TW201610053A - Adhesive composition and surface-protective film - Google Patents

Abstract

The present invention provides an adhesive composition and a surface-protective film that have excellent antistatic performance, that have excellent adhesive strength balance at a slow peel rate and at a fast peel rate, and that further also have a long pot life, and excellent durability and reworkability. The present invention relates to an adhesive composition that contains, with respect to 100 parts by weight of an acrylic-based polymer, 50 to 95 parts by weight of a (meth) acrylic acid ester monomer having a C4 to C18 alkyl group, 0.1 to 10 parts by weight of a hydroxyl group-containing monomer, 0.1 to 1.0 parts by weight of a carboxyl group-containing monomer, 8 to 50 parts by weight of a polyalkylene glycol mono (meth) acrylic acid ester monomer, and 0.1 to 20 parts by weight of a nitrogen-containing vinyl monomer not containing a hydroxyl group or an alkoxy group-containing alkyl (meth) acrylate monomer, wherein the adhesive composition does not contain a siloxane compound and contains a bifunctional or higher isocyanate compound, a cross-linking catalyst, a keto-enol tautomer compound, and an antistatic agent.

Description

Adhesive composition and surface protection film

The present invention relates to a surface protective film for use in a manufacturing step of a liquid crystal display. More specifically, the adhesive composition for a surface protective film used to protect the surface of an optical element such as a polarizing plate or a retardation film by bonding to a surface of an optical element such as a polarizing plate or a retardation film constituting a liquid crystal display And a surface protective film obtained by using the adhesive composition.

In the manufacturing process of an optical element such as a polarizing plate or a phase difference plate which constitutes an element of a liquid crystal display, a surface protective film for temporarily protecting the surface of the optical element is bonded. Such a surface protective film is used only in the step of manufacturing an optical element, and is peeled off from the optical element when the optical element is assembled to the liquid crystal display. Since such a surface protective film for protecting the surface of an optical element is used only in a manufacturing step, it is also generally called an engineered film.

In the surface protective film used in the step of producing an optical element, a layer of a binder is formed on one side of a polyethylene terephthalate (PET) resin film having optical transparency, and is bonded. A release film for performing the release treatment for protecting the adhesive layer is attached to the adhesive layer before the optical element.

In addition, optical elements such as a polarizing plate and a phase difference plate are bonded to the surface protective film. In the state, since the product inspection is performed with optical evaluation such as the display capability, color tone, contrast, and foreign matter incorporation of the liquid crystal display panel, it is required that bubbles and foreign matter are not adhered to the adhesive layer as a required performance for the surface protective film.

In addition, in recent years, when the surface protective film is peeled off from an optical element such as a polarizing plate or a phase difference plate, there is a concern that the peeling electrification caused by static electricity generated when the adherend is peeled off from the adhesive layer is electrically controlled to the liquid crystal display. The failure of the circuit has an effect and requires excellent antistatic properties for the adhesive layer.

When the surface protective film is bonded to an optical element such as a polarizing plate or a retardation plate, the surface protective film is adhered again once the surface protective film is peeled off for various reasons. In this case, it is required to be easily peeled off from the optical member of the adherend ( Reworkability).

Further, when the surface protective film is peeled off from an optical element such as a polarizing plate or a phase difference plate, it is required to be quickly peeled off. As described above, even if it can be peeled off quickly even by high-speed peeling, it is required that the adhesive force changes little due to a change in the peeling speed.

Thus, in recent years, as a required performance for the adhesive layer constituting the surface protective film, from the viewpoint of ease of use in the use of the surface protective film, it is required to (1) maintain adhesion at a low peeling speed and a high peeling speed. Balance of force, (2) prevention of paste residue, (3) excellent antistatic performance and (4) reworkability.

However, even if the respective required properties in the above (1) to (4) satisfying the required properties of the adhesive layer constituting the surface protective film are satisfied, it is required to simultaneously satisfy the required adhesive layer of the surface protective film (1)~( 4) All required performance is a very difficult subject.

For example, for (1) maintaining a balance of adhesive force at a low peeling speed and a high peeling speed, and (2) preventing the occurrence of paste residue, it is known as follows proposal.

An acrylic acid obtained by crosslinking a copolymer of a (meth)acrylic acid alkyl ester having an alkyl group having 7 or less carbon atoms and a carboxyl group-containing copolymerizable compound as a main component and crosslinking the mixture with a crosslinking agent. In the adhesive layer, there is a problem that the adhesive is transferred to the adherend side when the adhesive is applied for a long period of time, and the adhesion with respect to the adherend is increased with time. In order to avoid this, it is known to use a copolymer of an alkyl (meth)acrylate having an alkyl group having 8 to 10 carbon atoms and a copolymerizable compound having an alcoholic hydroxyl group, which is carried out by using a crosslinking agent. A binder layer obtained by crosslinking treatment (Patent Document 1).

Further, a copolymer layer obtained by blending a copolymer of a (meth)acrylic acid alkyl ester and a carboxyl group-containing copolymerizable compound in a copolymer having the same amount as described above and crosslinking it with a crosslinking agent has been proposed. Wait. However, when these surfaces are protected by a plastic plate having a low surface tension and a smooth surface, there are problems such as peeling due to floating during processing and storage, and/or peeling at a high speed in a manually operated region. The problem of poor removability at the time.

In order to solve these problems, a binder composition is proposed, which comprises an alkyl (meth)acrylate 100 having a (meth)acrylic acid alkyl ester having a carbon number of 8 to 10 as a main component. To the parts by weight, b) a copolymer of a monomer mixture of 1 to 15 parts by weight of a carboxyl group-containing copolymerizable compound and c) 3 to 100 parts by weight of a vinyl ester of an aliphatic carboxylic acid having 1 to 5 carbon atoms; In the copolymer of the monomer mixture, a crosslinking agent having an equivalent weight or more with respect to the carboxyl group of the component b) is blended (Patent Document 2).

In the adhesive composition described in Patent Document 2, peeling phenomenon such as floating does not occur during processing or storage, and the adhesion force increases with time. It is excellent in re-peelability and can be peeled off with a small force even when stored for a long period of time in a high-temperature atmosphere. In this case, no residue remains on the adherend, and even if high-speed peeling is performed, it can be used. Small force is peeled off again.

Further, (3) Excellent antistatic performance As a method for imparting antistatic properties to a surface protective film, a method of mixing an antistatic agent into a base film or the like is disclosed. As the antistatic agent, for example, (a) various cationic antistatic agents having a cationic group such as a quaternary ammonium salt, a pyridinium salt, a primary amino group to a tertiary amino group, and (b) a sulfonate group or a sulfate salt are disclosed. An anionic antistatic agent such as an anionic group such as a phosphatide group or a phosphonate group; (a) an amphoteric antistatic agent such as an amino acid system or an aminosulfate group; (d) an amino alcohol system or a glycerin system And a non-ionic antistatic agent such as a polyethylene glycol system, and (e) a polymer type antistatic agent obtained by polymerizing the antistatic agent as described above (Patent Document 3).

Further, in recent years, it has been proposed to contain such an antistatic agent in a base film or to apply such an antistatic agent directly to the adhesive layer without applying it to the surface of the base film.

Further, (4) Reworkability, for example, in an acrylic resin, a curing agent for an isocyanate compound and a specific phthalate oligomer are blended in an amount of 0.0001 to 10 parts by weight based on 100 parts by weight of the acrylic resin. The obtained binder composition (Patent Document 4).

In Patent Document 4, an alkyl acrylate having an alkyl group having a carbon number of 2 to 12 or an alkyl methacrylate having an alkyl group having a carbon number of 4 to 12 is used as a main monomer component, for example. A monomer component containing another functional group such as a carboxyl group-containing monomer may be contained. In general, it is preferable to contain 50% by weight or more of the above-mentioned main monomer, and the content of the monomer component containing a functional group is 0.001 to 50 weight. The amount % is preferably 0.001 to 25% by weight, and more preferably 0.01 to 25% by weight. The adhesive composition described in Patent Document 4 has a small change in cohesive force and adhesive force over time at high temperature or high temperature and high humidity, and exhibits an excellent effect on adhesion to a curved surface, so that it has rework. Sex.

In general, when the adhesive layer is a flexible adhesive layer, the paste residue is likely to occur, and the reworkability is liable to lower. That is, it is difficult to peel off at the time of erroneous bonding, and it is easy to make it difficult to re-attach. Therefore, it is considered that it is necessary to crosslink the monomer having a functional group such as a carboxyl group with the main component to make the adhesive layer have a certain hardness in order to have reworkability.

