Laminated film

Abstract

Provided is a laminated film having scratch resistance in practical use while having excellent antistatic properties. The laminated film according to the present invention comprises a configuration in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one surface of the side surface of a base material film, wherein the surface resistivity of the cured resin layer (B) side of the laminated film is 1.0 × 107 ohms per square or less, the resin layer (A) and the cured resin layer (B) contain an antistatic agent, and the surface resistivity of the cured resin layer (B) is higher than the surface resistivity of the resin layer (A).

Description

Laminated film

[0001] The present invention relates to a laminated film, and more particularly to a laminated film with excellent antistatic properties and abrasion resistance.

[0002] In recent years, the demand for image display devices with displays, such as smartphones and tablet devices, has been expanding further. Various protective films are used on these displays. Plastic films such as triacetylcellulose film, cycloolefin film, polyester film, acrylic film, polycarbonate film, and transparent polyimide film are used as protective films for displays due to their optical properties, such as transparency. However, these plastic films exhibit high electrical insulation properties, making them prone to static charge buildup and attracting dust to their surfaces.

[0003] Therefore, it has been common practice to provide an antistatic layer on a base film. Among these methods, coating with electronically conductive compounds such as polythiophene is known to exhibit superior antistatic properties compared to ionically conductive compounds such as anionic and cationic compounds.

[0004] For example, Patent Document 1 discloses a polyester film having a coating layer that has good appearance quality and antistatic performance that does not deteriorate easily over time. This coating layer is formed on one side of the polyester film by applying a coating solution containing a conductive compound, a polyglycerin-based compound, and an epoxy-based crosslinking agent to the polyester film and drying it, and the surface resistivity is 10 ４ ~10 ５It is disclosed that the film has excellent antistatic properties of approximately Ω. Furthermore, Patent Document 2 discloses a laminated polyester film having a cured resin layer formed from a specific resin composition containing a polythiophene compound, which does not experience a decrease in antistatic properties regardless of the usage environment even if some damage (external force) is applied to the surface, and can suppress problems caused by the adhesion or entrapment of foreign matter due to static electricity. It is also disclosed that by including a mold release agent, the load applied to the surface of the cured resin layer during the processing step, such as in contact between the conveyor roll and the cured resin layer, can be reduced.

[0005] International Publication WO11 / 122664, Japanese Patent Publication No. 2024-105989

[0006] However, protective films for displays and the like need to satisfy various surface properties. While the laminated film described in Patent Document 1 has excellent antistatic properties, it cannot satisfy abrasion resistance, such as preventing scratches during the display manufacturing process. Similarly, the laminated polyester film described in Patent Document 2 still has room for improvement to satisfy practical abrasion resistance.

[0007] Normally, a hard coat layer is added to the surface to improve the durability of the laminated film surface. However, when a hard coat layer is added on top of an antistatic layer, the antistatic properties of the hard coat layer surface decrease, and sufficient antistatic properties cannot be maintained. In other words, the overall surface resistivity of the laminated film increases, and this layer configuration cannot satisfy the practical antistatic properties required for a surface protective film.

[0008] Therefore, the present invention provides a laminated film that can achieve both excellent antistatic properties and abrasion resistance. More specifically, the present invention provides a laminated film that maintains low surface resistivity without a decrease in antistatic properties, even when a cured resin layer (hard coat layer) that satisfies practical abrasion resistance is provided on the antistatic layer.

[0009] In view of the above circumstances, the inventors of the present invention have conducted intensive studies and, as a result, have found that the above problems can be solved by providing a structure in which a resin layer (A) and a cured resin layer (B) having a specific structure are laminated, and have thus completed the present invention. That is, the present invention provides the following [1] to

[13] .

[0010] [1] A laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one surface of a base film, wherein the surface resistivity of the laminated film on the side of the cured resin layer (B) is 1 × 10 ７ Ω / □ or less, the resin layer (A) and the cured resin layer (B) contain an antistatic agent, and the surface resistivity of a single layer of the cured resin layer (B) is higher than the surface resistivity of a single layer of the resin layer (A). [2] The laminated film according to [1] above, wherein the antistatic agent contained in the cured resin layer (B) is not segregated. [3] The laminated film according to [1] or [2] above, wherein the antistatic agent contained in the cured resin layer (B) is an antistatic agent capable of forming a conductive path with the antistatic agent contained in the resin layer (A). [4] A laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one surface of a base film, wherein the surface resistivity of the laminated film on the side of the cured resin layer (B) is 1 × 10 ７ Ω / □ or less, the resin layer (A) and the cured resin layer (B) contain an antistatic agent, and the coefficient of variation (CV) of the element concentration derived from the antistatic agent in the cured resin layer (B), calculated from the quantitative mapping of the elements derived from the antistatic agent detected by scanning electron microscope (SEM-EDS) analysis, satisfies the following (1). (1) In the quantitative mapping, the coefficient of variation of the element concentration derived from the antistatic agent in the entire mapping region is CV ＡＬＬ , the mapping region is divided into 3 parts in the thickness direction and 5 parts in the width direction, a total of 15 parts, and when the coefficient of variation of the element concentration derived from the antistatic agent in each region is CVn (n = 1 to 15), the overall coefficient of variation CV ＡＬＬ and the maximum value CV of the coefficient of variation of each region ｍａｘ The difference between, and the absolute value of the ratio of the overall coefficient of variation CV ＡＬＬ , and the overall coefficient of variation CV ＡＬＬ And the minimum value CV of the coefficient of variation of each regionｍｉｎ The difference and the overall coefficient of variation CV ＡＬＬ The absolute values ​​of the ratios of and are both 20% or less. [5] The laminated film according to [4] above, wherein the average value C of the elemental concentration derived from the antistatic agent in the cured resin layer (B) satisfies the following (2). (2) In the quantitative mapping, the average value of the elemental concentration derived from the antistatic agent in the entire mapping area is C ＡＬＬ When the mapping region is divided into three parts in the thickness direction, and the average value of the elemental concentration derived from the antistatic agent in each region is taken as Cn (n=1 to 3), the maximum value C of the average value in each region is... ｍａｘ and minimum value C ｍｉｎ The difference between the difference and the overall average value C ＡＬＬ The ratio is 20% or less. [6] A laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one side surface of a base film, wherein the surface resistivity of the cured resin layer (B) side of the laminated film is 1 × 10 ７A laminated film having a static charge of Ω / □ or less, wherein the resin layer (A) and the cured resin layer (B) contain an antistatic agent, the antistatic agent contained in the resin layer (A) contains an electronically conductive compound, and the antistatic agent contained in the cured resin layer (B) contains an electronically conductive metal oxide. [7] The laminated film according to any one of [1] to [6] above, wherein the antistatic agent contained in the cured resin layer (B) contains an electronically conductive compound. [8] The laminated film according to [7] above, wherein the antistatic agent contained in the cured resin layer (B) contains phosphorus-doped tin oxide as an electronically conductive compound. [9] The laminated film according to any one of [1] to [8] above, wherein the antistatic agent contained in the resin layer (A) contains an electronically conductive compound.

[10] The laminated film according to [9] above, wherein the antistatic agent contained in the resin layer (A) contains a polythiophene compound as an electronically conductive compound.

[11] A laminated film according to any one of [1] to

[10] above, wherein the antistatic agent contained in the resin layer (A) contains the following compound (A-a) and at least one of (A-b) and (A-c): (A-a) (A-a1) A polymer obtained by doping a compound consisting of thiophene or a thiophene derivative with another anionic compound, and (A-a2) A polymer obtained by self-doping a compound consisting of thiophene or a thiophene derivative having an anionic group in it (A-b) A (meth)acrylic polymer having a styrene structure (A-c) (A-c1) A compound obtained by doping polyglycerin and (A-c2) An alkylene oxide adduct to polyglycerin, or a derivative thereof

[12] A laminated film according to any one of [1] to

[11] above, wherein the thickness of the resin layer (A) is 0.002 to 1.0 μm.

[13] A laminated film according to any one of [1] to

[12] above, wherein the thickness of the cured resin layer (B) is 0.5 to 10 μm.

[14] A laminated film according to any one of [1] to

[13] above, wherein the surface resistivity of the cured resin layer (B) of the laminated film is lower than the surface resistivity of a single layer of the cured resin layer (B).

[15] A laminated film according to any one of [1] to

[14] above, for surface protection.

[16] A laminated film according to any one of [1] to

[15] above, for display purposes.

[0011] According to the present invention, it is possible to provide a laminated film that has excellent antistatic properties while also possessing practical abrasion resistance.

[0012] Next, the present invention will be described based on examples of embodiments. However, the present invention is not limited to the embodiments described below.

[0013] A laminated film according to an example of an embodiment of the present invention (hereinafter sometimes referred to as "this laminated film") is a laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one side surface of a base film (hereinafter sometimes referred to as "this base film"), wherein the surface resistivity of the cured resin layer (B) side of the laminated film is 10 ７ The laminated film has a resistivity of Ω / □ or less, and the resin layer (A) and cured resin layer (B) contain an antistatic agent, with the surface resistivity of a single layer of cured resin layer (B) being higher than that of a single layer of resin layer (A). With this configuration, even though the antistatic properties of cured resin layer (B) are inferior to those of resin layer (A), the laminated film can exhibit antistatic properties equivalent to those of resin layer (A). Note that this laminated film may also include other layers such as an adhesive layer or a release layer, as long as it has the above configuration.

[0014] <Base Film> The base film is not limited in terms of material and composition, but polyester film or polyimide film is preferred, and polyester film is particularly preferred, due to its excellent transparency, heat resistance, flexibility, and impact resistance.

[0015] The base film may be a single-layer or multi-layer structure. If the base film is a multi-layer structure, it may be a four-layer or more multi-layer structure, in addition to a two-layer or three-layer structure, as long as it does not exceed the essence of the present invention.

[0016] Whether the base film is a single-layer or multi-layer structure, it is preferable that the main component resin of each layer is polyester or polyimide (PI). Such a film is referred to as a "polyester film" or "polyimide film." In this context, "main component resin" refers to the resin that accounts for the largest proportion of each layer of the base film, for example, a resin that accounts for 50% by mass or more, particularly 70% by mass or more, and especially 80% by mass or more (including 100% by mass) of the resins constituting the base film. Note that each layer constituting the base film may contain other resins or components other than polyester or polyimide, as long as its main component resin is polyester or polyimide.

[0017] (Polyester) The polyester (hereinafter sometimes referred to as "this polyester") as the main component resin of each layer constituting the base film may be homopolyester or copolymer polyester.

[0018] When the polyester is a homopolyester, it is preferable to obtain it by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid. Examples of the aliphatic glycol include ethylene glycol, diethylene glycol, and 1,4-cyclohexanedimethanol.

[0019] Furthermore, if the polyester is a copolymerized polyester, its dicarboxylic acid component can be one or more of the following: isophthalic acid, phthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, sebacic acid, etc. On the other hand, its glycol component can be one or more of the following: ethylene glycol, diethylene glycol, propylene glycol, butanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, etc.

[0020] As a polymerization catalyst for polyester, known catalysts such as antimony compounds, germanium compounds, titanium compounds, and aluminum compounds can be used. Of these, in the present invention, polyester polymerized using antimony compounds or titanium compounds as catalysts is preferred. Typical examples of polyesters include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), and polyethylene furanoate (PEF). Among these, PET and PEN are preferred in terms of handling, with PET being the most preferred. When the main component resin of each layer constituting the base film is, for example, polyethylene terephthalate, the film is referred to as a "polyethylene terephthalate film." The same applies when other resins are the main component resins.

[0021] (Polyimide) In addition to polyester films, polyimide films are also suitable as base films. Regarding the imidation of the polyimide, for example, a method is exemplified in which a diamine and a dianhydride, particularly an aromatic dianhydride and an aromatic diamine, are polymerized with polyamic acid in a 1:1 equivalent ratio, and then imidated. Examples of the aromatic dianhydride include 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA), 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dianhydride (TDA), pyromellitic acid dianhydride (1,2,4,5-benzenetetracarboxylic acid dianhydride, PMDA), benzophenonetetracarboxylic acid dianhydride (BTDA), biphenyltetracarboxylic acid dianhydride (BPDA), and biscarboxyphenyldimethylsilane dianhydride (SiDA). These may be used individually or in combination of two or more. Examples of aromatic diamines include oxydianiline (ODA), p-phenylenediamine (pPDA), m-phenylenediamine (mPDA), p-methylenedianiline (pMDA), m-methylenedianiline (mMDA), bistrifluoromethylbenzidine (TFDB), cyclohexanediamine (13CHD, 14CHD), and bisaminohydroxyphenylhexafluoropropane (DBOH). These may be used individually or in combination of two or more.

[0022] (Other resin components) Each layer constituting the base film may have a resin other than polyester and polyimide as its main component. Examples of such main component resins include epoxy, polyarylate, polyethersulfone, polycarbonate, polyetherketone polysulfone, polyphenylene sulfide, polyester liquid crystal polymer, triacetylcellulose, cellulose derivatives, polypropylene, polyamides, polycycloolefins, and the like.

