阅读说明：本技术 层积体 (Laminate body ) 是由 久留岛康功 枡谷勇太 于 2020-04-15 设计创作，主要内容包括：本发明涉及一种层积体,其是在热塑性树脂基材上依次层积有导电层和粘合层的导电层积体,其在维持层积体的导电性的同时,提高导电层与粘合层的密合性。一种导电层积体,其为在热塑性树脂基材(A)上依次层积有导电层(B)和粘合层(C)的导电层积体,其中,导电层(B)由包含导电性颗粒(b1)和树脂颗粒(b2)的导电性组合物构成,导电层(B)的与粘合层(C)接触的面的扩展面积比Sdr为0.001～0.3。(The present invention relates to a laminate in which a conductive layer and an adhesive layer are sequentially laminated on a thermoplastic resin substrate, and which has improved adhesion between the conductive layer and the adhesive layer while maintaining the conductivity of the laminate. A conductive laminate comprising a thermoplastic resin substrate (A) and, laminated in this order, a conductive layer (B) and an adhesive layer (C), wherein the conductive layer (B) is composed of a conductive composition comprising conductive particles (B1) and resin particles (B2), and the conductive layer (B) has an area ratio Sdr of 0.001 to 0.3 in extension of the surface thereof in contact with the adhesive layer (C).)

1. A conductive laminate comprising a thermoplastic resin substrate (A) and a conductive layer (B) and an adhesive layer (C) laminated in this order,

the conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2),

the spread area ratio Sdr of the surface of the conductive layer (B) in contact with the adhesive layer (C) is 0.001 to 0.3.

2. The conductive laminate as claimed in claim 1, wherein the ratio of the average particle diameter of the resin particles (b2) to the average particle diameter of the conductive particles (b1) is 0.1 to 100.

3. A conductive laminate comprising a thermoplastic resin substrate (A) and a conductive layer (B) and an adhesive layer (C) laminated in this order,

the conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2),

the average particle diameter of the resin particles (B2) is 0.2 to 15 times the film thickness of the conductive layer (B).

4. The conductive laminate as claimed in claim 3, wherein the conductive particles (B1) and the resin particles (B2) contained in the conductive composition have an average particle diameter of 0.3 to 20 times the thickness of the conductive layer (B).

5. The conductive laminate as claimed in any one of claims 1 to 4, wherein the amount of the resin particles (b2) mixed in the conductive composition is 10 to 5000 parts by weight based on 100 parts by weight of the conductive particles (b 1).

6. The conductive laminate as claimed in any one of claims 1 to 5, wherein the conductive particles (b1) are composed of 1 or more materials selected from the group consisting of polythiophene, polypyrrole, polyaniline and carbon nanomaterial.

7. The conductive laminate as claimed in any one of claims 1 to 6, wherein the resin particles (b2) are composed of 1 or more materials selected from the group consisting of polyolefin resins, polyurethane resins, acrylic resins and polyester resins.

8. The conductive laminate as claimed in any one of claims 1 to 7, wherein the adhesive layer (C) is composed of 1 or more materials selected from the group consisting of acrylic resins and urethane resins.

9. The method for producing the conductive laminate as claimed in any one of claims 1 to 8, which comprises the following steps (1) and (2):

(1) a step of forming a conductive layer (B) by applying a conductive composition (B) containing conductive particles (B1) and resin particles (B2) onto a thermoplastic resin substrate (a); and

(2) and a step of laminating the adhesive layer (C) on the surface of the conductive layer (B) by a transfer method.

10. The method for producing a conductive laminate according to claim 9, wherein in the step (1), the applied conductive composition (b) is heated at 40 to 110 ℃ for 0.5 to 5 minutes.

11. A conductive composition for forming a conductive layer (B) in the conductive laminate according to any one of claims 1 to 8, comprising conductive particles (B1) and resin particles (B2).

12. An optical member comprising the conductive laminate according to any one of claims 1 to 8.

Technical Field

The present invention relates to a conductive laminate. More particularly, the present invention relates to a conductive laminate having high adhesion between a conductive layer and an adhesive layer while maintaining conductivity.

Background

Various optical films and optical filters used in liquid crystal display devices and the like are required to have excellent optical characteristics, as well as characteristics such as adhesion and antistatic properties of the laminate. For example, in the case of a liquid crystal display device, polarizing plates are disposed on both sides of a liquid crystal cell, and light of only a polarized light component in a specific direction out of light irradiated from a light source and transmitted through a liquid crystal layer is emitted as display light. In a liquid crystal display device, it is necessary to stabilize the liquid crystal alignment to prevent image disturbance. Therefore, in order to prevent disturbance of electrolysis in the liquid crystal cell, the polarizing plate is required to have antistatic properties.

In the basic structure of the polarizing plate, transparent films are laminated from both sides to protect the polarizing element. Further, although the polarizing plate is fixed to the liquid crystal cell by the adhesive layer provided on the transparent film, the adhesive property between the transparent film and the adhesive layer is low, and therefore an anchor layer having adhesive property may be provided for both of them. If an ionic liquid is added to the pressure-sensitive adhesive layer, antistatic properties can be imparted to the polarizing plate, but the adhesion between the transparent film and the pressure-sensitive adhesive layer tends to be adversely affected, and stable adhesion cannot be secured. In patent document 1, conductive particles are added to the adhesive layer, but the adhesive force may be reduced by the addition of the particles.

Disclosure of Invention

Problems to be solved by the invention

The purpose of the present invention is to provide a conductive layer laminate in which a conductive layer and an adhesive layer are sequentially laminated on a thermoplastic resin substrate, wherein the adhesion between the conductive layer and the adhesive layer is improved while the conductivity of the laminate is maintained.

