JP5925012B2 - High refractive index anti-blocking layer forming composition - Google Patents

Description

  The present invention relates to a high refractive index antiblocking layer forming composition, an antiblocking film obtained by coating the high refractive index antiblocking layer forming composition, and a transparent conductive layer on at least one surface of the antiblocking film. The present invention relates to a transparent conductive laminate in which is formed.

  When a hard coating is applied to a thermoplastic film such as a PET film, it may be stored in a manufacturing process, such as being wound into a roll. When another layered body is layered on a base material layer such as a PET film on which a hard coat has been formed, the adhesive force or chemical force acts between the layers, and it becomes an attached state, and when using each layered body In addition, a force for peeling off each layered body may be required, it may be difficult to peel off due to the strong adhesive force, or the layered body may be destroyed if it is forced to peel off. Such a phenomenon is called blocking.

  In such a case, a back coat layer is formed by applying a paint kneaded with a particulate matter of about 1 μm on the opposite surface of the base material that is not hard-coated, and the surface is uneven. By providing and reducing the contact area between each layer, adhesion between layered bodies may be prevented. For example, Japanese Patent Application Laid-Open No. 2004-151937 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2005-132897 (Patent Document 2) disclose a technique in which a backcoat layer containing a particulate matter is formed.

  The technique for preventing adhesion between layered bodies by using the above-mentioned granular material is effective, but since the unevenness of the particles must appear on the surface, the thickness of the coating film is smaller than the particle size (for example, 0 .About.5 μm), the mechanical strength of the backcoat layer is lowered, the substrate layer such as a PET film is easily scratched, and glare occurs. In the case of a thermoplastic resin layer that requires transparency, such a defect is a fatal defect because optical characteristics and transparency are lowered.

  In the method of mixing transparent resin fine particles in the back coat layer on the opposite side of the hard coat layer, there is also a technique for forming irregularities on the surface by mixing resin particles not only in the back coat layer but also in the hard coat layer itself. (Japanese Patent Laid-Open No. 2004-042653 (Patent Document 3)) The blended particles have an average particle size in the range of 0.5 to 20 μm. When the particles are mixed, it is necessary to reduce the film thickness in order to form unevenness on the surface, the film strength becomes weak, the film is easily damaged, and the coating film properties are deteriorated. In addition, since the particle size of the particles is relatively large, even if transparent particles are used as in Patent Document 3, the optical characteristics may be impaired.

  In addition, the transparent conductive laminated body used for a touch panel etc. is mentioned as one of the field | areas where the said PET film and also PC film are used. Both of these PET films and PC films are characterized by high refractive index while having high transparency and suitable physical properties. Due to the high refractive index of the film, a difference in refractive index from the resin layer occurs. Due to this difference in refractive index, interference fringes are generated, resulting in a problem that visibility is lowered. Here, as one of means for preventing the generation of interference fringes, there is a means for increasing the refractive index of various resin layers formed in the production of the transparent conductive laminate.

JP 2004-151937 A JP 2005-132897 A JP 2004-042653 A

  An object of the present invention is to provide a technique capable of effectively preventing defects such as adhesion between layered materials such as a resin film, that is, a blocking phenomenon, without adversely affecting visibility.

The present invention
A high refractive index anti-blocking layer-forming composition comprising a first component and a second component,
The first component is an unsaturated double bond-containing acrylic copolymer,
The second component is
(A) a phenol novolac acrylate having 2 or more acrylate groups, and (B) an aromatic group-containing mono- or poly- (1 or 2 alkylene oxide structure having 2 or 3 carbon atoms in one molecule) (Meth) acrylate,
The phenol novolac acrylate (A) is included in an amount of 60 to 85 parts by mass and the (meth) acrylate (B) in an amount of 15 to 30 parts by mass with respect to 100 parts by mass of the second component.
The difference ΔSP between the SP value (SP1) of the first component and the SP value (SP2) of the second component is in the range of 1 to 4,
The mass ratio of the first component and the second component contained in the composition is: first component: second component = 0.5: 99.5 to 20:80,
After coating the high refractive index antiblocking layer forming composition, the first component and the second component cause layer separation, and an antiblocking layer having fine irregularities on the surface is formed.
A high-refractive index anti-blocking layer forming composition is provided, which solves the above problems.

  The phenol novolac acrylate (A) has the following formula (I)

（Ｉ）

(I)

[In Formula (I), R ¹ is H or CH ₂ OH, R ² is H or OH, n is 2 to 5, and m is 0 to 5. ]
It is preferable that it is a compound shown by these.

  The (meth) acrylate (B) is preferably an aromatic group-containing (meth) acrylate having a refractive index in the range of 1.56 to 1.64.

In the high refractive index anti-blocking layer forming composition, the total content of ZnO, TiO ₂ , CeO ₂ , SnO ₂ , ZrO ₂ and indium-tin oxide is 0.0001% by mass or less in the composition. preferable.

The present invention also provides
A transparent polymer substrate, and
An anti-blocking layer formed by coating the substrate with the high refractive index anti-blocking layer forming composition,
An anti-blocking film having
The anti-blocking layer has a refractive index of 1.565 to 1.620, and
The anti-blocking layer has an arithmetic average roughness (Ra) of 0.001 to 0.09 μm and a ten-point average roughness (Rz) of 0.01 to 0.5 μm.
An anti-blocking film is also provided.

  The anti-blocking layer preferably has a thickness of 0.05 to 10 μm.

As a preferred embodiment of the anti-blocking film,
The substrate is a PET film having a thickness of 20 to 300 μm,
Examples of the anti-blocking film include those characterized in that no cracks are generated in the anti-blocking layer when the film is stretched 15% in the MD direction at 20 ° C. under a pulling speed of 5 m / min.

As another preferred embodiment of the anti-blocking film,
The substrate is a polycarbonate film having a thickness of 30 to 200 μm,
Examples of the anti-blocking film include those characterized in that cracks do not occur in either the anti-blocking layer or the substrate when bent 180 ° under the conditions of 25 ° C. and 60 degrees / second.

  The anti-blocking film preferably has a total light transmittance of 88% or more and a haze value of 2% or less.

  The present invention further provides a transparent conductive laminate in which a transparent conductive layer is formed on at least one surface of the anti-blocking film.