[Previous Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Laid-Open Publication No. SHO 63-225677

Patent Document 2: Japanese Patent Laid-Open No. Hei 11-256111

Patent Document 3: Japanese Patent Laid-Open No. Hei 11-070629

Patent Document 4: Japanese Patent Laid-Open No. Hei 8-199130

In the prior art, as a required performance for the adhesive layer constituting the surface protective film, the balance of the adhesive force is maintained at a low peeling speed and a high peeling speed, and excellent antistatic properties and reworkability are required, but even It can meet the respective required performance, and can not meet all the required performance required for the adhesive layer of the surface protective film.

The present invention has been made in view of the above circumstances to provide a device Excellent antistatic performance, excellent balance of adhesion at low peeling speed and high peeling speed, and a binder composition and a surface protective film which are excellent in pot life, durability, and reworkability are problems.

In order to solve the above problems, the present invention provides a binder composition comprising an acrylic polymer composed of a copolymer of a copolymerizable monomer, wherein the copolymerizable monomer contains 50 to 95 parts by weight based on 100 parts by weight of the acrylic polymer. The (A) alkyl group has a C4 to C18 (meth) acrylate monomer, and 0.1 to 10 parts by weight of the copolymerizable monomer group (B) a hydroxyl group-containing copolymerizable single unit 0.1 to 1.0 part by weight of (C) carboxyl group-containing copolymerizable monomer, 8 to 50 parts by weight of (D) polyalkylene glycol mono(meth)acrylate monomer, 0.1 to 20 parts by weight (E) at least one of a nitrogen-containing vinyl monomer having no hydroxyl group or an alkoxy group-containing alkyl (meth) acrylate monomer, the above binder composition further containing no oxoxane compound, and containing (F) a difunctional or higher isocyanate compound, (G) a crosslinking catalyst, (H) a keto-enol tautomer compound, (I) an ionic compound having an melting point of 25 to 50 ° C as an antistatic agent and/or Or an ionic compound containing an acryloyl group.

It is preferable to contain 0.1 to 10 parts by weight of the above (F) difunctional or higher isocyanate compound, and 0.001 to 0.5 part by weight of the above (G) crosslinking catalyst, and 0.1 to 300 parts by weight, based on 100 parts by weight of the acrylic polymer. The above (H) keto-enol tautomer compound, and the above (I) antistatic agent contains an ionic compound having a melting point of 25 to 50 ° C in the above binder composition and copolymerization in the above copolymer The total amount of the ionic compound containing an acrylonitrile group is 0.01 to 5.0 parts by weight, and the above (D) polyalkylene glycol mono(A) Composition of the acrylate monomer The average number of repetitions of the alkylene oxide of the polyalkylene glycol chain is 3 to 14, the diester portion of the monomer is 0.3% or less, and the water content is 0.1% or less and in the water. The solubility is a turbidity value of 2% or less in a 20% aqueous solution state.

Preferably, the (G) crosslinking catalyst is a crosslinking catalyst of a metal chelate compound, and the weight ratio of the crosslinking catalyst of the (G) metal chelate compound to the (H) keto-enol tautomer compound (H) ) / (G) is 70~1000.

Preferably, the (B) hydroxyl group-containing copolymerizable monomer is selected from the group consisting of 8-hydroxyoctyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, At least one of 2-hydroxyethyl methyl acrylate, N-hydroxy (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, and N-hydroxyethyl (meth) acrylamide the above.

Preferably, the (C) carboxyl group-containing copolymerizable monomer is selected from the group consisting of (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, and 2-(meth)acryloxyloxy group. Ethyl hexahydrophthalic acid, 2-(methyl)propenyloxypropyl hexahydrophthalic acid, 2-(meth) propylene methoxyethyl phthalate, 2-(methyl ) acryloxyethyl succinic acid, 2-(methyl) propylene oxiranyl ethyl maleic acid, carboxy polycaprolactone mono (meth) acrylate, 2-(methyl) propylene methoxy ethoxylate At least one of the group of tetrahydrophthalic acid.

Preferably, the (D) polyalkylene glycol mono(meth)acrylate monomer is selected from the group consisting of polyalkylene glycol mono(meth)acrylates, methoxypolyalkylene glycols (methyl) At least one of acrylate and ethoxypolyalkylene glycol (meth) acrylate.

Preferably, the binder composition has a gel fraction of 95 to 100% after crosslinking.

In the above-mentioned (F) difunctional or higher isocyanate compound, the difunctional isocyanate compound is an acyclic aliphatic isocyanate compound, which is a compound obtained by reacting a diisocyanate compound with a diol compound, and is a diisocyanate compound and is a fat. a diisocyanate selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, trimethyl hexamethylene diisocyanate, and lysine diisocyanate as a diol a compound comprising a group selected from the group consisting of 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-ethyl -2-butyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2-dimethyl-1,3-propanediol monohydroxy pivalate, polyethylene glycol, One of polypropylene glycols, as a trifunctional isocyanate compound, including an isocyanurate body of a hexamethylene diisocyanate compound, an isocyanurate body of an isophorone diisocyanate compound, a hexamethylene diisocyanate compound Adduct, addition of isophorone diisocyanate compound Compound, biuret body of hexamethylene diisocyanate compound, biuret body of isophorone diisocyanate compound, isocyanurate body of toluene diisocyanate compound, benzene dimethylene diisocyanate compound Isocyanurate body, isocyanurate body of hydrogenated benzene dimethylene diisocyanate compound, adduct of tolylene diisocyanate compound, adduct of benzene dimethylene diisocyanate compound, hydrogenated benzodiazepine An adduct of a methyl diisocyanate compound.

It is preferable that the adhesive layer obtained by crosslinking the above-mentioned binder composition has an adhesive force at a low peeling speed of 0.3 m/min of 0.04 to 0.2 N/25 mm, and an adhesive force at a high peeling speed of 30 m/min. 2.0N/25mm or less.

The surface resistivity of the adhesive layer obtained by crosslinking the above-mentioned binder composition is preferably 9.0×10 ⁺¹¹ Ω/□ or less, and the peeling tape voltage is ±0 to 0.5 kV.

Further, the present invention provides a pressure-sensitive adhesive film obtained by forming a pressure-sensitive adhesive layer obtained by crosslinking the pressure-sensitive adhesive composition on one surface or both surfaces of a resin film.

Further, the present invention provides a surface protective film obtained by forming a binder layer obtained by crosslinking the above-mentioned binder composition on one surface of a resin film, and scraping with a ballpoint pen through the above-mentioned binder layer After the surface protection film is applied, the stain does not transfer to the adherend.

The above surface protective film can be used as a surface protective film for a polarizing plate.

It is preferable to carry out an antistatic treatment and an antifouling treatment on the side opposite to the side of the resin film on which the above-mentioned binder layer is formed.

According to the present invention, it is possible to satisfy all the properties required for the adhesive layer of the surface protective film which cannot be solved by the conventional technique, and it is possible to obtain excellent antistatic properties and excellent performance for preventing the occurrence of paste residue. Specifically, it is possible to maintain excellent antistatic performance, and it is possible to reduce the amount of addition of the antistatic agent, and it is possible to further improve the performance of preventing the occurrence of paste residue.

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

The adhesive composition of the present invention contains a copolymer comprising a copolymerizable monomer The acrylic polymer is characterized in that the copolymerizable monomer contains 50 to 95 parts by weight of (A) an alkyl group having a carbon number of C4 to C18 (methyl group) per 100 parts by weight of the acrylic polymer. An acrylate monomer, 0.1 to 10 parts by weight of a copolymerizable monomer group, (B) a hydroxyl group-containing copolymerizable monomer, and 0.1 to 1.0 part by weight of (C) a carboxyl group-containing copolymerizable monomer, 8 to 50 parts by weight of (D) polyalkylene glycol mono(meth)acrylate monomer, 0.1 to 20 parts by weight of (E) nitrogen-containing vinyl monomer having no hydroxyl group or containing alkoxy group At least one of the alkyl (meth) acrylate monomers, and the binder composition does not contain a siloxane compound, and contains (F) a difunctional or higher isocyanate compound, (G) a crosslinking catalyst, (H) a keto-enol tautomer compound, (I) an ionic compound having a melting point of 25 to 50 ° C and/or an ionic compound containing an acryl oxime group as an antistatic agent.

