CN113302049A - Surface protective film - Google Patents

Abstract

Provided is a surface-protecting film which is not easily peeled from an adherend, can sufficiently suppress the occurrence of re-peeling over time even when stored for a long period of time in a severe environment, and has sufficiently low staining properties on the surface of the adherend due to adhesion to the adherend. A surface protection film of the present invention has an adhesive layer, wherein the adhesive layer of the surface protection film is bonded to a glass plate and left at 23 ℃ for 30 minutes, the surface protection film is peeled from the glass plate at a peeling angle of 180 DEG and a peeling speed of 300 mm/minute at 23 ℃, the peeling force A is 0.005N/25mm to 0.50N/25mm when the peeling force is defined as peeling force A, the adhesive layer of the surface protection film is bonded to the glass plate and left at 100 ℃ for 2 days, the surface protection film is peeled from the glass plate at a peeling angle of 180 DEG and a peeling speed of 300 mm/minute at 23 ℃, and the rate of increase P1 with time of the peeling force calculated as (peeling force B/peeling force A) × 100 when the peeling force is defined as peeling force B is 200% or less.

Description

Surface protective film

Technical Field

The present invention relates to a surface protective film.

Background

In the manufacturing process of an optical member or an electronic member, a surface protective film is generally attached to an exposed surface of the optical member or the electronic member in order to prevent damage to the surface of the optical member or the electronic member during processing, assembly, inspection, transportation, and the like. Such a surface protection film is peeled off from an optical member or an electronic member when surface protection is not required (patent document 1).

In the optical member and the electronic member to which such a surface protective film is attached, when the surface protective film is to be peeled as described above, it is important to be able to smoothly peel only at the interface between the surface protective film and the optical member or the electronic member.

However, when the optical member or the electronic member includes a member which is easily broken, such as a thin glass or a barrier film, and the surface protective film to be attached is peeled, the member which is easily broken may be broken by a peeling force even when a conventional surface protective film having a light peeling property is used.

Therefore, a surface protection film having a lighter peelability, i.e., an ultra-light peelability, than a conventional surface protection film having a light peelability has been reported (patent document 2).

However, the prior art has the following problems: for example, when stored under severe conditions for a long period of time, the adhesive strength increases with time, and re-peeling occurs.

In order to suppress the re-exfoliation, there is also a method of adding an excessive amount of an additive as reported in patent document 2. However, such a method has the following problems: after the surface protection film is peeled off, the degree of contamination of the surface of the adherend is large, and if the surface protection film is to be attached again, the surface protection film is difficult to attach due to the contamination of the surface of the adherend.

As described above, for example, in the production process of optical members and electronic members, a surface protective film to be attached to an exposed surface in order to prevent damage to the surface during processing, assembly, inspection, transportation, and the like is required to have: in particular, even when stored for a long period of time in a severe environment, the removability over time can be sufficiently suppressed, and the staining property of the adherend surface can be sufficiently reduced.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-

Patent document 2: japanese patent laid-open publication No. 2017-160422

Disclosure of Invention

Problems to be solved by the invention

The present invention addresses the problem of providing a surface-protecting film which is not easily peeled off from an adherend, can sufficiently suppress the occurrence of re-peeling over time even when stored for a long period of time in a severe environment, and has sufficiently low staining of the adherend surface due to adhesion to the adherend.

Means for solving the problems

The surface protective film of the present invention has an adhesive layer,

the adhesive layer of the surface protective film is bonded to a glass plate and left at 23 ℃ for 30 minutes, and then the surface protective film is peeled from the glass plate at 23 ℃ at a peeling angle of 180 degrees and a peeling speed of 300 mm/minute, and the peeling force A is 0.005N/25mm to 0.50N/25mm when the peeling force is defined as peeling force A,

the pressure-sensitive adhesive layer of the surface protective film is bonded to a glass plate and left at 100 ℃ for 2 days, and then the surface protective film is peeled from the glass plate at 23 ℃ at a peeling angle of 180 degrees and a peeling speed of 300 mm/min, and when the peeling force at this peeling is defined as a peeling force B, the rate of increase P1 with time of the peeling force calculated as (peeling force B/peeling force A) × 100 is 200% or less.

In one embodiment, when the storage modulus of the pressure-sensitive adhesive layer at 23 ℃ is X1 and the storage modulus of the surface protection film at 23 ℃ after being left at 80 ℃ for 7 days is Y1, the storage modulus change rate Q1 calculated as (storage modulus Y1/storage modulus X1) × 100 is 150% or less.

In one embodiment, the adhesive layer of the surface protective film is bonded to a glass plate and left at 23 ℃ for 7 days, and then the surface protective film is peeled from the glass plate at 23 ℃ at a peeling angle of 180 degrees and a peeling speed of 300 mm/min, and when the peeling force at this time is taken as the peeling force C, the peeling force increase rate P2 with time calculated as (peeling force C/peeling force a) × 100 is 160% or less.

In one embodiment, the surface protection film of the present invention has a residual adhesion rate to a glass plate at 23 ℃ of 50% or more.

In one embodiment, the adhesive constituting the adhesive layer is formed of an adhesive composition containing a heat-resistant stabilizer.

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

In one embodiment, the silicone additive is at least 1 selected from the group consisting of a silicone bond-containing compound, a hydroxyl group-containing silicone compound, and a crosslinkable functional group-containing silicone compound.

In one embodiment, the fluorine-containing additive is at least 1 selected from the group consisting of a fluorine-containing compound, a hydroxyl group-containing fluorine-containing compound, and a crosslinkable functional group-containing fluorine-containing compound.

In one embodiment, the base polymer is at least 1 selected from the group consisting of urethane prepolymer, polyol, acrylic resin, rubber resin, and silicone resin.

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

The surface protective film of the present invention is attached to the electronic component of the present invention.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the following surface protection film can be provided: the adhesive is not easily peeled from an adherend, can sufficiently suppress re-peeling over time even if the initial peeling force after the adhesive is attached to the adherend is large, and has sufficiently low staining properties on the surface of the adherend due to the attachment to the adherend.

Drawings

Fig. 1 is a schematic cross-sectional view of a surface protective film according to an embodiment of the present invention.

Detailed Description

Surface protective film (A)

The surface protection film of the present invention has an adhesive layer. The surface protection film of the present invention may be provided with any other suitable member as long as it has an adhesive layer, within a range not impairing the effects of the present invention. Typically, the surface protection 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 protection film 10 includes a base layer 1 and a pressure-sensitive adhesive layer 2. In fig. 1, a base material layer 1 and an adhesive layer 2 are directly laminated.

In fig. 1, the surface of the pressure-sensitive adhesive layer 2 opposite to the base material layer 1 may be provided with any suitable release liner (also referred to as a release sheet or separator) (not shown) for the purpose of protection before use. Examples of the release liner include release liners obtained by treating the surface of a substrate (liner substrate) such as paper or a plastic film with silicone; and release liners in which the surface of a substrate (liner substrate) such as paper or plastic film is laminated with a polyolefin resin. Examples of the plastic film as the spacer base material include a polyethylene film, a polypropylene film, a polybutylene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, a polybutylene terephthalate film, a polyurethane film, an ethylene-vinyl acetate copolymer film, and the like. The plastic film as the base material of the gasket is preferably a polyethylene film.

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

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

The surface protective film of the present invention is obtained by bonding the adhesive layer of the surface protective film to a glass plate and leaving the surface protective film at a temperature of 23 ℃ for 30 minutes, and then peeling the surface protective film from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm/minute at a temperature of 23 ℃, wherein the peeling force is preferably 0.005N/25mm to 0.50N/25mm, more preferably 0.007N/25mm to 0.40N/25mm, further preferably 0.010N/25mm to 0.30N/25mm, further preferably 0.012N/25mm to 0.20N/25mm, further preferably 0.015N/25mm to 0.10N/25mm, particularly preferably 0.012N/25mm to 0.050N/25mm, and most preferably 0.010N/25mm to 0.040N/25mm, when the peeling force is defined as the peeling force A. When the peeling force a is within the above range, the surface protective film of the present invention can be less likely to be easily peeled from an adherend, and typically, the surface protective film of the present invention attached to the exposed surface of an optical member or an electronic member can be less likely to be peeled in the production process of the optical member or the electronic member. The details of the measurement of the peeling force a will be described later.

The surface protection film of the present invention is obtained by bonding the adhesive layer of the surface protection film to a glass plate and leaving the surface protection film at a temperature of 100 ℃ for 2 days, and then peeling the surface protection film from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm/minute at a temperature of 23 ℃, wherein the peeling force B is preferably 0.010N/25mm to 1.0N/25mm, more preferably 0.010N/25mm to 0.50N/25mm, further preferably 0.010N/25mm to 0.20N/25mm, particularly preferably 0.010N/25mm to 0.10N/25mm, and most preferably 0.010N/25mm to 0.070N/25mm, when the peeling force is defined as peeling force B. When the peeling force B is within the above range, the surface protection film of the present invention can more sufficiently suppress re-peeling over time even when stored under severe environment for a long period of time. The details of the measurement of the peeling force B will be described later.

The rate of increase over time of the peeling force P1 calculated as (peeling force B/peeling force a) × 100 in the peeling force a and the peeling force B of the surface protection film of the present invention is preferably 200% or less, more preferably 190% or less, still more preferably 180% or less, particularly preferably 170% or less, and most preferably 160% or less. The lower limit of the peeling force increase rate P1 with time is preferably smaller, but actually, it is preferably 80% or more. When the increase rate P1 of the peeling force with time is within the above range, the surface protective film of the present invention is less likely to peel from an adherend, and even when stored for a long period of time in a severe environment, re-peeling with time can be sufficiently suppressed.

The surface protection film of the present invention is obtained by bonding the adhesive layer of the surface protection film to a glass plate and leaving the surface protection film at a peeling angle of 180 degrees and a peeling speed of 300 mm/min at 23 ℃ for 7 days, and then peeling the surface protection film from the glass plate at a peeling angle of 180 degrees and a peeling speed of 300 mm/min at 23 ℃, wherein the peeling force is preferably 0.001N/25mm to 0.50N/25mm, more preferably 0.001N/25mm to 0.30N/25mm, further preferably 0.001N/25mm to 0.20N/25mm, further preferably 0.003N/25mm to 0.10N/25mm, further preferably 0.005N/25mm to 0.075N/25mm, particularly preferably 0.008N/25mm to 0.050N/25mm, and most preferably 0.010N/25mm to 0.040N/25 mm. When the peeling force C is within the above range, the surface protection film of the present invention can more sufficiently suppress re-peeling over time even when stored under severe environment for a long period of time. The details of the measurement of the peeling force C will be described later.

The rate of increase over time of the peeling force P2 calculated as (peeling force C/peeling force a) × 100 in the peeling force a and the peeling force C of the surface protection film of the present invention is preferably 160% or less, more preferably 155% or less, still more preferably 150% or less, particularly preferably 145% or less, and most preferably 140% or less. The lower limit of the peeling force increase rate P2 with time is preferably smaller, but actually, it is preferably 80% or more. When the increase rate P2 of the peeling force with time is within the above range, the surface protecting film of the present invention is less likely to peel from an adherend, and even when stored for a long period of time in a severe environment, re-peeling with time can be more sufficiently suppressed.

In the surface-protecting film of the present invention, the storage modulus X1 of the adhesive layer at 23 ℃ is preferably 1.0X 10⁵Pa～1.0×10⁷Pa, more preferably 3.0X 10⁵Pa～7.0×10⁶Pa, more preferably 5.0X 10⁵Pa～5.0×10⁶Pa, particularly preferably 6.0X 10⁵Pa～4.0×10⁶Pa, most preferably 7.0X 10⁵Pa～3.0×10⁶Pa. When the storage modulus X1 is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low. The details of the measurement of the storage modulus X1 will be described later.

In the surface protective film of the present invention, the surface protective film is heated at a temperature of 80 deg.CThe storage modulus Y1 at 23 ℃ after standing at 7 days is preferably 1.0X 10⁵Pa～1.0×10⁷Pa, more preferably 2.0X 10⁵Pa～7.0×10⁶Pa, more preferably 3.0X 10⁵Pa～5.0×10⁶Pa, particularly preferably 5.0X 10⁵Pa～3.0×10⁶Pa, most preferably 6.0X 10⁵Pa～2.0×10⁶Pa. When the storage modulus Y1 is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low. The details of the measurement of the storage modulus Y1 will be described later.

