JPWO2020149117A1 - Surface protective film - Google Patents

Abstract

It does not easily peel off from the adherend, and even when stored for a long period of time in a harsh environment, it can sufficiently suppress heavy peeling over time, and the surface of the adherend can be attached to the adherend. Provided is a surface protective film having sufficiently low stain resistance. The surface protective film of the present invention is a surface protective film having an adhesive layer, and the adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 23 ° C. for 30 minutes, and then at a temperature of 23 ° C. When the peeling force A is the peeling force A when the surface protective film is peeled from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm / min, the peeling force A is 0.005N / 25mm to 0.50N / 25mm. The adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 100 ° C. for 2 days, and then the surface protective film is peeled from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm at a temperature of 23 ° C. When the peeling force when peeled at / minute is the peeling force B, the peeling force with time increase rate P1 calculated by (peeling force B / peeling force A) × 100 is 200% or less.

Description

The present invention relates to a surface protective film.

In the manufacturing process of an optical member or an electronic member, in order to prevent the surface of the optical member or the electronic member from being damaged during processing, assembly, inspection, transportation, etc., the optical member or the electron is generally used. A surface protective film is attached to the exposed surface of the member. Such a surface protective film is peeled off from an optical member or an electronic member when the need for surface protection is eliminated (Patent Document 1).

In an optical member or an electronic member to which such a surface protective film is attached, when the surface protective film is to be peeled off as described above, the surface protective film is at the interface between the optical member or the electronic member. It is important that only smooth peeling is possible.

However, when the optical member or the electronic member is provided with a fragile member such as a thin glass or a barrier film, when the attached surface protective film is to be peeled off, the conventional surface protective film having light peelability is released. Even when used, the fragile member may be damaged by the peeling force.

Therefore, a surface protective film having a lighter peeling property, that is, an ultra-light peeling property, has been reported as compared with a conventional surface protective film having a light peeling property (Patent Document 2).

However, the conventional technique has a problem that, for example, when it is stored for a long period of time in a harsh environment, its adhesive strength increases with time and it becomes heavy peeling.

In order to suppress the double peeling, there is also a method of adding an additive in an excessive amount as reported in Patent Document 2. However, when such a method is adopted, the degree of contamination on the surface of the adherend is large after the surface protection film is peeled off, and when the surface protection film is to be attached again, the surface protection film is contaminated due to the contamination on the surface of the adherend. There is a problem that it becomes difficult to stick.

As described above, for example, in the manufacturing process of optical members and electronic members, especially in the surface protective film attached to the exposed surface in order to prevent the surface from being scratched during processing, assembly, inspection, transportation, etc. It is required that heavy exfoliation over time can be sufficiently suppressed even when stored for a long period of time in a harsh environment, and that the contamination of the surface of the adherend can be sufficiently reduced.

Japanese Unexamined Patent Publication No. 2016-17109 Japanese Unexamined Patent Publication No. 2017-160422

The subject of the present invention is that it does not easily peel off from the adherend, can sufficiently suppress heavy peeling over time even when stored for a long period of time in a harsh environment, and is attached to the adherend. It is an object of the present invention to provide a surface protective film having a sufficiently low contamination property on the surface of the adherend.

The surface protective film of the present invention is
A surface protective film having an adhesive layer,
After the pressure-sensitive adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 23 ° C. for 30 minutes, the surface protective film is peeled off from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm / min at a temperature of 23 ° C. When the peeling force at the time of peeling is the peeling force A, the peeling force A is 0.005N / 25mm to 0.50N / 25mm.
The pressure-sensitive adhesive layer of the surface protective film was attached to a glass plate and left at a temperature of 100 ° C. for 2 days, and then the surface protective film was peeled from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm / min at a temperature of 23 ° C. When the peeling force at the time of peeling is the peeling force B, the peeling force with time increase rate P1 calculated by (peeling force B / peeling force A) × 100 is 200% or less.

In one embodiment, the storage elastic modulus of the pressure-sensitive adhesive layer at 23 ° C. is defined as the storage elastic modulus X1, and the storage elastic modulus at a temperature of 23 ° C. after the surface protective film is left at a temperature of 80 ° C. for 7 days is the storage elastic modulus. When the rate is Y1, the storage elastic modulus change rate Q1 calculated by (storage elastic modulus Y1 / storage elastic modulus X1) × 100 is 150% or less.

In one embodiment, the pressure-sensitive adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 23 ° C. for 7 days, and then the surface protective film is peeled off from the glass plate at a temperature of 23 ° C. by 180 degrees. When the peeling force when peeled at a peeling speed of 300 mm / min is the peeling force C, the peeling force with time increase rate P2 calculated by (peeling force C / peeling force A) × 100 is 160% or less.

In one embodiment, the surface protective film of the present invention has a residual adhesion rate of 50% or more on a glass plate at 23 ° C.

In one embodiment, the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition contains a heat-resistant stabilizer.

In one embodiment, the pressure-sensitive adhesive composition comprises a base polymer, a low molecular weight polyol, a silicone-based additive and / or a fluorine-based additive.

In one embodiment, the silicone-based additive is at least one selected from a siloxane bond-containing compound, a hydroxyl group-containing silicone-based compound, and a crosslinkable functional group-containing silicone-based compound.

In one embodiment, the fluorine-based additive is at least one selected from a fluorine-containing compound, a hydroxyl group-containing fluorine-based compound, and a crosslinkable functional group-containing fluorine-based compound.

In one embodiment, the base polymer is at least one selected from urethane prepolymers, polyols, acrylic resins, rubber resins, and silicone resins.

The optical member of the present invention is the one to which the surface protective film of the present invention is attached.

The electronic member of the present invention is the one to which the surface protective film of the present invention is attached.

According to the present invention, it does not easily peel off from the adherend, and even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be sufficiently suppressed, and the sticking to the adherend can be achieved. It is possible to provide a surface protective film having a sufficiently low contamination property on the surface of the adherend by attaching.

It is the schematic sectional drawing of the surface protection film by one Embodiment of this invention.

≪≪A. Surface protection film ≫≫
The surface protective film of the present invention has an adhesive layer. The surface protective film of the present invention may be provided with any suitable other member as long as it has the pressure-sensitive adhesive layer, as long as the effect of the present invention is not impaired. Typically, the surface protective film of the present invention has a base material layer and an adhesive layer.

FIG. 1 is a schematic cross-sectional view of a surface protective film according to an embodiment of the present invention. In FIG. 1, the surface protective film 10 includes a base material layer 1 and an adhesive layer 2. In FIG. 1, the base material layer 1 and the pressure-sensitive adhesive layer 2 are directly laminated.

In FIG. 1, the surface of the pressure-sensitive adhesive layer 2 on the opposite side of the base material layer 1 is provided with an arbitrary suitable release liner (sometimes referred to as a release sheet or separator) for protection until use or the like. It may be (not shown). As the release liner, for example, the surface of the base material (liner base material) such as paper or plastic film is treated with silicone, and the surface of the base material (liner base material) such as paper or plastic film is made of polyolefin resin. Examples include a laminated release liner. Examples of the plastic film as the liner base material include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, and polybutylene terephthalate film. Examples thereof include a polyurethane film and an ethylene-vinyl acetate copolymer film. The plastic film as the liner base material is preferably a polyethylene film.

The thickness of the release liner is preferably 1 μm to 500 μm, more preferably 3 μm to 450 μm, still more preferably 5 μm to 400 μm, and particularly preferably 10 μm to 300 μm.

The thickness of the surface protective film is preferably 5 μm to 500 μm, more preferably 10 μm to 450 μm, still more preferably 15 μm to 400 μm, and particularly preferably 20 μm to 300 μm.

In the surface protective film of the present invention, the pressure-sensitive adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 23 ° C. for 30 minutes, and then the surface protective film is peeled off from the glass plate at a temperature of 23 ° C. at an angle of 180 degrees. When the peeling force A is the peeling force A when peeling at a peeling speed of 300 mm / min, the peeling force A is preferably 0.005N / 25mm to 0.50N / 25mm, more preferably 0.007N / 25mm. It is ~ 0.40N / 25mm, more preferably 0.010N / 25mm to 0.30N / 25mm, still more preferably 0.012N / 25mm to 0.20N / 25mm, still more preferably 0.015N /. It is 25 mm to 0.10 N / 25 mm, particularly preferably 0.012 N / 25 mm to 0.050 N / 25 mm, and most preferably 0.010 N / 25 mm to 0.040 N / 25 mm. If the peeling force A is within the above range, the surface protective film of the present invention may not easily peel off from the adherend, and typically, during the manufacturing process of the optical member or the electronic member, the optical member or the surface protective film may be difficult to peel off. The surface protective film of the present invention attached to the exposed surface of the electronic member may be less likely to be peeled off. The details of the measurement of the peeling force A will be described later.

In the surface protective film of the present invention, the pressure-sensitive adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 100 ° C. for 2 days, and then the surface protective film is peeled off from the glass plate at a temperature of 23 ° C. at an angle of 180 degrees. When the peeling force B is the peeling force B when peeling at a peeling speed of 300 mm / min, the peeling force B is preferably 0.010N / 25mm to 1.0N / 25mm, and more preferably 0.010N / 25mm. It is ~ 0.50N / 25mm, more preferably 0.010N / 25mm to 0.20N / 25mm, particularly preferably 0.010N / 25mm to 0.10N / 25mm, and most preferably 0.010N / It is 25 mm to 0.070 N / 25 mm. When the peeling force B is within the above range, the surface protective film of the present invention can more sufficiently suppress heavy peeling over time even when stored for a long period of time in a harsh environment. The details of the measurement of the peeling force B will be described later.

In the surface protective film of the present invention, with respect to the peeling force A and the peeling force B, the peeling force with time increase rate P1 calculated by (peeling force B / peeling force A) × 100 is preferably 200% or less, more preferably. Is 190% or less, more preferably 180% or less, particularly preferably 170% or less, and most preferably 160% or less. As for the lower limit of the peeling force increase rate P1 with time, the smaller it is, the more preferable it is, but in reality, it is preferably 80% or more. If the peeling force increase rate P1 over time is within the above range, the surface protective film of the present invention does not easily peel off from the adherend, and even when stored for a long period of time in a harsh environment, the surface protective film is heavy over time. Detachment can be sufficiently suppressed.

In the surface protective film of the present invention, the pressure-sensitive adhesive layer of the surface protective film is attached to a glass plate and left at 23 ° C. for 7 days, and then the surface protective film is peeled off from the glass plate at a peeling angle of 180 degrees at a temperature of 23 ° C. When the peeling force C when peeling at a speed of 300 mm / min is taken as the peeling force C, the peeling force C is preferably 0.001N / 25mm to 0.50N / 25mm, and more preferably 0.001N / 25mm to. It is 0.30N / 25mm, more preferably 0.001N / 25mm to 0.20N / 25mm, still more preferably 0.003N / 25mm to 0.10N / 25mm, still more preferably 0.005N / 25mm. It is ~ 0.075N / 25mm, particularly preferably 0.008N / 25mm to 0.050N / 25mm, and most preferably 0.010N / 25mm to 0.040N / 25mm. When the peeling force C is within the above range, the surface protective film of the present invention can more sufficiently suppress heavy peeling over time even when stored for a long period of time in a harsh environment. The details of the measurement of the peeling force C will be described later.

In the surface protective film of the present invention, with respect to the peeling force A and the peeling force C, the peeling force with time increase rate P2 calculated by (peeling force C / peeling force A) × 100 is preferably 160% or less, more preferably. Is 155% or less, more preferably 150% or less, particularly preferably 145% or less, and most preferably 140% or less. As for the lower limit of the peeling force increase rate P2 with time, the smaller it is, the more preferable it is, but in reality, it is preferably 80% or more. If the rate of increase in peeling force over time P2 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and even when stored for a long period of time in a harsh environment, the surface protective film over time Heavy exfoliation can be suppressed more sufficiently.

In the surface protective film of the present invention, the storage elastic modulus X1 of the pressure-sensitive adhesive layer at 23 ° C. is preferably 1.0 × 10 ⁵ Pa to 1.0 × 10 ⁷ Pa, and more preferably 3.0 × 10. ^{It is 5} Pa to 7.0 × 10 ⁶ Pa, more preferably 5.0 × 10 ⁵ Pa to 5.0 × 10 ⁶ Pa, and particularly preferably 6.0 × 10 ⁵ Pa to 4.0 × 10. ^{It is 6} Pa, and most preferably 7.0 × 10 ⁵ Pa to 3.0 × 10 ^{6 Pa.} When the storage elastic modulus X1 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, the time passes. It is possible to more sufficiently suppress the heavy peeling in, and to further exhibit the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low. The details of the measurement of the storage elastic modulus X1 will be described later.

In the surface protective film of the present invention, the storage elastic modulus Y1 at a temperature of 23 ° C. after the surface protective film is left at a temperature of 80 ° C. for 7 days is preferably 1.0 × 10 ⁵ Pa to ^{1.0 × 10 7.} It is Pa, more preferably 2.0 × 10 ⁵ Pa to 7.0 × 10 ⁶ Pa, still more preferably 3.0 × 10 ⁵ Pa to 5.0 × 10 ⁶ Pa, and particularly preferably 5 It is 0.0 × 10 ⁵ Pa to 3.0 × 10 ⁶ Pa, and most preferably 6.0 × 10 ⁵ Pa to 2.0 × 10 ^{6 Pa.} When the storage elastic modulus Y1 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, the time passes. It is possible to more sufficiently suppress the heavy peeling in, and to further exhibit the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low. The details of the measurement of the storage elastic modulus Y1 will be described later.

In the surface protective film of the present invention, the storage elastic modulus change rate Q1 calculated by (storage elastic modulus Y1 / storage elastic modulus X1) × 100 is preferably 150% or less with respect to the storage elastic modulus X1 and the storage elastic modulus Y1. It is more preferably 145% or less, further preferably 140% or less, particularly preferably 135% or less, and most preferably 130% or less. As for the lower limit of the storage elastic modulus change rate Q1, the smaller it is, the more preferable it is, but in reality, it is preferably 80% or more. When the storage elastic modulus change rate Q1 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend is large. However, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

In the surface protective film of the present invention, the storage elastic modulus X2 of the pressure-sensitive adhesive layer at 100 ° C. is preferably 1.0 × 10 ⁵ Pa to 7.0 × 10 ⁶ Pa, and more preferably 3.0 × 10. ^{It is 5} Pa to 5.0 × 10 ⁶ Pa, more preferably 5.0 × 10 ⁵ Pa to 3.0 × 10 ⁶ Pa, and particularly preferably 6.0 × 10 ⁵ Pa to 2.0 × 10. ^{It is 6} Pa, and most preferably 6.5 × 10 ⁵ Pa to 1.5 × 10 ^{6 Pa.} When the storage elastic modulus X2 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, the time passes. It is possible to more sufficiently suppress the heavy peeling in, and to further exhibit the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low. The details of the measurement of the storage elastic modulus X2 will be described later.