Means for solving the problems

The present inventors have found that, in a conductive laminate in which a conductive layer and an adhesive layer are sequentially laminated on a thermoplastic resin substrate, when the conductive layer is formed from a conductive composition containing conductive particles and resin particles and the surface of the conductive layer on the side in contact with the adhesive layer has a specific property, and/or when the average particle diameter of the resin particles is 0.2 to 15 times the film thickness of the conductive layer, the adhesion between the conductive layer and the adhesive layer can be improved while maintaining the conductivity of the laminate, and thus have completed the present invention.

That is, the present invention relates to a conductive laminate comprising a thermoplastic resin substrate (A) and a conductive layer (B) and an adhesive layer (C) laminated in this order,

the conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2),

the spread area ratio Sdr of the surface of the conductive layer (B) in contact with the adhesive layer (C) is 0.001 to 0.3.

The ratio of the average particle diameter of the resin particles (b2) to the average particle diameter of the conductive particles (b1) is preferably 0.1 to 100.

The present invention also relates to a conductive laminate comprising a thermoplastic resin substrate (A) and a conductive layer (B) and an adhesive layer (C) laminated in this order,

the conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2),

the average particle diameter of the resin particles (B2) is 0.2 to 15 times the film thickness of the conductive layer (B).

The average particle diameter of the conductive particles (B1) and the resin particles (B2) contained in the conductive composition is preferably 0.3 to 20 times the film thickness of the conductive layer (B).

In the conductive composition, the amount of the resin particles (b2) is preferably 10 to 5000 parts by weight based on 100 parts by weight of the conductive particles (b 1).

The conductive particles (b1) are preferably composed of 1 or more materials selected from the group consisting of polythiophene, polypyrrole, polyaniline, and carbon nanomaterial.

The resin particles (b2) are preferably composed of 1 or more materials selected from the group consisting of polyolefin resins, polyurethane resins, acrylic resins, and polyester resins.

The adhesive layer (C) is preferably composed of 1 or more materials selected from the group consisting of acrylic resins and urethane resins.

The present invention also relates to a method for producing the conductive laminate, including the following steps (1) and (2):

(1) a step of forming a conductive layer (B) by applying a conductive composition (B) containing conductive particles (B1) and resin particles (B2) onto a thermoplastic resin substrate (a); and

(2) and a step of laminating the adhesive layer (C) on the surface of the conductive layer (B) by a transfer method.

In the step (1), the conductive composition (b) to be applied is preferably heated at 40 to 110 ℃ for 0.5 to 5 minutes.

The present invention also relates to a conductive composition for forming a conductive layer (B) in the above conductive laminate, the conductive composition comprising conductive particles (B1) and resin particles (B2).

The present invention also relates to an optical member comprising the above conductive laminate.

ADVANTAGEOUS EFFECTS OF INVENTION

The laminate of the present invention is a conductive laminate in which a conductive layer and an adhesive layer are sequentially laminated on a thermoplastic resin substrate, and has high adhesion between the conductive layer and the adhesive layer while maintaining the conductivity of the laminate.

Detailed Description

< conductive laminate >

The conductive laminate of the invention according to claim 1 is a conductive laminate in which a conductive layer (B) and an adhesive layer (C) are sequentially laminated on a thermoplastic resin substrate (a), wherein the conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2), and the spread area ratio Sdr of the surface of the conductive layer (B) in contact with the adhesive layer (C) is 0.001 to 0.3.

The conductive laminate of the invention according to the 2 nd aspect is a conductive laminate in which a conductive layer (B) and an adhesive layer (C) are sequentially laminated on a thermoplastic resin substrate (a), characterized in that the conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2), and the average particle diameter of the resin particles (B2) is 0.2 to 15 times the film thickness of the conductive layer (B).

< thermoplastic resin base Material (A) >

Examples of the material of the thermoplastic resin substrate (a) include polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate, and modified polyester, polyolefin resins such as Polyethylene (PE) resin, polypropylene (PP) resin, polystyrene resin, and cycloolefin resin, vinyl resins such as polyvinyl chloride and polyvinylidene chloride, polyether ether ketone (PEEK) resin, Polysulfone (PSF) resin, Polyether Sulfone (PEs) resin, Polycarbonate (PC) resin, polyamide resin, polyimide resin, acrylic resin, and triacetyl cellulose (TAC) resin. These materials may be used alone or in combination of two or more.

The thickness of the thermoplastic resin base (A) is not particularly limited, but is preferably 10 to 10000. mu.m, more preferably 25 to 5000. mu.m. The total light transmittance of the thermoplastic resin substrate is preferably 60% or more, more preferably 70% or more, and further preferably 80% or more.

< conductive composition >

The conductive layer (B) is composed of a conductive composition containing conductive particles (B1) and resin particles (B2).

< conductive particles (b1) >

The conductive particles (b1) are not particularly limited, and include, for example, conductive polymers and carbon materials because they have excellent conductivity and small humidity dependence. These conductive particles (b1) may be used alone, or two or more of them may be used in combination.

The conductive polymer is not particularly limited, and conventionally known conductive polymers can be used, and specific examples thereof include polythiophene, polypyrrole, polyaniline, polyacetylene, polyphenylacetylene, polynaphthalene, derivatives thereof, and complexes thereof with a dopant. These conductive polymers may be used alone, or two or more kinds thereof may be used in combination.

The conductive polymer is preferably a conductive polymer containing at least 1 thiophene ring in the molecule. The reason for this is that a molecule having high conductivity is easily formed by including a thiophene ring in the molecule.