It is preferable to contain 0.1 to 10 parts by weight of the above (F) difunctional or higher isocyanate compound, 0.001 to 0.5 part by weight of the above (G) crosslinking catalyst, and 0.1 to 300 parts by weight, based on 100 parts by weight of the acrylic polymer. The above (H) keto-enol tautomer compound, and the above (I) antistatic agent contains an ionic compound having a melting point of 25 to 50 ° C in the above binder composition and in the above copolymer The copolymerized propylene group-containing ionic compound is 0.01 to 5.0 parts by weight in total, and the (D) polyalkylene glycol mono(meth) acrylate monomer constituting the polyalkylene glycol chain alkylene oxide The average number of repetitions is 3 to 14, the diester portion in the monomer is 0.3% or less, the water content is 0.1% or less, and the solubility in water is 2% or less in the state of 20% aqueous solution.

As the (A) alkyl group, the number of carbon atoms is C4 to C18 (methyl) Examples of the acrylate monomer include butyl (meth)acrylate, isobutyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, and heptyl (meth)acrylate. Octyl methacrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, (meth)acrylic acid Anthracene ester, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, (meth)acrylic acid Tetradecyl ester, pentadecyl (meth)acrylate, cetyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, Myristyl (meth)acrylate, isomyristyl (meth)acrylate, cetyl (meth)acrylate, isocetyl (meth)acrylate, stearyl (meth)acrylate, (methyl) ) Isostearyl acrylate and the like.

The (meth)acrylic acid ester monomer having a C4 to C18 carbon number of the (A) alkyl group is preferably contained in an amount of 50 to 95 parts by weight based on 100 parts by weight of the copolymerizable monomer based on 100 parts by weight of the acrylic polymer.

Examples of the (B) copolymerizable monomer having a hydroxyl group include 8-hydroxyoctyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Hydroxyalkyl (meth) acrylate such as 2-hydroxyethyl methacrylate, N-hydroxy(meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N-hydroxyethyl A (meth) acrylamide containing a hydroxyl group, such as a (meth) acrylamide.

Preferably, it is selected from the group consisting of 8-hydroxyoctyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, N- Hydroxy (meth) acrylamide, N-hydroxymethyl (meth) propylene oxime At least one or more of an amine and N-hydroxyethyl (meth) acrylamide.

The copolymerizable monomer preferably contains (B) a copolymerizable monomer having a hydroxyl group in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the acrylic polymer.

Preferably, the (C) carboxyl group-containing copolymerizable monomer is selected from the group consisting of (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, and 2-(methyl) hexahydrophthalate. ) propylene methoxyethyl ester, 2-(methyl) propylene methoxy propyl hexahydrophthalate, 2-(methyl) propylene methoxyethyl phthalate, 2- succinic acid Base) propylene methoxyethyl ester, 2-(methyl) propylene methoxyethyl maleate, carboxy polycaprolactone mono (meth) acrylate, tetrahydrophthalic acid 2-(methyl) At least one or more of propylene methoxyethyl esters.

The copolymerizable monomer preferably contains (C) a carboxyl group-containing copolymerizable monomer in an amount of 0.1 to 1.0 part by weight based on 100 parts by weight of the acrylic polymer.

As the (D) polyalkylene glycol mono(meth)acrylate monomer, one of a plurality of hydroxyl groups of the polyalkylene glycol is esterified in the form of (meth)acrylate The compound can be. Since the (meth) acrylate group is a polymerizable group, it can be copolymerized with the main agent polymer. The other hydroxyl group may be maintained as OH, or may be a saturated carboxylic acid ester such as an alkyl ether such as methyl ether or diethyl ether or an acetate.

Examples of the alkylene group of the polyalkylene glycol include a vinyl group, a propenyl group, and a butenyl group, but are not limited thereto. The polyalkylene glycol may be a copolymer of two or more kinds of polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Examples of the copolymer of polyalkylene glycol include polyethylene glycol-polypropylene glycol and polyethylene glycol. Glycol-polybutylene glycol, polypropylene glycol-polybutylene glycol, polyethylene glycol-polypropylene glycol-polybutylene glycol, etc., and the copolymer may be a block copolymer or a random copolymer.

Preferably, the average repeating number of the alkylene oxide constituting the polyalkylene glycol mono(meth)acrylate monomer of the (D) polyalkylene glycol chain is from 3 to 14. "Average repeat number of alkylene oxide" means olefination in a portion of the "polyalkylene glycol chain" contained in the molecular structure of the (D) polyalkylene glycol mono(meth)acrylate monomer. The average number of oxygen unit repeats.

The (D) polyalkylene glycol mono(meth)acrylate monomer preferably has a diester moiety of 0.3% or less, a water content of 0.1% or less, and a solubility in water of 20%. The haze value in the aqueous solution state is 2% or less.

The "diester moiety in the monomer" means the content ratio of the polyalkylene glycol di(meth)acrylate contained in the (D) polyalkylene glycol mono(meth)acrylate monomer ( weight%).

The "water content rate" means the content (% by weight) of water contained in the (D) polyalkylene glycol mono(meth)acrylate monomer.

The "haze value in the state of a 20% aqueous solution" means the turbidity value (%) of the aqueous solution in the state in which the (D) polyalkylene glycol mono(meth)acrylate monomer is an aqueous solution of 20% by weight. ). In other words, the (D) polyalkylene glycol mono(meth)acrylate monomer not only has water solubility (solubility in water) as a 20% aqueous solution, but also requires a haze value (%) in a 20% aqueous solution. Low (less white turbidity).

Incidentally, in the present specification, the turbidity value of the 20% aqueous solution is a value measured by a turbidimeter by adding the aqueous solution to a quartz cell having an optical path length of 10 mm. The degree of hydrophilicity of the index (D) polyalkylene glycol mono(meth)acrylate monomer is to select no white turbidity even at high concentrations. The solution is introduced by a monomer having high hydrophilicity.

As the (D) polyalkylene glycol mono(meth)acrylate monomer, it is preferably selected from polyalkylene glycol mono(meth)acrylates, methoxypolyalkylene glycols (methyl groups) At least one of an acrylate and an ethoxylated polyalkylene glycol (meth) acrylate.

More specifically, polyethylene glycol mono- (meth) acrylate, polypropylene glycol mono (meth) acrylate, polybutylene glycol - mono (meth) acrylate, polyethylene glycol - Polypropylene glycol-mono(meth)acrylate, polyethylene glycol-polybutylene glycol-mono(meth)acrylate, polypropylene glycol-polybutylene glycol-mono(meth)acrylate, polyethylene glycol- Polypropylene glycol-polybutylene glycol-mono(meth)acrylate; methoxypolyethylene glycol-(meth)acrylate, methoxypolypropylene glycol-(meth)acrylate, methoxy polybutylene Alcohol-(meth) acrylate, methoxy-polyethylene glycol-polypropylene glycol-(meth) acrylate, methoxy-polyethylene glycol-polybutylene glycol-(meth) acrylate, A Oxy-polypropylene glycol-polybutylene glycol-(meth)acrylate, methoxy-polyethylene glycol-polypropylene glycol-polybutylene glycol-(meth)acrylate; ethoxylated polyethylene glycol- (Meth) acrylate, ethoxypolypropylene glycol-(meth) acrylate, ethoxylated polybutylene glycol-(meth) acrylate, ethoxy-polyethylene glycol-polypropylene glycol-(methyl Acrylate, ethoxy-polyethylene glycol-polybutylene glycol-(meth)acrylate Ethoxy - glycol - polyethylene glycol - (meth) acrylate, ethoxy - polyethylene glycol - polypropylene glycol - polyethylene glycol - (meth) acrylate.

Preferably, the copolymerizable monomer contains (D) a polyalkylene glycol mono(meth)acrylate monomer in an amount of 8 to 50 parts by weight based on 100 parts by weight of the acrylic polymer.