In the surface protective film of the present invention, the storage elastic modulus Y2 at a temperature of 100 ° C. after the surface protective film is left at a temperature of 80 ° C. for 7 days is preferably 1.0 × 10 ⁵ Pa to ^{1.0 × 10 7.} It is Pa, more preferably 2.0 × 10 ⁵ Pa to 7.0 × 10 ⁶ Pa, still more preferably 3.0 × 10 ⁵ Pa to 5.0 × 10 ⁶ Pa, and particularly preferably 5 It is 0.0 × 10 ⁵ Pa to 2.0 × 10 ⁶ Pa, and most preferably 5.5 × 10 ⁵ Pa to 1.0 × 10 ^{6 Pa.} When the storage elastic modulus Y2 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, the time passes. It is possible to more sufficiently suppress the heavy peeling in, and to further exhibit the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low. The details of the measurement of the storage elastic modulus Y2 will be described later.

In the surface protective film of the present invention, the storage elastic modulus change rate Q2 calculated by (storage elastic modulus Y2 / storage elastic modulus X2) × 100 is preferably 150% or less with respect to the storage elastic modulus X2 and the storage elastic modulus Y2. It is more preferably 145% or less, further preferably 140% or less, particularly preferably 135% or less, and most preferably 130% or less. As for the lower limit of the storage elastic modulus change rate Q2, the smaller it is, the more preferable it is, but in reality, it is preferably 80% or more. When the storage elastic modulus change rate Q2 is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend is large. However, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

The surface protective film of the present invention has a residual adhesion rate of preferably 50% or more, more preferably 60% to 100%, still more preferably 70% to 100%, and particularly preferably 80% to 100%. %, Most preferably 85% to 100%. When the residual adhesion rate is within the above range, the surface protective film of the present invention can exhibit the effect that the contamination of the surface of the adherend by being attached to the adherend is sufficiently low. The details of the measurement of the residual adhesion rate will be described later.

The surface protective film of the present invention can be produced by any suitable method. As such a manufacturing method, for example,
(1) A method of applying a solution of a material for forming an adhesive layer or a thermal melt solution onto a base material layer,
(2) A method of transferring a pressure-sensitive adhesive layer formed by applying a solution of a material for forming a pressure-sensitive adhesive layer or a heat-melting liquid on a separator onto a base material layer.
(3) A method of extruding a material for forming an adhesive layer onto a base material layer to form and apply the adhesive layer.
(4) A method of extruding a base material layer and an adhesive layer in two or multiple layers,
(5) A method of laminating a single layer of an adhesive layer on a base material layer or a method of laminating two layers of an adhesive layer together with a laminating layer.
(6) A method of laminating a pressure-sensitive adhesive layer and a base material layer forming material such as a film or a laminate layer in two or multiple layers.
It can be carried out according to any suitable manufacturing method such as.

As the coating method, for example, a roll coater method, a comma coater method, a die coater method, a reverse coater method, a silk screen method, a gravure coater method and the like can be used.

<< A-1. Base material layer ≫
The base material layer may be only one layer or two or more layers. The base material layer may be a stretched one.

The thickness of the base material layer is preferably 4 μm to 450 μm, more preferably 8 μm to 400 μm, further preferably 12 μm to 350 μm, and particularly preferably 16 μm to 250 μm.

For the surface of the base material layer to which the pressure-sensitive adhesive layer is not attached, for the purpose of forming a wound body that can be easily rewound, for example, fatty acid amide, polyethyleneimine, and a long-chain alkyl-based additive are added to the base material layer. Etc. can be added to perform mold release treatment, or a coat layer made of any suitable release agent such as silicone-based, long-chain alkyl-based, and fluorine-based can be provided.

As the material of the base material layer, any suitable material may be adopted depending on the intended use. For example, plastic, paper, metal film, non-woven fabric and the like can be mentioned. It is preferably plastic. That is, the base material layer is preferably a plastic film. The base material layer may be composed of one kind of material or may be made of two or more kinds of materials. For example, it may be composed of two or more kinds of plastics.

Examples of the plastic include polyester-based resin, polyamide-based resin, and polyolefin-based resin. Examples of the polyester-based resin include polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. Examples of the polyolefin-based resin include homopolymers of olefin monomers and copolymers of olefin monomers. Specific examples of the polyolefin-based resin include homopolypoly; a block-based, random-based, and graft-based propylene-based copolymer having an ethylene component as a copolymer; reactor TPO; low density, high density, and linear. Low-density, ultra-low-density, etc. ethylene-based copolymers; ethylene / propylene copolymer, ethylene / vinyl acetate copolymer, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / acrylic acid Examples thereof include a butyl copolymer, an ethylene / methacrylic acid copolymer, an ethylene-based copolymer such as an ethylene / methyl methacrylate copolymer; and the like.

The substrate layer may contain any suitable additives, if desired. Examples of the additive that can be contained in the base material layer include antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, fillers, pigments and the like. The type, number, and amount of additives that can be contained in the base material layer can be appropriately set according to the purpose. In particular, when the material of the base material layer is plastic, it is preferable to contain some of the above additives for the purpose of preventing deterioration and the like. From the viewpoint of improving weather resistance and the like, particularly preferable additives include antioxidants, ultraviolet absorbers, light stabilizers and fillers.

As the antioxidant, any suitable antioxidant may be employed. Examples of such antioxidants include phenol-based antioxidants, phosphorus-based processing heat stabilizers, lactone-based processing heat stabilizers, sulfur-based heat-resistant stabilizers, phenol-phosphorus-based antioxidants, and the like. The content ratio of the antioxidant is preferably 1% by weight or less, more preferably 1% by weight or less, based on the base resin of the base material layer (when the base material layer is a blend product, the blend product is the base resin). It is 0.5% by weight or less, more preferably 0.01% by weight to 0.2% by weight.

As the ultraviolet absorber, any suitable ultraviolet absorber may be adopted. Examples of such an ultraviolet absorber include a benzotriazole-based ultraviolet absorber, a triazine-based ultraviolet absorber, and a benzophenone-based ultraviolet absorber. The content ratio of the ultraviolet absorber is preferably 2% by weight or less with respect to the base resin forming the base material layer (when the base material layer is a blend product, the blend product is the base resin), and more. It is preferably 1% by weight or less, and more preferably 0.01% by weight to 0.5% by weight.

As the light stabilizer, any suitable light stabilizer may be adopted. Examples of such a light stabilizer include a hindered amine-based light stabilizer and a benzoate-based light stabilizer. The content ratio of the light stabilizer is preferably 2% by weight or less with respect to the base resin forming the base material layer (when the base material layer is a blend product, the blend product is the base resin), and more. It is preferably 1% by weight or less, and more preferably 0.01% by weight to 0.5% by weight.

As the filler, any suitable filler may be adopted. Examples of such a filler include an inorganic filler and the like. Specific examples of the inorganic filler include carbon black, titanium oxide, zinc oxide and the like. The content ratio of the filler is preferably 20% by weight or less, more preferably 20% by weight or less, based on the base resin forming the base material layer (when the base material layer is a blend product, the blend product is the base resin). Is 10% by weight or less, more preferably 0.01% by weight to 10% by weight.

Further, as the additive, inorganic-based, low-molecular-weight and high-molecular-weight antistatic agents such as surfactants, inorganic salts, polyhydric alcohols, metal compounds and carbons are also preferably mentioned for the purpose of imparting antistatic properties. In particular, from the viewpoint of contamination and maintenance of adhesiveness, high molecular weight antistatic agents and carbon are preferable.

<< A-2. Adhesive layer ≫
The pressure-sensitive adhesive layer may be composed of a pressure-sensitive adhesive. The pressure-sensitive adhesive can be formed from the pressure-sensitive adhesive composition.

The pressure-sensitive adhesive layer can be formed by any suitable method. Examples of such a method include a method in which a pressure-sensitive adhesive composition is applied onto a base material layer to form a pressure-sensitive adhesive layer on the base material layer. Examples of such a coating method include roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating method, extrusion coating by a die coater, and the like.

The thickness of the pressure-sensitive adhesive layer is preferably 1 μm to 150 μm, more preferably 2 μm to 140 μm, still more preferably 3 μm to 130 μm, still more preferably 4 μm to 120 μm, still more preferably 5 μm to 100 μm. It is more preferably 10 μm to 90 μm, particularly preferably 20 μm to 85 μm, and most preferably 30 μm to 80 μm.

The pressure-sensitive adhesive composition preferably contains a heat-resistant stabilizer. By including the heat-resistant stabilizer in the pressure-sensitive adhesive composition, not only the heat resistance is improved, but also the pressure-sensitive adhesive composition does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend. It is possible to provide a surface protective film having a large size, which can more sufficiently suppress heavy peeling over time, and has a sufficiently low stain resistance on the surface of the adherend by being attached to the adherend. This is because the heat-resistant stabilizer coexists with other components that may be contained in the pressure-sensitive adhesive composition (for example, low molecular weight polyols, silicone-based additives and / or fluorine-based additives), thereby achieving an unprecedented effect. It is presumed that this is because it can be expressed.

The heat-resistant stabilizer that can be contained in the pressure-sensitive adhesive composition may be only one kind or two or more kinds.

As the heat-resistant stabilizer, any suitable heat-resistant stabilizer can be used as long as the effects of the present invention are not impaired. Typical examples of such heat-resistant stabilizers include antioxidants, light stabilizers, heat stabilizers, and ultraviolet absorbers. The heat-resistant stabilizer is preferably an antioxidant or a light stabilizer in that the effects of the present invention can be further exhibited. Further, an antioxidant and a light stabilizer may be used in combination.

Examples of the antioxidant include a radical chain inhibitor, a peroxide decomposing agent and the like.

Examples of the radical chain inhibitor include phenol-based antioxidants and amine-based antioxidants.

Examples of the peroxide decomposing agent include sulfur-based antioxidants and phosphorus-based antioxidants.

Examples of the phenol-based antioxidant include monophenol-based antioxidants, bisphenol-based antioxidants, and polymer-type phenol-based antioxidants.

Examples of the monophenolic antioxidant include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, and stear-β- ( 3,5-Di-t-butyl-4-hydroxyphenyl) propionate and the like can be mentioned.

Examples of the bisphenol-based antioxidant include 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), and 4,4'. -Thiobis (3-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), 3,9-bis [1,1-dimethyl-2- [β-( 3-t-Butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane and the like can be mentioned.

Examples of the high molecular weight phenolic antioxidant include 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4. 6-Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane , Bis [3,3'-bis- (4'-hydroxy-3'-t-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3', 5'-di-t-butyl) -4'-Hydroxybenzyl) -S-triazine-2,4,6- (1H, 3H, 5H) trione, tocophenol and the like can be mentioned.

Examples of the sulfur-based antioxidant include dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, and distearyl 3,3'-thiodipropionate.

Examples of the phosphorus-based antioxidant include triphenylphosphine, diphenylisodecylphosphite, phenyldiisodecylphosphite and the like.

Examples of the light stabilizer include hindered amine-based light stabilizers and ultraviolet stabilizers.

Examples of the hindered amine-based light stabilizer include [bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate] and bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate. , Methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate and the like.

Examples of the ultraviolet stabilizer include nickel bis (octylphenyl) sulfide, [2,2'-thiobis (4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-tert-. Examples thereof include butyl-4-hydroxybenzyl-phosphate monoethylate, nickel-dibutyldithiocarbamate, benzoate type quencher, nickel-dibutyldithiocarbamate and the like.

Examples of the heat stabilizer include a phosphoric acid processing stabilizer, a liquid processing and heat stabilizer for polyurethane resin, a vitamin E-based processing heat stabilizer, and a sulfur-based heat stabilizer.

Examples of the ultraviolet absorber include benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, salicylic acid-based ultraviolet absorbers, oxalic acid anilide-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, and triazine-based ultraviolet absorbers. Be done.

Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, and 2,2'. -Dihydroxy-4-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy-5-benzoylphenyl) ) Examples include methane.

Examples of the benzotriazole-based ultraviolet absorber include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2- ( 2'-Hydroxy-3', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2 -(2'-Hydroxy-3', 5'-di-tert-butylphenyl) 5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl) benzotriazole, 2- (2'-Hydroxy-4'-octoxyphenyl) benzotriazole, 2- [2'-hydroxy-3'-(3'', 4'', 5'', 6'', -tetrahydrophthalimidemethyl ) -5'-Methylphenyl] benzotriazole, 2,2'methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol], [2 (2'-Hydroxy-5'-metaacryloxyphenyl) -2H-benzotriazole and the like can be mentioned.

Examples of the salicylic acid-based ultraviolet absorber include phenylsalicylate, p-tert-butylphenylsalicylate, p-octylphenylsalicylate and the like.

Examples of the cyanoacrylate-based ultraviolet absorber include 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate and ethyl-2-cyano-3,3'-diphenylacrylate.

The content ratio of the heat-resistant stabilizer in the pressure-sensitive adhesive composition is preferably 1.0% by weight to 30% by weight, more preferably 1.5% by weight to 27.5% by weight, based on 100 parts by weight of the base polymer. %, More preferably 2.0% by weight to 25% by weight, still more preferably 2.5% by weight to 22.5% by weight, still more preferably 2.75% by weight to 20% by weight. It is more preferably 3.0% by weight to 15% by weight, further preferably 3.5% by weight to 12% by weight, particularly preferably 4.0% by weight to 10% by weight, and most preferably 4 by weight. It is 5.5% by weight to 10% by weight. By adjusting the content ratio of the heat-resistant stabilizer to 100 parts by weight of the base polymer in the pressure-sensitive adhesive composition within the above range, not only the heat resistance is improved, but also the heat-resistant stabilizer can be more easily peeled off from the adherend. Even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be suppressed more sufficiently, and the contamination of the surface of the adherend by sticking to the adherend is more sufficient. A low, surface protective film can be provided.

As the heat-resistant stabilizer, a liquid heat-resistant stabilizer is preferable. The liquidity of the heat-resistant stabilizer improves dispersibility in the pressure-sensitive adhesive composition as compared to, for example, a solid heat-resistant stabilizer, which not only makes the heat-resistant stabilizer better. It does not peel off from the adherend more easily, and even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be suppressed even more sufficiently, and it can be stuck to the adherend. It is possible to provide a surface protective film having a sufficiently low contamination property on the surface of the adherend.

The heat-resistant stabilizer is preferably a heat-resistant stabilizer having a hindered phenol structure. When the heat-resistant stabilizer contains a heat-resistant stabilizer having a hindered phenol structure, the content ratio of the heat-resistant stabilizer having a hindered phenol structure in the pressure-sensitive adhesive composition is preferably 1. with respect to 100 parts by weight of the base polymer. It is 0% by weight to 30% by weight, more preferably 1.5% by weight to 27.5% by weight, still more preferably 2.0% by weight to 25% by weight, still more preferably 2.5% by weight. It is ~ 22.5% by weight, more preferably 2.75% by weight to 20% by weight, further preferably 3.0% by weight to 15% by weight, still more preferably 3.5% by weight to 12% by weight. %, Particularly preferably 4.0% by weight to 10% by weight, and most preferably 4.5% by weight to 10% by weight. By adjusting the content ratio of the heat-resistant stabilizer having a hindered phenol structure to 100 parts by weight of the base polymer in the pressure-sensitive adhesive composition within the above range, not only the heat resistance is excellent but also the heat resistance is improved from the adherend. It does not peel off more easily, and even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be more sufficiently suppressed, and the surface of the adherend by sticking to the adherend. It is possible to provide a surface protective film having a sufficiently low contamination property.

