CN-122029248-A - Pressure-sensitive adhesive sheet

Abstract

The invention provides an adhesive sheet which has a polyester adhesive layer that can contribute to reducing environmental load and is excellent in removability. An adhesive sheet according to one embodiment of the present invention includes a base material, and an adhesive layer disposed on at least one side of the base material, wherein the adhesive layer includes an active energy ray-curable adhesive that includes a polyester resin having an unsaturated group, a crosslinking agent, and a photopolymerization initiator, and the active energy ray-curable adhesive contains substantially no organic solvent.

Inventors

• Qu Neijiazhi
• Shibano Kamasashiya
• TOMIYAMA YASUSHI
• NAKAYAMA KOICHI
• Shi Jianzhiye
• FEI YONGJUN

Assignees

• 日东电工株式会社

Dates

Publication Date

20260512

Application Date

20241002

Priority Date

20231020

Claims (5)

1. 1. An adhesive sheet comprising a base material and an adhesive layer disposed on at least one side of the base material, The adhesive layer contains an active energy ray-curable adhesive, The active energy ray-curable adhesive comprises a polyester resin having an unsaturated group, a crosslinking agent, and a photopolymerization initiator, The active energy ray-curable adhesive contains substantially no organic solvent.
2. 2. The adhesive sheet according to claim 1, wherein the weight average molecular weight of the unsaturated group-containing polyester resin is 0.2X 10 4 ～2.0×10 4 .
3. 3. The adhesive sheet according to claim 1, wherein the unsaturated group-containing polyester resin is obtained by reacting a polyester resin with a compound having a polymerizable carbon-carbon double bond, The compound having a polymerizable carbon-carbon double bond has an isocyanate group.
4. 4. The adhesive sheet according to claim 3, wherein the compound having a polymerizable carbon-carbon double bond is at least 1 selected from the group consisting of 2-methacryloxyethyl isocyanate, 2-acryloxyethyl isocyanate, 2-isocyanatoethyl methacrylate, methacryloyl isocyanate and m-isopropenyl- α, α -dimethylbenzyl isocyanate.
5. 5. The adhesive sheet according to claim 1, wherein the crosslinking agent is an isocyanate-based crosslinking agent.

Description

Pressure-sensitive adhesive sheet Technical Field The present invention relates to an adhesive sheet. Background In the production process in various industrial fields including the electric and electronic fields, an adhesive sheet is widely used for the purpose of temporarily fixing a workpiece. As such an adhesive sheet, an easily releasable adhesive tape is known which exhibits an adhesive property at the time of temporary fixation and exhibits a releasability by a predetermined external stimulus without fixation (for example, patent document 1). On the other hand, the demand for reducing environmental load has been increasing year by year, and it is also demanded to reduce environmental load at the time of manufacturing, at the time of use, and the like for the pressure-sensitive adhesive sheet as described above. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2001-131507 Disclosure of Invention Problems to be solved by the invention The present invention has been made to solve the above-described conventional problems, and an object of the present invention is to provide an adhesive sheet having a polyester-based adhesive layer that contributes to reduction of environmental load and having excellent removability. Means for solving the problems [1] An adhesive sheet according to one embodiment of the present invention includes a base material, and an adhesive layer disposed on at least one side of the base material, wherein the adhesive layer includes an active energy ray-curable adhesive that includes a polyester resin having an unsaturated group, a crosslinking agent, and a photopolymerization initiator, and the active energy ray-curable adhesive contains substantially no organic solvent. [2] The pressure-sensitive adhesive sheet of item [1], wherein the weight average molecular weight of the unsaturated group-containing polyester resin is 0.2X10- 4～2.0×104. [3] The pressure-sensitive adhesive sheet according to [1] or [2], wherein the unsaturated group-containing polyester resin is obtained by reacting a polyester resin with a compound having a polymerizable carbon-carbon double bond, and the compound having a polymerizable carbon-carbon double bond may have an isocyanate group. [4] The pressure-sensitive adhesive sheet according to item [3], wherein the compound having a polymerizable carbon-carbon double bond is at least 1 selected from the group consisting of 2-methacryloxyethyl isocyanate, 2-acryloxyethyl isocyanate, 2-isocyanatoethyl methacrylate, methacryloyl isocyanate and m-isopropenyl- α, α -dimethylbenzyl isocyanate. [5] The pressure-sensitive adhesive sheet according to any one of [1] to [4], wherein the crosslinking agent may be an isocyanate-based crosslinking agent. Effects of the invention According to the present invention, an adhesive sheet having a polyester-based adhesive layer that contributes to reduction of environmental load and having excellent removability can be provided. Drawings FIG. 1 is a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention. Detailed Description A. Pressure-sensitive adhesive sheet Fig. 1 is a schematic cross-sectional view of an adhesive sheet according to an embodiment of the present invention. The pressure-sensitive adhesive sheet 100 of this embodiment includes a base material 10 and a pressure-sensitive adhesive layer 20 disposed on at least one side of the base material 10. The adhesive layer contains an active energy ray-curable adhesive. The active energy ray-curable adhesive comprises a polyester resin having an unsaturated group, a crosslinking agent, and a photopolymerization initiator. The active energy ray-curable adhesive contains substantially no organic solvent. By substantially not containing an organic solvent, an active energy ray-curable adhesive with little environmental load can be provided. The concept of "substantially free of organic solvent" (hereinafter, also referred to as "solvent-free type") may include cases where a small amount of organic solvent inevitably existing in the raw material or organic solvent unintentionally mixed during production is contained. However, the amount of the organic solvent that is unintentionally contained is preferably 3 parts by weight or less, more preferably 1 part by weight or less, still more preferably 0.5 parts by weight or less, and particularly preferably 0.1 part by weight or less per 100 parts by weight of the active energy ray-curable adhesive. Examples of the organic solvent include, but are not limited to, ethyl acetate, toluene, and acetylacetone. In the present invention, by using "polyester resin having an unsaturated group" as a resin in which a curable component is preliminarily introduced as a base polymer of the solvent-free active energy ray curable adhesive, an adhesive sheet which is advantageous from the viewpoint of environment and is excellent in removability can be p