More preferably, the conductive polymer is poly (3, 4-disubstituted thiophene) or a complex of poly (3, 4-disubstituted thiophene) and a polyanion. This is because the conductivity and chemical stability are extremely excellent. In addition, when the polymer contains poly (3, 4-disubstituted thiophene) or a complex of poly (3, 4-disubstituted thiophene) and a polyanion, an antistatic layer can be formed at a low temperature in a short time, and productivity is also excellent.

As the 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), there is preferably used a compound represented by the following formula (I):

[ solution 1]

The structural unit shown in the figure constitutes the polythiophene in a cation form. Here, R¹And R²Independently of one another, represents a hydrogen atom or C_1-4Or at R¹And R²In the case of bonding, represents C_1-4An alkylene group of (a). As C_1-4The alkyl group (b) 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 tert-butyl group. In addition, in R¹And R²In the case of bonding, as C_1-4The alkylene group (b) is not particularly limited, and examples thereof include a methylene group, a 1, 2-ethylene group, a 1, 3-propylene group, a 1, 4-butylene group, a 1-methyl-1, 2-ethylene group, a 1-ethyl-1, 2-ethylene group, a 1-methyl-1, 3-propylene group, and a 2-methyl-1, 3-propylene group. Among these, methylene, 1, 2-ethylene and 1, 3-propylene are preferable, and 1, 2-ethylene is more preferable. C_1-4Alkyl and C_1-4A part of hydrogen of the alkylene group of (a) may be substituted. As having C_1-4The polythiophene of (4) is particularly preferably poly (3, 4-ethylenedioxythiophene).

The polyanion forms a complex by forming an ion pair with the polythiophene (derivative), and can stably disperse the polythiophene (derivative) in water. The polyanion is not particularly limited, and examples thereof include carboxylic acid polymers (e.g., polyacrylic acid, polymaleic acid, polymethacrylic acid, etc.), sulfonic acid polymers (e.g., polystyrenesulfonic acid, polyvinylsulfonic acid, polyisoprene sulfonic acid, etc.), and the like. The carboxylic acid polymers and sulfonic acid polymers may be copolymers of vinyl carboxylic acids and vinyl sulfonic acids with other polymerizable monomers, for example, aromatic vinyl compounds such as acrylates, styrene, and vinyl naphthalene. Among these, polystyrene sulfonic acid is particularly preferable.

The polystyrene sulfonic acid has a weight average molecular weight of more than 20000, preferably 500000 or less, and more preferably 40000 to 200000. When polystyrenesulfonic acid having a molecular weight outside this range is used, the dispersion stability of the polythiophene-based conductive polymer with respect to water may be lowered. The weight average molecular weight is a value measured by Gel Permeation Chromatography (GPC). For the measurement, an ultrahydrogel500 column manufactured by Waters corporation was used.

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

The conductive polymer is more preferably a composite of poly (3, 4-ethylenedioxythiophene) and polystyrene sulfonic acid, and has an electrical conductivity of 0.01S/cm or more. The reason for this is that a conductive layer formed from a conductive composition containing such conductive particles is particularly excellent in transparency and conductivity.

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

The conductive particles (b1) preferably have an average particle diameter of 5 to 1000nm, more preferably 10 to 800nm, and still more preferably 20 to 600 nm. When the amount is within the above range, the resulting resin composition tends to have excellent conductivity, dispersion stability and transparency. The average particle diameter in the present invention is a particle diameter at 50% of the cumulative volume as measured by the dynamic light scattering method (D50), and can be measured by the method described in examples.

The content of the conductive particles (b1) in the conductive composition is not particularly limited, and is preferably 0.1 to 80 parts by weight, more preferably 1 to 60 parts by weight, and further preferably 3 to 55 parts by weight, based on 100 parts by weight of the total solid content of the conductive composition. When the amount is within the above range, the conductivity can be sufficiently ensured, and the strength and film forming property of the coating film can be ensured.

In addition, as for the content of the conductive particles (b1) in the conductive composition, a conductive polymer is usedIn the case of the conductive particles (B1), the content of the conductive layer (B) is preferably 0.01 to 50.0mg/m²More preferably 0.1 to 10.0mg/m²The amount of (c). This is because, at less than 0.01mg/m²In the case of this, the proportion of the conductive particles (B1) in the conductive layer (B) decreases, and the conductivity of the conductive layer (B) may not be sufficiently ensured; on the other hand, if it exceeds 50.0mg/m²The presence ratio of the conductive particles (B1) in the conductive layer (B) increases, and the strength and film forming property of the coating film may be adversely affected. When a carbon material is used as the conductive particles (B1), it is preferable that the amount of the conductive layer (B) is 0.01 to 50.0mg/m²More preferably 0.1 to 10.0mg/m²The amount of (c).

< resin particles (b2) >

The material of the resin particles (b2) is not particularly limited, and is preferably at least one selected from the group consisting of polyolefin resins, polyurethane resins, acrylic resins, polyester resins, epoxy resins, polysiloxanes, and melamine resins. The reason for this is that the compatibility with the conductive particles (B1) is high, and the conductive layer (B) formed using the conductive composition containing these resin particles (B2) has good affinity for the thermoplastic resin substrate (a). In order to cause physical interaction with the conductive particles (b1) in the conductive composition, the resin particles (b2) are preferably insoluble in a solvent to be described later, and more preferably insoluble in water. The surface of the conductive layer (B) formed using the conductive composition containing these resin particles (B2) has an uneven shape, and has good adhesion to the adhesive layer (C). These resin particles (b2) may be used alone or in combination of two or more.

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.