As a heat-resistant stabilizer having a hindered phenol structure, for example, a group having a large steric hindrance such as a tertiary butyl group is bonded to at least one of the adjacent carbon atoms of the carbon atom on the aromatic ring to which the OH group of phenol is bonded. Any suitable heat-resistant stabilizer may be used as long as it is a heat-resistant stabilizer having a hindered phenol structure. By using a specific heat-resistant stabilizer called a heat-resistant stabilizer having such a hindered phenol structure, not only the heat resistance is improved, but also the adherend is not easily peeled off from the adherend. Even if the initial peeling force after sticking to is large, heavy peeling over time can be suppressed more sufficiently, and the contamination of the adherend surface by sticking to the adherend is sufficiently low, surface protection. Film can be provided.

Specific examples of the heat-resistant stabilizer having a hindered phenol structure include dibutyl hydroxytoluene (BHT); trade name "IRGANOX1010" (manufactured by BASF), trade name "IRGANOX1010FF" (manufactured by BASF), and trade name "IRGANOX1035". (BASF), product name "IRGANOX1035FF" (BASF), product name "IRGANOX1076" (BASF), product name "IRGANOX1076FD" (BASF), product name "IRGANOX1076DWJ" (BASF), product name "IRGANOX1098" (BASF), product name "IRGANOX1135" (BASF), product name "IRGANOX1330" (BASF), product name "IRGANOX1726" (BASF), product name "IRGANOX1425WL" (BASF), product name "IRGANOX1520L" (BASF), product name "IRGANOX245" (BASF), product name "IRGANOX245FF" (BASF), product name "IRGANOX259" (BASF), product name "IRGANOX3114" (BASF), product name "IRGANOX565". (BASF), hindered phenolic antioxidants such as the trade name "IRGANOX295" (BASF); trade name "TINUVIN P" (BASF), trade name "TINUVIN P FL" (BASF), trade name "TINUVIN234" (manufactured by BASF), product name "TINUVIN326" (manufactured by BASF), product name "TINUVIN326FL" (manufactured by BASF), product name "TINUVIN328" (manufactured by BASF), product name "TINUVIN329" (manufactured by BASF), product name Benzotriazole-based UV absorbers such as "TINUVIN329FL" (manufactured by BASF); Liquid UV absorbers such as trade name "TINUVIN213" (manufactured by BASF) and trade name "TINUVIN571" (manufactured by BASF); trade name "TINUVIN1577ED" (manufactured by BASF) ) And other triazine-based UV absorbers; benzoate-based UV absorbers such as the trade name "TINUVIN120" (manufactured by BASF); ; And so on.

As the heat-resistant stabilizer, as described above, a liquid heat-resistant stabilizer is preferable, and a heat-resistant stabilizer having a hindered phenol structure is preferable. Therefore, a heat-resistant stabilizer that is liquid and has a hindered phenol structure, such as the trade name "IRGANOX1135" (manufactured by BASF), is more preferable.

The pressure-sensitive adhesive composition preferably comprises a base polymer.

The pressure-sensitive adhesive composition preferably contains a low molecular weight polyol.

The pressure-sensitive adhesive composition preferably contains a silicone-based additive and / or a fluorine-based additive.

The pressure-sensitive adhesive composition more preferably comprises a base polymer and a low molecular weight polyol. By including the base polymer and the low molecular weight polyol in the pressure-sensitive adhesive composition, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling after sticking to the adherend. Even if the force is large, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be exhibited.

The pressure-sensitive adhesive composition further preferably contains a base polymer, a low molecular weight polyol, and a silicone-based additive and / or a fluorine-based additive. When the pressure-sensitive adhesive composition contains a base polymer, a low molecular weight polyol, a silicone-based additive and / or a fluorine-based additive, the surface protective film of the present invention may be more easily peeled off from the adherend. Even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be suppressed more sufficiently, and the contamination of the surface of the adherend by sticking to the adherend is more sufficient. The effect of being low can be exhibited.

In a preferred embodiment of the present invention, when a low molecular weight polyol is used in combination with a silicone-based additive and / or a fluorine-based additive, it does not peel off more easily from the adherend and is initially attached to the adherend. A surface protective film that can more sufficiently suppress heavy peeling over time even if the peeling force of the film is large, and can further exhibit the effect that the contamination of the surface of the adherend by being attached to the adherend is sufficiently low. Can be provided.

The content ratio of the total amount of the base polymer, the low molecular weight polyol, the silicone-based additive and the fluorine-based additive in the pressure-sensitive adhesive composition is preferably 50% by weight to 100% by weight, more preferably 60% by weight. It is ~ 100% by weight, more preferably 70% by weight to 100% by weight, particularly preferably 75% by weight to 100% by weight, and most preferably 80% by weight to 100% by weight. When the content ratio of the total amount of the base polymer, the silicone-based additive and the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention can be easily peeled off from the adherend. Even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be sufficiently suppressed, and the surface of the adherend is sufficiently contaminated by sticking to the adherend. The effect of being low can be more exhibited.

The content of the low molecular weight polyol in the pressure-sensitive adhesive composition is preferably 0.01 parts by weight to 50 parts by weight, more preferably 0.05 parts by weight to 25 parts by weight, based on 100 parts by weight of the base polymer. It is more preferably 0.07 parts by weight to 30 parts by weight, further preferably 0.1 parts by weight to 20 parts by weight, still more preferably 0.3 parts by weight to 15 parts by weight, and particularly preferably. It is 0.5 parts by weight to 10 parts by weight, and most preferably 0.7 parts by weight to 7.0 parts by weight. When the content of the low molecular weight polyol in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is initially attached to the adherend. Even if the peeling force is large, the heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

The content of the silicone-based additive and / or the fluorine-based additive in the pressure-sensitive adhesive composition is preferably 0.001 part by weight as the total amount of the silicone-based additive and the fluorine-based additive with respect to 100 parts by weight of the base polymer. ~ 50 parts by weight, more preferably 0.005 parts by weight to 25 parts by weight, further preferably 0.01 parts by weight to 10 parts by weight, still more preferably 0.01 parts by weight to 1 part by weight. It is more preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0.10 parts by weight. Is. When the content of the silicone-based additive and / or the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is adhered. Even if the initial peeling force after sticking to the body is large, it is possible to more sufficiently suppress heavy peeling over time, and the effect of sticking to the adherend is that the contamination of the surface of the adherend is sufficiently low. Can be more expressed.

That is, when the pressure-sensitive adhesive composition contains a silicone-based additive but does not contain a fluorine-based additive, the content ratio of the silicone-based additive to 100 parts by weight of the base polymer is preferably 0.001 part by weight to 50 parts by weight. Parts, more preferably 0.005 parts by weight to 25 parts by weight, still more preferably 0.01 parts by weight to 10 parts by weight, still more preferably 0.01 parts by weight to 1 part by weight, and further. It is preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0.10 parts by weight. When the content of the silicone-based additive in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and after being attached to the adherend, Even if the initial peeling force is large, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

When the pressure-sensitive adhesive composition does not contain a silicone-based additive but contains a fluorine-based additive, the content ratio of the fluorine-based additive to 100 parts by weight of the base polymer is preferably 0.001 part by weight to 50 parts by weight. Parts, more preferably 0.005 parts by weight to 25 parts by weight, still more preferably 0.01 parts by weight to 10 parts by weight, still more preferably 0.01 parts by weight to 1 part by weight, and further. It is preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0.10 parts by weight. When the content of the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and after being attached to the adherend, Even if the initial peeling force is large, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

When both the silicone-based additive and the fluorine-based additive are contained in the pressure-sensitive adhesive composition, the total content ratio of the silicone-based additive and the fluorine-based additive to 100 parts by weight of the base polymer is preferably 0. It is 001 parts by weight to 50 parts by weight, more preferably 0.005 parts by weight to 25 parts by weight, further preferably 0.01 parts by weight to 10 parts by weight, still more preferably 0.01 parts by weight to 1 part. It is parts by weight, more preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0 parts by weight. It is 10 parts by weight. When the total content of the silicone-based additive and the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is adhered. Even if the initial peeling force after sticking to the body is large, it is possible to more sufficiently suppress heavy peeling over time, and the effect of sticking to the adherend is that the contamination of the surface of the adherend is sufficiently low. Can be more expressed.

The silicone-based additive and / or the fluorine-based additive preferably contains a hydroxyl group-containing fluorine-based compound and / or a hydroxyl group-containing silicone-based compound indispensably from the viewpoint of further exhibiting the effects of the present invention. That is, preferred embodiments of the silicone-based additive and / or the fluorine-based additive include (1) a form containing a hydroxyl group-containing fluorine-based compound indispensably and not containing a hydroxyl group-containing silicone-based compound, and (2) a hydroxyl group-containing silicone-based compound. It is a form that is essential and does not contain a hydroxyl group-containing fluorine compound, and (3) a form that contains both a hydroxyl group-containing fluorine compound and a hydroxyl group-containing silicone compound as essential. In the case of the above form (1), the content ratio of the hydroxyl group-containing fluorine-based compound in the total amount of the silicone-based additive and the fluorine-based additive is preferably 50% by weight or more in that the effect of the present invention can be more exhibited. It is 100% by weight, more preferably 70% by weight to 100% by weight, still more preferably 90% by weight to 100% by weight, particularly preferably 95% by weight to 100% by weight, and most preferably substantially. It is 100% by weight. In the case of the above form (2), the content ratio of the hydroxyl group-containing silicone-based compound in the total amount of the silicone-based additive and the fluorine-based additive is preferably 50% by weight or more in that the effect of the present invention can be more exhibited. It is 100% by weight, more preferably 70% by weight to 100% by weight, still more preferably 90% by weight to 100% by weight, particularly preferably 95% by weight to 100% by weight, and most preferably substantially. It is 100% by weight. In the case of the above form (3), the total content ratio of both the hydroxyl group-containing fluorine-based compound and the hydroxyl group-containing silicone-based compound in the total amount of the silicone-based additive and the fluorine-based additive further exhibits the effect of the present invention. In terms of gain, it is preferably 50% by weight to 100% by weight, more preferably 70% by weight to 100% by weight, still more preferably 90% by weight to 100% by weight, and particularly preferably 95% by weight to 100% by weight. It is% by weight, most preferably substantially 100% by weight.

<A-2-1. Base polymer>
The base polymer is preferably at least one selected from urethane prepolymers, polyols, acrylic resins, rubber resins, and silicone resins. If the base polymer is at least one selected from urethane prepolymers, polyols, acrylic resins, rubber resins, and silicone resins, the surface protective film of the present invention will not be more easily peeled off from the adherend. Even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be suppressed more sufficiently, and the contamination of the surface of the adherend by sticking to the adherend is more sufficient. The effect of being low can be more exhibited.

[A-2-1-a. Urethane prepolymer]
The urethane prepolymer is preferably a polyurethane polyol, and more preferably a polyester polyol (a1) or a polyether polyol (a2), respectively, alone or in a mixture of (a1) and (a2), in the presence of a catalyst. It is formed by reacting with the organic polyisocyanate compound (a3) under or without a catalyst.

As the polyester polyol (a1), any suitable polyester polyol can be used. Examples of such a polyester polyol (a1) include a polyester polyol obtained by reacting an acid component with a glycol component. Examples of the acid component include terephthalic acid, adipic acid, azelaic acid, sebatic acid, phthalic anhydride, isophthalic acid, trimellitic acid and the like. Examples of the glycol component include ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1,6-hexaneglycol, 3-methyl-1,5-pentanediol, 3,3'-dimethylolheptan, and polyoxyethylene glycol. Examples thereof include polyoxypropylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, and polyol components such as glycerin, trimethylolpropane, and pentaerythritol. Examples of the polyester polyol (a1) also include a polyester polyol obtained by ring-opening polymerization of lactones such as polycaprolactone, poly (β-methyl-γ-valerolactone) and polyvalerolactone.

The polyester polyol (a1) can be used from a low molecular weight to a high molecular weight. As the molecular weight of the polyester polyol (a1), the number average molecular weight Mn is preferably 100 to 100,000. If the number average molecular weight Mn is less than 100, the reactivity becomes high and gelation may easily occur. If the number average molecular weight Mn exceeds 100,000, the reactivity may be lowered, and the cohesive force of the polyurethane polyol itself may be reduced. The amount of the polyester polyol (a1) used is preferably 0 mol% to 90 mol% in the polyol constituting the polyurethane polyol.

As the polyether polyol (a2), any suitable polyether polyol can be used. Examples of such a polyether polyol (a2) include ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran using a low molecular weight polyol such as water, propylene glycol, ethylene glycol, glycerin, and trimethylolpropane as an initiator. Examples thereof include polyether polyols obtained by polymerizing an oxylan compound. Specific examples of such a polyether polyol (a2) include polyether polyols having 2 or more functional groups, such as polypropylene glycol, polyethylene glycol, and polytetramethylene glycol.

The molecular weight of the polyether polyol (a2) can be from low molecular weight to high molecular weight. As the molecular weight of the polyether polyol (a2), the number average molecular weight Mn is preferably 100 to 100,000. If the number average molecular weight Mn is less than 100, the reactivity becomes high and gelation may easily occur. If the number average molecular weight Mn exceeds 100,000, the reactivity may be lowered, and the cohesive force of the polyurethane polyol itself may be reduced. The amount of the polyether polyol (a2) used is preferably 0 mol% to 90 mol% in the polyol constituting the polyurethane polyol.

If necessary, the polyether polyol (a2) may be partially composed of glycols such as ethylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane, and pentaerythritol. It can be used in combination with polyvalent amines such as ethylenediamine, N-aminoethylethanolamine, isophoronediamine, and xylylenediamine.

As the polyether polyol (a2), only a bifunctional polyether polyol may be used, or a poly having a number average molecular weight Mn of 100 to 100,000 and having at least 3 or more hydroxyl groups in one molecule. Part or all of the ether polyol may be used. When a part or all of the polyether polyol having a number average molecular weight Mn of 100 to 100,000 and having at least 3 or more hydroxyl groups in one molecule is used as the polyether polyol (a2), the adhesive strength and the removability are removable. Can be well-balanced. In such a polyether polyol, if the number average molecular weight Mn is less than 100, the reactivity becomes high and gelation may easily occur. Further, in such a polyether polyol, if the number average molecular weight Mn exceeds 100,000, the reactivity may be lowered, and further, the cohesive force of the polyurethane polyol itself may be reduced. The number average molecular weight Mn of such a polyether polyol is more preferably 100 to 10,000.

As the organic polyisocyanate compound (a3), any suitable organic polyisocyanate compound can be used. Examples of such an organic polyisocyanate compound (a3) include aromatic polyisocyanates, aliphatic polyisocyanates, aromatic aliphatic polyisocyanates, and alicyclic polyisocyanates.

