KR101871743B1 - Release film for antistatic surface protection film - Google Patents

Abstract

The present invention provides an antistatic surface protective film which is less contaminated with an adherend and does not deteriorate with the passage of time and has excellent peeling electrification preventing performance. (D) a bifunctional or higher isocyanate compound, (E) a cross-linking accelerator, (F) a keto-enol A step of forming a pressure-sensitive adhesive layer (2) composed of a pressure-sensitive adhesive composition containing a tautomer compound and a releasing agent layer (4) containing an antistatic agent on one surface of the resin film (3) And a step of bonding the laminated release film (5) through the release agent layer (4) in this order. The release agent layer (4) comprises a release agent comprising dimethylpolysiloxane as a main component and a silicone A compound and an antistatic agent, and the peeling electrification voltage of the pressure-sensitive adhesive layer (2) is ± 0.6 kV or less.

Description

{RELEASE FILM FOR ANTISTATIC SURFACE PROTECTION FILM}

The present invention relates to a pressure-sensitive adhesive composition and a surface protective film. More particularly, the present invention relates to an antistatic surface protective film having antistatic properties. More specifically, the present invention provides a method for producing an antistatic surface protective film having low stain resistance to an adherend, and which does not deteriorate with time and has excellent peeling electrification preventing performance, and an antistatic surface protective film.

When manufacturing and transporting an optical product such as a polarizing plate, a retardation plate, a display lens film, an antireflection film, a hard coat film, a transparent conductive film for a touch panel, and a display using the same, And the surface protective film is laminated to prevent contamination and scratches on the surface in a subsequent step. The appearance inspection of the optically-usable film may be carried out in a state in which the surface-protective film is stuck to the optical film in order to eliminate the labor of peeling the surface-protective film and joining it again to improve the working efficiency.

Background Art [0002] Conventionally, a surface protective film having a pressure-sensitive adhesive layer formed on one surface of a base film is generally used to prevent scratches or contamination from adhering to the surface of a base film in the production process of optical products. The surface protective film is bonded to the optical film through a pressure sensitive adhesive layer. Adhesive strength of the pressure sensitive adhesive layer can be easily detached when the used surface protective film is peeled off from the surface of the optical film and the adhesive is not adhered to the optical film of the product So as to prevent the occurrence of so-called adhesive residue).

2. Description of the Related Art In recent years, in a production process of a liquid crystal display panel, a circuit component such as a driver IC for controlling a display screen of a liquid crystal display panel by a peeling electrification voltage generated when a surface protective film adhered on an optical film is peeled and removed And the phenomenon that the orientation of the liquid crystal molecules is damaged is small.

Further, in order to reduce the power consumption of the liquid crystal display panel, the driving voltage of the liquid crystal material is lowered, and accordingly the breakdown voltage of the driver IC is lowered. In recent years, it has been required to set the peeling electrification voltage within the range of +0.7 kV to -0.7 kV.

For this reason, in order to prevent a problem caused by a high peeling electrification voltage when peeling the surface protective film from the optical film to be peeled off, a surface protective film using a pressure sensitive adhesive layer containing an antistatic agent for suppressing the peeling electrification voltage Has been proposed.

For example, Patent Document 1 discloses a surface protective film using a pressure-sensitive adhesive composed of an alkyltrimethylammonium salt, a hydroxyl group-containing acrylic polymer, and a polyisocyanate.

Patent Document 2 discloses a pressure-sensitive adhesive composition comprising an ionic liquid and an acrylic polymer having an acid value of 1.0 or less, and pressure-sensitive adhesive sheets using the same.

Patent Document 3 discloses a pressure-sensitive adhesive composition comprising an alkali metal salt treated with an acrylic polymer, a polyether polyol compound, and an anion adsorptive compound, and a surface protective film using the same.

Patent Document 4 discloses a pressure-sensitive adhesive composition comprising an ionic liquid, an alkali metal salt, a polymer having a glass transition temperature of 0 ° C or lower, and a surface protective film using the pressure-sensitive adhesive composition.

Patent Documents 5 and 6 disclose mixing polyether-modified silicone in the pressure-sensitive adhesive layer of the surface protective film.

Japanese Patent Application Laid-Open No. 2005-131957 Japanese Laid-Open Patent Publication No. 2005-330464 Japanese Laid-Open Patent Publication No. 2005-314476 Japanese Laid-Open Patent Publication No. 2006-152235 Japanese Patent Application Laid-Open No. 2009-275128 Japanese Patent Publication No. 4537450

In the above Patent Documents 1 to 4, an antistatic agent is added to the pressure-sensitive adhesive layer. However, as the thickness of the pressure-sensitive adhesive layer becomes thicker and as time elapses, The amount of the antistatic agent transferred to the adherend increases. Further, in optical films such as LR (Low Reflective) polarizing plates and AG (Anti Glare) -LR polarizing plates, the surface of the optical film is treated with a silicone compound or a fluorine compound, The peeling electrification voltage is high when the protective film is peeled off from the optical film as the adhesion.

Further, when polyether-modified silicone is mixed in the pressure-sensitive adhesive layer described in Patent Documents 5 and 6, it is difficult to fine-tune the adhesive force of the surface protective film. Further, since the polyether-modified silicone is mixed in the pressure-sensitive adhesive layer, if the conditions for coating and drying the pressure-sensitive adhesive composition on the base film are changed, the surface characteristics of the pressure-sensitive adhesive layer on which the surface- Further, from the viewpoint of protecting the surface of the optical film, the thickness of the pressure-sensitive adhesive layer can not be made extremely thin. Therefore, it is necessary to increase the amount of the polyether-modified silicone to be mixed in the pressure-sensitive adhesive layer depending on the thickness of the pressure-sensitive adhesive layer. As a result, the adherend surface tends to be contaminated, Change.

2. Description of the Related Art In recent years, there has been an FPR (Film Patterned Retarder) film laminated on a surface of an optical film such as a polarizing plate in conjunction with the spread of a 3D display (stereoscopic display). The FPR film is bonded after peeling the surface protective film that has been adhered to the surface of the optical film such as a polarizing plate. However, if the surface of an optical film such as a polarizing plate is contaminated with a pressure-sensitive adhesive or an antistatic agent used in the surface protective film, there is a problem that the FPR film is difficult to adhere. For this reason, it is required that the surface protective film used in this application is less contaminated with the adherend.

On the other hand, in some liquid crystal panel manufacturers, as a method for evaluating the stain resistance of an adherend of a surface protective film, a surface protective film adhered to an optical film such as a polarizing plate is peeled once and the film is reattached in a state in which air bubbles are mixed A heat treatment is performed under a predetermined condition, and then the surface protective film is peeled off to observe the surface of the adherend. In this evaluation method, even if the surface contamination of the adherend is minute, if there is a difference in surface contamination of the adherend at the portion where the air bubbles are mixed and the surface protective film is in contact with the pressure sensitive adhesive, there may be a trace of air bubbles ). Therefore, the evaluation method of the stain on the surface of the adherend is a very strict evaluation method. In recent years, there has been a demand for a surface protective film which does not cause contamination on the surface of an adherend even when the result of the determination is determined by such a strict evaluation method. However, the surface protective film using the pressure-sensitive adhesive layer containing a conventionally proposed antistatic agent has been difficult to solve the problems.

For this reason, it is required that the surface protective film used for the optical film has very little contamination on the adherend, and that the stain resistance to the adherend does not change over time. In addition, there is a demand for a surface protective film in which the peeling electrification voltage is lowered when peeling off from an adherend.

The present inventors have conducted extensive studies to solve this problem.

It is necessary to reduce the addition amount of the antistatic agent, which is presumed to be a cause of contaminating the adherend, in order to reduce contamination to the adherend and to reduce the change with time of the antistatic performance. However, when the addition amount of the antistatic agent is reduced, the peeling electrification voltage when peeling the surface protective film from the adherend becomes high. The present inventors have studied a method of suppressing the peeling electrification voltage when the surface protective film is peeled from the adherend without increasing the absolute amount of the antistatic agent added. As a result, it has been found that, instead of adding an antistatic agent into the pressure-sensitive adhesive composition and mixing them to form a pressure-sensitive adhesive layer, the pressure-sensitive adhesive composition is coated and dried to laminate the pressure- It is possible to suppress the peeling electrification voltage when the film is peeled off from the optically-usable film as the adherend, thereby completing the present invention.

An object of the present invention is to provide an antistatic surface protective film which has less stain on an adherend, does not deteriorate with time, and has excellent peeling electrification preventing performance.

