JP2019104244A - Laminate - Google Patents

Abstract

To provide a laminate that can maintain antistatic performance even when receiving an electric shock by static electricity.SOLUTION: The present invention provides a laminate having an antistatic layer on at least one side of a substrate film, the antistatic layer composed of a coating composition containing an organic conductive material (a) and fine particles (b) with an average particle size of 10-500 nm, and the coating composition containing the fine particles (b) of 10-50 wt.%. A thickness A(nm) of the antistatic layer and an average particle size B(nm) of the fine particles (b) satisfy the relationship of 1<B/A.SELECTED DRAWING: None

Description

The present invention relates to a laminate. In particular, the present invention relates to a laminate resistant to electrostatic shock.

Plastic products have high electrical insulation, and generate static electricity due to contact, peeling, and friction. This static electricity results in the adhesion of dust to plastic products. In addition, when the plastic product is an electronic device, electrostatic discharge not only causes damage to the electronic device, but also has a risk of causing a fire or explosion.

Antistatic materials are used to prevent the generation of static electricity in plastic products. By applying an antistatic coating agent, in which a conductive polymer is dispersed in a solvent, to a plastic product as an antistatic material, generation of static electricity is prevented. As such a conductive polymer, a π-conjugated conductive polymer such as polyaniline or polythiophene is often used.

On the other hand, even if the antistatic material is applied, the adverse effect due to static electricity can not be completely prevented. For example, in a low humidity environment, the human body is charged with electrostatic charges of several thousand volts or more. In such a state where static electricity is charged, if you touch an article with antistatic property, static electricity of high voltage of several thousand V or more is discharged at once, and the article with antistatic property is subjected to electric shock, The conductive polymer that has been subjected to the electric shock is oxidatively degraded. In addition, for example, when a sheet-like article having an antistatic property is in contact with another adherend, when it is attempted to peel the sheet-like article from the adherend, discharge occurs due to peeling, and the conductive polymer Is oxidatively degraded. The conductive polymer which has been oxidized and deteriorated has a problem that the antistatic property is lowered, and the effect of preventing adhesion of dust and removing static electricity is reduced. Therefore, in order to secure the antistatic property at a high level, it has been required to develop an antistatic material that is resistant to deterioration caused by electrostatic discharge.

Patent documents 1-2 mix | blends microparticles | fine-particles with the antistatic layer of a laminated body in order to improve anti-glare property, the slipperiness of a coating film, and blocking resistance. However, in Patent Document 1, as the antistatic agent, a cationic polymer is used, and in Patent Document 2, fine particles themselves are used, and the conductivity is low and the antistatic effect is not sufficient.

In patent document 3, microparticles | fine-particles are mix | blended in the surface protection film for optical films in order to improve anti-glare property. In Patent Document 4, a small amount of fine particles is blended as a lubricant of a coating film in an antistatic layer of a protective film for a polarizing plate containing a polythiophene-based conductive polymer. However, applications other than anti-glare properties and lubricants of microparticles have not been studied.

JP, 2008-020698, A Japanese Patent Application Publication No. 2008-087434 JP, 2011-191768, A Japanese Patent Laid-Open No. 2000-026817

An object of the present invention is to provide a laminate in which the antistatic performance is unlikely to deteriorate even when subjected to an electric shock due to static electricity.

The present inventors, in an antistatic layer consisting of a coating composition containing an organic conductive material and fine particles, have an antistatic performance even when subjected to electric shock due to static electricity when the average particle diameter of the fine particles is larger than the thickness of the antistatic layer. It has been found that the deterioration of the present invention can be suppressed and the laminate of the present invention is completed.

That is, the present invention is a laminate having an antistatic layer on at least one surface of a substrate film, wherein the antistatic layer comprises an organic conductive material (a) and fine particles having an average particle diameter of 10 to 500 nm. And a coating composition comprising 10 to 50% by weight of fine particles (b), the thickness A (nm) of the antistatic layer and the average particle size B (nm) of the fine particles (b) The present invention relates to a laminate wherein the relationship of 1) and 1 satisfies the relationship 1 <B / A.

It is preferable that the organic conductive material (a) is a conductive polymer and / or a carbon material.

The fine particles (b) are preferably inorganic fine particles and / or organic fine particles having a crosslinked structure.

It is preferable that the thickness A (nm) of the antistatic layer and the average particle size B (nm) of the fine particles (b) satisfy the relationship of 1.0 <B / A ≦ 3.3.

It is preferable that the haze value measured based on JISK7150 is 5% or less.

The adhesive layer is preferably disposed on the side of the substrate film not in contact with the antistatic layer.

Moreover, this invention relates to the surface protection film containing the said laminated body.

The laminate of the present invention can maintain the antistatic performance even when it receives a shock due to static electricity.

(1) Laminate The present invention is a laminate having an antistatic layer on at least one surface of a substrate film, wherein the antistatic layer comprises an organic conductive material (a) and an average particle diameter of 10 to 500 nm. Comprising 10 to 50% by weight of the fine particles (b), the thickness A (nm) of the antistatic layer and the average particle size of the fine particles (b) B (nm) satisfies the relationship of 1 <B / A.