The urethane resin 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 examples thereof include ester/ether polyurethanes, polyester polyurethanes, carbonate polyurethanes, and acrylic polyurethanes. 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 any polymer as long as it contains, as a constituent monomer, 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, and examples thereof include a homopolymer or 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 contain a (meth) acrylic monomer as a main constituent monomer (for example, 50 mol% or more), and may be polymerized with a copolymerizable monomer, in which case at least one of the (meth) acrylic monomer and the copolymerizable monomer may have an acid group.

Examples of the (meth) acrylic resin include: (meth) acrylic monomers having an acid group [ e.g., [ (meth) acrylic acid, sulfoalkyl (meth) acrylate, sulfonic acid group-containing (meth) acrylamide ], or copolymers thereof, copolymers of (meth) acrylic monomers having or not having an acid group with other polymerizable monomers having an acid group [ e.g., other polymerizable carboxylic acids, polymerizable polycarboxylic acids or anhydrides, vinyl aromatic sulfonic acids ], and/or copolymerizable monomers [ e.g., alkyl (meth) acrylates, glycidyl (meth) acrylates, (meth) acrylonitrile, aromatic vinyl monomers ], copolymers of other polymer monomers having an acid group with (meth) acrylic copolymerizable monomers [ e.g., alkyl (meth) acrylates, hydroxyalkyl (meth) acrylates, glycidyl (meth) acrylates, meth) acrylonitrile, etc. ], copolymers of the (meth) acrylic copolymerizable monomers with an acid group, copolymers of the (meth) acrylic monomers with an acid group, and the like, Rosin-modified urethane acrylate, special modified acrylic resin, urethane acrylate, epoxy acrylate, urethane acrylate emulsion, and the like.

Among these (meth) acrylic resins, preferred are (meth) acrylic acid- (meth) acrylate polymers (such as acrylic acid-methyl methacrylate copolymers), and (meth) acrylic acid- (meth) acrylate-styrene copolymers (such as acrylic acid-methyl methacrylate-styrene copolymers).

The polyester resin is not particularly limited as long as it is a polymer compound obtained by polycondensing a compound having 2 or more carboxyl groups in the molecule and a compound having 2 or more hydroxyl groups, and examples thereof include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate and the like. These may be used alone or in combination of two or more.

The epoxy resin is not particularly limited, and examples thereof include epoxy resins such as bisphenol a type, bisphenol F type, phenol novolac type, polyfunctional tetra (hydroxyphenyl) ethane type or tri (hydroxyphenyl) methane type having a plurality of benzene rings, biphenyl type, triphenol methane type, naphthalene type, ortho-novolac type, dicyclopentadiene type, aminophenol type, and alicyclic type, and silicone epoxy resins. These may be used alone or in combination of two or more.

Examples of the polysiloxane include a high molecular weight alkoxysilane formed by condensation of monomers of an alkoxysilane represented by the following formula (II), and a polysiloxane having 1 or more siloxane bonds (Si-O-Si) in 1 molecule.

SiR₄(II)

(wherein R is hydrogen, hydroxy, alkoxy having 1 to 4 carbon atoms, alkyl having or not having a substituent, or phenyl having or not having a substituent; wherein at least 1 of 4R's is alkoxy having 1 to 4 carbon atoms or hydroxy.)

The structure of the polysiloxane is not particularly limited, and may be linear or branched. The polysiloxane may be a compound represented by the formula (II) alone or two or more of them may be used in combination. The weight average molecular weight of the polysiloxane is not particularly limited, but is preferably 4000 or more, more preferably 4000 to 10 ten thousand. Here, the weight average molecular weight is a value measured by Gel Permeation Chromatography (GPC).

Examples of the melamine resin include benzoguanamine/melamine/formaldehyde condensates and melamine/formaldehyde condensates. As the melamine resin, commercially available products such as EPOSTAR manufactured by japanese catalyst can be used.

The average particle diameter of the resin particles (b2) is preferably 5 to 1500nm, more preferably 10 to 1000nm, still more preferably 20 to 800nm, and particularly preferably 30 to 500 nm. When the amount is within the above range, the surface of the conductive layer tends to be easily formed into an uneven shape, and to have excellent adhesion to the adhesive layer.

The ratio of the average particle diameter of the resin particles (b2) to the average particle diameter of the conductive particles (b1) is not particularly limited, but is preferably 0.01 to 100, more preferably 0.1 to 50, and still more preferably 0.2 to 50. Within this range, in the formed conductive layer (B), the conductive particles (B1) and the resin particles (B2) can be brought into contact with each other and a part thereof can be exposed on the surface of the conductive layer, whereby the irregularities on the surface of the conductive layer can be increased and the adhesion between the conductive layer and the adhesive layer can be improved.

The content of the resin particles (b2) in the conductive composition is not particularly limited, and is preferably 10 to 5000 parts by weight, more preferably 20 to 2000 parts by weight, and still more preferably 30 to 1000 parts by weight, based on 100 parts by weight of the conductive particles (b 1). When the content of the resin particles (B2) is within the above range, the conductive particles (B1) and the resin particles (B2) can be brought into contact with each other in the formed conductive layer (B), and a part of the conductive particles can be exposed on the surface of the conductive layer, whereby the irregularities on the surface of the conductive layer can be increased, and the adhesion between the conductive layer and the adhesive layer can be improved. In addition, sufficient conductivity can be ensured. The content of the resin particles (b2) in the conductive composition is preferably 10 to 90 parts by weight, more preferably 20 to 80 parts by weight, and still more preferably 25 to 80 parts by weight, based on 100 parts by weight of the total solid content of the conductive composition. Within the above range, the adhesion and conductivity can be sufficiently ensured.