  It is preferable that the transparent conductive layer is a crystalline layer containing indium oxide and the thickness of the transparent conductive layer is 5 to 50 nm.

  It is preferable that a metal oxide layer exists between the anti-blocking layer and the transparent conductive layer, and the thickness of the metal oxide layer is 0.5 to 5.0 nm.

  The present invention also provides a touch panel having the transparent conductive laminate.

  The anti-blocking layer-forming composition of the present invention can provide an anti-blocking layer that is a resin layer having irregularities on the surface, simply by photocuring after coating on a substrate and drying as necessary. . The obtained anti-blocking film has high hardness and is hardly damaged. In addition, since no particulate matter having an average particle diameter of more than 0.5 μm is used, there is an advantage that visibility and optical characteristics are not impaired. The anti-blocking film obtained by coating the anti-blocking layer forming composition of the present invention exhibits an effect that a blocking phenomenon (for example, interlayer adhesion) does not occur even when a plurality of the anti-blocking films are overlapped. Moreover, even if the obtained anti-blocking film is preserve | saved as a winding roll, there exists an advantage that a blocking phenomenon (for example, difficulty of peeling from a winding roll) does not occur.

  In the present invention, in addition to the effect of suppressing the blocking phenomenon, the obtained anti-blocking layer has a high refractive index and also has excellent extensibility. Due to this feature, the occurrence of interference fringes can be suppressed, and there is an advantage that extremely high visibility is achieved.

High refractive index antiblocking layer forming composition The high refractive index antiblocking layer forming composition of the present invention comprises a first component and a second component. The first component is an unsaturated double bond-containing acrylic copolymer. The second component, (A) having two or more acrylate groups, having 1-2 phenol novolak acrylate, and (B) alkylene oxide structure having 2 or 3 carbon atoms in the molecule, an aromatic Group-containing mono- or poly (meth) acrylates. The phenol novolac acrylate (A) is contained in an amount of 60 to 85 parts by mass and the (meth) acrylate (B) is contained in an amount of 15 to 30 parts by mass with respect to 100 parts by mass of the second component. Further, the difference ΔSP between the SP value (SP1) of the first component and the SP value (SP2) of the second component is in the range of 1 to 4, and the first component and the second component contained in the composition The mass ratio is on condition that the first component: the second component = 0.5: 99.5 to 20:80. This high refractive index anti-blocking layer forming composition is characterized in that after coating, the first component and the second component cause layer separation, and an anti-blocking layer having fine irregularities on the surface is formed.

First component As the first component, an unsaturated double bond-containing acrylic copolymer is used. An unsaturated double bond-containing acrylic copolymer is, for example, a resin obtained by copolymerizing a (meth) acrylic monomer and another monomer having an ethylenically unsaturated double bond, a (meth) acrylic monomer and another ethylenically unsaturated Acrylic acid or glycidyl acrylate for resins reacted with monomers having double bonds and epoxy groups, resins made by reacting (meth) acrylic monomers with other monomers having ethylenically unsaturated double bonds and isocyanate groups, etc. And those having an unsaturated double bond and other functional groups added thereto. One of these unsaturated double bond-containing acrylic copolymers may be used alone, or two or more thereof may be mixed and used. The unsaturated double bond-containing acrylic copolymer preferably has a weight average molecular weight of 2,000 to 100,000, more preferably 5,000 to 50,000.

Second component The second component is:
(A) a phenol novolac acrylate having 2 or more acrylate groups, and (B) an aromatic group-containing mono- or poly- (1 or 2 alkylene oxide structure having 2 or 3 carbon atoms in one molecule) (Meth) acrylate,
including. Hereinafter, each component (A) and (B) is explained in full detail.

(A) Phenol novolac acrylate having 2 or more acrylate groups The high refractive index antiblocking layer-forming composition of the present invention comprises (A) a phenol having 2 or more acrylate groups as a second component. Contains novolac acrylate. When the high-refractive index anti-blocking layer forming composition contains the phenol novolac acrylate (A) as the second component, the resulting anti-blocking layer is transparent and has a high hardness and a high hardness layer. Become. Thereby, generation | occurrence | production of an interference fringe can be prevented effectively.

  The phenol novolac acrylate (A) has the following formula (I)

（Ｉ）

(I)

[In Formula (I), R ¹ is H or CH ₂ OH, R ² is H or OH, n is 2 to 5, and m is 0 to 5. ]
It is preferable that it is a phenol novolak-type acrylate shown by these. In said formula (I), it is more preferable that n is 2-4 and m is 0-3, n is 2-4, and it is still more preferable that m is 0-1.

  The weight average molecular weight of the phenol novolac acrylate (A) is preferably 400 to 2500, and more preferably 450 to 2000. The hydroxyl value of the phenol novolac acrylate (A) is preferably 100 to 180 mgKOH / g, and more preferably 120 to 160 mgKOH / g.

  In this specification, the weight average molecular weight of each component can be measured by a gel permeation chromatography method. In the measurement of the weight average molecular weight, a high-speed GPC apparatus such as HLC-8220 GPC (manufactured by Tosoh Corporation) can be used. As a specific measurement condition of the weight average molecular weight using HLC-8220GPC (manufactured by Tosoh Corporation), 2 g of a test sample was weighed, treated in a vacuum dryer at 40 ° C. for 2 hours to remove moisture, and then a THF solution. And a measurement is performed under the conditions of a column injection amount: 10 μl and a flow rate: 0.35 ml / min.

  The said phenol novolak-type acrylate (A) is on condition that 60-85 mass parts is contained with respect to 100 mass parts of 2nd components. When the amount of the phenol novolac acrylate (A) is less than 60 parts by mass and when the amount of the phenol novolac acrylate (A) exceeds 85 parts by mass, the hardness of the obtained anti-blocking layer is low. There is a bug.

(B) Aromatic group-containing mono- or poly (meth) acrylate compound having 1 to 2 alkylene oxide structures having 2 or 3 carbon atoms in one molecule . as a two-component, including (B) having 1-2 per molecule of alkylene oxide structure having 2 or 3 carbon atoms, an aromatic group-containing mono- or poly (meth) acrylate. This (meth) acrylate (B) preferably has a viscosity of less than 300 mPa · s and a refractive index in the range of 1.56 to 1.64.