In order to solve the above problems, the antistatic surface protective film of the present invention is produced by laminating a pressure-sensitive adhesive composition by coating and drying the pressure-sensitive adhesive composition, and then applying a silicone compound and an antistatic agent It is possible to reduce the peeling electrification voltage at the time of peeling from the optical film as the adherend while suppressing the staining property to the adherend to a low level.

In order to solve the above problems, the present invention provides an antistatic surface protective film comprising the following steps (1) to (2)

Process (1): A process for producing a film comprising a base film made of a resin having transparency, comprising the steps of: (A) mixing at least one (meth) acrylic ester monomer having an alkyl group of C4 to C18 in an alkyl group (B) a copolymerizable monomer containing a hydroxyl group and (C) a copolymerizable monomer group comprising a nitrogen-containing vinyl monomer or an alkoxy group-containing alkyl (meth) acrylate monomer not containing a hydroxyl group A pressure-sensitive adhesive composition comprising a pressure-sensitive adhesive composition comprising an acrylic polymer of at least one selected copolymer and further comprising (D) an isocyanate compound having two or more functional groups, (E) a crosslinking accelerator, and (F) A step of forming a layer,

Step (2): a step of, on the surface of the pressure-sensitive adhesive layer, a step of adhering a release film having a release agent layer containing an antistatic agent on one side of the resin film laminated via the release agent layer in this order, Wherein the releasing agent layer is formed of a releasing agent comprising dimethylpolysiloxane as a main component, a silicone compound as a liquid at 20 占 폚 and a resin composition containing the antistatic agent, wherein the peeling electrification voltage of the pressure- Resistant surface protective film.

In addition, it is preferable to further include (G) a polyalkylene glycol mono (meth) acrylate monomer as the copolymerizable monomer group.

The crosslinking accelerator (E) is preferably at least one selected from the group consisting of an aluminum chelate compound, a titanium chelate compound and an iron chelate compound.

Further, the copolymerizable monomer (B) containing a hydroxyl group is preferably selected from the group consisting of 8-hydroxyoctyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 4-hydroxybutyl At least one compound selected from the group consisting of N-hydroxyethyl (meth) acrylate, N-hydroxy (meth) acrylamide, N-hydroxymethyl (meth) acrylamide and N-hydroxyethyl desirable.

Also, when the (meth) acrylate monomer is a polyalkylene glycol mono (meth) acrylate, the methoxy polyalkylene glycol (meth) acrylate, the ethoxy polyalkylene glycol (meth) Acrylate, and the like.

The bifunctional isocyanate compound (D) as the bifunctional or higher functional isocyanate compound is a compound produced by reacting a diisocyanate compound with a diol compound as an alicyclic aliphatic isocyanate compound. Examples of the diisocyanate compound include aliphatic diisocyanate compounds, Methyl-1, 3-propanediol, 2-methyl-1, 3-propanediol, 2-methyl-1,3-propanediol, and 2-methyl-1,3-propanediol, and a diol compound selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, Propylene-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 3-methyl- - pentanediol, 2,2-dimethyl-1,3-propanediol monohydroxypivalate, polyethylene glycol, and polypropylene glycol. Examples of the trifunctional isocyanate compound include an isocyanurate compound of a hexamethylene diisocyanate compound, an isocyanurate compound of an isophorone diisocyanate compound, an adduct of an hexamethylene diisocyanate compound, an isophorone compound of an isophorone An isocyanurate compound of a tolylene diisocyanate compound, an isocyanurate compound of a xylylene diisocyanate compound, an isocyanurate compound of a xylylene diisocyanate compound, an isocyanurate compound of a xylylene diisocyanate compound, an isocyanurate compound of a xylylene diisocyanate compound, An isocyanurate of a xylylene diisocyanate compound, an adduct of a tolylene diisocyanate compound, an adduct of a xylylene diisocyanate compound, and an adduct of a hydrogenated xylylene diisocyanate compound.

It is also preferable that the pressure-sensitive adhesive composition contains a polyether-modified siloxane compound having an HLB value of 7 to 15 (H).

The silicone compound in the release agent layer is preferably polyether-modified silicone.

It is preferable that the antistatic agent in the releasing agent layer is an alkali metal salt.

In order to solve the above-described problems, the present invention relates to a method for producing a (meth) acrylate-based polymer film, which comprises: (A) (B) a copolymerizable monomer containing a hydroxyl group, and (C) a nitrogen-containing vinyl monomer or alkoxy group-containing alkyl (meth) acrylate monomer containing no hydroxyl group , Wherein a release agent layer containing an antistatic agent is laminated on one surface of a resin film on the surface of the pressure-sensitive adhesive layer, and a pressure-sensitive adhesive layer of an acrylic polymer comprising at least one copolymer selected from the group consisting of Wherein a release film is laminated on the release agent layer via the release agent layer, And that the dimethylpolysiloxane as a main component release agent, is formed of a resin composition comprising a liquid silicone compound and an antistatic agent at 20 ℃ provides made antistatic surface protecting film.

In addition, it is preferable to further include (G) a polyalkylene glycol mono (meth) acrylate monomer as the copolymerizable monomer group.

The silicone compound in the release agent layer is preferably polyether-modified silicone.

It is preferable that the antistatic agent in the releasing agent layer is an alkali metal salt.

The present invention also provides an optical film in which the antistatic surface protective film is bonded.

The present invention also provides an optical component in which the antistatic surface protective film is bonded.

The antistatic surface protective film of the present invention has little fouling on the adherend, and does not change the stain on the adherend over time. Further, according to the present invention, even when the surface of an adherend, such as an LR polarizing plate or an AG-LR polarizing plate, is an optical film having an anti-fouling treatment with a silicone compound, a fluorine compound or the like, when an antistatic surface protective film is peeled from an adherend It is possible to provide an antistatic surface protective film having a peeling electrification preventing performance which can suppress the generated peeling electrification voltage to a low level and does not deteriorate with time.

According to the antistatic surface protective film of the present invention, productivity can be improved and yield can be improved because the surface of the optical film can be reliably protected.

1 is a cross-sectional view showing the concept of an antistatic surface protective film of the present invention.
2 is a cross-sectional view showing a state in which a release film is peeled from an antistatic surface protective film of the present invention.
3 is a cross-sectional view showing one embodiment of the optical component of the present invention.

Hereinafter, the present invention will be described in detail based on embodiments.

1 is a cross-sectional view showing the concept of an antistatic surface protective film of the present invention. In this antistatic surface protective film 10, a pressure-sensitive adhesive layer 2 is formed on the surface of one side of the transparent base film 1. On the surface of the pressure-sensitive adhesive layer (2), a release film (5) having a release agent layer (4) formed on the surface of the resin film (3) is bonded.

As the base film (1) used in the antistatic surface protective film (10) according to the present invention, a base film made of a resin having transparency and flexibility is used. Thus, the appearance of the optical component can be inspected with the antistatic surface protective film adhered to the optical component as the adherend. A film made of a resin having transparency used as the base film (1) is preferably a polyester film such as polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate or polybutylene terephthalate. In addition to the polyester film, films made of other resins can be used as long as they have the necessary strength and optical suitability. The base film (1) may be a non-oriented film or a uniaxially or biaxially oriented film. Further, the stretching magnification of the stretched film or the orientation angle of the axial method formed by crystallization of the stretched film may be controlled to a specific value.

The thickness of the base film (1) used in the antistatic surface protective film (10) according to the present invention is not particularly limited. For example, the thickness is preferably about 12 to 100 mu m, more preferably about 20 to 50 mu m It is easier to handle and more preferable.

If necessary, an antifouling layer, antistatic layer, anti-scratch hard coat layer, or the like for preventing surface contamination can be formed on the surface of the base film 1 opposite to the surface on which the pressure-sensitive adhesive layer 2 is formed. Further, the surface of the base film 1 may be subjected to easy adhesion treatment such as surface modification by corona discharge, application of an anchor coat, and the like.

The pressure-sensitive adhesive layer (2) used in the antistatic surface protective film (10) according to the present invention is a pressure-sensitive adhesive which is adhered to the surface of an adherend and is easily peeled off after use, Although not limited, it is general to use an acrylic pressure-sensitive adhesive obtained by crosslinking a (meth) acrylate copolymer in view of durability after bonding to an optical film.

Particularly, the acrylic pressure-sensitive adhesive does not contain a copolymerizable monomer containing a carboxyl group as a copolymerizable monomer group with at least one of (A) a (meth) acrylic acid ester monomer having an alkyl group of C4 to C18 in the alkyl group, (Meth) acrylate monomer containing a nitrogen-containing vinyl monomer or an alkoxy group-containing monomer having no hydroxyl group, and (C) at least one copolymer selected from the group consisting of a copolymerizable monomer A pressure-sensitive adhesive layer is preferable.