Examples of the aromatic polyisocyanate include 1,3-phenylenediocyanate, 4,4'-diphenyldiisocyanate, 1,4-phenylenediocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, and 2,6. -Tolylene diisocyanate, 4,4'-toluene diisocyanate, 2,4,6-triisocyanate toluene, 1,3,5-triisocyanate benzene, dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4', Examples thereof include 4 "-triphenylmethane triisocyanate.

Examples of the aliphatic polyisocyanate include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylenediocyanate, 1,3-butylenediocyanate, and dodecamethylene diisocyanate. Examples thereof include 2,4,4-trimethylhexamethylene diisocyanate.

Examples of the aromatic aliphatic polyisocyanate include ω, ω'-diisocyanate-1,3-dimethylbenzene, ω, ω'-diisocyanate-1,4-dimethylbenzene, ω, ω'-diisocyanate-1,4-diethylbenzene. , 1,4-Tetramethylxylylene diisocyanate, 1,3-tetramethylxylylene diisocyanate and the like.

Examples of the alicyclic polyisocyanate include 3-isocyanate methyl-3,5,5-trimethylcyclohexylisocyanate, 1,3-cyclopentanediisocyanate, 1,3-cyclohexanediisocyanate, 1,4-cyclohexanediisocyanate, and methyl-2. , 4-Cyclohexanediisocyanate, Methyl-2,6-Cyclohexanediisocyanate, 4,4'-Methylenebis (cyclohexylisocyanate), 1,4-bis (isocyanatemethyl) cyclohexane, 1,4-bis (isocyanatemethyl) cyclohexane and the like. Be done.

As the organic polyisocyanate compound (a3), a trimethylolpropane adduct compound, a biuret compound reacted with water, a trimer having an isocyanurate ring, or the like can be used in combination.

As the catalyst that can be used in obtaining the polyurethane polyol, any suitable catalyst can be used. Examples of such a catalyst include tertiary amine compounds and organometallic compounds.

Examples of the tertiary amine compound include triethylamine, triethylenediamine, 1,8-diazabicyclo (5,4,0) -undecene-7 (DBU) and the like.

Examples of the organometallic compound include tin-based compounds and non-tin-based compounds.

Examples of the tin-based compound include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimalate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, and tributyl. Examples thereof include tin acetate, triethyl tin ethoxide, tributyl tin ethoxide, dioctyl tin oxide, tributyl tin chloride, tributyl tin trichloroacetate, tin 2-ethylhexanoate and the like.

Examples of the non-tin compound include titanium compounds such as dibutyl titanium dichloride, tetrabutyl titanate, and butoxytitanium trichloride; lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate. Iron compounds such as iron 2-ethylhexanoate and iron acetylacetonate; Cobalt compounds such as cobalt benzoate and cobalt 2-ethylhexanate; Zinc compounds such as zinc naphthenate and zinc 2-ethylhexanate; Zylon-based compounds such as zirconium naphthenate; and the like.

When a catalyst is used to obtain a polyurethane polyol, in a system in which two types of polyols, a polyester polyol and a polyether polyol, are present, the reactivity is different. Therefore, in a single catalyst system, gelation or a reaction solution may occur. The problem of turbidity is likely to occur. Therefore, by using two kinds of catalysts when obtaining the polyurethane polyol, the reaction rate, the selectivity of the catalyst and the like can be easily controlled, and these problems can be solved. Examples of the combination of such two types of catalysts include tertiary amine / organic metal-based, tin-based / non-tin-based, and tin-based / tin-based, preferably tin-based / tin-based, and more preferably. Is a combination of dibutyltin dilaurate and tin 2-ethylhexanoate. As for the compounding ratio, the tin 2-ethylhexanoate / dibutyltin dilaurate is preferably less than 1 and more preferably 0.2 to 0.6 by weight. When the compounding ratio is 1 or more, gelation may easily occur due to the balance of catalytic activity.

When a catalyst is used in obtaining a polyurethane polyol, the amount of the catalyst used is preferably 0.01 with respect to the total amount of the polyester polyol (a1), the polyether polyol (a2) and the organic polyisosianate compound (a3). It is from% by weight to 1.0% by weight.

When a catalyst is used in obtaining the polyurethane polyol, the reaction temperature is preferably less than 100 ° C, more preferably 85 ° C to 95 ° C. If the temperature is 100 ° C. or higher, it may be difficult to control the reaction rate and the crosslinked structure, and it may be difficult to obtain a polyurethane polyol having a predetermined molecular weight.

A catalyst may not be used to obtain the polyurethane polyol. In that case, the reaction temperature is preferably 100 ° C. or higher, more preferably 110 ° C. or higher. Further, when the polyurethane polyol is obtained without a catalyst, it is preferable to react for 3 hours or more.

As a method for obtaining a polyurethane polyol, for example, 1) a method of charging a polyester polyol, a polyether polyol, a catalyst, and an organic polyisocyanate into a flask in full quantity, and 2) a method of charging a polyester polyol, a polyether polyol, and a catalyst into a flask and charging an organic polyisocianate. There is a method of adding the polyol by dropping it. As a method for obtaining a polyurethane polyol, the method 2) is preferable in controlling the reaction.

Any suitable solvent may be used in obtaining the polyurethane polyol. Examples of such a solvent include methyl ethyl ketone, ethyl acetate, toluene, xylene, acetone and the like. Among these solvents, toluene is preferable.

[A2-1-1b. Polyol]
Examples of the polyol include polyester polyol, polyether polyol, polycaprolactone polyol, polycarbonate polyol, and castor oil-based polyol. The polyol is more preferably a polyether polyol.

The polyester polyol can be obtained, for example, by an esterification reaction between a polyol component and an acid component.

Examples of the polyol component include ethylene glycol, diethylene glycol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, and 2-butyl-2-ethyl-1. , 3-Propanediol, 2,4-diethyl-1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 2-methyl Examples thereof include -1,8-octanediol, 1,8-decanediol, octadecanediol, glycerin, trimethylolpropane, pentaerythritol, hexanetriol and polypropylene glycol. Examples of the acid component include succinic acid, methylsuccinic acid, adipic acid, piceric acid, azelaic acid, sebacic acid, 1,12-dodecanedioic acid, 1,14-tetradecanedioic acid, dimer acid, 2-methyl-1, 4-Cyclohexanedicarboxylic acid, 2-ethyl-1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 4,4'-biphereldicarboxylic acid , These acid anhydrides and the like.

Examples of the polyether polyol include water, low molecular weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol A, etc.), dihydroxybenzene (catechol, resorcin, hydroquinone, etc.), etc. Examples thereof include a polyether polyol obtained by addition-polymerizing an alkylene oxide such as ethylene oxide, propylene oxide, and butylene oxide. Specific examples thereof include polyethylene glycol, polypropylene glycol and polytetramethylene glycol.

Examples of the polycaprolactone polyol include a caprolactone-based polyester diol obtained by ring-opening polymerization of a cyclic ester monomer such as ε-caprolactone and σ-valerolactone.

Examples of the polycarbonate polyol include a polycarbonate polyol obtained by subjecting the above-mentioned polyol component and phosgen to a polycondensation reaction; the above-mentioned polyol component and dimethyl carbonate, diethyl carbonate, diprovyl carbonate, diisopropyl carbonate, dibutyl carbonate, ethylbutylcarbonate, ethylene carbonate, Polycarbonate polyol obtained by ester exchange condensation with carbonic acid diesters such as propylene carbonate, diphenyl carbonate, dibenzyl carbonate; copolymerized polycarbonate polyol obtained by using two or more of the above polyol components in combination; containing various polycarbonate polyols and a carboxyl group. Polycarbonate polyol obtained by esterifying a compound; Polycarbonate polyol obtained by etherifying a various polycarbonate polyols and a hydroxyl group-containing compound; Obtaining by an ester exchange reaction between various polycarbonate polyols and an ester compound. Polycarbonate polyol; Polycarbonate polyol obtained by performing an ester exchange reaction between the various polycarbonate polyols and a hydroxyl group-containing compound; Polycarbonate-based polycarbonate polyol obtained by a polycondensation reaction between the various polycarbonate polyols and a dicarboxylic acid compound; Examples thereof include a copolymerized polyether polycarbonate polyol obtained by copolymerizing and alkylene oxide.

Examples of the castor oil-based polyol include castor oil-based polyol obtained by reacting a castor oil fatty acid with the above-mentioned polyol component. Specific examples thereof include castor oil-based polyols obtained by reacting castor oil fatty acid with polypropylene glycol.

The number average molecular weight Mn of the polyol is preferably 300 to 100,000, more preferably 400 to 75,000, still more preferably 450 to 50,000, and particularly preferably 500 to 30,000. When the number average molecular weight Mn of the polyol is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend is large. However, it is possible to more sufficiently suppress heavy peeling over time, and it is possible to exhibit the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low.

The polyol preferably contains a polyol (A1) having three OH groups and having a number average molecular weight Mn of 300 to 100,000. The polyol (A1) may be only one kind or two or more kinds.

The content ratio of the polyol (A1) in the polyol is preferably 5% by weight or more, more preferably 25% by weight to 100% by weight, and further preferably 50% by weight to 100% by weight. When the content ratio of the polyol (A1) in the polyol is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is initially peeled off after being attached to the adherend. Even if the force is large, heavy exfoliation over time can be more sufficiently suppressed, and the effect that the surface of the adherend is sufficiently less contaminated by being attached to the adherend can be further exhibited.

The number average molecular weight Mn of the polyol (A1) is preferably 1000 to 100,000, more preferably more than 1000 and not more than 80,000, still more preferably 1100 to 70000, still more preferably 1200 to 60000, and further. It is preferably 1300 to 50000, more preferably 1400 to 40000, still more preferably 1500 to 35000, particularly preferably 1700 to 32000, and most preferably 2000 to 30000. When the number average molecular weight Mn of the polyol (A1) is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend. Even if the size is large, heavy exfoliation over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

The polyol may contain a polyol (A2) having 3 or more OH groups and having a number average molecular weight Mn of 20000 or less. The polyol (A2) may be only one kind or two or more kinds. The number average molecular weight Mn of the polyol (A2) is preferably 100 to 20000, more preferably 150 to 10000, still more preferably 200 to 7500, particularly preferably 300 to 6000, and most preferably 300. ~ 5000. If the number average molecular weight Mn of the polyol (A2) is out of the above range, the peeling force of the surface protective film of the present invention may increase with time. The polyol (A2) is preferably a polyol having 3 OH groups (triol), a polyol having 4 OH groups (tetraol), a polyol having 5 OH groups (pentaol), and 6 OH groups. Examples thereof include a polyol (hexaol) having.

The total amount of the polyol (A2), which is a polyol having 4 OH groups (tetraol), a polyol having 5 OH groups (pentaol), and a polyol having 6 OH groups (hexaol), is in the polyol. The content ratio is preferably 70% by weight or less, more preferably 60% by weight or less, further preferably 40% by weight or less, and particularly preferably 30% by weight or less. The total amount of the polyol (A2) in the polyol is a polyol having 4 OH groups (tetraol), a polyol having 5 OH groups (pentaol), and a polyol having 6 OH groups (hexaol). When the content ratio in the polyol is within the above range, a pressure-sensitive adhesive layer having excellent transparency can be provided, and the surface protective film of the present invention does not peel off from the adherend more easily, and the adherend is not peeled off more easily. Even if the initial peeling force after sticking to is large, it is possible to more sufficiently suppress heavy peeling over time, and the effect of sticking to the adherend is that the contamination of the surface of the adherend is sufficiently low. Can be more expressed.

The content ratio of the polyol (A2) in the polyol is preferably 95% by weight or less, and more preferably 0% by weight to 75% by weight. When the content ratio of the polyol (A2) in the polyol is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is initially peeled off after being attached to the adherend. Even if the force is large, heavy exfoliation over time can be more sufficiently suppressed, and the effect that the surface of the adherend is sufficiently less contaminated by being attached to the adherend can be exhibited.

The content ratio of the polyol (A2) having 4 or more OH groups and having a number average molecular weight Mn of 20000 or less is preferably less than 70% by weight, more preferably 60% by weight or less, based on the total amount of the polyol. It is more preferably 50% by weight or less, particularly preferably 40% by weight or less, and most preferably 30% by weight or less. If the content ratio of the polyol (A2) having four or more OH groups and having a number average molecular weight Mn of 20000 or less is within the above range with respect to the entire polyol, a pressure-sensitive adhesive layer having excellent transparency is provided. Further, the surface protective film of the present invention does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, the heavy peeling over time is more sufficient. It can be suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be further exhibited.

[A2-1-1c. Acrylic resin]
As the acrylic resin, any suitable acrylic pressure-sensitive adhesive such as the known acrylic pressure-sensitive adhesive described in JP2013-241606 can be adopted as long as the effect of the present invention is not impaired.

The acrylic resin may contain any suitable component as long as the effect of the present invention is not impaired. Examples of such components include resin components other than acrylic resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and ultraviolet absorbers. Examples thereof include agents, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts and the like.

[A2-1-1d. Rubber resin]
As the rubber-based resin, any suitable rubber-based pressure-sensitive adhesive such as a known rubber-based pressure-sensitive adhesive described in JP-A-2015-074771 can be adopted as long as the effects of the present invention are not impaired. These may be only one kind or two or more kinds.

The rubber-based resin may contain any suitable component as long as the effect of the present invention is not impaired. Examples of such components include resin components other than rubber-based resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and ultraviolet absorbers. Examples thereof include agents, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts and the like.

[A2-1-1e. Silicone resin]
As the silicone-based resin, any suitable silicone-based pressure-sensitive adhesive such as the known silicone-based pressure-sensitive adhesive described in JP-A-2014-047280 can be adopted as long as the effects of the present invention are not impaired. These may be only one kind or two or more kinds.

The silicone-based resin may contain any suitable component as long as the effect of the present invention is not impaired. Examples of such components include resin components other than silicone-based resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and ultraviolet absorbers. Examples thereof include agents, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts and the like.

<A-2-2. Low molecular weight polyol>
The low molecular weight polyol may be only one kind or two or more kinds.

As the low molecular weight polyol, any suitable low molecular weight polyol may be adopted as long as the effect of the present invention is not impaired. As such a low molecular weight polyol, preferably, a polyol having a number average molecular weight Mn of 1500 or less can be mentioned.

The number average molecular weight Mn of the low molecular weight polyol is preferably 1400 or less, more preferably 1300 or less, still more preferably 1200 or less, particularly preferably 1100 or less, and most preferably 1000 or less. The lower limit of the number average molecular weight Mn of the low molecular weight polyol is preferably 50 or more, more preferably 80 or more, still more preferably 100 or more, and particularly preferably 120 or more. When the number average molecular weight Mn of the low molecular weight polyol is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend is high. Even if it is large, it is possible to more sufficiently suppress heavy peeling over time, and it is possible to further exhibit the effect that the contamination of the surface of the adherend by attaching it to the adherend is sufficiently low.

Examples of the low molecular weight polyols include polyester polyols, polyether polyols, polycaprolactone polyols, polycarbonate polyols, and castor oil-based polyols. The low molecular weight polyol is more preferably a polyether polyol.