In the conductive laminate of the 1 st embodiment, the resin particles (B2) preferably have an average particle diameter of 0.2 to 15 times, more preferably 0.3 to 14 times, and still more preferably 0.4 to 12 times the thickness of the conductive layer (B). In addition, in the conductive layer laminate of the 2 nd embodiment, the resin particles (B2) have an average particle diameter of 0.2 to 15 times, preferably 0.3 to 14 times, and more preferably 0.4 to 12 times the thickness of the conductive layer (B). By setting the average particle diameter of the resin particles (B2) contained in the conductive composition and the film thickness of the conductive layer (B) after formation to the above ranges, the conductive particles (B1) and the resin particles (B2) can be brought into contact with each other in the conductive layer (B), and part of the resin particles (B2) can be exposed to the surface of the conductive layer. This increases the unevenness of the surface of the conductive layer, and improves the adhesion between the conductive layer and the adhesive layer. The film thickness of the conductive layer (B) is as described later.

The average particle diameter of the conductive particles (B1) and the resin particles (B2) contained in the conductive composition is preferably 0.1 to 20 times, more preferably 0.2 to 15 times, and still more preferably 0.3 to 10 times the film thickness of the conductive layer (B). Within the above range, the conductive particles (B1) and the resin particles (B2) can be brought into contact with each other in the conductive layer (B), and part of the resin particles (B2) can be exposed on the surface of the conductive layer. This increases the unevenness of the surface of the conductive layer, and improves the adhesion between the conductive layer and the adhesive layer. The average particle diameters of the conductive particles (b1) and the resin particles (b2) mean the average particle diameters of the conductive particles (b1) and the resin particles (b2) measured for the conductive composition.

< conductive particles (b1) and resin particles (b2) >

The total amount of the conductive particles (b1) and the resin particles (b2) is not particularly limited, but is preferably 50 to 100 parts by weight, more preferably 60 to 90 parts by weight, and still more preferably 60 to 80 parts by weight, based on 100 parts by weight of the total solid content of the conductive composition. Within the above range, the adhesion and conductivity can be sufficiently ensured.

< optional Components contained in the conductive composition >

The conductive composition may contain, in addition to the conductive particles (b1) and the resin particles (b2), a water-soluble conductive polymer, a solvent, a crosslinking agent, a catalyst, a surfactant, a slipping agent, a water-soluble antioxidant, a filler, an antifoaming agent, a neutralizing agent, a thickener, and the like.

By blending a water-soluble conductive polymer in the conductive composition, the conductivity can be improved. The water-soluble conductive polymer is a conductive polymer that is dissolved in water by adding a functional group that plays a role of a dopant and imparting water solubility. Examples of the water-soluble functional group include a sulfonic acid group. As the conductive polymer having a functional group, the conductive particles (b1) described above can be used. Specific examples of the water-soluble conductive polymer include self-doped polythiophene and self-doped polyaniline. When the conductive composition contains a water-soluble conductive polymer, the content thereof is not particularly limited, and is preferably 0.1 to 200 parts by weight, more preferably 1 to 100 parts by weight, based on 100 parts by weight of the conductive particles.

The solvent is not particularly limited, and examples thereof include: water; alcohols such as methanol, ethanol, 2-propanol, and 1-propanol; ethylene glycols such as ethylene glycol, diethylene glycol, propylene glycol, triethylene glycol, and tetraethylene glycol; glycol ethers such as ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, ethylene glycol diethyl ether, and diethylene glycol dimethyl ether; glycol ether acetates such as ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether acetate; propylene glycols such as propylene glycol, dipropylene glycol, and tripropylene glycol; propylene glycol ethers such as propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, propylene glycol dimethyl ether, and propylene glycol diethyl ether; propylene glycol ether acetates such as propylene glycol monomethyl ether acetate; ethers such as diethyl ether, diisopropyl ether, methyl tert-butyl ether, and tetrahydrofuran; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; hydrocarbons such as toluene, xylene (o-xylene, m-xylene, or p-xylene), hexane, and heptane: esters such as butyl acetate; amide compounds such as halogens, acetonitrile, N-methylformamide, N-dimethylformamide, γ -butyrolactone, and N-methylpyrrolidone; hydroxyl-containing compounds such as 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, neopentyl glycol, catechol, cyclohexanediol, cyclohexanedimethanol, glycerol, diethylene glycol monoethyl ether, and propylene glycol monomethyl ether; carbonyl group-containing compounds such as isophorone, propylene carbonate, cyclohexanone, acetylacetone, ethyl acetate, ethyl acetoacetate, methyl o-acetate, and ethyl o-formate; compounds having a sulfo group such as dimethyl sulfoxide, and the like; and a mixed solvent in which two or more solvents are mixed, including a mixed solvent of water and another solvent.

Among them, glycols, solvents having an amide group or a sulfone group, or mixed solvents of these solvents and water, which are high-boiling point and high-polarity solvents, are preferable because they have an effect of improving the conductivity of conductive particles, particularly a complex of poly (3, 4-ethylenedioxythiophene) and polystyrenesulfonic acid. Further, alcohols such as ethanol and 2-propanol, or mixed solvents of these solvents and water, which are low boiling point solvents, are preferable because they have an effect of improving the wettability of the conductive composition and an effect of accelerating the drying speed.

When the conductive composition contains a solvent other than water, the content is not particularly limited, and is preferably 70% by weight or less, preferably 0.1 to 60% by weight, and more preferably 0.2 to 50% by weight in the conductive composition.

The solvent preferably does not remain in the conductive layer (B) formed using the conductive composition. In the present specification, a substance that completely dissolves all components of the conductive composition (i.e., a "solvent") and a substance that disperses an insoluble component (i.e., a "dispersion medium") are not particularly distinguished and are both referred to as "solvents".