In (meth) acrylate component (B), by the alkylene oxide structure having 2 or 3 carbon atoms are contained 1-2 in a molecule, to design the viscosity of component (B) less than 300 mPa · s It becomes possible. Further, in (meth) acrylate component (B), so that the alkylene oxide structure having 2 or 3 carbon atoms by inclusion 1-2 in one molecule, elongation of the hard coat layer obtained are improved . Here, examples of the “alkylene structure having 2 or 3 carbon atoms” include an ethylene oxide structure and a propylene oxide structure.

  The (meth) acrylate of component (B) is further characterized by having an aromatic group. When the (meth) acrylate of the component (B) has an aromatic group, a high refractive index such as a refractive index in the range of 1.56 to 1.64 is achieved.

As the aromatic group-containing (meth) acrylate can be preferably used as the component (B) in the present invention, e.g., having one or two alkylene oxide structure having 2 or 3 carbon atoms in the molecule, alkyleneoxy phenol ( Examples include (meth) acrylate, alkyleneoxylated orthophenylphenol (meth) acrylate, alkyleneoxylated metaphenylphenol (meth) acrylate, alkyleneoxylated paraphenylphenol (meth) acrylate, and alkyleneoxylated cumylphenol (meth) acrylate. It is done. Among these, (meth) acrylate having two aromatic groups is more preferable in that it has a high refractive index.

  The refractive index of the component (B) can be measured with an Abbe refractometer by a method based on JIS K0062.

  The viscosity of component (B) is preferably less than 300 mPa · s. When the viscosity of a component (B) exceeds 300 mPa * s, there exists a problem that the curing reactivity of a composition will be inferior and the hardness of the hard-coat layer obtained will become low. The viscosity of the component (B) is more preferably in the range of 1 to 300 mPa · s, still more preferably in the range of 1 to 200 mPa · s.

  The viscosity of the component (B) can be measured with a B-type viscometer (TVB-22L manufactured by Toki Sangyo Co., Ltd.). Examples of the B-type viscometer include TVB-22L (manufactured by Toki Sangyo Co., Ltd.).

  The component (B) preferably has a weight average molecular weight in the range of 150 to 600, and more preferably in the range of 200 to 400.

  In this invention, it is on condition that a component (B) is contained 15-30 mass parts with respect to 100 mass parts of 2nd components contained in a high refractive index antiblocking layer forming composition. When the (meth) acrylate (B) is contained in the high-refractive index anti-blocking layer forming composition in the above mass range, the obtained anti-blocking layer has an advantage of high hardness and high refractive index. When the amount of the component (B) is less than 15 parts by mass and when the amount of the component (B) exceeds 30 parts by mass, there is a problem that the hardness of the obtained anti-blocking layer is lowered.

Other (meth) acrylates The second component in the high refractive index anti-blocking layer forming composition of the present invention may contain other (meth) acrylates in addition to the components (A) and (B). Examples of such (meth) acrylates include polyfunctional (meth) acrylate monomers and / or oligomer compounds. These polyfunctional (meth) acrylate monomers and / or oligomer compounds undergo a curing reaction based on the reaction of (meth) acryloyl groups upon irradiation with active energy rays after coating the composition for forming a high refractive index antiblocking layer. There is an advantage that an anti-blocking layer having high hardness can be obtained.

  The polyfunctional (meth) acrylate monomer and / or oligomer compound preferably has two or more (meth) acryloyl groups. By having two or more (meth) acryloyl groups, there is an advantage that an anti-blocking layer having high hardness can be obtained after irradiation with active energy rays.

  Specific examples of the polyfunctional (meth) acrylate monomer and / or oligomer compound include, for example, hydroxypropylated trimethylolpropane triacrylate, isocyanuric acid ethylene oxide-modified diacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, and trimethylolpropane triacrylate. Examples thereof include acrylate, tris (acryloxyethyl) isocyanurate, ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, and oligomers thereof. These monomers or oligomers may be used alone or in combination of two or more.

  When the second component contained in the high-refractive index anti-blocking layer forming composition contains other (meth) acrylates, 100 parts by mass of the second component contained in the high-refractive index anti-blocking layer forming composition The range of 1 to 30 parts by mass is preferable, and the range of 1 to 25 parts by mass is more preferable.

High refractive index antiblocking layer forming composition The high refractive index antiblocking layer forming composition is composed of a first component and a second component, and addition of a solvent, a photopolymerization initiator, a catalyst, a photosensitizer and the like as required. It is prepared by mixing the agent. The ratio of the first component to the second component in the high refractive index anti-blocking layer forming composition of the present invention is: first component: second component = 0.5: 99.5 to 20:80. As for this ratio, 1st component: 2nd component = 1: 99-20: 80 is more preferable, and it is further more preferable that it is 1: 99-15: 85.

  In the high refractive index anti-blocking layer forming composition, phase separation is caused by the difference in SP value between the first component and the second component. By this phase separation, an anti-blocking layer having fine irregularities on the surface is formed. In the present invention, the difference (ΔSP) between the SP value of the first component and the SP value of the second component is within the range of 1 to 4. When the difference between the SP value of the first component and the SP value of the second component is 1 or more, the compatibility of the resins with each other is low, whereby the first component and the second component are applied after application of the anti-blocking layer forming composition. It is thought that phase separation is brought about. The ΔSP is more preferably in the range of 2.0 to 3.5.

  The SP value is an abbreviation for solubility parameter (solubility parameter) and is a measure of solubility. The SP value indicates that the polarity is higher as the numerical value is larger, and the polarity is lower as the numerical value is smaller.

  For example, the SP value can be measured by the following method [references: SUH, CLARKE, J. et al. P. S. A-1, 5, 1671-1681 (1967)].

Measurement temperature: 20 ° C
Sample: Weigh 0.5 g of resin in a 100 ml beaker, add 10 ml of good solvent using a whole pipette, and dissolve with a magnetic stirrer.
solvent:
Good solvent: Dioxane, acetone, etc. Poor solvent: n-hexane, ion-exchanged water, etc. Muddy point measurement: The poor solvent is added dropwise using a 50 ml burette, and the point at which turbidity occurs is defined as the amount added.