Examples of the polyether polyol include water, low molecular weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol A, etc.), dihydroxybenzene (catechol, resorcin, hydroquinone, etc.), etc. Examples thereof include a polyether polyol obtained by addition-polymerizing an alkylene oxide such as ethylene oxide, propylene oxide, and butylene oxide. Specific examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxypropylene glyceryl ether and the like.

The number of OH groups contained in the low molecular weight polyol is preferably 2 to 6, more preferably 3 to 5, still more preferably 3 to 4, and particularly preferably 3. .. When the number of OH groups contained in the low molecular weight polyol is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and has an initial peeling force after being attached to the adherend. Even if it is large, it is possible to more sufficiently suppress heavy peeling over time, and it is possible to exhibit the effect that the contamination of the surface of the adherend by attaching it to the adherend is sufficiently low.

<A-2-3. Silicone additives>
As the silicone-based additive, any suitable silicone-based additive can be adopted as long as the effect of the present invention is not impaired. Examples of such a silicone-based additive include at least one selected from a siloxane bond-containing compound, a hydroxyl group-containing silicone-based compound, and a crosslinkable functional group-containing silicone-based compound, and more preferably a hydroxyl group-containing silicone-based compound. It is a compound.

The silicone-based additive may be only one kind or two or more kinds.

Examples of the siloxane bond-containing compound include a polyether-modified polyorganosiloxane having a polyether group introduced into the main chain or side chain of a polyorganosiloxane skeleton (polydimethylsiloxane, etc.), and a main chain or side chain of a polyorganosiloxane skeleton. Polyester-modified polyorganosiloxane with a polyester group introduced, organic compound-introduced polyorganosiloxane with an organic compound introduced into the main or side chains of the polyorganosiloxane skeleton, and silicone-modified with polyorganosiloxane introduced into a (meth) acrylic resin (meth) Meta) Examples include acrylic resins, silicone-modified organic compounds in which polyorganosiloxane is introduced into organic compounds, and silicone-containing organic compounds obtained by copolymerizing an organic compound and a silicone compound. Examples of such siloxane bond-containing polymers as commercial products include the brand name "LE-302" (manufactured by Kyoeisha Chemical Co., Ltd.) and the BYK series leveling agent manufactured by Big Chemie Japan Co., Ltd. ("BYK-300"). , "BYK-301 / 302", "BYK-306", "BYK-307", "BYK-310", "BYK-315", "BYK-313", "BYK-320", "BYK-322" , "BYK-323", "BYK-325", "BYK-330", "BYK-331", "BYK-333", "BYK-337", "BYK-341", "BYK-344", "BYK-345 / 346", "BYK-347", "BYK-348", "BYK-349", "BYK-370", "BYK-375", "BYK-377", "BYK-378", "BYK-UV3500", "BYK-UV3510", "BYK-UV3570", "BYK-3550", "BYK-SILCLEAN3700", "BYK-SILCLEAN3720", etc.), AC series leveling agent manufactured by Algin Chemie ("" AC FS180 ”,“ AC FS360 ”,“ AC S20 ”, etc.), Polyflow series leveling agents manufactured by Kyoeisha Chemical Co., Ltd. (“Polyflow KL-400X”, “Polyflow KL-400HF”, “Polyflow KL-401” , "Polyflow KL-402", "Polyflow KL-403", "Polyflow KL-404", etc.), KP series leveling agents manufactured by Shin-Etsu Chemical Co., Ltd. ("KP-323", "KP-326", "KP-341", "KP-104", "KP-110", "KP-112", etc.), Shin-Etsu Chemical's X22 series, KF series, etc., Toray Dow Corning Co., Ltd. leveling agents ( "LP-7001", "LP-7002", "8032ADDITIVE", "57ADDITIVE", "L-7604", "FZ-2110", "FZ-2105", "67ADDITIVE", "8618ADDITIVE", "3ADDITIVE", "56 ADDITIVE" etc.) and the like.

Examples of the hydroxyl group-containing silicone compound include a polyether-modified polyorganosiloxane having a polyether group introduced into the main chain or side chain of a polyorganosiloxane skeleton (polydimethylsiloxane, etc.), and a main chain or side chain of a polyorganosiloxane skeleton. Polyorganosiloxane with a polyester group introduced into it, polyorganosiloxane with an organic compound introduced into the main chain or side chain of the polyorganosiloxane skeleton, and silicone modification with polyorganosiloxane introduced into a (meth) acrylic resin. Examples thereof include (meth) acrylic resins, silicone-modified organic compounds in which polyorganosiloxane is introduced into organic compounds, and silicone-containing organic compounds obtained by copolymerizing an organic compound and a silicone compound. In these, the hydroxyl group may be contained in a polyorganosiloxane skeleton, or may be contained in a polyether group, a polyester group, a (meth) acryloyl group, or an organic compound. Examples of commercially available products such as the hydroxyl group-containing silicone compound include trade names "X-22-4015", "X-22-4039", "KF6000", "KF6001", "KF6002", and "KF6003". , "X-22-170BX", "X-22-170DX", "X-22-176DX", "X-22-176F" (manufactured by Shin-Etsu Chemical Co., Ltd.), manufactured by Big Chemie Japan Co., Ltd. Examples thereof include "BYK-370", "BYK-SILCLEAN3700", and "BYK-SILCLEAN3720".

Examples of the crosslinkable functional group-containing silicone compound include polyether-modified polyorganosiloxane and polyorganosiloxane skeleton in which a polyether group is introduced into the main chain or side chain of a polyorganosiloxane skeleton (polydimethylsiloxane, etc.). Polyester-modified polyorganosiloxane with a polyester group introduced into the chain or side chain, organic compound-introduced polyorganosiloxane with an organic compound introduced into the main chain or side chain of the polyorganosiloxane skeleton, and polyorganosiloxane in a (meth) acrylic resin. Examples thereof include the introduced silicone-modified (meth) acrylic resin, the silicone-modified organic compound in which polyorganosiloxane is introduced into the organic compound, and the silicone-containing organic compound obtained by copolymerizing the organic compound and the silicone compound. In these, the crosslinkable functional group may be contained in a polyorganosiloxane skeleton, or may be contained in a polyether group, a polyester group, a (meth) acryloyl group, or an organic compound. Examples of the crosslinkable functional group include an amino group, an epoxy group, a mercapto group, a carboxyl group, an isocyanate group, and a methacrylate group. Examples of such isocyanate group-containing silicones as commercially available products include "BY16-855", "SF8413", "BY16-839", "SF8421", and "BY16-750" manufactured by Toray Dow Corning Co., Ltd. , "BY16-880", "BY16-152C", "KF-868", "KF-865", "KF-864", "KF-859", "KF-393" manufactured by Shin-Etsu Chemical Co., Ltd. , "KF-860", "KF-880", "KF-8004", "KF-8002", "KF-8005", "KF-867", "KF-8021", "KF-869", " KF-861 "," X-22-343 "," KF-101 "," X-22-2000 "," X-22-4741 "," KF-1002 "," KF-2001 "," X- 22-3701E ”,“ X-22-164 ”,“ X-22-164A ”,“ X-22-164B ”,“ X-22-164AS ”,“ X-22-2445 ”and the like.

<A-2-4. Fluorine-based additives>
As the fluorine-based additive, any suitable fluorine-based additive can be adopted as long as the effect of the present invention is not impaired. As such a fluorine-based additive, preferably, at least one selected from a fluorine-containing compound, a hydroxyl group-containing fluorine-based compound, and a crosslinkable functional group-containing fluorine-based compound can be mentioned. A hydroxyl group-containing fluorine-based compound is preferable because the effects of the present invention can be further exhibited.

The fluorine-based additive may be only one kind or two or more kinds.

Examples of the fluorine-containing compound include a compound having a fluoroaliphatic hydrocarbon skeleton, a fluorine-containing organic compound obtained by copolymerizing an organic compound and a fluorine compound, and a fluorine-containing compound containing an organic compound. Examples of the fluoroaliphatic hydrocarbon skeleton include fluoroC1-C10 alkanes such as fluoromethane, fluoroethane, fluoropropane, fluoroisopropane, fluorobutane, fluoroisobutane, fluorot-butane, fluoropentane, and fluorohexane. Be done. As such a fluorine-containing compound, as a commercially available product, for example, a leveling agent of the Surflon series manufactured by AGC Seimi Chemical Co., Ltd. (“S-242”, “S-243”, “S-420”, “S-420”, “ S-611 "," S-651 "," S-386 ", etc.), BYK series leveling agent manufactured by Big Chemie Japan Co., Ltd. (" BYK-340 ", etc.), AC series leveling manufactured by Algin Chemie. Agents ("AC 110a", "AC 100a", etc.), leveling agents of the Megafuck series manufactured by DIC Co., Ltd. ("Megafuck F-114", "Megafuck F-410", "Megafuck F-444"" , "Mega Fuck EXP TP-2066", "Mega Fuck F-430", "Mega Fuck F-472SF", "Mega Fuck F-477", "Mega Fuck F-552", "Mega Fuck F-553", "Mega Fuck F-554", "Mega Fuck F-555", "Mega Fuck R-94", "Mega Fuck RS-72-K", "Mega Fuck RS-75", "Mega Fuck F-556", "Mega Fuck EXP TF-1637", "Mega Fuck EXP TF-1437", "Mega Fuck F-558", "Mega Fuck EXP TF-1537", etc.), FC series leveling agent manufactured by Sumitomo 3M Co., Ltd. ( "FC-4430", "FC-4432", etc.), Leveling agent of the Futagent series manufactured by Neos Co., Ltd. , "Futagent 150CH", "Futagent AK", "Futagent 501", "Futagent 250", "Futagent 251", "Futagent 222F", "Futagent 208G", "Futagent 300" , "Futagent 310", "Futagent 400SW", etc.), PF series leveling agents manufactured by Kitamura Chemical Industry Co., Ltd. ("PF-136A", "PF-156A", "PF-151N", "PF-" 636 ”,“ PF-6320 ”,“ PF-656 ”,“ PF-6520 ”,“ PF-651 ”,“ PF-652 ”,“ PF-3320 ”, etc.) and the like.

As the hydroxyl group-containing fluoropolymer, for example, a conventionally known resin can be used. For example, International Publication No. 94/06870, JP-A-8-12921, JP-A-10-72569, JP-A-4-275379 Examples thereof include the hydroxyl group-containing fluororesins described in Japanese Patent Publication No. 97/11130 Pamphlet, International Publication No. 96/26254 Pamphlet and the like. Examples of other hydroxyl group-containing fluororesins include fluoroolefins described in JP-A-8-231919, JP-A-10-265731, JP-A-10-204374, JP-A-8-12922, and the like. Examples include polymers. In addition, a copolymer of a compound having a fluorinated alkyl group in a hydroxyl group-containing compound, a fluorine-containing organic compound obtained by copolymerizing a fluorine-containing compound with a hydroxyl group-containing compound, a fluorine-containing compound containing a hydroxyl group-containing organic compound, and the like can be mentioned. Examples of commercially available products such as the hydroxyl group-containing fluorine-based compound include the trade name "Lumiflon" (manufactured by Asahi Glass Co., Ltd.), the trade name "Cefral Coat" (manufactured by Central Glass Co., Ltd.), and the trade name "Zaflon". (Manufactured by Toa Synthetic Co., Ltd.), trade name "Zeffle" (manufactured by Daikin Industries, Ltd.), trade name "Megafuck F-571", "Fluonate" (manufactured by DIC Co., Ltd.) and the like.

Examples of the crosslinkable functional group-containing fluorine-based compound include a carboxylic acid compound having a fluorinated alkyl group such as perfluorooctanoic acid, and a compound having a fluorinated alkyl group in the crosslinkable functional group-containing compound. Examples thereof include a fluoropolymer, a fluorine-containing organic compound obtained by copolymerizing a fluorine-containing compound with a crosslinkable functional group-containing compound, and a fluorine-containing compound containing a crosslinkable functional group-containing compound. Examples of commercially available products such as the crosslinkable functional group-containing fluorine-based compound include the trade names "Mega Fvck F-570", "Mega Fvck RS-55", "Mega Fvck RS-56", and "Mega Fvck". RS-72-K "," Mega Fvck RS-75 "," Mega Fvck RS-76-E "," Mega Fvck RS-76-NS "," Mega Fvck RS-78 "," Mega Fvck RS-90 " (Manufactured by DIC Co., Ltd.) and the like.

By using a low molecular weight polyol in combination with a silicone-based additive and / or a fluorine-based additive, it does not peel off more easily from the adherend, and even when stored for a long period of time in a harsh environment, it becomes heavy over time. It is possible to provide a surface protective film capable of suppressing peeling more sufficiently and having a sufficiently low contamination property on the surface of the adherend by being attached to the adherend.

When the low molecular weight polyol is used in combination with a silicone-based additive and / or a fluorine-based additive, the content of the low molecular weight polyol in the pressure-sensitive adhesive composition is preferably 0.01 part by weight with respect to 100 parts by weight of the base polymer. ~ 50 parts by weight, more preferably 0.05 parts by weight to 25 parts by weight, still more preferably 0.07 parts by weight to 30 parts by weight, still more preferably 0.1 parts by weight to 20 parts by weight. It is more preferably 0.3 parts by weight to 15 parts by weight, particularly preferably 0.5 parts by weight to 10 parts by weight, and most preferably 0.7 parts by weight to 7.0 parts by weight. When the low molecular weight polyol and the silicone-based additive and / or the fluorine-based additive are used in combination, if the content of the low molecular weight polyol in the pressure-sensitive adhesive composition is within the above range, the surface protective film of the present invention is adhered. It does not peel off more easily from the body, and even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be more sufficiently suppressed, and the adherence by sticking to the adherend. It can more exert the effect that the body surface is less polluted.

When a low molecular weight polyol is used in combination with a silicone-based additive and / or a fluorine-based additive, the content of the silicone-based additive and / or the fluorine-based additive in the pressure-sensitive adhesive composition is such that the content of the silicone-based additive and / or the fluorine-based additive is 100 parts by weight of the base polymer. The total amount of the system additive and the fluorine-based additive is preferably 0.001 part by weight to 50 parts by weight, more preferably 0.005 part by weight to 25 part by weight, and further preferably 0.01 part by weight. It is 10 parts by weight, more preferably 0.01 part by weight to 1 part by weight, further preferably 0.01 part by weight to 0.50 part by weight, and particularly preferably 0.01 part by weight to 0 part by weight. It is 30 parts by weight, most preferably 0.01 parts by weight to 0.10 parts by weight. When a low molecular weight polyol is used in combination with a silicone-based additive and / or a fluorine-based additive, the present invention indicates that the content of the silicone-based additive and / or the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range. The surface protective film of Fluorine does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, heavy peeling over time can be more sufficiently suppressed, and the adherend can be used. The effect that the contamination of the surface of the adherend is sufficiently lower by being attached to the substrate can be further exhibited. Specifically, it is as follows.