The laminate of the present invention has an antistatic layer on at least one surface of a substrate film.

The material of the base film is, for example, glass, polyester resin such as polyethylene terephthalate (PET), polyethylene naphthalate, modified polyester, polyethylene (PE) resin, polypropylene (PP) resin, polystyrene resin, cyclic olefin resin, etc. Polyolefin resins, polyvinyl resins such as polyvinyl chloride and polyvinylidene chloride, polyetheretherketone (PEEK) resin, polysulfone (PSF) resin, polyethersulfone (PES) resin, polycarbonate (PC) resin, polyamide resin Polyimide resin, acrylic resin, triacetyl cellulose (TAC) resin and the like. These materials may be used alone or in combination of two or more.

The thickness of the substrate film is not particularly limited, but is preferably 10 to 10000 μm, and more preferably 25 to 5000 μm. The total light transmittance of the base film is preferably 60% or more, more preferably 70% or more, and still more preferably 80% or more.

The antistatic layer is made of a coating composition containing an organic conductive material and fine particles having an average particle diameter of 10 to 500 nm.

The organic conductive material contained in the coating composition is not particularly limited, but may be, for example, a conductive polymer, a carbon material, etc. because of its excellent conductivity and small humidity dependency. These organic conductive materials may be used alone or in combination of two or more.

The conductive polymer is not particularly limited, and conventionally known conductive polymers can be used. Specific examples thereof include, for example, polythiophene, polypyrrole, polyaniline, polyacetylene, polyphenylene vinylene, polynaphthalene, derivatives thereof, and derivatives thereof And complexes of these with a dopant. These conductive polymers may be used alone or in combination of two or more.

The conductive polymer is preferably a conductive polymer containing at least one thiophene ring in the molecule. The reason is that by containing a thiophene ring in the molecule, a molecule having high conductivity is easily formed.

The conductive polymer is more preferably poly (3,4-disubstituted thiophene) or a complex of poly (3,4-disubstituted thiophene) and polyanion. It is because it is extremely excellent in conductivity and chemical stability. In addition, when containing a complex of poly (3,4-disubstituted thiophene) or a poly (3,4-disubstituted thiophene) and a polyanion, it is possible to form the antistatic layer in a short time at a low temperature. It is possible to be excellent in productivity.

As poly (3,4-disubstituted thiophene), poly (3,4-dialkoxythiophene) or poly (3,4-alkylenedioxythiophene) is particularly preferable. As poly (3,4-dialkoxythiophene) or poly (3,4-alkylenedioxythiophene), the following formula (I):

Polythiophene in the cationic form consisting of repeating structural units shown in is preferred. Here, R ¹ and R ² independently represent a hydrogen atom or a C _1-4 alkyl group, or a C _1-4 alkylene group when R ¹ and R ² are bonded to each other Represents The C _1-4 alkyl group is not particularly limited, and examples thereof include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group and a t-butyl group. . In addition, when R ¹ and R ² are bonded, the C _1-4 alkylene group is not particularly limited, and examples thereof include a methylene group, a 1,2-ethylene group, a 1,3-propylene group, and 1,1, 4-butylene group, 1-methyl-1,2-ethylene group, 1-ethyl-1,2-ethylene group, 1-methyl-1,3-propylene group, 2-methyl-1,3-propylene group, etc. It can be mentioned. Among these, a methylene group, a 1,2-ethylene group and a 1,3-propylene group are preferable, and a 1,2-ethylene group is more preferable. The C _1-4 alkyl group and the C _1-4 alkylene group may have part of their hydrogens substituted. As the polythiophene having a C _1-4 alkylene group, poly (3,4-ethylenedioxythiophene) is particularly preferable.

The poly anion can form a complex by forming an ion pair with the polythiophene (derivative), and the polythiophene (derivative) can be stably dispersed in water. Examples of poly anions include, but are not limited to, carboxylic acid polymers (eg, polyacrylic acid, polymaleic acid, polymethacrylic acid, etc.), sulfonic acid polymers (eg, polystyrene sulfonic acid, polyvinyl sulfonic acid, polyisoprene) Sulfonic acid etc. etc. may be mentioned. These carboxylic acid polymers and sulfonic acid polymers are also copolymers of vinyl carboxylic acids and vinyl sulfonic acids with other polymerizable monomers, such as acrylates, aromatic vinyl compounds such as styrene, vinyl naphthalene and the like. It may be Among these, polystyrene sulfonic acid is particularly preferred.

The polystyrene sulfonic acid preferably has a weight average molecular weight of more than 20,000 and 500,000 or less, and more preferably 40,000 to 200,000. If polystyrene sulfonic acid whose molecular weight is out of this range is used, the dispersion stability to water of the polythiophene conductive polymer may be reduced. The weight average molecular weight is a value measured by gel permeation chromatography (GPC). A Waters ultrahydrogel 500 column was used for the measurement.

The conductive polymer is preferably a complex of poly (3,4-ethylenedioxythiophene) and polystyrene sulfonic acid because it is particularly excellent in transparency and conductivity.