The storage modulus change rate Q1 of the surface protection film of the present invention, which is calculated as (storage modulus Y1/storage modulus X1) × 100, is preferably 150% or less, more preferably 145% or less, still more preferably 140% or less, particularly preferably 135% or less, and most preferably 130% or less in the storage modulus X1 and the storage modulus Y1. The lower limit of the storage modulus change rate Q1 is preferably smaller, but is actually preferably 80% or more. When the storage modulus change rate Q1 is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

In the surface-protecting film of the present invention, the storage modulus X2 of the adhesive layer at 100 ℃ is preferably 1.0X 10⁵Pa～7.0×10⁶Pa, more preferably 3.0X 10⁵Pa～5.0×10⁶Pa, more preferably 5.0X 10⁵Pa～3.0×10⁶Pa, particularly preferably 6.0X 10⁵Pa～2.0×10⁶Pa, most preferably 6.5X 10⁵Pa～1.5×10⁶Pa. When the storage modulus X2 is within the above range, the surface protective film of the present invention can further exhibit the following effects: is less prone to self-adhesionEven if the initial peeling force after the attachment to the adherend is large, the peeling can be suppressed more sufficiently over time, and the staining of the adherend surface caused by the attachment to the adherend is sufficiently low. The details of the measurement of the storage modulus X2 will be described later.

In the surface-protecting film of the present invention, the storage modulus Y2 at 100 ℃ after the surface-protecting film is left at 80 ℃ for 7 days is preferably 1.0X 10⁵Pa～1.0×10⁷Pa, more preferably 2.0X 10⁵Pa～7.0×10⁶Pa, more preferably 3.0X 10⁵Pa～5.0×10⁶Pa, particularly preferably 5.0X 10⁵Pa～2.0×10⁶Pa, most preferably 5.5X 10⁵Pa～1.0×10⁶Pa. When the storage modulus Y2 is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low. The details of the measurement of the storage modulus Y2 will be described later.

The storage modulus change rate Q2 of the surface protection film of the present invention, which is calculated as (storage modulus Y2/storage modulus X2) × 100, is preferably 150% or less, more preferably 145% or less, still more preferably 140% or less, particularly preferably 135% or less, and most preferably 130% or less in the storage modulus X2 and the storage modulus Y2. The lower limit of the storage modulus change rate Q2 is preferably smaller, but is actually preferably 80% or more. When the storage modulus change rate Q2 is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The surface protection film of the present invention has a residual adhesion ratio of preferably 50% or more, more preferably 60% to 100%, even more preferably 70% to 100%, particularly preferably 80% to 100%, and most preferably 85% to 100%. When the residual adhesion ratio is within the above range, the surface protective film of the present invention can exhibit the following effects: staining of the adherend surface by attachment to the adherend is sufficiently low. The details of the measurement of the residual adhesion ratio will be described later.

The surface protective film of the present invention can be produced by any suitable method. Such a production method can be performed, for example, by any suitable production method described below:

(1) method for coating solution or hot melt of material for forming adhesive layer on base layer,

(2) A method of applying a solution or hot melt of a material for forming an adhesive layer on a separator and transferring the formed adhesive layer to a base material layer,

(3) A method of extruding a material for forming the adhesive layer to form a coating on the base material layer,

(4) A method of extruding the substrate layer and the adhesive layer in two or more layers,

(5) A method of single-layer laminating an adhesive layer on a substrate layer or a method of double-layer laminating an adhesive layer together with a laminating layer,

(6) A method of laminating an adhesive layer and a substrate layer-forming material such as a film or a laminate layer in two or more layers.

As a method of coating, for example, a roll coating method, a comma coating method, a die coating method, a reverse coating method, a screen printing method, a gravure coating method, or the like can be used.

A-1. substrate layer

The base material layer may be 1 layer only, or may be 2 or more layers. The substrate layer may be stretched.

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

For the purpose of forming a roll which is easy to unwind, for example, a surface of the substrate layer to which the pressure-sensitive adhesive layer is not attached may be subjected to a release treatment by adding a fatty acid amide, a polyethyleneimine, a long-chain alkyl additive, or the like to the substrate layer, or may be provided with a coating layer formed of any suitable release agent such as a silicone-based, long-chain alkyl-based, or fluorine-based release agent.

As the material of the base layer, any suitable material can be used depending on the application. Examples thereof include plastics, paper, metal films, and nonwoven fabrics. Preferably plastic. That is, the base material layer is preferably a plastic film. The base layer may be made of 1 kind of material, or may be made of 2 or more kinds of materials. For example, it may be made of 2 or more kinds of plastics.

Examples of the plastic include polyester resins, polyamide resins, and polyolefin resins. Examples of the polyester 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 homopolypropylene; propylene copolymers such as block, random and graft copolymers containing an ethylene component as a copolymer component; reactor TPO; low density, high density, linear low density, ultra low density, and the like ethylene-based polymers; ethylene copolymers such as ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, ethylene-methyl acrylate copolymers, ethylene-ethyl acrylate copolymers, ethylene-butyl acrylate copolymers, ethylene-methacrylic acid copolymers, and ethylene-methyl methacrylate copolymers; and the like.

The base layer may contain any suitable additive as required. Examples of additives that can be contained in the base layer include antioxidants, ultraviolet absorbers, light stabilizers, antistatic agents, fillers, and pigments. The kind, number, and amount of the additives that can be contained in the base 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 preferred examples of the additives include antioxidants, ultraviolet absorbers, light stabilizers, and fillers.

As the antioxidant, any suitable antioxidant can be used. Examples of such antioxidants include phenol antioxidants, phosphorus processing heat stabilizers, lactone processing heat stabilizers, sulfur heat stabilizers, and phenol/phosphorus antioxidants. The content ratio of the antioxidant is preferably 1% by weight or less, more preferably 0.5% by weight or less, and further preferably 0.01% by weight to 0.2% by weight, based on the base resin of the base material layer (when the base material layer is a mixture, the mixture is the base resin).

As the ultraviolet absorber, any suitable ultraviolet absorber can be used. Examples of such an ultraviolet absorber include benzotriazole-based ultraviolet absorbers, triazine-based ultraviolet absorbers, and benzophenone-based ultraviolet absorbers. The content ratio of the ultraviolet absorber is preferably 2% by weight or less, more preferably 1% by weight or less, and further preferably 0.01% by weight to 0.5% by weight, based on the base resin forming the base layer (when the base layer is a mixture, the mixture is the base resin).

As the light stabilizer, any suitable light stabilizer can be used. Examples of such a light stabilizer include a hindered amine light stabilizer and a benzoate light stabilizer. The content ratio of the light stabilizer is preferably 2% by weight or less, more preferably 1% by weight or less, and still more preferably 0.01% by weight to 0.5% by weight, based on the base resin forming the base layer (when the base layer is a mixture, the mixture is the base resin).

As the filler, any suitable filler can be used. Examples of such a filler include inorganic fillers. Specific examples of the inorganic filler include carbon black, titanium oxide, and zinc oxide. The content of the filler is preferably 20% by weight or less, more preferably 10% by weight or less, and still more preferably 0.01% by weight to 10% by weight, based on the base resin forming the base layer (when the base layer is a mixture, the mixture is the base resin).

Further, for the purpose of imparting antistatic properties, preferred examples of the additive include surfactants, inorganic salts, inorganic, low molecular weight and high molecular weight antistatic agents such as polyols, metal compounds and carbon. In particular, from the viewpoint of contamination and maintenance of adhesiveness, a high molecular weight antistatic agent and carbon are preferable.

Adhesive layer A-2

The adhesive layer may be composed of an adhesive. The adhesive may be formed from an adhesive composition.

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

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

The adhesive composition preferably comprises a heat stabilizer. By including the heat-resistant stabilizer in the adhesive composition, the following surface-protecting film can be provided: the adhesive sheet is excellent in heat resistance, is less likely to be peeled from an adherend, can more sufficiently suppress the occurrence of re-peeling with time even if the initial peeling force after the adhesive sheet is attached to the adherend is large, and is sufficiently low in staining of the surface of the adherend due to the attachment to the adherend. This is presumably because: the heat stabilizer can exhibit an effect that has not been achieved conventionally by the presence of other components (for example, a low molecular weight polyol, a silicone-based additive, and/or a fluorine-based additive) that can be contained in the adhesive composition.

The heat stabilizer may be contained in the adhesive composition in an amount of only 1 kind, or 2 or more kinds.

As the heat stabilizer, any suitable heat stabilizer may be used as long as the effects of the present invention are not impaired. Typical examples of such heat stabilizers include antioxidants, light stabilizers, heat stabilizers, and ultraviolet absorbers. From the viewpoint of further exhibiting the effects of the present invention, an antioxidant and a light stabilizer are preferable as the heat stabilizer. In addition, an antioxidant and a light stabilizer may be used in combination.

Examples of the antioxidant include a radical chain inhibitor and a peroxide decomposer.

Examples of the radical chain inhibitor include a phenol-based antioxidant and an amine-based antioxidant.

Examples of the peroxide decomposer include a sulfur-based antioxidant, a phosphorus-based antioxidant and the like.

Examples of the phenol antioxidant include monophenol antioxidants, bisphenol antioxidants, and high-molecular phenol antioxidants.

Examples of the monophenol-based antioxidant include 2, 6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2, 6-di-t-butyl-4-ethylphenol, and stearyl β - (3, 5-di-t-butyl-4-hydroxyphenyl) propionate.

Examples of the bisphenol-based antioxidant include 2,2 '-methylenebis (4-methyl-6-tert-butylphenol), 2' -methylenebis (4-ethyl-6-tert-butylphenol), 4 '-thiobis (3-methyl-6-tert-butylphenol), 4' -butylidenebis (3-methyl-6-tert-butylphenol), 3, 9-bis [1, 1-dimethyl-2- [ β - (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ]2,4,8, 10-tetraoxaspiro [5,5] undecane, and the like.

Examples of the high-molecular-weight phenol-based 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) butyrate ] diol ester, 1,3, 5-tris (3 ', 5 ' -di-t-butyl-4 ' -hydroxybenzyl) -s-triazine-2, 4,6- (1H,3H,5H) triketones, tocopherols, and the like.

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 triphenyl phosphite, diphenylisodecyl phosphite, and phenyldiisodecyl phosphite.

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

Examples of the ultraviolet stabilizer include nickel bis (octylphenyl) sulfide, [2, 2' -thiobis (4-tert-octylphenol) ] -n-butylamine nickel, 3, 5-di-tert-butyl-4-hydroxybenzylphosphonate monoethanol nickel complex, nickel dibutyldithiocarbamate, a benzoate-type quencher, and nickel dibutyldithiocarbamate.

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

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

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

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' -octyloxyphenyl) benzotriazole, 2-bis (t-butylphenyl) benzotriazole, and the like, 2- [2 '-hydroxy-3' - (3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5 '-methylphenyl ] benzotriazole, 2' methylenebis [4- (1,1,3, 3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol ], [2(2 '-hydroxy-5' -methacryloxyphenyl) -2H-benzotriazole, and the like.

Examples of the salicylic acid-based ultraviolet absorber include phenyl salicylate, p-tert-butyl phenyl salicylate, and p-octyl phenyl salicylate.

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

The content of the heat stabilizer in the adhesive composition is preferably 1.0 to 30 wt%, more preferably 1.5 to 27.5 wt%, even more preferably 2.0 to 25 wt%, even more preferably 2.5 to 22.5 wt%, even more preferably 2.75 to 20 wt%, even more preferably 3.0 to 15 wt%, even more preferably 3.5 to 12 wt%, particularly preferably 4.0 to 10 wt%, and most preferably 4.5 to 10 wt% based on 100 parts by weight of the base polymer. By adjusting the content ratio of the heat stabilizer in the adhesive composition to 100 parts by weight of the base polymer within the above range, the following surface protection film can be provided: the adhesive sheet is excellent in heat resistance, is less likely to be peeled from an adherend, can more sufficiently suppress the occurrence of re-peeling with time even if the initial peeling force after the adhesive sheet is attached to the adherend is large, and is sufficiently low in staining of the surface of the adherend due to the attachment to the adherend.

The heat stabilizer is preferably a liquid heat stabilizer. By making the heat stabilizer liquid, the dispersibility of the heat stabilizer in the adhesive composition is improved as compared with, for example, a solid heat stabilizer, and thus the following surface protection film can be provided: the adhesive sheet is more excellent in heat resistance, is less likely to be peeled from an adherend, can more sufficiently suppress the occurrence of re-peeling with time even if the initial peeling force after the adhesive sheet is attached to the adherend is large, and is further sufficiently low in staining of the surface of the adherend due to the attachment to the adherend.

The heat stabilizer is preferably a heat stabilizer having a hindered phenol structure. When the heat stabilizer having a hindered phenol structure is contained as the heat stabilizer, the content of the heat stabilizer having a hindered phenol structure in the adhesive composition is preferably 1.0 to 30 wt%, more preferably 1.5 to 27.5 wt%, further preferably 2.0 to 25 wt%, further preferably 2.5 to 22.5 wt%, further preferably 2.75 to 20 wt%, further preferably 3.0 to 15 wt%, further preferably 3.5 to 12 wt%, particularly preferably 4.0 to 10 wt%, and most preferably 4.5 to 10 wt%, based on 100 parts by weight of the base polymer. By adjusting the content ratio of the heat stabilizer having a hindered phenol structure in the adhesive composition to the above range with respect to 100 parts by weight of the base polymer, the following surface protection film can be provided: the adhesive sheet is excellent in heat resistance, is less likely to be peeled from an adherend, can more sufficiently suppress the occurrence of re-peeling with time even if the initial peeling force after the adhesive sheet is attached to the adherend is large, and is sufficiently low in staining of the surface of the adherend due to the attachment to the adherend.

