Adhesive tape

Abstract

To provide a pressure-sensitive adhesive tape capable of preventing an adhesive layer from lifting from a base material.SOLUTION: A pressure-sensitive adhesive tape includes a base material and an adhesive layer arranged at least on one side of the base material. The adhesive layer includes a thermal expansive microsphere and an adhesive agent. The thermal expansive microsphere includes a shell and a volatile substance contained inside the shell. A resin constituting the shell includes a constitutional unit having a carboxyl group. In one embodiment, a glass-transition temperature (Tg) of the resin constituting the shell is 120°C or higher.SELECTED DRAWING: Figure 1

Claims

1. The device comprises a base material, an adhesive layer disposed on at least one side of the base material, and an elastic layer disposed between the adhesive layer and the base material. The adhesive layer comprises thermally expandable microspheres and adhesive, The thermally expandable microsphere is composed of a shell and a volatile substance contained within the shell. The resin constituting the shell includes constituent units having carboxyl groups, In the resin constituting the shell, the content ratio of constituent units having carboxyl groups is 10 parts by weight or more per 100 parts by weight of the resin. The volatile substance is an organic solvent, and the difference between the boiling point (bp) of the organic solvent and the glass transition temperature (Tg) of the resin constituting the shell (Tg-bp) is between 50°C and 150°C. The adhesive comprises a base polymer having an OH group or a COOH group, The acid value of the base polymer is 0 to 100. The base material includes a resin sheet, The resin constituting the resin sheet is polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyamide, fully aromatic polyamide, polyimide, polyvinyl chloride, polyphenylene sulfide, fluororesin, or polyether ether ketone. Adhesive tape.

2. The adhesive tape according to claim 1, wherein the glass transition temperature (Tg) of the resin constituting the shell is 120°C or higher.

3. The adhesive tape according to claim 1 or 2, wherein the elastic modulus of the adhesive layer at 23°C, determined by nanoindentation, is 0.1 MPa to 500 MPa.

4. The adhesive tape according to any one of claims 1 to 3, wherein the adhesive is an acrylic adhesive.

5. The adhesive tape according to any one of claims 1 to 4, wherein the adhesive comprises an isocyanate-based crosslinking agent or an epoxy-based crosslinking agent.

6. The adhesive tape according to any one of claims 1 to 5, wherein the initial adhesive force a when the adhesive surface of the adhesive tape is attached to a polyethylene terephthalate film at an ambient temperature of 25°C is 1.5 N / 20 mm to 20 N / 20 mm.

7. The adhesive tape according to any one of claims 1 to 6, wherein the adhesive layer is provided on both sides of the base material.

8. The adhesive tape according to any one of claims 1 to 6, wherein the adhesive layer is provided on one side of the substrate and another adhesive layer is provided on the other side of the substrate.

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