[0023] (Particles) The base film may contain particles for the purpose of ensuring the film's runability, providing slipperiness to the film surface, and preventing scratches during each process. The type of particles is not particularly limited as long as they can provide slipperiness. Examples include inorganic particles such as silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide, and titanium oxide, and organic particles such as acrylic resin, styrene resin, urea resin, phenolic resin, epoxy resin, and benzoguanamine resin. These may be used individually or in combination of two or more. Furthermore, precipitated particles obtained by precipitating and finely dispersing a portion of a metal compound such as a catalyst during the polyester manufacturing process can also be used.

[0024] The shape of the above particles is not particularly limited. For example, they may be spherical, lumpy, rod-shaped, flattened, etc. There are also no particular restrictions on the hardness, specific gravity, color, etc., of the above particles. Two or more types of these particles may be used in combination as needed.

[0025] The average particle size of the above particles is preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 2.5 μm or less. If it is 5 μm or less, the surface roughness of the base film does not become too rough, and problems when laminating the resin layer (A) and the cured resin layer (B) can be suppressed. On the other hand, the average particle size of the above particles is preferably 0.01 μm or more, and even more preferably 0.5 μm or more.

[0026] The particle content is preferably 5% by mass or less in the base film, more preferably 0.0003% by mass or more and 3% by mass or less, and even more preferably 0.01% by mass or more and 2% by mass or less. If the particle content is within the above range, the surface roughness of the base film will not be too rough, and problems when laminating the resin layer (A) or the cured resin layer (B) can be suppressed.

[0027] The method for adding particles to the base film is not particularly limited, and conventionally known methods can be employed. For example, they can be added at any stage in the production of the raw material resin, such as polyester. If the base film is polyester, it is preferable to add the particles after the esterification or transesterification reaction is completed.

[0028] (Other components) The base film may contain other components as needed, such as conventionally known antioxidants, antistatic agents, heat stabilizers, lubricants, dyes, pigments, ultraviolet absorbers, etc.

[0029] (Thickness of the base film) The thickness of the base film is preferably 5 to 100 μm, and more preferably 10 to 75 μm from the viewpoint of reducing the overall thickness of the layer, and even more preferably 25 to 60 μm.

[0030] (Manufacturing Method) The base film can be formed, for example, by melt film formation or solution film formation using a resin composition. In the case of a multilayer structure, co-extrusion may be used. It may also be uniaxially oriented or biaxially oriented, and from the viewpoint of rigidity, a biaxially oriented film is preferred.

[0031] Generally, first, undried or dried polyester chips are supplied to a melt extruder using a known method, and heated to a temperature above the melting point of each polymer to melt them. Next, the molten polymer is extruded from the die and rapidly cooled and solidified on a rotating cooling drum to a temperature below the glass transition temperature to obtain a substantially amorphous, unoriented sheet. In this case, it is preferable to improve the adhesion between the sheet and the rotating cooling drum in order to improve the flatness of the sheet, and in the present invention, electrostatic application adhesion and / or liquid coating adhesion are preferably employed.

[0032] From the viewpoint of film strength, it is preferable to stretch the sheet obtained as described above in two axes to form a film. Specifically regarding the stretching conditions, the unstretched sheet is stretched in the longitudinal direction (machine direction) at 70 to 145°C, preferably 80 to 120°C, at a stretching ratio of 2.0 to 4.5 times, preferably 3.0 to 4.0 times, to obtain a uniaxially oriented film. Next, it is stretched in the transverse direction (width direction), which is perpendicular to the longitudinal direction (machine direction), at 90 to 160°C, at a stretching ratio of 3.0 to 6.5 times, preferably 3.5 to 6.0 times, to obtain a biaxially oriented film. Subsequently, it is preferable to perform heat treatment (heat setting) at 210 to 260°C under tension or under relaxation of 30% or less for 10 to 600 seconds. Then, it is preferable to relax the sheet by 1 to 10% in the longitudinal and / or transverse directions in the highest temperature zone of the heat treatment and / or the cooling zone at the heat treatment exit. The longitudinal direction (machine direction) of the film refers to the direction in which the film progresses during the film manufacturing process, i.e., the winding direction of the film roll. The transverse direction (width direction) refers to the direction parallel to the film surface and perpendicular to the longitudinal direction, that is, the direction parallel to the central axis of the roll when the film is in a roll form.

[0033] <Resin layer (A)> This laminated film has a laminated structure in which an antistatic resin layer (A) is provided on at least one side surface of the base film, and a cured resin layer (B) is further provided on the surface side thereof. The resin layer (A) may be provided on only one side of the base film or on both sides.

[0034] The resin layer (A) contains an antistatic agent and has low surface resistivity, possessing the property of being able to leak charge (antistatic properties). In order to achieve good antistatic properties, it is preferable that the surface resistivity of a single layer of resin layer (A) be as low as possible, 1 × 10⁻⁶ ７ It is preferable that the value is Ω / □ or less, and more preferably 5 × 10 ６ Ω / □ or less, particularly preferably 1 × 10 ６ It is less than or equal to Ω / □. In this invention, the surface resistivity of a single layer of resin layer (A) is the value measured by the following method.

[0035] (Method for measuring the surface resistivity of a single layer of resin layer (A)) A sample was prepared with a resin layer (A) / base film (PET) configuration, in which a resin layer (A) was provided on one side of a base film. After conditioning the sample in a measurement atmosphere of 23°C and 50% RH for 30 minutes, the surface resistivity of the resin layer (A) side of the sample was measured using a "4339B High Resistance Meter" manufactured by Resident Technology Co., Ltd. Measurement conditions: Set voltage 0.1V, voltage application time: 15 seconds

[0036] The resin layer (A) is formed from a resin composition containing an antistatic agent.

[0037] (Antistatic Agent) Generally, ionic conductive compounds such as anionic compounds and cationic compounds, hydrophilic nonionic compounds such as polyethylene oxide, and electronically conductive compounds are known as antistatic agents. In the present invention, electronically conductive compounds are preferred as the antistatic agent used in the resin layer (A), and specific examples of electronically conductive compounds include electronically conductive organic compounds such as polyacetylene, polyphenylene, polyaniline, polypyrrole, polyisothianaphthene, and polythiophene. Among these, the following compound (A-a) is preferred. (A-a) A polymer obtained by alone or copolymerizing thiophene or a thiophene derivative. The above compound (A-a) is a polymer obtained by doping a compound consisting of (A-a1) thiophene or a thiophene derivative with another anionic compound, or (A-a2) a polymer that has an anionic group in a compound consisting of thiophene or a thiophene derivative and is self-doped, and is preferred in that it has excellent conductivity. One or more of these electronically conductive compounds may be used.

[0038] Examples of the above compound (A-a) include those obtained by polymerizing the compound of formula (1) or (2) below in the presence of a polyanion. The polymer obtained by polymerizing formula (1) below in the presence of a polyanion and the polymer obtained by polymerizing formula (2) below in the presence of a polyanion may be used in combination.

[0039]

[0040] In the above formula (1), R １ and R２ Each of these independently represents a hydrogen atom or an aliphatic hydrocarbon group, alicyclic hydrocarbon group, aromatic hydrocarbon group, etc., having 1 to 20 carbon atoms.

[0041]

[0042] In equation (2) above, n represents an integer from 1 to 4.

[0043] Examples of polyanions used during polymerization include poly(meth)acrylic acid, polymaleic acid, polystyrene sulfonic acid, and polyvinyl sulfonic acid. A method for producing such polymers can be employed, for example, the method described in Japanese Patent Publication No. 7-90060.

[0044] In the present invention, a compound of formula (2) in which n is 2 and polystyrene sulfonic acid is used as the polyanion is preferably used.

[0045] Furthermore, if these polyanions are acidic, some or all of them may be neutralized. Ammonia, organic amines, and alkali metal hydroxides are preferred bases for neutralization.

[0046] The content of the antistatic agent in the resin layer (A) is preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 60% by mass or less, and particularly preferably 30% by mass or less. By keeping the upper limit of the antistatic agent content below the above, it is easier to obtain a resin layer (A) with sufficient transparency and antistatic performance. Furthermore, the amount of antistatic agent in the resin layer (A) is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass, and particularly preferably 5% by mass. By keeping the lower limit of the antistatic agent content above the above, the required antistatic performance can be achieved with a thinner resin layer (A). As the thickness decreases, the appearance quality and transparency of the resin layer (A) improve, and the cost also decreases. In addition, film blocking can be suppressed.

[0047] The resin layer (A) is preferably formed from a resin composition containing, in addition to the above-mentioned antistatic agent, at least one of the following compounds (A-b) and (A-c): (A-b) a (meth)acrylic polymer having a styrene structure; (A-c) one or more compounds selected from (A-c1) polyglycerin and (A-c2) alkylene oxide adducts to polyglycerin, or their derivatives.

[0048] Compound (A-b) is a (meth)acrylic polymer having a styrene structure. By using compound (A-b) in combination, the durability of the antistatic performance of the resin layer (A) can be improved. The styrene structure refers to styrene and styrene derivatives, and for example, alkyl groups such as methyl groups and ethyl groups, or phenyl groups may be introduced as substituents to styrene. From the viewpoint of preventing oligomer precipitation due to heat treatment, preferably it is styrene substituted with alkyl groups having 4 or fewer carbon atoms, or styrene without substituents, and more preferably it is styrene.

[0049] (Meth)acrylic polymers are polymers whose constituent units are (meth)acrylic acid or alkyl (meth)acrylate, and compound (b) is a copolymer of styrene or a styrene derivative with (meth)acrylic acid or alkyl (meth)acrylate. In this invention, when the expression "(meth)acrylic acid" is used, it means either or both of "acrylic acid" and "methacrylic acid". Similarly, "(meth)acrylate" means either or both of "acrylate" and "methacrylate", and "(meth)acryloyl" means either or both of "acryloyl" and "methacryloyl".

[0050] Examples of the alkyl (meth)acrylate ester include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and lauryl (meth)acrylate. Alternatively, alkyl (meth)acrylate esters containing hydroxyl groups, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, may also be used. These may be used individually or in combination of two or more. Among these, (meth)acrylic acid is preferred, and acrylic acid is more preferred, from the viewpoint of preventing oligomer precipitation due to heat treatment. In other words, the acrylic structure of the (meth)acrylic polymer is preferably a (meth)acrylic acid structure. The (meth)acrylic polymer may also have a double bond that allows for radical polymerization.

[0051] Furthermore, (meth)acrylic polymers having a styrene structure can be combined with other polymerizable monomers that can copolymerize with them. Examples of copolymerizable monomers include hydroxyl group-containing dibasic acid ester compounds such as monobutyl hydroxyfumarate and monobutyl hydroxyitaconate, various nitrogen-containing compounds such as (meth)acrylamide, diacetone acrylamide, N-methylolacrylamide, or (meth)acrylonitrile; various vinyl esters such as vinyl propionate and vinyl acetate; various silicon-containing polymerizable monomers such as γ-methacryloxypropyltrimethoxysilane and vinyltrimethoxysilane; phosphorus-containing vinyl monomers; various vinyl halides such as vinyl chloride and pyridene chloride; and various conjugated dienes such as butadiene.

[0052] The proportion of (meth)acrylic acid or alkyl (meth)acrylate in a (meth)acrylic polymer having a styrene structure is, for example, 3 mol% or more, preferably 5 to 40 mol%, more preferably 10 to 30 mol%, and even more preferably 15 to 25 mol%, based on the total amount of monomers constituting the (meth)acrylic polymer having a styrene structure. When the proportion of (meth)acrylic acid or alkyl (meth)acrylate is 3 mol% or more, an effect of preventing oligomer precipitation due to heat treatment is exhibited. Furthermore, when it is below the above upper limit, the proportion of styrene structure increases, and the durability of the antistatic performance can be ensured.

[0053] The proportion of styrene and styrene derivatives in a (meth)acrylic polymer having a styrene structure is, for example, 50 to 97 mol%, preferably 60 to 95 mol%, more preferably 70 to 90 mol%, and even more preferably 75 to 85 mol%, based on the total amount of monomers constituting the (meth)acrylic polymer having a styrene structure. If the proportion of styrene and styrene derivatives is above the lower limit, the durability of the antistatic performance is ensured, and if it is below the upper limit, the effect of preventing oligomer precipitation from the base film (polyester film) due to heat treatment is ensured.

[0054] The mechanism by which the precipitation of oligomer components contained in polyester film is suppressed is presumed to be as follows: When polyester film is heated above its glass transition temperature, oligomer components precipitate on its surface. However, by forming a cured resin layer on the polyester film using a resin composition containing a (meth)acrylic polymer with a styrene structure, the aromatic rings contained in the styrene are stacked parallel to the film, creating a structure that prevents the precipitation of oligomer components.

[0055] Compound (A-c) is one or more compounds or derivatives selected from (A-c1) polyglycerin and (A-c2) alkylene oxide adducts to polyglycerin. By including compound (A-c), the transparency of the coating can be maintained by suppressing the occurrence of cracks in the resin layer (A) when the film is stretched. Polyglycerin is a compound represented by the following general formula (3).