As the heat stabilizer having a hindered phenol structure, any suitable heat stabilizer may be used as long as it has a hindered phenol structure in which a group having a large steric hindrance, such as a tert-butyl group, is bonded to at least one of adjacent carbon atoms of carbon atoms in an aromatic ring to which an OH group of phenol is bonded. By using a specific heat stabilizer such as a heat stabilizer having a hindered phenol structure, the following surface protective film can be provided: the adhesive sheet is excellent in heat resistance, is less likely to be peeled from an adherend, can more sufficiently suppress the occurrence of re-peeling with time even if the initial peeling force after the adhesive sheet is attached to the adherend is large, and is sufficiently low in staining of the surface of the adherend due to the attachment to the adherend.

Specific examples of the heat stabilizer having a hindered phenol structure include dibutylhydroxytoluene (BHT); trade name "IRGANOX 1010" (manufactured by BASF), trade name "IRGANOX 1010 FF" (manufactured by BASF), trade name "IRGANOX 1035 FF" (manufactured by BASF), trade name "IRGANOX 1076 FD" (manufactured by BASF), trade name "IRGANOX 1076 DWJ" (manufactured by BASF), trade name "IRGANOX 1098" (manufactured by BASF), trade name "IRGANOX 1135" (manufactured by BASF), trade name "IRGANOX 1330" (manufactured by BASF), trade name "IRGANOX 1726" (manufactured by BASF), trade name "IRGANOX 142nox 5 1425 WL" (manufactured by BASF), trade name "IRGANOX 1520L" (manufactured by BASF), trade name "IRGANOX 245 FF" (manufactured by BASF 259 "(manufactured by BASF), trade name" IRGANOX3114 "(manufactured by BASF), trade name" IRGANOX565 "(manufactured by BASF), and hindered phenol antioxidants (manufactured by BASF 295); benzotriazole-based ultraviolet absorbers such as "TINUVIN P" (manufactured by BASF), "TINUVIN PFL" (manufactured by BASF), "TINUVIN 234" (manufactured by BASF), "TINUVIN 326 FL" (manufactured by BASF), "TINUVIN 328" (manufactured by BASF), "TINUVIN 329" (manufactured by BASF) and "TINUVIN 329 FL" (manufactured by BASF); liquid ultraviolet absorbers such as "TINUVIN 213" (manufactured by BASF) and "TINUVIN 571" (manufactured by BASF); triazine-based ultraviolet absorbers such as "TINUVIN 1577 ED" (manufactured by BASF); benzoate-based ultraviolet absorbers under the trade name "TINUVIN 120" (manufactured by BASF); hindered amine light stabilizers such as "TINUVIN 144" (manufactured by BASF) and "TINUVIN 765" (manufactured by BASF); and the like.

As described above, the heat stabilizer is preferably a liquid heat stabilizer, and is preferably a heat stabilizer having a hindered phenol structure. Therefore, a heat stabilizer having a hindered phenol structure and being in a liquid state under the trade name "IRGANOX 1135" (manufactured by BASF) or the like is more preferable.

The adhesive composition preferably comprises a base polymer.

The adhesive composition preferably comprises a low molecular weight polyol.

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

More preferably, the adhesive composition comprises a base polymer and a low molecular weight polyol. By making the adhesive composition contain a base polymer and a low-molecular-weight polyol, the surface-protecting film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The adhesive composition further preferably contains a base polymer, a low molecular weight polyol, and a silicone-based additive and/or a fluorine-based additive. By making the adhesive composition contain a base polymer, a low-molecular-weight polyol, and a silicone-based additive and/or a fluorine-based additive, the surface protection film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

In a preferred embodiment of the present invention, when a low-molecular-weight polyol and a silicone-based additive and/or a fluorine-based additive are used in combination, a surface-protecting film which can further exhibit the following effects can be provided: it is less likely to peel off from an adherend, and even if the initial peeling force after attachment to an adherend is large, re-peeling over time can be more sufficiently suppressed, and staining of the adherend surface caused by attachment to an adherend is sufficiently low.

The content ratio of the base polymer and the low molecular weight polyol to the total amount of the silicone additive and the fluorine additive in the adhesive composition is preferably 50 to 100 wt%, more preferably 60 to 100 wt%, further preferably 70 to 100 wt%, particularly preferably 75 to 100 wt%, and most preferably 80 to 100 wt%. When the total content ratio of the base polymer, the silicone additive, and the fluorine additive in the adhesive composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is not easily peeled from an adherend, can sufficiently suppress re-peeling over time even if the initial peeling force after the adhesive sheet is attached to the adherend is large, and has sufficiently low staining of the adherend surface caused by the attachment to the adherend.

The content of the low-molecular-weight polyol in the adhesive composition is preferably 0.01 to 50 parts by weight, more preferably 0.05 to 25 parts by weight, even more preferably 0.07 to 30 parts by weight, even more preferably 0.1 to 20 parts by weight, even more preferably 0.3 to 15 parts by weight, particularly preferably 0.5 to 10 parts by weight, and most preferably 0.7 to 7.0 parts by weight, based on 100 parts by weight of the base polymer. When the content of the low-molecular-weight polyol in the adhesive composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The content of the silicone additive and/or the fluorine additive in the pressure-sensitive adhesive composition is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, further preferably 0.01 to 10 parts by weight, further preferably 0.01 to 1 part by weight, further preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer, which is the total amount of the silicone additive and the fluorine additive. When the content of the silicone-based additive and/or the fluorine-based additive in the adhesive composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

That is, when the silicone additive is contained in the pressure-sensitive adhesive composition but the fluorine additive is not contained, the content ratio of the silicone additive to 100 parts by weight of the base polymer is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, still more preferably 0.01 to 10 parts by weight, yet more preferably 0.01 to 1 part by weight, yet more preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight. When the content of the silicone additive in the adhesive composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

When the pressure-sensitive adhesive composition does not contain a silicone additive but contains a fluorine additive, the content of the fluorine additive is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, still more preferably 0.01 to 10 parts by weight, yet more preferably 0.01 to 1 part by weight, yet more preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer. When the content of the fluorine-based additive in the adhesive composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

When both the organosilicon additive and the fluorine additive are contained in the adhesive composition, the total content of the organosilicon additive and the fluorine additive is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, further preferably 0.01 to 10 parts by weight, further preferably 0.01 to 1 part by weight, further preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer. When the total content of the silicone additive and the fluorine additive in the binder composition is within the above range, the surface protection film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The silicone additive and/or the fluorine additive preferably contains a hydroxyl group-containing fluorine compound and/or a hydroxyl group-containing silicone compound as an essential component in order to further exhibit the effects of the present invention. That is, preferred embodiments of the silicone-based additive and/or the fluorine-based additive are: (1) an embodiment in which the fluorine-containing compound containing a hydroxyl group is required to be contained and the silicone-containing compound containing a hydroxyl group is not contained, (2) an embodiment in which the fluorine-containing compound containing a hydroxyl group is required to be contained and the fluorine-containing compound containing a hydroxyl group is not contained, (3) an embodiment in which both the fluorine-containing compound containing a hydroxyl group and the silicone-containing compound containing a hydroxyl group are required to be contained. In the case of the above-mentioned embodiment (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 to 100% by weight, more preferably 70 to 100% by weight, even more preferably 90 to 100% by weight, particularly preferably 95 to 100% by weight, and most preferably substantially 100% by weight, from the viewpoint of further exhibiting the effects of the present invention. In the case of the above-mentioned embodiment (2), the content ratio of the hydroxyl group-containing silicone compound in the total amount of the silicone additive and the fluorine additive is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, even more preferably 90 to 100% by weight, particularly preferably 95 to 100% by weight, and most preferably substantially 100% by weight, from the viewpoint of further exhibiting the effects of the present invention. In the case of the above-mentioned embodiment (3), the total content ratio of 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 is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, even more preferably 90 to 100% by weight, particularly preferably 95 to 100% by weight, and most preferably substantially 100% by weight, in view of further exhibiting the effects of the present invention.

< A-2-1. base Polymer >

The base polymer is preferably at least 1 selected from urethane prepolymer, polyol, acrylic resin, rubber resin, and silicone resin. When the base polymer is at least 1 selected from the group consisting of urethane prepolymer, polyol, acrylic resin, rubber resin, and silicone resin, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

[ A-2-1-a. urethane prepolymer ]

The urethane prepolymer is preferably a polyurethane polyol, and more preferably a polyurethane polyol obtained by reacting the polyester polyol (a1) or the polyether polyol (a2) with the organic polyisocyanate compound (a3) either alone or as a mixture of (a1) and (a2) in the presence or absence of 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 diol component. Examples of the acid component include terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid, and trimellitic acid. Examples of the diol component include ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1, 6-hexanediol, 3-methyl-1, 5-pentanediol, 3' -dimethylolheptane, polyoxyethylene glycol, polyoxypropylene glycol, 1, 4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin as a polyol component, trimethylolpropane, pentaerythritol, and the like. Examples of the polyester polyol (a1) include polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, poly (. beta. -methyl-. gamma. -valerolactone) and polycaprolactone.

The molecular weight of the polyester polyol (a1) may be from a low molecular weight to a high molecular weight. The molecular weight of the polyester polyol (a1) is preferably 100 to 100000 in number average molecular weight Mn. When the number average molecular weight Mn is less than 100, the reactivity may be high and gelation may be easily caused. If the number average molecular weight Mn exceeds 100000, 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 to 90 mol% in the polyol constituting the polyurethane polyol.

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

The polyether polyol (a2) may have any molecular weight from a low molecular weight to a high molecular weight. The polyether polyol (a2) preferably has a number average molecular weight Mn of 100 to 100000. When the number average molecular weight Mn is less than 100, the reactivity may be high and gelation may be easily caused. If the number average molecular weight Mn exceeds 100000, 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 to 90 mol% in the polyol constituting the polyurethane polyol.

The polyether polyol (a2) may be used in combination by partially replacing it with, if necessary, a polyhydric alcohol such as ethylene glycol, 1, 4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane, pentaerythritol, or a polyhydric amine such as ethylenediamine, N-aminoethylethanolamine, isophoronediamine, xylylenediamine, or the like.

The polyether polyol (a2) may be a 2-functional polyether polyol alone, or a polyether polyol having a number average molecular weight Mn of 100 to 100000 and at least 3 hydroxyl groups in1 molecule may be partially or entirely used. When a polyether polyol having a number average molecular weight Mn of 100 to 100000 and at least 3 hydroxyl groups in1 molecule is used as a part or all of the polyether polyol (a2), the balance between the adhesive strength and the removability can be improved. When the number average molecular weight Mn of such polyether polyol is less than 100, the reactivity may be high and gelation may be easily caused. In addition, when the number average molecular weight Mn of such polyether polyol exceeds 100000, the reactivity may be lowered and the cohesive force of the polyurethane polyol itself may be lowered. The number average molecular weight Mn of such polyether polyol is more preferably 100 to 10000.

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

Examples of the aromatic polyisocyanate include 1, 3-phenylene diisocyanate, 4 ' -diphenyl diisocyanate, 1, 4-phenylene diisocyanate, 4 ' -diphenylmethane diisocyanate, 2, 4-toluene diisocyanate, 2, 6-toluene diisocyanate, 4 ' -toluidine diisocyanate, 2,4, 6-triisocyanate toluene, 1,3, 5-triisocyanate benzene, dianisidine diisocyanate, 4 ' -diphenyl ether diisocyanate, and 4,4 ', 4 ″ -triphenylmethane triisocyanate.

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

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

Examples of the alicyclic polyisocyanate include 3-isocyanatomethyl-3, 5, 5-trimethylcyclohexyl isocyanate, 1, 3-cyclopentane diisocyanate, 1, 3-cyclohexane diisocyanate, 1, 4-cyclohexane diisocyanate, methyl-2, 6-cyclohexane diisocyanate, 4' -methylenebis (cyclohexyl isocyanate), 1, 4-bis (isocyanatomethyl) cyclohexane, and 1, 4-bis (isocyanatomethyl) cyclohexane.

As the organic polyisocyanate compound (a3), trimethylolpropane adduct, biuret formed by reaction with water, trimer having an isocyanurate ring, and 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, and 1, 8-diazabicyclo (5,4,0) -undec-7-ene (DBU).

