JP2023084267A - Surface protective film - Google Patents

Abstract

To provide a surface protective film capable of exhibiting light peelability and suppressing the occurrence of black spots, and to provide an optical member and an electronic member each having the surface protective film attached thereto.SOLUTION: A surface protective film according to an embodiment of the present invention includes an adhesive layer, wherein the adhesive layer is composed of a urethane-based adhesive formed from a urethane-based adhesive composition, and the urethane-based adhesive composition contains a base polymer and a fluorine-based compound. The base polymer includes a urethane prepolymer, and the percentage of hydroxyl groups contained in the urethane-based adhesive composition is less than 30 mmol with respect to 100 g of the base polymer.SELECTED DRAWING: Figure 1

Description

The present invention relates to a surface protection film.

Surface protective films are attached to optical members and electronic members to prevent their surfaces from being scratched during processing, assembly, inspection, transportation, and the like. Such a surface protective film is peeled off from an optical member or an electronic member when surface protection is no longer necessary (Patent Document 1).

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

A pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive is known as a pressure-sensitive adhesive layer provided in a surface protective film. There are two methods for producing urethane-based adhesives: one-shot method, in which polyol and polyfunctional isocyanate are directly reacted without using urethane prepolymer to produce urethane adhesive, and urethane prepolymer and polyfunctional isocyanate. Two production methods are known, the prepolymer method in which urethane adhesives are produced by reaction.

In a surface protection film having an adhesive layer composed of a urethane-based adhesive, there is a technique for incorporating a fluorine-based compound into the adhesive composition forming the urethane-based adhesive in order to develop easy releasability. It is known (patent document 2).

However, when observing a conventional surface protection film provided with a pressure-sensitive adhesive layer composed of a urethane-based pressure-sensitive adhesive formed from a pressure-sensitive adhesive composition containing a fluorine-based compound, occurrence of black spots presumed to be caused by dents in the adhesive. It was observed. If such black spots occur frequently, not only may the quality of the surface protective film deteriorate, but also, for example, in the surface protective film laminated to optical members and electronic members, the inspectability may deteriorate. .

JP 2016-17109 A Japanese Patent No. 6896927

SUMMARY OF THE INVENTION An object of the present invention is to provide a surface protective film that exhibits easy releasability and suppresses the occurrence of black spots. Another object of the present invention is to provide an optical member and an electronic member to which such a surface protection film is adhered.

A surface protection film according to an embodiment of the present invention is
A surface protective film comprising an adhesive layer,
The pressure-sensitive adhesive layer is composed of a urethane-based pressure-sensitive adhesive formed from a urethane-based pressure-sensitive adhesive composition,
The urethane pressure-sensitive adhesive composition contains a base polymer and a fluorine-based compound,
the base polymer comprises a urethane prepolymer;
The proportion of hydroxyl groups contained in the urethane pressure-sensitive adhesive composition is less than 30 mmol relative to 100 g of the base polymer.

（一般式（１）中、Ｒ^１は、水素原子、炭素数１～４のアルキル基、および、炭素数１～６のヒドロキシアルキル基からなる群から選択される１種を表す。複数のＲ^１は、互いに同一であってもよく互いに異なっていてもよい。ｎは１～４の整数を表す。ｍは１～２００の整数を表す。） In one embodiment, the base polymer contains a polyoxyalkylene structure represented by general formula (1).

(In general formula (1), R ¹ represents one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a hydroxyalkyl group having 1 to 6 carbon atoms. Multiple R ¹ may be the same or different, n represents an integer of 1 to 4, and m represents an integer of 1 to 200.)

In one embodiment, the urethane prepolymer contains a polyoxyalkylene structure represented by the general formula (1).

In one embodiment the base polymer comprises a polyol and the polyol is not a urethane prepolymer.

（一般式（１）中、Ｒ^１は、水素原子、炭素数１～４のアルキル基、および、炭素数１～６のヒドロキシアルキル基からなる群から選択される１種を表す。複数のＲ^１は、互いに同一であってもよく互いに異なっていてもよい。ｎは１～４の整数を表す。ｍは１～２００の整数を表す。） In one embodiment, the polyol contains a polyoxyalkylene structure represented by general formula (1).

(In general formula (1), R ¹ represents one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a hydroxyalkyl group having 1 to 6 carbon atoms. Multiple R ¹ may be the same or different, n represents an integer of 1 to 4, and m represents an integer of 1 to 200.)

In one embodiment, the content ratio of the urethane prepolymer and the polyol in the urethane pressure-sensitive adhesive composition is urethane prepolymer:polyol=70:30 to 100:0 by weight.

In one embodiment, the adhesive layer has a haze of 3.5% or less.

In one embodiment, a 0.1% propylene glycol monomethyl ether solution of the fluorine compound has a surface tension of 23 mN/m or more.

In one embodiment, the urethane pressure-sensitive adhesive composition contains 0.05 parts by weight or more of the ionic compound with respect to 100 parts by weight of the base polymer.

An optical member according to an embodiment of the present invention has a surface protective film according to an embodiment of the present invention adhered thereto.

An electronic member according to an embodiment of the present invention is attached with a surface protective film according to an embodiment of the present invention.

ADVANTAGE OF THE INVENTION According to this invention, the surface protection film which can express easy peelability and can suppress generation|occurrence|production of a black spot can be provided. Further, it is possible to provide an optical member and an electronic member to which such a surface protective film is adhered.

1 is a schematic cross-sectional view of a surface protection film according to a preferred embodiment of the invention; FIG.

<<<<<1. Surface protection film>>>>>>
A surface protection film according to an embodiment of the present invention includes an adhesive layer. A surface protection film according to an embodiment of the present invention preferably includes a substrate layer and an adhesive layer.

The base material layer may consist of only one layer, or may consist of two or more layers.

The pressure-sensitive adhesive layer may consist of only one layer, or may consist of two or more layers.

Any appropriate release liner may be adhered to the adhesive surface (sometimes referred to as the adhesive surface) side of the adhesive layer as long as the effects of the present invention are not impaired.

Release liners include, for example, a release liner in which the surface of a base material (liner base material) such as paper or plastic film is treated with silicone, or a base material (liner base material) such as paper or plastic film whose surface is coated with a polyolefin resin. Included are laminated release liners.

Any appropriate plastic film can be employed as the plastic film as the base material of the release liner as long as the effects of the present invention are not impaired. Examples of such plastic films include polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, vinyl chloride copolymer films, polyethylene terephthalate films, polybutylene terephthalate films, and polyurethane films. , and ethylene-vinyl acetate copolymer films.

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

When the surface protection film according to the embodiment of the present invention includes a substrate layer and an adhesive layer, the surface of the substrate layer opposite to the adhesive layer is intended to form a roll that can be easily unwound. For example, a release treatment is performed by adding a fatty acid amide, polyethyleneimine, long-chain alkyl-based additive, etc. to the base material layer, or any appropriate release agent such as silicone-based, long-chain alkyl-based, fluorine-based, etc. A coat layer made of an agent can be provided.

The surface protective film according to the embodiment of the present invention may have any other appropriate layer within the range that does not impair the effects of the present invention.

FIG. 1 is a schematic cross-sectional view of a surface protection film according to a preferred embodiment of the invention. As shown in FIG. 1, a surface protective film 10 according to a preferred embodiment of the present invention comprises a substrate layer 1 and an adhesive layer 2, and the substrate layer 1 and the adhesive layer 2 are directly laminated.

The thickness of the surface protective film according to the embodiment of the present invention can be set to any appropriate thickness depending on the application. Typically, it is preferably 10 μm to 300 μm, more preferably 15 μm to 250 μm, even more preferably 20 μm to 200 μm, and particularly preferably 25 μm to 170 μm.

The surface protective film according to the embodiment of the present invention can preferably exhibit light releasability. The surface protective film of the present invention has a peel strength when the pressure-sensitive adhesive layer it contains is attached to a glass plate, and after 30 minutes at 23 ° C., the film is peeled from the glass plate at a peel angle of 180 degrees and a peel speed of 300 mm / min. is preferably 0.5 gf/25 mm to 5.0 gf/25 mm, more preferably 0.5 gf/25 mm to 4.0 gf/25 mm, still more preferably 0.5 gf/25 mm to 3.0 gf/25 mm It is particularly preferably 0.5 gf/25 mm to 2.5 gf/25 mm, most preferably 0.5 gf/25 mm to 2.0 gf/25 mm. If the peel force is within the above range, the surface protective film according to the embodiment of the present invention can exhibit excellent easy peelability. The details of the method for measuring the peel force will be described later.

Surface protective films according to embodiments of the present invention can preferably achieve low haze. The haze of the pressure-sensitive adhesive layer contained in the surface protective film of the present invention is preferably 4.0% or less, more preferably 3.0% or less, and still more preferably 2.0% or less, It is particularly preferably 1.5% or less, most preferably 1.0% or less. If the haze is within the above range, the surface protective film according to the embodiment of the present invention can achieve excellent low haze and, for example, exhibit excellent testability. Details of the haze measuring method will be described later.

The surface protective film according to the embodiment of the present invention is prepared by attaching the pressure-sensitive adhesive layer it contains to a glass plate, leaving it for one day in an environment of 23 ° C. and 50% RH, and peeling it from the glass plate at a peeling angle of 150 degrees. The stripping electrostatic voltage when stripped at a stripping speed of 30 m/min is preferably 15 kV or less, more preferably 10 kV or less, still more preferably 5 kV or less, particularly preferably 2 kV or less, and most preferably 1 kV. It is below. If the peeling electrification voltage is within the above range, the surface protective film according to the embodiment of the present invention can effectively prevent electrification during peeling. The details of the method for measuring the separation electrification voltage will be described later.

<<<1-1. Adhesive layer≫≫
The adhesive layer is composed of a urethane-based adhesive. A urethane-based pressure-sensitive adhesive is formed from a urethane-based pressure-sensitive adhesive composition. That is, the urethane-based pressure-sensitive adhesive formed from the urethane-based pressure-sensitive adhesive composition forms a layer shape to form the pressure-sensitive adhesive layer.

The thickness of the pressure-sensitive adhesive layer can be set to any suitable thickness depending on the application. Typically, it is preferably 1 μm to 150 μm, more preferably 5 μm to 130 μm, even more preferably 10 μm to 110 μm, and particularly preferably 20 μm to 100 μm.

A urethane pressure-sensitive adhesive composition contains a base polymer and a fluorine compound. Only one type of base polymer may be used, or two or more types may be used. Only one type of fluorine-based compound may be used, or two or more types may be used.

Base polymers include urethane prepolymers. Details of the urethane prepolymer will be described later.

The base polymer may contain polyols. Details of the polyol will be described later. In addition, the polyol in this invention is not a urethane prepolymer so that it may mention later.

Embodiments of the base polymer in the present invention are preferably
(A) an embodiment containing a urethane prepolymer and no polyol;
or,
(B) an embodiment comprising both a urethane prepolymer and a polyol;
is.

Embodiments of the base polymer in the present invention are more preferably
(a) an embodiment comprising a urethane prepolymer;
or,
(b) an embodiment comprising a urethane prepolymer and a polyol;
is.

The content of the base polymer in the urethane-based pressure-sensitive adhesive composition is preferably 50% by weight to 99.99% by weight, more preferably 70% by weight to 99.99% by weight, from the viewpoint that the effects of the present invention can be further exhibited. 99% by weight, more preferably 90% to 99.99% by weight, particularly preferably 95% to 99.99% by weight. By adjusting the content of the base polymer in the urethane-based pressure-sensitive adhesive composition within the above range, the surface protective film of the present invention can further exhibit the effects of the present invention.

The urethane pressure-sensitive adhesive composition has a hydroxyl group content of less than 30 mmol, preferably 5 mmol to 28 mmol, more preferably 5 mmol to 25 mmol, still more preferably 5 mmol to 22 mmol, relative to 100 g of the base polymer. and particularly preferably 5 mmol to 20 mmol. By setting the ratio of hydroxyl groups contained in the urethane pressure-sensitive adhesive composition within the above range with respect to 100 g of the base polymer, the effects of the present invention can be exhibited.

In completing the present invention, the present inventors conducted various studies on how to suppress the occurrence of black spots as a problem. As a result, the cause of black spots is that the fluorine-based compound acts as a surfactant around the air bubbles generated in the process of forming the adhesive to form stable micelles, which eventually become the adhesive layer. It was thought that the adhesive dents might occur due to the air bubbles. Therefore, the present inventors thought that if the formation of the above micelles could be suppressed, the occurrence of black spots could be suppressed. Specifically, attention was paid to the compatibility between the urethane prepolymer and the optional polyol) and the fluorine-based compound. Then, as a result of repeated studies from the viewpoint of adjusting the compatibility between the base polymer and the fluorine-based compound, as described above, the ratio of the hydroxyl groups contained in the urethane-based pressure-sensitive adhesive composition was within the above range with respect to 100 g of the base polymer. The inventors have found that by doing so, the occurrence of black spots can be effectively suppressed.

