and
wherein the hydrophilicity enhancer is included in an amount of at least 0.01 part by weight up to 20 parts by weight relative to 100 parts by weight of monomers forming a polymer included in the layer A.