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

Examples of the tin-based compound include dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (DBTDL), dibutyltin diacetate, dibutyltin sulfide, tributyltin oxide, tributyltin acetate, triethyltin acetate, tributyltin acetate, dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate.

Examples of the non-tin compound include titanium compounds such as dibutyltitanium dichloride, tetrabutyl titanate, butoxytitanium trichloride, etc.; lead compounds such as lead oleate, lead 2-ethylhexoate, lead benzoate, and lead naphthenate; iron compounds such as iron 2-ethylhexanoate and iron acetylacetonate; cobalt compounds such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc compounds such as zinc naphthenate and zinc 2-ethylhexanoate; zirconium compounds such as zirconium naphthenate; and the like.

When a catalyst is used for obtaining a polyurethane polyol, in a system in which 2 kinds of polyols, i.e., a polyester polyol and a polyether polyol, are present, there is a problem that gelation and turbidity of a reaction solution are likely to occur in a system in which a catalyst is used alone due to a difference in reactivity. Therefore, these problems can be solved by using 2 kinds of catalysts when obtaining the polyurethane polyol, so that it becomes easy to control the reaction rate, the selectivity of the catalyst, and the like. Examples of the combination of 2 kinds of catalysts include tertiary amine/organic metal type, tin type/non-tin type, and tin type/tin type, preferably tin type/tin type, and more preferably a combination of dibutyl tin dilaurate and 2-ethyl tin hexanoate. The compounding ratio thereof is preferably less than 1, more preferably 0.2 to 0.6 in terms of weight ratio of tin 2-ethylhexanoate/dibutyltin dilaurate. When the compounding ratio is 1 or more, gelation may be easily caused by the balance of catalytic activity.

In the case of using a catalyst when obtaining a polyurethane polyol, the amount of the catalyst to be used is preferably 0.01 to 1.0% by weight relative to the total amount of the polyester polyol (a1), the polyether polyol (a2) and the organic polyisocyanate compound (a 3).

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

No catalyst may be used in obtaining the polyurethane polyol. In this case, the reaction temperature is preferably 100 ℃ or higher, more preferably 110 ℃ or higher. When the polyurethane polyol is obtained without a catalyst, the reaction is preferably carried out for 3 hours or more.

Examples of the method for obtaining the polyurethane polyol include: 1) a method of putting all of the polyester polyol, the polyether polyol, the catalyst, and the organic polyisocyanate into the flask, and 2) a method of putting the polyester polyol, the polyether polyol, and the catalyst into the flask and adding the organic polyisocyanate dropwise. As a method for obtaining the polyurethane polyol, the method of 2) is preferable in terms of 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, and acetone. Among these solvents, toluene is preferable.

[ A-2-1-b. polyol ]

Examples of the polyol include preferably polyester polyol, polyether polyol, polycaprolactone polyol, polycarbonate polyol and castor oil polyol. The polyol is more preferably a polyether polyol.

The polyester polyol can be obtained, for example, by esterification of a polyol component with 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, 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-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, pimelic 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' -biphenyldicarboxylic acid, and acid anhydrides thereof.

Examples of the polyether polyol include the following polyether polyols: polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide using water, low molecular weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol a, etc.), dihydroxybenzenes (catechol, resorcinol, hydroquinone, etc.), etc. as initiators. Specific examples thereof include polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

Examples of the polycaprolactone polyol include caprolactone-based polyester diols obtained by ring-opening polymerization of cyclic ester monomers such as e-caprolactone and e-valerolactone.

Examples of the polycarbonate polyol include: a polycarbonate polyol obtained by subjecting the polyol component and phosgene to a polycondensation reaction; polycarbonate polyols obtained by subjecting the above polyol component to ester exchange condensation with a carbonic acid diester such as dimethyl carbonate, diethyl carbonate, dipropyl carbonate, diisopropyl carbonate, dibutyl carbonate, ethylbutyl carbonate, ethylene carbonate, propylene carbonate, diphenyl carbonate, or dibenzyl carbonate; a copolymerized polycarbonate polyol obtained by using 2 or more of the above polyol components in combination; polycarbonate polyols obtained by subjecting the above-mentioned various polycarbonate polyols and a carboxyl group-containing compound to an esterification reaction; polycarbonate polyols obtained by etherification of the above-mentioned various polycarbonate polyols with a hydroxyl group-containing compound; polycarbonate polyols obtained by subjecting the above-mentioned various polycarbonate polyols and an ester compound to an ester exchange reaction; polycarbonate polyols obtained by subjecting the above-mentioned various polycarbonate polyols and a hydroxyl group-containing compound to an ester exchange reaction; polyester polycarbonate polyols obtained by polycondensation of the above polycarbonate polyols with dicarboxylic acid compounds; a copolymerized polyether polycarbonate polyol obtained by copolymerizing the above-mentioned various polycarbonate polyols with an alkylene oxide; and the like.

Examples of the castor oil polyol include castor oil polyols obtained by reacting a castor oil fatty acid with the above polyol component. Specifically, for example, castor oil-based polyols obtained by reacting castor oil fatty acids with polypropylene glycol are exemplified.

The number average molecular weight Mn of the polyol is preferably 300 to 100000, more preferably 400 to 75000, still more preferably 450 to 50000, and particularly preferably 500 to 30000. When the number average molecular weight Mn of the polyol is within the above range, the surface protection film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The polyol preferably contains a polyol (A1) having 3 OH groups and a number average molecular weight Mn of 300 to 100000. The number of the polyhydric alcohols (a1) may be only 1, or may be 2 or more.

The content of the polyol (a1) in the polyol is preferably 5% by weight or more, more preferably 25% by weight to 100% by weight, and still more 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 protection film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The number average molecular weight Mn of the polyol (A1) is preferably 1000 to 100000, more preferably more than 1000 and 80000 or less, further preferably 1100 to 70000, further preferably 1200 to 60000, further preferably 1300 to 50000, further preferably 1400 to 40000, further preferably 1500 to 35000, particularly preferably 1700 to 32000, 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 can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The polyol may contain a polyol (A2) having 3 or more OH groups and a number average molecular weight Mn of 20000 or less. The number of the polyhydric alcohols (a2) may be only 1, or may be 2 or more. The number average molecular weight Mn of the polyol (A2) is preferably 100 to 20000, more preferably 150 to 10000, further preferably 200 to 7500, particularly preferably 300 to 6000, most preferably 300 to 5000. If the number average molecular weight Mn of the polyol (a2) falls outside the above range, the surface protection film of the present invention may have a high increase in peeling force with time. The polyol (a2) is preferably a polyol (triol) having 3 OH groups, a polyol (tetraol) having 4 OH groups, a polyol (pentaol) having 5 OH groups, or a polyol (hexaol) having 6 OH groups.

The total amount of the polyol (tetraol) having 4 OH groups, the polyol (pentaol) having 5 OH groups, and the polyol (hexaol) having 6 OH groups as the polyol (a2) 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, based on the content ratio in the polyol. When the total amount of the polyol (a2) which is a polyol (tetraol) having 4 OH groups, the polyol (pentaol) having 5 OH groups, and the polyol (hexaol) having 6 OH groups is within the above range, the surface protective film of the present invention can provide an adhesive layer having excellent transparency, and the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The content of the polyol (a2) in the polyol is preferably 95 wt% or less, and more preferably 0 wt% to 75 wt%. When the content ratio of the polyol (a2) in the polyol is within the above range, the surface protection film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The content of the polyol having 4 or more OH groups and a number average molecular weight Mn of 20000 or less as the polyol (a2) is preferably less than 70% by weight, more preferably 60% by weight or less, still more preferably 50% by weight or less, particularly preferably 40% by weight or less, and most preferably 30% by weight or less, based on the total amount of the polyol. When the content ratio of the polyol having 4 or more OH groups and a number average molecular weight Mn of 20000 or less as the polyol (a2) is within the above range with respect to the entire polyol, the pressure-sensitive adhesive layer having excellent transparency can be provided, and the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

[ A-2-1-c. acrylic resin ]

As the acrylic resin, any suitable acrylic adhesive such as a known acrylic adhesive described in japanese patent application laid-open publication No. 2013-241606 and the like can be used as long as the effects of the present invention are not impaired.

The acrylic resin may contain any appropriate component within a range not impairing the effects of the present invention. Examples of such components include resin components other than acrylic resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, anti-aging agents, conductive agents, ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts, and the like.

[ A-2-1-d. rubber-based resin ]

As the rubber-based resin, any suitable rubber-based adhesive such as a known rubber-based adhesive described in japanese patent application laid-open publication No. 2015-074771 and the like can be used as long as the effects of the present invention are not impaired. These may be 1 kind only or 2 or more kinds.

The rubber-based resin may contain any appropriate component within a range not impairing the effects of the present invention. Examples of such components include resin components other than rubber-based resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, anti-aging agents, conductive agents, ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts, and the like.

[ A-2-1-e. Silicone resin ]

As the silicone resin, any suitable silicone adhesive such as a known silicone adhesive described in, for example, japanese patent application laid-open publication No. 2014-047280 can be used as long as the effects of the present invention are not impaired. These may be 1 kind only or 2 or more kinds.

The silicone resin may contain any suitable component within a range not impairing the effects of the present invention. Examples of such components include resin components other than silicone resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, anti-aging agents, conductive agents, ultraviolet absorbers, 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 1 type or 2 or more types.

The low-molecular-weight polyol may be any suitable low-molecular-weight polyol within a range not impairing the effects of the present invention. Examples of such a low molecular weight polyol include polyols having a number average molecular weight Mn of 1500 or less.

The number average molecular weight Mn of the low-molecular-weight polyol is preferably 1400 or less, more preferably 1300 or less, further 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, further 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 can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

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

Examples of the polyether polyol include the following polyether polyols: polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide using water, low molecular weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol a, etc.), dihydroxybenzenes (catechol, resorcinol, hydroquinone, etc.), etc. as initiators. Specific examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and polyoxypropylene glycerol ether.

The number of OH groups of the low-molecular-weight polyol is preferably 2 to 6, more preferably 3 to 5, further preferably 3 to 4, and particularly preferably 3. When the low-molecular-weight polyol has an OH group number within the above range, the surface protective film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

< A-2-3. Silicone additives >

The silicone additive may be any suitable silicone additive as long as the effects of the present invention are not impaired. The silicone additive preferably includes at least 1 selected from a silicone bond-containing compound, a hydroxyl group-containing silicone compound, and a crosslinkable functional group-containing silicone compound, and more preferably a hydroxyl group-containing silicone compound.

The number of the silicone additives may be only 1, or may be 2 or more.

Examples of the compound having a siloxane bond include polyether-modified polyorganosiloxanes obtained by introducing polyether groups into the main chain or side chain of a polyorganosiloxane skeleton (such as polydimethylsiloxane), polyester-modified polyorganosiloxanes obtained by introducing polyester groups into the main chain or side chain of a polyorganosiloxane skeleton, polyorganosiloxanes introduced into organic compounds obtained by introducing organic compounds into the main chain or side chain of a polyorganosiloxane skeleton, silicone-modified (meth) acrylic resins obtained by introducing polyorganosiloxanes into (meth) acrylic resins, silicone-modified organic compounds obtained by introducing polyorganosiloxanes into organic compounds, and silicone-containing organic compounds obtained by copolymerizing organic compounds and organic compounds. Examples of commercially available products of such siloxane bond-containing polymers include those having the trade name "LE-302" (manufactured by Kyoeisha chemical Co., Ltd.), and BYK series leveling agents ("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", and the like, "BYK-377", "BYK-378", "BYK-UV 3500", "BYK-UV 3510", "BYK-UV 3570", "BYK-3550", "BYK-SILCLEAN 3700", "BYK-SILCLEAN 3720", etc.), AC series leveling agents ("AC FS 180", "AC FS 360", "AC S20", etc.) manufactured by Algin Chemie, POLYFLOW series leveling agents ("POLYFLOW KL-400X", "POLYFLOW KL-400 HF", "POLYFLOW KL-401", "POLYFLOW KL-402", "POLYFLOW KL-403", "POLYFLOW KL-404", etc.) manufactured by Kp series of Kanji Kabushiki Kaisha ("KP-323", "KP-326", "KP-341", "KP-104", "KP-110", "KP-112", etc.), and Kx series leveling agents ("KP-32 KP-22", etc.) manufactured by Kyoki Kanji Kaisha, KF series, Dow Corning Toray Co., Ltd., "LP-7001", "LP-7002", "8032 ADDITIVE", "57 ADDITIVE", "L-7604", "FZ-2110", "FZ-2105", "67 ADDITIVE", "8618 ADDITIVE", "3 ADDITIVE", "56 ADDITIVE", etc.).