A urethane-based pressure-sensitive adhesive may be defined as being formed from a urethane-based pressure-sensitive adhesive composition. This is because the urethane-based pressure-sensitive adhesive becomes a urethane-based pressure-sensitive adhesive when the urethane-based pressure-sensitive adhesive composition undergoes a cross-linking reaction by heating, ultraviolet irradiation, or the like. However, due to the fact that it is impossible and almost impractical (“impossible/impractical circumstances”), urethane It is a valid specification of the system adhesive as a "thing".

As a method for forming a urethane-based pressure-sensitive adhesive from a urethane-based pressure-sensitive adhesive composition, any appropriate forming method can be adopted as long as the effects of the present invention are not impaired. As such a forming method, for example, the urethane pressure-sensitive adhesive composition is directly applied to any appropriate base film (for example, the base layer in the surface protection film according to the embodiment of the present invention) and dried or cured. method (direct method), a urethane-based pressure-sensitive adhesive layer is formed on the surface (release surface) of a release liner by applying a urethane-based pressure-sensitive adhesive composition to the surface (release surface) of the release liner and drying or curing the composition onto a substrate film (e.g., this method). A method (transfer method) of transferring the urethane-based pressure-sensitive adhesive layer to the substrate layer of the surface protective film according to the embodiment of the invention) can be mentioned.

As a method for applying the urethane-based pressure-sensitive adhesive composition, any appropriate application method can be adopted as long as the effects of the present invention are not impaired. Examples of such coating methods include roll coating, gravure roll coating, reverse roll coating, kiss roll coating, dip roll coating, bar coating, roll brushing, spray coating, knife coating, Air knife coating, comma coating, direct coating, die coating and roll brush coating can be used.

Drying of the urethane pressure-sensitive adhesive composition can be performed under heating (for example, by heating to about 60° C. to 150° C.), if necessary.

As means for curing the urethane-based pressure-sensitive adhesive composition, any appropriate curing means can be adopted as long as the effects of the present invention are not impaired. Examples of such curing means include ultraviolet irradiation, laser beam irradiation, α-ray irradiation, β-ray irradiation, γ-ray irradiation, X-ray irradiation, and electron beam irradiation.

The base polymer (typically at least one selected from urethane prepolymers and polyols described later) preferably contains a polyoxyalkylene structure represented by general formula (1). By including the polyoxyalkylene structure represented by the general formula (1) in the base polymer, it is possible to exhibit more light release properties. In addition, it can be confirmed by any appropriate method that the base polymer contains the polyoxyalkylene structure represented by the general formula (1). Examples of such methods include NMR measurement and IR measurement.

In general formula (1), R ¹ represents one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a hydroxyalkyl group having 1 to 6 carbon atoms. In addition, a plurality of R ¹ may be the same as each other or may be different from each other.

In the general formula (1), when R ¹ is an alkyl group having 1 to 4 carbon atoms, the alkyl group includes, for example, a linear alkyl group such as a methyl group, an ethyl group, and an n-propyl group; an isopropyl group; , an isobutyl group, a branched alkyl group such as a 2-ethylhexyl group;

In general formula (1), when R ¹ is a hydroxyalkyl group having 1 to 6 carbon atoms, the hydroxyalkyl group includes, for example, a hydroxymethyl group, a 2-hydroxyethyl group, a 2-methyl-1,4- A hydroxybutyl group is mentioned.

R ¹ in general formula (1) is preferably one selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 4 carbon atoms, more preferably a group consisting of a hydrogen atom and a methyl group. and more preferably a hydrogen atom.

In the general formula (1), n is the repeating number of structural units and represents an integer of 1-4. n is preferably an integer of 1 to 3, more preferably 1 or 2, and still more preferably 2, in order to more express the effects of the present invention.

In the general formula (1), m is the repeating number of structural units and represents an integer of 1-200. m is preferably from 10 to 100, more preferably from 15 to 75, and even more preferably from 20 to 50, in order to more express the effects of the present invention.

The base polymer (typically at least one selected from urethane prepolymers and polyols described below) preferably contains a polyoxyalkylene structure represented by general formula (2). By including the polyoxyalkylene structure represented by the general formula (2) in the base polymer, it is possible to exhibit more light release properties. In addition, it can be confirmed by any appropriate method that the base polymer contains the polyoxyalkylene structure represented by the general formula (2). Examples of such methods include NMR measurement and IR measurement.

In general formula (2), R ² represents one selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 4 carbon atoms. In addition, a plurality of R ² may be the same as each other or may be different from each other.

In the general formula (2), when R ² is an alkyl group having 1 to 4 carbon atoms, the alkyl group includes, for example, a linear alkyl group such as a methyl group, an ethyl group, and an n-propyl group; an isopropyl group; , a branched alkyl group such as an isobutyl group;

R ² in general formula (2) is preferably one selected from the group consisting of a hydrogen atom and a methyl group, more preferably a hydrogen atom.

In the general formula (2), p is the number of repeating structural units and represents an integer of 1-300. p is preferably an integer of 10 to 250, more preferably an integer of 20 to 200, and even more preferably an integer of 30 to 150, so that the effects of the present invention can be more expressed.

<<1-1-1. Urethane prepolymer≫
Base polymers include urethane prepolymers.

Only one type of urethane prepolymer may be used, or two or more types may be used.

The number-average molecular weight Mn of the urethane prepolymer is preferably 1,000 to 100,000 in order to exhibit the effects of the present invention.

The base polymer may contain a polyol, as described below. However, the polyol in the present invention is not a urethane prepolymer. That is, the urethane pressure-sensitive adhesive composition may contain a polyol that is not a urethane prepolymer. The reason why the polyol in this specification is defined as not a urethane prepolymer is as follows. That is, the urethane prepolymer in the present specification is a "urethane prepolymer" (urethane prepolymer used in the prepolymer method) generally called by those skilled in the art in the production of urethane resin, and a "polyol" (used in the one-shot method). Although different from polyols), urethane prepolymers also have a plurality of hydroxyl groups, so that urethane prepolymers and polyols are clearly distinguished in the present specification.

The content ratio of the urethane prepolymer and the polyol in the base polymer is preferably urethane prepolymer:polyol = 50:50 to 100:0 in terms of the weight ratio in terms of more expressing the effects of the present invention. Preferably, urethane prepolymer: polyol = 55:45 to 100:0, more preferably urethane prepolymer: polyol = 60:40 to 100:0, particularly preferably urethane prepolymer: polyol = 70 :30 to 100:0, most preferably urethane prepolymer:polyol=80:20 to 100:0.

The content of the urethane prepolymer in the urethane pressure-sensitive adhesive composition is preferably 80% to 99.99% by weight, more preferably 85% to 99.99% by weight, when the base polymer does not contain a polyol. %, more preferably 90 wt % to 99.99 wt %, particularly preferably 95 wt % to 99.99 wt %. When the base polymer does not contain a polyol, by adjusting the content of the urethane prepolymer in the urethane-based pressure-sensitive adhesive composition within the above range, the surface protective film of the present invention can further exhibit the effects of the present invention. .

The content of the urethane prepolymer in the urethane pressure-sensitive adhesive composition is preferably 40% to 99.98% by weight, more preferably 42% to 99.98% by weight when the base polymer contains a polyol. , more preferably 44% to 99.98% by weight, particularly preferably 46% to 99.98% by weight. When the base polymer contains a polyol, the surface protective film of the present invention can exhibit the effects of the present invention more by adjusting the content of the urethane prepolymer in the urethane pressure-sensitive adhesive composition within the above range.

The urethane prepolymer preferably contains a polyoxyalkylene structure represented by general formula (1) above. When the urethane prepolymer contains the polyoxyalkylene structure represented by the general formula (1), it is possible to exhibit more light release properties.

The urethane prepolymer preferably contains a polyoxyalkylene structure represented by general formula (2) above. When the urethane prepolymer contains the polyoxyalkylene structure represented by the general formula (2), it is possible to exhibit more light release properties.

As a specific preferred embodiment of the urethane prepolymer,
<Embodiment a> A urethane prepolymer (U1) containing a polyoxyalkylene structure represented by the above general formula (1) and not containing a polyoxyalkylene structure represented by the above general formula (2),
<Embodiment b> A urethane prepolymer (U2) containing both a polyoxyalkylene structure represented by the above general formula (1) and a polyoxyalkylene structure represented by the above general formula (2),
<Embodiment c> A urethane prepolymer (U3) containing a polyoxyalkylene structure represented by the above general formula (2) but not containing a polyoxyalkylene structure represented by the above general formula (2),
are mentioned.

The content ratio of the polyoxyalkylene structure represented by the above general formula (1) and the polyoxyalkylene structure represented by the above general formula (2) in the urethane prepolymer (U2) does not impair the effects of the present invention. Any appropriate content ratio can be adopted within the range. Such a content ratio is represented by the general formula (1) with respect to the total amount of the polyoxyalkylene structure represented by the general formula (1) and the polyoxyalkylene structure represented by the general formula (2). The content of the polyoxyalkylene structure is preferably 50% to 99.9% by weight, more preferably 60% to 99% by weight, still more preferably 65% to 98% by weight. , particularly preferably 70% to 95% by weight. Content of the polyoxyalkylene structure represented by the general formula (1) with respect to the total amount of the polyoxyalkylene structure represented by the general formula (1) and the polyoxyalkylene structure represented by the general formula (2) By adjusting the ratio within the above range, the surface protective film of the present invention can exhibit the effects of the present invention more.

The urethane prepolymer is typically a polyurethane polyol, preferably at least one selected from polyether polyols and polyester polyols, in the presence or absence of a catalyst, reacting with the polyfunctional isocyanate compound (A). Let it be obtained.

Only one kind of polyether polyol may be used, or two or more kinds thereof may be used.

Only one kind of polyester polyol may be used, or two or more kinds thereof may be used.

A commercially available urethane prepolymer may be employed as the urethane prepolymer.

Any appropriate polyether polyol can be used as the polyether polyol as long as the effects of the present invention are not impaired. Examples of such polyether polyols include water, propylene glycol, ethylene glycol, glycerin, trimethylolpropane, and other low-molecular-weight polyols as initiators, and ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, and other oxirane compounds. Examples include polyether polyols obtained by polymerization. Examples of such polyether polyols include polypropylene glycol (also referred to as polyoxypropylene glycol), polyethylene glycol (also referred to as polyoxyethylene glycol), polytetramethylene glycol (also referred to as polyoxytetramethylene glycol), and polyoxypropylene. Examples include polyether polyols having two or more functional groups such as triols, and modified products thereof.

Part of the polyether polyol, if necessary, for example, glycols such as ethylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, glycerin, trimethylolpropane, pentaerythritol, and ethylenediamine , N-aminoethylethanolamine, isophoronediamine, and xylylenediamine.

The number average molecular weight Mn of the polyether polyol is preferably 500-5000, more preferably 1000-4500, and even more preferably 1000-4000. If the number average molecular weight is less than 500, the reactivity becomes high and gelation may easily occur. If the number-average molecular weight exceeds 5,000, the reactivity may become low, and the cohesive strength of the polyurethane polyol itself may become small.

As the polyether polyol, only a bifunctional polyether polyol may be used, or a polyether polyol having a number average molecular weight of 500 to 5000 and at least 3 or more hydroxyl groups in one molecule may be used. Part or all may be used. When a polyether polyol having an average molecular weight of 500 to 5000 and having at least 3 or more hydroxyl groups in one molecule is partially or wholly used as the polyether polyol, the adhesive strength and removability are well balanced. obtain. In such a polyether polyol, if the number average molecular weight is less than 500, the reactivity becomes high and there is a possibility that gelation is likely to occur. Moreover, in such a polyether polyol, if the number average molecular weight exceeds 5,000, the reactivity may be lowered, and furthermore, the cohesive strength of the urethane prepolymer itself may be lowered.

Any appropriate polyester polyol can be used as the polyester polyol as long as the effects of the present invention are not impaired. Examples of such polyester polyols include polyester polyols obtained by reacting an acid component and a glycol component. Examples of acid components include terephthalic acid, adipic acid, azelaic acid, sebacic acid, phthalic anhydride, isophthalic acid, and trimellitic acid. Examples of glycol components include ethylene glycol, propylene glycol, diethylene glycol, butylene glycol, 1,6-hexane glycol, 3-methyl-1,5-pentanediol, 3,3′-dimethylolheptane, polyoxyethylene glycol, Examples include polyoxypropylene glycol, 1,4-butanediol, neopentyl glycol, butylethylpentanediol, and polyol components such as glycerin, trimethylolpropane, and pentaerythritol. Examples of polyester polyols include, in addition to these, polyester polyols obtained by ring-opening polymerization of lactones such as polycaprolactone, poly(β-methyl-γ-valerolactone), and polyvalerolactone.

The number average molecular weight Mn of the polyester polyol is preferably 500-5000. If the number average molecular weight is less than 500, the reactivity becomes high and gelation may easily occur. If the number average molecular weight exceeds 5,000, the reactivity may become low, and furthermore, the cohesive strength of the polyurethane polyol itself may become small. The amount of the polyester polyol used is preferably 1 mol % to 90 mol % of the total amount of the polyether polyol and the polyester polyol as raw materials for the urethane prepolymer, from the point of view that the effects of the present invention can be further expressed. , more preferably 3 mol % to 70 mol %, still more preferably 5 mol % to 50 mol %, and particularly preferably 7 mol % to 30 mol %.