By compounding a crosslinking agent, the resin particles (b2) can be crosslinked, and the strength of the coating film can be improved. In addition, by compounding a crosslinking agent, the resin particles can be prevented from being dissolved in the solvent contained in the adhesive layer. The crosslinking agent is preferably soluble in the above-mentioned solvent, preferably in water. The crosslinking agent is not particularly limited, and examples thereof include melamine-based, carbodiimide-based, oxazoline-based, epoxy-based, isocyanate-based, acrylate-based, and alkoxysilane-based crosslinking agents. These crosslinking agents may be used alone, or two or more kinds thereof may be used in combination.

The melamine-based crosslinking agent is not particularly limited, and examples thereof include methylated melamine compounds and butylated melamine compounds, and NIKALAC MW-30M (manufactured by Sanwa chemical Co., Ltd.) and Cymel 303LF (manufactured by Allnex Japan K.K.) can be used as commercially available products. Two or more of them may be used in combination.

The oxazoline-based crosslinking agent is not particularly limited, and examples thereof include addition polymerizable oxazoline compounds such as 2-isopropenyl-2-oxazoline, 2-vinyl-2-oxazoline and 2-vinyl-4-methyl-2-oxazoline, and commercially available products thereof include Epocros WS-300, WS-500 and WS-700 (manufactured by Nippon catalyst Co., Ltd.). Two or more of them may be used in combination.

The epoxy-based crosslinking agent is not particularly limited, and examples thereof include aliphatic polyepoxides such as ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, sorbitol polyglycidyl ether, pentaerythritol polyglycidyl ether, etc., and as commercially available products, Denacol EX-521, EX-614 (manufactured by NagasemetremeX Co., Ltd.) and the like can be used. Two or more of them may be used in combination.

Examples of the alkoxysilane-based crosslinking agent include alkoxysilanes represented by the following formula (II) and alkoxysilane oligomers formed by condensation of alkoxysilanes, and include oligomers having 1 or more siloxane bonds (Si-O-Si) in 1 molecule.

SiR₄(II)

(wherein R is hydrogen, hydroxy, alkoxy having 1 to 4 carbon atoms, alkyl having or not having a substituent, or phenyl having or not having a substituent; wherein at least 1 of 4R's is alkoxy having 1 to 4 carbon atoms or hydroxy.)

The structure of the alkoxysilane oligomer is not particularly limited, and may be linear or branched. The alkoxysilane oligomer may be the compound represented by the formula (II) alone or two or more of them may be used in combination. The weight average molecular weight of the alkoxysilane oligomer is not particularly limited, but is preferably more than 152 and 4000 or less, more preferably 500 to 2500. Here, the weight average molecular weight is a value measured by Gel Permeation Chromatography (GPC).

When the conductive composition contains the thermosetting resin particles (b2) and the crosslinking agent, the catalyst for crosslinking the thermosetting resin particles (b2) is not particularly limited, and examples thereof include a photopolymerization initiator and a thermal polymerization initiator.

By blending a surfactant in the conductive composition, the leveling property of the conductive composition can be improved. By using such a conductive composition, a uniform conductive layer can be formed.

The surfactant is not particularly limited as long as it has a leveling property improving effect, and examples thereof include: silicone compounds such as polyether-modified polydimethylsiloxane, polyether-modified siloxane, polyether ester-modified hydroxyl-containing polydimethylsiloxane, polyether-modified acryloyl-containing polydimethylsiloxane, polyester-modified acryloyl-containing polydimethylsiloxane, perfluoropolyether-modified polydimethylsiloxane, and perfluoropolyether-modified polydimethylsiloxane; fluorine-based compounds such as perfluoroalkyl carboxylic acids and perfluoroalkyl polyoxyethylene alcohols; polyether compounds such as polyoxyethylene alkylphenyl ether, propylene oxide polymer and ethylene oxide polymer; carboxylic acids such as coconut oil fatty acid amine salts and rosin; ester compounds such as castor oil sulfates, phosphates, alkyl ether sulfates, sorbitan fatty acid esters, sulfonates, and succinates; sulfonate compounds such as alkylaryl sulfonic acid amine salts and 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 surfactants may be used alone or in combination of two or more. Among these surfactants, a siloxane-based compound and a fluorine-based compound are preferable because of their excellent dispersion stability when incorporated in the conductive composition.

When the conductive composition contains a surfactant, the content thereof is not particularly limited, and is preferably 0 to 40% by weight, more preferably 0.01 to 10% by weight, and further preferably 0.1 to 5% by weight, based on the solid content of the conductive composition.

The sliding agent is not particularly limited, and examples thereof include hydrocarbon resins, oxygen-containing fatty acids, aliphatic alcohols, silicone resins, fluorine resins, and the like. These sliding agents may be used alone, or two or more of them may be used in combination.

The content of the sliding agent is not particularly limited, but is preferably 0 to 1% by weight, more preferably 0 to 0.8% by weight, in the solid content of the conductive composition. When the amount is within the above range, adhesion between the conductive layer and the adhesive layer can be secured.

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

The filler is not particularly limited, and examples thereof include an inorganic filler and an organic filler having a crosslinked structure. Specific examples of the material of the inorganic filler are not particularly limited, and include, for example: silica such as colloidal silica, hollow silica and fumed silica, and metal oxides such as titania and zirconia; and organic-inorganic composites such as a core-shell acrylic-silica composite in which a thermoplastic or thermosetting acrylic resin is coated with silica, a core-shell melamine-silica composite in which a melamine resin is coated with silica, a core-shell acrylic-silica composite in which a thermoplastic or thermosetting acrylic resin is coated with silica, a core-shell melamine-silica composite in which silica is coated with a melamine resin, an acrylic-silica composite in which small silica is supported by a thermoplastic or thermosetting acrylic resin, and the like. Specific examples of the material of the organic filler are not particularly limited, and examples thereof include a fluororesin, an acrylic resin, a melamine resin, and a urethane rubber. These fillers may be used alone or in combination of two or more.