(G) a polyalkylene glycol mono (meth) acrylic acid ester monomer as the copolymerizable monomer group.

Further, a pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive composition containing (D) a bifunctional or higher isocyanate compound, (E) a crosslinking accelerator and (F) a ketoene aliphatic tautomer compound is preferably added to the acrylic polymer.

Examples of the (meth) acrylic acid ester monomer (A) in which the alkyl group has 4 to 18 carbon atoms include butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (Meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (Meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (Meth) acrylate, heptadecyl (meth) acrylate, octadecyl (meth) acrylate, myristyl (meth) acrylate, isomyristyl Cetyl (meth) acrylate Sites, and the like can be mentioned stearyl (meth) acrylate, isostearyl (meth) acrylate.

It is preferable that (A) the (meth) acrylic acid ester monomer having an alkyl group of C4 to C18 is contained in an amount of 50 to 95 parts by weight, when the total amount of the acrylic polymer of the copolymer is 100 parts by weight.

Examples of the copolymerizable monomer containing a hydroxyl group (B) include a copolymerizable monomer having a hydroxyl group such as 8-hydroxyoctyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 4-hydroxybutyl (meth) (Meth) acrylate such as ethyl (meth) acrylate, N-hydroxy (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N-hydroxyethyl (Meth) acrylamides containing hydroxyl groups.

(Meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, N-hydroxy ) Acrylamide, N-hydroxymethyl (meth) acrylamide and N-hydroxyethyl (meth) acrylamide.

When the total amount of the acrylic polymer of the copolymer is 100 parts by weight, it is preferable that the copolymerizable monomer containing the hydroxyl group (B) is contained in a proportion of 0.1 to 10 parts by weight.

It is preferable that the acryl-based polymer includes at least one or more of a nitrogen-containing vinyl monomer (C) containing no hydroxyl group or an alkyl (meth) acrylate monomer containing an alkoxy group as the copolymerizable monomer group.

Examples of the nitrogen-containing vinyl monomer (C-1) in the component (C) include a vinyl monomer containing an amide bond, a vinyl monomer containing an amino group, and a vinyl monomer having a nitrogen-containing heterocyclic structure. More specifically, there may be mentioned N-vinyl-2-pyrrolidone, N-vinylpyrrolidone, methylvinylpyrrolidone, N- vinylpyridine, N-vinylpiperidone, N- vinylpyrimidine, Substituted vinyls such as N-vinylpyrroles, N-vinylpyrroles, N-vinylimidazoles, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, N- A cyclic nitrogen vinyl compound having a heterocyclic structure; (Meth) acryloyl morpholine, N- (meth) acryloylpiperazine, N- (meth) acryloyl aziridine, N- (meth) acryloyl azetidine, N- (Meth) acryloyl-substituted (meth) acryloyl groups such as N- (meth) acryloylpiperidine, N- A cyclic nitrogen vinyl compound having a heterocyclic structure; A cyclic nitrogen vinyl compound having a heterocyclic structure having a nitrogen atom such as N-cyclohexylmaleimide or N-phenylmaleimide and an ethylenically unsaturated bond in the ring; Unsubstituted or monoalkyl-substituted (meth) acrylamides such as N-methyl (meth) acrylamide, N-methyl (meth) acrylamide, N-isopropyl (meth) acrylamide and Nt-butyl (meth) acrylamide; (Meth) acrylamide, N, N-diethyl (meth) acrylamide, N, (Meth) acrylamide, N-methyl-N-methyl (meth) acrylamide, N-methyl- Substituted (meth) acrylamides; N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, (Meth) acrylate, N, N-dimethylaminobutyl (meth) acrylate, N, N-diethylaminomethyl (Meth) acrylate, N, N-dibutylaminoethyl (meth) acrylate, N, N-dimethylaminoethyl (Meth) acrylate, t-butylaminoethyl (meth) acrylate and the like; N, N-diethylaminopropyl (meth) acrylamide, N, N-dipropylaminopropyl (meth) acrylamide, N, N-diisopropylaminopropyl (Meth) acrylamide, N-methyl-N-isopropylaminopropyl (meth) acrylamide, N-methyl- N, N-dialkyl-substituted aminopropyl (meth) acrylamides such as amides; N-vinylcarboxylic acid amides such as N-vinyl formamide, N-vinylacetamide and N-vinyl-N-methylacetamide; (Meth) acrylamide, N, N-methylenebis (meth) acrylamide, and the like can be used in combination with one or more of N-methoxymethyl (meth) acrylamide, N-ethoxyethyl (Meth) acrylamides; Unsaturated carboxylic acid nitriles such as (meth) acrylonitrile; And the like.

The nitrogen-containing vinyl monomer (C-1) is preferably a compound containing no hydroxyl group, more preferably a compound containing no hydroxyl group and no carboxyl group. Examples of such monomers include acrylic monomers containing the above-exemplified monomers, for example, N, N-dialkyl substituted amino groups and N, N-dialkyl substituted amide groups; Vinyl-substituted lactams such as N-vinyl-2-pyrrolidone, N-vinylcaprolactam and N-vinyl-2-piperidone; N- (meth) acryloyl-substituted cyclic amines such as N- (meth) acryloylmorpholine and N- (meth) acryloylpyrrolidine are preferred.

(Meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-propoxyethyl (meth) acrylate and the like can be given as examples of the alkyl (meth) (Meth) acrylate, 2-ethoxypropyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, 2- (Meth) acrylate, 2-propoxypropyl (meth) acrylate, 2-isopropoxypropyl (meth) acrylate, 2-butoxypropyl Propyl (meth) acrylate, 3-butoxypropyl (meth) acrylate, 4-methoxybutyl (meth) acrylate, Acrylate, 4-ethoxybutyl (meth) acrylate, 4-propoxybutyl (meth) acrylate, 4-isopropoxybutyl And the like methacrylate, 4-butoxy-butyl (meth) acrylate.

These alkoxy group-containing alkyl (meth) acrylate monomers have a structure in which the atom of the alkyl group in the alkyl (meth) acrylate is substituted with an alkoxy group.

(C-1) a nitrogen-containing vinyl monomer containing no hydroxyl group or an alkyl (meth) acrylate monomer containing a (C-2) alkoxy group in an amount of 0 to 20 parts by weight based on 100 parts by weight of the total of the acrylic polymer By weight. (C-1) a nitrogen-containing vinyl monomer containing no hydroxyl group and an alkyl (meth) acrylate monomer containing (C-2) an alkoxy group may be used alone or in combination of two or more. In the pressure-sensitive adhesive layer according to the present invention, a nitrogen-containing vinyl monomer (C) containing no hydroxyl group or an alkyl (meth) acrylate monomer containing an alkoxy group may not be contained in the pressure-sensitive adhesive composition.

As the bifunctional or higher functional isocyanate compound (D), at least one selected from polyisocyanate compounds having at least two isocyanate (NCO) groups in one molecule may be used. The polyisocyanate compound may be classified into an aliphatic isocyanate, an aromatic isocyanate, a non-glycidic isocyanate, and an alicyclic isocyanate. Specific examples of the polyisocyanate compound include aliphatic isocyanate compounds such as hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and trimethylhexamethylene diisocyanate (TMDI), diphenylmethane diisocyanate (MDI) Aromatic isocyanate compounds such as xylylene diisocyanate (XDI), hydrogenated xylylene diisocyanate (H6XDI), dimethyldiphenylenediisocyanate (TOID), and tolylene diisocyanate (TDI).

Examples of the trifunctional or higher isocyanate compound include buret-modified or isocyanurate-modified bifunctional isocyanate compounds (compounds having two NCO groups in one molecule), trimethylolpropane (TMP), tri- or higher-valent polyols such as glycerin And an adduct (polyol modified product) with a compound having at least three OH groups in the molecule).

It is also possible to use only (D-1) a trifunctional isocyanate compound or (D-2) a bifunctional isocyanate compound as the (D) bifunctional or higher isocyanate compound. It is also possible to use the (D-1) trifunctional isocyanate compound and the (D-2) bifunctional isocyanate compound in combination.