The conductive polymer is a complex of poly (3,4-ethylenedioxythiophene) and polystyrene sulfonic acid, and more preferably has a conductivity of 0.01 S / cm or more. The reason is that a coating composition containing such a conductive polymer is particularly excellent in transparency and conductivity when used as a transparent conductive film.

The carbon material is not particularly limited, and examples thereof include carbon nanotubes, graphene, fullerene and the like. These carbon materials may be used alone or in combination of two or more.

The content of the organic conductive material in the coating composition is not particularly limited, but, for example, when a conductive polymer is used as the organic conductive material, it is 0.01 to 50.0 mg / m when used as an antistatic layer. ^An amount of ² is preferable, and an amount of 0.1 to 10.0 mg / m ² is more preferable. If it is less than 0.01 mg / m ² , the proportion of the conductive polymer in the antistatic layer may be small, and the conductivity of the antistatic layer may not be sufficiently ensured, while 50.0 mg / m 2. ^If it exceeds ² , the proportion of the conductive polymer in the antistatic layer increases, which may cause an adverse effect on the strength of the coating film and the film forming property. When a carbon material is used as the organic conductive material, an amount of 0.01 to 50.0 mg / m ² is preferable in the formation of the antistatic layer, and an amount of 0.1 to 10.0 mg / m ² is More preferable.

Coating compositions include binders, conductivity improvers, solvents, crosslinkers, catalysts, surfactants and / or leveling agents, water-soluble antioxidants, antifoams, rheology control agents, neutralizers, thickeners, etc. May be contained.

The binder is not particularly limited, but is preferably at least one selected from the group consisting of polyester resins, acrylic resins, polyurethanes, epoxy resins, alkoxysilane oligomers, polyolefin resins, and melamine resins. The reason is that the compatibility with components such as organic conductive materials is high, and the antistatic layer formed using a coating composition containing these binders has a good affinity to the substrate, and a defective film portion It is because it can be made invisible efficiently. Moreover, the antistatic layer formed using the coating composition containing these binders has favorable hardness and chemical resistance. These binders may be used alone or in combination of two or more.

The polyester resin is not particularly limited as long as it is a polymer compound obtained by polycondensation of a compound having two or more carboxyl groups in the molecule and a compound having two or more hydroxyl groups, for example, polyethylene Examples thereof include terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate. These may be used alone or in combination of two or more.

The acrylic resin is not particularly limited, and examples thereof include (meth) acrylic resins and vinyl ester resins. The acrylic resin may be, for example, a polymer containing a polymerizable monomer having an acid group such as a carboxyl group, an acid anhydride group, a sulfonic acid group or a phosphoric acid group as a constituent monomer, for example, an acid group And a copolymer of a polymerizable monomer having an acid group and a copolymer of a polymerizable monomer having an acid group and a copolymerizable monomer. These may be used alone or in combination of two or more.

The (meth) acrylic resin may be polymerized with a copolymerizable monomer as long as it contains a (meth) acrylic monomer as a main constituent monomer (for example, 50 mol% or more). In this case, At least one of the (meth) acrylic monomer and the copolymerizable monomer may have an acid group.

Examples of (meth) acrylic resins include (meth) acrylic monomers having an acid group [(meth) acrylic acid, sulfoalkyl (meth) acrylate, sulfonic acid group-containing (meth) acrylamide, etc.] Polymer, (meth) acrylic monomer optionally having acid group, and other polymerizable monomer having acid group [other polymerizable carboxylic acid, polymerizable polyvalent carboxylic acid or anhydride , Vinyl aromatic sulfonic acid, etc.] and / or copolymerizable monomers [eg, (meth) acrylic acid alkyl ester, glycidyl (meth) acrylate, (meth) acrylonitrile, aromatic vinyl monomer etc.] Polymer, other polymer monomer having an acid group and (meth) acrylic copolymerizable monomer [eg, (meth) acrylic acid alkyl ester, hydroxyalkyl (meth) acrylate, Rishijiru (meth) acrylate, copolymers of (meth) acrylonitrile, etc.], rosin-modified urethane acrylate, special modified acrylic resins, urethane acrylates, epoxy acrylates, and urethane acrylates emulsion and the like.

Among these (meth) acrylic resins, (meth) acrylic acid- (meth) acrylic acid ester polymers (acrylic acid-methyl methacrylate copolymer etc.), (meth) acrylic acid- (meth) acrylic acid Ester-styrene copolymer (acrylic acid-methyl methacrylate-styrene copolymer etc.) and the like are preferable.

The polyurethane is not particularly limited as long as it is a polymer compound obtained by copolymerizing a compound having an isocyanate group and a compound having a hydroxyl group, and, for example, ester / ether polyurethane, ether polyurethane, polyester polyurethane, A carbonate type polyurethane, an acrylic type polyurethane, etc. are mentioned. These may be used alone or in combination of two or more.