[0056]

[0057] In the above formula, n is 2 or greater, and in the present invention, n in the formula is usually in the range of 2 to 20, preferably 3 to 15, and more preferably 3 to 12.

[0058] An alkylene oxide adduct to polyglycerin is a structure having been obtained by addition polymerization of alkylene oxide to the hydroxyl groups of polyglycerin represented by general formula (3). Here, the structure of the alkylene oxide to be added may differ for each hydroxyl group of the polyglycerin skeleton. Furthermore, it is sufficient that the alkylene oxide is added to at least one hydroxyl group in the molecule; it is not necessary for all hydroxyl groups to be accompanied by alkylene oxide or a derivative thereof.

[0059] Preferred alkylene oxides to be added to polyglycerin are ethylene oxide or propylene oxide. If the alkylene chain of the alkylene oxide becomes too long, the hydrophobicity increases, the dispersibility in the coating solution deteriorates, and the antistatic properties and transparency of the cured resin layer tend to worsen. Ethylene oxide is particularly preferred. Furthermore, the number of added atoms is preferably in the range of 200 to 2000 in terms of the number average molecular weight of the final compound, more preferably in the range of 300 to 1000, and even more preferably in the range of 400 to 900. The above polyglycerin, or the alkylene oxide adduct to polyglycerin, may be used individually or in combination of two or more types.

[0060] As described above, the resin layer (A) in the present invention contains an antistatic agent and, if necessary, is formed from a resin composition containing compound (A-b) and compound (A-c) to exhibit good antistatic properties. Furthermore, by including a mold release agent, the load applied to the surface of the resin layer (A) can be reduced due to the slippery effect of the mold release agent.

[0061] There are no particular restrictions on the release agent, and conventionally known release agents can be used. Examples include waxes, long-chain alkyl group-containing compounds, fluorine compounds, and silicone compounds. Among these, it is preferable that the release agent be at least one of waxes and long-chain alkyl group-containing compounds, and more preferably waxes from the viewpoint of achieving both antistatic properties and lubricity. In this composition, the release agent may be used alone or two or more may be used in combination.

[0062] (Waxes) The above waxes include natural waxes, synthetic waxes, and modified waxes. Natural waxes include plant-based waxes, animal-based waxes, mineral waxes, and petroleum waxes. Plant-based waxes include candelilla wax, carnauba wax, rice wax, wood wax, and jojoba oil. Animal-based waxes include beeswax, lanolin, and whale wax. Mineral waxes include montan wax, ozokerite, and ceresin. Petroleum waxes include paraffin wax, microcrystalline wax, and petrolatum.

[0063] Examples of synthetic waxes include synthetic hydrocarbons, modified waxes, hydrogenated waxes, fatty acids, acid amides, amines, imides, ester waxes, and ketones. Other examples of synthetic waxes include Fischer-Tropsch wax (also known as sazole wax) and polyethylene wax. In addition, low molecular weight polymers (specifically polymers with a number average molecular weight of 500 to 20,000) such as polypropylene, ethylene-acrylic acid copolymers, polyethylene glycol, polypropylene glycol, and block or graft conjugates of polyethylene glycol and polypropylene glycol are also available.

[0064] Examples of modified waxes include montan wax derivatives, paraffin wax derivatives, and microcrystalline wax derivatives. Here, a derivative refers to a compound obtained by purification, oxidation, esterification, saponification, or a combination thereof. Examples of hydrogenated waxes include hydrogenated castor oil and hydrogenated castor oil derivatives.

[0065] In particular, synthetic waxes are preferred as the mold release agent, polyethylene wax is more preferred among them, and oxidized polyethylene wax is even more preferred. When this composition is diluted with a solvent such as water to make a coating solution, the wax may be dispersed with a surfactant or the like to form a wax emulsion, which may then be incorporated into the coating solution.

[0066] The number-average molecular weight of synthetic waxes is typically in the range of 500 to 30,000, preferably 1,000 to 15,000, and more preferably 2,000 to 8,000, from the viewpoint of handling ease. The number-average molecular weight is a polystyrene equivalent value measured using gel permeation chromatography (GPC).

[0067] Furthermore, considering that heating is required for crosslinking and other purposes when forming the resin layer (A), the melting point or softening point of the wax is preferably 80°C or higher, and more preferably 110°C or higher. On the other hand, from the viewpoint of controlling the phase separation performance after heat treatment, it is preferably 200°C or lower, more preferably 170°C or lower, and even more preferably 150°C or lower. The melting point of the wax can be measured using a differential scanning calorimeter (DSC).

[0068] (Long-chain alkyl group-containing compounds) Long-chain alkyl group-containing compounds are compounds having a linear or branched alkyl group with 6 or more carbon atoms, preferably 8 or more, and more preferably 12 or more. Examples of alkyl groups include alkyl groups with about 6 to 30 carbon atoms, such as hexyl, octyl, decyl, lauryl, octadecyl, and behenyl groups. Examples of compounds having alkyl groups include various long-chain alkyl group-containing polymer compounds, long-chain alkyl group-containing amine compounds, long-chain alkyl group-containing ether compounds, and long-chain alkyl group-containing quaternary ammonium salts. When considering heat resistance, polymer compounds are preferred, and polymer compounds having long-chain alkyl groups as side chains are more preferred.

[0069] Polymer compounds having long-chain alkyl groups as side chains can be obtained by reacting a polymer having a reactive group with a compound having an alkyl group that can react with the reactive group. Examples of the reactive group include hydroxyl groups, amino groups, carboxyl groups, and acid anhydrides. Examples of compounds having these reactive groups include polyvinyl alcohol, polyethyleneimine, polyethyleneamine, reactive group-containing polyester resin, and reactive group-containing poly(meth)acrylic resin. Among these, polyvinyl alcohol is preferred considering ease of handling. The degree of polymerization of the polyvinyl alcohol used is not particularly limited, but is usually 100 or more, preferably in the range of 300 to 40000. The degree of saponification of the polyvinyl alcohol is not particularly limited, but is usually 70 mol% or more, preferably in the range of 70 to 99.9 mol%, more preferably 80 to 97 mol%, and even more preferably 86 to 95 mol%.

[0070] Compounds having alkyl groups that can react with the above-mentioned reactive groups include, for example, long-chain alkyl-containing isocyanates such as hexyl isocyanate, octyl isocyanate, decyl isocyanate, lauryl isocyanate, octadecyl isocyanate, and behenyl isocyanate; long-chain alkyl-containing acid chlorides such as hexanoyl chloride, octanoyl chloride, decanoyl chloride, lauroyl chloride, octadecanoyl chloride, and behenoyl chloride; long-chain alkyl-containing amines; and long-chain alkyl-containing alcohols. Among these, long-chain alkyl-containing isocyanates are preferred considering ease of handling, and octadecyl isocyanate is particularly preferred.

[0071] Furthermore, polymer compounds having long-chain alkyl groups as side chains can also be obtained by polymerization of long-chain alkyl (meth)acrylates or by copolymerization of long-chain alkyl (meth)acrylates with other vinyl group-containing monomers. Examples of long-chain alkyl (meth)acrylates include hexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, octadecyl (meth)acrylate, and behenyl (meth)acrylate.

[0072] (Fluorine Compounds) Fluorine compounds are compounds that contain fluorine atoms. Organic fluorine compounds are preferably used in terms of the appearance of the coating by in-line coating, and examples include perfluoroalkyl group-containing compounds, polymers of olefin compounds containing fluorine atoms, and aromatic fluorine compounds such as fluorobenzene. From the viewpoint of being able to effectively obtain moderate surface irregularity formation performance through phase separation with a small content, compounds having a perfluoroalkyl group are preferred. Furthermore, compounds containing long-chain alkyl compounds as described above can also be used as fluorine compounds.

[0073] Compounds containing perfluoroalkyl groups include, for example, perfluoroalkyl group-containing (meth)acrylates and their polymers, such as perfluoroalkyl (meth)acrylate, perfluoroalkyl methyl (meth)acrylate, 2-perfluoroalkyl ethyl (meth)acrylate, 3-perfluoroalkyl propyl (meth)acrylate, 3-perfluoroalkyl-1-methylpropyl (meth)acrylate, and 3-perfluoroalkyl-2-propenyl (meth)acrylate; and perfluoroalkyl group-containing vinyl ethers and their polymers, such as perfluoroalkyl methyl vinyl ether, 2-perfluoroalkyl ethyl vinyl ether, 3-perfluoropropyl vinyl ether, 3-perfluoroalkyl-1-methylpropyl vinyl ether, and 3-perfluoroalkyl-2-propenyl vinyl ether. Polymers are preferable when considering heat resistance. Polymers may consist of a single compound or a polymer of multiple compounds. Furthermore, from the viewpoint of effectively imparting lubricity with a small content, the perfluoroalkyl group preferably has 3 to 11 carbon atoms. Furthermore, polymers with compounds containing long-chain alkyl compounds as described above may also be used, and polymers with vinyl chloride are also preferably used from the viewpoint of adhesion to the polyester film base material.

[0074] (Silicone Compounds) Silicone compounds are compounds that have a silicone structure within their molecules, and examples include silicone emulsions, acrylic grafted silicones, silicone grafted acrylics, amino-modified silicones, perfluoroalkyl-modified silicones, alkyl-modified silicones, etc. When considering heat resistance, it is preferable to include a curable silicone resin. As for the type of curable silicone resin, any curing reaction type such as addition type, condensation type, ultraviolet curing type, or electron beam curing type can be used.

[0075] The above resin composition may contain a crosslinking agent for the purpose of improving the durability of the resin layer (A), particularly the durability of its antistatic properties. Various known crosslinking agents can be used, such as melamine compounds, epoxy compounds, isocyanate compounds, carbodiimide compounds, oxazoline compounds, and silane coupling compounds. Among these, melamine compounds, epoxy compounds, isocyanate compounds, and carbodiimide compounds are preferred in terms of suppressing the decrease in antistatic properties after exposure to air, and melamine compounds are more preferred from the viewpoint of further improving the durability of the resin layer (A).

[0076] Melamine compounds are compounds that have a melamine skeleton in their composition. For example, alkylolated melamine derivatives, compounds obtained by reacting alkylolated melamine derivatives with alcohol to partially or completely etherify them, and mixtures thereof can be used. Suitable alcohols for etherification include methyl alcohol, ethyl alcohol, isopropyl alcohol, n-butanol, and isobutanol. The melamine compound may be a monomer, a polymer of two or more units, or a mixture thereof. Furthermore, compounds in which urea or the like is co-condensed with a portion of the melamine can also be used, and catalysts can be used to increase the reactivity of the melamine compound.

[0077] In forming the resin layer (A), it is also possible to include various conventionally known polymers, such as polyester resin, acrylic resin, or urethane resin, as a binder to improve the appearance and transparency of the coating.

[0078] Furthermore, within the scope that does not impair the spirit of the present invention, the resin layer (A) may contain particles for the purpose of improving blocking properties, slipperiness, etc.

[0079] When the resin composition forming the resin layer (A) further contains compound (A-b) and compound (A-c), the content ratio of each component is preferably as follows.

[0080] The proportion of compound (A-a), which is an antistatic agent, in the total nonvolatile components of the resin composition of the resin layer (A) is preferably 2 to 30% by mass, more preferably 3 to 15% by mass, and even more preferably 5 to 12% by mass. When the proportion of compound (A-a) is below the upper limit, the strength and transparency of the resin layer (A) tend to be good. On the other hand, when the proportion of compound (A-a) is above the lower limit, sufficient antistatic performance can be obtained, and the decrease in antistatic properties tends to be suppressed.

[0081] The proportion of compound (A-b) in the total nonvolatile components of the resin composition of the resin layer (A) is preferably 5 to 80% by mass, more preferably 10 to 50% by mass, and even more preferably 15 to 40% by mass. When the ratio of compound (A-b) is below the upper limit, sufficient antistatic properties are obtained, and the coating appearance tends to be good. On the other hand, when the ratio of compound (A-b) is above the lower limit, oligomer precipitation can be sufficiently suppressed, sufficient film-forming properties can be ensured, and a uniform coating film can be obtained.

[0082] The proportion of compound (A-c) in the resin composition of the resin layer (A) is preferably 10 to 85% by mass, more preferably 40 to 70% by mass, and even more preferably 45 to 65% by mass. When the ratio of compound (A-c) is below the upper limit, the antistatic properties and film-forming properties tend to be sufficient. On the other hand, when the ratio of compound (A-c) is above the lower limit, the transparency of the resin layer (A) tends to be good.

[0083] When a release agent is contained in the resin layer (A), it is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 6% by mass or less, as a percentage of the total nonvolatile components in the resin composition. On the other hand, the lower limit is preferably 1% by mass or more.

[0084] When a crosslinking agent is used in combination with the resin layer (A), it is preferable that the proportion of the crosslinking agent to the total nonvolatile components in the resin composition be 30% by mass or less, more preferably 1 to 25% by mass, and even more preferably 3 to 20% by mass. Using a crosslinking agent within this range provides sufficient antistatic performance, suppresses a decrease in antistatic properties, and tends to improve the strength of the resin layer (A).