Examples of the (D-1) trifunctional isocyanate compound used in the present invention include isocyanurate compounds of hexamethylene diisocyanate compounds, isocyanurate compounds of isophorone diisocyanate compounds, and compounds of hexamethylene diisocyanate compounds At least one member selected from the group of the first aliphatic isocyanate compounds (D-1-1), which is a duct body, an adduct of an isophorone diisocyanate compound, a burette of a hexamethylene diisocyanate compound, and a burette of an isophorone diisocyanate compound, An isocyanurate of a tolylene diisocyanate compound, an isocyanurate of a xylenediisocyanate compound, an isocyanurate of a hydrogenated xylylene diisocyanate compound, an adduct of a tolylene diisocyanate compound, The adducts, number of isocyanate compounds And at least one selected from the group of the second aromatic isocyanate compounds (D-1-2), which is an adduct of an adduct of an indolylene diisocyanate compound. (D-1-1) The first aliphatic isocyanate compound group and (D-1-2) second aromatic isocyanate compound group are preferably used in combination. In the present invention, at least one kind selected from the group (D-1-1) of the first aliphatic isocyanate compounds and (D-1-2) the second aromatic isocyanate compound group as the (D-1) trifunctional isocyanate compound By using at least one selected in combination, it is possible to further improve the adhesive force balance between the low-speed peeling area and the high-speed peeling area.

The trifunctional isocyanate compound (D-1) is at least one selected from the group of the first aliphatic isocyanate compounds (D-1-1), the second aromatic isocyanate compound group (D-1-2) , And preferably 0.5 to 5.0 parts by weight, based on 100 parts by weight of the copolymer. The mixing ratio of at least one selected from the group consisting of the first aliphatic isocyanate compound group (D-1-1) and the second aromatic isocyanate compound group (D-1-2) is (D- 1-1) :( D-1-2) in a weight ratio of 10%: 90% to 90%: 10%.

The (D-2) bifunctional isocyanate compound to be used in the present invention is preferably an alicyclic aliphatic isocyanate compound which is produced by reacting a diisocyanate compound with a diol compound.

For example, the diisocyanate compound may be represented by the formula " HO-Y-OH " (where Y is divalent) with the formula " O = C = NXN = C = O " , A compound produced by reacting a diisocyanate compound with a diol compound includes, for example, a compound represented by the following formula (Z).

(Z)

O = C = NX- (NH-CO-OYO-CO-NH-X) _n -N = C = O

Here, n is an integer of 0 or more. When n is 0, the formula Z represents " O = C = N-X-N = C = O ". As the bifunctional aliphatic isocyanate compound, a compound wherein n is 0 in the formula (Z) (diisocyanate compound unreacted with respect to the diol compound) may be contained, but it is preferable that the compound contains n as an essential component. The bifunctional aliphatic isocyanate compound may be a mixture of a plurality of compounds in which n in the general formula (Z) is different.

The diisocyanate compound represented by the chemical formula "O = C = N-X-N = C = O" is an aliphatic diisocyanate. X is a non-cyclic, aliphatic divalent radical. The aliphatic diisocyanate is preferably one or more selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and lysine diisocyanate.

The diol compound represented by the formula " HO-Y-OH " is an aliphatic diol. Y is preferably a divalent aliphatic divalent non-cyclic. Examples of the diol compound include 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, Methyl-1,5-pentanediol, 2,2-dimethyl-1,3-propanediol monohydroxy pivalate, polyethylene glycol, and polypropylene glycol. It is preferable that it is composed of one kind or two kinds or more selected.

The weight ratio (D-1 / D-2) of the (D-1) trifunctional isocyanate compound to the (D-2) bifunctional isocyanate compound is preferably 1 to 90. It is preferable that the isocyanate compound (D) having a bifunctionality or higher is 0.1 to 10 parts by weight based on 100 parts by weight of the acryl-based polymer.

When the polyisocyanate compound (E) is used as a crosslinking agent, the crosslinking accelerator (E) may be any substance that functions as a catalyst for the reaction (crosslinking reaction) between the copolymer and the crosslinking agent, and may be an amine compound such as a tertiary amine, , Organic tin compounds, organic lead compounds, organic zinc compounds and the like. In the present invention, a metal chelate compound or an organotin compound is preferably used as a crosslinking accelerator.

The metal chelate compound is a compound in which one or more Dazoid ligands L are bonded to the central metal atom M. The metal chelate compound may or may not have at least one monocyclic ligand X bonded to the metal atom M. For example, when the chemical formula of a metal chelate compound having one metal atom M is represented by M (L) _m (X) _n , _m? 1, _n ? When m is 2 or more, m Ls may be the same ligand or different ligands. When n is 2 or more, n Xs may be the same ligand or different ligands.

Examples of the metal atom M include Fe, Ni, Mn, Cr, V, Ti, Ru, Zn, Al, Zr and Sn.

Examples of the polycondensate L include β-keto esters such as methyl acetoate, ethyl acetoate, octyl acetoate, oleyl acetoate, lauryl acetoacetate, and stearyl acetoate, acetyl acetone (also called 2,4-pentanedione) , 2,4-hexanedione, and benzoyl acetone. These are keto enol tautomeric compounds, and for the polydentate ligands L, enol may be a deprotonated enolate (for example, acetylacetonate).

Examples of the monocyclic ligand X include acyloxys such as a halogen atom such as a chlorine atom and a bromine atom, a pentanoyl group, a hexanoyl group, a 2-ethylhexanoyl group, an octanoyl group, a nonanoyl group, a decanoyl group, a dodecanoyl group, A methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, and a butoxy group.

Specific examples of the metal chelate compound include tris (2,4-pentanedionate) iron (III), iron trisacetylacetonate, titanium trisacetylacetonate, ruthenium trisacetylacetonate, zinc bisacetylacetonate, aluminum tris (2,4-hexanedionate) iron (III), bis (2,4-hexanedionate) zinc, tris (2,4-hexanedionate) titanium, Tris (2,4-hexanedionate) aluminum, tetrakis (2,4-hexanedionate) zirconium, and the like.

Examples of the organotin compounds include dialkyltin oxide, dialkyltin fatty acid salts, and stannous primary fatty acid salts. Conventionally, dibutyltin compounds have been widely used. However, recently, toxicity problems of organotin compounds have been pointed out. In particular, tributyltin (TBT) contained in dibutyltin compounds is also considered as an endocrine disruptor. From the viewpoint of safety, long-chain alkyltin compounds such as dioctyltin compounds are preferable. Specific organic tin compounds include dioctyltin oxide, dioctyltin dilaurate and the like. Although Sn compounds may be used as a matter of fact, in the future, it is desirable to use metal chelate compounds such as Al, Ti, Fe, etc., which are more safe than Sn, in view of the trend of using a material having higher safety desirable.

The crosslinking accelerator (E) in the pressure-sensitive adhesive composition according to the present invention is preferably at least one selected from the group consisting of an aluminum chelate compound, a titanium chelate compound and an iron chelate compound.

The crosslinking accelerator (E) is preferably contained in an amount of 0.001 to 0.5 parts by weight based on 100 parts by weight of the copolymer.

(F) Examples of the ketoene aliphatic tautomer compound include? -Keto esters such as methyl acetoate, ethyl acetoate, octyl acetoate, oleyl acetoacetate, lauryl acetoacetate and stearyl acetoate, acetyl acetone, 2 , 4-hexanedione, and benzoyl acetone. In these pressure-sensitive adhesive compositions using a polyisocyanate compound as a cross-linking agent, blocking of an isocyanate group contained in the cross-linking agent can suppress the increase in the excess viscosity or gelation of the pressure-sensitive adhesive composition after compounding the cross-linking agent and prolong the pot life of the pressure-sensitive adhesive composition.

(F) The ketoene tautomer compound is preferably contained in an amount of 0.1 to 200 parts by weight based on 100 parts by weight of the copolymer.

(F) The ketoene tautomer compound (E) has an effect of inhibiting the crosslinking as opposed to the crosslinking accelerator (E), and the ratio of the ketoene enolymide compound (F) to the crosslinking accelerator . In order to lengthen the pot life of the pressure-sensitive adhesive composition and improve the storage stability, the weight ratio of (E) :( F) is preferably in the range of 1: 1 to 1: 500, more preferably 1: : 500, and most preferably from 1:80 to 1: 500.

The acryl-based polymer may optionally contain (G) a polyalkylene glycol mono (meth) acrylate monomer as the copolymerizable monomer group. (G) The polyalkylene glycol mono (meth) acrylic acid ester monomer may be any of a plurality of hydroxyl groups of the polyalkylene glycol, one of which is esterified as a (meth) acrylic acid ester. (Meth) acrylic acid ester group becomes a polymerizable group, it can be copolymerized with the subject polymer. The other hydroxyl group may be the same as OH, or may be an alkyl ether such as methyl ether or ethyl ether, or a saturated carboxylic acid ester such as acetic acid ester.