The epoxy resin is not particularly limited, but, for example, bisphenol A type, bisphenol F type, phenol novolak type, polyfunctional tetrakis (hydroxyphenyl) ethane type or tris (hydroxyphenyl) methane type having a large number of benzene rings And epoxy resins such as biphenyl type, triphenolmethane type, naphthalene type, ortho novolac type, dicyclopentadiene type, aminophenol type and alicyclic, silicone epoxy resin and the like. These may be used alone or in combination of two or more.

The alkoxysilane oligomer is, for example, a polymerized alkoxysilane formed by condensation of monomers of the alkoxysilane represented by the following formula (II), and is a siloxane bond (Si-O-Si) An oligomer etc. which have 1 or more in 1 molecule are mentioned.
SiR ₄ (II)
(Wherein R is hydrogen, a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, an alkyl group which may have a substituent, a phenyl group which may have a substituent, provided that four Rs are At least one of them is an alkoxy group having 1 to 4 carbon atoms or a hydroxyl group)

The structure of the alkoxysilane oligomer is not particularly limited, and may be linear or branched. Moreover, the alkoxysilane oligomer may use the compound represented by Formula (II) independently, and may use 2 or more types together. The weight average molecular weight of the alkoxysilane oligomer is not particularly limited, but is preferably more than 152 and 4000 or less, and more preferably 500 to 2,500. Here, the weight average molecular weight is a value measured by gel permeation chromatography (GPC).

The polyolefin resin is not particularly limited, and examples thereof include polyethylene, polypropylene, chlorinated polypropylene, maleic anhydride modified polypropylene, and maleic anhydride modified chlorinated polypropylene. These may be used alone or in combination of two or more.

When the coating composition contains a binder, the content thereof is not particularly limited, but is preferably 0.1 to 1000 parts by weight, and 5 to 500 parts by weight with respect to 100 parts by weight of the conductive material. It is more preferable that When the content of the binder is less than 0.1 parts by weight, the strength of the antistatic layer may be weakened, while when it exceeds 1000 parts by weight, the proportion of the conductive material in the antistatic layer is relatively small. In some cases, the conductivity of the antistatic layer can not be sufficiently secured.

When the coating composition contains a conductivity improver, the conductivity improver is not particularly limited, and examples thereof include amides such as N-methylformamide, N, N-dimethylformamide, γ-butyrolactone, N-methylpyrrolidone and the like. Compounds: ethylene glycol, diethylene glycol, propylene glycol, trimethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, catechol, cyclohexanediol, cyclohexanedimethanol, glycerin, Hydroxyl group-containing compounds such as diethylene glycol monoethyl ether, propylene glycol monomethyl ether; isophorone, propylene carbonate, cyclohexanone, acetylacetone, ethyl acetate, Ethyl Seto acetate, methyl orthoacetate, carbonyl-containing compounds such as ethyl orthoformate; compound having a sulfo group such as dimethyl sulfoxide and the like. These may be used alone or in combination of two or more.

The solvent is not particularly limited, and, for example, water; alcohols such as methanol, ethanol, 2-propanol and 1-propanol; ethylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol and tetraethylene glycol; ethylene glycol monomethyl Glycol ethers such as ether, diethylene glycol monomethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether; glycol ether acetates such as ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate; propylene glycol, dipropylene glycol, Such as tripropylene glycol Propylene glycol ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether; propylene glycol ether acetates such as propylene glycol monomethyl ether acetate; diethyl Ethers such as ether, diisopropyl ether, methyl-t-butyl ether and tetrahydrofuran; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; toluene, xylene (o-, m- or p-xylene), hexane, heptane Hydrocarbons such as: Esters such as ethyl acetate and butyl acetate: Androgenic compounds, acetonitrile, water and a mixed solvent of these organic solvents (water-containing organic solvent), a mixed solvent of two or more organic solvents. These solvents may be used alone or in combination of two or more.

The solvent preferably does not remain in the antistatic layer formed using the coating composition. In addition, in the present specification, the one that completely dissolves all the components of the coating composition (i.e., the "solvent") and the one that disperses the insoluble components (i.e., the "dispersion medium") are not distinguished. In both, it describes as a "solvent."

By blending the crosslinking agent, the thermosetting binder resin can be crosslinked, and the antistatic performance can be improved. Although it does not specifically limit as a crosslinking agent, For example, crosslinking agents, such as melamine type, polycarbodiimide type, polyoxazoline type, polyepoxy type, polyisocyanate type, polyacrylate type etc., are mentioned. These crosslinking agents may be used alone or in combination of two or more.

When the coating composition contains a crosslinking agent, its content is not particularly limited, but it is preferably 30% by weight or less in the coating composition, and more preferably 20% by weight or less.

When the coating composition contains a thermosetting binder resin and a crosslinking agent, the catalyst for crosslinking the thermosetting binder resin is not particularly limited, and examples thereof include a photopolymerization initiator and a thermal polymerization initiator. Be

By blending a surfactant and / or a leveling agent into the coating composition, the leveling property of the coating composition can be improved, and by using such a coating composition, a uniform antistatic layer can be formed. Can.