  The SP value δ of the resin is given by the following equation.

Vi: Molecular volume of the solvent (ml / mol)
φi: Volume fraction of each solvent at cloud point δi: SP value of solvent ml: Low SP poor solvent mixed system mh: High SP poor solvent mixed system

  The high refractive index anti-blocking layer forming composition of the present invention may further contain components such as various solvents, photopolymerization initiators and additives in addition to the first component and the second component.

  Preferred organic solvents when the first component and the second component are the above combinations include, for example, ketone solvents such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone; alcohol solvents such as methanol, ethanol, propanol, isopropanol, and butanol An ether solvent such as anisole, phenetol propylene glycol monomethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether; One of these solvents may be used alone, or two or more organic solvents may be mixed and used. When using a solvent, for example, 1-9900 parts by mass, preferably 10-900 parts by mass is added to 100 parts by mass of the total amount of the first component and the second component (collectively referred to as “resin component”) Can do.

  The high refractive index antiblocking layer forming composition preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include 2-hydroxy-2methyl-1phenyl-propan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1- [4- (methylthio) phenyl] -2. -Morpholinopropan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, etc. Can be mentioned. A preferable amount of the photopolymerization initiator is 0.01 to 20 parts by mass, and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the resin component.

  The high refractive index antiblocking layer-forming composition may contain conventional additives such as an antistatic agent, a plasticizer, a surfactant, an antioxidant, and an ultraviolet absorber, if necessary. When using these additives, it is preferable that it is 0.01-20 mass parts with respect to 100 mass parts of resin components, and it is more preferable that it is 1-10 mass parts.

  The high refractive index anti-blocking layer forming composition can form a resin layer having irregularities without using resin particles or the like by using the first component and the second component as described above. There is. Therefore, it is preferable that the anti-blocking layer forming composition does not contain resin particles. However, the anti-blocking layer forming composition may contain at least one or more inorganic particles, organic particles, or a composite thereof, if necessary. These particles are not particularly added for the purpose of forming irregularities on the surface, but are added to form more uniform and fine irregularities by controlling phase separation and precipitation. These particles have an average particle size of 0.5 μm or less, preferably 0.01 to 0.3 μm. When it exceeds 0.5 μm, the transparency slightly decreases.

  Examples of inorganic particles include silica, alumina, titania, zeolite, mica, synthetic mica, calcium oxide, zirconium oxide, zinc oxide, magnesium fluoride, smectite, synthetic smectite, vermiculite, ITO (indium oxide / tin oxide), ATO There may be mentioned at least one selected from the group consisting of (antimony oxide / tin oxide), tin oxide, indium oxide and antimony oxide.

  Examples of the organic particles include at least one selected from the group consisting of acrylic, olefin, polyether, polyester, urethane, polyester, silicone, polysilane, polyimide, and fluorine particles.

  The anti-blocking layer having fine irregularities on the surface can be formed by coating and then curing the high refractive index anti-blocking layer forming composition. Examples of the coating method of the anti-blocking layer forming composition include dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, and extrusion coating. Examples of the thickness of the anti-blocking layer include an embodiment having a thickness of 0.01 to 20 μm.

After coating the high refractive index antiblocking layer-forming composition, it can be phase separated and cured by irradiating light. As light to irradiate, for example, light having an exposure amount of 0.1 to 3.5 J / cm ² , preferably 0.5 to 1.5 J / cm ² can be used. Further, the wavelength of the irradiation light is not particularly limited, and for example, irradiation light having a wavelength of 360 nm or less can be used. Such light can be obtained using a high-pressure mercury lamp, an ultra-high pressure mercury lamp, or the like. By irradiating light in this way, phase separation and curing will occur.

Anti-blocking film This invention further provides the anti-blocking film formed using the said high refractive index anti-blocking layer forming composition. This anti-blocking film has a transparent polymer base material and an anti-blocking layer formed by coating the high refractive index anti-blocking layer forming composition on the base material. The antiblocking layer in the present invention is characterized by having a high refractive index of 1.565 to 1.620 in addition to having excellent antiblocking performance.

  In the anti-blocking film of the present invention, a PET film or a polycarbonate film is preferably used as the transparent polymer substrate. This is because the PET film and the polycarbonate film are suitably used as a base film for a film having a transparent conductive layer constituting a touch panel from the viewpoints of high film strength and transparency and low cost. On the other hand, these films generally have a high refractive index of 1.5 or more. Since the refractive index of these films is higher than the refractive index of the resin component constituting the commonly used anti-blocking film, the difference in refractive index with the anti-blocking layer increases, and the frequency of occurrence of interference fringes increases. There's a problem.

  Here, the interference fringes refer to iris-like reflection generated by interference of light reflected at each interface in a multilayer body composed of a transparent film and a transparent coat layer. This interference fringe tends to appear prominently under irradiation of a three-wavelength fluorescent lamp. The three-wavelength light-emitting fluorescent lamp is a fluorescent lamp characterized by a strong emission intensity at a specific wavelength, which is characterized by the fact that things can be clearly seen.

  The high refractive index antiblocking layer-forming composition of the present invention is characterized in that an antiblocking layer having a high refractive index can be formed. Therefore, even if an antiblocking layer is formed on a transparent substrate film such as a PET film or a polycarbonate film, there is a feature that no interference fringes are generated.

  In addition, you may apply | coat the high refractive index antiblocking layer forming composition of this invention to base film other than the said PET film or a polycarbonate film. Examples of such a base film include triacetyl cellulose (TAC) film, diacetylene cellulose film, acetate butyrate cellulose film, polyether sulfone film, polyacrylic resin film, polyurethane resin film, polyester film, and polysulfone. Examples thereof include a film, a polyether film, a polymethylpentene film, a polyether ketone film, and a (meth) acrylonitrile film.

  The thickness of the transparent polymer substrate can be appropriately selected according to the use, but is generally about 20 to 300 μm.