Examples of the alkylene group of the polyalkylene glycol include an ethylene group, a propylene group, and a butylene group, but are not limited thereto. The polyalkylene glycol may be a copolymer of two or more polyalkylene glycols such as polyethylene glycol, polypropylene recol, and polybutylene glycol. Examples of the copolymer of polyalkylene glycol include polyethylene glycol-polypropylene glycol, polyethylene glycol-polybutylene glycol, polypropylene glycol-polybutylene glycol, and polyethylene glycol-polypropylene glycol-polybutylene glycol. The copolymer may be a block copolymer or a random copolymer.

(G) polyalkylene glycol mono (meth) acrylic acid ester monomer preferably has 3 to 14 average number of repeating alkylene oxides constituting the polyalkylene glycol chain. The "average number of repeating alkylene oxides" refers to the number of repeating units in the "polyalkylene glycol chain" part of the molecular structure of the polyalkylene glycol mono (meth) acrylate monomer (G) It is the average number.

Examples of the (G) polyalkylene glycol mono (meth) acrylate monomer include polyalkylene glycol mono (meth) acrylate, methoxypolyalkylene glycol (meth) acrylate, ethoxypolyalkylene glycol And at least one selected from the group consisting of:

More specifically, there may be mentioned polyolefin such as polyethylene glycol-mono (meth) acrylate, polypropylene glycol-mono (meth) acrylate, polybutylene glycol- mono (meth) acrylate, polyethylene glycol-polypropylene glycol- Poly (ethylene glycol) -polybutylene glycol-mono (meth) acrylate, polypropylene glycol-polybutylene glycol-mono (meth) acrylate, polyethylene glycol-polypropylene glycol- Rate; Methoxypolyethylene glycol- (meth) acrylate, methoxypolyethylene glycol- (meth) acrylate, methoxypolypropylene glycol- (meth) acrylate, methoxypolybutylene glycol- (meth) acrylate, methoxypolyethylene glycol- (Meth) acrylate, methoxy-polyethylene glycol-polybutylene glycol- (meth) acrylate, methoxypolypropylene glycol-polybutylene glycol- (meth) acrylate, methoxy-polyethylene glycol-polypropylene glycol-polybutylene Glycol - (meth) acrylate; Acrylate, ethoxypolyethylene glycol- (meth) acrylate, ethoxypolyethylene glycol- (meth) acrylate, ethoxypolypropylene glycol- (meth) acrylate, ethoxypolybutylene glycol- (Meth) acrylate, ethoxy-polyethylene glycol-polybutylene glycol- (meth) acrylate, ethoxy-polypropylene glycol-polybutylene glycol- Glycol- (meth) acrylate, and the like.

(Meth) acrylic acid ester monomer (G) in a proportion of 0 to 50 parts by weight, when the total amount of the acrylic polymer of the copolymer is 100 parts by weight. In the pressure-sensitive adhesive layer according to the present invention, the (G) polyalkylene glycol mono (meth) acrylic acid ester monomer may not be contained in the pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition may optionally contain (H) a polyether-modified siloxane compound. (H) a polyether-modified siloxane compound is a siloxane compound having a polyether, a typical siloxane unit [-SiR ¹ ₂ -O-] In addition, the siloxane units having polyether ^{[-SiR 1 (R 2 O (} R 3 O ) _n R ⁴ ) -O-]. (Wherein R ¹ represents one or two or more kinds of alkyl groups or aryl groups, R ² and R ³ represent one or two or more kinds of alkylene groups, and R ⁴ represents one or two or more kinds of alkyl groups or acyl groups . Examples of the polyether group include polyoxyalkylene groups such as polyoxyethylene group [(C ₂ H ₄ O) _n ] and polyoxypropylene group [(C ₃ H ₆ O) _n ].

(H) The polyether-modified siloxane compound is preferably a polyether-modified siloxane compound having an HLB value of 7 to 15. It is also preferable that 0.01 to 1.0 part by weight of the polyether-modified siloxane compound (H) is contained relative to 100 parts by weight of the copolymer. More preferably 0.1 to 0.5 parts by weight.

HLB is a hydrophilic lipophilic balance (hydrophilic lipophilic ratio) defined by, for example, JIS K3211 (surfactant term).

(H) The polyether-modified siloxane compound can be obtained, for example, by grafting an organic compound having an unsaturated bond and a polyoxyalkylene group to a polyorganosiloxane main chain having a hydrogenated silicon group by a hydrosilylation reaction. Specific examples thereof include dimethylsiloxane · methyl (polyoxyethylene) siloxane copolymer, dimethylsiloxane · methyl (polyoxyethylene) siloxane · methyl (polyoxypropylene) siloxane copolymer, dimethylsiloxane · methyl (polyoxypropylene) .

(H) The polyether-modified siloxane compound is compounded in the pressure-sensitive adhesive composition, whereby the pressure-sensitive adhesive and the pressure-sensitive adhesive can be improved. When the pressure-sensitive adhesive composition does not contain a polyether-modified siloxane compound, it becomes more inexpensive.

Further, it is also possible to use other components such as a copolymerizable (meth) acrylic monomer, a (meth) acrylamide monomer, a dialkyl substituted acrylamide monomer, a surfactant, a curing accelerator, a plasticizer, a filler, , An antioxidant, and an antioxidant may be appropriately added. These may be used alone or in combination of two or more.

The subject copolymer used in the pressure-sensitive adhesive composition of the present invention is a monomer copolymerizable with at least one of (A) a (meth) acrylic acid ester monomer having an alkyl group of C4 to C18 in number, and (B) (C) at least one selected from the group consisting of a nitrogen-containing vinyl monomer containing no hydroxyl group or an alkyl (meth) acrylate monomer containing an alkoxy group. (G) polyalkylene glycol mono (meth) acrylic acid ester monomer as the copolymerizable monomer group. The polymerization method of the copolymer is not particularly limited, and suitable polymerization methods such as solution polymerization, emulsion polymerization and the like can be used.

The pressure-sensitive adhesive composition of the present invention can be prepared by blending (D) a bifunctional or higher isocyanate compound, (E) a crosslinking accelerator, (F) a ketoene aliphatic tautomer compound and further optionally an optional additive .

The copolymer is preferably an acrylic polymer, and it is preferable that the copolymer contains 50 to 100% by weight of an acrylic monomer such as (meth) acrylate monomer, (meth) acrylic acid or (meth) acrylamide.

Since the acryl-based polymer does not contain a copolymerizable monomer containing a carboxyl group as a copolymerizable monomer group, it is effective in improving the crosslinking speed and stabilizing the adhesive force. It is preferable to use a copolymerizable monomer containing a hydroxyl group (B) as a monomer which reacts with the isocyanate compound (D) having two or more functional groups used as a crosslinking agent. The copolymer preferably has at least one monomer composition from (A) and (B), at least one monomer from each of (A), (B) and (C) At least one kind selected from (B) and (G), and at least one kind selected from (A), (B), (C) and (G).

It is preferable that the pressure-sensitive adhesive layer formed by crosslinking the pressure-sensitive adhesive composition has an adhesive force of 0.05 to 0.1 N / 25 mm at a low speed peeling speed of 0.3 m / min and an adhesive force of 1.0 N / 25 mm or less at a high speed peeling speed of 30 m / . As a result, it is possible to obtain a performance in which the adhesive force does not change even by the peeling speed, and it is possible to peel quickly even by high-speed peeling. In addition, in order to reattach it, an excessive force is not necessary even once the surface protective film is peeled, and it is easy to peel off from the adherend.

It is preferable that the pressure-sensitive adhesive layer formed by crosslinking the pressure-sensitive adhesive composition has a surface resistivity of 5.0 x 10 ^{+ 12} ? /? Or less and a peeling electrification voltage of? 0.6 kV or less. In the present invention, "± 0.6 kV or less" means 0 to -0.6 kV and 0 to + 0.6 kV, that is, -0.6 to +0.6 kV. When the surface resistivity is high, the performance for escaping the static electricity generated by the charging at the time of peeling is lowered. Therefore, by sufficiently reducing the surface resistivity, the peeling electrification voltage caused by the static electricity generated when the adherend is peeled off is reduced Thus, it is possible to suppress the influence on the electric control circuit of the adherend or the like.

The gel fraction of the pressure-sensitive adhesive layer (pressure-sensitive adhesive after crosslinking) obtained by crosslinking the pressure-sensitive adhesive composition of the present invention is preferably 95 to 100%. As described above, the high gel fraction lowers the adhesive force at a low rate of peeling, reduces elution of the unpolymerized monomer or oligomer from the copolymer, and improves the reworkability and durability at high temperature and high humidity, The contamination of the complex can be suppressed.