The surfactant is not particularly limited as long as it has a leveling property improving effect, and specific examples thereof include, for example, polyether-modified polydimethylsiloxane, polyether-modified siloxane, polyetherester-modified hydroxyl group-containing polydimethylsiloxane Siloxane compounds such as polyether-modified acrylic group-containing polydimethylsiloxane, polyester-modified acrylic group-containing polydimethylsiloxane, perfluoropolydimethylsiloxane, perfluoropolyether-modified polydimethylsiloxane, perfluoropolyester-modified polydimethylsiloxane, etc .; Fluorine compounds such as alkyl carboxylic acids; polyether compounds such as polyoxyethylene alkyl phenyl ether; carboxylic acids such as coconut oil fatty acid amine salt; phosphoric acid Ester compounds such as alkyl ether sulfates, sorbitan fatty acid esters, sulfonic acid esters, succinic acid esters, etc .; alkyl aryl sulfonic acid amine salts, sulfonic acid compounds such as dioctyl sodium sulfosuccinate; phosphates such as sodium lauryl phosphate Compounds; Amide compounds such as coconut oil fatty acid ethanolamide; Acrylic compounds etc. may be mentioned. These surfactants may be used alone or in combination of two or more. Among these, siloxane compounds and fluorine compounds are preferable because the leveling property improvement effect can be remarkably obtained.

The leveling agent is not particularly limited. For example, polyether-modified polydimethylsiloxane, polyether-modified siloxane, polyetherester-modified hydroxyl group-containing polydimethylsiloxane, polyether-modified acrylic group-containing polydimethylsiloxane, polyester-modified acrylic group-containing poly Siloxane-based compounds such as dimethylsiloxane, perfluoropolydimethylsiloxane, perfluoropolyether-modified polydimethylsiloxane, perfluoropolyester-modified polydimethylsiloxane, and the like; fluorine-based compounds such as perfluoroalkylcarboxylic acid and perfluoroalkylpolyoxyethylene ethanol; Polyether-based compounds such as polyoxyethylene alkyl phenyl ether, propylene oxide polymer, ethylene oxide polymer, etc .; coconut oil Fatty acid amine salts, carboxylic acids such as gum rosin; castor oil sulfuric acid esters, phosphoric acid esters, alkyl ether sulfates, sorbitan fatty acid esters, sulfonic acid esters, esters such as succinic acid esters; alkyl aryl sulfonic acid amine salts, Sulfonate compounds such as dioctyl sodium sulfosuccinate; Phosphate compounds such as sodium lauryl phosphate; Amide compounds such as coconut oil fatty acid ethanolamide; Acrylic compounds and the like. These leveling agents may be used alone or in combination of two or more. Among these leveling agents, siloxane compounds and fluorine compounds are preferable because they are excellent in dispersion stability when formulated into a conductive coating composition.

When the coating composition contains a surfactant and / or a leveling agent, the content thereof is not particularly limited, but is preferably 1 to 20% by weight, more preferably 5 to 10% by weight in the coating composition.

By blending a water-soluble antioxidant with the coating composition, the heat resistance and the moist heat resistance of the antistatic layer can be improved. The water-soluble antioxidant is not particularly limited, and examples thereof include reducing water-soluble antioxidants and non-reducing water-soluble antioxidants.

When the coating composition contains a water-soluble antioxidant, the content thereof is not particularly limited, but is preferably 1 to 20% by weight, and more preferably 5 to 10% by weight in the coating composition.

The fine particles contained in the coating composition are not particularly limited, and examples thereof include inorganic fine particles and organic fine particles having a crosslinked structure. The inorganic fine particles are not particularly limited, but, for example, silica fine particles such as colloidal silica, hollow silica, fumed silica, and metal oxide fine particles such as titania, zirconia, etc., and thermoplastic or thermosetting acrylic resin coated with silica Core-shell type acrylic-silica composite particles, Core-shell type melamine-silica composite particles in which melamine resin is coated with silica, Core-shell type acrylic-silica composite particles in which silica particles are coated with thermoplastic or thermosetting acrylic resin, Silica Examples thereof include core-shell type melamine-silica composite particles in which particles are coated with a melamine resin, organic-inorganic composite particles such as acrylic-silica composite particles in which small silica fine particles are supported by thermoplastic or thermosetting acrylic fine particles. The organic particles are not particularly limited, and examples thereof include fluorine resin particles, acrylic resin particles, melamine resin particles, and urethane rubber particles. These fine particles may be used alone or in combination of two or more. By containing these fine particles, the concentration of the organic conductive material in the antistatic layer locally increases, and it is considered that the voltage resistance can be improved.

The average particle diameter of the fine particles is not particularly limited as long as it is 10 to 500 nm, but 20 to 200 nm is preferable, and 50 to 150 nm is more preferable. When the average particle size is less than 10 nm, it is difficult to form an antistatic layer having a thickness smaller than the particle size, and the particles can not be exposed on the surface of the antistatic layer. The antistatic performance tends to deteriorate. When it exceeds 500 nm, most of the fine particles are exposed on the surface of the antistatic layer, and the particles tend to fall off and the haze of the antistatic layer tends to rise.

