Pressure sensitive adhesive composition
The present applicant relates to a pressure-sensitive adhesive composition, and optical laminate, a polarizing plate, and a display device. In an embodiment of the present applicant, the pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive which has an excellent cohesive force or stress relaxation property, and thus has superior endurance reliability and light leakage suppression performance or the like may be provided. The pressure-sensitive adhesive composition according to an embodiment of the present applicant may be used, for example, for an optical film such as a polarizing plate or the like.
1. A pressure-sensitive adhesive laminate, comprising:
a film selected from the group consisting of an optical film and a polarizing film; and
a pressure-sensitive adhesive layer which is present on one side or both sides of the film, and includes a pressure-sensitive adhesive composition in which a crosslinked structure is formed, where the pressure-sensitive adhesive composition comprises:
a diblock copolymer having a first block having a glass transition temperature of 50° C. or more, wherein the first block comprises a polymerization unit derived from a methacrylic acid ester monomer; and a second block having a crosslinkable functional group and a glass transition temperature of −10° C. or less, wherein the second block comprises a polymerization unit derived from acrylic acid ester monomer and copolymerizable monomer having the crosslinkable functional group,
wherein the diblock copolymer has a number average molecular weight in a range of 200,000 to 374,000 and has a molecular weight distribution ranging from greater than 2.5 to 5.0.
2. The pressure-sensitive adhesive laminate of claim 1 , wherein the first block has a number average molecular weight in a range of 10,000 to 250,000.
3. The pressure-sensitive adhesive laminate of claim 1 , wherein the diblock copolymer has a room temperature viscosity of 3,000 cP or more in a state in which the diblock copolymer is diluted with ethyl acetate such that contents of solid fractions of the block copolymer are 30 wt %.
4. The pressure-sensitive adhesive laminate of claim 1 , wherein a crosslinkable functional group is not included in the first block, and only included in the second block.
5. The pressure-sensitive adhesive laminate of claim 1 , wherein the crosslinkable functional group is a hydroxy group.
6. The pressure-sensitive adhesive laminate of claim 1 , wherein the second block comprises a polymerization unit derived from 90 to 99.9 parts by weight of the acrylic acid ester monomer, and 0.1 to 10 parts by weight of the copolymerizable monomer having the crosslinkable functional group.
7. The pressure-sensitive adhesive laminate of claim 1 , further comprising a crosslinking agent which has two or more functional groups capable of reacting with the crosslinkable functional group.
8. The pressure-sensitive adhesive laminate of claim 7 , wherein the crosslinking agent is included at a range of 0.01 parts by weight to 10 parts by weight with respect to 100 parts by weight of the block copolymer.
9. A display device comprising the pressure-sensitive adhesive laminate of claim 1 , wherein the film is the optical film.
10. A display device comprising the pressure-sensitive adhesive plate of claim 1 , wherein the film is the polarizing film.