The pressure-sensitive adhesive film of the present invention is formed by forming a pressure-sensitive adhesive layer formed by crosslinking the pressure-sensitive adhesive composition of the present invention on one side or both sides of a resin film. The surface protective film of the present invention is a surface protective film comprising a pressure-sensitive adhesive layer formed by crosslinking the pressure-sensitive adhesive composition of the present invention on one side of a resin film. Since the pressure-sensitive adhesive composition of the present invention has the components (A) to (F) in a well-balanced manner, the pressure-sensitive adhesive composition of the present invention has excellent antistatic properties and excellent balance of adhesive force at low and high- , Durability performance and reworkability (no contamination of the adherend after the surface protective film is overlaid with the ballpoint pen through the pressure-sensitive adhesive layer) is also excellent. Therefore, it can be preferably used as a surface protective film of a polarizing plate.

The thickness of the pressure-sensitive adhesive layer (2) used in the antistatic surface protective film (10) according to the present invention is not particularly limited. For example, the thickness is preferably about 5 to 40 m, Is more preferable. When the antistatic surface protective film is peeled off from the adherend, the peeling strength (adhesive force) of the antistatic surface protective film to the adherend surface is in the range of 0.03 to 0.3 N / 25 mm, In view of its excellent operability. It is also preferable that the peeling force of the release film 5 from the pressure-sensitive adhesive layer 2 is 0.2 N / 50 mm or less because of the excellent operability in peeling the release film 5 from the antistatic surface protective film 10 desirable.

The release film 5 used in the antistatic surface protective film 10 according to the present invention is formed by applying a releasing agent containing dimethylpolysiloxane as a main component and a silicone compound as a liquid at 20 캜 to one side of the resin film 3 A release agent layer 4 using a resin composition containing an antistatic agent is formed.

As the resin film (3), a polyester film, a polyamide film, a polyethylene film, a polypropylene film, a polyimide film and the like can be given, but a polyester film is particularly preferable because of its excellent transparency and relatively low cost Do. The resin film may be a non-oriented film or a uniaxially or biaxially oriented film. Further, the stretching magnification of the stretched film or the orientation angle of the axial method formed by crystallization of the stretched film may be controlled to a specific value.

The thickness of the resin film 3 is not particularly limited. For example, the thickness of the resin film 3 is preferably about 12 to 100 mu m, and more preferably about 20 to 50 mu m.

If necessary, the surface of the resin film 3 may be subjected to this adhesion treatment such as surface modification by corona discharge, application of an anchor coat, or the like.

The releasing agent comprising dimethylpolysiloxane as a main component constituting the releasing agent layer (4) includes known releasing agents such as addition reaction type, condensation reaction type, cationic polymerization type and radical polymerization type. KS-777, KS-777, KS-777, KS-830 (manufactured by Shin-Etsu Chemical Co., Ltd.), and SRX- LTC-350G, LTC-310 (manufactured by Toray Dow Corning Co., Ltd.), and the like. Commercially available products of the condensation reaction type include, for example, SRX-290 and SYLOFF-23 (manufactured by Toray Dow Corning Co., Ltd.). Examples of commercially available products of the cationic polymerization type include TPR-6501, TPR-6500, UV9300, VU9315, UV9430 (manufactured by Momentive Performance Materials Ltd.), X62-7622 (manufactured by Shinetsu Kagaku Kogyo Co., Ltd.) And the like. Commercially available products as the radical polymerization type include, for example, X62-7205 (manufactured by Shin-Etsu Chemical Co., Ltd.).

Examples of the silicon-based compound which is liquid at 20 占 폚 constituting the release agent layer 4 include polyether-modified silicone, alkyl-modified silicone, carbinol higher fatty acid ester-modified silicone and the like. In the present invention, in order to improve the antistatic property of the surface of the pressure-sensitive adhesive layer, a silicone compound which is a liquid at 20 占 폚 in a state of being used in a release agent layer containing dimethylpolysiloxane as a main component is used. Of the modified silicone compounds, polyether-modified silicone is preferred for use in the present invention. The polyether chain in the polyether-modified silicone is composed of ethylene oxide, propylene oxide, and the like. For example, by selecting the molecular weight of the polyethylene oxide used in the side chain, properties such as compatibility with the silicone release agent and antistatic effect Is adjusted.

KF-352A, KF-353A, KF-355A, KF-642 (manufactured by Shin-Etsu Chemical Co., Ltd.), and KF- (Manufactured by Momentive Performance Materials Co., Ltd.), BYK-300, BYK (manufactured by Mitsubishi Corporation), SH8400, SH8700, SF8410 (manufactured by Toray Dow Corning Co., Ltd.), TSF-4440, TSF-4441, TSF- -306, BYK-307, BYK-320, BYK-325, and BYK-330 (manufactured by Big Chemical).

The amount of the silicon compound added as a liquid at 20 占 폚 to the releasing agent containing dimethylpolysiloxane as a main component differs depending on the kind of the silicone compound and the degree of compatibility with the exfoliating agent. However, when the antistatic surface protective film is peeled off from the adherend, A stain resistance to an adherend, a sticking property, and the like.

As the antistatic agent constituting the release agent layer 4, it is preferable that the antistatic agent is good in dispersibility with respect to a remover solution containing dimethylpolysiloxane as a main component and does not inhibit the hardening of the remover containing dimethylpolysiloxane as a main component. As such an antistatic agent, an alkali metal salt is preferable.

Examples of the alkali metal salt include a metal salt composed of lithium, sodium and potassium. Specific examples of the alkali metal salt include a cation composed of Li ⁺ , Na ⁺ , K ⁺ and a cation selected from the group consisting of Cl ^- , Br ^- , I ^- , BF _{4 ^{-, PF 6 -, SCN -}} , ClO 4 -, CF 3 SO 3 -, (CF 3 SO 2) 2 N -, (C 2 F 5 SO 2) 2 N -, (CF 3 SO 2) 3 C - Is preferably used as the metal salt. Among _{others, LiBr, LiI, LiBF 4,} LiPF 6, LiSCN, LiClO 4, LiCF 3 SO 3, Li (CF 3 SO 2) 2 N, Li (C 2 F 5 SO 2) 2 N, Li (CF 3 SO ₂ ) ₃ C and the like are preferably used. These alkali metal salts may be used alone or in combination of two or more. To stabilize the ionic material, a compound containing a polyoxyalkylene structure may be added.

The amount of the antistatic agent to be added to the releasing agent containing dimethylpolysiloxane as a main component differs depending on the kind of the antistatic agent and the degree of affinity with the exfoliating agent. However, when the antistatic surface protective film is peeled from the adherend, The stain resistance to the complex, and the adhesive property.

The method of mixing the releasing agent containing dimethylpolysiloxane as a main component and the polyether-modified silicone and the antistatic agent is not particularly limited. A method of adding and mixing a polyether-modified silicone and an antistatic agent to a releasing agent containing dimethylpolysiloxane as a main component and then adding and mixing a catalyst for releasing agent curing, a method of diluting a releasing agent containing dimethylpolysiloxane as a main component in advance with an organic solvent, A method of adding and mixing silicone and an antistatic agent and a releasing agent curing catalyst, a method of previously adding a silane-based releasing agent to an organic solvent, adding and mixing a catalyst, and then adding and mixing a polyether- Or the like. If necessary, a material for assisting an antistatic effect, such as a adhesion improver such as a silane coupling agent or a compound containing a polyoxyalkylene group, may be added.

The mixing ratio of the releasing agent containing dimethylpolysiloxane as a main component and the polyether-modified silicone and the antistatic agent is not particularly limited, but it is preferable that the amount of the polyether-modified silicone and the antistatic agent is 5 To 100 parts by weight is preferable. When the addition amount of the polyether-modified silicone and the antistatic agent in terms of solid content is less than 5 parts by weight based on 100 parts by weight of the solid content of the releasing agent comprising dimethylpolysiloxane as a main component, the amount of the antistatic agent transferred onto the surface of the pressure- It becomes difficult to exert the function of When the addition amount of the polyether-modified silicone and the antistatic agent in terms of solid content is more than 100 parts by weight based on 100 parts by weight of the solid content of the releasing agent containing dimethylpolysiloxane as a main component, dimethylpolysiloxane as a main component Is also transferred to the surface of the pressure-sensitive adhesive layer, there is a possibility that the pressure-sensitive adhesive property of the pressure-sensitive adhesive is lowered.