The volume resistivity of the fine particles is not particularly limited, but is preferably 10 ² Ω · cm or more, more preferably 10 ⁴ Ω · cm or more, and still more preferably 10 ⁶ Ω · cm or more.

The thickness A (nm) of the antistatic layer and the average particle size B (nm) of the fine particles (b) satisfy the relationship of 1 <B / A. By satisfying this relationship, a part of the fine particles is exposed on the surface of the antistatic layer to prevent the static electricity generation source from coming into direct contact with the antistatic layer, and charging is prevented even if the laminate is subject to electrostatic discharge. Performance degradation can be suppressed. Although B / A satisfies the relationship of 1 <B / A, it is preferable that 1.0 <B / A ≦ 3.3, and it is more preferable that 2.1 <B / A ≦ 3. When B / A is 1 or less, the particles can not be exposed on the surface of the antistatic layer, and the resistance of the laminate to electrostatic discharge tends to decrease.

The thickness A (nm) of the antistatic layer is preferably 5 ≦ A ≦ 200, more preferably 10 ≦ A ≦ 100, and still more preferably 30 ≦ A ≦ 50.

The content of the fine particles in the coating composition is not particularly limited as long as it is 10 to 50% by weight, but 10 to 30% by weight is preferable, and 15 to 25% by weight is more preferable. If the content is less than 10% by weight, the organic conductive material tends to be susceptible to the impact of static electricity, and the antistatic performance tends to deteriorate. When the content exceeds 50% by weight, the amount of fine particles in the antistatic layer is excessive and the portion exposed on the surface is increased, so that the particles tend to fall off or the haze of the antistatic layer is increased.

The substrate film may have an adhesive layer in addition to the antistatic layer. The adhesive layer is preferably disposed on the side of the substrate film not in contact with the antistatic layer. The adhesive layer is formed using an adhesive composition containing an adhesive. The pressure-sensitive adhesive is not particularly limited, and conventionally known ones can be used. Specifically, for example, (meth) obtained by homopolymerizing or copolymerizing various (meth) acrylic acid ester monomers Acrylic resin, ethylene / vinyl acetate copolymer resin, silicone resin such as silicone rubber having dimethylsiloxane skeleton, polyurethane resin obtained by polyaddition of polyol and polyisocyanate, natural rubber, styrene-isoprene-styrene block Copolymer (SIS block copolymer), styrene-butadiene-styrene block copolymer (SBS block copolymer), styrene-ethylene.butylene-styrene block copolymer (SEBS block copolymer), styrene-butadiene Rubber, Polybutadiene, Polyisoprene, Polyisob Ren, butyl rubber, rubber-based resins such as chloroprene rubber. Among these, (meth) acrylic resins, silicone resins, and polyurethane resins, which are excellent in chemical stability, have a high degree of freedom in chemical structure design, and can be easily adjusted in adhesive force, are preferable. Furthermore, (meth) acrylic resins and polyurethane resins are particularly preferable in that they are excellent in transparency.

The pressure-sensitive adhesive layer can be formed by a conventionally known method, for example, a method of applying a pressure-sensitive adhesive composition containing a pressure-sensitive adhesive to a glass substrate, crosslinking or heat-drying, crosslinking or heat-drying The method etc. which transcribe | transfer the adhesive layer to a glass base material are mentioned. The pressure-sensitive adhesive composition may contain a crosslinking agent in addition to the pressure-sensitive adhesive.

As a method of applying the pressure-sensitive adhesive composition, conventionally known methods can be used. Specifically, for example, roll coating method, gravure coating method, reverse coating method, roll brush method, spray coating method, air A knife coat method or the like can be used.

(2) Method of Forming Antistatic Layer The antistatic layer is formed by applying a coating composition containing an organic conductive material on at least one surface of a substrate film. The antistatic layer may be formed by applying the coating composition directly to the substrate film, or after applying another layer such as a primer layer on the substrate in advance, it is applied onto the layer. You may form.

The antistatic layer can be obtained by applying a coating composition on at least one surface of a substrate film and then heat treating it. The method for applying the coating composition to at least one surface of the substrate film is not particularly limited, and any known method can be used. For example, roll coating, bar coating, dip coating, spin coating, casting Method, die coat method, blade coat method, bar coat method, gravure coat method, curtain coat method, spray coat method, doctor coat method, slit coat method, letterpress printing method, stencil printing method, lithography (offset) A printing method, an intaglio (gravure) printing method, a spray printing method, an ink jet printing method, a tampon printing method, etc. can be used.

Before applying the coating composition on at least one side of the substrate film, the surface of the substrate film may be subjected to a surface treatment, if necessary. Examples of the surface treatment include corona treatment, plasma treatment, itro treatment, flame treatment and the like.

The heat treatment for forming the antistatic layer is not particularly limited and may be performed by a known method. For example, the heat treatment may be performed using a blowing oven, an infrared oven, a vacuum oven, or the like. When the coating composition contains a solvent, the solvent is removed by heat treatment.