When the urethane prepolymer (U1) is employed as the urethane prepolymer, the polyol (at least one selected from polyether polyols and polyester polyols) as a raw material for the urethane prepolymer is preferably represented by the above general formula (1). It contains a polyether polyol (PO1) containing a polyoxyalkylene structure represented by the general formula (2) and does not contain a polyether polyol (PO2) containing a polyoxyalkylene structure represented by the general formula (2). In this case, the content of the polyether polyol (PO1) in the total amount of polyols (at least one selected from polyether polyols and polyester polyols) as a raw material for the urethane prepolymer is such that the effects of the present invention can be expressed more effectively. , preferably 50 wt% to 100 wt%, more preferably 70 wt% to 100 wt%, still more preferably 90 wt% to 100 wt%, most preferably 95 wt% to 100 wt% is.

When the urethane prepolymer (U2) is employed as the urethane prepolymer, the polyol (at least one selected from polyether polyols and polyester polyols) as a raw material for the urethane prepolymer is preferably represented by the above general formula (1). and a polyether polyol (PO2) containing a polyoxyalkylene structure represented by the above general formula (2). In this case, the use ratio of the polyether polyol (PO1) and the polyether polyol (PO2) is the total amount of the polyether polyol (PO1) and the polyether polyol (PO2) from the point of view that the effects of the present invention can be more expressed. The amount of polyether polyol (PO1) used for Especially preferred is 75% to 85% by weight.

When the urethane prepolymer (U3) is employed as the urethane prepolymer, the polyol (at least one selected from polyether polyols and polyester polyols) as a raw material for the urethane prepolymer is preferably represented by the above general formula (2). It contains a polyether polyol (PO2) containing a polyoxyalkylene structure represented by the general formula (1) and does not contain a polyether polyol (PO1) containing a polyoxyalkylene structure represented by the general formula (1). In this case, the content of polyether polyol (PO2) in the total amount of polyols (at least one selected from polyether polyols and polyester polyols) as a raw material for the urethane prepolymer is such that the effect of the present invention can be expressed more effectively. , preferably 50 wt% to 100 wt%, more preferably 60 wt% to 100 wt%, still more preferably 70 wt% to 100 wt%, most preferably 80 wt% to 100 wt% is.

Examples of polyether polyol (PO1) include polytetramethylene glycol (also referred to as polyoxytetramethylene glycol) and modified products thereof.

The number average molecular weight Mn of the polyether polyol (PO1) is preferably 1,000 to 5,000, more preferably 1,500 to 4,500, and still more preferably 2,000 to 4,000 from the viewpoint that the effects of the present invention can be further exhibited. , particularly preferably 2200-3800, most preferably 2500-3500.

Polyether polyols (PO2) include, for example, polypropylene glycol (also referred to as polyoxypropylene glycol), polyethylene glycol (also referred to as polyoxyethylene glycol), polyoxypropylene triol, and modified products thereof.

The number average molecular weight Mn of the polyether polyol (PO2) is preferably from 500 to 4500, more preferably from 600 to 4000, and even more preferably from 700 to 3500, from the viewpoint that the effects of the present invention can be further expressed. , particularly preferably 800-3000, most preferably 900-2500.

When polyether polyol (PO2) is used as a raw material for the urethane prepolymer (U3), the effect of the present invention can be further expressed by using a polyether polyol (PO2) having a number average molecular weight Mn of 1500 or more and a number average molecular weight A polyether polyol (PO2) having an Mn of less than 1,500 is preferably used in combination. In this case, the content of the polyether polyol (PO2) having a number average molecular weight Mn of 1500 or more in the total amount of the polyether polyol (PO2) employed as the raw material of the urethane prepolymer (U3) is preferably 10% by weight to 90% by weight. % by weight, more preferably 20% to 80% by weight, still more preferably 30% to 70% by weight, and most preferably 40% to 60% by weight.

Any appropriate polyfunctional isocyanate compound can be used as the polyfunctional isocyanate compound (A) as long as the effects of the present invention are not impaired. Examples of such polyfunctional isocyanate compounds (A) include aromatic polyisocyanates, aliphatic polyisocyanates, araliphatic polyisocyanates, and alicyclic polyisocyanates.

Examples of aromatic polyisocyanates include 1,3-phenylene diisocyanate, 4,4'-diphenyldiisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6 - tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanatotoluene, 1,3,5-triisocyanatobenzene, dianisidine diisocyanate, 4,4'- diphenyl ether diisocyanate, 4,4′,4″-triphenylmethane triisocyanate, 1,5-naphthalene diisocyanate, and xylylene diisocyanate.

Examples of aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate may be mentioned.

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

Examples of alicyclic polyisocyanates include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2 ,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4′-methylenebis(cyclohexyl isocyanate), 1,4-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, isophorone diisocyanate , hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated tetramethylxylylene diisocyanate.

Examples of the polyfunctional isocyanate compound (A) include trimethylolpropane adducts, water-reacted biuret forms, and trimers having an isocyanurate ring of various polyfunctional isocyanate compounds as described above. Moreover, these can be used together.

Any appropriate catalyst can be used as the catalyst that can be used in producing the urethane prepolymer as long as the effects of the present invention are not impaired. Examples of such catalysts include tertiary amine compounds and organometallic compounds. Only one kind of catalyst may be used, or two or more kinds thereof may be used.

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

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

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

Examples of non-tin compounds include titanium compounds such as dibutyl titanium dichloride, tetrabutyl titanate, and butoxy titanium trichloride; lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate. iron-based compounds such as iron 2-ethylhexanoate and iron acetylacetonate; cobalt-based compounds such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc-based compounds such as zinc naphthenate and zinc 2-ethylhexanoate; zirconium-based compounds such as zirconium naphthenate;

As the catalyst, a tin-based compound is preferably used from the viewpoint of exhibiting the effects of the present invention, while a non-tin-based compound is preferably used from the viewpoint of environmental measures.

When a catalyst is used in producing the urethane prepolymer, the amount of the catalyst used is the polyol (at least one selected from polyether polyol and polyester polyol) and the polyfunctional isocyanate compound (A) as raw materials for the urethane prepolymer. is preferably 0.01% to 1.0% by weight based on the total amount of

If a catalyst is used in making the urethane prepolymer, the reaction temperature is preferably below 100°C, more preferably between 85°C and 95°C. If the temperature is 100° C. or higher, it may become difficult to control the reaction rate and the crosslinked structure, and it may become difficult to obtain a urethane prepolymer having a predetermined molecular weight.

A catalyst may not be used when producing the urethane prepolymer. In that case, the reaction temperature is preferably 100° C. or higher, more preferably 110° C. or higher. Moreover, when obtaining a urethane prepolymer in the absence of a catalyst, it is preferable to carry out the reaction for 3 hours or longer.

Methods for producing a urethane prepolymer include, for example, 1) a method in which the total amount of a polyol (at least one selected from polyether polyols and polyester polyols), a catalyst, and a polyfunctional isocyanate compound (A) as raw materials is charged into a reactor; 2) A method of adding a polyol (at least one selected from polyether polyol and polyester polyol) as a raw material and a catalyst into a reactor and then adding the polyfunctional isocyanate compound (A) dropwise. As a method for producing a urethane prepolymer, method 2) is preferable in terms of controlling the reaction.

Any suitable solvent can be used in the production of the urethane prepolymer as long as the effects of the present invention are not impaired. Such solvents include, for example, methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone. Among these solvents, ethyl acetate and toluene are preferred.

<<1-1-2. Polyol≫
The base polymer may contain polyols. However, as mentioned above, the polyol in the present invention is not a urethane prepolymer.

When the base polymer contains a polyol, the content of the polyol in the urethane pressure-sensitive adhesive composition is preferably 0.02 wt% to 80 wt%, more preferably 0.02 wt% to 70 wt%. , more preferably 0.02% to 60% by weight, and particularly preferably 0.02% to 55% by weight. When the base polymer contains a polyol, the surface protective film of the present invention can further exhibit the effects of the present invention by adjusting the content of the polyol in the urethane pressure-sensitive adhesive composition within the above range.

Examples of polyols include polyester polyols, polyether polyols, polycaprolactone polyols, polycarbonate polyols, and castor oil-based polyols. Polyols are more preferably polyester polyols and polyether polyols.

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

Polyol components include, for example, 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, polypropylene glycol.

Examples of acid components 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, 4,4'-biphenyldicarboxylic acid , and acid anhydrides thereof.

Examples of polyether polyols include water, low-molecular-weight polyols (propylene glycol, ethylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc.), bisphenols (bisphenol A, etc.), dihydroxybenzenes (catechol, resorcinol, hydroquinone, etc.). is used as an initiator, polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide. Specific examples include polyethylene glycol, polypropylene glycol, polytetramethylene glycol and the like.

Examples of polycaprolactone polyols include caprolactone-based polyester diols obtained by ring-opening polymerization of cyclic ester monomers such as ε-caprolactone and σ-valerolactone.

Polycarbonate polyols include, for example, polycarbonate polyols obtained by subjecting the above polyol component and phosgene to a polycondensation reaction; Polycarbonate polyols obtained by subjecting propylene carbonate, diphenyl carbonate, dibenzyl carbonate, and other carbonic acid diesters to transesterification condensation; Copolymerized polycarbonate polyols obtained by using two or more of the above polyol components in combination; Various polycarbonate polyols above and carboxyl group-containing polyols Polycarbonate polyol obtained by esterifying a compound; Polycarbonate polyol obtained by etherifying the above various polycarbonate polyols and a hydroxyl group-containing compound; Obtained by transesterifying the above various polycarbonate polyols and an ester compound. Polycarbonate polyols; Polycarbonate polyols obtained by transesterification of various polycarbonate polyols and hydroxyl group-containing compounds; Polyester-based polycarbonate polyols obtained by polycondensation reaction of various polycarbonate polyols and dicarboxylic acid compounds; Various polycarbonate polyols and a copolymerized polyether-based polycarbonate polyol obtained by copolymerizing an alkylene oxide;

Examples of castor oil-based polyols include castor oil-based polyols obtained by reacting castor oil fatty acids with the above polyol components. Specific examples include castor oil-based polyols obtained by reacting castor oil fatty acids with polypropylene glycol.

As the polyol, a polyether polyol (PO1) containing a polyoxyalkylene structure represented by the general formula (1) may be employed.

Examples of the polyether polyol (PO1) include polytetramethylene glycol (also referred to as polyoxytetramethylene glycol) and modified products thereof, as described above.

The polyol preferably contains a first polyol having a number average molecular weight Mn of 5,000 to 20,000 and a second polyol having a number average molecular weight Mn of 300 to 4,999, in order to further develop the effects of the present invention.

1st polyol A1 may be sufficient as 1 type, and may be 2 or more types.

The number of second polyols A2 may be one, or two or more.

The content of the total amount of the first polyol and the second polyol in the polyol is preferably 80% by weight to 100% by weight, more preferably 90% by weight, from the viewpoint that the effects of the present invention can be further expressed. ~100% by weight, more preferably 95% to 100% by weight, particularly preferably 98% to 100% by weight, most preferably substantially 100% by weight.

The number average molecular weight Mn of the first polyol is 5,000 to 20,000, preferably 6,000 to 18,000, more preferably 7,000 to 16,000, still more preferably 8,000 to 15,000, and particularly preferably 9,000 to 14,000. be. If the number average molecular weight Mn of the first polyol is within the above range, the effects of the present invention can be exhibited more effectively.

The number average molecular weight Mn of the second polyol is 300 to 4999, preferably 500 to 4500, more preferably 1000 to 4000, still more preferably 1500 to 3800, particularly preferably 2000 to 3500. be. If the number average molecular weight Mn of the second polyol is within the above range, the effects of the present invention can be exhibited more effectively.

The weight ratio of the first polyol and the second polyol is preferably 0.7 ≤ (first polyol/second polyol) ≤ 3.5, more preferably 1.0 ≤ (first polyol) polyol/second polyol)≦3.0, more preferably 1.1≦(first polyol/second polyol)≦2.5, and particularly preferably 1.2≦(first polyol) polyol/second polyol)≦2.0. If the weight ratio of the first polyol and the second polyol is within the above range, the surface protective film according to the embodiment of the present invention can achieve excellent low haze and, for example, can exhibit excellent inspection properties. .

The number of OH groups that the first polyol has is preferably 3 to 6, more preferably 3 to 5, and still more preferably, from the viewpoint that the effects of the present invention can be more expressed. is 3 to 4, particularly preferably 3.

The first polyol preferably contains 50% to 100% by weight, more preferably 70% to 100% by weight, of a triol having 3 OH groups, in order to further express the effects of the present invention. %, more preferably 90% to 100% by weight, particularly preferably 95% to 100% by weight, most preferably substantially 100% by weight.

The second polyol preferably has 3 to 6 OH groups, more preferably 3 to 5, still more preferably 3 to 5 OH groups, in that the effects of the present invention can be more expressed. is 3 to 4, particularly preferably 3.