Examples of the hydroxyl group-containing silicone compound include polyether-modified polyorganosiloxanes obtained by introducing polyether groups into the main chain or side chain of a polyorganosiloxane skeleton (such as polydimethylsiloxane), polyester-modified polyorganosiloxanes obtained by introducing polyester groups into the main chain or side chain of a polyorganosiloxane skeleton, polyorganosiloxanes introduced into organic compounds obtained by introducing organic compounds into the main chain or side chain of a polyorganosiloxane skeleton, silicone-modified (meth) acrylic resins obtained by introducing polyorganosiloxanes into (meth) acrylic resins, silicone-modified organic compounds obtained by introducing polyorganosiloxanes into organic compounds, and silicone-containing organic compounds obtained by copolymerizing organic compounds and organic compounds. Among these, the hydroxyl group may be contained in the 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 of such a hydroxyl group-containing silicone compound include trade names "X-22-4015", "X-22-4039", "KF 6000", "KF 6001", "KF 6002", "KF 6003", "X-22-170 BX", "X-22-170 DX", "X-22-176F" (manufactured by shin-Etsu chemical Co., Ltd.), and "BYK-370", "BYK-SILCLEAN 3700" and "BYK-SILCLEAN 3720" manufactured by BYK Japan KK..

Examples of the crosslinkable functional group-containing silicone compound include polyether-modified polyorganosiloxanes obtained by introducing polyether groups into the main chain or side chain of a polyorganosiloxane skeleton (such as polydimethylsiloxane), polyester-modified polyorganosiloxanes obtained by introducing polyester groups into the main chain or side chain of a polyorganosiloxane skeleton, polyorganosiloxanes introduced into organic compounds obtained by introducing organic compounds into the main chain or side chain of a polyorganosiloxane skeleton, silicone-modified (meth) acrylic resins obtained by introducing polyorganosiloxanes into (meth) acrylic resins, silicone-modified organic compounds obtained by introducing polyorganosiloxanes into organic compounds, and silicone-containing organic compounds obtained by copolymerizing organic compounds and organosilicon compounds. Among these, the crosslinkable functional group may be contained in the 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 amino, epoxy, mercapto, carboxyl, isocyanate and methacrylate groups. Examples of commercially available products of such an isocyanate group-containing silicone include "BY 16-855", "SF 8413", "BY 16-839", "SF 8421", "BY 16-750", "BY 16-880", "BY 16-152C" manufactured BY Ltd, "KF-868", "KF-865", "KF-864", "KF-859", "KF-393", "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-8004 ", KF-8005", "KF-867", "KF-8021", "KF-869", "KF-861", "X-22-343", "KF-101", "X-22-2000", and "X-22-4741", manufactured BY Ltd "KF-1002", "KF-2001", "X-22-3701E", "X-22-164A", "X-22-164B", "X-22-164 AS", "X-22-2445", etc.

< A-2-4. fluorine-based additive >

The fluorine-based additive may be any suitable fluorine-based additive within a range not impairing the effects of the present invention. The fluorine-containing additive preferably includes at least 1 selected from a fluorine-containing compound, a hydroxyl group-containing fluorine-containing compound, and a crosslinkable functional group-containing fluorine-containing compound. The fluorine-based compound containing a hydroxyl group is preferable in that the effects of the present invention can be further exhibited.

The fluorine-containing additive may be 1 kind or 2 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 fluorinated C1-C10 alkanes such as fluoromethane, fluoroethane, fluoropropane, fluoroisopropane, fluorobutane, fluoroisobutane, fluorot-butane, fluoropentane and fluorohexane. Examples of commercially available products of such fluorine-containing compounds include Surflon-series leveling agents ("S-242", "S-243", "S-420", "S-611", "S-651" and "S-386" manufactured by AGC Seimi Chemical Co., Ltd.), BYK-series leveling agents ("BYK-340" and the like) manufactured by BYK Japan KK., AC-series leveling agents ("AC 110 a" and "AC 100 a" and the like) manufactured by Algin Chemie, MEGAFACE-series leveling agents ("MEGAFACE F-114", "MEGAFACE F-410", "MEGAFACE F-444", "MEGAFACE EXP TP-2066", "MEGAFACE F-430", "MEGAFACE F-SF 472", "MEGAFACE F-477", "MEGAFACE F-552", "MEGAFACE F-554", "MEGAFACE F-554"), "MEGAFACE F-555", "MEGAFACE R-94", "MEGAFACE RS-72-K", "MEGAFACE RS-75", "MEGAFACE F-556", "MEGAFACE EXP TF-1367", "MEGAFACE EXP TF-1437", "MEGAFACE F-558", "MEGAFACE EXP TF-1537", etc.), FC series leveling agents manufactured by Sumitomo 3M Limited ("FC-4430", "FC-4432", etc.), Ftergent series leveling agents manufactured by NEOS company ("Ftergent 100", "Ftergent 100C", "Ftergent 110", "Ftergent 150 CH", "Ftergent A-K", "Ftergent 501", "Ftergent 250", "Ftergent 251", "Ftergent 222F", "Ftergent 208G", "terFgent 300", "Ftergent 310", "Ftergent 400" SW, etc.), North chemical industry series leveling agents manufactured by North chemical industries ("PF-A", PF-136 ", etc.", "PF-156A", "PF-151N", "PF-636", "PF-6320", "PF-656", "PF-6520", "PF-651", "PF-652", "PF-3320", etc.), etc.

Examples of the hydroxyl group-containing fluorine-based compound include conventionally known resins, and examples thereof include hydroxyl group-containing fluororesins described in pamphlet of international publication No. 94/06870, japanese patent application laid-open No. 8-12921, japanese patent application laid-open No. 10-72569, japanese patent laid-open No. 4-275379, international publication No. 97/11130, and international publication No. 96/26254. Examples of the other hydroxyl group-containing fluororesin include fluoroolefin copolymers described in, for example, Japanese patent application laid-open Nos. 8-231919, 10-265731, 10-204374 and 8-12922. Examples of the fluorine-containing compound include 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, and a fluorine-containing compound containing a hydroxyl group-containing organic compound. Examples of commercially available products of such hydroxyl group-containing fluorine-based compounds include trade names "LUMIFLON" (manufactured by Asahi glass company, Ltd.), trade names "Cefralacoat" (manufactured by Mitsui glass company, Ltd.), trade names "Zaflo" (manufactured by Toyo Seisakusho K.K.), trade names "ZEFFLE" (manufactured by DAIKIN INDUSTRIES, Ltd.), trade names "MEGAFACE F-571" and "FLUONATE" (manufactured by DIC).

Examples of the crosslinkable functional group-containing fluorine-based compound include a carboxylic acid compound having a fluorinated alkyl group such as perfluorooctanoic acid, a copolymer of a compound having a fluorinated alkyl group among crosslinkable functional group-containing compounds, a fluorine-containing organic compound obtained by copolymerizing a fluorine-containing compound and a crosslinkable functional group-containing compound, and a fluorine-containing compound containing a crosslinkable functional group-containing compound. Examples of commercially available products of such crosslinkable functional group-containing fluorine-based compounds include, for example, the trade names "MEGAFACE F-570", "MEGAFACE RS-55", "MEGAFACE RS-56", "MEGAFACE RS-72-K", "MEGAFACE RS-75", "MEGAFACE RS-76-E", "MEGAFACE RS-76-NS", "MEGAFACE RS-78" and "MEGAFACE RS-90" (available from DIC).

By using a low molecular weight polyol in combination with a silicone-based additive and/or a fluorine-based additive, the following surface protective film can be provided: it is less likely to peel off from an adherend, and even when stored for a long period of time in a severe environment, the occurrence of re-peeling over time can be more sufficiently suppressed, and the staining of the adherend surface by attachment to an adherend is sufficiently low.

When the low-molecular-weight polyol and the silicone-based additive and/or the fluorine-based additive are used in combination, the content of the low-molecular-weight polyol in the binder composition is preferably 0.01 to 50 parts by weight, more preferably 0.05 to 25 parts by weight, further preferably 0.07 to 30 parts by weight, further preferably 0.1 to 20 parts by weight, further preferably 0.3 to 15 parts by weight, particularly preferably 0.5 to 10 parts by weight, and most preferably 0.7 to 7.0 parts by weight, based on 100 parts by weight of the base polymer. 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 binder composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

When the low molecular weight polyol and the silicone additive and/or the fluorine additive are used in combination, the content of the silicone additive and/or the fluorine additive in the adhesive composition is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, further preferably 0.01 to 10 parts by weight, further preferably 0.01 to 1 part by weight, further preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer, relative to the total amount of the silicone additive and the fluorine additive. 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 silicone-based additive and/or the fluorine-based additive in the binder composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low. Specifically, the following is described.

When the low molecular weight polyol and the silicone additive are used in combination but the fluorine additive is not used in combination, the content of the silicone additive in the adhesive composition is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, further preferably 0.01 to 10 parts by weight, further preferably 0.01 to 1 part by weight, further preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer. 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, if the content of the silicone-based additive in the adhesive composition is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

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 adhesive composition is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, further preferably 0.01 to 10 parts by weight, further preferably 0.01 to 1 part by weight, further preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer. 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, if the content of the fluorine-based additive in the adhesive composition is within the above range, the surface protection film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

When the low-molecular-weight polyol, the silicone additive and the fluorine additive are used in combination, the total content of the silicone additive and the fluorine additive is preferably 0.001 to 50 parts by weight, more preferably 0.005 to 25 parts by weight, further preferably 0.01 to 10 parts by weight, further preferably 0.01 to 1 part by weight, further preferably 0.01 to 0.50 parts by weight, particularly preferably 0.01 to 0.30 parts by weight, and most preferably 0.01 to 0.10 parts by weight, based on 100 parts by weight of the base polymer. When the low-molecular-weight polyol, the silicone additive and the fluorine additive are used in combination, if the total content ratio of the silicone additive and the fluorine additive in the binder composition is within the above range, the surface protection film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

< A-2-5. urethane resin >

The urethane prepolymer and the polyol as the base polymer may be combined with the polyfunctional isocyanate compound (B) to be components of a composition for forming a urethane resin. By using the above-mentioned substances as the components for forming the urethane resin composition, the surface protection film of the present invention can further exhibit the following effects: the adhesive is not easily peeled from an adherend, can sufficiently suppress the occurrence of re-peeling over time even when the initial peeling force after the attachment to the adherend is large, and has sufficiently low staining of the adherend surface due to the attachment to the adherend.

The composition for forming a urethane resin may contain any appropriate other component within a range not impairing the effects of the present invention. Examples of such components include resin components other than urethane resins, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, anti-aging agents, conductive agents, ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, polymerization inhibitors, lubricants, solvents, catalysts, and the like.

The composition for forming a urethane resin preferably contains an anti-deterioration agent such as an antioxidant, an ultraviolet absorber, and a light stabilizer. By including the deterioration preventing agent in the composition for forming a urethane resin, even if the formed pressure-sensitive adhesive layer is stored in a heated state after being attached to an adherend, the adhesive residue and the like are less likely to occur on the adherend, and the excellent adhesive residue prevention property is obtained. The number of the deterioration preventing agents may be only 1, or may be 2 or more. As the deterioration preventing agent, an antioxidant is particularly preferable.

Examples of the antioxidant include a radical chain inhibitor and a peroxide decomposer.

Examples of the radical chain inhibitor include a phenol-based antioxidant and an amine-based antioxidant.

Examples of the peroxide decomposer include a sulfur-based antioxidant, a phosphorus-based antioxidant and the like.

Examples of the phenol antioxidant include monophenol antioxidants, bisphenol antioxidants, and high-molecular phenol antioxidants.

Examples of the monophenol-based antioxidant include 2, 6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2, 6-di-t-butyl-4-ethylphenol, and stearyl β - (3, 5-di-t-butyl-4-hydroxyphenyl) propionate.

Examples of the bisphenol-based antioxidant include 2,2 '-methylenebis (4-methyl-6-tert-butylphenol), 2' -methylenebis (4-ethyl-6-tert-butylphenol), 4 '-thiobis (3-methyl-6-tert-butylphenol), 4' -butylidenebis (3-methyl-6-tert-butylphenol), 3, 9-bis [1, 1-dimethyl-2- [ β - (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy ] ethyl ]2,4,8, 10-tetraoxaspiro [5,5] undecane, and the like.

Examples of the high-molecular-weight phenol-based 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) butyrate ] diol ester, 1,3, 5-tris (3 ', 5 ' -di-t-butyl-4 ' -hydroxybenzyl) -s-triazine-2, 4,6- (1H,3H,5H) triketones, tocopherols, and the like.

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 triphenyl phosphite, diphenylisodecyl phosphite, and phenyldiisodecyl phosphite.

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

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

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' -octyloxyphenyl) benzotriazole, 2-bis (t-butylphenyl) benzotriazole, and the like, 2- [2 '-hydroxy-3' - (3 ", 4", 5 ", 6" -tetrahydrophthalimidomethyl) -5 '-methylphenyl ] benzotriazole, 2' -methylenebis [4- (1,1,3, 3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol ], 2- (2 '-hydroxy-5' -methacryloxyphenyl) -2H-benzotriazole, and the like.