The temperature condition of the heat treatment at the time of forming the antistatic layer is not particularly limited, but is preferably 150 ° C. or less, more preferably 50 to 140 ° C., and still more preferably 60 to 130 ° C. . If the temperature of the heat treatment exceeds 150 ° C., the material of the base used is limited, and it is not possible to use a base generally used for a transparent electrode film, such as a PET film polycarbonate film or an acrylic film. Although the processing time of heat processing is not specifically limited, It is preferable that it is 0.1 to 60 minutes, and it is more preferable that it is 0.5 to 30 minutes.

The surface resistivity of the antistatic layer is not particularly limited, but is preferably 10 ⁶ to 10 ¹⁰ Ω / □, and more preferably 10 ⁷ to 10 ⁹ Ω / □.

The refractive index of the antistatic layer is not particularly limited, but is preferably 1.4 to 1.7, and more preferably 1.5 to 1.6.

The haze value of the laminate of the present invention is not particularly limited, but is preferably 5% or less, more preferably 3% or less, and still more preferably 2% or less. When the haze value exceeds 5%, the transparency of the laminate may be deteriorated. In addition, since it is so preferable that the haze value is as small as possible, the lower limit is not particularly limited, and is, for example, 0.01%. The haze value in the present invention is measured in accordance with JIS K 7150.

(3) Surface Protective Film The laminate of the present invention can be suitably used for a surface protective film. The surface protective film is a film for protecting an optical film such as a polarizing plate and a light guide plate from scratches and dirt. For example, in the manufacture of liquid crystal panels, optical components (films) such as a polarizing plate and a light guide plate are laminated and assembled with the protective film attached, and the protective film is attached also in the inspection process. It is done as it is, and then it will eventually be peeled off and discarded. When used for a surface protective film, the laminate preferably has an adhesive layer.

The adhesion of the surface protective film varies depending on the adherend, but for example, when the adherend is a glass substrate such as non-alkali glass, the adhesion is 0.05 to 10 N / It is preferable that it is 25 mm.

In the surface protective film, a release paper (separator) may be attached to the surface of the adhesive layer, if necessary. The material of the release paper may be, for example, paper or a plastic film, but a plastic film is preferably used because it is excellent in surface smoothness. Examples of plastic films include polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, vinyl chloride copolymer films, polyethylene terephthalate films, polybutylene terephthalate films, polyurethane films, ethylene- A vinyl acetate copolymer film etc. are mentioned.

The release paper may be subjected to release agent treatment with a release agent such as silicone type, fluorine type, long chain alkyl type, fatty acid amide type, silica powder or the like on the surface in contact with the adhesive layer.

The surface protective film can be suitably used as a surface protective film of, for example, a liquid crystal panel, an organic EL display, a plasma display, a polarizing plate, a light diffusion sheet, a lens film, etc. These adherends can be mechanically and electrically Can be protected.

The laminate of the present invention can be suitably used not only for a surface protective film but also for a polarizing plate, a masking tape, a removable label and the like.

EXAMPLES Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to the following examples. Hereinafter, “%” means “% by weight” unless otherwise specified.

1. Materials used 1-1. Base film, PET film (Toray Industries, Inc., Lumilar T60)
1-2. Organic conductive material, conductive polymer PEDOT / PSS (made in Production Example 1, solid content 1.3%)
・ Carbon nanotube (made in Production Example 2, solid content ratio 1.1%)
1-3. Fine particle / silica fine particle (Nippon Shokuhin Co., Ltd. make, Sea Hoster KE-W10, average particle diameter 100 nm)
· Silica fine particles-acrylic resin emulsion (manufactured by DIC Corporation, DV-961, average particle diameter 150 nm)
・ Silica fine particles (Nissan Chemical Industries, Ltd., ST-XL, average particle size 50 nm)
・ Acrylic resin fine particles (manufactured by Nippon Shokubai Co., Ltd., Eposter MX 050 W, average particle diameter 70 nm)
1-4. Binder resin · Acrylic resin (made by Toagosei Co., Ltd., Julimer FC-80, solid content 30%, glass transition temperature 50 ° C)
Polyurethane (Superflex 830 HS, solid content 35%, glass transition temperature 68 ° C., manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
・ Polyester (manufactured by Toagosei Co., Ltd., Aronmelt PES-2405A30, solid content 30%, glass transition temperature 40 ° C.)
Melamine (manufactured by DIC Corporation, Beckamine M-3, solid content 77%)
Urethane acrylate (made by Daicel Ornex Co., Ltd., UCECOAT7655, solid content 35%)
1-5. Surfactant / silicone surfactant (Shin-Etsu Chemical Co., Ltd., X-22-4952)
・ Fluorinated surfactant (manufactured by DuPont, CAPSTONE FS-3100)
-Ether surfactant (manufactured by Clariant, Emulsogen LCN 070) 1-6. Antioxidant, L (+)-Ascorbic acid (manufactured by Wako Pure Chemical Industries, Ltd.)
· Gallic acid (manufactured by Wako Pure Chemical Industries, Ltd.)