The method of forming the pressure-sensitive adhesive layer (2) and the method of bonding the release film (5) to the base film (1) of the antistatic surface protective film (10) according to the present invention may be carried out by a known method, Do not. Specifically, there are (1) a method of applying a resin composition for forming a pressure-sensitive adhesive layer 2 on one side of a base film 1 and drying to form a pressure-sensitive adhesive layer, followed by bonding the release film 5 2) a method of applying a resin composition for forming the pressure-sensitive adhesive layer 2 on the surface of the release film 5 followed by drying to form a pressure-sensitive adhesive layer, followed by bonding the base film 1, May be used.

The pressure-sensitive adhesive layer (2) may be formed on the surface of the base film (1) by a known method. Specifically, known coating methods such as reverse coating, comma coating, gravure coating, slot die coating, Meyer bar coating and air knife coating can be used.

In the same manner, the release agent layer 4 may be formed on the resin film 3 by a known method. Specifically, known coating methods such as gravure coating, Meyer bar coating and air knife coating can be used.

2 is a cross-sectional view showing a state in which a release film is peeled from an antistatic surface protective film of the present invention.

The silicone-based compound and the antistatic agent (which are included in the release agent layer 4 of the release film 5) and which are liquid at 20 占 폚 7) is transferred (adhered) to the surface of the pressure-sensitive adhesive layer 2 of the antistatic surface protective film 10. Therefore, in FIG. 2, the silicone compound and the antistatic agent which are liquid at 20 ° C and transferred onto the surface of the pressure-sensitive adhesive layer (2) of the antistatic surface protective film are schematically shown by the reference numeral 7.

In the antistatic surface protective film according to the present invention, when the antistatic surface protective film 11 in the peeled state of the release film shown in Fig. 2 is adhered to an adherend, 20 The silicone compound and the antistatic agent which are liquids come into contact with the surface of the adherend. Thereby, the peeling electrification voltage when the antistatic surface protective film is peeled from the adherend can be suppressed again.

3 is a cross-sectional view showing an embodiment of the optical component of the present invention.

The peeling film 5 is peeled off from the antistatic surface protective film 10 of the present invention and the optical component 8 as the adherend is peeled off from the antistatic surface protective film 10 with the pressure sensitive adhesive layer 2 exposed thereon Lt; / RTI >

3 shows an optical component 20 to which the antistatic surface protective film 10 of the present invention is bonded. Examples of the optical component include optical films such as a polarizing plate, a retardation plate, a lens film, a polarizing plate serving as a retardation plate, and a polarizing plate serving also as a lens film. Such an optical component is used as a constituent member of a liquid crystal display device such as a liquid crystal display panel and an optical system device of various instruments. Examples of the optical component include optical films such as an antireflection film, a hard coat film, and a transparent conductive film for a touch panel. Particularly, the optical film is adhered to an antifouling treated surface of an optical film such as a low reflection polarizing plate (LR polarizing plate) or an anti-glare low reflection polarizing plate (AG-LR polarizing plate) whose surface has been subjected to antifouling treatment with a silicon compound or a fluorine compound , And an antistatic surface protective film.

According to the optical component of the present invention, since the peeling electrification voltage can be suppressed sufficiently low when the antistatic surface protective film 10 is peeled off from the optical component (optical film) as the adherend, the driver IC, the TFT element, There is no risk of destroying circuit components such as a line driving circuit and the like, the production efficiency in the process of manufacturing a liquid crystal display panel or the like can be enhanced and the reliability of the production process can be maintained.

Example

EXAMPLES Next, the present invention will be described in detail by examples.

≪ Preparation of pressure-sensitive adhesive composition >

[Example 1]

Nitrogen gas was introduced into a reactor equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and the air in the reactor was replaced with nitrogen gas. Then, 100 parts by weight of 2-ethylhexyl acrylate, 5.0 parts by weight of 8-hydroxyoctyl acrylate and 60 parts by weight of a solvent (ethyl acetate) were added to the reactor. Thereafter, 0.1 part by weight of azobisisobutyronitrile as a polymerization initiator was added dropwise over 2 hours and reacted at 65 DEG C for 6 hours to obtain an acrylic copolymer solution of Example 1 having a weight average molecular weight of 500,000. To this acrylic copolymer solution, 8.5 parts by weight of acetylacetone was added and stirred. Then, 2.0 parts by weight of Coronate HX (isocyanurate of hexamethylene diisocyanate compound) and 0.1 part by weight of titanium trisacetylacetonate were added And the mixture was stirred and mixed to obtain the pressure-sensitive adhesive composition of Example 1.

[Examples 2 to 6 and Comparative Examples 1 to 3]

The pressure-sensitive adhesive compositions of Examples 2 to 6 and Comparative Examples 1 to 3 were obtained in the same manner as in Example 1 except that the composition of the pressure-sensitive adhesive composition of Example 1 was changed as shown in Table 1 and Table 2, respectively. The monomers (A), (B), (C), (G) and "carboxyl group-containing monomers" contained in the acrylic copolymer in Tables 1 and 2 are.

Table 1 and Table 2 are obtained by dividing the whole table showing the compounding ratio of each component into two, and the numerical values of the parts by weight obtained by taking the total of the group (A) as 100 parts by weight are shown in parentheses. Tables 3 and 4 show the compound names of the weak symbols of the respective components used in Tables 1 and 2. Coronate (registered trademark) HX, HL and L are trade names of Nippon Polyurethane Industry Co., Ltd., and Takenate (registered trademark) D-140N, D-127N and D-110N are trade names of Mitsui Chemicals,

<Synthesis of bifunctional isocyanate compound>

The bifunctional isocyanate compounds of Synthesis Examples 1 and 2 were synthesized in the following manner. As shown in Tables 5 and 6, the diisocyanate and the diol compound were mixed at a molar ratio of NCO / OH = 16, and the mixture was reacted at 120 ° C for 3 hours. Thereafter, a thin film evaporator was used to conduct unreacted Of diisocyanate was removed to obtain a desired bifunctional isocyanate compound.

<Preparation of antistatic surface protective film>

[Example 1]

, 5 parts by weight of an addition reaction type silicone (trade name: SRX-345, manufactured by Toray Dow Corning Co., Ltd.), 0.15 part by weight of polyether-modified silicone (SH8400, trade name; manufactured by Toray Dow Corning Co., , 95 parts by weight of a mixed solvent of toluene and ethyl acetate in a ratio of 1: 1, and 0.05 parts by weight of a platinum catalyst (trade name: SRX-212 Catalyst manufactured by Toray Dow Corning Co., Ltd.) The paint forming the release agent layer of Example 1 was adjusted. A coating material for forming the release agent layer of Example 1 was applied to the surface of a polyethylene terephthalate film having a thickness of 38 占 퐉 so that the thickness after drying would be 0.2 占 퐉 and dried in a hot air circulating oven at 120 占 폚 for one minute, A release film of Example 1 was obtained.

The pressure-sensitive adhesive composition of Example 1 was coated on the surface of a 38 占 퐉 -thick polyethylene terephthalate film so that the thickness after drying became 20 占 퐉 and dried in a hot air circulating oven at 100 占 폚 for 2 minutes to form a pressure-sensitive adhesive layer. Thereafter, the release agent layer (silicone-treated surface) of the release film of Example 1 prepared above was bonded to the surface of the pressure-sensitive adhesive layer. The obtained pressure-sensitive adhesive film was kept at 40 캜 for 5 days, and the pressure-sensitive adhesive was cured to obtain an antistatic surface protective film of Example 1.

[Examples 2 to 6]

An antistatic surface protective film of each of Examples 2 to 6 was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive composition of Example 1 was changed to the pressure-sensitive adhesive composition of each of Examples 2 to 6.

[Comparative Example 1]

5 parts by weight of an addition reaction type silicone (trade name: SRX-345, manufactured by Toray Dow Corning Co., Ltd.), 95 parts by weight of a 1: 1 mixed solvent of toluene and ethyl acetate and 100 parts by weight of a platinum catalyst (manufactured by Toray Dow Corning Co., Ltd., product name: SRX-212 Catalyst) were mixed and stirred and mixed to prepare a coating material for forming the release agent layer of Comparative Example 1. A coating material for forming the release agent layer of Comparative Example 1 was applied to the surface of a polyethylene terephthalate film having a thickness of 38 占 퐉 so that the thickness after drying would be 0.2 占 퐉 and dried in a hot air circulating oven at 120 占 폚 for one minute, A release film of Comparative Example 1 was obtained.