< method for Forming conductive layer >

The conductive layer is formed by applying a conductive composition to the surface of the thermoplastic resin substrate (a). The conductive layer may be formed by directly applying the conductive composition onto the thermoplastic resin substrate (a), or may be formed by providing another layer such as an undercoat layer on the substrate in advance and applying the layer.

The conductive layer can be obtained by applying a conductive composition to at least one surface of the thermoplastic resin substrate (a) and then performing a heating treatment. The method for applying the conductive composition to at least one surface of the thermoplastic resin substrate (a) is not particularly limited, and known methods can be used, and examples thereof include roll coating, bar coating, dip coating, spin coating, casting, die coating, blade coating, bar coating, gravure coating, curtain coating, spray coating, blade coating, slit coating, relief (letterpress) printing, stencil (screen) printing, offset (offset) printing, gravure (gravure) printing, spray printing, inkjet printing, and pad printing.

Before applying the conductive composition to at least one surface of the thermoplastic resin substrate (a), the surface of the thermoplastic resin substrate (a) may be subjected to a surface treatment in advance as necessary. Examples of the surface treatment include corona treatment, excimer treatment, plasma treatment, glow treatment, ozone treatment, ITRO treatment, flame treatment, and primer treatment. The corona treatment can be performed, for example, by discharging in atmospheric air using a corona treatment machine manufactured by spring motor corporation. The plasma treatment can be performed, for example, by performing discharge in atmospheric air or an inert gas atmosphere such as nitrogen or argon by a plasma discharge machine manufactured by hydropneumatic chemical company. The excimer treatment may be performed by irradiating an excimer lamp. The excimer lamp is a UV lamp having a wavelength of 180nm or less in which Xe is sealed. The glow treatment and the ozone treatment may be performed by a conventional method. These treatments may be applied to the thermoplastic resin substrate (a) in combination.

The heat treatment after the coating of the conductive composition is not particularly limited, and may be performed according to a known method, for example, using a forced air oven, an infrared oven, a vacuum oven, or the like. When the conductive composition contains a solvent, the solvent is removed by heat treatment.

The heating temperature of the conductive composition is not particularly limited, but is preferably 40 to 110 ℃, more preferably 45 to 100 ℃, and still more preferably 45 to 90 ℃. When the temperature exceeds 110 ℃, the resin particles melt, and the surface of the conductive layer (B) is difficult to maintain a concavo-convex shape, and the adhesion to the adhesive layer is reduced. The treatment time of the heat treatment is not particularly limited, but is preferably 0.5 to 5 minutes, and more preferably 0.5 to 3 minutes.

The thickness of the conductive layer (B) formed on the thermoplastic resin substrate (A) is preferably 5 to 500nm, more preferably 10 to 200nm, and still more preferably 15 to 150 nm. The film thickness of the conductive layer (B) is a value measured by the method described in the examples.

The surface resistivity of the conductive layer is not particularly limited, but is preferably 10⁴～10⁹Omega/□, more preferably 10⁵～10⁸Omega/□. Here, the surface resistivity of the conductive layer is a value measured by the method described in examples after the conductive layer (B) is formed on the thermoplastic resin base material (a).

In the first aspect of the conductive laminate 1, in order to improve the adhesion between the conductive layer (B) and the adhesive layer (C), the spread area ratio Sdr of the surface of the conductive layer (B) in contact with the adhesive layer (C) is 0.001 to 0.3, preferably 0.002 to 0.25, and more preferably 0.01 to 0.2. In the conductive laminate of the 2 nd embodiment, in order to improve the adhesion between the conductive layer (B) and the adhesive layer (C), the spread area ratio Sdr of the surface of the conductive layer (B) in contact with the adhesive layer (C) is preferably 0.001 to 0.3, more preferably 0.002 to 0.25, and still more preferably 0.01 to 0.2. The spread area ratio Sdr is a surface roughness calculated from the entire (planar) sample surface, and indicates an increase in the surface area relative to a perfectly smooth surface, and can exclude the influence of waviness or inclination of the sample surface. When the spreading area ratio Sdr is within the above range, the conductive layer (B) and the adhesive layer (C) tend to have excellent adhesion and transparency. The spreading area ratio Sdr of the conductive layer is a value measured by the method described in the examples after the conductive layer (B) is formed on the thermoplastic resin base material (a).

The surface roughness Sa of the surface of the conductive layer (B) in contact with the adhesive layer (C) is preferably 10 to 200nm, more preferably 12 to 150nm, and still more preferably 15 to 140 nm. When the surface roughness Sa is less than 10nm, adhesion between the conductive layer (B) and the adhesive layer (C) tends not to be obtained; when the average particle diameter exceeds 200nm, transparency required for an optical film tends not to be obtained. The surface roughness Sa is the roughness measured by cutting out a line on the surface of the test piece. The surface roughness Sa of the conductive layer in the present invention is a value measured by the method described in examples after the conductive layer (B) is formed on the thermoplastic resin substrate (a).