The (E-1) nitrogen-containing vinyl monomer in (E) may, for example, be a vinyl monomer containing a guanamine bond, a vinyl monomer containing an amino group, or an ethylene having a heterocyclic structure containing nitrogen. Base monomer and the like. More specifically, N-vinyl-2-pyrrolidone, N-vinylpyrrolidone, methylvinylpyrrolidone, N-vinylpyridine, N-vinylacridone, N-vinylpyrimidine, N -vinylpyridazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, N- N-vinyl substituted cyclic nitrogen-vinyl compound having a heterocyclic structure such as vinyl dodecylamine; N-(methyl)propenylmorpholine, N-(methyl)propenylpyridazine , N-(methyl) propylene decyl aziridine, N-(methyl) propylene fluorenyl azetidine, N-(methyl) propylene decyl pyrrolidine, N-(methyl) propylene fluorenyl N-(meth)acryloyl fluorenyl substituted with a heterocyclic structure such as acridine, N-(methyl) propylene fluorenyl azepane or N-(methyl) propylene fluorenyl azepine Cyclic nitrogen-vinyl compound; N-cyclohexylmaleimide, N-phenylmaleimide, etc., cyclic nitrogen ethylene having a heterocyclic structure having a nitrogen atom and an ethylenically unsaturated bond in the ring. Base compound; (meth) acrylamide, N-methyl (meth) propylene oxime An unsubstituted or monoalkyl-substituted (meth) acrylamide such as N-isopropyl (meth) acrylamide or N-tert-butyl (meth) acrylamide; N,N-dimethyl (Meth) acrylamide, N,N-diethyl(meth) acrylamide, N,N-dipropyl acrylamide, N,N-diisopropyl(meth) acrylamide, N,N-dibutyl(meth)acrylamide, N-ethyl-N-methyl(meth)acrylamide, N-methyl-N-propyl(meth)acrylamide, N -Dialkyl substituted (meth) acrylamide such as methyl-N-isopropyl (meth) acrylamide; N,N-dimethylaminomethyl (meth) acrylate, N, N-di Methylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (A Acrylate, N,N-dimethylaminoisopropyl (meth) acrylate, N,N-dimethylaminobutyl (meth) acrylate, N,N-diethylaminomethyl (methyl) Acrylate, N,N-diethylaminoethyl (meth) acrylate, N-ethyl-N-methylaminoethyl (meth) acrylate, N-methyl-N-propylamino Ethyl (meth) acrylate, N-methyl-N-isopropylaminoethyl (meth) acrylate, N, N-dibutylaminoethyl (meth) acrylate, tert-butylamino Dialkylamino (meth) acrylate such as ethyl (meth) acrylate; N,N-dimethylaminopropyl (meth) acrylamide, N,N-diethylaminopropyl (methyl) Acrylamide, N,N-dipropylaminopropyl(meth)acrylamide, N,N-diisopropylaminopropyl(meth)acrylamide, N-ethyl-N-methyl Aminopropyl (meth) acrylamide, N-methyl-N-propylaminopropyl (meth) acrylamide, N-methyl-N-isopropylaminopropyl (meth) propylene oxime N,N-dialkyl substituted aminopropyl (meth) acrylamide such as amine; N-vinylformamide, N-vinylacetamide, N-vinyl-N-methylacetamide, etc. N-vinyl carboxylic acid amide N-methoxymethyl (meth) acrylamide, N-ethoxyethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, diacetone propylene oxime A (meth) acrylamide such as an amine or N,N-methylenebis(meth)acrylamide or an unsaturated carboxylic acid nitrile such as (meth)acrylonitrile.

The (E-1) nitrogen-containing vinyl monomer is preferably a monomer having no hydroxyl group, and more preferably a monomer not containing a hydroxyl group and a carboxyl group. As such a monomer, preferred are the monomers exemplified above, for example, an acrylic monomer containing an N,N-dialkyl substituted amino group and/or an N,N-dialkyl substituted decylamino group; N-vinyl- N-vinyl substituted indoleamines such as 2-pyrrolidone, N-vinyl caprolactam, N-vinyl-2-acridone, N-(methyl)propenylmorpholine, N-(A Acetylpyridinium An N-(meth)acryloyl group such as a rotary group is substituted with a cyclic amine.

Examples of the (E-2) alkoxy group-containing alkyl (meth) acrylate monomer in (E) include 2-methoxyethyl (meth)acrylate and 2-(meth)acrylate. Ethoxyethyl ester, 2-propoxyethyl (meth)acrylate, 2-isopropoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, (methyl) 2-methoxypropyl acrylate, 2-ethoxypropyl (meth)acrylate, 2-propoxypropyl (meth)acrylate, 2-isopropoxypropyl (meth)acrylate, ( 2-butoxypropyl methacrylate, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 3-propoxypropyl (meth) acrylate , 3-isopropoxypropyl (meth)acrylate, 3-butoxypropyl (meth)acrylate, 4-methoxybutyl (meth)acrylate, 4-ethoxy (meth)acrylate Butyl ester, 4-propoxybutyl (meth)acrylate, 4-isopropoxybutyl (meth)acrylate, 4-butoxybutyl (meth)acrylate, and the like.

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

Preferably, the copolymerizable monomer contains (E) a nitrogen-containing vinyl monomer having no hydroxyl group or an alkyl group having an alkoxy group in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic polymer. At least one of acrylate monomers. One or two or more (E-1) nitrogen-containing vinyl monomers not containing a hydroxyl group and (E-2) an alkoxy-containing alkyl (meth) acrylate monomer may be used in combination.

The (F) difunctional or higher isocyanate compound may be at least one or two or more selected from the group consisting of polyisocyanate compounds having at least two or more isocyanate (NCO) groups in one molecule. Polyisocyanate compound The aliphatic isocyanate, the aromatic isocyanate, the acyclic isocyanate, the alicyclic isocyanate, and the like may be classified, and may be any.

Examples of the trifunctional or higher isocyanate compound include a biuret modified product (a compound having two NCO groups in one molecule), a modified isocyanurate modified product, and trihydroxymethylpropane. (TMP) an adduct (polyol modified product) of a trivalent or higher polyvalent alcohol (a compound having at least three or more OH groups in one molecule) such as glycerin. As the (F) difunctional or higher isocyanate compound, only a trifunctional isocyanate compound may be used, or only a difunctional isocyanate compound may be used. Further, a trifunctional isocyanate compound and a difunctional isocyanate compound may also be used in combination.

As the trifunctional isocyanate compound, an isocyanurate body selected from a hexamethylene diisocyanate compound, an isocyanurate body of an isophorone diisocyanate compound, and an adduct of a hexamethylene diisocyanate compound are preferable. An adduct of an isophorone diisocyanate compound, a biuret of a hexamethylene diisocyanate compound, a biuret of an isophorone diisocyanate compound, an isocyanurate body of a toluene diisocyanate compound An isocyanurate body of a benzene dimethylene diisocyanate compound, an isocyanurate body of a hydrogenated benzene dimethylene diisocyanate compound, an adduct of a tolylene diisocyanate compound, benzene dimethylene diisocyanate At least one or more of an adduct of a compound and an adduct of a hydrogenated benzene dimethylene diisocyanate compound.

The difunctional isocyanate compound is preferably an acyclic aliphatic isocyanate compound, which is a compound formed by reacting a diisocyanate compound with a diol compound. For example, a diisocyanate compound is represented by the general formula "O=C=N-X-N=C=O" (wherein X is a divalent group), and the formula "HO-Y-OH" is used. (When Y is a divalent group), the compound which is produced by reacting a diisocyanate compound and a diol compound in the case of a diol compound, for example, is a compound represented by the following formula Z.

[Formula 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 general formula Z represents "O=C=N-X-N=C=O". The difunctional acyclic aliphatic isocyanate compound may contain a compound in which n is 0 (a diisocyanate compound which is not reacted with respect to a diol compound), and a compound containing n as an integer of 1 or more is preferable as Must be a component. The difunctional acyclic aliphatic isocyanate compound may be a mixture of a plurality of compounds different in n in the formula Z.

The diisocyanate compound represented by the general formula "O=C=N-X-N=C=O" is an aliphatic diisocyanate. Preferably, X is an acyclic and aliphatic divalent group. The aliphatic diisocyanate preferably includes one selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and lysine diisocyanate. Or more than two.

The diol compound represented by the general formula "HO-Y-OH" is an aliphatic diol. Preferably, Y is an acyclic and aliphatic divalent group. The diol compound preferably includes 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, and 2-methyl-2-propyl-1,3-propanediol. , 2-ethyl-2-butyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2-dimethyl-1,3-propanediol monohydroxy pivalate, One or more of polyethylene glycol and polypropylene glycol.

Preferably, it is 0.1 with respect to 100 parts by weight of the acrylic polymer. The ratio of ~10 parts by weight contains (F) a difunctional or higher isocyanate compound.