[0085] (Method for forming resin layer (A)) The resin layer (A) can be formed by coating a resin composition containing an antistatic agent and, if necessary, the components described above, onto a base film and drying it.

[0086] From the standpoint of handling, working environment, and composition stability, the resin composition is preferably an aqueous solution or aqueous dispersion with water as the main medium.

[0087] Furthermore, to the extent that the spirit of the present invention is not impaired, the resin composition (coating liquid) forming the resin layer (A) may optionally contain an antifoaming agent, a coating property improver, a thickener, inorganic or organic particles, an organic lubricant, an ultraviolet absorber, an antioxidant, a foaming agent, a dye, a pigment, etc.

[0088] The resin layer (A) is formed by coating the base film with a resin composition (coating liquid), and this can be done by in-line coating performed within the film manufacturing process, or by so-called off-line coating, which is applied outside the system onto a film that has already been manufactured.

[0089] Conventional coating methods such as air doctor coating, blade coating, rod coating, bar coating, knife coating, squeeze coating, impregnation coating, reverse roll coating, transfer roll coating, gravure coating, kiss roll coating, cast coating, spray coating, curtain coating, calender coating, and extrusion coating can be used as methods for coating the base film.

[0090] The drying and curing conditions when forming the resin layer (A) on the base film are not particularly limited. For example, when the resin layer (A) is formed by offline coating, it is generally preferable to perform heat treatment at 80 to 200°C for 3 to 40 seconds, preferably at 100 to 180°C for 3 to 40 seconds.

[0091] On the other hand, when a resin layer (A) is provided by inline coating, it is generally preferable to perform heat treatment at 70 to 270°C for 3 to 200 seconds, more preferably at 100 to 250°C for 10 to 100 seconds.

[0092] Furthermore, regardless of whether it is offline coating or in-line coating, heat treatment and active energy ray irradiation such as ultraviolet irradiation may be used in combination as needed. In addition, the polyester film constituting the laminated polyester film in the present invention may be subjected to surface treatment such as corona treatment or plasma treatment in advance.

[0093] (Thickness of resin layer (A)) The thickness of the resin layer (A) is preferably 0.002 μm or more and 1.0 μm or less, more preferably 0.005 μm or more and 0.25 μm or less, and even more preferably 0.02 μm or more and 0.15 μm or less. When the thickness of the resin layer (A) is within the above range, the precipitation of oligomer components can be suppressed and good antistatic properties can be provided.

[0094] <Cured Resin Layer (B)> The cured resin layer (B) of this laminated film (hereinafter sometimes referred to as "this cured resin layer (B)") contains an antistatic agent and is formed by curing a cured resin composition (B') (hereinafter sometimes referred to as "this cured resin composition (B')"), and is laminated on the resin layer (A).

[0095] The surface resistivity of a single layer of the cured resin layer (B) is 1 × 10⁻⁶ １２ It is preferable that the value is Ω / □ or less, and more preferably 1 × 10⁻⁶. １０ Ω / □ or less, particularly preferably 1 × 10 ９ It is less than or equal to Ω / □. In this invention, the surface resistivity of a single layer of the cured resin layer (B) is the value measured by the following method.

[0096] (Method for measuring the surface resistivity of a single layer of cured resin layer (B)) A sample was prepared with a cured resin layer (B) / substrate film (PET) configuration, in which a cured resin layer (B) was provided on one side of a substrate film. After conditioning the sample in a measurement atmosphere of 23°C and 50% RH for 30 minutes, the surface resistivity of the cured resin layer (B) side of the sample was measured using a "4339B High Resistance Meter" manufactured by Resident Technology Co., Ltd. Measurement conditions: Set voltage 0.1V, voltage application time: 15 seconds

[0097] <Cured Resin Composition (B')> (Antistatic Agent) In the present invention, it is preferable that the antistatic agent used in the cured resin layer (B) does not segregate on the surface. Not segregating on the surface means that the antistatic agent is uniformly dispersed throughout the entire layer. As a result, the antistatic agent contained in the resin layer (A) connects with conductive paths, and even when the cured resin layer (B) is provided on the resin layer (A), the excellent antistatic properties of the resin layer (A) can be maintained and exhibited as a laminated film. Furthermore, because the antistatic agent in the resin layer (A) connects with conductive paths, even if the surface resistivity of a single layer of the cured resin layer (B) is higher than that of a single layer of the resin layer (A), the surface resistivity of the cured resin layer (B) laminated on the resin layer (A) as a laminated film can be lowered than the surface resistivity of a single layer of the cured resin layer (B), making it possible to exhibit a low surface resistivity that cannot be achieved with the cured resin layer (B) alone.

[0098] The curable resin layer (B) preferably satisfies the following (1) when the coefficient of variation (CV) of the elemental concentration derived from the antistatic agent, calculated from quantitative mapping of elements derived from the antistatic agent detected by scanning electron microscopy (SEM-EDS) analysis, is (1) In the quantitative mapping, the coefficient of variation of the elemental concentration derived from the antistatic agent in the entire mapping area is CV ＡＬＬ The mapping area was divided into three sections in the thickness direction and five sections in the width direction, for a total of 15 sections, and the coefficient of variation of the elemental concentration derived from the antistatic agent in each section was calculated using CV. ｎ When n = 1 to 15, the overall coefficient of variation CV ＡＬＬ and the maximum value of the coefficient of variation CV in each region ｍａｘ The difference and the overall coefficient of variation CV ＡＬＬThe absolute value of the ratio, and the overall coefficient of variation CV ＡＬＬ and the minimum value CV of the coefficient of variation in each region ｍｉｎ The difference and the overall coefficient of variation CV ＡＬＬ The absolute values ​​of the ratios are both 20% or less. Overall coefficient of variation CV ＡＬＬ and the coefficient of variation CV for each region ｎ The difference and the overall coefficient of variation CV ＡＬ The absolute value of the ratio can be calculated using the following formula: Overall coefficient of variation CV ＡＬＬ and maximum value CV ｍａｘ or minimum value CV ｍｉｎ The difference and the overall coefficient of variation CV ＡＬＬ To find the ratio of and , use CV ｎ Each has a CV ｍａｘ , CV ｍｉｎ This can be calculated by inputting the value of (CV). ＡＬＬ -CV ｎ ) ÷ CV ＡＬＬ ×100 (%)

[0099] The coefficient of variation of the elemental concentration derived from the antistatic agent, calculated from the above quantitative mapping, can be evaluated as the distribution (variation) of the antistatic agent in the cured resin layer (B), and the coefficient of variation for the entire mapping area is CV ＡＬＬ and the coefficient of variation CV for each region ｎ If there is no significant difference, it can be evaluated that there is no abnormally large variation in any particular region and that there is uniformity between regions, that is, that the antistatic agent is uniformly dispersed throughout the cured resin layer (B). Overall coefficient of variation CV ＡＬＬ and the maximum value of the coefficient of variation CV in each region ｍａｘ The difference and the overall coefficient of variation CV ＡＬＬ The absolute value of the ratio, and the overall coefficient of variation CV ＡＬＬ and the minimum value CV of the coefficient of variation in each region ｍｉｎ The difference and the overall coefficient of variation CV ＡＬＬ The absolute value of the ratio of and is set to 20% or less for both, and the coefficient of variation CV of the other 15 divided regions. ｎ Since the amount is less than 20%, it can be evaluated that the antistatic agent is uniformly dispersed throughout the cured resin layer (B).

[0100] The overall coefficient of variation CV ＡＬＬ The coefficient of variation CV for each region ｎThe absolute value of the difference is more preferably 15% or less, even more preferably 12% or less, and particularly preferably 10% or less.

[0101] Furthermore, it is preferable that the average value C of the elemental concentration derived from the antistatic agent in the cured resin layer (B) satisfies the following (2). (2) In the quantitative mapping, the average value C of the elemental concentration derived from the antistatic agent in the entire mapping area ＡＬＬ When the mapping region is divided into three parts in the thickness direction, and the average value of the elemental concentration derived from the antistatic agent in each region is taken as Cn (n=1 to 3), the maximum value C of the average value in each region is... ｍａｘ and minimum value C ｍｉｎ The difference between the difference and the overall average value C ＡＬＬ The ratio is 20% or less. The maximum value C of the average value in each region. ｍａｘ and minimum value C ｍｉｎ The difference between the difference and the overall average value C ＡＬＬ The ratio can be calculated using the following formula: (Maximum average C) ｍａｘ - Minimum average value C ｍｉｎ ) ÷ Overall average C ＡＬＬ ×100 (%)

[0102] The above overall average value C ＡＬＬ If there is no significant difference between the maximum and minimum values ​​of the average values ​​of each region divided in the thickness direction, it can be evaluated that the concentration of the antistatic agent is not unevenly distributed, that is, that the antistatic agent is not unevenly distributed in the cured resin layer (B) but is uniformly dispersed.

[0103] Overall average value C ＡＬＬ The difference between the maximum and minimum mean values ​​for each region is more preferably 15% or less, even more preferably 12% or less, and particularly preferably 10% or less.

[0104] The following describes the specific procedure for performing energy-dispersive X-ray spectroscopy (SEM-EDS) analysis.

[0105] <Preparation of Measurement Sample> [Cross Section Cutting] Equipment: JEOL Ltd. IB-19520CCP Cooled Cross Section Polisher Acceleration Voltage: 4.5kV Gas: Argon, Flow Rate 6.8m³ ３ Cutting time: 3 hours 45 minutes Current value: 106 mA Cutting temperature: -20°C

[0106] A carbon tape containing aluminum (Al) is attached to a copper plate, and a laminated film cut to approximately 2 cm square is attached on top of it. The attached body is cut to approximately 3 mm x 7 mm, set in a sample holder, and then a cross-section is prepared under the above conditions to obtain a sample for measurement.

[0107] [SEM Pretreatment Deposition] Equipment: Hitachi High-Tech Ion Sputter MC1000 Current: 15mA Deposition time: 30 seconds

[0108] Aluminum (Al)-containing carbon tape is attached to the sample stage of the SEM, and the sample prepared in the cross-section is placed on top of it. To prevent static charge buildup on the sample surface, a platinum (Pt) conductive film is sputter-deposited under the above conditions before SEM observation.

[0109] <SEM-EDS Analysis> [Analysis Conditions] Instrument: JEOL Ltd. JSM-IT800 Acceleration Voltage: 5kV Working Distance (WD): 10mm Irradiation Current: 10mA Vacuum Conditions: HV (High Vacuum) Magnification: 80,000x Quantitative Correction: ZAF Correction applied EDS Analysis Mode: Quantitative Mapping

[0110] The sample subjected to the above vapor deposition treatment is subjected to EDS quantitative mapping measurement using a scanning electron microscope (SEM-EDS) under the above measurement conditions. The mapping area is specified so that the layer of elements derived from the antistatic agent is included throughout (area: approximately 500 nm vertically x approximately 1360 nm horizontally), and after measurement in quantitative mapping mode with ZAF correction applied, QuantitativeMAP (quantitative mapping data) is obtained.

[0111] [Selection of elements derived from the antistatic agent] When the measurement sample is analyzed by SEM-EDS, a wide variety of elements are identified. Among these, elements derived from the antistatic agent contained in the cured resin layer (B) are selected. For example, nitrogen (N), sulfur (S), phosphorus (P), tin (Sn), etc. may be detected, but if the antistatic agent is an electronically conductive compound, it is preferable to select tin (Sn).

[0112] [Distribution of antistatic agent: Mean value and coefficient of variation (CV) of elemental concentration derived from antistatic agent (distribution of antistatic agent)] The mapping area of ​​the obtained quantitative map is divided into 3 parts in the thickness direction and 5 parts in the width direction, for a total of 15 parts. The mean value and standard deviation of the elemental concentration (wt%) derived from the antistatic agent in the entire mapping area and in each area are calculated, and the coefficient of variation is calculated using the following formula: Coefficient of variation (CV (%)) = (Standard deviation ÷ Mean value) × 100

[0113] Electronically conductive compounds are preferred as antistatic agents for the cured resin layer (B). Specific examples of electronically conductive compounds preferred for use in the cured resin layer (B) include tin oxide (TiO2). ２ Examples of electronically conductive metal oxides include phosphorus-doped tin oxide (PTO), antimond-doped tin oxide (ATO), and tin-doped indium oxide (ITO). Among these, phosphorus-doped tin oxide (PTO) is more preferable in terms of conductivity and environmental considerations. One or more of these electronically conductive compounds may be used.

[0114] The shape of the antistatic agent used in the cured resin layer (B) is not particularly limited, but it is preferably particulate. Examples of particle shapes include spherical, lumpy, rod-shaped, and flattened. Furthermore, from the viewpoint of antistatic properties, the average particle size is preferably 0.01 to 5 μm, more preferably 0.03 to 3 μm, and particularly preferably 0.05 to 1.5 μm. When the average particle size is within the above range, the conductive paths with the antistatic agent contained in the resin layer (A) are efficiently connected, and the laminated film can exhibit excellent antistatic properties.