  The anti-blocking layer formed by the high refractive index anti-blocking layer forming composition of the present invention is characterized by having fine irregularities. The arithmetic average roughness (Ra) of the surface roughness curve of the anti-blocking layer is preferably less than 0.1 μm, more preferably 0.001 to 0.09 μm, and 0.002 to 0.00. Particularly preferred is 08 μm. Here, the arithmetic mean roughness (Ra) of the roughness curve is a parameter defined in JIS B 0601-2001. When the arithmetic average roughness (Ra) of the surface roughness curve of the anti-blocking layer is 0.1 μm or more, problems such as generation of glare and whitening of the coating film may occur. If the value of Ra is less than the particularly preferable range, a blocking phenomenon occurs, which is not preferable. JIS B 0601-2001 is a Japanese industrial standard and is a standard based on ISO 4288.

  Arithmetic average roughness (Ra) of the roughness curve is a sample of only the reference length in the direction of the average line from the roughness curve, the X axis in the direction of the average line of this extracted portion, and Y in the direction of the vertical magnification. When the axis is taken and the roughness curve is expressed by y = f (x), the value obtained by the following formula is expressed in micrometers (μm).

  The anti-blocking layer formed by the high refractive index anti-blocking layer forming composition of the present invention preferably has an Rz of 0.5 μm or less. Here, Rz is the ten-point average roughness of the roughness curve, and is a parameter specified in JIS B0601-2001. Rz is more preferably 0.3 μm or less, and further preferably 0.2 μm or less. The lower limit is preferably 0.01 μm.

  The arithmetic average roughness (Ra) and ten-point average roughness (Rz) of the surface roughness curve of the anti-blocking layer formed by the high refractive index anti-blocking layer forming composition of the present invention are, for example, manufactured by Kosaka Laboratory Ltd. Can be measured according to JIS B 0601-2001 using a high-precision fine shape measuring instrument or a color 3D laser microscope manufactured by Keyence Corporation.

  Since the anti-blocking layer formed by the composition for forming a high refractive index anti-blocking layer of the present invention has an irregular, fine and dense uneven shape, it exhibits excellent anti-blocking properties. The anti-blocking layer in the present invention is also advantageous in that the sharpness of an image displayed by a light source such as a liquid crystal module is not deteriorated. In particular, in recent high-definition liquid crystal display devices, the pitch of light rays emitted from the liquid crystal has become finer. Therefore, in order to maintain image clarity, a finer and denser uneven shape is required. The anti-blocking layer in the present invention has an advantage that it has a fine and dense concavo-convex shape and is not accompanied by a decrease in image sharpness such as a decrease in contrast and a decrease in luminance.

  The anti-blocking layer in the present invention is characterized in that a high refractive index of 1.565 to 1.620 of the anti-blocking layer is achieved without using a high refractive index agent. The refractive index of the anti-blocking layer can be measured according to JIS K7142 using, for example, an Abbe refractometer.

The anti-blocking film of the present invention preferably has a total light transmittance of 85% or more, and more preferably 90% or more. Further, the anti-blocking film of the present invention preferably has a haze of 2% or less, more preferably 1% or less.
In the present _{invention, ZnO,} since the _{TiO 2, CeO 2, SnO 2} , be free of high refractive index such as ZrO ₂ high refractive index has been achieved, need to include such a high refractive index agent There is no. Therefore, it is possible to achieve a high total light transmittance and a low haze value as described above. More specifically, in the high refractive index anti-blocking layer forming composition, the total content of ZnO, TiO ₂ , CeO ₂ , SnO ₂ , ZrO ₂ and indium-tin oxide is 0.0001% by mass or less in the composition. Is preferred. This is because when a high refractive index agent such as a metal oxide is present in the anti-blocking layer, the extensibility and the bending resistance are generally inferior as compared with the resin-only layer.

The total light transmittance (T _t (%)) is calculated by the following equation by measuring the incident light intensity (T ₀ ) with respect to the anti-blocking film and the total transmitted light intensity (T ₁ ) transmitted through the anti-blocking film. .

Ｈ：ヘイズ（曇価）（％）
Ｔ_ｄ：拡散透光率（％）
Ｔ_ｔ：全光線透過率（％） The haze is calculated from the following formula in accordance with JIS K7105.

H: Haze (cloudiness value) (%)
T _d : Diffuse transmittance (%)
T _t : Total light transmittance (%)

  The total light transmittance and the haze value can be measured using, for example, a haze meter (manufactured by Suga Test Instruments Co., Ltd.).

  The anti-blocking layer formed by using the high refractive index anti-blocking layer forming composition of the present invention is characterized by having high extensibility in addition to having high hardness and refractive index. Therefore, the anti-blocking film in this invention can be used suitably in preparation of the film which has a transparent conductive layer which comprises a touchscreen etc., for example.

  In mobile phones such as smartphones equipped with touch panels, tablet PCs, and portable information terminal devices, there is a strong demand for smaller, thinner, and lighter devices. Therefore, thinning of the base film is also required for members constituting the touch panel electrode. On the other hand, by reducing the thickness of the base film, when the base film is provided with an anti-blocking layer, the occurrence frequency of defects that cause warping or curling of the film increases, and workability and productivity decrease. There is a problem. These defects are considered to depend on the difference in physical properties (for example, thermal shrinkage rate, thermal expansion rate, etc.) between the anti-blocking layer and the base film. Since the antiblocking film in this invention has high extensibility, there exists a tendency for curl to become small with respect to various base materials.

  In the anti-blocking film of the present invention, a transparent conductive layer and an optical interference layer that controls the reflectance by optical interference can be used in combination in an appropriate order as necessary according to the application. The order in which the transparent conductive layer, the optical interference layer, and the high-refractive index anti-blocking layer are stacked is not particularly limited as long as it fulfills a function expected to appear depending on the application. For example, when the order of lamination is used as a substrate for a touch panel, the transparent conductive layer is A, the optical interference layer is B, the high refractive index antiblocking layer to be the subject of the present invention is C, the transparent polymer base material is D, and the present invention. For example, A / B / C / D / E, A / B / C / D / C, A / B / B / C / D / E, A / B / B / C / D / C, A / C / D / E / B, A / C / D / C / B, A / C / D / E / B / B, A / C / D / C / B / B or the like.