Examples of the salicylic acid-based ultraviolet absorber include phenyl salicylate, p-tert-butyl phenyl salicylate, and p-octyl phenyl salicylate.

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 light stabilizers and ultraviolet light 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.

Examples of the ultraviolet light stabilizer include bis (octylphenyl) nickel sulfide, [2, 2' -thiobis (4-tert-octylphenol) ] -n-butylamine nickel, 3, 5-di-tert-butyl-4-hydroxybenzyl-phosphoric acid monoethanol nickel complex, dibutyl dithiocarbamate nickel, benzoate-type quencher, dibutyl dithiocarbamate nickel, 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 resin formed from the composition containing the urethane prepolymer and the polyfunctional isocyanate compound (B) includes, for example, a urethane resin formed from a composition containing a urethane polyol as the urethane prepolymer and the polyfunctional isocyanate compound (B).

The number of urethane prepolymers may be only 1, or may be 2 or more.

The number of the polyfunctional isocyanate compounds (B) may be only 1, or may be 2 or more.

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

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

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

Examples of the polyfunctional aromatic diisocyanate compound include phenylene diisocyanate, 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate, 2 '-diphenylmethane diisocyanate, 4' -toluidine diisocyanate, 4 '-diphenyl ether diisocyanate, 4' -diphenyl diisocyanate, 1, 5-naphthalene diisocyanate, and xylylene diisocyanate.

Examples of the polyfunctional isocyanate compound (B) include trimethylolpropane adducts, biuret products obtained by reaction with water, and trimers having an isocyanurate ring of the above polyfunctional isocyanate compounds. Further, they may be used in combination.

In the composition containing the urethane prepolymer and the polyfunctional isocyanate compound (B), any suitable other component may be contained within a range not impairing the effects of the present invention. Examples of such other components include resin components other than the urethane resin, a thickener, an inorganic filler, an organic filler, metal powder, a pigment, a foil, a softener, an antioxidant, a conductive agent, an ultraviolet absorber, an antioxidant, a light stabilizer, a surface lubricant, a leveling agent, an anticorrosive agent, a heat stabilizer, a polymerization inhibitor, a lubricant, a solvent, a catalyst, and the like.

As a method for forming a polyurethane-based resin from a composition containing a urethane prepolymer and a polyfunctional isocyanate compound (B), any suitable production method can be employed as long as the polyurethane-based resin is produced using a so-called "urethane prepolymer" as a raw material.

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

The equivalent ratio of NCO groups to OH groups in the urethane prepolymer and the polyfunctional isocyanate compound (B) is preferably 5.0 or less, more preferably 0.01 to 4.75, further preferably 0.02 to 4.5, particularly preferably 0.03 to 4.25, and most preferably 0.05 to 4.0 in terms of NCO groups/OH groups. When the equivalent ratio of NCO groups/OH groups is within the above range, the surface protective film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The content of the polyfunctional isocyanate compound (B) is preferably 0.01 to 30% by weight, more preferably 0.05 to 25% by weight, still more preferably 0.1 to 20% by weight, particularly preferably 0.5 to 17.5% by weight, and most preferably 1 to 15% by weight, based on the urethane prepolymer. When the content ratio of the polyfunctional isocyanate compound (B) is within the above range, the surface protective film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

[ A-2-5-b. urethane resin formed from a composition containing a polyol and a polyfunctional isocyanate compound (B) ]

The urethane resin formed from the composition containing the polyol and the polyfunctional isocyanate compound (B) is specifically preferably a urethane resin obtained by curing a composition containing the polyol and the polyfunctional isocyanate compound (B).

The number of the polyhydric alcohols may be only 1, or may be 2 or more.

The number of the polyfunctional isocyanate compounds (B) may be only 1, or may be 2 or more.

As the polyfunctional isocyanate compound (B), the aforementioned compounds can be used.

The equivalent ratio of NCO groups to OH groups in the polyol (A) and the polyfunctional isocyanate compound (B) is preferably 5.0 or less, more preferably 0.1 to 3.0, further preferably 0.2 to 2.5, particularly preferably 0.3 to 2.25, and most preferably 0.5 to 2.0 in terms of NCO groups/OH groups. When the equivalent ratio of NCO groups/OH groups is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The content of the polyfunctional isocyanate compound (B) is preferably 1.0 to 30% by weight, more preferably 1.5 to 27% by weight, even more preferably 2.0 to 25% by weight, particularly preferably 2.3 to 23% by weight, and most preferably 2.5 to 20% by weight, based on the polyol. When the content ratio of the polyfunctional isocyanate compound (B) is within the above range, the surface protective film of the present invention can exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

Specifically, the polyurethane resin is preferably formed by curing a composition containing a polyol and a polyfunctional isocyanate compound (B). As a method for forming a urethane resin by curing a composition containing a polyol and a polyfunctional isocyanate compound (B), any appropriate method such as a urethanization reaction method using bulk polymerization, solution polymerization, or the like can be employed within the range not impairing the effects of the present invention.

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

Examples of the organometallic compound include an iron-based compound, a tin-based compound, a titanium-based compound, a zirconium-based compound, a lead-based compound, a cobalt-based compound, and a zinc-based compound. 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 methoxide, tributyltin acetate, triethyltin acetate, tributyltin acetate, dioctyltin oxide, dioctyltin dilaurate, tributyltin chloride, tributyltin trichloroacetate, and tin 2-ethylhexanoate.

Examples of the titanium compound include dibutyltitanium 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, and lead naphthenate.

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, and 1, 8-diazabicyclo- (5,4,0) -undec-7-ene.

The number of the catalyst may be only 1, or may be 2 or more. In addition, a catalyst, a crosslinking retarder, and the like may be used in combination. The amount of the catalyst is preferably 0.005 to 1.00% by weight, more preferably 0.01 to 0.75% by weight, still more preferably 0.01 to 0.50% by weight, particularly preferably 0.01 to 0.20% by weight, based on the polyol. When the amount of the catalyst is within the above range, the surface protective film of the present invention can further exhibit the following effects: the adhesive sheet is less likely to be peeled from an adherend, and even if the initial peeling force after the adhesive sheet is attached to the adherend is large, the releasability over time can be more sufficiently suppressed, and the staining of the surface of the adherend due to the attachment to the adherend is sufficiently low.

The composition containing the polyol and the polyfunctional isocyanate compound (B) may contain any other suitable component within a range not impairing the effects of the present invention. Examples of such other components include resin components other than the urethane resin, a thickener, an inorganic filler, an organic filler, metal powder, a pigment, a foil, a softener, an antioxidant, a conductive agent, an ultraviolet absorber, an antioxidant, a light stabilizer, a surface lubricant, a leveling agent, an anticorrosive agent, a heat stabilizer, a polymerization inhibitor, a lubricant, a solvent, a catalyst, and the like.

< A-2-6. other ingredients >

The adhesive composition may contain any suitable other component within a range not impairing the effects of the present invention. Examples of such other components include other resin components, tackifiers, inorganic fillers, organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, ultraviolet absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, anticorrosion agents, polymerization inhibitors, lubricants, solvents, catalysts, and the like.

The adhesive composition may comprise an ionic liquid comprising a fluoro organic anion. By including an ionic liquid containing a fluorine organic anion in the adhesive composition, an adhesive composition having very excellent antistatic properties can be provided. Such ionic liquids may be only 1 type, or may be 2 or more types.

In the present invention, the ionic liquid is a molten salt (ionic compound) that is in a liquid state at 25 ℃.

As the ionic liquid, any appropriate ionic liquid may be used as long as it contains a fluorine organic anion, within a range not impairing the effects of the present invention. The ionic liquid is preferably an ionic liquid composed of a fluorine organic anion and an onium cation. By using an ionic liquid composed of a fluorine organic anion and an onium cation as the ionic liquid, an adhesive composition having very excellent antistatic properties can be provided.

As the onium cation which can constitute the ionic liquid, any appropriate onium cation may be used within a range not impairing the effects of the present invention. The onium cation is preferably at least 1 selected from the group consisting of nitrogen-containing onium cations, sulfur-containing onium cations, and phosphorus-containing onium cations. By selecting these onium cations, an adhesive composition excellent in antistatic property can be provided.

As the fluoroorganic anion that can constitute the ionic liquid, any suitable fluoroorganic anion can be used within a range that does not impair the effects of the present invention. Such fluoroorganic anions may be fully fluorinated (perfluorinated) or partially fluorinated.

Examples of such a fluorine organic anion include a fluorinated arylsulfonate, a perfluoroalkanesulfonate, a bis (fluorosulfonyl) imide, a bis (perfluoroalkanesulfonyl) imide, a cyano perfluoroalkanesulfonylamide, a bis (cyano) perfluoroalkanesulfonyl methide, a cyano-bis- (perfluoroalkanesulfonyl) methide, a tris (perfluoroalkanesulfonyl) methide, a trifluoroacetate, a perfluoroalkyl compound, a tris (perfluoroalkanesulfonyl) methide, and a (perfluoroalkanesulfonyl) trifluoroacetamide.

The ionic liquid may be a commercially available ionic liquid, or may be synthesized as described below. The method for synthesizing the ionic liquid is not particularly limited as long as the target ionic liquid can be obtained, and a halide method, a hydroxide method, an acid ester method, a complex formation method, a neutralization method, and the like, which are described in the literature "ionic liquid-the first and future of development" (published by CMC Publishing co., ltd.) can be generally used.

The amount of the ionic liquid to be blended is not limited in any way since it varies depending on the compatibility of the polymer to be used and the ionic liquid, but is usually preferably 0.001 to 50 parts by weight, more preferably 0.01 to 40 parts by weight, further preferably 0.01 to 30 parts by weight, particularly preferably 0.01 to 20 parts by weight, most preferably 0.01 to 10 parts by weight, based on 100 parts by weight of the base polymer. By adjusting the amount of the ionic liquid to be blended within the above range, an adhesive composition having very excellent antistatic properties can be provided. When the amount of the ionic liquid added is less than 0.01 parts by weight, sufficient antistatic properties may not be obtained. When the amount of the ionic liquid added exceeds 50 parts by weight, the adherend tends to be contaminated more.

The adhesive composition may contain a modified silicone oil within a range not impairing the effects of the present invention. By allowing the adhesive composition to contain the modified silicone oil, the effect of antistatic properties can be exhibited. In particular, the antistatic effect can be more effectively exhibited by using the ionic liquid in combination.

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

As the modified silicone oil, any suitable modified silicone oil may be used within a range not impairing the effects of the present invention. Examples of such modified silicone oils include those available from shin-Etsu chemical Co.

The modified silicone oil is preferably a polyether-modified silicone oil. By using the polyether-modified silicone oil, the antistatic property can be further effectively exhibited.

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

"use in B

The surface protection film of the present invention can exhibit the following effects: the adhesive is not easily peeled from an adherend, can sufficiently suppress the occurrence of re-peeling over time even when the initial peeling force after the attachment to the adherend is large, and has sufficiently low staining of the adherend surface due to the attachment to the adherend. Therefore, the resin composition can be suitably used for surface protection of optical members and electronic members. The surface protective film of the present invention is attached to the optical member of the present invention. The surface protective film of the present invention is attached to the electronic component of the present invention.

Examples

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to these examples at all. The test and evaluation methods in examples and the like are as follows. In the case where "part" is described, unless otherwise specified, "part by weight" is meant, and in the case where "%" is described, unless otherwise specified, "wt%".

< peeling force A from glass plate (after leaving at 23 ℃ C. for 30 minutes) >

The pressure-sensitive adhesive layer side from which the surface protection film (width 25 mm. times. length 140mm) of the separator was peeled was bonded to a glass plate (soda-lime glass, Songlanza corporation) by reciprocating a 2kg hand roller 1 time, and the glass plate was left at an ambient temperature of 23 ℃ for 30 minutes.

The evaluation sample obtained as described above was measured with a tensile tester. As the tensile testing machine, a high speed model (AG-50NX plus) was used under the trade name "Autograph AG-Xplus HS6000 mm/min", manufactured by Shimadzu corporation. The test piece for evaluation was set on a tensile tester, and a tensile test was started. Specifically, the load at the time of peeling the surface protection film from the glass plate was measured, and the average load at that time was taken as the peeling force a of the surface protection film from the glass plate. The conditions for the tensile test were: test environment temperature: 23 ℃ and peel angle: 180 degrees, peeling speed (stretching speed): 300 mm/min.

< peeling force B from glass plate (after leaving at a temperature of 100 ℃ C. for 2 days) >

The pressure-sensitive adhesive layer side from which the surface protection film (width 25 mm. times. length 140mm) of the separator was peeled was bonded to a glass plate (soda-lime glass, Songlanzui Co., Ltd.) by reciprocating a 2kg hand roller 1 time, and the plate was left to stand at a temperature of 100 ℃ for 2 days.