The second polyol preferably contains 50% to 100% by weight, more preferably 70% to 100% by weight, of a triol having 3 OH groups in order to further express the effects of the present invention. %, more preferably 90% to 100% by weight, particularly preferably 95% to 100% by weight, most preferably substantially 100% by weight.

<<1-1-3. Polyfunctional isocyanate compound (B)>>
The urethane pressure-sensitive adhesive composition preferably contains a polyfunctional isocyanate compound (B). When the urethane-based pressure-sensitive adhesive composition contains the polyfunctional isocyanate compound (B), a cross-linking reaction occurs between the urethane prepolymer contained in the urethane-based pressure-sensitive adhesive composition and the polyol that may be included as an optional component, resulting in a urethane-based pressure-sensitive adhesive. can form an agent.

The number of polyfunctional isocyanate compounds (B) may be one, or two or more.

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

Examples of aromatic polyisocyanates include 1,3-phenylene diisocyanate, 4,4'-diphenyldiisocyanate, 1,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6 - tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-toluidine diisocyanate, 2,4,6-triisocyanatotoluene, 1,3,5-triisocyanatobenzene, dianisidine diisocyanate, 4,4'- diphenyl ether diisocyanate, 4,4′,4″-triphenylmethane triisocyanate, 1,5-naphthalene diisocyanate, and xylylene diisocyanate.

Examples of aliphatic polyisocyanates include trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, dodecamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate may be mentioned.

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

Examples of alicyclic polyisocyanates include 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2 ,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, 4,4′-methylenebis(cyclohexyl isocyanate), 1,4-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, isophorone diisocyanate , hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated tetramethylxylylene diisocyanate.

Examples of the polyfunctional isocyanate compound (B) include trimethylolpropane adducts, water-reacted biuret forms, and trimers having an isocyanurate ring of various polyfunctional isocyanate compounds as described above. Moreover, these can be used together.

The content of the polyfunctional isocyanate compound (B) in the urethane-based pressure-sensitive adhesive composition is preferably 2.0 parts by weight to 40 parts by weight with respect to 100 parts by weight of the base polymer, in order to further express the effects of the present invention. parts by weight, more preferably 2.3 to 30 parts by weight, still more preferably 2.5 to 20 parts by weight, and particularly preferably 3.0 to 15 parts by weight.

The equivalent ratio of NCO groups and OH groups in the urethane-based pressure-sensitive adhesive composition is preferably 1.0 to 2.0 as NCO groups/OH groups, and more It is preferably 1.1 to 1.9, more preferably 1.2 to 1.8, and particularly preferably 1.2 to 1.7.

<<1-1-4. Fluorine compounds≫
A urethane pressure-sensitive adhesive composition contains a fluorine-based compound. When the urethane-based pressure-sensitive adhesive composition contains a fluorine-based compound, the effects of the present invention can be exhibited more.

Only one type of fluorine-based compound may be used, or two or more types may be used.

The content of the fluorine-based compound in the urethane pressure-sensitive adhesive composition is preferably 0.01 parts by weight or more, more preferably 0.01 parts by weight or more, relative to 100 parts by weight of the base polymer, in order to achieve the effects of the present invention. is 0.03 to 30 parts by weight, more preferably 0.05 to 10 parts by weight, particularly preferably 0.05 to 1 part by weight.

The fluorine-based compound preferably has a surface tension of 23 mN/m or more, more preferably 23 mN/m to 26 mN/m when it is made into a 0.1% propylene glycol monomethyl ether solution (the surface tension of propylene glycol monomethyl ether is tension is 27.1 mN/m). If the surface tension of the 0.1% propylene glycol monomethyl ether solution of the fluorine-based compound is within the above range, the effect of the present invention can be further exhibited. In particular, if the surface tension of the 0.1% propylene glycol monomethyl ether solution of the fluorine-based compound is within the above range, the occurrence of black spots can be more effectively suppressed.

Examples of the fluorine-based compound include at least one selected from fluorine-containing compounds, hydroxyl group-containing fluorine-based compounds, and crosslinkable functional group-containing fluorine-based compounds.

The fluorine-containing compound includes, for example, 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. Fluoroaliphatic hydrocarbon backbones include, for example, fluoroC1-C10 alkanes such as fluoromethane, fluoroethane, fluoropropane, fluoroisopropane, fluorobutane, fluoroisobutane, fluoro-t-butane, fluoropentane, and fluorohexane. . Here, the notation "C1-C10" means 1-10 carbon atoms.

A preferred embodiment of the fluorine-containing compound is an oligomer (“specific fluorine compound”) having a fluorine-containing group and a hydrophilic group and/or a lipophilic group.

Typical fluorine-containing groups include fluorine-containing alkyl groups (eg, CF ₃ —) and/or fluorine-containing alkylene groups (eg, —CF ₂ —CF ₂ —).

A hydrophilic group is a group having hydrophilicity, and hydrophilicity is translated into English as "hydrophilic" and is a property generally known to those skilled in the art as "having an affinity for water". (See, for example, McGraw-Hill Encyclopedia of Science and Technology Terms (revised 3rd edition, Nikkan Kogyo Shimbun, Ltd.), etc.). A lipophilic group is a group having lipophilic properties, and lipophilicity is translated in English as "lipophilic" and is a property generally known to those skilled in the art as "having an affinity for oils". (See, for example, McGraw-Hill Encyclopedia of Science and Technology Terms (revised 3rd edition, Nikkan Kogyo Shimbun, Ltd.), etc.).

By adopting such a "specific fluorine-based compound" as the fluorine-based compound, the effects of the present invention can be further exhibited. In particular, by adopting the "specific fluorine-based compound" as the fluorine-based compound, the surface protection film according to the embodiment of the present invention can exhibit excellent easy peelability.

When such a "specific fluorine-based compound" is used in combination with an ionic compound described later, the antistatic performance of the surface protection film according to the embodiment of the present invention can be further improved. This is presumably because the specific fluorine-based compound causes the ionic compound to be unevenly distributed on the surface side of the urethane-based pressure-sensitive adhesive layer (the side to be bonded to the adherend).

Commercially available fluorine-containing compounds include, for example, the following.

Megafuck series manufactured by DIC Corporation:
Typically, "Megafuck F-114", "Megafuck F-253", "Megafuck F-281", "Megafuck F-410", "Megafuck F-430", "Megafuck F- 444”, “Megafuck F-477”, “Megafuck F-510”, “Megafuck F-551”, “Megafuck F-553”, “Megafuck F-554”, “Megafuck F-556” , "Megafuck F-557", "Megafuck F-559", "Megafuck F-561", "Megafuck F-562", "Megafuck F-565", "Megafuck F-568", " Megafuck F-570", "Megafuck F-571", "Megafuck F-576", "Megafuck R-01", "Megafuck R-40", "Megafuck R-40-LM", " Megafuck R-41", "Megafuck R-41-LM", "Megafuck R-94", "Megafuck RS-56", "Megafuck RS-72-K", "Megafuck RS-75- A”, “Megafuck RS-75-NS”, etc.

Surflon series manufactured by AGC Seimi Chemical Co., Ltd.:
Typical examples are "S-242", "S-243", "S-386" and the like.

FC series manufactured by Sumitomo 3M:
Typical examples are "FC-4430" and "FC-4432".

Futergent series manufactured by Neos Co., Ltd.:
Representative examples are "Ftergent 100", "Ftergent 100C", "Ftergent 110", "Ftergent 150", "Ftergent 150CH", "Ftergent 250", "Ftergent 400SW" and the like.

PF series manufactured by Kitamura Chemical Industry Co., Ltd.:
Typically, "PF-136A", "PF-156A", "PF-151N", "PF-636", "PF-6320", "PF-656", "PF-6520", "PF- 651”, “PF-652”, “PF-3320”, etc.

As the hydroxyl group-containing fluorine-based compound, for example, conventionally known resins can be used. No. 97/11130 pamphlet, and International Publication No. 96/26254 pamphlet. Other hydroxyl group-containing fluororesins include, for example, JP-A-8-231919, JP-A-10-265731, JP-A-10-204374, JP-A-8-12922, and the like. polymers. In addition, a copolymer of a compound having a fluorinated alkyl group in a hydroxyl group-containing compound, a fluorine-containing organic compound obtained by copolymerizing a fluorine-containing compound in a hydroxyl group-containing compound, a fluorine-containing compound containing a hydroxyl group-containing organic compound, and the like. Examples of such hydroxyl group-containing fluorine-based compounds include commercially available products such as "Lumiflon" (manufactured by Asahi Glass Co., Ltd.), "Cefral Coat" (manufactured by Central Glass Co., Ltd.), and "Zaflon" (trade name). (manufactured by Toagosei Co., Ltd.) and trade name "Zeffle" (manufactured by Daikin Industries, Ltd.).

Examples of crosslinkable functional group-containing fluorine-based compounds include carboxylic acid compounds having a fluorinated alkyl group such as perfluorooctanoic acid, and compounds having a crosslinkable functional group-containing compound having a fluorinated alkyl group. Polymers, fluorine-containing organic compounds obtained by copolymerizing fluorine-containing compounds with crosslinkable functional group-containing compounds, and fluorine-containing compounds containing crosslinkable functional group-containing compounds can be mentioned. Such crosslinkable functional group-containing fluorine-based compounds include commercially available products such as "Megafac F-570", "Megafac RS-55", "Megafac RS-56", and "Megafac RS-72-K", "Megafac RS-75", "Megafac RS-76-E", "Megafac RS-76-NS", "Megafac RS-78", "Megafac RS-90" (manufactured by DIC Corporation).

Among commercially available fluorine-containing compounds, those corresponding to the above-mentioned "oligomer having a fluorine-containing group and a hydrophilic group and/or a lipophilic group" are typically available from DIC Corporation. made of
"Megafac F-251" (fluorine-containing group/hydrophilic group/lipophilic group-containing oligomer, surface tension = 22.7 mN/m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-477" (fluorine-containing group-hydrophilic group-lipophilic group-containing oligomer, surface tension = 25.4 mN / m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-551" (fluorinated group/lipophilic group-containing oligomer, surface tension = 25.9 mN/m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-553" (fluorine-containing group-hydrophilic group-lipophilic group-containing oligomer, surface tension = 25.4 mN / m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-554" (fluorinated group/lipophilic group-containing oligomer, surface tension = 25.0 mN/m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-555" (fluorine-containing group-hydrophilic group-lipophilic group-containing oligomer, surface tension = 20.5 mN / m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-557" (fluorine-containing group-hydrophilic group-lipophilic group-containing oligomer, surface tension = 25.6 mN / m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-559" (fluorine-containing group-hydrophilic group-lipophilic group-containing oligomer, surface tension = 24.3 mN / m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-563" (fluorinated group/lipophilic group-containing oligomer, surface tension = 21.4 mN/m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-569" (fluorinated group/hydrophilic group-containing oligomer, surface tension = 19.7 mN/m when used as a 0.1% propylene glycol monomethyl ether solution),
"Megafac F-571" (fluorinated group/hydrophilic group-containing oligomer, surface tension = 24.2 mN/m when used as a 0.1% propylene glycol monomethyl ether solution),
etc.

<<1-1-5. Ionic compounds≫
The urethane pressure-sensitive adhesive composition may contain an ionic compound. When the urethane pressure-sensitive adhesive composition contains an ionic compound, the antistatic performance of the surface protective film according to the embodiment of the present invention can be improved.

As the content of the ionic compound, any appropriate content can be adopted as long as the effects of the present invention are not impaired. In order to further improve the antistatic performance of the surface protective film of the present invention, the content of the ionic compound in the urethane pressure-sensitive adhesive composition is preferably 0.05 parts by weight with respect to 100 parts by weight of the base polymer. above, more preferably 0.10 parts by weight to 50 parts by weight, still more preferably 0.20 parts by weight to 30 parts by weight, particularly preferably 0.30 parts by weight to 10 parts by weight, and most preferably It is preferably 0.40 to 1 part by weight. If the content of the ionic compound in the urethane-based pressure-sensitive adhesive composition is too small outside the above range, the surface protective film of the present invention may not have sufficient antistatic performance. If the content of the ionic compound in the urethane-based pressure-sensitive adhesive composition is out of the above range and is too high, the adherend may be more contaminated.

As the ionic compound, any appropriate ionic compound can be adopted as long as the effects of the present invention are not impaired.

Only one kind of ionic compound may be used, or two or more kinds thereof may be used.

The ionic compound is preferably an ionic compound containing at least one selected from onium cations and metal cations and a fluoroorganic anion, and an ionic group-containing silicone oligomer, in that the effects of the present invention can be further exhibited. An ionic compound containing at least one selected from onium cations and metal cations and a fluoroorganic anion is more preferable in that the appearance of the pressure-sensitive adhesive layer can be improved.

The ionic compound may be an ionic liquid. An ionic liquid means a molten salt (ionic compound) that exhibits a liquid state at 25°C.

As the ionic group-containing silicone oligomer, any suitable ionic group-containing silicone oligomer can be employed as long as the effects of the present invention are not impaired. Examples of ionic group-containing silicone oligomers include the trade name "X-40-2450" manufactured by Shin-Etsu Chemical Co., Ltd.