  The optical interference layer described above refers to a layer that prevents or suppresses reflected light by appropriately combining a high refractive index layer and a low refractive index layer. The optical interference layer is composed of at least one high refractive index layer and at least one low refractive index layer. Two or more combination units of the high refractive index layer and the low refractive index layer may be used. When the optical interference layer is composed of one high refractive index layer and one low refractive index layer, the thickness of the optical interference layer is preferably 30 nm to 150 nm, and more preferably 50 nm to 150 nm. The optical interference layer can be formed by either a wet method or a dry method. For example, in the wet method, doctor knife, bar coater, gravure roll coater, curtain coater, knife coater, spin coater, etc., spray method, dipping method, etc., in dry method, PVD method such as sputtering method, vacuum deposition method, ion plating method, etc. A printing method, a CVD method, or the like can be applied.

  A transparent conductive laminate constituting a touch panel or the like is generally a film having a transparent conductive layer. The transparent conductive layer is not particularly limited, but is a crystalline layer containing indium oxide, more specifically, mainly composed of indium such as ITO (indium-tin oxide) and IZO (indium-zinc oxide). A crystalline layer is preferably used. As a method for forming the transparent conductive layer, there are a PVD method such as a sputtering method, a vacuum deposition method, and an ion plating method, a coating method, a printing method, and a CVD method, and the PVD method or the CVD method is preferable.

  By carrying out these processing steps for providing the transparent conductive layer, a partial load is applied to the base film having the anti-blocking layer. Therefore, the transparent conductive layer of the transparent conductive laminate, the anti-blocking layer and the base film The film may be twisted based on the difference in thermal shrinkage and thermal expansion between the two. The anti-blocking layer provided using the high refractive index anti-blocking layer forming composition of the present invention is characterized by having high visibility and good hardness and high extensibility. The resulting antiblocking layer has high extensibility, so that the antiblocking layer follows well even when the base film is locally thermally expanded by heating in the stage of providing the transparent conductive layer, etc. As a result, there is an advantage that defects such as film warp do not occur.

  More specifically, regarding the extensibility of the anti-blocking layer, in the case of the anti-blocking film in which the transparent polymer substrate on which the high-refractive index anti-blocking layer forming composition is coated is a PET film having a thickness of 20 to 300 μm When the anti-blocking film is stretched 15% in the MD direction at 20 ° C. under the condition of a pulling speed of 5 mm / sec, there is a state in which no cracks are generated in the anti-blocking layer. Here, the case where it is 0.05-10 micrometers as a film thickness of an anti blocking layer is mentioned, for example.

  In general, the production of a polymer base film is performed by winding a resin base material in a molten state in a roll shape while being perpendicular to the vertical direction (winding direction: MD direction) and the horizontal direction (TD direction: MD direction). The film is produced by a biaxial stretching method in which a film having a uniform thickness is produced. In this manufacturing method, high stress remains in the MD direction. Therefore, the obtained film tends to cause thermal expansion / shrinkage particularly in the MD direction. Generation of cracks (film cracks) and the like can be effectively verified by performing a test in which the obtained anti-blocking film is stretched in the MD direction, which is the direction wound during the production of the polymer base film. There is an advantage.

  Moreover, when the transparent polymer base material which comprises an antiblocking film is a polycarbonate film, the expansion | extension performance of the formed antiblocking layer can be evaluated by verifying the bending resistance of an antiblocking film. . Polycarbonate is a material with excellent physical properties such as heat resistance and impact resistance, but especially in the case of a polycarbonate film with a thin film thickness, cracks may occur due to stress such as bending. . When a polycarbonate film having a thin film thickness is used as a base film in this way, when the extensibility of the anti-blocking layer formed on the base film is high, by providing an anti-blocking layer, It becomes possible to prevent the occurrence of cracks. The antiblocking layer formed by the high refractive index antiblocking layer forming composition of the present invention has high extensibility. Therefore, there is an advantage that the toughness against bending stress can be improved in an anti-blocking film using a polycarbonate having a thin film thickness as a base film. More specifically, in the case where the transparent polymer substrate on which the high refractive index antiblocking layer forming composition is coated is an antiblocking film which is a polycarbonate film having a thickness of 30 to 200 μm, Even when it is bent 180 ° under the conditions of 60 ° C. and 60 ° C., there is a state in which no cracks are generated in either the antiblocking layer or the substrate. Here, the case where it is 0.05-10 micrometers as a film thickness of an anti-blocking layer is mentioned, for example.

  The anti-blocking layer formed using the high refractive index anti-blocking layer forming composition of the present invention is characterized by having good anti-blocking performance and hardness, and high visibility and extensibility. The anti-blocking layer formed by the high refractive index anti-blocking layer forming composition of the present invention has a high refractive index. Therefore, even when the anti-blocking layer in the present invention is provided on a substrate film having a high refractive index such as a PET film or a polycarbonate film, there is an advantage that no interference fringes are generated. The antiblocking layer in this invention can be used suitably especially in the film which has a transparent conductive layer which comprises a touchscreen electrode.

  The following examples further illustrate the present invention, but the present invention is not limited thereto. In the examples, “parts” and “%” are based on mass unless otherwise specified.

Production Example 1 Production of Unsaturated Double Bond-Containing Acrylic Copolymer (I) A mixture consisting of 187.2 g of isobornyl methacrylate, 2.8 g of methyl methacrylate, and 10.0 g of methacrylic acid was mixed. This mixture was added to 360 g of propylene glycol monomethyl ether heated to 110 ° C. under a nitrogen atmosphere in a 1000 ml reaction vessel equipped with a stirring blade, a nitrogen introducing tube, a cooling tube and a dropping funnel. At the same time as an 80.0 g solution of propylene glycol monomethyl ether containing 2.0 g of ate, the solution was added dropwise at a constant rate over 3 hours, and then reacted at 110 ° C. for 1 hour.

  Thereafter, a 17 g solution of propylene glycol monomethyl ether containing 0.2 g of tertiary butyl peroxy-2-ethyl hexaate was added dropwise and reacted at 110 ° C. for 30 minutes.

  6 g of propylene glycol monomethyl ether solution containing 1.5 g of tetrabutylammonium bromide and 0.1 g of hydroquinone was added to the reaction solution, and further, 24.4 g of 4-hydroxybutyl acrylate glycidyl ether and propylene glycol monomethyl ether 5 were added while air bubbling. 0.0 g of the solution was added dropwise over 1 hour, followed by further reaction over 5 hours.