The evaluation sample obtained as described above was measured with a tensile tester. As the tensile testing machine, a high speed model (AG-50NX plus) was used under the trade name "Autograph AG-Xplus HS6000 mm/min", manufactured by Shimadzu corporation. The test piece for evaluation was set on a tensile tester, and a tensile test was started. Specifically, the load at the time of peeling the surface protection film from the glass plate was measured, and the average load at this time was taken as the peeling force B of the surface protection film from the glass plate. The conditions for the tensile test were: test environment temperature: 23 ℃ and peel angle: 180 degrees, peeling speed (stretching speed): 300 mm/min.

< peeling force C from glass plate (after leaving at a temperature of 23 ℃ C. for 7 days) >

The pressure-sensitive adhesive layer side from which the surface protection film (width 25 mm. times. length 140mm) of the separator was peeled was bonded to a glass plate (soda-lime glass, Songlanza corporation) by reciprocating a 2kg hand roller 1 time, and the plate was left to stand at a temperature of 23 ℃ for 7 days.

The evaluation sample obtained as described above was measured with a tensile tester. As the tensile testing machine, a high speed model (AG-50NX plus) was used under the trade name "Autograph AG-Xplus HS6000 mm/min", manufactured by Shimadzu corporation. The test piece for evaluation was set on a tensile tester, and a tensile test was started. Specifically, the load at the time of peeling the surface protection film from the glass plate was measured, and the average load at that time was taken as the peeling force C of the surface protection film from the glass plate. The conditions for the tensile test were: test environment temperature: 23 ℃ and peel angle: 180 degrees, peeling speed (stretching speed): 300 mm/min.

< residual adhesion to glass plate at 23 >

The pressure-sensitive adhesive layer side of the surface protection film from which the separator was peeled was bonded to the entire surface of a glass plate (1.35 mm. times.10 cm, made of Sonlang Nitri) by reciprocating a 2kg hand roller 1 time, and the glass plate was stored at a temperature of 23 ℃ and a humidity of 55% RH for 24 hours, and then the surface protection film was peeled at a speed of 0.3 m/min to prepare a treated glass plate.

Then, a 19mm wide No.31B tape (manufactured by Rido electric Co., Ltd., substrate thickness: 25 μm) cut into a length of 150mm was attached to the surface of the treated glass plate from which the surface protection film was peeled by reciprocating the glass plate 1 time by a 2kg hand roller under an atmosphere of 23 ℃ and a humidity of 55% RH. After curing at 23 ℃ under an atmosphere of 55% RH for 30 minutes, the film was cured using a tensile tester (trade name "Autograph AG-Xplus HS6000 mm/min high speed model (AG-50NX plus)" manufactured by Shimadzu corporation) at a peel angle: 180 degrees, peeling speed: the adhesive force a was measured by peeling at 300 mm/min.

The adhesive force b of the 19mm wide No.31B tape was also measured for a glass plate (1.35 mm. times.10 cm, made of Sonlang Nitri) which had not been subjected to the above-described treatment for bonding and peeling the surface protective film.

The residual adhesion ratio was calculated by the following formula.

Residual adhesion rate (%) (adhesive force a/adhesive force b) × 100

The residual adhesion ratio is an index of how much the components of the pressure-sensitive adhesive layer of the surface protective film are transferred to the adherend and contaminate the surface of the adherend. The higher the value of the residual adhesion ratio is, the less likely the surface protection film to contaminate the surface of the adherend with the components of the pressure-sensitive adhesive layer is, and the lower the value of the residual adhesion ratio is, the more likely the surface protection film to contaminate the surface of the adherend with the components of the pressure-sensitive adhesive layer is.

< storage moduli X1, X2, Y1, Y2>

(sample preparation method)

The pressure-sensitive adhesive composition was applied to a release-treated surface of a 38 μm thick polyester film (trade name: MRF, manufactured by Mitsubishi chemical corporation) whose one surface was release-treated with silicone, with a thickness of 50 μm after drying, by a dip roll (fountain roll), and cured and dried at a drying temperature of 130 ℃ for a drying time of 3 minutes. In this manner, an adhesive layer is formed on the substrate. Then, a 38 μm thick polyester film (trade name: MRF, manufactured by Mitsubishi chemical corporation) having one surface thereof treated with a release treatment by silicone was coated on the surface of the pressure-sensitive adhesive layer so that the release-treated surface of the film was on the pressure-sensitive adhesive layer side. In this manner, a surface protective film for evaluation was produced. For the surface protection films for evaluation, the surface protection films at a temperature of 23 ℃ were used for the measurement of storage moduli X1 and X2, and the surface protection films at a temperature of 23 ℃ after being left at a temperature of 80 ℃ for 7 days were used for the measurement of storage moduli Y1 and Y2.

(measurement method)

From the obtained surface protection film for evaluation, only the pressure-sensitive adhesive layer was taken out, laminated so as to have a thickness of about 2mm, and punched out

Cylindrical pellets were prepared as a sample for measurement. Fixing the test sample to

The storage modulus G' of the parallel plate jig was calculated by using a dynamic viscoelasticity measuring apparatus (ARES, manufactured by Rheometrics). The measurement conditions are as follows. The "a E + b" described in the table means "a × 10" as is generally widely known^b”。

And (3) determination: shear mode

Temperature range: -70 ℃ to 150 DEG C

Temperature rise rate: 5 ℃ per minute

Frequency: 1Hz

[ production example 1 ]: production of urethane prepolymer solution A

In a polymerization experimental apparatus equipped with a 1L round-bottomed separable flask, a removable lid, a separatory funnel, a thermometer, a nitrogen introduction tube, a libichi condenser, a vacuum sealer, a stirring bar, and a stirring blade, 150g of polypropylene glycol (product name "sannii PP-2000", Mn ═ 2000, product name "sanyo chemical industries co., ltd.), 150g of polyester Polyol (product name" Kuraray Polyol P-2010 ", Mn ═ 2000, product name" cloniza co., ltd.), 110g of toluene (product name "donocao co., ltd.) as a solvent, and 0.041g of dibutyltin (IV) (product name" wako pure chemical industries co., ltd.) as a catalyst were charged, and nitrogen substitution was carried out at room temperature for 1 hour with stirring. Thereafter, 33.5g of hexamethylene diisocyanate (trade name "HDI" manufactured by Tosoh Corp.) was put into the reactor under stirring with a nitrogen stream, the temperature of the solution in the experimental apparatus was controlled to 90. + -. 2 ℃ by a water bath and maintained for 4 hours, 74.9g of polypropylene glycol (trade name "GP 1000", Mn 1000, manufactured by Sanyo chemical industries Co., Ltd.) was put into the reactor, the temperature of the solution in the experimental apparatus was controlled to 90. + -. 2 ℃ by a water bath and maintained for 2 hours, 25.4g of hexamethylene diisocyanate (trade name "HDI" manufactured by Tosoh Corp.) was put into the reactor, and the temperature of the solution in the experimental apparatus was controlled to 90. + -. 2 ℃ by a water bath and maintained for 2 hours, thereby obtaining a urethane prepolymer solution A. In addition, during the polymerization, toluene is preferably added dropwise in order to control the temperature during the polymerization and to prevent a decrease in stirring properties due to an increase in viscosity. The total amount of toluene added dropwise 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 was added in terms of the solid content of the polymer, 20.0 parts by weight of an isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.), 4.0 parts by weight of a heat resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF), 3.0 parts by weight of a polyol (trade name "sanyang chemical Industry co., ltd., manufactured by sanyo GP 250", Mn 250, manufactured by sanyo chemical industries, inc.) in terms of the solid content, and 0.05 parts by weight of a fluoropolymer (trade name "F-571", manufactured by DIC corporation) in terms of the solid content, and the mixture was diluted with ethyl acetate so that the solid content of the whole became 45 parts by weight, thereby obtaining an adhesive composition (1). The obtained adhesive composition (1) was applied to a polyester resin substrate (trade name "T100-75S", thickness 75 μm, manufactured by Mitsubishi chemical corporation) so that the thickness after drying became 75 μm, cured at a drying temperature of 130 ℃ for a drying time of 3 minutes, and dried. In this manner, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (1) was produced on the substrate. Then, a silicone-treated surface of a release sheet (product name "MRF 25", thickness 25 μm, manufactured by mitsubishi chemical corporation) having one surface thereof silicone-treated and a thickness of 25 μm and made of a polyester resin was bonded to the surface of the obtained pressure-sensitive adhesive layer, thereby obtaining a surface-protecting film (1). The obtained surface protection film (1) was aged at room temperature for 7 days and evaluated. The release sheet was peeled off immediately before evaluation. The results are shown in Table 2.

[ example 2]

A pressure-sensitive adhesive layer composed of the pressure-sensitive adhesive composition (2) was produced in the same manner as in example 1 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 as shown in table 1, thereby obtaining a surface protection film (2).

The results are shown in Table 2.

[ example 3 ]

A pressure-sensitive adhesive layer composed of the pressure-sensitive adhesive composition (3) was produced in the same manner as in example 1 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 as shown in table 1, thereby obtaining a surface protective film (3).

The results are shown in Table 2.

[ example 4 ]

A pressure-sensitive adhesive layer composed of the pressure-sensitive adhesive composition (4) was produced in the same manner as in example 1 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 as shown in table 1, thereby obtaining a surface protection film (4).

The results are shown in Table 2.

[ example 5]

A pressure-sensitive adhesive layer composed of the pressure-sensitive adhesive composition (5) was produced in the same manner as in example 1 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 as shown in table 1, thereby obtaining a surface protection film (5).

The results are shown in Table 2.

[ example 6 ]

As shown in table 1, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (6) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, but a heat-resistant stabilizer (trade name "IRGANOX 1135", manufactured by BASF) was used in an amount of 2.0 parts by weight in terms of solid content, to obtain a surface-protecting film (6). The results are shown in Table 2.

[ example 7 ]

A pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive composition (7) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used but a heat-resistant stabilizer (trade name "IRGANOX 1135", manufactured by BASF) was used in an amount of 4.0 parts by weight in terms of solid content, as shown in table 1, to obtain a surface-protecting film (7). The results are shown in Table 2.

[ example 8 ]

As shown in table 1, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (8) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, but a heat-resistant stabilizer (trade name "IRGANOX 1135", manufactured by BASF) was used in an amount of 8.0 parts by weight in terms of solid content, to obtain a surface-protecting film (8). The results are shown in Table 2.

[ example 9 ]

As shown in table 1, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (9) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, but a heat-resistant stabilizer (trade name "IRGANOX 1135", manufactured by BASF) was used in an amount of 10.0 parts by weight in terms of solid content, and a surface-protecting film (9) was obtained. The results are shown in Table 2.

[ example 10 ]

As shown in table 1, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (10) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, but a heat-resistant stabilizer (trade name "IRGANOX 1135", manufactured by BASF) was used in an amount of 15.0 parts by weight in terms of solid content, and a surface-protecting film (10) was obtained. The results are shown in Table 2.

[ example 11 ]

A pressure-sensitive adhesive layer composed of the pressure-sensitive adhesive composition (11) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "TINUVIN 765", manufactured by BASF) was added in an amount of 4.0 parts by weight in terms of solid content as shown in table 1, thereby obtaining a surface-protecting film (11). The results are shown in Table 2.

[ example 12 ]

As shown in table 1, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (12) was produced in the same manner as in example 1 except that a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, but a heat-resistant stabilizer (trade name "IRGANOX 1135", manufactured by BASF) was used in an amount of 4.0 parts by weight in terms of solid content, and a heat-resistant stabilizer (trade name "TINUVIN 765", manufactured by BASF) was additionally used in an amount of 4.0 parts by weight in terms of solid content, to obtain a surface-protecting film (12). The results are shown in Table 2.

[ example 13 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 18.8 parts by weight in terms of solid content, a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), a heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF) was additionally used in 4.0 parts by weight in terms of solid content, a polyhydric alcohol (trade name "sannii GP 250", Mn 250 ", manufactured by sanyo chemical industries co., ltd.) was not used, a fluorine-containing polymer (trade name" TMP ", Mn 134", manufactured by mitsubishi chemical corporation) was not used in 2.0 parts by weight in terms of solid content, and a fluorine-containing polymer (trade name "F-DIC", manufactured by mitsubishi chemical corporation) was not used, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (13) was prepared in the same manner as in example 1, to obtain a surface-protecting film (13). The results are shown in Table 2.

[ example 14 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 26.0 parts by weight in terms of solid content, a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), a heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF) was additionally used in 4.0 parts by weight in terms of solid content, a polyhydric alcohol (trade name "sannii GP 250", Mn 250 ", manufactured by sanyo chemical industries co., ltd.) was not used, a fluorine-containing polymer (trade name" TMP ", Mn 134", manufactured by mitsubishi chemical corporation) was not used in 3.0 parts by weight in terms of solid content, and a fluorine-containing polymer (trade name "F-DIC", manufactured by mitsubishi chemical corporation) was not used, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (14) was prepared in the same manner as in example 1, to obtain a surface-protecting film (14). The results are shown in Table 2.