When the low molecular weight polyol and the silicone-based additive are used in combination but the fluorine-based additive is not used in combination, the content of the silicone-based additive in the pressure-sensitive adhesive composition is preferably 0.001 with respect to 100 parts by weight of the base polymer. It is 5 parts by weight to 50 parts by weight, more preferably 0.005 parts by weight to 25 parts by weight, further preferably 0.01 parts by weight to 10 parts by weight, and further preferably 0.01 parts by weight to 1 part by weight. Parts, more preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0.10 parts by weight. It is a part by weight. When the low molecular weight polyol and the silicone-based additive are used in combination but the fluorine-based additive is not used in combination, the surface protective film of the present invention can be used as long as the content of the silicone-based additive in the pressure-sensitive adhesive composition is within the above range. It does not peel off more easily from the adherend, and even if the initial peeling force after sticking to the adherend is large, it is possible to more sufficiently suppress heavy peeling over time, and by sticking to the adherend, the said. The effect that the contamination of the adherend surface is sufficiently low can be further exhibited.

When the low molecular weight polyol and the fluorine-based additive are used in combination but the silicone-based additive is not used in combination, the content of the fluorine-based additive in the pressure-sensitive adhesive composition is preferably 0.001 with respect to 100 parts by weight of the base polymer. It is 5 parts by weight to 50 parts by weight, more preferably 0.005 parts by weight to 25 parts by weight, further preferably 0.01 parts by weight to 10 parts by weight, and further preferably 0.01 parts by weight to 1 part by weight. Parts, more preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0.10 parts. It is a part by weight. When the low molecular weight polyol and the fluorine-based additive are used in combination but the silicone-based additive is not used in combination, the surface protective film of the present invention can be used as long as the content of the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range. It does not peel off more easily from the adherend, and even if the initial peeling force after sticking to the adherend is large, heavy peeling over time can be more sufficiently suppressed, and by sticking to the adherend, the said. The effect that the contamination of the adherend surface is sufficiently low can be further exhibited.

When the low molecular weight polyol, the silicone-based additive and the fluorine-based additive are used in combination, the total content ratio of the silicone-based additive and the fluorine-based additive to 100 parts by weight of the base polymer is preferably 0.001 part by weight to 50 parts by weight. Parts, more preferably 0.005 parts by weight to 25 parts by weight, still more preferably 0.01 parts by weight to 10 parts by weight, still more preferably 0.01 parts by weight to 1 part by weight, and further. It is preferably 0.01 parts by weight to 0.50 parts by weight, particularly preferably 0.01 parts by weight to 0.30 parts by weight, and most preferably 0.01 parts by weight to 0.10 parts by weight. When a low molecular weight polyol, a silicone-based additive, and a fluorine-based additive are used in combination, if the total content ratio of the silicone-based additive and the fluorine-based additive in the pressure-sensitive adhesive composition is within the above range, the surface of the present invention is used. The protective film does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, heavy peeling over time can be more sufficiently suppressed, and the protective film can be attached to the adherend. It is possible to exhibit the effect that the contamination of the surface of the adherend by attaching is sufficiently lower.

<A-2-5. Urethane resin>
The urethane prepolymer and the polyol as the base polymer can be combined with the polyfunctional isocyanate compound (B), respectively, and can be a component of the composition for forming the urethane-based resin. By adopting the above as a component of the composition for forming the urethane resin, the surface protective film of the present invention was not easily peeled off from the adherend and was attached to the adherend. Even if the initial peeling force is large, the heavy peeling over time can be sufficiently suppressed, and the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low can be further exhibited.

The composition for forming the urethane-based resin may contain any suitable other components as long as the effects of the present invention are not impaired. Examples of such components include resin components other than urethane-based resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and ultraviolet absorbers. Examples thereof include agents, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat-resistant stabilizers, polymerization inhibitors, lubricants, solvents, catalysts and the like.

The composition for forming the urethane-based resin preferably contains an antioxidant such as an antioxidant, an ultraviolet absorber, and a light stabilizer. Since the composition for forming the urethane resin contains a deterioration inhibitor, adhesive residue is generated on the adherend even if the adhesive layer to be formed is attached to the adherend and then stored in a heated state. It may be difficult to prevent adhesive residue. The deterioration inhibitor may be only one kind or two or more kinds. As the deterioration inhibitor, an antioxidant is particularly preferable.

Examples of the antioxidant include a radical chain inhibitor, a peroxide decomposing agent and the like.

Examples of the radical chain inhibitor include phenol-based antioxidants and amine-based antioxidants.

Examples of the peroxide decomposing agent include sulfur-based antioxidants and phosphorus-based antioxidants.

Examples of the phenol-based antioxidant include monophenol-based antioxidants, bisphenol-based antioxidants, and polymer-type phenol-based antioxidants.

Examples of the monophenolic antioxidant include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, and stear-β- ( 3,5-Di-t-butyl-4-hydroxyphenyl) propionate and the like can be mentioned.

Examples of the bisphenol-based antioxidant include 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2,2'-methylenebis (4-ethyl-6-t-butylphenol), and 4,4'. -Thiobis (3-methyl-6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), 3,9-bis [1,1-dimethyl-2- [β-( 3-t-Butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane and the like can be mentioned.

Examples of the high molecular weight phenolic antioxidant include 1,1,3-tris (2-methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4. 6-Tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane , Bis [3,3'-bis- (4'-hydroxy-3'-t-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3', 5'-di-t-butyl) -4'-Hydroxybenzyl) -S-triazine-2,4,6- (1H, 3H, 5H) trione, tocophenol and the like can be mentioned.

Examples of the sulfur-based antioxidant include dilauryl 3,3'-thiodipropionate, dimyristyl 3,3'-thiodipropionate, and distearyl 3,3'-thiodipropionate.

Examples of the phosphorus-based antioxidant include triphenylphosphine, diphenylisodecylphosphite, phenyldiisodecylphosphite and the like.

Examples of the ultraviolet absorber include benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, salicylic acid-based ultraviolet absorbers, oxalic acid anilide-based ultraviolet absorbers, cyanoacrylate-based ultraviolet absorbers, and triazine-based ultraviolet absorbers. Be done.

Examples of the benzophenone-based ultraviolet absorber include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, and 2,2'. -Dihydroxy-4-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy-5-benzoylphenyl) ) Examples include methane.

Examples of the benzotriazole-based ultraviolet absorber include 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2- ( 2'-Hydroxy-3', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2 -(2'-Hydroxy-3', 5'-di-tert-butylphenyl) 5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-tert-amylphenyl) benzotriazole, 2- (2'-Hydroxy-4'-octoxyphenyl) benzotriazole, 2- [2'-hydroxy-3'-(3'', 4'', 5'', 6'', -tetrahydrophthalimidemethyl ) -5'-Methylphenyl] benzotriazole, 2,2'methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole-2-yl) phenol], 2- (2'-Hydroxy-5'-metaacryloxyphenyl) -2H-benzotriazole and the like can be mentioned.

Examples of the salicylic acid-based ultraviolet absorber include phenylsalicylate, p-tert-butylphenylsalicylate, p-octylphenylsalicylate and the like.

Examples of the cyanoacrylate-based ultraviolet absorber include 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate and ethyl-2-cyano-3,3'-diphenylacrylate.

Examples of the light stabilizer include hindered amine-based light stabilizers and ultraviolet stabilizers.

Examples of the hindered amine-based light stabilizer include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, and methyl. -1,2,2,6,6-pentamethyl-4-piperidyl sebacate and the like can be mentioned.

Examples of the ultraviolet stabilizer include nickel bis (octylphenyl) sulfide, [2,2'-thiobis (4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-tert-. Examples thereof include butyl-4-hydroxybenzyl-phosphate monoethylate, nickel-dibutyldithiocarbamate, benzoate type quencher, nickel-dibutyldithiocarbamate and the like.

[A-2-5-a. Urethane-based resin formed from a composition containing a urethane prepolymer and a polyfunctional isocyanate compound (B)]
The urethane-based resin formed from the composition containing the urethane prepolymer and the polyfunctional isocyanate compound (B) is formed, for example, from the composition containing the polyurethane polyol as the urethane prepolymer and the polyfunctional isocyanate compound (B). Urethane-based resin can be mentioned.

The urethane prepolymer may be only one kind or two or more kinds.

The polyfunctional isocyanate compound (B) may be only one kind or two or more kinds.

As the polyfunctional isocyanate compound (B), any suitable polyfunctional isocyanate compound that can be used in the urethanization reaction can be adopted. Examples of such a polyfunctional isocyanate compound (B) include a polyfunctional aliphatic isocyanate compound, a polyfunctional alicyclic isocyanate, and a polyfunctional aromatic isocyanate compound.

Examples of the polyfunctional aliphatic isocyanate compound include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,3-butylenediocyanate, dodecamethylene diisocyanate, 2,4. Examples thereof include 4-trimethylhexamethylene diisocyanate.

Examples of the polyfunctional alicyclic isocyanate compound include 1,3-cyclopentene diisocyanate, 1,3-cyclohexanediisocyanate, 1,4-cyclohexanediisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, and hydrogenated xylylene diisocyanate. Examples thereof include hydrogenated tolylene diisocyanate and hydrogenated tetramethylxylylene diisocyanate.

Examples of the polyfunctional aromatic diisocyanate compound include phenylenediocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 2,2'-diphenylmethane diisocyanate, and 4,4'-diphenylmethane diisocyanate, 4 , 4'-toluene diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalenediocyanate, xylylene diisocyanate and the like.

Examples of the polyfunctional isocyanate compound (B) include a trimethylolpropane adduct compound of various polyfunctional isocyanate compounds as described above, a biuret compound reacted with water, and a trimer having an isocyanurate ring. Moreover, you may use these together.

The composition containing the urethane prepolymer and the polyfunctional isocyanate compound (B) may contain any suitable other components as long as the effects of the present invention are not impaired. Examples of such other components include resin components other than polyurethane resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and the like. Examples thereof include ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts and the like.

The method for forming the polyurethane resin from the composition containing the urethane prepolymer and the polyfunctional isocyanate compound (B) is arbitrary as long as it is a method for producing the polyurethane resin using the so-called "urethane prepolymer" as a raw material. Appropriate manufacturing method can be adopted.

The number average molecular weight Mn of the urethane prepolymer is preferably 3000 to 1000000.

The equivalent ratio of NCO group to OH group in the urethane prepolymer and the polyfunctional isocyanate compound (B) is preferably 5.0 or less, more preferably 0.01 to 4.75 as the NCO group / OH group. It is more preferably 0.02 to 4.5, particularly preferably 0.03 to 4.25, and most preferably 0.05 to 4.0. When the equivalent ratio of NCO group / OH group is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend is high. Even if it is large, it is possible to more sufficiently suppress heavy peeling over time, and it is possible to exhibit the effect that the contamination of the surface of the adherend by attaching it to the adherend is sufficiently low.

The content of the polyfunctional isocyanate compound (B) is preferably 0.01% by weight to 30% by weight, more preferably 0.05% by weight, based on the urethane prepolymer. It is ~ 25% by weight, more preferably 0.1% by weight to 20% by weight, particularly preferably 0.5% by weight to 17.5% by weight, and most preferably 1% by weight to 15% by weight. be. When the content ratio of the polyfunctional isocyanate compound (B) is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is initially peeled off after being attached to the adherend. Even if the force is large, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be exhibited.

[A-2-5-b. Urethane-based resin formed from a composition containing a polyol and a polyfunctional isocyanate compound (B)]
The urethane-based resin formed from the composition containing the polyol and the polyfunctional isocyanate compound (B) is specifically obtained by curing the composition containing the polyol and the polyfunctional isocyanate compound (B). It is a urethane resin that is used.

The polyol may be only one kind or two or more kinds.

The polyfunctional isocyanate compound (B) may be only one kind or two or more kinds.

As the polyfunctional isocyanate compound (B), those described above can be incorporated.

The equivalent ratio of NCO group to OH group in the polyol (A) and the polyfunctional isocyanate compound (B) is preferably 5.0 or less, more preferably 0.1 to 3.0, as the NCO group / OH group. It is more preferably 0.2 to 2.5, particularly preferably 0.3 to 2.25, and most preferably 0.5 to 2.0. When the equivalent ratio of NCO group / OH group is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and the initial peeling force after being attached to the adherend is high. Even if it is large, it is possible to more sufficiently suppress heavy peeling over time, and it is possible to further exhibit the effect that the contamination of the surface of the adherend by attaching it to the adherend is sufficiently low.

The content ratio of the polyfunctional isocyanate compound (B) is preferably 1.0% by weight to 30% by weight, more preferably 1.5% by weight to 27% by weight of the polyfunctional isocyanate compound (B) with respect to the polyol. It is% by weight, more preferably 2.0% by weight to 25% by weight, particularly preferably 2.3% by weight to 23% by weight, and most preferably 2.5% by weight to 20% by weight. When the content ratio of the polyfunctional isocyanate compound (B) is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend and is initially peeled off after being attached to the adherend. Even if the force is large, heavy peeling over time can be more sufficiently suppressed, and the effect that the contamination of the surface of the adherend by sticking to the adherend is sufficiently low can be exhibited.

Specifically, the polyurethane-based resin is preferably formed by curing a composition containing a polyol and a polyfunctional isocyanate compound (B). As a method for forming a urethane-based resin by curing a composition containing a polyol and a polyfunctional isocyanate compound (B), an effect of the present invention is not impaired, such as a urethanization reaction method using bulk polymerization or solution polymerization. Any suitable method may be adopted in the range.

A catalyst is preferably used to cure the composition containing the polyol and the polyfunctional isocyanate compound (B). Examples of such a catalyst include organometallic compounds and tertiary amine compounds.

Examples of the organic metal-based compound include iron-based compounds, tin-based compounds, titanium-based compounds, zirconium-based compounds, lead-based compounds, cobalt-based compounds, and zinc-based compounds. Among these, iron-based compounds and tin-based compounds are preferable in terms of reaction rate and pot life of the pressure-sensitive adhesive layer.

Examples of the iron-based compound include iron acetylacetonate and iron 2-ethylhexanoate.

Examples of the tin-based compound include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin maleate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin sulfide, tributyltin methoxyde, tributyltin acetate, and triethyltinethoxydo. Examples thereof include tributyl tin ethoxydo, dioctyl tin oxide, dioctyl tin dilaurate, tributyl tin chloride, tributyl tin trichloroacetate, tin 2-ethylhexanoate and the like.

Examples of the titanium-based compound include dibutyl titanium dichloride, tetrabutyl titanate, butoxytitanium trichloride and the like.

Examples of the zirconium-based compound include zirconium naphthenate and zirconium acetylacetonate.

Examples of the lead-based compound include lead oleate, lead 2-ethylhexanoate, lead benzoate, lead naphthenate and the like.

Examples of the cobalt-based compound include cobalt 2-ethylhexanoate and cobalt benzoate.

Examples of the zinc-based compound include zinc naphthenate and zinc 2-ethylhexanoate.

Examples of the tertiary amine compound include triethylamine, triethylenediamine, 1,8-diazabisik mouth- (5,4,0) -undecene-7 and the like.