The pressure-sensitive adhesive composition of Comparative Example 1 was coated on the surface of a 38 占 퐉 -thick polyethylene terephthalate film so that the thickness after drying was 20 占 퐉 and dried in a hot air circulating oven at 100 占 폚 for 2 minutes to form a pressure-sensitive adhesive layer. Thereafter, a release agent layer (silicone-treated surface) of the release film of Comparative Example 1 prepared above was bonded to the surface of the pressure-sensitive adhesive layer. The obtained pressure-sensitive adhesive film was kept at an environment of 40 캜 for 5 days, and the pressure-sensitive adhesive was cured to obtain an antistatic surface protective film of Comparative Example 1.

[Comparative Example 2]

An antistatic surface protective film of Comparative Example 2 was obtained in the same manner as in Comparative Example 1 except that the pressure-sensitive adhesive composition of Comparative Example 1 was changed to the pressure-sensitive adhesive composition of Comparative Example 2.

[Comparative Example 3]

An antistatic surface protective film of Comparative Example 3 was obtained in the same manner as in Example 1 except that the pressure-sensitive adhesive composition of Example 1 was replaced by the pressure-sensitive adhesive composition of Comparative Example 3.

Table 7 shows the compositions and thicknesses of the release agent layers in the antistatic surface protective films of Examples 1 to 6 and Comparative Examples 1 to 3.

<Test Method and Evaluation>

The surface protective films of Examples 1 to 6 and Comparative Examples 1 to 3 were aged for 7 days under an atmosphere of 23 ° C and 50% RH, and then a release film (PET resin coated with silicone resin) was peeled off to form a pressure- The thus-exposed sample was used as a sample for measuring the surface resistivity.

The surface protective film on which the pressure-sensitive adhesive layer was exposed was applied to the surface of the polarizing plate attached to the liquid crystal cell via the pressure-sensitive adhesive layer, allowed to stand for one day, autoclaved at 50 DEG C and 5 atm for 20 minutes, The sample was allowed to stand for 12 hours to measure adhesion, peeling electrification, and reworkability.

<Adhesion>

The test specimen obtained by mixing the above-obtained measurement specimen (the surface protective film having a width of 25 mm with the surface of the polarizing plate) was subjected to a low speed peeling speed (0.3 m / min) and a high speed peeling speed (30 m / min) , And the peel strength measured was regarded as adhesive force.

<Surface resistivity>

After aging, a releasing film (PET resin film coated with a silicone resin) was peeled off to form a pressure-sensitive adhesive layer before being adhered to the polarizing plate, and the pressure-sensitive adhesive layer was exposed using a resistivity meter Hiresta UP-HT450 (manufactured by Mitsubishi Chemical Corporation) The surface resistivity was measured.

<Peeling Voltage>

The voltage (high voltage) generated when the polarizing plate was charged by 180 ° peeling at a tensile speed of 30 m / min was measured using a high-precision electrostatic sensor SK-035, SK-200 (manufactured by Keyes Corporation) , And the maximum value of the measured value was taken as the peeling electrification voltage.

<Workability>

The surface protective film of the measurement sample thus obtained was overlaid with a ballpoint pen (load: 500 g, three round trips), and the surface protective film was peeled off from the polarizing plate to observe the surface of the polarizing plate. The evaluation target criterion was "◯" when no pollution was observed on the polarizer, "Δ" when the pollution was confirmed to be at least partially along the locus covered with the ballpoint pen, and the contamination was confirmed along the locus of the ballpoint pen. Quot ;, and the case where the release of the pressure-sensitive adhesive was confirmed also from &quot; X &quot;.

Table 8 shows the evaluation results. In addition, the surface resistivity is expressed by a method ("m" is an arbitrary real number value and "n" is a positive integer) in which "m × 10 ^{+ n} " is "mE + n".

From the measurement results shown in Table 8, the following can be found.

The antistatic surface protective film of Examples 1 to 6 according to the present invention had an appropriate adhesive force and was free from contamination to the surface of the adherend and had a peeling electrification voltage when the antistatic surface protective film was peeled from the adherend low.

On the other hand, the antistatic surface protective film of Comparative Example 1 in which a silicone compound and an antistatic agent were added to the pressure-sensitive adhesive layer had a low surface resistivity of the pressure-sensitive adhesive layer and a good adhesive strength, resulting in high peeling electrification voltage and poor reworkability . Further, in Comparative Example 2, the pressure-sensitive adhesive was gelled and could not be applied because of a large amount of the crosslinking accelerator added. In Comparative Example 3, since a monomer containing a carboxyl group was contained, the adhesive force was large, It was a little apart.

That is, in Comparative Examples 1 and 2 in which a silicone compound and an antistatic agent were mixed in a pressure-sensitive adhesive, it was difficult to achieve both reduction in peeling electrification voltage and staining property to an adherend. On the other hand, in Examples 1 to 6, in which a silicone compound and an antistatic agent were added to a release agent layer and a silicone compound and an antistatic agent were transferred to the surface of the pressure-sensitive adhesive layer, there was an effect of reducing the peeling electrification by a small addition amount. And a good anti-static surface protective film was obtained.

The antistatic surface protective film of the present invention can be used for protecting the surface of an optical component or the like in a production process such as a polarizing plate, a retardation film, a lens film for display, an optical film, Can be used for. Particularly, when the antireflection film is used as an antistatic surface protective film for an optical film such as an LR polarizing plate or an AG-LR polarizing plate whose surface has been subjected to antifouling treatment with a silicone compound, a fluorine compound or the like, the amount of static electricity can do.

The antistatic surface protective film of the present invention is excellent in industrial utility value because it has less stain on the adherend, does not deteriorate with time, and has excellent peeling electrification preventing performance, thereby improving the yield of the production process.

One… Base film, 2 ... Adhesive layer, 3 ... Resin film, 4 ... The release agent layer, 5 ... Peeling film, 7 ... Silicone compounds and antistatic agents which are liquid at 20 占 폚, 8 ... Adhesive (optical parts), 10 ... Antistatic surface protection film, 11 ... Antistatic surface protection film with exfoliating film, 20 ... Antistatic surface protective film.

Claims (6)

An antistatic surface protective film for an antistatic surface protective film, which is capable of transferring an antistatic agent onto the surface of the pressure sensitive adhesive layer of an antistatic surface protective film having a pressure sensitive adhesive layer formed on one side of a base film made of a resin having transparency,
The release film for antistatic surface protective film is formed by laminating a release agent layer containing an antistatic agent on one side of a resin film, wherein the release agent layer comprises a release agent comprising dimethylpolysiloxane as a main component and a silicone compound A polyether-modified silicone, and a resin composition containing an alkali metal salt as the antistatic agent,
The pressure-sensitive adhesive layer is formed by crosslinking an acrylic polymer, a cross-linking agent, a cross-linking accelerator, and a pressure-sensitive adhesive composition containing a keto-enol triblock compound,
Wherein the acrylic polymer is at least one monomer selected from the group consisting of (A) a monomer copolymerizable with at least one (meth) acrylic acid ester monomer having an alkyl group having from 4 to 18 carbon atoms, (B) a copolymerizable monomer containing a hydroxyl group, and (C) (Meth) acrylate monomer containing no nitrogen-containing vinyl monomer or an alkoxy group-containing alkyl (meth) acrylate monomer without containing a carboxyl group-containing copolymerizable monomer,
The crosslinking accelerator is at least one selected from the group consisting of an aluminum chelate compound, a titanium chelate compound and an iron chelate compound,
The pressure-sensitive adhesive layer contains no antistatic agent inside,
Wherein the release agent layer contains the polyether-modified silicone and the alkali metal salt in a proportion of 5 to 100 parts by weight, as solid matter, based on 100 parts by weight of the solid content of the releasing agent comprising dimethylpolysiloxane as a main component,
When the release film for antistatic surface protective film is bonded to the surface of the pressure-sensitive adhesive layer via the release agent layer, the polyether-modified silicone contained in the release agent layer and the alkali metal salt are transferred onto the surface of the pressure- Wherein said antistatic surface protective film has a thickness of at least 100 nm. The method according to claim 1,
(G) a polyalkylene glycol mono (meth) acrylic acid ester monomer as the copolymerizable monomer group. 3. The method according to claim 1 or 2,
(Meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (Meth) acrylate, at least one antistatic surface selected from the group consisting of N-hydroxy (meth) acrylamide, N-hydroxymethyl (meth) acrylamide and N-hydroxyethyl Peeling film for protective film. delete An antistatic surface protective film formed by bonding a release film for an antistatic surface protective film according to claim 1 or 2. An optical component in which the antistatic surface protective film of claim 5 is bonded.

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