[0115] The content of the antistatic agent in the cured resin layer (B) is preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 60% by mass or less, and especially preferably 30% by mass or less. By keeping the antistatic agent content below the above upper limit, it is easy to obtain a cured resin layer (B) with sufficient transparency and antistatic performance. Alternatively, the content of the antistatic agent in the cured resin layer (B) is preferably 1% by mass or more, even more preferably 2% by mass or more, more preferably 3% by mass, and especially preferably 5% by mass. By keeping the antistatic agent content above the above lower limit, it is possible to obtain a cured resin layer (B) that exhibits excellent antistatic properties and satisfies practical abrasion resistance, while also keeping costs down.

[0116] (Curing component) As the compound contained in this curing resin composition (B'), conventionally known materials can be used as the curing component, but it is preferable to use a compound having a (meth)acryloyl group, and in particular (B-a) it is preferable to contain a (meth)acrylate with three or more functionalities.

[0117] In this invention, when the expression "(meth)acrylic" is used, it means either or both "acrylic" and "methacrylic". The same applies to "(meth)acrylate" and "(meth)acryloyl". Furthermore, "(poly)propylene glycol" means either or both "propylene glycol" and "polypropylene glycol". The same applies to "(poly)ethylene glycol".

[0118] ((B-a) Trifunctional or higher (meth)acrylate) (B-a) Trifunctional or higher (meth)acrylate is any compound having three or more (meth)acryloyl groups in one molecule, and is not particularly limited. Furthermore, (B-a) Trifunctional or higher (meth)acrylate may be a monomer or an oligomer. In the present invention, it is preferable to use a trifunctional or higher urethane (meth)acrylate (B-a-u) in terms of balancing repeated bending characteristics and abrasion resistance, and adjusting the refractive index.

[0119] Examples of monomer (meth)acrylates (B-a-m) with three or more functionalities include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tri(meth)acryloyloxyethoxytrimethylolpropane, and glycerin polyglycidyl ether. Examples include poly(meth)acrylate, isocyanurate ethylene oxide-modified poly(meth)acrylate, ethylene oxide-modified dipentaerythritol penta(meth)acrylate, ethylene oxide-modified dipentaerythritol hexa(meth)acrylate, ethylene oxide-modified pentaerythritol tri(meth)acrylate, ethylene oxide-modified pentaerythritol tetra(meth)acrylate, succinate-modified pentaerythritol poly(meth)acrylate, caprolactone-modified pentaerythritol poly(meth)acrylate, and the like.

[0120] Examples of triplicate or more functional (meth)acrylate (B-a-o) oligomers include triplicate or more functional urethane (meth)acrylate (B-a-u). A triplicate or more functional urethane (meth)acrylate is a compound having three or more (meth)acryloyl groups and one or more urethane bonds. Urethane (meth)acrylate is obtained by reacting an isocyanate compound with a hydroxyl group-containing (meth)acrylate compound, or by reacting an isocyanate compound, a polyol compound, and a hydroxyl group-containing (meth)acrylate compound. Urethane (meth)acrylate can be used alone or in combination of two or more types.

[0121] Examples of trifunctional or higher urethane (meth)acrylates include: (1) the reaction product of a hydroxyl group-containing (meth)acrylate compound (a1) containing one or more (meth)acryloyl groups and a polyvalent isocyanate compound (a2); (2) the reaction product of (a1), (a2) and a polyol compound (a3); and (3) the reaction product of a hydroxyl group-containing (meth)acrylate compound (a4) containing a hydroxyl group and three or more (meth)acryloyl groups and a monoisocyanate compound (a5). Among these, from the viewpoint of stain resistance and abrasion resistance, the reaction product of (1) a hydroxyl group-containing (meth)acrylate compound (a1) and a polyvalent isocyanate compound (a2) is preferred as a trifunctional or higher urethane (meth)acrylate (B-a-u).

[0122] Regarding the hydroxyl group-containing (meth)acrylate compound (a1) containing one or more (meth)acryloyl groups, examples of hydroxyl group-containing (meth)acrylate compounds containing one (meth)acryloyl group include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 6-hydroxyhexyl (meth)acrylate, as well as 2-hydroxyethyl acryloyl phosphate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, caprolactone-modified 2-hydroxyethyl (meth)acrylate, dipropylene glycol (meth)acrylate, fatty acid-modified glycidyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, and polypropylene glycol mono(meth)acrylate. Furthermore, examples of hydroxyl group-containing (meth)acrylate compounds containing two (meth)acryloyl groups include glycerin di(meth)acrylate, 2-hydroxy-3-acryloyl-oxypropyl methacrylate, and pentaerythritol di(meth)acrylate. Hydroxyl group-containing (meth)acrylate compounds (a1) containing one or more (meth)acryloyl groups may be used alone or in combination of two or more.

[0123] Examples of polyvalent isocyanate compounds (a2) include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, phenylene diisocyanate, and naphthalene diisocyanate; pentamethylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate. Examples include aliphatic polyisocyanates such as diisocyanate, lysine diisocyanate, and lysine triisocyanate; alicyclic polyisocyanates such as hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and norbornene diisocyanate; trimer compounds and polymer compounds of these polyisocyanates; allophanate-type polyisocyanates; burette-type polyisocyanates; and water-dispersible polyisocyanates.

[0124] Among these, diisocyanate compounds are preferred in terms of stability during the urethane reaction, with aliphatic diisocyanates such as pentamethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and lysine diisocyanate being preferred; and alicyclic diisocyanates such as hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, and 1,3-bis(isocyanatemethyl)cyclohexane being more preferred. Isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, and norbornene diisocyanate are preferred in terms of low curing shrinkage, and isophorone diisocyanate is particularly preferred in terms of excellent reactivity and versatility. The polyvalent isocyanate compound (a2) may be used alone or in combination of two or more types.

[0125] The polyol compound (a3) ​​is not particularly limited as long as it is a compound containing two or more hydroxyl groups. Examples include aliphatic polyols, alicyclic polyols, polyether polyols, polyester polyols, polycarbonate polyols, polyolefin polyols, polybutadiene polyols, polyisoprene polyols, (meth)acrylic polyols, and the like.

[0126] Examples of aliphatic polyols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, dimethylolpropane, neopentyl glycol, 2,2-diethyl-1,3-propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-tetramethylenediol, 1,3-tetramethylenediol, 2-methyl-1,3-trimethylenediol, 1,5-pentamethylenediol, 1,6 Examples include aliphatic alcohols containing two hydroxyl groups, such as hexamethylenediol, 3-methyl-1,5-pentamethylenediol, 2,4-diethyl-1,5-pentamethylenediol, pentaerythritol diacrylate, 1,9-nonanediol, and 2-methyl-1,8-octanediol; sugar alcohols such as xylitol and sorbitol; and aliphatic alcohols containing three or more hydroxyl groups, such as glycerin, trimethylolpropane, and trimethylolethane.

[0127] Examples of alicyclic polyols include cyclohexanediols such as 1,4-cyclohexanediol and cyclohexyldimethanol, hydrogenated bisphenols such as hydrogenated bisphenol A, and tricyclodecanedimethanol.

[0128] Examples of polyether polyols include alkylene-containing polyether polyols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polybutylene glycol, polypentamethylene glycol, and polyhexamethylene glycol; as well as random copolymers and block copolymers of these polyalkylene glycols.

[0129] Examples of polyester polyols include condensation polymers of polyhydric alcohols and polyhydric carboxylic acids; ring-opening polymers of cyclic esters (lactones); and reaction products of three components: polyhydric alcohols, polyhydric carboxylic acids, and cyclic esters.

[0130] Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,4-tetramethylenediol, 1,3-tetramethylenediol, 2-methyl-1,3-trimethylenediol, 1,5-pentamethylenediol, neopentyl glycol, 1,6-hexamethylenediol, 3-methyl-1,5-pentamethylenediol, 2,4-diethyl-1,5-pentamethylenediol, glycerin, trimethylolpropane, trimethylolethane, cyclohexanediols (such as 1,4-cyclohexanediol), bisphenols (such as bisphenol A), and sugar alcohols (such as xylitol and sorbitol). These may be used individually or in combination of two or more.

[0131] Examples of polycarboxylic acids include aliphatic dicarboxylic acids such as malonic acid, maleic acid, fumaric acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedionic acid; alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid; and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, paraphenylenedicarboxylic acid, and trimellitic acid. These may be used individually or in combination of two or more.

[0132] Examples of cyclic esters include propiolactone, β-methyl-δ-valerolactone, and ε-caprolactone.

[0133] Examples of polycarbonate-based polyols include reaction products of polyhydric alcohols and phosgene, and ring-opening polymers of cyclic carbonates (such as alkylene carbonates). These may be used individually or in combination of two or more.

[0134] The polyhydric alcohols in polycarbonate polyols are the same compounds as those used in polyester polyols. Examples of alkylene carbonates include ethylene carbonate, trimethylene carbonate, tetramethylene carbonate, and hexamethylene carbonate. These may be used individually or in combination of two or more.

[0135] Polycarbonate-based polyols are not particularly limited as long as they are compounds having carbonate bonds within the molecule and hydroxyl groups at the molecular ends. Polycarbonate-based polyols may also have ester bonds in addition to carbonate bonds.

[0136] Examples of polyolefin-based polyols include those having a homopolymer or copolymer of ethylene, propylene, butene, etc. as a saturated hydrocarbon backbone, and having hydroxyl groups at the molecular ends.

[0137] Examples of polybutadiene polyols include those having a butadiene copolymer as the hydrocarbon backbone and having hydroxyl groups at their molecular ends. Polybutadiene polyols may also be hydrogenated polybutadiene polyols in which all or some of the ethylenically unsaturated groups contained in their structure are hydrogenated.

[0138] Examples of polyisoprene polyols include those having an isoprene copolymer as the hydrocarbon backbone and having hydroxyl groups at the molecular ends. Polyisoprene polyols may also be hydrogenated polyisoprene polyols in which all or part of the ethylenically unsaturated groups contained in their structure are hydrogenated.

[0139] Examples of (meth)acrylic polyols include polymers or copolymers of (meth)acrylic acid esters that have at least two hydroxyl groups in the molecule. Examples of such (meth)acrylic acid esters include hydroxyl group-containing (meth)acrylate compounds that contain one of the ethylenically unsaturated groups mentioned above. If necessary, other copolymer monomers can also be copolymerized. Examples of copolymer monomers include acrylic acid esters such as alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, and octadecyl (meth)acrylate, as well as styrene compounds such as methylstyrene. Alternatively, a hydroxyl group-containing (meth)acrylic polyol may be obtained by reacting a (meth)acrylic polymer having a glycidyl group in its side chain with a carboxylic acid such as (meth)acrylic acid, or a hydroxyl group-containing (meth)acrylic polyol may be obtained by reacting a (meth)acrylic polymer having a carboxylic acid in its side chain with a glycidyl group-containing compound.

[0140] Among these, polyester polyols and polyether polyols are preferred, with polyether polyols being particularly preferred in terms of the flexibility of the cured product and compatibility with photopolymerizable compounds, and polytetramethylene glycol being the most preferred. The polyol compound (a3) ​​may be used alone or in combination of two or more.

[0141] The number-average molecular weight of the polyol compound (a3) ​​is preferably 200 to 3,000, more preferably 250 to 2,000, and even more preferably 300 to 1,000. If the number-average molecular weight of the polyol compound (a3) ​​is too small, the crosslinking density tends to increase too much, resulting in poor adhesion to the substrate. If the number-average molecular weight of the polyol compound (a3) ​​is too large, the crystallinity tends to increase, resulting in high viscosity.

[0142] The number-average molecular weight is the number-average molecular weight converted to the molecular weight of standard polystyrene. For example, it can be measured using a high-performance liquid chromatography system (Waters Japan, "Waters 2695 (main unit)" and "Waters 2414 (detector)") with three Shodex GPC KF-806L columns connected in series (exclusion limit molecular weight: 2 × 10⁷, separation range: 100 to 2 × 10⁷, theoretical plates: 10,000 plates / column, packing material: styrene-divinylbenzene copolymer, packing particle size: 10 μm).

[0143] Examples of hydroxyl group-containing (meth)acrylate compounds (a4) containing three or more (meth)acryloyl groups include pentaerythritol tri(meth)acrylate, caprolactone-modified pentaerythritol tri(meth)acrylate, ethylene oxide-modified pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, caprolactone-modified dipentaerythritol penta(meth)acrylate, and ethylene oxide-modified dipentaerythritol penta(meth)acrylate. Among these, dipentaerythritol penta(meth)acrylate and pentaerythritol tri(meth)acrylate are preferred.

[0144] Examples of monoisocyanate compounds (a5) include monoisocyanates such as butane isocyanate, 3-chlorobenzene isocyanate, cyclohexane isocyanate, and 3-isopropenoyl-α,α-dimethylbenzyl isocyanate.

[0145] Three- or more functional urethane (meth)acrylates (B-a-u) can be synthesized according to known methods. For example, the reaction product of a hydroxyl group-containing (meth)acrylate compound (a1) and a polyvalent isocyanate compound (a2) can be synthesized according to the method described in paragraphs

[0036] to

[0042] of Japanese Patent Application Publication No. 2020-152786.