The catalyst may be only one kind or two or more kinds. Further, the catalyst and the cross-linking retarder may be used in combination. The amount of the catalyst is preferably 0.005% by weight to 1.00% by weight, more preferably 0.01% by weight to 0.75% by weight, still more preferably 0.01% by weight, based on the polyol. % To 0.50% by weight, particularly preferably 0.01% by weight to 0.20% by weight. When the amount of the catalyst is within the above range, the surface protective film of the present invention does not peel off more easily from the adherend, and even if the initial peeling force after being attached to the adherend is large, the peeling force over time is large. It is possible to more sufficiently suppress heavy peeling, and it is possible to further exhibit the effect that the contamination of the surface of the adherend by attaching to the adherend is sufficiently low.

The composition containing the polyol and the polyfunctional isocyanate compound (B) may contain any suitable other components as long as the effects of the present invention are not impaired. Examples of such other components include resin components other than polyurethane resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and the like. Examples thereof include ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts and the like.

<A-2-6. Other ingredients>
The pressure-sensitive adhesive composition may contain any suitable other ingredients as long as the effects of the present invention are not impaired. Examples of such other components include other resin components, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, and ultraviolet absorbers. , Antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, polymerization inhibitors, lubricants, solvents, catalysts and the like.

The pressure-sensitive adhesive composition may contain an ionic liquid containing a fluoroorganic anion. When the pressure-sensitive adhesive composition contains an ionic liquid containing a fluoroorganic anion, it is possible to provide a pressure-sensitive adhesive composition having excellent antistatic properties. Such an ionic liquid may be only one kind or two or more kinds.

In the present invention, the ionic liquid means a molten salt (ionic compound) that exhibits a liquid at 25 ° C.

As the ionic liquid, any suitable ionic liquid can be adopted as long as it is an ionic liquid containing a fluoroorganic anion, as long as the effects of the present invention are not impaired. Such an ionic liquid is preferably an ionic liquid composed of a fluoroorganic anion and an onium cation. By adopting an ionic liquid composed of a fluoroorganic anion and an onium cation as the ionic liquid, it is possible to provide a pressure-sensitive adhesive composition having extremely excellent antistatic properties.

As the onium cation that can form an ionic liquid, any suitable onium cation can be adopted as long as the effect of the present invention is not impaired. The onium cation is preferably at least one selected from a nitrogen-containing onium cation, a sulfur-containing onium cation, and a phosphorus-containing onium cation. By selecting these onium cations, it is possible to provide a pressure-sensitive adhesive composition having extremely excellent antistatic properties.

As the fluoroorganic anion that can constitute an ionic liquid, any suitable fluoroorganic anion can be adopted as long as the effects of the present invention are not impaired. Such fluoroorganic anions may be completely fluorinated (perfluoro) or partially fluorinated.

Examples of such fluoroorganic anions include fluorinated arylsulfonates, perfluoroalkanesulfonates, bis (fluorosulfonyl) imides, bis (perfluoroalkanesulfonyl) imides, cyanoperfluoroalkanesulfonylamides, and bis (cyano). Perfluoroalkanesulfonyl methide, cyano-bis- (perfluoroalkanesulfonyl) methide, tris (perfluoroalkanesulfonyl) methide, trifluoroacetate, perfluoroalkanelate, tris (perfluoroalkanesulfonyl) methide, (perfluoroalkane sulfonyl) Sulfonyl) Trifluoroacetamide and the like.

Commercially available ionic liquids may be used, but they can also be synthesized as described below. The method for synthesizing an ionic liquid is not particularly limited as long as the desired ionic liquid can be obtained, but in general, the document "Ionic Liquid-Forefront and Future of Development-" (CMC Publishing Co., Ltd.) The halide method, hydroxide method, acid ester method, complex formation method, neutralization method and the like as described in (Issued) are used.

The blending amount of the ionic liquid cannot be unconditionally defined because it varies depending on the compatibility between the polymer used and the ionic liquid, but in general, it is preferably 0.001 with respect to 100 parts by weight of the base polymer. It is 50 parts by weight to 50 parts by weight, more preferably 0.01 parts by weight to 40 parts by weight, further preferably 0.01 parts by weight to 30 parts by weight, and particularly preferably 0.01 parts by weight to 20 parts by weight. Parts, most preferably 0.01 parts by weight to 10 parts by weight. By adjusting the blending amount of the ionic liquid within the above range, it is possible to provide a pressure-sensitive adhesive composition having excellent antistatic properties. If the blending amount of the ionic liquid is less than 0.01 parts by weight, sufficient antistatic properties may not be obtained. If the blending amount of the ionic liquid exceeds 50 parts by weight, contamination of the adherend tends to increase.

The pressure-sensitive adhesive composition may contain a modified silicone oil as long as the effects of the present invention are not impaired. By including the modified silicone oil in the pressure-sensitive adhesive composition, the effect of antistatic properties can be exhibited. In particular, when used in combination with an ionic liquid, the effect of antistatic properties can be exhibited even more effectively.

When the pressure-sensitive adhesive composition contains a modified silicone oil, the content thereof is preferably 0.001 part by weight to 50 parts by weight, more preferably 0.005 part by weight to 40 parts by weight, based on 100 parts by weight of the base polymer. It is parts by weight, more preferably 0.007 parts by weight to 30 parts by weight, particularly preferably 0.008 parts by weight to 20 parts by weight, and most preferably 0.01 parts by weight to 10 parts by weight. By adjusting the content ratio of the modified silicone oil within the above range, the effect of the antistatic property can be more effectively exhibited.

As the modified silicone oil, any suitable modified silicone oil may be adopted as long as the effects of the present invention are not impaired. Examples of such modified silicone oils include modified silicone oils available from Shin-Etsu Chemical Co., Ltd.

The modified silicone oil is preferably a polyether-modified silicone oil. By adopting a polyether-modified silicone oil, the effect of antistatic properties can be exhibited even more effectively.

Examples of the polyether-modified silicone oil include side-chain type polyether-modified silicone oil and both-terminal type polyether-modified silicone oil. Among these, the double-ended type polyether-modified silicone oil is preferable in that the effect of the antistatic property can be sufficiently and more effectively exhibited.

≪≪B. Uses ≫≫
The surface protective film of the present invention does not easily peel off from the adherend, and even if the initial peeling force after being attached to the adherend is large, heavy peeling over time can be sufficiently suppressed, and the adherend can be sufficiently peeled off. It is possible to exhibit the effect that the contamination of the surface of the adherend is sufficiently low by attaching to. Therefore, it can be suitably used for surface protection of optical members and electronic members. The optical member of the present invention is the one to which the surface protective film of the present invention is attached. The electronic member of the present invention is the one to which the surface protective film of the present invention is attached.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. The tests and evaluation methods in the examples and the like are as follows. In addition, when it is described as "part", it means "part by weight" unless there is a special note, and when it is described as "%", it means "% by weight" unless there is a special note.

<Peeling force A from the glass plate (after leaving at a temperature of 23 ° C for 30 minutes)>
The adhesive layer side of the surface protective film (width 25 mm x length 140 mm) from which the separator has been peeled off is attached to a glass plate (soda lime glass, manufactured by Matsunami Glass Industry Co., Ltd.) with a 2 kg hand roller once and again, and the environment is 23 ° C. It was left at a temperature for 30 minutes.
The evaluation sample obtained as described above was measured with a tensile tester. As the tensile tester, a trade name "Autograph AG-Xplus HS 6000 mm / min high-speed model (AG-50NX plus)" manufactured by Shimadzu Corporation was used. The evaluation sample was set in the tensile tester, and the tensile test was started. Specifically, the load when the surface protective film was peeled from the glass plate was measured, and the average load at that time was defined as the peeling force A of the surface protective film from the glass plate. The conditions of the tensile test were a test environment temperature: 23 ° C., a peeling angle: 180 degrees, and a peeling speed (tensile speed): 300 mm / min.

<Peeling force B from the glass plate (after leaving at a temperature of 100 ° C for 2 days)>
The adhesive layer side of the surface protective film (width 25 mm x length 140 mm) from which the separator has been peeled off is attached to a glass plate (soda lime glass, manufactured by Matsunami Glass Industry Co., Ltd.) with a 2 kg hand roller once and again, and the temperature is 100 ° C. It was left in the environment for 2 days.
The evaluation sample obtained as described above was measured with a tensile tester. As the tensile tester, a trade name "Autograph AG-Xplus HS 6000 mm / min high-speed model (AG-50NX plus)" manufactured by Shimadzu Corporation was used. The evaluation sample was set in the tensile tester, and the tensile test was started. Specifically, the load when the surface protective film was peeled from the glass plate was measured, and the average load at that time was defined as the peeling force B of the surface protective film from the glass plate. The conditions of the tensile test were a test environment temperature: 23 ° C., a peeling angle: 180 degrees, and a peeling speed (tensile speed): 300 mm / min.

<Peeling force C from the glass plate (after leaving at a temperature of 23 ° C for 7 days)>
The adhesive layer side of the surface protective film (width 25 mm x length 140 mm) from which the separator was peeled off was attached to a glass plate (soda lime glass, manufactured by Matsunami Glass Industry Co., Ltd.) with a 2 kg hand roller once and again, and the temperature was 23 ° C. It was left in the environment for 7 days.
The evaluation sample obtained as described above was measured with a tensile tester. As the tensile tester, a trade name "Autograph AG-Xplus HS 6000 mm / min high-speed model (AG-50NX plus)" manufactured by Shimadzu Corporation was used. The evaluation sample was set in the tensile tester, and the tensile test was started. Specifically, the load when the surface protective film was peeled from the glass plate was measured, and the average load at that time was defined as the peeling force C of the surface protective film from the glass plate. The conditions of the tensile test were a test environment temperature: 23 ° C., a peeling angle: 180 degrees, and a peeling speed (tensile speed): 300 mm / min.

<Residual adhesion to glass plate at 23 ° C>
The adhesive layer side of the surface protection film from which the separator was peeled off was attached to the entire surface of a glass plate (made by Matsunami Glass, 1.35 mm x 10 cm x 10 cm) with a 1 reciprocating 2 kg hand roller, and the temperature was 23 ° C and the humidity was 55% RH. After storing for 24 hours in the above atmosphere, the surface protective film was peeled off at a rate of 0.3 m / min to prepare a treated glass plate.
Subsequently, a 19 mm wide No. 1 cut into a length of 150 mm was formed on the surface of the treated glass plate from which the surface protective film had been peeled off. A 31B tape (manufactured by Nitto Denko Corporation, substrate thickness: 25 μm) was attached by one reciprocating 2 kg hand roller in an atmosphere of a temperature of 23 ° C. and a humidity of 55% RH. After curing for 30 minutes in an atmosphere with a temperature of 23 ° C and a humidity of 55% RH, a tensile tester (trade name "Autograph AG-Xplus HS 6000 mm / min high-speed model (AG-50NX plus)" manufactured by Shimadzu Corporation) The peeling angle was 180 degrees and the peeling speed was 300 mm / min, and the adhesive strength a was measured.
Separately, even for a glass plate (manufactured by Matsunami Glass, 1.35 mm × 10 cm × 10 cm) that has not been subjected to the above-mentioned surface protective film bonding and peeling treatment, a 19 mm wide No. The adhesive strength b of the 31B tape was measured.
The residual adhesion ratio was calculated by the following formula.
Residual adhesion rate (%) = (adhesive force a / adhesive force b) x 100
This residual adhesive ratio is an index of how much the component of the pressure-sensitive adhesive layer of the surface protective film is transferred to the surface of the adherend and contaminated with respect to the adherend. The higher the residual adhesion ratio value, the less likely the surface of the adherend to be contaminated with the components of the pressure-sensitive adhesive layer. It is a surface protection film that is easily contaminated with.

<Storage modulus X1, X2, Y1, Y2>
(Sample preparation method)
The pressure-sensitive adhesive composition was applied to the peel-treated surface of a polyester film (trade name: MRF, manufactured by Mitsubishi Chemical Corporation) having a thickness of 38 μm, one side of which was peel-treated with silicone, with a fountain roll so that the thickness after drying was 50 μm. It was cured and dried under the conditions of a drying temperature of 130 ° C. and a drying time of 3 minutes. In this way, the pressure-sensitive adhesive layer was produced on the substrate. Next, a polyester film (trade name: MRF, manufactured by Mitsubishi Chemical Corporation) having a thickness of 38 μm, one side of which was peeled off with silicone, was applied to the surface of the pressure-sensitive adhesive layer so that the peeled-off surface of the film was on the pressure-sensitive adhesive layer side. And covered. In this way, a surface protective film for evaluation was produced. As for the surface protective film for evaluation, the one in the environment of temperature 23 ° C. was used for measuring the storage elastic modulus X1 and X2, and the one in the environment of temperature 23 ° C. after being left at the temperature of 80 ° C. for 7 days was used for the storage elastic modulus. It was used for the measurement of Y1 and Y2.
(Measuring method)
Only the pressure-sensitive adhesive layer was taken out from the obtained surface protective film for evaluation, laminated to a thickness of about 2 mm, punched to φ7.9 mm, and columnar pellets were prepared and used as a measurement sample. The measurement sample was fixed to a jig of a φ7.9 mm parallel plate, and the storage elastic modulus G'was calculated by a dynamic viscoelasticity measuring device (ARES manufactured by Leometrics). The measurement conditions are as follows. In addition, "a E + b" described in the table ^{means "a × 10 b} " as is generally well known.
Measurement: Shear mode Temperature range: -70 ° C to 150 ° C
Temperature rise rate: 5 ° C / min
Frequency: 1Hz

[Production Example 1]: Production of urethane prepolymer solution A 1L round bottom separable flask, separable cover, liquid separation funnel, thermometer, nitrogen introduction tube, Liebig condenser, vacuum seal, stirring rod, stirring blade are equipped. 150 g of polypropylene glycol (product name "Sannicks PP-2000", Mn = 2000, manufactured by Sanyo Kasei Kogyo Co., Ltd.), polyester polyol (product name "Kurare polyol P-2010", Mn = 2000,) in the experimental device for polymerization. Add 150 g of Kuraray), 110 g of toluene (manufactured by Toso) as a solvent, and 0.041 g of dibutyl tin dilaurate (IV) (manufactured by Wako Pure Chemical Industries, Ltd.) as a catalyst, and stir at room temperature. Nitrogen substitution was carried out for 1 hour. After that, 33.5 g of hexamethylene diisocyanate (product name "HDI", manufactured by Tosoh Corporation) was added while stirring under the inflow of nitrogen, and the solution temperature in the experimental device was controlled to 90 ± 2 ° C. in a water bath. After holding for 4 hours, 74.9 g of polypropylene glycol (product name "GP1000", Mn = 1000, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was added, and the solution temperature in the experimental device was 90 ± 2 ° C. in a water bath. After holding for 2 hours while controlling the concentration, add 25.4 g of hexamethylene diisocyanate (product name "HDI", manufactured by Tosoh Corporation), and the solution temperature in the experimental device becomes 90 ± 2 ° C. in a water bath. The mixture was kept for 2 hours while being controlled in such a manner to obtain a urethane prepolymer solution A. In addition, during the polymerization, toluene was appropriately added dropwise in order to control the temperature during the polymerization and prevent the decrease in agitation due to the increase in viscosity. The total amount of toluene dropped was 320 g. The solid content concentration of the urethane prepolymer solution A was 50% by weight.