In the (G) crosslinking catalyst, when the polyisocyanate compound is used as a crosslinking agent, the reaction (crosslinking reaction) of the copolymer and the crosslinking agent may function as a catalyst, and may be mentioned. An organometallic compound such as an amine compound such as a tertiary amine, a metal chelate compound, an organotin compound, an organic lead compound or an organozinc compound.

Examples of the tertiary amine include a trialkylamine, N,N,N',N'-tetraalkyldiamine, N,N-dialkylamino alcohol, triethylenediamine, morpholine derivative, pyridazine. Derivatives, etc.

The metal chelate compound is a compound in which one or more polydentate ligands L are bonded to the central metal atom M. The metal chelate compound may or may not have one or more monodentate ligands X bonded to the metal atom M. For example, when M(L) _m (X) _{n is used to} represent a general formula of a metal chelate compound having one metal atom M, m 1,n 0. When M is two or more, m of L may be the same ligand or different ligands. When n is 2 or more, n of X 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 multidentate ligand L include β -ketone such as methyl acetate, ethyl acetate, octyl acetate, acetonitrile acetate, lauryl acetate, and stearyl acetate. a β -diketone such as ester, acetamidine acetone (alias 2,4-pentanedione), 2,4-hexanedione, benzhydrazinone or the like. These are keto-enol tautomer compounds, and in the polydentate ligand L, may be an enolate (e.g., acetamidine) after deprotonation of the enol.

Examples of the monodentate ligand X include a halogen atom such as a chlorine atom or a bromine atom, and Alkyl groups such as fluorenyl, hexyl fluorenyl, 2-ethylhexyl decyl, octyl decyl, decyl, decyl, dodecyl decyl, octadecyl fluorenyl, methoxy, ethoxy, An alkoxy group such as a propoxy group, an isopropoxy group or a butoxy group.

Specific examples of the metal chelate compound include tris(2,4-pentanedionate)iron (III), triethylsulfonium iron, triacetin, titanium triacetone, acetonide, and diacetyl. Acetone zinc, aluminum triacetate, zirconium tetraethoxide, iron (III) tris(2,4-hexanedione acid), zinc bis(2,4-hexanedione acid), three (2, 4-hexanedione acid) titanium, tris(2,4-hexanedione acid)aluminum, tetrakis(2,4-hexanedione acid)zirconium or the like.

Examples of the organotin compound include a dialkyl tin oxide, a fatty acid salt of a dialkyl tin, a fatty acid salt of monovalent tin, and the like.

The (G) crosslinking catalyst is preferably a metal chelate compound or an organotin compound. As the metal chelate compound, an aluminum chelate compound, a titanium chelate compound, an iron chelate compound, a tin chelate compound or the like is preferable. The organotin is preferably at least one selected from the group consisting of dioctyltin oxide and dioctyltin dilaurate.

The (G) crosslinking catalyst is preferably contained in an amount of 0.001 to 0.5 parts by weight based on 100 parts by weight of the acrylic polymer.

Examples of the (H) keto-enol tautomer compound include methyl acetoacetate, ethyl acetate, octyl acetate, acetonitrile acetate, lauryl acetate, and ethyl acetonitrile. stearyl ester β - keto ester, acetyl acetone, hexane-2,4-dione, benzoyl acetone and the like β - diketone. (H) a keto-enol tautomer compound in an adhesive composition having a polyisocyanate compound as a crosslinking agent, by an isocyanate group possessed by a block crosslinking agent, thereby capable of suppressing the addition of a crosslinking agent Excessive viscosity rise or gelation of the adhesive composition can extend the pot life of the adhesive composition.

The (H) keto-enol tautomer compound is particularly preferably at least one selected from the group consisting of acetonitrile and ethyl acetate.

The (H) keto-enol tautomer compound is preferably contained in an amount of 0.1 to 300 parts by weight based on 100 parts by weight of the acrylic polymer.

Since the (H) keto-enol tautomer compound has an effect of suppressing crosslinking in contrast to the (G) crosslinking catalyst, it is preferred to appropriately set the (H) keto-enol tautomer compound relative to (G) The ratio of cross-linking catalyst. In order to prolong the pot life of the binder composition and improve storage stability, it is preferred that the weight ratio (H)/(G) of the (G) crosslinking catalyst to the (H) keto-enol tautomer compound is 70 to 1000. .

Preferably, the (I) antistatic agent is (I-1) an ionic compound having a melting point of 25 to 50 ° C and/or (I-2) an ionic compound containing an acryl fluorenyl group.

In the present invention, as the (I) antistatic agent, (I-1) an ionic compound having a melting point of 25 to 50 ° C is added to the copolymer, and/or (I-2) an ion containing an acrylonitrile group is used. The compound is copolymerized in the copolymer. Since these (I) antistatic agents have a low melting point and have a long-chain alkyl group, it is presumed that the affinity with the acrylic copolymer is high.

Examples of the (I) antistatic agent include an antistatic agent contained in the binder composition and an antistatic agent copolymerized in the above copolymer. It is preferable that the (I-1) ionic compound having a melting point of 25 to 50 ° C and the (I-2) copolymerized in the copolymer are contained in the binder composition with respect to 100 parts by weight of the acrylic polymer. The thiol group-containing ionic compound contains (I) an antistatic agent in a total amount of 0.01 to 5.0 parts by weight.

The (I-1) ionic compound having a melting point of 25 to 50 ° C is an ionic compound having a cation and an anion, and examples of the cation include a pyridinium cation, an imidazolium cation, a pyrimidine cation, a pyrazolium cation, and a pyrrole. a nitrogen-containing phosphonium cation such as an alkane cation or an ammonium cation or a phosphonium cation or a phosphonium cation, and the anion is a hexafluorophosphate (PF ₆ ^- ), a thiocyanate (SCN ^- ), an alkylbenzenesulfonate (RC ₆ H ₄ SO ₃ ^- ), perchlorate (ClO ₄ ^- ), tetrafluoroborate (BF ₄ ^- ), bis(fluorosulfonyl)imide salt (FSI), bis(trifluoromethanesulfonyl) A compound of an inorganic or organic anion such as an amine salt (TFSI) or a triflate (TF). It is preferably a solid at normal temperature (for example, 25 ° C), and an ionic compound having a melting point of 25 to 50 ° C can be obtained by selecting the chain length of the alkyl group, the position and number of the substituents, and the like. The cation is preferably a quaternary nitrogen-containing cerium cation, and examples thereof include a quaternary pyridinium cation such as a 1-alkylpyridinium group (the carbon atom at the 2nd to 6th position may have a substituent or may be unsubstituted), and a 1,3-dialkylimidazolium group. A quaternary ammonium cation such as a quaternary imidazolium cation or a tetraalkylammonium such as a (2, 4, or 5 carbon atom may have a substituent or may be unsubstituted).

It is preferable to contain (I-1) an ionic compound having a melting point of 25 to 50 ° C in an amount of 0.01 to 5.0 parts by weight based on 100 parts by weight of the acrylic polymer.

The ionic compound containing an acryl fluorenyl group (I-2) is an ionic compound having a cation and an anion, and the cation is (meth) propylene decyloxyalkyltrialkylammonium [R ₃ N ⁺ - C _n H _2n -OCOCQ=CH ₂ , wherein Q=H or CH ₃ , R=alkyl] and the like (meth)acryloyl group-containing cation, anion is hexafluorophosphate (PF ₆ ^- ), thiocyanate Acid salt (SCN ^- ), organic sulfonate (RSO ₃ ^- ), perchlorate (ClO ₄ ^- ), tetrafluoroborate (BF ₄ ^- ), imine salt containing F (R ^F ₂ N ^- ) A compound such as an inorganic or organic anion. As the (R ^F ₂ N ^-) containing F ^F R & lt imine salt, trifluoromethanesulfonic include acyl, pentafluoroethane sulfonic acyl and the like perfluoroalkyl sulfonic acyl or a sulfo-fluoro-acyl. Examples of the imine salt containing F include bis(fluorosulfonyl)imide salt [(FSO ₂ ) 2N ^- ], bis(trifluoromethanesulfonyl)imide salt [(CF ₃ SO ₂ ) 2N. ^{- a} bissulfonimidoimine salt such as bis(pentafluoroethanesulfonyl)imide salt [(C ₂ F ₅ SO ₂ ) ₂ N-].

Preferably, the ionic compound containing the propylene fluorenyl group (I-2) is copolymerized in an amount of 0.01 to 5.0 parts by weight based on 100 parts by weight of the acrylic polymer.