  An unsaturated double bond-containing acrylic copolymer having a number average molecular weight of 5500 and a weight average molecular weight (Mw) of 18000 was obtained. This resin had SP value: 9.7 and Tg: 92 ° C.

Production Example 2 Production of Phenol Novolac Type Acrylate (1) In a reactor equipped with a stirrer, thermometer, dropping funnel and reflux device, 150 g of phenol novolac resin (weight average molecular weight 700-900, epoxy equivalent 150-200) and epichlorohydrin 550g was mixed and 110g of 48.5% sodium hydroxide aqueous solution was dripped over 2 hours under pressure reduction conditions of 100 degreeC and 100-200 mmHg . After completion of the reaction, the temperature is cooled to room temperature, an excess aqueous sodium hydroxide solution is neutralized with an acid, heated under reduced pressure to remove excess epichlorohydrin, the product is dissolved in methyl isobutyl ketone, washed with water and filtered. By-product salts were removed to obtain a phenol novolac type epoxy resin solution.
Metoquinone 1000 ppm and triphenylphosphine 2000 ppm are added to 100 parts by weight of the solid content of the obtained phenol novolac type epoxy resin, and acrylic acid is added dropwise at 100 ° C. until the acid value becomes 1 mgKOH / g or less. A phenol novolac type epoxy acrylate (1) was obtained.
The obtained phenol novolak epoxy acrylate (1) had a weight average molecular weight of 950, a hydroxyl value of 140 mgKOH / g, and a refractive index of 1.572. The SP value was 12.7.

Production Example 3 Production of Phenol Novolac Type Acrylate (2) In a reactor equipped with a stirrer, a thermometer, a dropping funnel and a reflux device, 150 g of phenol novolac resin (weight average molecular weight 900-1100, epoxy equivalent 150-200) and epichlorohydrin 550g was mixed and 110g of 48.5% sodium hydroxide aqueous solution was dripped over 2 hours under pressure reduction conditions of 100 degreeC and 100-200 mmHg . After completion of the reaction, the temperature is cooled to room temperature, an excess aqueous sodium hydroxide solution is neutralized with an acid, heated under reduced pressure to remove excess epichlorohydrin, the product is dissolved in methyl isobutyl ketone, washed with water and filtered. By-product salts were removed to obtain a phenol novolac type epoxy resin solution.
Metoquinone 1000 ppm and triphenylphosphine 2000 ppm are added to 100 parts by weight of the solid content of the obtained phenol novolac type epoxy resin, and acrylic acid is added dropwise at 100 ° C. until the acid value becomes 1 mgKOH / g or less. A phenol novolac epoxy acrylate (2) was obtained.
The obtained phenol novolak type epoxy acrylate (2) had a weight average molecular weight of 1200, a hydroxyl value of 137 mgKOH / g, and a refractive index of 1.571. The SP value was 12.6.

Example 1
As the first component, the unsaturated double bond-containing acrylic copolymer (I) obtained in Production Example 1 was used. As the component (A) of the second component, the phenol novolac type epoxy acrylate (1) obtained in Production Example 2 is used, and as the component (B), an ethoxylated orthophenylphenol acrylate (having one ethoxy structure per molecule ) . An anti-blocking layer-forming composition was prepared using an acrylate, a viscosity of 130 mPa · s at 25 ° C., a refractive index of 1.577, and an SP value of 10.6. The raw materials shown in Table 1 were sequentially mixed at the solid content mass shown in Table 1 and stirred to obtain an anti-blocking layer forming composition.

In addition, the viscosity measurement of the ethoxylated orthophenylphenol acrylate of the component (B) was obtained by collecting 100 ml of the ethoxylated orthophenylphenol acrylate of the component (B) as a test sample in a glass container and adjusting the temperature to 20 ° C. Using a viscometer (TVB-22L manufactured by Toki Sangyo Co., Ltd.) and M1Rotor, the measurement was performed at a rotation speed of 60 rpm.
The refractive index of component (B) was measured using an Abbe refractometer by a method based on JIS K0062.

  In addition, SP value of the 2nd component was computed by the weight average with respect to SP value and content of each component, such as a component (A) contained in a 2nd component, a component (B), and another component.

The obtained antiblocking layer-forming composition was dropped onto a Teijin DuPont 188 μm optical PET film (KEFW) and coated using a bar coater # 12.
After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ ultraviolet rays with an ultraviolet irradiator (manufactured by Fusion) to obtain an antiblocking film having a PET film and an antiblocking layer having a thickness of 6.5 μm.

The obtained anti-blocking layer-forming composition was dropped onto a Teijin Chemicals 100 μm optical PC film (Pure Ace) and coated using a bar coater # 9.
After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ of ultraviolet rays using an ultraviolet irradiator (manufactured by Fusion) to obtain an antiblocking film having a polycarbonate film and an antiblocking layer having a thickness of 5.0 μm.

Examples 2-5
The type and amount of component (A) were changed to those described in Table 1, and pentaerythritol triacrylate (SP value: 12.7) was used as another (meth) acrylate contained in the second component. Except for the above, an anti-blocking layer forming composition was prepared in the same manner as in Example 1. Two types of anti-blocking films were obtained in the same manner as in Example 1 using the obtained anti-blocking layer forming composition.

Comparative Examples 1-5, 9
With the formulation shown in Table 2, an anti-blocking layer forming composition was prepared in the same manner as in the examples. Two types of anti-blocking films were obtained in the same manner as in Example 1 using the obtained anti-blocking layer forming composition.

Comparative Examples 6 and 10
With the formulation shown in Table 2, an anti-blocking layer forming composition was prepared in the same manner as in the examples.
The obtained antiblocking layer-forming composition was dropped onto a Teijin DuPont 188 μm optical PET film (KEFW) and coated using a bar coater # 13. After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ ultraviolet rays with an ultraviolet irradiator (manufactured by Fusion) to obtain an antiblocking film having a PET film and an antiblocking layer having a thickness of 6.5 μm.
Further, the obtained anti-blocking layer forming composition was dropped onto a 100 μm optical PC film (Pure Ace) manufactured by Teijin Chemicals and coated using a bar coater # 10. After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ of ultraviolet rays using an ultraviolet irradiator (manufactured by Fusion) to obtain an antiblocking film having a polycarbonate film and an antiblocking layer having a thickness of 5.0 μm.