[0146] The weight-average molecular weight of the trifunctional or more urethane (meth)acrylate (B-a-u) that can be used in the present invention is preferably 1,000 to 60,000, more preferably 1,500 to 50,000, and even more preferably 1,800 to 30,000. If the weight-average molecular weight is above the lower limit, the curing shrinkage of the cured product will not be large, and if it is below the upper limit, the viscosity will be kept low, making it easy to handle.

[0147] The weight-average molecular weight is the weight-average molecular weight converted to the standard polystyrene molecular weight, and can be measured using high-performance liquid chromatography (Waters Japan, "Waters 2695 (main unit)" and "Waters 2414 (detector)") with three Shodex GPC KF-806L columns (exclusion limit molecular weight: 2 × 10⁷, separation range: 100 to 2 × 10⁷, theoretical plates: 10,000 plates / column, packing material: styrene-divinylbenzene copolymer, packing particle size: 10 μm) connected in series.

[0148] The viscosity of a trifunctional or more urethane (meth)acrylate (B-a-u) at 60°C is preferably 500 to 100,000 mPa·s, more preferably 800 to 50,000 mPa·s, and even more preferably 1,000 to 35,000 mPa·s. A viscosity within this range provides good workability. The viscosity values ​​were measured using an E-type viscometer.

[0149] The curable resin composition (B') according to the present invention may contain (meth)acrylate compounds in addition to the trifunctional or more functional (meth)acrylate (B-a). Examples of such (meth)acrylate compounds include monofunctional (meth)acrylates and their derivatives, and difunctional (meth)acrylates and their derivatives. The content of these (meth)acrylate compounds other than the trifunctional or more functional (meth)acrylate (B-a) is usually 20 parts by mass or less, preferably 10 parts by mass or less, per 100 parts by mass of the trifunctional or more functional (meth)acrylate (B-a).

[0150] Examples of monofunctional (meth)acrylates and their derivatives include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, iso-propyl (meth)acrylate, n-butyl (meth)acrylate, iso-butyl (meth)acrylate, sec-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-decyl (meth)acrylate. Lauryl (meth)acrylate, n-tridecyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, ethoxyethyl (meth)acrylate, ethyl carbitol (meth)acrylate, butoxyethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and their cationization agents. Examples include diethylaminoethyl (meth)acrylate and its modified forms with cationizing agents, cyanoethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate and other alkoxy polyalkylene glycol (meth)acrylates, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxyethyl phthalate, (meth)acrylic acid, 2-(meth)acryloyloxyethyl phthalate, 2-(meth)acryloyloxyethyl hexahydrophthalate, 2-(meth)acryloylpropyl phthalate, (meth)acryloyloxyethyl succinate, 2-isocyanate ethyl (meth)acrylate, and the like.

[0151] Examples of difunctional (meth)acrylates and their derivatives include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, ethoxylated di(meth)acrylate, propoxylated hexanediol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate, and other difunctional (meth)acrylates, as well as difunctional urethane (meth)acrylates, difunctional epoxy acrylates, and difunctional polyester acrylates.

[0152] (Fine particles) The curable resin composition (B') may also contain fine particles to enhance the surface hardness (scratch resistance) of the curable resin layer (B). Examples of fine particles include inorganic particles such as silica, calcium carbonate, magnesium carbonate, barium carbonate, calcium sulfate, calcium phosphate, magnesium phosphate, kaolin, aluminum oxide (alumina), and titanium oxide; and organic particles such as acrylic resin, styrene resin, urea resin, phenolic resin, epoxy resin, and benzoguanamine resin. Among these, inorganic particles are preferred, and aluminum oxide is particularly preferred because it is easy to adjust the scratch resistance. Furthermore, the average particle size of the fine particles is preferably 25 nm or less, more preferably 20 nm or less, and even more preferably 15 nm or less, from the viewpoint of transparency. Furthermore, there is no particular limit to the lower limit of the average particle size, but it is preferably 5 nm or more, and even more preferably 10 nm or more, from the viewpoint of dispersibility. The content of fine particles in the curable resin composition (B') is preferably 5 to 40% by mass, more preferably 10 to 35% by mass, and even more preferably 15 to 30% by mass, relative to the total amount (solid content) of the compound having a (meth)acryloyl group and the fine particles. By setting the content of fine particles within the above range, it is possible to achieve both excellent abrasion resistance and antistatic properties of the laminated film, while also satisfying transparency requirements.

[0153] (Solvent) The curable resin composition (B') may be diluted with a solvent to form a coating solution. The curable resin composition (B') may be applied as a liquid coating solution onto the resin layer (A), dried, and cured to form a cured resin layer (B). Each component of the curable resin composition (B') may be dissolved in the solvent or dispersed in the solvent. An organic solvent is preferred as the solvent. Specific examples of organic solvents include, for example, aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone (MEK), acetone, methyl isobutyl ketone (MIBK), cyclohexanone, and diisobutyl ketone; ether solvents such as diethyl ether, isopropyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether (PGM), anisole, and phenethole; ester solvents such as ethyl acetate, butyl acetate, isopropyl acetate, and ethylene glycol diacetate; amide solvents such as dimethylformamide, diethylformamide, dimethylacetamide, and N-methylpyrrolidone; cellosolve solvents such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve; alcohol solvents such as methanol, ethanol, propanol, isopropanol, and butanol; and halogen solvents such as dichloromethane and chloroform. These organic solvents may be used individually or in combination of two or more. Of these organic solvents, ester-based solvents, ether-based solvents, alcohol-based solvents, and ketone-based solvents are preferably used.

[0154] There are no particular restrictions on the amount of organic solvent used, and it is determined appropriately considering the coatability of the prepared curable resin composition, the viscosity and surface tension of the liquid, the compatibility of the solids, etc. The curable resin composition (B') is prepared using the aforementioned solvent as a coating solution, preferably with a solids content concentration of 15 to 80% by mass, more preferably 20 to 70% by mass. In curable resin composition (B'), "solids" refers to the components excluding the volatile solvent component, and includes not only solid components but also semi-solid and viscous liquid substances.

[0155] (Other components) The curable resin composition (B') may contain various additives as needed, within the limits that do not impair the spirit of the present invention. Examples of additives that may be used include photoinitiators, light stabilizers, antioxidants, antistatic agents, flame retardants, leveling agents, dispersants, thixotropy-imparting agents (thickening agents), and defoaming agents. Examples of leveling agents include fluorine-based leveling agents, silicone-based leveling agents, and acrylic-based leveling agents. Among these, fluorine-based leveling agents are preferred as leveling agents because they provide the hard coat layer with functions such as repelling water and oil and preventing the adhesion of dirt such as fingerprints.

[0156] (Photoinitiator) When the curable resin composition (B') is a photocurable resin composition, it is preferable to include a photoinitiator in order to improve curability. The photoinitiator is a photopolymerization initiator, and known ones can be used. Examples of photopolymerization initiators include photoradical generators and photoacid generators.

[0157] Among the photopolymerization initiators that can be used in the curable resin composition (B'), the photoradical generators include, for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and other benzoin and its alkyl ethers; acetophenone, 2,2-dimethoxy-2-phenylacetophenone [for example, trade name "Omnirad® 651", manufactured by IGM RESINS], 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone [for example, trade name "Omnirad® 184", manufactured by IGM RESINS], 2-hydroxy-2-methyl-1-phenylpropan-1-one [for example, trade name "Omnirad® 1173", manufactured by IGM [Manufactured by RESINS], 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one [e.g., trade name "Omnirad® 127, manufactured by IGM RESINS"], 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one [e.g., trade name "Omnirad® 2959", manufactured by IGM RESINS], 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one [e.g., trade name "Omnirad® 907", manufactured by IGM RESINS Examples include alkylphenones such as 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone [manufactured by IGM RESINS], phosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide [e.g., trade name "Omnirad® TPO", manufactured by IGM RESINS], bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide [e.g., trade name "Omnirad® 819", manufactured by IGM RESINS], anthraquinones such as 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, and 2-amylanthraquinone; benzophenones and their various derivatives; and formic acid derivatives such as methyl benzoylformate and ethyl benzoylformate.These can be used individually or in combination of two or more types.

[0158] Among these photoradical generators, alkylphenones, phosphine oxides, and formic acid derivatives are preferred from the viewpoint of the light resistance of the cured product, and more preferably 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and methyl benzoylformate are particularly preferred, and especially preferred are 1-hydroxycyclohexylphenyl ketone and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one.

[0159] While known photoacid generators can be used, diaryliodonium salts and triarylsulfonium salts are preferred from the viewpoint of curability and acid generation efficiency. For example, di(alkyl-substituted)phenyliodonium anionic salts (specifically PF ６ Salt SbF ５ Examples include salts, tetrakis(perfluorophenyl)borate salts, etc. Specific examples of anionic salts of (alkyl-substituted) phenyliodonium include dialkylphenyliodonium PF ６ Salt [product name "Omniad® 250", manufactured by IGM RESINS] is particularly preferred. These photoacid generators may be used individually or in combination of two or more.

[0160] The amount of photopolymerization initiator is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and particularly preferably 1 part by mass or more, relative to 100 parts by mass of the total amount of compounds having a (meth)acryloyl group in the curable resin composition (B'), from the viewpoint of improving curability. On the other hand, from the viewpoint of maintaining the stability of the coating solution when the curable resin composition (B') is used as a solution and from the viewpoint of the flatness of the cured coating film, it is preferably 10 parts by mass or less, more preferably 7 parts by mass or less, and particularly preferably 5 parts by mass or less.

[0161] (Viscosity of curable resin composition (B')) The curable resin composition (B') for forming the curable resin layer (B) preferably has a viscosity of 10 to 60 mPa·s at 25°C, as measured with an E-type viscometer, in order to ensure good coatability, and more preferably 30 mPa·s or less, 20 mPa·s or less, and 15 mPa·s or less.

[0162] (Method for forming the cured resin layer (B)) As described above, the cured resin layer (B) can be obtained by applying a curable resin composition to the surface of a resin layer (A) laminated on the surface of a base film, drying it to form a coated layer, and curing the coated layer. As a method for applying the curable resin composition, conventionally known application methods such as air doctor coating, blade coating, rod coating, bar coating, knife coating, squeeze coating, impregnation coating, reverse roll coating, transfer roll coating, gravure coating, kiss roll coating, cast coating, spray coating, curtain coating, calendr coating, and extrusion coating can be used. The drying conditions are not particularly limited and may be carried out at room temperature or by heating, for example, about 25 to 120°C, preferably 50 to 100°C, and more preferably 60 to 90°C. The drying time is not particularly limited as long as the solvent can volatilize sufficiently, for example, about 10 seconds to 30 minutes, preferably about 15 seconds to 10 minutes.

[0163] The curing method for a curable resin composition can be appropriately selected according to the curing mechanism of the curable resin composition. If the curable resin composition is a thermosetting resin composition, it can be cured by heating. If it is a photocurable resin composition, it can be cured by irradiation with energy rays. In the laminated film of the present invention, the active energy rays that can be used to cure the photocurable resin composition include ultraviolet rays, electron beams, X-rays, infrared rays, and visible light. Of these active energy rays, ultraviolet rays and electron beams are preferred from the viewpoint of curability and prevention of resin degradation.

[0164] From the viewpoint of molding time and productivity, and from the viewpoint of preventing thermal shrinkage and thermal degradation of each component due to heating, it is preferable to cure the curable resin composition by energy ray irradiation. Energy ray irradiation may be performed from either side, from the base film side, or from the opposite side of the base film. When curing the curable resin composition by ultraviolet irradiation when manufacturing the laminated film of the present invention, various ultraviolet irradiation devices can be used, and as light sources, xenon lamps, high-pressure mercury lamps, metal halide lamps, LED-UV lamps, etc., can be used. Ultraviolet irradiation amount (unit: mJ / cm) ２ ) is typically 50 to 3,000 mJ / cm². ２ Therefore, from the viewpoint of curability of the curable resin composition and flexibility of the cured product (cured film), it is preferably 100 to 1,000 mJ / cm². ２ Therefore, from the viewpoint of the flatness of the laminated film, it is more preferably 100 to 500 mJ / cm². ２ This range is appropriately determined according to the reaction rate of (meth)acryloyl groups required in each curing step. When used in particularly harsh environments, it is preferable to adjust the surface hardness of the cured product of the curable resin composition by increasing the amount of ultraviolet irradiation.

[0165] Furthermore, when manufacturing the laminated film of the present invention, various electron beam irradiation devices can be used when curing the curable resin composition by electron beam irradiation. The electron beam irradiation dose (Mrad) is usually 0.5 to 20 Mrad, and is preferably in the range of 1 to 15 Mrad from the viewpoint of curability of the curable resin composition, flexibility of the cured product, and prevention of damage to the substrate, but is appropriately determined according to the reaction rate of (meth)acryloyl groups required in each curing step.