Specific examples of the (I) antistatic agent are not particularly limited, and specific examples of the (I-1) ionic compound having a melting point of 25 to 50 ° C include 1-octylpyridinium hexafluorophosphate and 1 - mercaptopyridinium hexafluorophosphate, 2-methyl-1-dodecylpyridinium hexafluorophosphate, 1-octylpyridinium dodecylbenzenesulfonate, 1-dodecylpyridine Thiocyanate, 1-dodecylpyridinium dodecylbenzenesulfonate, 4-methyl-1-octylpyridinium hexafluorophosphate, and the like. Further, specific examples of the (I-2) ionic compound containing an acryloyl group include dimethylaminomethyl (meth) acrylate hexafluorophosphate methyl salt [(CH ₃ ) ₃ N ⁺ CH ₂ OCOCQ=CH ₂ . PF ₆ ^- , wherein, Q=H or CH ₃ ], dimethylaminoethyl (meth) acrylate bis(trifluoromethanesulfonyl) quinone imine methyl salt [(CH ₃ ) ₃ N ⁺ (CH ₂ ) ₂ OCOCQ=CH ₂ . (CF ₃ SO ₂ ) ₂ N ^- , wherein, Q=H or CH ₃ ], dimethylaminomethyl methacrylate bis(fluorosulfonyl) quinone imine methyl salt [(CH ₃ ) ₃ N ⁺ CH ₂ OCOCQ=CH ₂ . (FSO ₂ ) ₂ N ^- , wherein Q = H or CH ₃ 〕 and the like.

Further, as other components, a copolymerizable (meth)acrylic monomer, a (meth)acrylamide monomer, a dialkyl-substituted acrylamide monomer, a surfactant, and a curing agent containing an alkylene oxide can be appropriately blended. A known additive such as an accelerator, a plasticizer, a filler, a curing retarder, a processing aid, an anti-aging agent, and an antioxidant. These may be used alone or in combination of two or more.

However, it is preferred that the adhesive composition of the present invention does not contain a oxoxane compound. Here, the siloxane compound refers to a compound having a siloxane structure, and includes a modified body such as a polyether-modified siloxane compound. In the present invention, by blending a predetermined amount of the (D) polyalkylene glycol mono(meth)acrylate monomer with a binder, the hydrophilicity is improved even if the azide-containing compound is not contained, so that it can be formed. A layer of adhesive that is excellent in antistatic properties.

The copolymer of the main agent which can be used in the adhesive composition of the present invention can be synthesized by polymerizing a monomer having a (A) alkyl group having a carbon number of C4 to C18 (methyl). An acrylate monomer, (B) a copolymerizable monomer having a hydroxyl group, (C) a carboxyl group-containing copolymerizable monomer, (D) a polyalkylene glycol mono(meth)acrylate monomer, and (E) A nitrogen-containing vinyl monomer or alkoxy-containing alkyl (meth) acrylate monomer which does not contain a hydroxyl group. The polymerization method of the copolymer is not particularly limited, and a suitable polymerization method such as solution polymerization or emulsion polymerization can be used.

When (I-2) an ionic compound containing an acrylonitrile group is used as the (I) antistatic agent, the copolymer of the main agent which can be used in the binder composition of the present invention can be obtained by making (I-2) propylene The thiol-based ionic compound is synthesized by polymerization of a monomer having a (A) alkyl group having a C4 to C18 (meth) acrylate monomer and (B) a hydroxyl group-containing copolymerizable product. a monomer, (C) a carboxyl group-containing copolymerizable monomer, (D) a polyalkylene glycol mono(meth)acrylate monomer, and (E) a nitrogen-containing vinyl monomer having no hydroxyl group or An alkoxy-containing alkyl (meth) acrylate monomer.

The binder composition of the present invention may further contain (F) a difunctional or higher isocyanate compound to the above copolymer by not containing a decane compound. The (G) crosslinking catalyst and the (H) keto-enol tautomer compound are further prepared by appropriately blending any of the additives. When the (I-2) acryl-containing ionic compound is polymerized in the copolymer of the main component, (I-1) an ionic compound having a melting point of 25 to 50 ° C may be further added to the copolymer. It is also possible not to add.

In the production of the copolymer of the main component, in order to reduce the incorporation of moisture into the binder composition, it is preferred to carry out the polymerization reaction under anhydrous conditions using solution polymerization using an anhydrous organic solvent. In particular, since the (D) polyalkylene glycol mono(meth)acrylate monomer has high hydrophilicity, it is preferred to use a compound having a low water content.

In order to avoid an increase in the viscosity of the binder composition, it is preferred that each monomer used in the production of the copolymer of the main component is reduced in a polyfunctional (difunctional or higher) single sheet capable of functioning as a crosslinking agent. The amount of body. In particular, since the corresponding diester moiety of the (D) polyalkylene glycol mono(meth)acrylate monomer is a di(meth)acrylate of a difunctional monomer, it is preferred to use a small diester moiety. Compound.

The copolymer is preferably an acrylic polymer, and preferably contains (meth) acrylate monomer, (meth) acrylate, (methyl) in an amount of 50 to 100 parts by weight based on 100 parts by weight of the acrylic polymer. An acrylic monomer such as acrylamide.

Further, the acrylic polymer preferably has an acid value of 0.01 to 8.0. Thereby, the stain property can be improved, and the performance for preventing the occurrence of paste residue can be improved.

Here, the "acid value" is one of the indexes indicating the content of the acid, and is expressed by the number of mg of potassium hydroxide required to neutralize 1 g of the carboxyl group-containing polymer.

It is preferable that the adhesive layer obtained by crosslinking the above-mentioned binder composition has an adhesive force at a low peeling speed of 0.3 m/min of 0.04 to 0.2 N/25 mm, and an adhesive force at a high peeling speed of 30 m/min. 2.0N/25mm or less. Thereby, the adhesive force can be made small by the peeling speed, and even if it peels at high speed, it can peel rapidly. Further, since it is re-bonded, even if the surface protective film is peeled off, it does not require an excessive force, and it is easy to peel off from the adherend.

The surface resistivity of the adhesive layer obtained by crosslinking the above-mentioned binder composition is preferably 9.0×10 ⁺¹¹ Ω/□ or less, and the peeling tape voltage is ±0 to 0.5 kV. Incidentally, in the present invention, "±0 to 0.5 kV" means 0 to -0.5 kV and 0 to +0.5 kV, that is, -0.5 to +0.5 kV. If the surface resistivity is large, the performance of static electricity generation due to charging at the time of peeling is inferior. Therefore, by making the surface resistivity sufficiently small, it is possible to reduce the peeling band voltage generated by the static electricity generated when the adherend is peeled off from the adhesive layer, and it is possible to suppress the influence on the electrical control circuit or the like of the adherend.

The binder layer (the binder after crosslinking) obtained by crosslinking the binder composition of the present invention preferably has a gel fraction of 95 to 100%. Thus, the gel fraction is high, so that the adhesive force does not become excessive at a low peeling speed, and the elution of the unpolymerized monomer or oligomer derived from the copolymer is lowered, and the reworkability, high temperature and high humidity can be improved. Durability, inhibiting the smudges of the adherend.

The adhesive film of the present invention is formed by forming a binder layer obtained by crosslinking the adhesive composition of the present invention on one or both sides of a resin film. Further, the surface protective film of the present invention is a surface protective film in which a binder layer obtained by crosslinking the binder composition of the present invention is formed on one surface of a resin film. For the adhesive composition of the present invention, the above-mentioned (A) to (I) are well balanced. Each component has excellent antistatic properties, excellent balance of adhesion at low peeling speed and high peeling speed, and durability and reworkability (scratch on the surface with a ballpoint pen through the adhesive layer) After the film is applied, the stain does not transfer to the adherend) and is also excellent. Therefore, it can be suitably used as a surface protective film of a polarizing plate.

As the base film of the adhesive layer and the release film (separation film) for protecting the adhesive surface, a resin film such as a polyester film or the like can be used.

Antifouling treatment using an organic fluorene-based or fluorine-based release agent, a coating agent, cerium oxide fine particles, or the like may be performed on the surface of the base film opposite to the side on which the adhesive layer of the resin film is formed. Antistatic treatment of coating, mixing, etc. of an antistatic agent.

In the release film, a release treatment is performed on the surface of the adhesive layer that is bonded to the bonding surface by an organic fluorene-based or fluorine-based release agent.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples.