As the onium cation, any appropriate onium cation can be adopted as long as the effects of the present invention are not impaired. From the viewpoint that the effects of the present invention can be more expressed, such onium cations are preferably ammonium cations (nitrogen-containing onium cations), sulfonium cations (sulfur-containing onium cations), and phosphorus-containing onium cations (phosphonium cations). At least one selected, more preferably an ammonium cation.

Any appropriate metal cation can be employed as the metal cation as long as the effects of the present invention are not impaired. Such metal cations are preferably alkali metal cations such as Li cations, Na cations, and K cations, in that the effects of the present invention can be expressed more effectively.

As the fluoroorganic anion, any suitable fluoroorganic anion can be employed as long as the effects of the present invention are not impaired. The fluoroorganic anions may be fully fluorinated (perfluorinated) or partially fluorinated.

Such fluoroorganic anions include, for example, fluorinated arylsulfonates, perfluoroalkanesulfonates, bis(fluorosulfonyl)imides, bis(perfluoroalkanesulfonyl)imides, cyanoperfluoroalkanesulfonylamides, bis(cyano) perfluoroalkanesulfonylmethide, cyano-bis-(perfluoroalkanesulfonyl)methide, tris(perfluoroalkanesulfonyl)methide, trifluoroacetate, perfluoroalkylate, tris(perfluoroalkanesulfonyl)methide, (perfluoroalkane sulfonyl)trifluoroacetamide and the like.

Among these fluoroorganic anions, perfluoroalkylsulfonates, bis(fluorosulfonyl)imides, and bis(perfluoroalkanesulfonyl)imides are preferred from the viewpoint that the effects of the present invention can be more expressed. More specifically, is for example trifluoromethanesulfonate, pentafluoroethanesulfonate, heptafluoropropanesulfonate, nonafluorobutanesulfonate, bis(fluorosulfonyl)imide, bis(trifluoromethanesulfonyl)imide, preferably bis(fluorosulfonyl)imide, Bis(trifluoromethanesulfonyl)imide.

As the ionic compound, an ionic compound composed of an onium cation and a fluoroorganic anion is more preferable in that the effects of the present invention can be exhibited more effectively.

The onium cation preferably has at least one selected from structures represented by general formulas (3) to (6).

In general formula (3), Ra represents a hydrocarbon group having 4 to 20 carbon atoms and may contain a heteroatom; It represents a hydrogen group and may contain a heteroatom. However, when the nitrogen atom contains a double bond, there is no Rc.

In general formula (4), Rd represents a hydrocarbon group having 2 to 20 carbon atoms and may contain a heteroatom, and Re, Rf, and Rg are the same or different and are hydrogen or It represents 16 hydrocarbon groups and may contain heteroatoms.

In general formula (5), Rh represents a hydrocarbon group having 2 to 20 carbon atoms and may contain a heteroatom; Ri, Rj, and Rk are the same or different and are hydrogen or It represents 16 hydrocarbon groups and may contain heteroatoms.

In general formula (6), Z represents a nitrogen atom, a sulfur atom, or a phosphorus atom; Rl, Rm, Rn, and Ro are the same or different and represent a hydrocarbon group having 1 to 20 carbon atoms; It may contain atoms. However, when Z is a sulfur atom, there is no Ro.

Examples of the cation structure represented by the general formula (3) include a pyridinium cation structure, a pyrrolidinium cation structure, a piperidinium cation structure, a cation structure having a pyrroline skeleton, and a cation structure having a pyrrole skeleton.

Specific examples of the cation represented by formula (3) include 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-ethyl-3-methylpyridinium cation, 1-butyl -3-methylpyridinium cation, 1-hexyl-3-methylpyridinium cation, 1-butyl-4-methylpyridinium cation, 1-octyl-4-methylpyridinium cation, 1-butyl-3,4-dimethylpyridinium cation, pyridinium cations such as 1,1-dimethylpyrrolidinium cation; 1-ethyl-1-methylpyrrolidinium cation, 1-methyl-1-propylpyrrolidinium cation, 1-methyl-1-butylpyrrolidinium cation, 1-methyl-1-pentylpyrrolidinium cation, 1-methyl-1-hexylpyrrolidinium cation, 1-methyl-1-heptylpyrrolidinium cation, 1-ethyl-1-propylpyrrolidinium cation, 1 -ethyl-1-butylpyrrolidinium cation, 1-ethyl-1-pentylpyrrolidinium cation, 1-ethyl-1-hexylpyrrolidinium cation, 1-ethyl-1-heptylpyrrolidinium cation, 1 , 1-dipropylpyrrolidinium cation, 1-propyl-1-butylpyrrolidinium cation, pyrrolidinium cations such as 1,1-dibutylpyrrolidinium cation; 1-propylpiperidinium cation, 1-pentylpi peridinium cation, 1-methyl-1-ethylpiperidinium cation, 1-methyl-1-propylpiperidinium cation, 1-methyl-1-butylpiperidinium cation, 1-methyl-1-pentylpiperidinium Cation, 1-methyl-1-hexylpiperidinium cation, 1-methyl-1-heptylpiperidinium cation, 1-ethyl-1-propylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation , 1-ethyl-1-pentylpiperidinium cation, 1-ethyl-1-hexylpiperidinium cation, 1-ethyl-1-heptylpiperidinium cation, 1-propyl-1-butylpiperidinium cation, Piperidinium cations such as 1,1-dimethylpiperidinium cation, 1,1-dipropylpiperidinium cation, 1,1-dibutylpiperidinium cation; 2-methyl-1-pyrroline cation; 1-ethyl- _{2 -} phenylindole cation; 1,2 _- dimethylindole cation; 1-ethylcarbazole cation; a cation having at least one selected;

Among these, 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-ethyl-3-methylpyridinium cation, 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-ethylpyridinium cation, 1 -pyridinium cations such as butyl-3-methylpyridinium cation, 1-hexyl-3-methylpyridinium cation, 1-butyl-4-methylpyridinium cation, 1-octyl-4-methylpyridinium cation; 1-ethyl-1- methylpyrrolidinium cation, 1-methyl-1-propylpyrrolidinium cation, 1-methyl-1-butylpyrrolidinium cation, 1-methyl-1-pentylpyrrolidinium cation, 1-methyl-1-hexyl pyrrolidinium cation, 1-methyl-1-heptylpyrrolidinium cation, 1-ethyl-1-propylpyrrolidinium cation, 1-ethyl-1-butylpyrrolidinium cation, 1-ethyl-1-pentylpyrrolidinium cation cation, 1-ethyl-1-hexylpyrrolidinium cation, 1-ethyl-1-heptylpyrrolidinium cation; 1-methyl-1-ethylpiperidinium cation, 1-methyl -1-propylpiperidinium cation, 1-methyl-1-butylpiperidinium cation, 1-methyl-1-pentylpiperidinium cation, 1-methyl-1-hexylpiperidinium cation, 1-methyl-1 -heptylpiperidinium cation, 1-ethyl-1-propylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, 1-ethyl-1-pentylpiperidinium cation, 1-ethyl-1- piperidinium cations such as hexylpiperidinium cation, 1-ethyl-1 _- heptylpiperidinium cation, 1-propyl-1-butylpiperidinium cation; group) and an allyl group (CH ₂ ═CH—CH ₂ — group); more preferably, 1-hexylpyridinium cation and 1-ethyl-3-methylpyridinium cation , 1-butyl-3-methylpyridinium cation, 1-octyl-4-methylpyridinium cation, 1-methyl-1-propylpyrrolidinium cation, 1-methyl-1-propylpiperidinium cation, these cations further A cation having at least one selected from a vinyl group (CH ₂ =CH- group) and an allyl group (CH ₂ =CH-CH ₂ - group).

Examples of the cation structure represented by general formula (4) include an imidazolium cation structure, a tetrahydropyrimidinium cation structure, and a dihydropyrimidinium cation structure.

Specific examples of the cation represented by the general formula (4) include 1,3-dimethylimidazolium cation, 1,3-diethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 1-butyl -3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, 1-octyl-3-methylimidazolium cation, 1-decyl-3-methylimidazolium cation, 1-dodecyl-3-methylimidazolium cation lithium cation, 1-tetradecyl-3-methylimidazolium cation, 1,2-dimethyl-3-propylimidazolium cation, 1-ethyl-2,3-dimethylimidazolium cation, 1-butyl-2,3-dimethylimidazolium cation imidazolium cations such as lithium cations, 1-hexyl-2,3-dimethylimidazolium cations; 1,3-dimethyl-1,4,5,6-tetrahydropyrimidinium cations, 1,2,3-trimethyl- 1,4,5,6-tetrahydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3,5-tetramethyl- Tetrahydropyrimidinium cations such as 1,4,5,6-tetrahydropyrimidinium cations; 1,3-dimethyl-1,4-dihydropyrimidinium cations, 1,3-dimethyl-1,6-dihydropyrimidinium cations cation, 1,2,3-trimethyl-1,4-dihydropyrimidinium cation, 1,2,3-trimethyl-1,6-dihydropyrimidinium cation, 1,2,3,4-tetramethyl- Dihydropyrimidinium cations such as 1,4-dihydropyrimidinium cation, 1,2,3,4 _- tetramethyl-1,6-dihydropyrimidinium cation; - group) and a cation having at least one selected from an allyl group (CH ₂ =CH-CH ₂ - group);

Among these, 1,3-dimethylimidazolium cation, 1,3-diethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 1 -butyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, 1-octyl-3-methylimidazolium cation, 1-decyl-3-methylimidazolium cation, 1-dodecyl-3- methylimidazolium cation, 1-tetradecyl-3-methylimidazolium cation, and at least one of these cations further selected from a vinyl group (CH ₂ =CH- group) and an allyl group (CH ₂ =CH-CH _2- group) imidazolium cations such as cations having a seed, more preferably 1-ethyl-3-methylimidazolium cation, 1-hexyl-3-methylimidazolium cation, these cations further having a vinyl group (CH ₂ = CH— group) and an allyl group (CH ₂ ═CH—CH ₂ — group).

Examples of the cation structure represented by general formula (5) include a pyrazolium cation structure and a pyrazolinium cation structure.

Specific examples of the cation represented by the general formula (5) include, for example, 1-methylpyrazolium cation, 3-methylpyrazolium cation, 1-ethyl-2-methylpyrazolinium cation, 1-ethyl- pyrazolium cations such as 2,3,5-trimethylpyrazolium cation, 1-propyl-2,3,5-trimethylpyrazolium cation, 1-butyl-2,3,5-trimethylpyrazolium cation; pyrazolinium cation such as 1-ethyl-2,3,5-trimethylpyrazolinium cation, 1-propyl-2,3,5-trimethylpyrazolinium cation, 1-butyl-2,3,5-trimethylpyrazolinium cation Zolinium cations; cations further having at least one selected from a vinyl group (CH ₂ =CH- group) and an allyl group (CH ₂ =CH-CH ₂ - group);

Examples of the cation structure represented by the general formula (6) include, for example, a tetraalkylammonium cation structure, a trialkylsulfonium cation structure, a tetraalkylphosphonium cation structure, and a part of the above alkyl group being an alkenyl group, an alkoxyl group, or an epoxy group. Those substituted with are mentioned.

Specific examples of the cation represented by formula (6) include tetramethylammonium cation, tetraethylammonium cation, tetrabutylammonium cation, tetrapentylammonium cation, tetrahexylammonium cation, tetraheptylammonium cation, and triethylmethylammonium. cations, tributylethylammonium cation, trimethylpropylammonium cation, trimethyldecylammonium cation, N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium cation, glycidyltrimethylammonium cation, diallyldimethylammonium cation, N, N-dimethyl-N-ethyl-N-propylammonium cation, N,N-dimethyl-N-ethyl-N-butylammonium cation, N,N-dimethyl-N-ethyl-N-pentylammonium cation, N,N- Dimethyl-N-ethyl-N-hexylammonium cation, N,N-dimethyl-N-ethyl-N-heptylammonium cation, N,N-dimethyl-N-ethyl-N-nonylammonium cation, N,N-dimethyl- N,N-dipropylammonium cation, N,N-diethyl-N-propyl-N-butylammonium cation, N,N-dimethyl-N-propyl-N-pentylammonium cation, N,N-dimethyl-N-propyl -N-hexylammonium cation, N,N-dimethyl-N-propyl-N-heptylammonium cation, N,N-dimethyl-N-butyl-N-hexylammonium cation, N,N-diethyl-N-butyl-N -heptylammonium cation, N,N-dimethyl-N-pentyl-N-hexylammonium cation, N,N-dimethyl-N,N-dihexylammonium cation, trimethylheptylammonium cation, N,N-diethyl-N-methyl- N-propylammonium cation, N,N-diethyl-N-methyl-N-pentylammonium cation, N,N-diethyl-N-methyl-N-heptylammonium cation, N,N-diethyl-N-propyl-N- Pentylammonium cation, triethylpropylammonium cation, triethylpentylammonium cation, triethylheptylammonium cation, N,N-dipropyl-N-methyl-N-ethylammonium cation, N,N-dipropyl-N-methyl-N-pentylammonium cation , N,N-dipropyl-N-butyl-N-hexylammonium cation, N,N-dipropyl-N,N-dihexylammonium cation, N,N-dibutyl-N-methyl-N-pentylammonium cation, N,N -tetraalkylammonium cations such as dibutyl-N-methyl-N-hexylammonium cation, trioctylmethylammonium cation, N-methyl-N-ethyl-N-propyl-N-pentylammonium cation; trimethylsulfonium cation, triethylsulfonium cation , tributylsulfonium cation, trihexylsulfonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, trialkylsulfonium cation such as dimethyldecylsulfonium cation; tetramethylphosphonium cation, tetraethylphosphonium cation, tetrabutylphosphonium cation, tetrahexylphosphonium cation, tetraalkylphosphonium cations such as tetraoctylphosphonium _cation , triethylmethylphosphonium cation, tributylethylphosphonium cation _, trimethyldecylphosphonium cation; a cation having at least one selected from (CH ₂ -group);

The ionic compound is preferably an ionic compound containing at least one selected from the above onium cations and the above metal cations and the above fluoroorganic anion, or an ionic group-containing silicone oligomer, more preferably the above and at least one selected from the above metal cations and the above fluoroorganic anion, and more preferably an ionic compound containing the above onium cation and the above fluoroorganic anion.