[ example 15 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 33.2 parts by weight in terms of solid content, a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), a heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF) was additionally used in 4.0 parts by weight in terms of solid content, a polyhydric alcohol (trade name "sannii GP 250", Mn 250 ", manufactured by sanyo chemical industries co., ltd.) was not used, a fluorine-containing polymer (trade name" TMP ", Mn 134", manufactured by mitsubishi chemical corporation) was not used in 4.0 parts by weight in terms of solid content, and a fluorine-containing polymer (trade name "F-DIC", manufactured by mitsubishi chemical corporation) was not used, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (15) was prepared in the same manner as in example 1, to obtain a surface-protecting film (15). The results are shown in Table 2.

[ example 16 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 40.8 parts by weight in terms of solid content, a heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), a heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF) was additionally used in 4.0 parts by weight in terms of solid content, a polyhydric alcohol (trade name "sannii GP 250", Mn 250 ", manufactured by sanyo chemical industries co., ltd.) was not used, a fluorine-containing polymer (trade name" TMP ", Mn 134", manufactured by mitsubishi chemical corporation) was not used in 5.0 parts by weight in terms of solid content was used, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (16) was prepared in the same manner as in example 1, to obtain a surface-protecting film (16). The results are shown in Table 2.

[ example 17 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 18.8 parts by weight in terms of solid content, the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), 4.0 parts by weight in terms of solid content was used as the heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF), the polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries) was not used, 2.0 parts by weight in terms of solid content was used as the trimethylolpropane (trade name "TMP", Mn 134, manufactured by mitsubishi chemical corporation) was used, and the fluoropolymer (trade name "F-DIC", manufactured by mitsubishi chemical corporation) was changed to 0.571 parts by weight in terms of solid content, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (17) was prepared in the same manner as in example 1, to obtain a surface-protecting film (17). The results are shown in Table 2.

[ example 18 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 26.0 parts by weight in terms of solid content, the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), 4.0 parts by weight in terms of solid content was used as the heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF), the polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries) was not used, the amount of the fluorine-containing polymer (trade name "F-DIC", manufactured by sanwa chemical corporation) was changed to 571 parts by solid content, and the amount of the fluorine-containing polymer (trade name "TMP", Mn 134, manufactured by sanwa chemical corporation) was changed to 0.571 parts by weight in terms of solid content, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (18) was prepared in the same manner as in example 1, to obtain a surface-protecting film (18). The results are shown in Table 2.

[ example 19 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 33.2 parts by weight in terms of solid content, the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), 4.0 parts by weight in terms of solid content was used as the heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF), the polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries) was not used, the amount of the fluorine-containing polymer (trade name "F-DIC", manufactured by sanwa chemical corporation) was changed to 571 parts by solid content, and the amount of the fluorine-containing polymer (trade name "TMP", Mn 134, manufactured by sanwa chemical corporation) was changed to 0.571 parts by weight in terms of solid content, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (19) was prepared in the same manner as in example 1, to obtain a surface-protecting film (19). The results are shown in Table 2.

[ example 20 ]

As shown in table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry co., ltd.) was changed to 40.6 parts by weight in terms of solid content, the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was not used, 4.0 parts by weight in terms of solid content was used (trade name "IRGANOX 1135", manufactured by BASF), 4.0 parts by weight in terms of solid content was used as the heat-resistant stabilizer (trade name "tivin nu765", manufactured by BASF), the polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries) was not used, 5.0 parts by weight in terms of solid content was used as the trimethylolpropane (trade name "TMP", Mn 134, manufactured by mitsubishi chemical corporation) was used, and the fluoropolymer (trade name "F-DIC", manufactured by mitsubishi chemical corporation) was changed to 0.571 parts by solid content, except for this, a pressure-sensitive adhesive layer formed of the pressure-sensitive adhesive composition (20) was prepared in the same manner as in example 1, to obtain a surface-protecting film (20). The results are shown in Table 2.

[ example 21 ]

As shown in Table 1, the amount of the isocyanate-based crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry Co., Ltd.) was changed to 16.0 parts by weight in terms of solid content, 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 (trade name "IRGANOX 1135", manufactured by BASF), the amount of the polyol (trade name "SANNIX GP 250", Mn 250 ", manufactured by Sanyo chemical industries Co., Ltd.) was changed to 1.5 parts by weight in terms of solid content, the fluoropolymer (trade name" F-571 ", manufactured by DIC Co., Ltd.) was changed to 0.05 parts by weight in terms of solid content of the hydroxyl-containing silicone (trade name" X-22-4015 ", manufactured by shin chemical industries Co., Ltd.) and the same procedure as in example 1 was conducted, a pressure-sensitive adhesive layer formed from the pressure-sensitive adhesive composition (21) was prepared, and a surface-protecting film (21) was obtained. The results are shown in Table 2.

[ comparative example 1]

As shown in table 1, a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive composition (C1) was produced in the same manner as in example 1 except that the amount of the isocyanate-based crosslinking 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, the amount of the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 part by weight in terms of solid content, and the amount of the polyol (trade name "sanni GP 250", Mn 250, manufactured by sanyo chemical industries, ltd.) was changed to 1.0 part by weight in terms of solid content, thereby obtaining a surface protective film (C1). The results are shown in Table 2.

[ comparative example 2]

As shown in table 1, a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive composition (C2) was produced in the same manner as in example 1 except that the amount of the isocyanate-based crosslinking 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, the amount of the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 part by weight in terms of solid content, and the amount of the polyol (trade name "sanni GP 250", Mn 250, manufactured by sanyo chemical industries, ltd.) was changed to 3.0 parts by weight in terms of solid content, thereby obtaining a surface protective film (C2). The results are shown in Table 2.

[ comparative example 3 ]

As shown in table 1, a pressure-sensitive adhesive layer composed of a pressure-sensitive adhesive composition (C3) was produced in the same manner as in example 1 except that the amount of the isocyanate-based crosslinking 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, the amount of the heat-resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, and the amount of the polyol (trade name "sanni GP 250", Mn 250, manufactured by sanyo chemical industries, ltd.) was changed to 5.0 parts by weight in terms of solid content, thereby obtaining a surface protective film (C3). The results are shown in Table 2.

[ comparative example 4 ]

As shown in table 1, an adhesive layer formed of an adhesive composition (C4) was prepared in The same manner as in example 1 except that The amount of The isocyanate crosslinking 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, The amount of The heat resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 part by weight in terms of solid content, The amount of The polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries co., ltd.) was changed to 1.0 part by weight in terms of solid content, and a fatty acid ester (trade name "SALACOS 816", The Nisshin oio Group, ltd.) was added in terms of solid content, thereby obtaining a surface protective film (C4). The results are shown in Table 2.

[ comparative example 5]

As shown in table 1, an adhesive layer formed of an adhesive composition (C5) was prepared in The same manner as in example 1 except that The amount of The isocyanate crosslinking 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, The amount of The heat resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 part by weight in terms of solid content, The amount of The polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries co., ltd.) was changed to 3.0 parts by weight in terms of solid content, and a fatty acid ester (trade name "SALACOS 816", The Nisshin oio Group, ltd.) was added in terms of solid content, thereby obtaining a surface protective film (C5). The results are shown in Table 2.

[ comparative example 6 ]

As shown in table 1, an adhesive layer formed of an adhesive composition (C6) was prepared in The same manner as in example 1 except that The amount of The isocyanate crosslinking 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, The amount of The heat resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, The amount of The polyol (trade name "sannii GP 250", Mn 250, manufactured by sanyo chemical industries co., ltd.) was changed to 5.0 parts by weight in terms of solid content, and a fatty acid ester (trade name "SALACOS 816", The Nisshin oio Group, ltd.) was added in terms of solid content, thereby obtaining a surface protective film (C6). The results are shown in Table 2.

[ comparative example 7 ]

As shown in Table 1, an adhesive layer comprising an adhesive composition (C7) was produced in the same manner as in example 1 except that the amount of the isocyanate crosslinking agent (trade name "CORONATE HL", manufactured by Nippon Polyurethane Industry Co., Ltd.) was changed to 16.0 parts by weight in terms of solid content, the amount of the heat resistant stabilizer (trade name "IRGANOX 1010", manufactured by BASF) was changed to 0.5 parts by weight in terms of solid content, the amount of the polyol (trade name "SANNIX GP 250", Mn. RTM. 250, manufactured by Sanyo chemical Co., Ltd.) was changed to 1.5 parts by weight in terms of solid content, the fluoropolymer (trade name "F-571", manufactured by DIC) was not used, and the hydroxyl group-containing silicone (trade name "X-22-4015", manufactured by shin chemical industries, Ltd.) was used in an amount of 0.05 parts by weight in terms of solid content, a surface protective film (C7) was obtained. The results are shown in Table 2.

[ Table 1]

[ Table 2]

[ examples 22 to 42 ]

The surface protection films (1) to (21) obtained in examples 1 to 21 were each peeled off from the separator, and the pressure-sensitive adhesive layer side was attached to a polarizing plate (product name "TEG 1465 DUHC" manufactured by hitto electrical corporation) as an optical member to obtain an optical member to which a surface protection film was attached.

[ examples 43 to 63 ]

The surface protection films (1) to (21) obtained in examples 1 to 21 were each separated from each other, and the pressure-sensitive adhesive layer side was bonded to a conductive film (product name "ELECRYSTA V270L-TFMP" manufactured by ritong electrical corporation) as an electronic component to obtain an electronic component having a surface protection film bonded thereto.

Industrial applicability

The surface protective film of the present invention can be used for any suitable purpose. The surface protective film of the present invention is preferably used in the fields of optical members and electronic members.

Description of the reference numerals

1 base material layer

2 adhesive layer

10 surface protective film

Claims (11)

1. A surface protective film having an adhesive layer,

the adhesive layer of the surface protective film is bonded to a glass plate and left at 23 ℃ for 30 minutes, and then the surface protective film is peeled from the glass plate at 23 ℃ at a peeling angle of 180 degrees and a peeling speed of 300 mm/minute, and the peeling force A is 0.005N/25mm to 0.50N/25mm when the peeling force is defined as peeling force A,

the pressure-sensitive adhesive layer of the surface protective film is bonded to a glass plate and left at 100 ℃ for 2 days, and then the surface protective film is peeled from the glass plate at 23 ℃ at a peeling angle of 180 degrees and a peeling speed of 300 mm/min, and when the peeling force at this peeling is defined as a peeling force B, the rate of increase P1 with time of the peeling force calculated as (peeling force B/peeling force A) × 100 is 200% or less.

2. The surface protection film according to claim 1, wherein when the storage modulus of the adhesive layer at 23 ℃ is X1 and the storage modulus of the surface protection film at 23 ℃ after being left at 80 ℃ for 7 days is Y1, the rate of change in storage modulus Q1 calculated as (storage modulus Y1/storage modulus X1) × 100 is 150% or less.

3. The surface protection film according to claim 1 or 2, wherein when the peeling force at a temperature of 23 ℃ after the pressure-sensitive adhesive layer of the surface protection film is bonded to a glass plate and left at the temperature of 23 ℃ for 7 days is 180 degrees at a peeling angle and a peeling speed of 300 mm/min, and the peeling force at this time is taken as the peeling force C, the peeling force increase rate P2 with time calculated as (peeling force C/peeling force a) × 100 is 160% or less.

4. The surface protection film according to any one of claims 1 to 3, wherein a residual adhesion rate to a glass plate at 23 ℃ is 50% or more.

5. The surface protection film according to any one of claims 1 to 4, wherein the adhesive constituting the adhesive layer is formed of an adhesive composition containing a heat-resistant stabilizer.

6. The surface protection film of claim 5, wherein the adhesive composition comprises: a base polymer, a low molecular weight polyol, and a silicone-based additive and/or a fluorine-based additive.

7. The surface protection film according to claim 6, wherein the silicone additive is at least 1 selected from the group consisting of a silicone bond-containing compound, a hydroxyl group-containing silicone compound, and a crosslinkable functional group-containing silicone compound.

8. The surface protection film according to claim 6, wherein the fluorine-based additive is at least 1 selected from a fluorine-containing compound, a fluorine-containing compound having a hydroxyl group, and a fluorine-containing compound having a crosslinkable functional group.

9. The surface protection film according to any one of claims 6 to 8, wherein the base polymer is at least 1 selected from a urethane prepolymer, a polyol, an acrylic resin, a rubber resin, and a silicone resin.

10. An optical member to which the surface protective film according to any one of claims 1 to 9 is attached.

11. An electronic component to which the surface protective film according to any one of claims 1 to 9 is attached.

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