[0166] (Thickness of the cured resin layer (B)) The thickness of the cured resin layer (B) is preferably 10 μm or less, more preferably 8.0 μm or less, even more preferably 6.0 μm or less, and particularly preferably 5.0 μm or less. When the thickness of the cured resin layer (B) is less than or equal to the above upper limit, excellent antistatic properties and abrasion resistance of the formed laminated film can be ensured. In addition, curling and heat wrinkles can be prevented in the laminated structure having the cured resin layer (B), and good flatness can be ensured. Furthermore, a thickness of 5.0 μm or less is preferable in that it is easy to adjust the balance between the excellent abrasion resistance and antistatic properties of the laminated film. On the other hand, there is no particular limit to the lower limit of the thickness of the cured resin layer (B), but it is preferably 0.5 μm or more, and more preferably 1.0 μm or more, in that it can exhibit practical abrasion resistance and appropriately protect the resin layer (A).

[0167] Furthermore, the ratio of the thickness (t) of the resin layer (A) to the thickness (d) of the cured resin layer (B) is preferably 1 ≤ d / t ≤ 60, more preferably 1.5 ≤ d / t ≤ 30, and even more preferably 2 ≤ d / t ≤ 15, from the viewpoint of the antistatic properties and abrasion resistance of the laminated film.

[0168] <Physical Properties of Laminated Film> (Abrasion Resistance) This laminated film has surface hardness, specifically the scratch resistance of the hardened resin layer (B) surface (with #0000 steel wool and a load of 100g), which can be reduced to prevent scratches even after 10 back-and-forth passes.

[0169] (Antistatic properties) This laminated film has a surface resistivity, specifically the surface resistivity of the cured resin layer (B) side surface, which is 1 × 10 ７ It is less than or equal to Ω / □, preferably 5 × 10６ Ω / □ or less, particularly preferably 2.5×10 ６ Ω / □ or less, particularly preferably 1.5×10 ６ Ω / □ or less. There is no particular lower limit for the surface resistivity, but considering the cost of the antistatic agent, it is preferably 1×10 ４ Ω / □ or more.

[0170] (Antistatic property of each layer) The surface resistivity of the cured resin layer (B) of this laminated film is higher than that of the resin layer (A). That is, in the surface resistivity measured using a sample having a structure of resin layer (A) / base film and cured resin layer (B) / base film, where the resin layer (A) and the cured resin layer (B) are provided on the base film respectively, even if the surface resistivity of the cured resin layer (B) is higher than that of the resin layer (A), the surface resistivity of the surface of the cured resin layer (B) when formed into a laminated film becomes as low as that of the resin layer (A), and it is possible to achieve both excellent antistatic property and practical scratch resistance as a laminated film.

[0171] It is preferable that the surface resistivity of the single layer of the resin layer (A) is as low as possible, but it is preferably 1×10 ７ Ω / □ or less, more preferably 5×10 ６ Ω / □ or less, particularly preferably 1×10 ６ Ω / □ or less.

[0172] It is preferable that the surface resistivity of the single layer of the cured resin layer (B) is low, but it is preferably 1×10 １２ Ω / □ or less, more preferably 1×10 １０ Ω / □ or less, particularly preferably 1×10 ９ Ω / □ or less.

[0173] The difference between the surface resistivity of the single layer of the cured resin layer (B) and the surface resistivity of the single layer of the resin layer (A) is preferably greater than 0 and less than 1×10 １２ Ω / □, particularly preferably greater than 1×10 ５ Ω / □ and less than ^{-1}×10 １０ Ω / □.

[0174] Furthermore, the ratio of the surface resistivity of a single layer of the cured resin layer (B) to the surface resistivity of a single layer of resin layer (A) (surface resistivity of a single layer of cured resin layer (B) / surface resistivity of a single layer of resin layer (A)) is greater than 0, which is 1 × 10⁻⁶. １２ Smaller is preferable. The lower limit is 1 × 10⁻⁶. ２ Larger is preferable, 1 × 10 ５ Larger is even preferable. The upper limit is 1 x 10⁻⁶. １０ Smaller is preferable.

[0175] <Characteristics and Applications of the Laminated Film> This laminated film possesses excellent antistatic properties and practical scratch resistance, making it suitable for use in display components and other applications. For example, it can be suitably used as a protective film for various types of protective films, particularly as a surface protective film for display components. However, the applications of this laminated film are not limited to these uses.

[0176] <<Explanation of Terms>> In this invention, the term "film" includes "sheets," and the term "sheet" includes "film." In this specification, when "X to Y" (where X and Y are any numbers) is written, unless otherwise specified, it includes the meaning of "X or greater and Y or less," as well as "preferably greater than X" or "preferably less than Y." In addition, when "X or greater" (where X is any number) is written, unless otherwise specified, it includes the meaning of "preferably greater than X," and when "Y or less" (where Y is any number) is written, unless otherwise specified, it also includes the meaning of "preferably less than Y."

[0177] The present invention will be specifically described below with reference to examples. However, the present invention is not limited in any way by the following examples. The measurement and evaluation methods used in the present invention are as follows.

[0178] Regarding a sample with the structure of an antistatic cured resin layer (B) / resin layer (A) / substrate film, after conditioning the sample for 30 minutes in a measurement atmosphere of 23°C and 50% RH, the surface resistivity on the cured resin layer (B) side was measured using the "4339B High Resistance Meter" manufactured by Resident Technology Co., Ltd. Measurement conditions: Set voltage 0.1 V, voltage application time: 15 seconds

[0179] (2) Steel wool (SW resistance) test (scratch resistance) Using #0000 steel wool (product name: BONSTAR, manufactured by Nippon Steel Wool Co., Ltd.) of the cured resin layer (B), reciprocating friction was performed while applying a load of 100 g, and the presence or absence of scratches on the surface of the cured resin layer (B) was visually confirmed and judged according to the following criteria. (Judgment criteria) ○: No scratches after 10 reciprocations ×: Scratches after 10 reciprocations

[0180] (3) Film thickness measurement method of the cured resin layer (B) Regarding a sample with the structure of a cured resin layer (B) / resin layer (A) / substrate film, the reflection spectrum in the range of 300 nm to 800 nm was measured from the cured resin layer (B) side using the "Spectrophotometer V-670" manufactured by JASCO Corporation. The general shape of the reflection spectrum was compared with the general shape of the reflection spectrum calculated by the thin film reflectance simulation published on the homepage of Filmmetrics Co., Ltd., and the film thickness of the cured resin layer (B) was estimated.

[0181] (4) Scanning electron microscope (SEM-EDS) analysis [Preparation of measurement sample] Regarding a sample with the structure of a cured resin layer (B) / resin layer (A) / substrate film, a carbon tape containing aluminum (Al) was pasted on a copper plate, and the target film was cut out into a square of about 2 cm on it and pasted. The above adherent was cut out into about 3 mm × 7 mm, set in a sample holder, and then using IB-19520CCP manufactured by JEOL Ltd., with an acceleration voltage of 4.5 kV and an argon gas flow rate of 6.8 m ３The current was set to / s and the cutting temperature to -20°C, and the cross-section was prepared for 3 hours and 45 minutes. Subsequently, an aluminum (Al)-containing carbon tape was attached to the sample stage of the SEM, and the sample from which the cross-section had been prepared was attached on top of it. To prevent static charge on the sample surface, a platinum (Pt) conductive film was sputter-deposited before SEM observation. A Hitachi High-Tech MC1000 ion sputter was used for deposition, with deposition conditions of a current value of 15 mA and a processing time of 30 seconds.

[0182] [SEM-EDS Measurement] The sample subjected to the aforementioned deposition treatment was subjected to EDS quantitative mapping measurement using a JEOL Ltd. JSM-IT800. The measurement conditions were set to an acceleration voltage of 5 kV, an irradiation current of 10 mA, a high vacuum, and a magnification of 8,000 times. The mapping area was specified to include the entire tin (Sn) layer (approximately 500 nm vertically x approximately 1360 nm horizontally), and after performing the measurement in quantitative mapping mode with ZAF correction applied, a Quantitative MAP was acquired.

[0183] The various materials used in the examples and comparative examples were prepared as follows.

[0184] <Polyester Raw Materials> (PET-A) Solid-phase polymerized homopolyethylene terephthalate (using Ti polymerization catalyst) (PET-B) Homopolyethylene terephthalate (using Sb polymerization catalyst) (PET-C) Masterbatch of homopolyethylene terephthalate (using Ti polymerization catalyst) blended with 5% by mass of silica particles with an average particle size of 2.3 μm (PET-D) Masterbatch of homopolyethylene terephthalate (using Sb polymerization catalyst) blended with 2% by mass of silica particles with an average particle size of 2.3 μm

[0185] <Base Film> (Base Film PET1) A mixed raw material prepared by mixing PET-A and PET-C in proportions of 94% by mass and 6% by mass, respectively, was used as the raw material for the outermost layer (surface layer), and PET-A alone was used as the raw material for the intermediate layer. The raw materials for the outermost and intermediate layers were each supplied to two extruders, melted at 285°C, and then co-extruded onto cooling rolls set at 40°C in a layer configuration of two types and three layers (surface layer / intermediate layer / surface layer = discharge volume 1 / 8 / 1) and cooled and solidified to obtain an unstretched sheet. Next, this film was stretched 3.5 times in the longitudinal direction while passing through a group of heated rolls at 85°C to obtain a uniaxially oriented film. The following resin composition (A'1) was applied to one side of this uniaxially oriented film at a coating rate (after drying) of 0.05 g / m². ２ The film was coated, then guided into a tenter stretcher, stretched 4.3 times in the width direction at 100°C, and then heat-treated at 235°C. After that, a 2% relaxation treatment was performed in the width direction to obtain a laminated polyester film with a base film thickness of 50 μm and a resin layer (A) thickness of 0.1 μm. (Layer composition: base film PET1 / resin layer (A1)) The surface resistivity of the resin layer (A) was 6.2 × 10⁻⁶. ５ It was Ω / □.

[0186] <Resin Composition (A'1)> Resin composition (A'1) was prepared by mixing the following compounds. The mixing ratio (mass%) was (A-a1):(A-b1):(A-c1):(A-d1):(A-e1):(A-f1) = 10:13:56.5:4:16:0.5.

[0187] (Compound (A-a)) ・(A-a1): Conductive agent consisting of polyethylenedioxythiophene and polystyrene sulfonic acid (Orgacon ICP1010, manufactured by Agfa-Gevaert) neutralized with concentrated ammonia water to pH = 9; non-volatile component: 1.2% by mass; solvent: water

[0188] (Compound (A-b)) ・(A-b1) Acrylic resin aqueous dispersion polymerized with the following composition: styrene / acrylic acid = 85 / 15 (mass%), non-volatile component: 30% by mass

[0189] (Compound (A-c)) ・(A-c1): Polyglycerin with an average n=4 in the following formula (3)

[0190]

[0191] (Compound (A-d)) ・(A-d1): A wax emulsion prepared by adding 300 g of polyethylene oxide wax with a melting point of 105°C, an acid value of 16 mg KOH / g, a density of 0.93 g / mL, and a number average molecular weight of 5000, 650 g of deionized water, 50 g of decaglycerin monooleate surfactant, and 10 g of 48% potassium hydroxide aqueous solution to a 1.5 L emulsification apparatus equipped with a wax stirrer, thermometer, and temperature controller, then purging with nitrogen, sealing, and stirring at high speed at 150°C for 1 hour, followed by cooling to 130°C, passing through a high-pressure homogenizer under 400 atmospheres, and cooling to 40°C.

[0192] (Crosslinking agent) ・(A-e1): Hexamethoxymethylolmelamine

[0193] (Surfactants) ・(A-f1): A nonionic surfactant having a structure in which the average of m+n in the following formula (5) is 10 and which has polyethylene oxide in its side chains.

[0194]

[0195] <Base Film PET2> A mixed raw material prepared by mixing PET-B at a ratio of 90% by mass and PET-D at a ratio of 10% by mass was used as the raw material for the outermost layer (surface layer), and PET-B alone was used as the raw material for the intermediate layer. These materials were supplied to two extruders, each melted at 285°C, and then co-extruded onto a cooling roll set at 40°C in a layer configuration of two types and three layers (surface layer / intermediate layer / surface layer = discharge volume (mass ratio) of 1 / 8 / 1), and cooled and solidified to obtain an unstretched sheet. Next, using the difference in roll peripheral speed, the film was stretched 3.4 times in the longitudinal direction at a film temperature of 85°C. Then, the coating solution of the easy-adhesion layer composition described below was applied to one side of this longitudinally stretched film, guided into a tenter, stretched 4.3 times in the transverse direction at 110°C, heat-treated at 235°C, and then relaxed by 2% in the transverse direction to obtain an easy-adhesion layer-attached polyester film with a base film thickness of 50 μm and an easy-adhesion layer thickness (after drying) of 0.1 μm. (Layer composition: Base film PET2 / Easy-adhesion layer)

[0196] [Easy-to-adhere layer composition] An easy-to-adhere layer composition was prepared by mixing the following compounds in a ratio of X1:X2:Y1:Y2:Y3 = 60:10:10:10:10 (mass %) of solids. <Binder Resin> (X1): Aqueous dispersion of polyester resin having a condensed polycyclic structure copolymerized with the following composition: monomer composition: (acid component) 2,6-naphthalenedicarboxylic acid / 5-sodium sulfisoisophthalic acid / / (diol component) ethylene glycol / diethylene glycol = 92 / 8 / / 80 / 20 (mol%) (X2): Emulsifying polymer of acrylic resin aqueous dispersion polymerized with the following composition: ethyl acrylate / n-butyl acrylate / methyl methacrylate / N-methylolacrylamide / acrylic acid = 65 / 21 / 10 / 2 / 2 (mass%) (emulsifier: anionic surfactant) <Crossing Agent> (Y1): Hexamethoxymethylolated melamine (Y2): Water-soluble polyglycerol polyglycidyl ether (Y3): Oxazoline group-containing acrylic polymer (Epocross®, oxazoline group amount 4.5 mmol / g, manufactured by Nippon Shokubai Co., Ltd.)