The ionic compound is preferably 1-hexylpyridinium bis(fluorosulfonyl)imide, 1-ethyl-3-methylpyridinium trifluoromethanesulfonate, 1 - ethyl-3-methylpyridinium pentafluoroethanesulfonate, 1-ethyl-3-methylpyridinium heptafluoropropanesulfonate, 1-ethyl-3-methylpyridinium nonafluorobutanesulfonate, 1-butyl-3-methylpyridinium trifluoromethanesulfonate, 1-butyl-3-methylpyridinium bis(trifluoromethanesulfonyl)imide, 1-octyl-4-methylpyridinium bis(fluorosulfonyl)imide, 1-methyl-1-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1 -methyl-1-propylpyrrolidinium bis(fluorosulfonyl)imide, 1-methyl-1-propylpiperidinium bis(trifluoromethanesulfonyl)imide, 1-methyl-1-propylpiperidinium bis(fluorosulfonyl)imide , 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, 1-ethyl-3-methylimidazolium heptafluoropropanesulfonate, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-ethyl-3 -methylimidazolium bis(fluorosulfonyl)imide, 1-hexyl-3-methylimidazolium bis(fluorosulfonyl)imide, 1-allyl-3-methyl-imidazolium trifluoromethanesulfonate, 1-allyl-3-methyl-imidazo Lithium heptafluoropropanesulfonate, 1-allyl-3-methyl-imidazolium bis(trifluoromethanesulfonyl)imide, 1-allyl-3-methyl-imidazolium bis(fluorosulfonyl)imide, methyltrioctylammonium bis(trifluoromethanesulfonyl) ) imide, trimethylpropylammonium bis(trifluoromethanesulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, more preferably 1-butyl-3-methylpyridinium bis(trifluoromethanesulfonyl ) imide, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide, 1-allyl-3-methyl-imidazolium bis(trifluoromethanesulfonyl)imide, methyltrioctylammonium bis(trifluoromethanesulfonyl)imide, trimethyl propylammonium bis(trifluoromethanesulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, particularly preferably 1-butyl-3-methylpyridinium bis(trifluoromethanesulfonyl)imide, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide, 1-allyl-3-methyl-imidazolium bis(trifluoromethanesulfonyl)imide, methyltrioctylammonium bis(trifluoromethanesulfonyl)imide, trimethylpropylammonium bis(trifluoromethanesulfonyl)imide.

Commercially available ionic compounds may be used, or those synthesized by any appropriate method may be used. For example, ionic liquids can be prepared by the halide method, hydroxide method, acid ester method, complex formation method, as described in "Ionic liquids - the front line of development and the future" (published by CMC Publishing). and may be synthesized by a neutralization method or the like.

<<1-1-6. Other Ingredients≫
The urethane-based pressure-sensitive adhesive composition may contain any appropriate other component within a range that does not impair the effects of the present invention. Examples of such other components include resin components other than the base polymer, cross-linking agents other than the polyfunctional isocyanate compound (B), cross-linking retarders, silicone additives, fatty acid esters, tackifiers, inorganic fillers, Organic fillers, metal powders, pigments, foils, softeners, antioxidants, conductive agents, UV absorbers, antioxidants, light stabilizers, surface lubricants, leveling agents, corrosion inhibitors, heat stabilizers, Polymerization inhibitors, lubricants, catalysts and solvents can be mentioned. Other representative ingredients are described below.

[Silicone additive]
It is one of preferred embodiments that the urethane pressure-sensitive adhesive composition contains a silicone additive. When a silicone-based additive is included as another component, it becomes possible to further improve the easy releasability of the surface protective film according to the embodiment of the present invention.

From the point of view that the effects of the present invention can be more expressed, the content of the silicone additive in the urethane pressure-sensitive adhesive composition is preferably 0.01 parts by weight or more with respect to 100 parts by weight of the base polymer. It is preferably 0.03 to 30 parts by weight, more preferably 0.05 to 10 parts by weight, and particularly preferably 0.05 to 1 part by weight.

As the silicone additive, any appropriate silicone additive can be employed as long as the effects of the present invention are not impaired.

Only one type of silicone additive may be used, or two or more types may be used.

From the point of view that the effect of the present invention can be more expressed, the total content of the silicone additive and the fluorine additive is preferably 0.01 part by weight or more with respect to 100 parts by weight of the base polymer. , more preferably 0.03 to 30 parts by weight, still more preferably 0.05 to 10 parts by weight, and particularly preferably 0.05 to 1 part by weight.

Any appropriate silicone-based additive can be adopted as the silicone-based additive as long as it does not impair the effects of the present invention. Examples of such silicone additives include reactive silicone oils and non-reactive silicone oils.

Reactive silicone oils include, for example, side chain type reactive silicone oils in which organic groups are bonded as side chains to Si atoms that provide siloxane bonds, and double-end type in which organic groups are bonded to Si atoms located at both ends of the structure. Reactive silicone oil, single-end reactive silicone oil in which an organic group is bonded only to one of the Si atoms located at both ends of the structure, organic groups are bonded as side chains to the Si atoms used for siloxane bonding, and both ends of the structure Side chain double-ended reactive silicone oils in which an organic group is bonded to the Si atom located at the end are exemplified.

〔Antioxidant〕
The urethane-based pressure-sensitive adhesive composition may contain an antioxidant as another component from the viewpoint of suppressing deterioration of the urethane-based pressure-sensitive adhesive layer. Only one kind of antioxidant may be used, or two or more kinds thereof may be used.

Any appropriate content can be adopted as the content of the antioxidant in the urethane-based pressure-sensitive adhesive composition as long as the effects of the present invention are not impaired. The content of the antioxidant in the urethane pressure-sensitive adhesive composition is preferably 0.01 to 10 parts by weight, more preferably 0.05 to 5 parts by weight, relative to 100 parts by weight of the base polymer. parts, more preferably 0.1 to 3 parts by weight, and particularly preferably 0.2 to 1 part by weight.

Antioxidants include, for example, radical chain inhibitors and peroxide decomposers.

Examples of radical chain inhibitors include phenol antioxidants and amine antioxidants.

Examples of peroxide decomposers include sulfur-based antioxidants and phosphorus-based antioxidants.

Examples of phenolic antioxidants include monophenolic antioxidants, bisphenolic antioxidants, and polymeric phenolic antioxidants.

Examples of monophenol antioxidants include 2,6-di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearin-β-( 3,5-di-t-butyl-4-hydroxyphenyl)propionate.

Examples of bisphenol antioxidants include 2,2'-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 4,4' -thiobis(3-methyl-6-t-butylphenol), 4,4′-butylidenebis(3-methyl-6-t-butylphenol), 3,9-bis[1,1-dimethyl-2-[β-( 3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl]2,4,8,10-tetraoxaspiro[5,5]undecane.

Examples of polymeric phenolic antioxidants include 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, 1,3,5-trimethyl-2,4, 6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, tetrakis-[methylene-3-(3′,5′-di-t-butyl-4′-hydroxyphenyl)propionate]methane , bis[3,3′-bis-(4′-hydroxy-3′-t-butylphenyl)butyric acid]glycol ester, 1,3,5-tris(3′,5′-di-t-butyl -4′-hydroxybenzyl)-S-triazine-2,4,6-(1H,3H,5H)trione, tocopherol.

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

Phosphorus-based antioxidants include, for example, triphenylphosphite, diphenylisodecylphosphite, and phenyldiisodecylphosphite.

[Ultraviolet absorber]
The urethane-based pressure-sensitive adhesive composition may contain an ultraviolet absorber as another component from the viewpoint of suppressing deterioration of the urethane-based pressure-sensitive adhesive layer. Only one ultraviolet absorber may be used, or two or more ultraviolet absorbers may be used.

Any appropriate content can be adopted as the content of the ultraviolet absorber in the urethane-based pressure-sensitive adhesive composition as long as the effects of the present invention are not impaired. The content of the ultraviolet absorber in the urethane pressure-sensitive adhesive composition is preferably 0.01 parts by weight to 10 parts by weight or more, more preferably 0.05 parts by weight to 5 parts by weight, relative to 100 parts by weight of the base polymer. Part by weight, more preferably 0.1 to 3 parts by weight, particularly preferably 0.2 to 1 part by weight.

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

Benzophenone-based UV absorbers include, for example, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2' -dihydroxy-4-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis(2-methoxy-4-hydroxy-5-benzoylphenyl ) methane.

Benzotriazole-based UV absorbers include, for example, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-5'-tert-butylphenyl)benzotriazole, 2-( 2′-hydroxy-3′,5′-di-tert-butylphenyl)benzotriazole, 2-(2′-hydroxy-3′-tert-butyl-5′-methylphenyl)-5-chlorobenzotriazole, 2 -(2'-hydroxy-3',5'-di-tert-butylphenyl)5-chlorobenzotriazole, 2-(2'-hydroxy-3',5'-di-tert-amylphenyl)benzotriazole, 2-(2'-hydroxy-4'-octoxyphenyl)benzotriazole, 2-[2'-hydroxy-3'-(3'',4'',5'',6'',-tetrahydrophthalimidomethyl )-5′-methylphenyl]benzotriazole, 2,2′methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], [2 (2'-Hydroxy-5'-methacryloxyphenyl)-2H-benzotriazole.

Examples of salicylic acid-based ultraviolet absorbers include phenyl salicylate, p-tert-butylphenyl salicylate, and p-octylphenyl salicylate.

Examples of cyanoacrylate ultraviolet absorbers include 2-ethylhexyl-2-cyano-3,3'-diphenyl acrylate and ethyl-2-cyano-3,3'-diphenyl acrylate.

[Light stabilizer]
The urethane-based pressure-sensitive adhesive composition may contain a light stabilizer as another component from the viewpoint of suppressing deterioration of the urethane-based pressure-sensitive adhesive layer. Only one kind of light stabilizer may be used, or two or more kinds thereof may be used.

Any appropriate content can be adopted as the content of the light stabilizer in the urethane-based pressure-sensitive adhesive composition as long as the effects of the present invention are not impaired. The content of the light stabilizer in the urethane pressure-sensitive adhesive composition is preferably 0.01 parts by weight to 10 parts by weight or more, more preferably 0.05 parts by weight to 5 parts by weight, relative to 100 parts by weight of the base polymer. Part by weight, more preferably 0.1 to 3 parts by weight, particularly preferably 0.2 to 1 part by weight.

Light stabilizers include, for example, hindered amine light stabilizers and ultraviolet stabilizers.

Examples of hindered amine light stabilizers include [bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate] and bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate. , methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate.

UV stabilizers include, for example, nickel bis(octylphenyl) sulfide, [2,2′-thiobis(4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-tert- Butyl-4-hydroxybenzyl-phosphate monoethylate, nickel-dibutyldithiocarbamate, benzoate-type quenchers, nickel-dibutyldithiocarbamate.

[Fatty acid ester]
From the viewpoint of improving the wettability of the urethane-based pressure-sensitive adhesive layer, the urethane-based pressure-sensitive adhesive composition may contain a fatty acid ester as another component. Only one kind of fatty acid ester may be used, or two or more kinds thereof may be used.

Any appropriate content ratio can be adopted as the content ratio of the fatty acid ester in the urethane-based pressure-sensitive adhesive composition as long as the effects of the present invention are not impaired. The content of the fatty acid ester in the urethane pressure-sensitive adhesive composition is preferably 0.01 to 50 parts by weight, more preferably 0.05 to 45 parts by weight, relative to 100 parts by weight of the base polymer. , more preferably 0.1 to 40 parts by weight, particularly preferably 0.5 to 25 parts by weight.

