Pressure-sensitive adhesive sheet
A pressure-sensitive adhesive sheet has a substrate and a pressure-sensitive adhesive layer laminated on at least one side of the substrate. The sheet is configured such that: pressure-sensitive adhesive force N1, occurring after the pressure-sensitive adhesive layer is attached to a stainless steel plate (430 BA plate) and is left at 23° C. for 10 seconds, is 1.0 [N/20 mm] or less; pressure-sensitive adhesive force N2, occurring after the pressure-sensitive adhesive layer is attached and is aged at 80° C. for 5 minutes, is 3.0 [N/20 mm] or more; and N2/N1 is 5.0 or more.
1. A pressure-sensitive adhesive sheet comprising:
a substrate; and
a pressure-sensitive adhesive layer laminated on at least one side of the substrate,
the pressure-sensitive adhesive sheet being configured such that: pressure-sensitive adhesive force N1, occurring after the pressure-sensitive adhesive layer is attached to a stainless steel plate (430 BA plate) and is left at 23° C. for 10 seconds, is 1.0 [N/20 mm] or less; pressure-sensitive adhesive force N2, occurring after the pressure-sensitive adhesive layer is attached and is aged at 80° C. for 5 minutes, is 3.0 [N/20 mm] or more; and N2/N1 is 5.0 or more, wherein
the pressure-sensitive adhesive layer includes:
100 parts by mass of a polymer (A) having a glass transition temperature lower than 0° C.; and
0.1 to 20 parts by mass of a polymer (B) that contains, as monomer units, one of monomers (B1) having a functional group equivalent of 1000 g/mol or more but less than 15000 g/mol and having a polyorganosiloxane backbone and one of monomers (B2) producing a glass transition temperature of 40° C. or higher, and that has a weight average molecular weight of 10000 or more but less than 100000 (B),
the content of the monomer (B1) is 5% by mass or more but 50% by mass or less based on the mass of the total monomer components of the polymer (B),
the content of the monomer (B2) producing a glass transition temperature of 40° C. or higher is 10% by mass to 80% by mass based on the mass of the total monomer components of the polymer (B),
said one of monomers (B2) is a (meth)acrylic acid alkyl ester, and
a total thickness of the pressure-sensitive adhesive sheet is 3 μm or more but 500 μm or less.
2. The pressure-sensitive adhesive sheet according to claim 1 , wherein storage modulus at 23° C. of the pressure-sensitive adhesive layer, which is measured under a condition of shear strain at a frequency of 1 Hz by dynamic viscoelasticity measurement, is 1×10 6 Pa or less.
3. The pressure-sensitive adhesive sheet according to claim 1 , wherein a thickness of the substrate is 1 μm or more but 100 μm or less.
4. The pressure-sensitive adhesive sheet according to claim 1 , wherein the polymer (A) is an acrylic polymer.
5. The pressure-sensitive adhesive sheet according to claim 1 , wherein the monomer having a polyorganosiloxane backbone is one or more monomers selected from the group consisting of monomers represented by the following general formula (1) or (2):
[In Chemical Formulae (1) and (2), R 3 is hydrogen or methyl, R 4 is methyl or a monovalent organic group, and m and n are integers of 0 or more.]
6. The pressure-sensitive adhesive sheet according to claim 1 , wherein the functional group equivalent of monomer (B1) is 1000 g/mol or more but 4600 g/mol or less.
7. A pressure-sensitive adhesive sheet comprising:
a substrate; and
a pressure-sensitive adhesive layer laminated on at least one side of the substrate,
the pressure-sensitive adhesive sheet being configured such that: pressure-sensitive adhesive force N1, occurring after the pressure-sensitive adhesive layer is attached to a stainless steel plate (430 BA plate) and is left at 23° C. for 10 seconds, is 1.0 [N/20 mm] or less; pressure-sensitive adhesive force N2, occurring after the pressure-sensitive adhesive layer is attached and is aged at 80° C. for 5 minutes, is 3.0 [N/20 mm] or more; and N2/N1 is 5.0 or more, wherein
the pressure-sensitive adhesive layer includes:
100 parts by mass of a polymer (A) having a glass transition temperature lower than 0° C.; and
0.1 to 20 parts by mass of a polymer (B) that contains, as monomer units, one of monomers (B1) having a functional group equivalent of 1000 g/mol or more but less than 15000 g/mol and having a polyorganosiloxane backbone and one of monomers (B2) producing a glass transition temperature of 40° C. or higher, and that has a weight average molecular weight of 10000 or more but less than 100000 (B),
the polymer (B) does not include fluorine-containing monomer units,
the content of the monomer (B1) is 5% by mass or more but 50% by mass or less based on the mass of the total monomer components of the polymer (B),
the content of the monomer (B2) producing a glass transition temperature of 40° C. or higher is 10% by mass to 80% by mass based on the mass of the total monomer components of the polymer (B),
said one of monomers (B2) is a (meth)acrylic acid alkyl ester, and
a total thickness of the pressure-sensitive adhesive sheet is 3 μm or more but 500 μm or less.
8. The pressure-sensitive adhesive sheet according to claim 7 , wherein storage modulus at 23° C. of the pressure-sensitive adhesive layer, which is measured under a condition of shear strain at a frequency of 1 Hz by dynamic viscoelasticity measurement, is 1×10 6 Pa or less.
9. The pressure-sensitive adhesive sheet according to claim 7 , wherein a thickness of the substrate is 1 μm or more but 100 μm or less.
10. The pressure-sensitive adhesive sheet according to claim 7 , wherein the polymer (A) is an acrylic polymer.
11. The pressure-sensitive adhesive sheet according to claim 7 , wherein the monomer having a polyorganosiloxane backbone is one or more monomers selected from the group consisting of monomers represented by the following general formula (1) or (2):
[In Chemical Formulae (1) and (2), R 3 is hydrogen or methyl, R 4 is methyl or a monovalent organic group, and m and n are integers of 0 or more.]
12. The pressure-sensitive adhesive sheet according to claim 7 , wherein the functional group equivalent of monomer (B1) is 1000 g/mol or more but 4600 g/mol or less.