[0197] <Cured resin composition (B')> <Cured resin composition (B'1)> Cured resin composition (B'1) was prepared by diluting 100 parts by mass of a cured resin composition containing phosphorus-doped tin oxide particles (PTO particles) as an antistatic agent with methyl isobutyl ketone (MIBK) to 20 wt%. The surface resistivity of the cured resin layer (B1) obtained by curing the above cured resin composition (B'1) was 1.0 × 10⁻⁶. ８ It was Ω / □.

[0198] <Cured Resin Composition (B'2)> Cured resin composition (B'2) was prepared by adding 100 parts by mass of urethane acrylate (UV1700B, manufactured by Mitsubishi Chemical Corporation) and 5 parts by mass of a photopolymerization initiator (Omnirad 127, manufactured by IGM Resins B.V.). The surface resistivity of the cured resin layer (B2) obtained by curing the above cured resin composition (B'2) could not be measured.

[0199] <Curable resin composition (B'3)> Curable resin composition (B'3) was prepared by adding 100 parts by mass of urethane acrylate (Mitsubishi Chemical Corporation's "UV1700B"), 5 parts by mass of photopolymerization initiator (IGM Resins B.V.'s "Omnirad 127"), and 5 parts by mass of Nippon Chemical Corporation's "Nikka Taibo ST" (quaternary ammonium salt-based antistatic agent). The surface resistivity of the cured resin layer (B3) obtained by curing the above curable resin composition (B'3) was 1.0 × 10⁻⁶. １０ It was Ω / □.

[0200] [Example 1] The cured resin composition (B'1) was applied using a bar coater to cover the resin layer (A) of the base film PET1 so that the coating thickness (after drying) was 0.5 μm. It was heated at 100°C for 30 seconds to dry and obtain the cured resin layer B' (before curing). Integrated light intensity: 400 mJ / cm ２ The cured resin layer B' (before curing) was cured by ultraviolet irradiation under a nitrogen atmosphere to obtain a laminated film consisting of a base film PET1 / resin layer (A1) / cured resin layer (B1). The results of evaluation using the above method are shown in Table 1.

[0201] [Example 2] The same procedure as in Example 1 was followed, except that the coating thickness (after drying) was 1.0 μm, to obtain a laminated film consisting of a base film PET1 / resin layer (A1) / cured resin layer (B1). The results of evaluation using the above method are shown in Table 1.

[0202] [Comparative Example 1] A laminated film was obtained by manufacturing in the same manner as in Example 1, except that a cured resin layer (B) was not provided. The results of evaluation in the same manner as in Example 1 are shown in Table 1.

[0203] [Comparative Example 2] A curable resin composition (B'2) that does not contain the above-mentioned antistatic agent was used instead of curable resin composition (B'1) as curable resin composition (B') and was applied so that the coating thickness (after drying) was 0.1 μm. The same procedure as in Example 1 was followed to obtain a laminated film consisting of a base film PET1 / resin layer (A1) / curable resin layer (B2). The results of evaluation using the above method are shown in Table 1.

[0204] [Comparative Example 3] A laminated film was produced in the same manner as in Example 1, except that a curable resin composition (B'2) that does not contain the above-mentioned antistatic agent was used instead of curable resin composition (B'1) as curable resin composition (B'), and a laminated film consisting of a base film PET1 / resin layer (A1) / curable resin layer (B2) was obtained. The results of evaluation using the above method are shown in Table 1.

[0205] [Comparative Example 4] A laminated film was produced in the same manner as in Example 2, except that a curable resin composition (B'2) that does not contain the above-mentioned antistatic agent was used instead of the curable resin composition (B'1) as the curable resin composition (B'), and a laminated film consisting of a base film PET1 / resin layer (A1) / curable resin layer (B2) was obtained. The results of evaluation using the above method are shown in Table 1.

[0206] [Comparative Example 5] A laminated film was manufactured in the same manner as in Example 1, except that a base film PET2 with an easy-adhesion layer without an antistatic agent laminated on it was used instead of a base film PET1 with a resin layer (A) containing an antistatic agent laminated on it, and a curable resin composition (B'3) containing the above-mentioned ionic antistatic agent was used instead of a curable resin composition (B'1) as the curable resin composition (B'), and the film was applied so that the coating thickness (after drying) was 1.0 μm, to obtain a laminated film consisting of a base film PET2 / easy-adhesion layer / curable resin layer (B3). The results of evaluation using the above method are shown in Table 1.

[0207] [Comparative Example 6] A laminated film was produced in the same manner as in Example 1, except that a curable resin composition (B'3) containing the above-mentioned ionic antistatic agent was used instead of the curable resin composition (B'1) as the curable resin composition (B'), and a laminated film consisting of a base film PET1 / resin layer (A1) / curable resin layer (B3) was obtained. The results of evaluation using the above method are shown in Table 1.

[0208] [Comparative Example 7] A laminated film was produced in the same manner as in Example 2, except that a curable resin composition (B'3) containing the above-mentioned ionic antistatic agent was used instead of the curable resin composition (B'1) as the curable resin composition (B'), and a laminated film consisting of a base film PET1 / resin layer (A1) / curable resin layer (B3) was obtained. The results of evaluation using the above method are shown in Table 1.

[0209] <Evaluation Results> The characteristics of each laminated film obtained in the above examples and comparative examples are shown in Table 1 below.

[0210]

[0211] From the results of the above examples and comparative examples, the laminated film of the example that satisfies the configuration of the present invention, having a structure in which a resin layer (A) containing an antistatic agent and a cured resin layer (B) are sequentially laminated on the surface of the base film, and the surface resistivity of the cured resin layer (B) is higher than the surface resistivity of the resin layer (A), has a surface resistivity of 1.0 × 10 ７ It can be seen that it satisfies excellent antistatic properties and practical abrasion resistance, with a coefficient of Ω / □ or less. Furthermore, the laminated film of the example in which the parameters of the cured resin layer (B) satisfy a specific range has a surface resistivity of 1.0 × 10 ７ It has a low surface resistivity of Ω / □ or less, and even when the surface resistivity of a single layer of the cured resin layer (B) is higher than that of a single layer of the resin layer (A), it is clear that it satisfies excellent antistatic properties and practical abrasion resistance.

[0212] In contrast, as shown in Comparative Examples 1 and 2, when the cured resin layer (B) was not provided or when the cured resin layer (B) was very thin, although excellent antistatic properties were obtained, the abrasion resistance was not met. On the other hand, as shown in Comparative Examples 3 and 4, when the cured resin layer (B) was made thicker, practical abrasion resistance could be achieved, but the antistatic properties were greatly reduced. Furthermore, as shown in Comparative Example 5, if there was no resin layer (A) and only the antistatic agent was included in the surface cured resin layer (B), it was difficult to sufficiently reduce the surface resistivity, and it was difficult to achieve very good antistatic properties as a laminated film. Moreover, as shown in Comparative Examples 6 and 7, even if there was a resin layer (A), if the antistatic agent contained in the cured resin layer (B) did not form a conductive path with the antistatic agent in the resin layer (A), antistatic properties could not be obtained, and the surface resistivity of the laminated film was 1.0 × 10⁻⁶. ７ It did not provide the excellent antistatic properties required, such as a value of Ω / □ or less.

[0213] The laminated film of the present invention has excellent antistatic properties and abrasion resistance, making it suitable for use in various protective films. In particular, it can be suitably used in optical applications such as display components.

Claims

1. A laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one side surface of a base film, wherein the surface resistivity of the cured resin layer (B) side of the laminated film is 1 × 10 ７ A laminated film having a resistivity of Ω / □ or less, wherein the resin layer (A) and the cured resin layer (B) contain an antistatic agent, and the surface resistivity of a single layer of the cured resin layer (B) is higher than the surface resistivity of a single layer of the resin layer (A).

2. The laminated film according to claim 1, wherein the antistatic agent contained in the cured resin layer (B) is not segregated.

3. The laminated film according to claim 1, wherein the antistatic agent contained in the cured resin layer (B) is an antistatic agent that can form a conductive path with the antistatic agent contained in the resin layer (A).

4. A laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one surface of a base film, wherein the surface resistivity of the laminated film on the side of the cured resin layer (B) is 1×10 ７ Ω / sq or less, the resin layer (A) and the cured resin layer (B) contain an antistatic agent, and the coefficient of variation (CV) of the element concentration derived from the antistatic agent in the cured resin layer (B), calculated from the quantitative mapping of the elements derived from the antistatic agent detected by scanning electron microscope (SEM-EDS) analysis, satisfies the following (1). (1) In the quantitative mapping, the coefficient of variation of the element concentration derived from the antistatic agent in the entire mapping region is CV ＡＬＬ , the mapping region is divided into 3 parts in the thickness direction and 5 parts in the width direction, for a total of 15 parts, and when the coefficient of variation of the element concentration derived from the antistatic agent in each region is CVn (n = 1 to 15), the overall coefficient of variation CV ＡＬＬ and the maximum value CV of the coefficient of variation of each region ｍａｘ of the difference between, and the overall coefficient of variation CV ＡＬＬ ratio of the absolute value, and the overall coefficient of variation CV ＡＬＬ and the minimum value CV of the coefficient of variation of each region ｍｉｎ of the difference between, and the overall coefficient of variation CV ＡＬＬ ratio of the absolute value of, are each 20% or less.

5. The laminated film according to claim 4, wherein the average value C of the elemental concentration derived from the antistatic agent in the cured resin layer (B) satisfies the following (2): (2) In the quantitative mapping, the average value C of the elemental concentration derived from the antistatic agent in the entire mapping region ＡＬＬ When the mapping region is divided into three parts in the thickness direction, and the average value of the elemental concentration derived from the antistatic agent in each region is taken as Cn (n=1 to 3), the maximum value C of the average value in each region is... ｍａｘ and minimum value C ｍｉｎ The difference between the difference and the overall average value C ＡＬＬ The ratio is 20% or less.

6. A laminated film having a structure in which a resin layer (A) and a cured resin layer (B) are sequentially laminated on at least one side surface of a base film, wherein the surface resistivity of the cured resin layer (B) side of the laminated film is 1 × 10 ７ A laminated film having a static charge of Ω / □ or less, wherein the resin layer (A) and the cured resin layer (B) contain an antistatic agent, the antistatic agent contained in the resin layer (A) contains an electronically conductive compound, and the antistatic agent contained in the cured resin layer (B) contains an electronically conductive metal oxide.

7. The laminated film according to any one of claims 1 to 5, wherein the antistatic agent contained in the cured resin layer (B) contains an electronically conductive compound.

8. The laminated film according to claim 7, wherein the antistatic agent contained in the cured resin layer (B) contains phosphorus-doped tin oxide as an electronically conductive compound.

9. The laminated film according to any one of claims 1 to 5, wherein the antistatic agent contained in the resin layer (A) contains an electronically conductive compound.

10. The laminated film according to claim 9, wherein the antistatic agent contained in the resin layer (A) contains a polythiophene compound as an electronically conductive compound.

11. A laminated film according to any one of claims 1 to 6, wherein the antistatic agent contained in the resin layer (A) contains the following compound (A-a) and at least one of (A-b) and (A-c): (A-a) (A-a1) A polymer obtained by doping a compound consisting of thiophene or a thiophene derivative with another anionic compound, and (A-a2) A polymer obtained by self-doping a compound consisting of thiophene or a thiophene derivative having an anionic group (A-b) A (meth)acrylic polymer having a styrene structure (A-c) (A-c1) A compound obtained by doping polyglycerin and (A-c2) An alkylene oxide adduct to polyglycerin, or a derivative thereof 12. The laminated film according to any one of claims 1 to 6, wherein the thickness of the resin layer (A) is 0.002 to 1.0 μm.

13. The laminated film according to any one of claims 1 to 6, wherein the thickness of the cured resin layer (B) is 0.5 to 10 μm.

14. The laminated film according to any one of claims 1 to 6, wherein the surface resistivity of the cured resin layer (B) of the laminated film is lower than the surface resistivity of a single layer of the cured resin layer (B).

15. A laminated film according to any one of claims 1 to 6, for surface protection.

16. A laminated film according to any one of claims 1 to 6, for use in displays.

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