The number average molecular weight Mn of the fatty acid ester is preferably 200 to 400, more preferably 210 to 395, still more preferably 230 to 380, particularly preferably 240 to 360, most preferably 250 to 350. is. By adjusting the number average molecular weight Mn of the fatty acid ester within the above range, the wetting speed can be further improved. If the number average molecular weight Mn of the fatty acid ester is too small, the wetting speed may not improve even if the number of parts added is large. If the number average molecular weight Mn of the fatty acid ester is too large, the curability of the pressure-sensitive adhesive during drying may deteriorate, which may adversely affect not only wettability but also other pressure-sensitive adhesive properties.

As the fatty acid ester, any suitable fatty acid ester can be adopted as long as it does not impair the effects of the present invention. Examples of such fatty acid esters include polyoxyethylene bisphenol A laurate, butyl stearate, 2-ethylhexyl palmitate, 2-ethylhexyl stearate, monoglyceride behenate, cetyl 2-ethylhexanoate, and myristic acid. Isopropyl, isopropyl palmitate, cholesteryl isostearate, lauryl methacrylate, methyl cocoate, methyl laurate, methyl oleate, methyl stearate, myristyl myristate, octyldodecyl myristate, pentaerythritol monooleate, pentaerythritol monostearate , pentaerythritol tetrapalmitate, stearyl stearate, isotridecyl stearate, 2-ethylhexanoic acid triglyceride, butyl laurate, and octyl oleate.

〔catalyst〕
Any appropriate catalyst can be used as the catalyst that can be contained in the urethane pressure-sensitive adhesive composition, as long as the effects of the present invention are not impaired. Examples of such catalysts include tertiary amine compounds and organometallic compounds. Only one kind of catalyst may be used, or two or more kinds thereof may be used.

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

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

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

Examples of non-tin compounds include titanium compounds such as dibutyl titanium dichloride, tetrabutyl titanate, and butoxy titanium trichloride; lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate. iron-based compounds such as iron 2-ethylhexanoate and iron acetylacetonate; cobalt-based compounds such as cobalt benzoate and cobalt 2-ethylhexanoate; zinc-based compounds such as zinc naphthenate and zinc 2-ethylhexanoate; zirconium-based compounds such as zirconium naphthenate;

From the viewpoint that the effect of the present invention can be more expressed, the catalyst that can be contained in the urethane-based pressure-sensitive adhesive composition is preferably a non-tin compound, more preferably iron 2-ethylhexanoate, iron acetylacetonate, or the like. is an iron-based compound.

The amount of the catalyst that can be contained in the urethane pressure-sensitive adhesive composition is preferably 0.001% by weight to 1.0% by weight with respect to the total amount of the base polymer.

〔solvent〕
As the solvent that can be contained in the urethane pressure-sensitive adhesive composition, any suitable solvent can be used as long as the effects of the present invention are not impaired. Such solvents include, for example, methyl ethyl ketone, ethyl acetate, toluene, xylene, and acetone. Among these solvents, ethyl acetate and toluene are preferred.

<<<1-2. Base layer≫≫
Any appropriate thickness can be adopted as the thickness of the base material layer depending on the application. The thickness of the substrate layer is preferably 5 μm to 300 μm, more preferably 10 μm to 250 μm, even more preferably 15 μm to 200 μm, particularly preferably 20 μm to 150 μm.

The substrate layer may be a single layer or a laminate of two or more layers. The substrate layer may be stretched.

Any appropriate material can be adopted as the material of the base material layer depending on the application. Examples include plastics, paper, metal films, and non-woven fabrics. Preferably, it is plastic. The base material layer may be composed of one kind of material, or may be composed of two or more kinds of materials. For example, it may be composed of two or more types of plastics.

Examples of the plastic include polyester-based resins, polyamide-based resins, and polyolefin-based resins. Polyester-based resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate are preferred.

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

≪≪≪2. Method for producing surface protective film>>>>>>
Surface protection films according to embodiments of the present invention can be produced by any suitable method. As such a manufacturing method, for example,
(1) A method of applying a solution or hot melt of a material for forming an adhesive layer onto a substrate layer,
(2) a method according to which the pressure-sensitive adhesive layer coated and formed on the release liner is transferred onto the substrate layer;
(3) A method of extruding and coating the material for forming the pressure-sensitive adhesive layer onto the substrate layer,
(4) A method of extruding a substrate layer and an adhesive layer in two layers or multiple layers,
(5) A method of laminating a single adhesive layer on a substrate layer or a method of laminating two adhesive layers together with a laminate layer,
(6) A method of two-layer or multi-layer lamination of an adhesive layer and a substrate layer forming material such as a film or a laminate layer,
It can be performed according to any appropriate manufacturing method such as.

Examples of coating methods include roll coating, gravure roll coating, reverse roll coating, kiss roll coating, dip roll coating, bar coating, roll brushing, spray coating, knife coating, and air knife. A coating method, a comma coating method, a direct coating method, a die coating method, and a roll brush coating method can be used.

<<<<<3. Applications of Surface Protection Films>>>>>>
Surface protection films according to embodiments of the present invention may be used in any suitable application. Preferably, the surface protection film of the present invention causes very little contamination to adherends, and preferably has excellent wettability and reworkability, and is therefore preferably used for surface protection of optical members and electronic members, for example. Examples of optical members include LCDs, touch panels using LCDs, color filters used in LCDs, and polarizing plates.

A member to which the surface protective film according to the embodiment of the present invention is attached, such as an optical member or an electronic member, can be repeatedly attached and peeled manually with the attached surface protective film. .

That is, the optical member according to the embodiment of the present invention has the surface protective film of the present invention adhered thereto. Further, an electronic member according to an embodiment of the present invention has the surface protection film of the present invention adhered thereto.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited to these Examples. The tests and evaluation methods used in Examples and the like are as follows. "Parts" means "parts by weight" unless otherwise specified, and "%" means "% by weight" unless otherwise specified.

<Adhesive strength to glass>
A surface protection film (width 25 mm×length 140 mm) from which the release liner was removed was adhered to glass (soda lime glass, manufactured by Matsunami Glass Industry Co., Ltd.) using a 2-kg hand roller one reciprocation. After that, it was left for 30 minutes under an environmental temperature of 23°C. The obtained evaluation sample was measured with a tensile tester. As the tensile tester, a trade name "Autograph AG-Xplus HS 6000 mm/min high speed model (AG-50NX plus)" manufactured by Shimadzu Corporation was used. After setting the evaluation sample in the tensile tester, the tensile test was started. The conditions of the tensile test were a peeling angle of 180 degrees and a peeling speed (pulling speed) of 300 mm/min. The load when the surface protective film was peeled off from the glass was measured, and the average load at that time was defined as the adhesive strength (peeling force) of the surface protective film to glass.

<Peeling electrified voltage against glass>
The surface protective film from which the release liner was removed was cut into a size of 70 mm in width and 100 mm in length, and one end of the surface protective film was attached to the surface of glass (soda lime glass, manufactured by Matsunami Glass Industry Co., Ltd.). It was pressure-bonded with a hand roller so as to protrude from the end of the body by 30 mm. After leaving this sample in an environment of 23° C. and 50% RH for one day, it was set at a predetermined position on a 20 mm high sample fixing table. The end of the surface protective film protruding 30 mm from the adherend was fixed to an automatic winder (not shown), and the film was peeled off at a peeling angle of 150° and a peeling speed of 30 m/min. The potential on the surface of the adherend generated at this time was measured by a potential measuring device (manufactured by Shishido Electrostatic Co., Ltd., model "STATIRON DZ-4") fixed at a height of 30 mm from the center of the adherend. Peeling electrification voltage" was measured. The measurement was performed under the environment of 23° C. and 50% RH.

<Haze>
A urethane-based pressure-sensitive adhesive composition was applied to the release-treated surface of a 75 μm-thick polyester film (trade name: Diafoil MRF75, manufactured by Mitsubishi Chemical Corporation) whose one side was release-treated with silicone, under the conditions of Examples and Comparative Examples. After drying, a urethane pressure-sensitive adhesive layer was produced. Next, on the surface of the urethane-based adhesive layer, a 75 μm-thick polyester film (trade name: Diafoil MRE75, manufactured by Mitsubishi Chemical Corporation) with one side treated with silicone for release is applied, and the release-treated surface of the polyester film is a urethane-based adhesive. It was coated with the agent layer side, and aged at room temperature for 5 days.
Two pieces of 50 mm×50 mm cardboard with a hole of 20 mm×20 mm in the center were prepared, and the sample alone was adhered to one side by one reciprocation of a hand roller, and then the other side was adhered.
The haze of the evaluation sample obtained as described above was measured with "HM-150N" manufactured by Murakami Color Research Laboratory.

<Adhesive scum evaluation>
The surface protective film (width 25 mm×length 140 mm) from which the release liner had been removed was cut by inserting a cutter blade at 30 degrees into the center of the paste surface side to cut 1 cm.
A case where glue residue could be visually confirmed was rated as x, and a case where glue residue was not confirmed was rated as ◯.

<Black spot evaluation>
The amount of black spots (paste dents) generated per 10 cm square of the surface protective film from which the release liner was removed was visually confirmed.

<Percentage of hydroxyl groups contained in the urethane pressure-sensitive adhesive composition>
Based on the total 100 g hydroxyl value (OHV) of the base polymer contained in the urethane pressure-sensitive adhesive composition and the molecular weight (56.1) of KOH, it was calculated from the following formula.
OHV [mgKOH/g]/56.1 [mg/mmol] = OH [mmol/g]

[Production Example 1]: Production of Urethane Prepolymer A Solution Equipped with a 1 L round bottom separable flask, a separable cover, a separating funnel, a thermometer, a nitrogen inlet tube, a Liebig condenser, a vacuum seal, a stirring rod, and a stirring blade. 333 g of polytetramethylene glycol (product name "PTMG3000", manufactured by Mitsubishi Chemical Corporation) and 83 g of polypropylene glycol (product name "Sannix GP-1500", manufactured by Sanyo Kasei Co., Ltd.) were added to the experimental apparatus for polymerization. 110 g of ethyl acetate (manufactured by Tosoh Corporation) was added, and while stirring, 0.041 g of dibutyltin dilaurate (IV) (manufactured by Wako Pure Chemical Industries, Ltd.) was added as a catalyst, and nitrogen substitution was performed at room temperature for 1 hour. After that, 13.0 g of hexamethylene diisocyanate (product name “HDI”, manufactured by Tosoh Corporation) was added while stirring under nitrogen flow, and the temperature of the solution in the experimental apparatus was controlled to 90±2° C. with a water bath. The mixture was held for 4 hours while holding the temperature, and a solution of urethane prepolymer A was obtained. During the polymerization, ethyl acetate was added dropwise as appropriate in order to control the temperature during the polymerization and to prevent deterioration of the stirrability due to an increase in viscosity. The total amount of ethyl acetate added dropwise was 320 g. The solid content concentration of the solution of urethane prepolymer A was 50% by weight.

[Production Example 2]: Production of Urethane Prepolymer B Solution Equipped with a 1 L round bottom separable flask, a separable cover, a separating funnel, a thermometer, a nitrogen inlet tube, a Liebig condenser, a vacuum seal, a stirring rod, and a stirring blade. 197 g of polypropylene glycol (product name "Sannics PP-2000", manufactured by Sanyo Chemical Industries, Ltd.), 197 g of polyester polyol (product name "Kuraray Polyol P-2010", manufactured by Kuraray Co., Ltd.), 110 g of toluene (manufactured by Tosoh Corporation) as a solvent and 0.041 g of dibutyltin dilaurate (IV) (manufactured by Wako Pure Chemical Industries, Ltd.) as a catalyst were added, and nitrogen substitution was performed at room temperature for 1 hour while stirring. After that, 33.5 g of hexamethylene diisocyanate (product name “HDI”, manufactured by Tosoh Corporation) was added while stirring under nitrogen flow, and the temperature of the solution in the experimental apparatus was controlled to 90±2° C. with a water bath. After holding for 4 hours, 44 g of polypropylene glycol (product name "GP1000", manufactured by Sanyo Chemical Industries, Ltd.) was added, and the solution temperature in the experimental apparatus was controlled by a water bath to 90 ± 2 ° C. , After holding for 2 hours, 25.4 g of hexamethylene diisocyanate (product name "HDI", manufactured by Tosoh Corporation) was added, and the solution temperature in the experimental apparatus was controlled by a water bath to 90 ± 2 ° C. After holding for 2 hours, a solution of urethane prepolymer B was obtained. During the polymerization, toluene was added dropwise as appropriate in order to control the temperature during the polymerization and to prevent deterioration of the stirrability due to an increase in viscosity. The total amount of toluene dropped was 380 g. The solid content concentration of the solution of urethane prepolymer B was 50% by weight.

[Example 1]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (1). It was aged at room temperature for 5 days and evaluated.

[Example 2]
100 parts by weight of urethane prepolymer B, 2.9 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protection film (2). It was aged at room temperature for 5 days and evaluated.

[Example 3]
95 parts by weight of urethane prepolymer B, 3 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, PTGL3000 (Hodogaya Chemical Industry Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 2 parts by weight, 3.7 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (3). It was aged at room temperature for 5 days and evaluated.