<Manufacture of Acrylic Copolymer>

[Example 1]

Nitrogen gas was introduced into a reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introduction tube, and the air in the reaction apparatus was replaced with nitrogen. Thereafter, 100 parts by weight of 2-ethylhexyl acrylate, 3.0 parts by weight of 8-hydroxyoctyl acrylate, 0.2 parts by weight of acrylic acid, and polypropylene glycol monoacrylate (olefins constituting the polyalkylene glycol chain) were added to the reaction apparatus. The average number of repetitions of oxygen is n=12, the diester fraction in the monomer is 0.1%, the solubility in water is 0.8% in the state of 20% aqueous solution, and the moisture content is 0.05%) 10 weight. , N-vinylpyrrolidone 5 Parts by weight, and 60 parts by weight of a solvent (ethyl acetate). Thereafter, 0.1 part by weight of azobisisobutyronitrile was added dropwise as a polymerization initiator over 2 hours, and the mixture was reacted at 65 ° C for 6 hours to obtain an acrylic copolymer solution used in Example 1 having a weight average molecular weight of 500,000. A part of the acrylic copolymer was used as a measurement sample of an acid value to be described later.

[Examples 2 to 9 and Comparative Examples 1 to 4]

Example 2 was obtained in the same manner as in the above-described acrylic copolymer solution used in Example 1, except that the composition of the monomers was as described in (A) to (E) and (I-2) of Table 1, respectively. ~9 and the acrylic copolymer solution used in Comparative Examples 1 to 4.

<Manufacture of adhesive composition and surface protective film>

[Example 1]

After adding 1.0 part by weight of 1-octylpyridinium hexafluorophosphate and 8.5 parts by weight of acetamidine acetone to the acrylic copolymer solution of Example 1 produced as described above, Coronet HX (hexamethylene diisocyanate) was added thereto. The adhesive composition of Example 1 was obtained by stirring and mixing 2.5 parts by weight of the isocyanurate compound of the compound and 0.1 part by weight of titanium triacetate. The adhesive composition is applied onto a release film made of a polyethylene terephthalate (PET) film coated with an organic tantalum resin, and then dried at 90 ° C to remove the solvent to obtain a thickness of the adhesive layer. It is a 25 μm adhesive sheet.

Thereafter, on one side, the adhesive sheet is transferred to the polyethylene terephthalate (PET) film after the antistatic treatment and the antifouling treatment, and is opposite to the surface after the antistatic treatment and the antifouling treatment. A laminate having a "PET film/adhesive layer/release film (PET film coated with an organic oxime resin)" after the antistatic treatment and the antifouling treatment was obtained. The surface protective film of Example 1.

[Examples 2 to 9 and Comparative Examples 1 to 4]

The surfaces of Examples 2 to 9 and Comparative Examples 1 to 4 were obtained in the same manner as in the surface protective film of Example 1 except that the composition of the additive was as described in (F) to (J) of Table 2, respectively. Protective film.

In Tables 1 and 2, the mixing ratio of each component is represented by a numerical value indicating the weight fraction obtained by taking the total of the group (A) as 100 parts by weight. In Table 1, the (I-2) acryl-containing ionic compound copolymerized in the copolymer in (I) the antistatic agent is described in a different manner from the (I) antistatic agent added after the polymerization. In the column.

Further, the compound names of the abbreviations of the respective components used in Tables 1 and 2 are shown in Tables 3 and 4. Coronet (registered trademark) HX, the HL and the L are trade names of Japan Polyurethane Industry Co., Ltd., Takenate (registered trademark) D-140N, D-127N, D-110N, and D-120N are Mitsui Chemicals Co., Ltd. The trade name of the club. For the group (D) of Table 3, the value of "n" is the average number of repetitions of the alkylene oxide constituting the polyalkylene glycol chain. The value of "diester" is the diester moiety (%) in the monomer. The value of "moisture" is the moisture content rate (%). The value of "turbidity" is the haze value (%) in the state of 20% aqueous solution. Further, the values of (H)/(G) are shown in Table 5.

<Synthesis of difunctional isocyanate compound>

The difunctional isocyanate compounds of Synthesis Examples 1 to 3 were synthesized in the following manner. As shown in Table 6 and Table 7, the diisocyanate and the diol compound were mixed at a molar ratio of NCO/OH = 16, and reacted at 120 ° C for 3 hours, after which unreacted was removed under reduced pressure using a thin film evaporation apparatus. Diisocyanate gives the target difunctional isocyanate compound.

<Test method and evaluation>

The surface protective films of Examples 1 to 9 and Comparative Examples 1 to 4 were aged in an atmosphere of 23° C. and 50% RH for 7 days, and then the release film (PET film coated with an organic resin) was peeled off to make a binder. The layer was exposed and used as a measurement sample of the gel fraction and the surface resistivity.

Further, the surface protective film exposing the adhesive layer is bonded to the surface of the polarizing plate to which the liquid crystal cell is attached via the adhesive layer, and left at 50 ° C for 5 days. The autoclave treatment was carried out for 20 minutes under air pressure, and further allowed to stand at room temperature for 12 hours, and this was used as a measurement sample for the adhesive force, the peeling tape voltage, the reworkability, and the durability.

<gel fraction>

After the aging was completed, the quality of the measurement sample before bonding to the polarizing plate was accurately measured, immersed in toluene for 24 hours, and then filtered through a 200-mesh wire mesh. Thereafter, the filtrate was dried at 100 ° C for 1 hour, and the quality of the residue was accurately measured, and the gel fraction of the binder layer (adhesive after crosslinking) was calculated according to the following formula.

Gel fraction (%) = insoluble portion quality (g) / binder quality (g) × 100

<Adhesion>

The measurement sample obtained above (the sample obtained by bonding the 25 mm-wide surface protection film to the surface of the polarizing plate) was used in a tensile tester at a low peeling speed (0.3 m/min) in the 180° direction. Peeling was performed at a high peeling speed (30 m/min), and the measured peeling strength was taken as the adhesive force (N/25 mm).

<surface resistivity>

After the aging, before the bonding to the polarizing plate, the release film (the PET film coated with the organic resin) was peeled off to expose the adhesive layer, and the adhesive layer was measured using a resistivity meter HIRESTA UP-HT450 (manufactured by Mitsubishi Chemical Analytech). Surface resistivity (Ω/□).

<Peel strip voltage>

When the measurement sample obtained above was peeled off by 180° at a tensile speed of 30 m/min, the voltage generated by charging the polarizing plate was measured using a high-precision electrostatic sensor SK-035 and SK-200 (manufactured by Keyence Co., Ltd.). Voltage), the maximum value of the measured value is taken as the peeling strip voltage (kV).

<Reworkability>

After the surface protective film of the measurement sample obtained above was scraped with a ballpoint pen (loading 500 g, three round trips), the surface protective film was peeled off from the polarizing plate, and the surface of the polarizing plate was observed to confirm that the stain did not transfer to the polarizing plate. In the evaluation target standard, the case where the stain was not transferred to the polarizing plate was evaluated as "○", and it was confirmed that the stain was scraped to at least a part along the scratching of the track by the ballpoint pen, and it was evaluated as "△", and the confirmation was used. The ballpoint pen scratched the track and the stain was transferred, and it was confirmed that the adhesive was also detached from the surface of the adhesive as "x".

<Durability>

The measurement sample obtained above was allowed to stand in an atmosphere of 60° C. and 90% RH for 250 hours, and then taken out at room temperature. After further standing for 12 hours, the adhesion was measured and compared with the initial adhesion, and no significant increase was confirmed. Case. In the evaluation target standard, the case where the adhesive strength after the test was 1.5 times or less of the initial adhesion force was evaluated as "○", and the case where the adhesion was more than 1.5 times was evaluated as "x".

The evaluation results are shown in Table 8. Incidentally, the surface resistivity is recorded in a manner in which "m × 10 ^{+ n} " is referred to as "mE + n" (where m is an arbitrary real value and n is a positive integer).

The surface protective film of Examples 1 to 9 had an adhesive force of 0.04 to 0.2 N/25 mm at a low peeling speed of 0.3 m/min, and an adhesive force of 2.0 N/25 mm or less at a high peeling speed of 30 m/min. The resistivity is 9.0×10 ⁺¹¹ Ω/□ or less, and the peeling tape voltage is ±0 to 0.5 kV. After the surface protective film is scraped with a ballpoint pen via the adhesive layer, the stain is not transferred to the adherend at 60 ° C. The durability was also excellent when placed in an atmosphere of 90% RH for 250 hours.