2. Evaluation method 2-1. The surface resistivity of the surface resistivity laminate was measured using a resistivity meter (Hiresta UP (MCP-HT450 type) manufactured by Mitsubishi Chemical Corporation) and a URS probe. The probe was pressed against the antistatic layer, and the surface resistivity when maintained at an applied voltage of 10 V for 10 seconds was determined (SR1). Next, the probe was pressed against the antistatic layer, and the surface resistivity when maintained at an applied voltage of 1000 V for 60 seconds was determined (SR2). Then, a value (SR2 / SR1) obtained by dividing SR2 by SR1 was obtained as the surface resistance change rate. The surface resistance change rate indicates how much the antistatic performance changes due to the electric shock.

2-2. The haze immediately after the production of the haze laminate was measured using a haze computer (HGM-2B, manufactured by Suga Test Instruments Co., Ltd.) according to JIS K7150.

Production Example 1 Preparation of PEDOT: PSS water dispersion 92.3 parts of an aqueous solution of polystyrene sulfonic acid (VERSA-TL 72, manufactured by Akzo Nobel) and 3,4-ethylene using a 2000 ml three-necked glass flask equipped with a cooling pipe 7.1 parts of dioxythiophene (EDOT) was added to 1000 parts of ion-exchanged water to obtain a mixed solution. While stirring this mixture, a solution of 4.0 parts of ferric sulfate and 14.8 parts of ammonium peroxodisulfate in 100 parts of ion-exchanged water is added, and the mixture is stirred at 20 ° C. for 24 hours for oxidative polymerization. Did. Subsequently, 15 wt% of a cation exchange resin (Amberlite IR 120 B, manufactured by Organo Corporation) and an anion exchange resin (Amberlite IRA 67, manufactured by Organo Corporation) were added, and the mixture was further stirred for 18 hours. The obtained reaction mixture was filtered with a glass filter, and then homogenized by using a high-pressure homogenizer at 100 MPa for 10 times to obtain a PEDOT: PSS aqueous dispersion having a solid content of 1.3%.

Production Example 2 Preparation of Carbon Nanotube Water Dispersion One part by weight of carbon nanotube having an average length of 300 μm and a diameter of about 4 nm (Zeon Nano Technology Co., Ltd., ZEONANO SG101), sodium dodecylbenzene sulfonate as a dispersing agent (Wako Pure Chemical Industries, Ltd. 10 parts by weight of Co., Ltd.) and 989 parts by weight of pure water in a glass beaker and subjected to dispersion treatment with an ultrasonic homogenizer at 40 W for 30 minutes, and then the undispersed carbon nanotubes are removed by a centrifuge at 3500 rpm Thus, a carbon nanotube aqueous dispersion having a solid content of 1.1% was obtained.

(Examples 1 to 12, Comparative Example 1)
Each component was mixed in the weight ratio described in Table 1 to prepare a coating composition. The coating composition was applied to one side of the substrate film by bar coating. The antistatic layer was formed by drying at 120 ° C. for 2 minutes using a blower dryer to obtain a laminate. The film thickness of the antistatic layer was adjusted to the film thickness described in Table 1 by appropriately selecting the solid content of the coating composition and the number of the bar coater. Here, after the thing containing a photocurable binder (urethane acrylate) dried at 120 degreeC for 2 minutes, 500 mJ / cm < ² > ultraviolet irradiation was performed using the metal halide lamp, and it was made to harden | cure.

The surface resistivity and the haze of the laminates obtained in Examples 1 to 12 and Comparative Example 1 were evaluated by the method described above, and the particle size / film thickness and the SR change rate were calculated. The results are shown in Table 1. In the laminate of Comparative Example 1 which does not contain fine particles, the organic conductive material was deteriorated by the electric shock, the surface resistance change rate increased to about 2800 times, and the antistatic performance could not be maintained. The laminates of Examples 1 to 12 had the surface resistance change rate suppressed to at most about 240 times even after the electric shock, and the conductivity was maintained.

Claims (7)

A laminate having an antistatic layer on at least one surface of a substrate film,
The antistatic layer comprises a coating composition containing an organic conductive material (a) and fine particles (b) having an average particle diameter of 10 to 500 nm,
The coating composition contains 10 to 50% by weight of fine particles (b),
A laminate wherein the thickness A (nm) of the antistatic layer and the average particle diameter B (nm) of the fine particles (b) satisfy the relationship of 1 <B / A. The laminate according to claim 1, wherein the organic conductive material (a) is a conductive polymer and / or a carbon material. The laminate according to claim 1 or 2, wherein the fine particles (b) are inorganic fine particles and / or organic fine particles having a crosslinked structure. The thickness A (nm) of the antistatic layer and the average particle diameter B (nm) of the fine particles (b) satisfy the relationship of 1.0 <B / A ≦ 3.3. The laminated body as described in. The laminated body of any one of Claims 1-4 whose haze value measured based on JISK7150 is 5% or less. The laminated body of any one of Claims 1-5 by which the adhesion layer is arrange | positioned in the surface which does not contact with the antistatic layer of a base film. The surface protection film containing the laminated body of any one of Claims 1-6.