[Example 4]
95 parts by weight of urethane prepolymer A, 3.5 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo), which is a polyol having three hydroxyl groups Kasei Co., Ltd., Mn = 3000) 1.5 parts by weight, isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) 3.8 parts by weight as a cross-linking agent, fluorinated oligomer Megafac F-571 (DIC Corporation) product) 0.5 parts by weight, as an antioxidant, Irganox 1010 (manufactured by BASF) 0.5 parts by weight, as a catalyst, Nasem ferric iron (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight, the total solid content The solution was diluted with ethyl acetate to 50% by weight to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (4). It was aged at room temperature for 5 days and evaluated.

[Example 5]
95 parts by weight of urethane prepolymer A, 3 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 2 parts by weight, 3.9 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protection film (5). It was aged at room temperature for 5 days and evaluated.

[Example 6]
80 parts by weight of urethane prepolymer A, 12 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 8 parts by weight, 6.0 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (6). It was aged at room temperature for 5 days and evaluated.

[Example 7]
60 parts by weight of urethane prepolymer A, 28 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 12 parts by weight, 8.0 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (7). It was aged at room temperature for 5 days and evaluated.

[Example 8]
60 parts by weight of urethane prepolymer A, 25 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups 15 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 8.6 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.), a fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation), 0.5 parts by weight. 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (8). It was aged at room temperature for 5 days and evaluated.

[Example 9]
50 parts by weight of urethane prepolymer A, 30 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP4000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=4000) 20 parts by weight, 8.7 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protection film (9). It was aged at room temperature for 5 days and evaluated.

[Example 10]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (10). It was aged at room temperature for 5 days and evaluated.

[Example 11]
100 parts by weight of urethane prepolymer B, 2.9 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (11). It was aged at room temperature for 5 days and evaluated.

[Example 12]
95 parts by weight of urethane prepolymer B, 3 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, PTGL3000 (Hodogaya Chemical Industry Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 2 parts by weight, 3.7 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (12). It was aged at room temperature for 5 days and evaluated.

[Example 13]
95 parts by weight of urethane prepolymer A, 3.5 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo), which is a polyol having three hydroxyl groups Kasei Co., Ltd., Mn = 3000) 1.5 parts by weight, 3.8 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, Fluorinated oligomer Megafac F-563 (DIC Corporation) product) 0.5 parts by weight, Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric iron (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, and the total solid content is The solution was diluted with ethyl acetate to 50% by weight to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (13). It was aged at room temperature for 5 days and evaluated.

[Example 14]
95 parts by weight of urethane prepolymer A, 3 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 2 parts by weight, 3.9 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (14). It was aged at room temperature for 5 days and evaluated.

[Example 15]
80 parts by weight of urethane prepolymer A, 12 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 8 parts by weight, 6.0 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (15). It was aged at room temperature for 5 days and evaluated.

[Example 16]
60 parts by weight of urethane prepolymer A, 28 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 12 parts by weight, 8.0 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (16). It was aged at room temperature for 5 days and evaluated.

[Example 17]
60 parts by weight of urethane prepolymer A, 25 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups 15 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 8.6 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.), a fluorine-based oligomer Megafac F-563 (manufactured by DIC Corporation), 0.5 parts by weight. 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The faces were laminated to obtain a surface protective film (17). It was aged at room temperature for 5 days and evaluated.

[Example 18]
50 parts by weight of urethane prepolymer A, 30 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP4000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=4000) 20 parts by weight, 8.7 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (18). It was aged at room temperature for 5 days and evaluated.

[Example 19]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-477 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (19). It was aged at room temperature for 5 days and evaluated.

[Example 20]
100 parts by weight of urethane prepolymer B, 2.9 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-477 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (20). It was aged at room temperature for 5 days and evaluated.

[Example 21]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-556 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The faces were laminated to obtain a surface protective film (21). It was aged at room temperature for 5 days and evaluated.

[Example 22]
100 parts by weight of urethane prepolymer B, 2.9 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-556 (manufactured by DIC) , Irganox 1010 (manufactured by BASF) 0.5 parts by weight as an antioxidant, Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, so that the total solid content is 50% by weight Diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (22). It was aged at room temperature for 5 days and evaluated.

[Example 23]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC) , 0.05 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and Irganox 1010 (manufactured by BASF) as an antioxidant. 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (23). It was aged at room temperature for 5 days and evaluated.

[Example 24]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC) , 0.10 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and Irganox 1010 (manufactured by BASF) as an antioxidant. 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (24). It was aged at room temperature for 5 days and evaluated.

[Example 25]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC) , 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and Irganox 1010 (manufactured by BASF) as an antioxidant. 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (25). It was aged at room temperature for 5 days and evaluated.

[Example 26]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC) 1.00 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 (manufactured by BASF) as an antioxidant, 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (26). It was aged at room temperature for 5 days and evaluated.

[Example 27]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-563 (manufactured by DIC) , 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and Irganox 1010 (manufactured by BASF) as an antioxidant. 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (27). It was aged at room temperature for 5 days and evaluated.

[Example 28]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-477 (manufactured by DIC) , 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and Irganox 1010 (manufactured by BASF) as an antioxidant. 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (28). It was aged at room temperature for 5 days and evaluated.

[Example 29]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-556 (manufactured by DIC) , 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, and Irganox 1010 (manufactured by BASF) as an antioxidant. 5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, to obtain a urethane adhesive solution. . Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (29). It was aged at room temperature for 5 days and evaluated.

[Example 30]
95 parts by weight of urethane prepolymer A, 3.5 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo), which is a polyol having three hydroxyl groups Kasei Co., Ltd., Mn = 3000) 1.5 parts by weight, 3.8 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, Fluorinated oligomer Megafac F-571 (DIC Corporation) ) 0.5 parts by weight, 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl)imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 as an antioxidant (manufactured by BASF) 0.5 parts by weight, Nasem ferric iron (manufactured by Nippon Kagaku Sangyo Co., Ltd.) 0.03 parts by weight as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, urethane A system adhesive solution was obtained. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (30). It was aged at room temperature for 5 days and evaluated.

[Example 31]
95 parts by weight of urethane prepolymer A, 3 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 2 parts by weight, 3.9 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl) imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 (manufactured by BASF) as an antioxidant ) 0.5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, and a urethane adhesive solution got Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (31). It was aged at room temperature for 5 days and evaluated.

[Example 32]
80 parts by weight of urethane prepolymer A, 12 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 8 parts by weight, 6.0 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl) imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 (manufactured by BASF) as an antioxidant ) 0.5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, and a urethane adhesive solution got Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (32). It was aged at room temperature for 5 days and evaluated.

[Example 33]
60 parts by weight of urethane prepolymer A, 28 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 12 parts by weight, 8.0 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl) imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 (manufactured by BASF) as an antioxidant ) 0.5 parts by weight, 0.03 parts by weight of Nasem ferric iron (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, and a urethane adhesive solution got Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (33). It was aged at room temperature for 5 days and evaluated.

[Example 34]
60 parts by weight of urethane prepolymer A, 25 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups 15 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 8.6 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.), a fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation), 0.5 parts by weight. 5 parts by weight, 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl) imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 (manufactured by BASF) as an antioxidant ) 0.5 parts by weight, 0.03 parts by weight of Nasem ferric iron (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, and a urethane adhesive solution got Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (34). It was aged at room temperature for 5 days and evaluated.

[Example 35]
50 parts by weight of urethane prepolymer A, 30 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP4000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=4000) 20 parts by weight, 8.7 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.50 parts by weight of 1-ethyl-3-methylimidazolium tri(fluoromethanesulfonyl) imide (AS110, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) as an ionic compound, Irganox 1010 (manufactured by BASF) as an antioxidant ) 0.5 parts by weight, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, diluted with ethyl acetate so that the total solid content is 50% by weight, and a urethane adhesive solution got Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (35). It was aged at room temperature for 5 days and evaluated.

[Comparative Example 1]
100 parts by weight of urethane prepolymer A, 3.2 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, as a catalyst , 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) and diluted with ethyl acetate so that the total solid content was 50% by weight, to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (C1). It was aged at room temperature for 5 days and evaluated.

[Comparative Example 2]
100 parts by weight of urethane prepolymer B, 2.9 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, as a catalyst , 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) and diluted with ethyl acetate so that the total solid content was 50% by weight, to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The faces were laminated to obtain a surface protective film (C2). It was aged at room temperature for 5 days and evaluated.

[Comparative Example 3]
50 parts by weight of urethane prepolymer A, 35 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups 15 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 9.2 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.), and a fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation) of 0.5 parts by weight. 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of Nasem ferric (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a substrate made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protective film (C3). It was aged at room temperature for 5 days and evaluated.

[Comparative Example 4]
50 parts by weight of urethane prepolymer A, 30 parts by weight of Preminol S3011 (manufactured by Asahi Glass Co., Ltd., Mn = 10000), which is a polyol having three hydroxyl groups, as a polyol, Sannics GP3000 (Sanyo Kasei Co., Ltd.), which is a polyol having three hydroxyl groups (Mn=3000) 20 parts by weight, 10.1 parts by weight of an isocyanate compound (Coronate HX: C/HX, manufactured by Nippon Polyurethane Co., Ltd.) as a cross-linking agent, 0.1 parts by weight of fluorine-based oligomer Megafac F-571 (manufactured by DIC Corporation). 5 parts by weight, 0.5 parts by weight of Irganox 1010 (manufactured by BASF) as an antioxidant, 0.03 parts by weight of ferric Nasem (manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst, and a total solid content of 50% by weight. was diluted with ethyl acetate to obtain a urethane adhesive solution. Then, the urethane-based adhesive solution was applied to a base material made of polyester resin (trade name “T100-75S”, thickness 75 μm, manufactured by Mitsubishi Chemical Corporation) so that the thickness after drying was 75 μm, and the drying temperature was 130 ° C. , and dried under the conditions of a drying time of 3 minutes to prepare a pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition. Next, on the surface of the obtained pressure-sensitive adhesive layer, a silicone-treated release liner (trade name: "MRF25", thickness: 25 μm, manufactured by Mitsubishi Chemical Corporation) made of polyester resin having a thickness of 25 μm and silicone-treated on one side was applied. The surfaces were laminated to obtain a surface protection film (C4). It was aged at room temperature for 5 days and evaluated.

[Examples 36 to 70]
For each of the surface protective films obtained in Examples 1 to 35, the release liner was peeled off, and a polarizing plate (trade name “TEG1465DUHC” manufactured by Nitto Denko Corporation), which is an optical member, was adhered, and the surface protective film was adhered. A coated optical member was obtained.

[Examples 71 to 105]
For each of the surface protective films obtained in Examples 1 to 35, the release liner was peeled off, and a conductive film (manufactured by Nitto Denko Co., Ltd., trade name “Elecrysta V270L-TFMP”) was attached to the surface. An electronic member to which the protective film was adhered was obtained.

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

REFERENCE SIGNS LIST 1 base layer 2 adhesive layer 10 surface protective film

Claims (11)

A surface protective film comprising an adhesive layer,
The pressure-sensitive adhesive layer is composed of a urethane-based pressure-sensitive adhesive formed from a urethane-based pressure-sensitive adhesive composition,
The urethane pressure-sensitive adhesive composition contains a base polymer and a fluorine-based compound,
the base polymer comprises a urethane prepolymer;
The proportion of hydroxyl groups contained in the urethane pressure-sensitive adhesive composition is less than 30 mmol relative to 100 g of the base polymer.
surface protection film. The surface protective film according to claim 1, wherein the base polymer contains a polyoxyalkylene structure represented by general formula (1).

(In general formula (1), R ¹ represents one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a hydroxyalkyl group having 1 to 6 carbon atoms. Multiple R ¹ may be the same or different, n represents an integer of 1 to 4, and m represents an integer of 1 to 200.) The surface protective film according to claim 2, wherein the urethane prepolymer contains a polyoxyalkylene structure represented by the general formula (1). 4. The surface protective film according to any one of claims 1 to 3, wherein said base polymer comprises a polyol, and said polyol is not a urethane prepolymer. The surface protection film according to claim 4, wherein the polyol contains a polyoxyalkylene structure represented by general formula (1).

(In general formula (1), R ¹ represents one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, and a hydroxyalkyl group having 1 to 6 carbon atoms. Multiple R ¹ may be the same or different, n represents an integer of 1 to 4, and m represents an integer of 1 to 200.) The surface according to claim 4 or 5, wherein the content ratio of the urethane prepolymer and the polyol in the urethane pressure-sensitive adhesive composition is urethane prepolymer: polyol = 70:30 to 100:0 by weight. Protective film. 7. The surface protection film according to any one of claims 1 to 6, wherein the pressure-sensitive adhesive layer has a haze of 3.5% or less. 8. The surface protective film according to any one of claims 1 to 7, wherein the fluorine-based compound has a surface tension of 23 mN/m or more in a 0.1% propylene glycol monomethyl ether solution. The surface protection film according to any one of claims 1 to 8, wherein the urethane pressure-sensitive adhesive composition contains 0.05 parts by weight or more of the ionic compound with respect to 100 parts by weight of the base polymer. An optical member to which the surface protection film according to any one of claims 1 to 9 is adhered. An electronic member to which the surface protection film according to any one of claims 1 to 9 is adhered.

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