Surface protection film, and method for manufacturing organic light-emitting electronic device

1. A surface protective film comprising:

a base layer; and

an adhesive layer provided on one surface of the base layer,

wherein the adhesive layer comprises a cured product of an adhesive composition, comprising: a urethane polymer; an acrylic polymer; and a curing agent,

wherein the acrylic polymer comprises a monomer unit derived from an alkyl(meth)acrylate monomer having 10 or more carbon atoms, and

wherein an adhesive strength maintenance ratio of the adhesive layer, calculated by Equation 1, is 50% or more:

Adhesive strength maintenance ratio=(a high temperature peel strength)/(a low temperature peel strength)×100,  Equation 1

wherein the low temperature peel strength is a peel strength when the adhesive layer of the surface protective film is attached to glass and stored at 25° C. for 24 hours, and then the surface protective film is peeled off from the glass at a peel speed of 1.8 m/min, a peel angle of 180°, and a temperature of 25° C., and

wherein the high temperature peel strength is a peel strength when the adhesive layer of the surface protective film is attached to glass, stored at 25° C. for 24 hours, and then left to stand at 40° C. for 1 minute, and the surface protective film is peeled off from the glass at a peel speed of 1.8 m/min, a peel angle of 180°, and a temperature of 40° C.

2. The surface protective film of claim 1 , wherein the low temperature peel strength is 0.5 gf/in or more and 10 gf/in or less.

3. The surface protective film of claim 1 , wherein the high temperature peel strength is 0.5 gf/in or more and 5 gf/in or less.

4. The surface protective film of claim 1 , wherein, in the adhesive composition, the acrylic polymer is comprised in an amount of 1 part by weight to 20 parts by weight based on 100 parts by weight of the urethane polymer.

5. The surface protective film of claim 1 , wherein the monomer unit derived from the alkyl(meth)acrylate monomer having 10 or more carbon atoms is comprised in an amount of 1 wt % to 20 wt % based on a total amount of the monomer units comprised in the acrylic polymer.

6. The surface protective film of claim 1 , wherein the acrylic polymer comprises a monomer unit derived from a (meth)acrylate monomer comprising a hydroxyl group.

7. The surface protective film of claim 6 , wherein the monomer unit derived from the (meth)acrylate monomer comprising the hydroxyl group is comprised in an amount of 1 wt % to 20 wt % based on a total amount of the monomer units comprised in the acrylic polymer.

8. The surface protective film of claim 1 , wherein the acrylic polymer has a hydroxyl group value of 5 mgKOH/g to 40 mgKOH/g.

9. The surface protective film of claim 1 , wherein the base layer comprises a base film; and a first anti-static layer and a second anti-static layer respectively provided on both surfaces of the base film, and

wherein the adhesive layer is provided on a surface of the second anti-static layer, which is opposite to a surface on which the base film is provided.

10. The surface protective film of claim 1 , further comprising a protective layer provided on a surface of the adhesive layer, which is opposite to a surface on which the base layer is provided,

wherein the protective layer comprises: a protective film; and a third anti-static layer and a fourth anti-static layer respectively provided on both surfaces of the protective film, and

wherein the adhesive layer is provided on a surface of the third anti-static layer, which is opposite to a surface on which the protective film is provided.

11. A method for manufacturing an organic light emitting electronic device, the method comprising:

attaching an adhesive layer of the surface protective film of claim 1 onto an encapsulation layer of an organic light emitting element.

12. The method of claim 11 , wherein the organic light emitting element sequentially comprises a back plate, a plastic substrate, a thin film transistor, an organic light emitting diode, and an encapsulation layer.

13. The method of claim 11 , further comprising: peeling off the surface protective film from the encapsulation layer; and stacking a touch screen panel and a cover window on the encapsulation layer.