[Example 1]
As shown in Table 1, 100 parts by weight of the obtained urethane prepolymer solution A in terms of polymer solid content and 20 parts of an isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) in terms of solid content. 0.0 parts by weight and heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF) in terms of solid content 4.0 parts by weight and polyol (trade name "Sannicks GP250", Mn = 250, Sanyo Kasei Kogyo Add 3.0 parts by weight of solids equivalent (manufactured by DIC Corporation) and 0.05 parts by weight of fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) in terms of solids, and the whole solid The pressure-sensitive adhesive composition (1) was obtained by diluting with ethyl acetate so that the content was 45% by weight. The obtained pressure-sensitive adhesive composition (1) is applied to a base material made of polyester resin (trade name "T100-75S", thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying is 75 μm, and dried. It was cured and dried under the conditions of a temperature of 130 ° C. and a drying time of 3 minutes. In this way, a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (1) was produced on the substrate. Next, the surface of the obtained pressure-sensitive adhesive layer was treated with silicone on a release sheet (trade name "MRF25", thickness 25 μm, manufactured by Mitsubishi Chemical Corporation) made of a polyester resin having a thickness of 25 μm, one of which was treated with silicone. The surfaces were bonded together to obtain a surface protective film (1). The obtained surface protective film (1) was aged at room temperature for 7 days and evaluated. The release sheet was peeled off immediately before the evaluation. The results are shown in Table 2.

[Example 2]
As shown in Table 1, the same procedure as in Example 1 was carried out except that the amount of the heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF) was changed to 6.0 parts by weight in terms of solid content, and the adhesive was adhered. A pressure-sensitive adhesive layer made of the agent composition (2) was prepared, and a surface protective film (2) was obtained. The results are shown in Table 2.

[Example 3]
As shown in Table 1, the same procedure as in Example 1 was carried out except that the amount of the heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF) was changed to 8.0 parts by weight in terms of solid content, and the adhesive was adhered. A pressure-sensitive adhesive layer made of the agent composition (3) was prepared, and a surface protective film (3) was obtained. The results are shown in Table 2.

[Example 4]
As shown in Table 1, the same procedure as in Example 1 was carried out except that the amount of the heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF) was changed to 10.0 parts by weight in terms of solid content, and the adhesive was adhered. A pressure-sensitive adhesive layer made of the agent composition (4) was prepared, and a surface protective film (4) was obtained. The results are shown in Table 2.

[Example 5]
As shown in Table 1, the same procedure as in Example 1 was carried out except that the amount of the heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF) was changed to 15.0 parts by weight in terms of solid content, and the adhesive was adhered. A pressure-sensitive adhesive layer made of the agent composition (5) was prepared, and a surface protective film (5) was obtained. The results are shown in Table 2.

[Example 6]
As shown in Table 1, instead of using a heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF), a heat-resistant stabilizer (trade name "Irganox 1135", manufactured by BASF) is used in terms of solid content. The same procedure as in Example 1 was carried out except that it was used as 0 part by weight, a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (6) was prepared, and a surface protective film (6) was obtained. The results are shown in Table 2.

[Example 7]
As shown in Table 1, instead of using a heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF), a heat-resistant stabilizer (trade name "Irganox 1135", manufactured by BASF) is used in terms of solid content. The same procedure as in Example 1 was carried out except that it was used as 0 part by weight, a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (7) was prepared, and a surface protective film (7) was obtained. The results are shown in Table 2.

[Example 8]
As shown in Table 1, instead of using a heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF), a heat-resistant stabilizer (trade name "Irganox 1135", manufactured by BASF) is used in terms of solid content. The same procedure as in Example 1 was carried out except that it was used as 0 part by weight, a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (8) was prepared, and a surface protective film (8) was obtained. The results are shown in Table 2.

[Example 9]
As shown in Table 1, instead of using a heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF), a heat-resistant stabilizer (trade name "Irganox 1135", manufactured by BASF) is used in terms of solid content. The same procedure as in Example 1 was carried out except that it was used as 0 part by weight, a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (9) was prepared, and a surface protective film (9) was obtained. The results are shown in Table 2.

[Example 10]
As shown in Table 1, instead of using a heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF), a heat-resistant stabilizer (trade name "Irganox 1135", manufactured by BASF) is used in terms of solid content. The same procedure as in Example 1 was carried out except that it was used as 0 part by weight, a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (10) was prepared, and a surface protective film (10) was obtained. The results are shown in Table 2.

[Example 11]
As shown in Table 1, the same procedure as in Example 1 was carried out except that a heat-resistant stabilizer (trade name “TINUVIN765”, manufactured by BASF) was additionally used in an amount of 4.0 parts by weight in terms of solid content. A pressure-sensitive adhesive layer made of (11) was prepared, and a surface protective film (11) was obtained. The results are shown in Table 2.

[Example 12]
As shown in Table 1, instead of using a heat-resistant stabilizer (trade name "Irganox 1010", manufactured by BASF), a heat-resistant stabilizer (trade name "Irganox 1135", manufactured by BASF) is used in terms of solid content. The same procedure as in Example 1 was carried out except that a heat-resistant stabilizer (trade name "TINUVIN765", manufactured by BASF) was additionally used in an amount of 0 parts by weight and an additional 4.0 parts by weight in terms of solid content was used. A pressure-sensitive adhesive layer made of 12) was prepared to obtain a surface protective film (12). The results are shown in Table 2.

[Example 13]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 18.8 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF, a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (manufactured by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as 2.0 parts by weight in terms of solid content, and fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) is not used. Except for the above, the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (13), and a surface protective film (13) was obtained. The results are shown in Table 2.

[Example 14]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 26.0 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF, a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (manufactured by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as 3.0 parts by weight in terms of solid content, and fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) is not used. Except for the above, the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (14), and a surface protective film (14) was obtained. The results are shown in Table 2.

[Example 15]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 33.2 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF, a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (manufactured by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as 4.0 parts by weight in terms of solid content, and fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) is not used. Except for the above, the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (15), and a surface protective film (15) was obtained. The results are shown in Table 2.

[Example 16]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 40.8 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF, a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (manufactured by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemical Co., Ltd.) is used as 5.0 parts by weight in terms of solid content, and fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) is not used. Except for the above, the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (16), and a surface protective film (16) was obtained. The results are shown in Table 2.

[Example 17]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 18.8 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF), a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , Made by BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (made by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemicals Co., Ltd.) is used as 2.0 parts by weight in terms of solid content, and the amount of fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) used. Was changed to 0.075 parts by weight in terms of solid content, and the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (17) to obtain a surface protective film (17). The results are shown in Table 2.

[Example 18]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 26.0 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF), a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , Made by BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (made by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemicals Co., Ltd.) is used as 3.0 parts by weight in terms of solid content, and the amount of fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) used. Was changed to 0.075 parts by weight in terms of solid content, and the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (18) to obtain a surface protective film (18). The results are shown in Table 2.

[Example 19]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 33.2 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF), a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , Made by BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (made by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemicals Co., Ltd.) is used as 4.0 parts by weight in terms of solid content, and the amount of fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) used. Was changed to 0.075 parts by weight in terms of solid content, and the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (19) to obtain a surface protective film (19). The results are shown in Table 2.

[Example 20]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 40.6 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF), a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name" TINUVIN765 "" is used. , Made by BASF) with an additional 4.0 parts by weight in terms of solid content, and instead of using a polyol (trade name "Sannicks GP250", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.), trimethylolpropane (made by Sanyo Kasei Kogyo Co., Ltd.) Product name "TMP", Mn = 134, manufactured by Mitsubishi Gas Chemicals Co., Ltd.) is used as 5.0 parts by weight in terms of solid content, and the amount of fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) used. Was changed to 0.075 parts by weight in terms of solid content, and the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (20) to obtain a surface protective film (20). The results are shown in Table 2.

[Example 21]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 16.0 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. Instead of using Knox 1010 ", manufactured by BASF), a heat-resistant stabilizer (trade name" Irganox 1135 ", manufactured by BASF) is used as 8.0 parts by weight in terms of solid content, and a polyol (trade name" Sanniks GP250 ") is used. , Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to 1.5 parts by weight in terms of solid content, and instead of using a fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation) A hydroxyl group-containing silicone (trade name "X-22-4015", manufactured by Shin-Etsu Chemical Industry Co., Ltd.) was used as 0.05 parts by weight in terms of solid content, and the same procedure as in Example 1 was carried out to prepare a pressure-sensitive adhesive composition (21). ) Was prepared, and a surface protective film (21) was obtained. The results are shown in Table 2.

[Comparative Example 1]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Industry Co., Ltd.) was changed to 6.5 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. The same procedure as in Example 1 was carried out except that the amount was changed to 1.0 part by weight in terms of minutes, to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C1), and a surface protective film (C1) was obtained. The results are shown in Table 2.

[Comparative Example 2]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Industry Co., Ltd.) was changed to 13.2 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. The same procedure as in Example 1 was carried out except that the amount was changed to 3.0 parts by weight in terms of minutes, to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C2), and a surface protective film (C2) was obtained. The results are shown in Table 2.

[Comparative Example 3]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Industry Co., Ltd.) was changed to 20.0 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. The same procedure as in Example 1 was carried out except that the amount was changed to 5.0 parts by weight in terms of minutes, to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C3), and a surface protective film (C3) was obtained. The results are shown in Table 2.

[Comparative Example 4]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 6.5 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. Same as Example 1 except that the fatty acid ester (trade name "Saracos 816", manufactured by Nisshin Oillio Co., Ltd.) was changed to 1.0 part by weight in terms of minutes and 1.0 part by weight was added in terms of solid content. To prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C4), a surface protective film (C4) was obtained. The results are shown in Table 2.

[Comparative Example 5]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 13.2 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. Same as Example 1 except that the fatty acid ester (trade name "Saracos 816", manufactured by Nisshin Oillio Co., Ltd.) was changed to 3.0 parts by weight in terms of minutes and 1.0 part by weight was added in terms of solids. To prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C5), a surface protective film (C5) was obtained. The results are shown in Table 2.

[Comparative Example 6]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 20.0 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. Same as Example 1 except that the amount is changed to 5.0 parts by weight in terms of minutes and 1.0 part by weight of fatty acid ester (trade name "Saracos 816", manufactured by Nisshin Oillio Co., Ltd.) is added in terms of solids. To prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C6), a surface protective film (C6) was obtained. The results are shown in Table 2.

[Comparative Example 7]
As shown in Table 1, the amount of isocyanate-based cross-linking agent (trade name "Coronate HL", manufactured by Nippon Polyurethane Co., Ltd.) was changed to 16.0 parts by weight in terms of solid content, and the heat-resistant stabilizer (trade name "Irga") was changed. The amount of Knox 1010 ", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of polyol (trade name" Sanniks GP250 ", Mn = 250, manufactured by Sanyo Kasei Kogyo Co., Ltd.) was changed to solid. Change to 1.5 parts by weight in terms of minutes, and instead of using a fluorine-containing polymer (trade name "F-571", manufactured by DIC Corporation), a hydroxyl group-containing silicone (trade name "X-22-4015", Shinetsu) The same procedure as in Example 1 was carried out except that (manufactured by Kagaku Kogyo Co., Ltd.) was used as 0.05 parts by weight in terms of solid content, to prepare a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition (C7), and a surface protective film (a surface protective film (C7)) was prepared. C7) was obtained. The results are shown in Table 2.

[Examples 22 to 42]
For each of the surface protective films (1) to (21) obtained in Examples 1 to 21, the separator is peeled off, and the pressure-sensitive adhesive layer side is a polarizing plate which is an optical member (manufactured by Nitto Denko KK, trade name " TEG1465DUHC ") was attached to obtain an optical member to which a surface protective film was attached.

[Examples 43 to 63]
For each of the surface protective films (1) to (21) obtained in Examples 1 to 21, the separator is peeled off, and the pressure-sensitive adhesive layer side is a conductive film (manufactured by Nitto Denko KK, trade name) which is an electronic member. It was attached to "Electrica V270L-TFMP") to obtain an electronic member to which a surface protective film was attached.

The surface protective film of the present invention can be used for any suitable application. Preferably, the surface protective film of the present invention is preferably used in the field of optical members and electronic members.

1 Base material layer 2 Adhesive layer 10 Surface protective film

Claims (11)

A surface protective film having an adhesive layer,
After the pressure-sensitive adhesive layer of the surface protective film is attached to a glass plate and left at a temperature of 23 ° C. for 30 minutes, the surface protective film is peeled off from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm / min at a temperature of 23 ° C. When the peeling force at the time of peeling is the peeling force A, the peeling force A is 0.005N / 25mm to 0.50N / 25mm.
The pressure-sensitive adhesive layer of the surface protective film was attached to a glass plate and left at a temperature of 100 ° C. for 2 days, and then the surface protective film was peeled from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm / min at a temperature of 23 ° C. When the peeling force at the time of peeling is the peeling force B, the peeling force with time increase rate P1 calculated by (peeling force B / peeling force A) × 100 is 200% or less.
Surface protective film. When the storage elastic modulus of the pressure-sensitive adhesive layer at 23 ° C. is defined as the storage elastic modulus X1, and the storage elastic modulus at a temperature of 23 ° C. after the surface protective film is left at a temperature of 80 ° C. for 7 days is defined as the storage elastic modulus Y1. The surface protective film according to claim 1, wherein the storage elastic modulus change rate Q1 calculated by (storage elastic modulus Y1 / storage elastic modulus X1) × 100 is 150% or less. After the pressure-sensitive adhesive layer of the surface protective film was attached to a glass plate and left at a temperature of 23 ° C. for 7 days, the surface protective film was peeled off from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm / min at a temperature of 23 ° C. The invention according to claim 1 or 2, wherein when the peeling force at the time of peeling is the peeling force C, the peeling force with time increase rate P2 calculated by (peeling force C / peeling force A) × 100 is 160% or less. Surface protection film. The surface protective film according to any one of claims 1 to 3, wherein the residual adhesion rate to the glass plate at 23 ° C. is 50% or more. The surface protective film according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer is formed from the pressure-sensitive adhesive composition, and the pressure-sensitive adhesive composition contains a heat-resistant stabilizer. The surface protective film according to claim 5, wherein the pressure-sensitive adhesive composition comprises a base polymer, a low molecular weight polyol, a silicone-based additive and / or a fluorine-based additive. The surface protective film according to claim 6, wherein the silicone-based additive is at least one selected from a siloxane bond-containing compound, a hydroxyl group-containing silicone-based compound, and a crosslinkable functional group-containing silicone-based compound. The surface protective film according to claim 6, wherein the fluorine-based additive is at least one selected from a fluorine-containing compound, a hydroxyl group-containing fluorine-based compound, and a crosslinkable functional group-containing fluorine-based compound. The surface protective film according to any one of claims 6 to 8, wherein the base polymer is at least one selected from urethane prepolymers, polyols, acrylic resins, rubber resins, and silicone resins. An optical member to which the surface protective film according to any one of claims 1 to 9 is attached. An electronic member to which the surface protective film according to any one of claims 1 to 9 is attached.

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