That is, it satisfies (1) maintaining the balance of the adhesive force at the low-speed peeling speed and the high-speed peeling speed, (2) preventing the occurrence of paste residue, (3) excellent antistatic property, and (4) reworkability. All required performance.

Since the surface protective film of Comparative Example 1 does not contain (F) a difunctional or higher isocyanate compound, (G) a crosslinking catalyst, or a (H) keto-enol tautomer compound, the gel fraction is 0%. The low peeling speed of 0.3 m/min and the high peeling speed of 30 m/min are small, the surface resistivity and the peeling strip voltage are high, and the workability and durability are poor.

The (D) polyalkylene glycol mono(meth)acrylate monomer of the surface protective film of Comparative Example 2 has a large diester moiety, a high water content, and low solubility in water, and contains (J) 矽. Since the oxyalkylene compound has a low peeling speed of 0.3 m/min and a high peeling speed of 30 m/min, the adhesive force is too large, the surface resistivity and the peeling tape voltage are high, and the durability is poor.

The (D) polyalkylene glycol mono(meth)acrylate monomer of the surface protective film of Comparative Example 3 has a large diester moiety, a high water content, and solubility in water. Since it is low, the application period is too short, and since it is gelled before coating, it cannot be coated.

The composition of the surface protective film of Comparative Example 4 (D) The polyalkylene glycol monoalkyl (meth) acrylate monomer has a large average number of repeating alkylene oxides and a large number of diesters. The water content is high, the solubility in water is low, and the (G) crosslinking catalyst and the (H) keto-enol tautomer compound are not contained, so that the polymerizability is poor and the viscosity is poor and the coating cannot be applied.

According to this, in the surface protective films of Comparative Examples 1 to 4, it is impossible to simultaneously satisfy (1) maintaining the balance of the adhesive force at a low peeling speed and a high peeling speed, and (2) preventing the occurrence of paste residue, (3) Excellent antistatic properties and (4) all required performance for reworkability.

Claims (14)

A binder composition comprising an acrylic polymer composed of a copolymer of a copolymerizable monomer, wherein the copolymerizable monomer contains 50 to 95 parts by weight based on 100 parts by weight of the acrylic polymer. (A) a (meth) acrylate monomer having an alkyl group having a C4 to C18 carbon number, 0.1 to 10 parts by weight of a copolymerizable monomer group, and (B) a hydroxyl group-containing copolymerizable monomer, 0.1 ~1.0 parts by weight of (C) carboxyl group-containing copolymerizable monomer, 8 to 50 parts by weight of (D) polyalkylene glycol mono(meth)acrylate monomer, 0.1 to 20 parts by weight (E) At least one of a nitrogen-containing vinyl monomer or an alkoxy group-containing alkyl (meth) acrylate monomer not containing a hydroxyl group, and the binder composition does not contain a siloxane compound, and contains F) a difunctional or higher isocyanate compound, (G) a crosslinking catalyst, (H) a keto-enol tautomer compound, (I) an ionic compound having an melting point of 25 to 50 ° C as an antistatic agent and/or An ionic compound containing an acrylonitrile group. The adhesive composition according to claim 1, wherein the (F) difunctional or higher isocyanate compound is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the acrylic polymer. 0.001 to 0.5 parts by weight of the (G) crosslinking catalyst, 0.1 to 300 parts by weight of the (H) keto-enol tautomer compound, and further, the (I) antistatic agent is bonded The total amount of the ionic compound having a melting point of 25 to 50 ° C and the propylene compound containing propylene sulfonate copolymerized in the copolymer is 0.01 to 5.0 parts by weight. The (D) polyalkylene glycol mono(meth)acrylate monomer has an average number of repeating alkylene oxides constituting the polyalkylene glycol chain of 3 to 14, and the diester moiety in the monomer is 0.3% or less, the water content rate is 0.1% or less, and the solubility in water is 2% or less in a 20% aqueous solution state. The adhesive composition according to claim 1 or 2, wherein the (G) crosslinking catalyst is a crosslinking catalyst of a metal chelate, and the crosslinking catalyst of the (G) metal chelate compound The weight ratio (H)/(G) to the (H) keto-enol tautomer compound is from 70 to 1,000. The adhesive composition according to any one of claims 1 to 3, wherein the (B) hydroxyl group-containing copolymerizable monomer is selected from the group consisting of 8-hydroxyoctyl (meth)acrylate, 6-hydroxyhexyl methacrylate, 4-hydroxybutyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, N-hydroxy (meth) acrylamide, N-hydroxymethyl (A) At least one of acrylamide and N-hydroxyethyl (meth) acrylamide. The adhesive composition according to any one of claims 1 to 4, wherein the (C) carboxyl group-containing copolymerizable monomer is selected from the group consisting of (meth)acrylic acid and (meth)acrylic acid carboxyl group. Ethyl ester, carboxy amyl (meth) acrylate, 2-(meth) propylene methoxyethyl hexahydrophthalic acid, 2-(methyl) propylene methoxy propyl hexahydrophthalic acid, 2-(Methyl)acryloxyethyl phthalate, 2-(meth) propylene methoxyethyl succinic acid, 2-(methyl) propylene methoxyethyl maleic acid, carboxyl group At least one of caprolactone mono(meth)acrylate and 2-(meth)acryloxyethyltetrahydrophthalic acid. The adhesive composition according to any one of claims 1 to 5, wherein Wherein the (D) polyalkylene glycol mono(meth)acrylate monomer is selected from the group consisting of polyalkylene glycol mono(meth)acrylates, methoxypolyalkylene glycols (A) At least one of acrylate and ethoxypolyalkylene glycol (meth) acrylate. The adhesive composition according to any one of claims 1 to 6, wherein the adhesive composition has a gel fraction of 95 to 100% after crosslinking. The binder composition according to any one of claims 1 to 7, wherein the (F) difunctional or higher isocyanate compound is an acyclic isocyanate compound, which is an acyclic aliphatic isocyanate compound. Is a compound formed by reacting a diisocyanate compound with a diol compound, and is an aliphatic diisocyanate as a diisocyanate compound, and is selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, and three One of methylhexamethylene diisocyanate and lysine diisocyanate, as a diol compound, including a group selected from the group consisting of 2-methyl-1,3-propanediol and 2,2-dimethyl-1,3-propanediol , 2-methyl-2-propyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2- One of dimethyl-1,3-propanediol monohydroxy pivalate, polyethylene glycol, and polypropylene glycol, as a trifunctional isocyanate compound, including an isocyanurate body of a hexamethylene diisocyanate compound, Isocyanurate body of phorone diisocyanate compound, hexamethylene diisocyanate An adduct of an ester compound, an adduct of an isophorone diisocyanate compound, a biuret of a hexamethylene diisocyanate compound, a biuret of an isophorone diisocyanate compound, or a toluene diisocyanate compound Isocyanurate body, isocyanurate body of benzene dimethylene diisocyanate compound, hydrogenated benzodiamidylene diiso An isocyanurate body of an cyanate compound, an adduct of a tolylene diisocyanate compound, an adduct of a benzene dimethylene diisocyanate compound, and an adduct of a hydrogenated benzene dimethylene diisocyanate compound. The adhesive composition according to any one of claims 1 to 8, wherein the adhesive layer obtained by crosslinking the adhesive composition has a low peeling speed of 0.3 m/min. The force is 0.04 to 0.2 N/25 mm, and the adhesive force at a high peeling speed of 30 m/min is 2.0 N/25 mm or less. The adhesive composition according to any one of claims 1 to 9, wherein the adhesive layer obtained by crosslinking the adhesive composition has a surface resistivity of 9.0 × 10 ^{+ 11} Ω / □ Hereinafter, the peeling tape voltage is ±0 to 0.5 kV. An adhesive film obtained by crosslinking a pressure-sensitive adhesive composition according to any one of claims 1 to 10, which is formed on one surface or both surfaces of a resin film. A surface protective film obtained by crosslinking a pressure-sensitive adhesive composition according to any one of claims 1 to 10, which is formed on one surface of a resin film, After the adhesive layer is scratched on the surface protective film with a ballpoint pen, the stain does not transfer to the adherend. The surface protective film according to claim 12, which is used as a surface protective film of a polarizing plate. The surface protection film according to claim 13, wherein the antistatic treatment and the antifouling treatment are performed on the side opposite to the side on which the adhesive layer of the resin film is formed.