The surface roughness Ra of the surface of the conductive layer (B) that is in contact with the adhesive layer (C) is preferably 5 to 100nm, more preferably 7 to 95nm, and still more preferably 15 to 90 nm. When the surface roughness Ra is less than 5nm, adhesion between the conductive layer (B) and the adhesive layer (C) tends not to be obtained; when the average particle diameter exceeds 100nm, transparency required for an optical film tends not to be obtained. The surface roughness Ra is a roughness measured on the entire surface of the sample. The surface roughness Ra of the conductive layer in the present invention is a value measured by the method described in examples after the conductive layer (B) is formed on the thermoplastic resin base material (a).

< adhesive layer (C) >

The adhesive layer (C) is laminated on the surface of the conductive layer (B) which is not in contact with the thermoplastic resin substrate (a). The adhesive layer is formed using an adhesive composition containing an adhesive. The binder is not particularly limited, and conventionally known binders can be used, and specific examples thereof include: examples of the thermoplastic resin include (meth) acrylic resins obtained by homopolymerizing or copolymerizing various (meth) acrylate monomers, silicone resins such as ethylene/vinyl acetate copolymer resins and silicone rubbers having a dimethylsiloxane skeleton, urethane resins obtained by addition-polymerizing a polyol and a polyisocyanate, natural rubbers, styrene-isoprene-styrene block copolymers (SIS block copolymers), styrene-butadiene-styrene block copolymers (SBS block copolymers), styrene-ethylene-butylene-styrene block copolymers (SEBS block copolymers), styrene-butadiene rubbers, polybutadiene, polyisoprene, polyisobutylene, butyl rubbers, and rubber-based resins such as chloroprene rubbers. Among these, particularly preferred are (meth) acrylic resins, silicone resins, and urethane resins that have excellent chemical stability, high freedom in chemical structure design, and easy adjustment of adhesive force. Further, (meth) acrylic resins and polyurethane resins are also preferable from the viewpoint of excellent transparency in particular.

In addition to the binder, a crosslinking agent, an antistatic agent, a silane coupling agent, a surfactant, a solvent, and the like may be added to the binder composition.

As the crosslinking agent, a polyfunctional metal chelate or an organic crosslinking agent can be used. The polyfunctional metal chelate compound is a substance In which a polyvalent metal is covalently or coordinately bonded to an organic compound, and examples of the polyvalent metal atom include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, and Ti. Examples of the atom in the organic compound to be covalently or coordinately bonded include an oxygen atom, and examples of the organic compound include an alkyl ester, an alcohol compound, a carboxylic acid compound, an ether compound, and a ketone compound. Examples of the organic crosslinking agent include isocyanate-based, peroxide-based, epoxy-based, and imine-based organic crosslinking agents. The content of the crosslinking agent in the adhesive composition is not particularly limited, and is, for example, preferably 10 parts by weight or less, more preferably 0.01 to 5 parts by weight, and still more preferably 0.02 to 3 parts by weight, based on 100 parts by weight of the adhesive.

As the antistatic agent, an ionic compound is preferable from the viewpoint of compatibility with the binder and transparency, and an ionic liquid is particularly preferable. By adding an antistatic agent to the adhesive composition, the conductivity of the entire laminate can be improved. The content of the antistatic agent is preferably 0.01 to 30 parts by weight, more preferably 0.05 to 20 parts by weight, based on 100 parts by weight of the binder (e.g., (meth) acrylic resin).

As a method for laminating the adhesive layer (C) on the conductive layer (B), a conventionally known method can be used, and examples thereof include: a transfer method of transferring the adhesive layer formed on the release film to the conductive layer (B); a coating method in which an adhesive composition containing an adhesive is coated on the conductive layer (B) and crosslinked or heat-dried; and the like. Among these, the transfer method is preferable because it can be applied to the thermoplastic resin substrate (a) having low solvent resistance and the surface properties of the conductive layer (B) can be easily maintained.

When the adhesive layer (C) is laminated on the conductive layer (B) by the transfer method, first, an adhesive composition is applied to a release film, and drying, ultraviolet irradiation, and/or heating are performed, thereby forming an adhesive layer on the release film. The application of the pressure-sensitive adhesive composition to the release film can be carried out by a conventionally known method, and specifically, the method described above as a method of applying the conductive composition to at least one surface of the thermoplastic resin substrate (a) can be mentioned. The surface of the formed adhesive layer not in contact with the release film is brought into contact with the conductive layer (B), whereby the adhesive layer (C) can be transferred to the conductive layer (B).

The thickness of the adhesive layer (C) is not particularly limited, but is preferably 5 to 100. mu.m.

< method for producing conductive laminate >

The method for producing a conductive laminate of the present invention is characterized by comprising the following steps (1) and (2): (1) a step of forming a conductive layer (B) by applying a conductive composition (B) containing conductive particles (B1) and resin particles (B2) onto a thermoplastic resin substrate (a); and (2) a step of laminating an adhesive layer (C) on the surface of the conductive layer (B) by a transfer method.

The thermoplastic resin base material (a), the conductive layer (B), and the adhesive layer (C) are as described above. In the step (1), the conductive composition (b) to be applied is preferably heated at 40 to 110 ℃ for 0.5 to 5 minutes. The heating temperature and time are as described above for the method of forming the conductive layer.

< conductive composition >)

The conductive composition of the present invention is characterized by containing conductive particles (b1) and resin particles (b 2). The conductive particles (b1) and the resin particles (b2) are as described above. The conductive composition can be suitably used for forming the conductive layer (B) in the conductive laminate.

< optical Member >

The optical member of the present invention is characterized by comprising the above-described conductive laminated body. The optical member is not particularly limited as long as high adhesion is required between the conductive layer and the adhesive layer while maintaining conductivity, and examples thereof include a polarizing plate, a surface protective film, a transparent conductive film, and an antistatic film.