Comparative Examples 7 and 11
With the formulation shown in Table 2, an anti-blocking layer forming composition was prepared in the same manner as in the examples.
The obtained antiblocking layer-forming composition was dropped onto a Teijin DuPont 188 μm optical PET film (KEFW) and coated using a bar coater # 16. After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ ultraviolet rays with an ultraviolet irradiator (manufactured by Fusion) to obtain an antiblocking film having a PET film and an antiblocking layer having a thickness of 6.5 μm.
Further, the obtained anti-blocking layer forming composition was dropped on a Teijin Chemicals 100 μm optical PC film (Pure Ace) and coated using a bar coater # 12. After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ of ultraviolet rays using an ultraviolet irradiator (manufactured by Fusion) to obtain an antiblocking film having a polycarbonate film and an antiblocking layer having a thickness of 5.0 μm.

Comparative Examples 8, 12, 13
With the formulation shown in Table 2, an anti-blocking layer forming composition was prepared in the same manner as in the examples.
The obtained antiblocking layer-forming composition was dropped onto a Teijin DuPont 188 μm optical PET film (KEFW) and coated using a bar coater # 20. After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ ultraviolet rays with an ultraviolet irradiation machine (manufactured by Fusion). In the case of using the anti-blocking layer forming composition of Comparative Example 12, an anti-blocking film having a PET film and an anti-blocking layer having a film thickness of 6.5 μm was obtained. On the other hand, when the anti-blocking layer forming composition of Comparative Examples 8 and 13 was used, the coating composition was not cured and an anti-blocking layer could not be provided.
Further, the obtained anti-blocking layer forming composition was dropped onto a Teijin Chemicals 100 μm optical PC film (Pure Ace) and coated using a bar coater # 14. After coating, the film was dried at 70 ° C. for 1 minute, and irradiated with 350 mJ ultraviolet rays with an ultraviolet irradiation machine (manufactured by Fusion). In the case of using the anti-blocking layer forming composition of Comparative Example 12, an anti-blocking film having a polycarbonate film and an anti-blocking layer having a thickness of 5.0 μm was obtained. On the other hand, when the anti-blocking layer forming composition of Comparative Examples 8 and 13 was used, the coating composition was not cured and an anti-blocking layer could not be provided.

Example 6
Sputtering method using the anti-blocking film obtained in Example 1 and further using an indium oxide-tin oxide target having a composition of indium oxide and tin oxide in a weight ratio of 95: 5 and a packing density of 98% on the cured resin layer Thus, an ITO layer was formed, and a transparent conductive laminate to be a movable electrode substrate was produced. The thickness of the formed ITO layer was about 30 nm, and the surface resistance value after film formation was about 150Ω / □. The interference fringes of the obtained transparent conductive laminate were not visually recognized.

  The following evaluation was performed about the antiblocking film obtained in the said Examples 1-5 and Comparative Examples 1-13. The evaluation results are shown in Tables 1 and 2.

Measurement of refractive index The refractive index was measured by the following method using an Abbe refractometer (2T measurement range nD = 1.3 to 1.7 manufactured by Atago Co., Ltd.).
On the main prism, a drop of an intermediate solution (monobromonaphthalene, etc.) was dropped with a dropper and a sample to be measured was placed. One drop of the intermediate solution was dropped on the sample with a dropper, and the secondary prism was closed. Here, the condition is that air does not enter the intermediate liquid layer.
Lamp light was incident on the sub-prism, the measurement knob was turned while looking through the eyepiece, the boundary of the light and darkness of the refractive field was adjusted to the intersection, the value of the scale field was read to 4 digits after the decimal point, and the refractive index was measured.

Evaluation of Hardness The hardness was measured using a pencil scratch coating film hardness tester (model P, pressure load 100 g to 1 kg, manufactured by Toyo Seiki Seisakusho).
A pencil for pencil scratch test (manufactured by the Japan Paint Inspection Association) manufactured by Mitsubishi Uni was used, and the tip of the lead was adjusted with abrasive paper (3MP-1000) so that it had a smooth and circular cross section. After placing the sample on the measuring table, the pencil was fixed so that the scratch angle was 45 °, and the test was performed under the condition of a load of 750 g. For each test, the test was repeated five times while shifting the test location while smoothing the core.
The presence or absence of dents on the surface of the coating film was confirmed visually based on the following evaluation criteria.
For example, in the case of a test using a 2H pencil,
When no dent was generated, it was determined as 2H.
When the occurrence of dents is 1 to 2, the pencil hardness is evaluated by one step down, and when there is no dent after one step, the hardness is evaluated as an intermediate region (H to 2H, etc.). did.
When the number of dents was 3 or more, it was judged as H or less, and the evaluation was performed in the same manner with one step lowered.

In addition, the hardness of the PET film used in preparation of the anti-blocking film of an Example and a comparative example is HB-F, and the hardness of a polycarbonate (PC) film is 5B-4B.
Therefore, in an anti-blocking film having a PET film and an anti-blocking layer, if the hardness is H or higher, the hardness is increased by two or more stages, and it is determined that the anti-blocking layer has sufficient hardness. .
In addition, in the anti-blocking film having the polycarbonate film and the anti-blocking layer, if the hardness is 3B or more, the hardness is increased by two or more steps, and it is determined that the anti-blocking layer has sufficient hardness. .

The elongation was measured using an autograph (AG-1S manufactured by Shimadzu Corporation).
A test sample is cut out to 10 mm × 150 mm, and is sandwiched between upper and lower chucks of the measuring instrument in a direction in which the longitudinal direction of the sample is extended. When a sample sample was stretched at a speed of 2 cm / sec under room temperature (20 ° C.) conditions, an elongation rate at which no breakage / crack occurred was obtained.

Bending resistance test method The sample was adjusted to 50 mm x 50 mm, and the sample was evaluated by bending it 180 °. Based on the following evaluation criteria, it performed visually.
○: Cracks do not occur in the coating film / base material.
Δ: Cracks can be confirmed only in the coating film.
X: The occurrence of cracks can be confirmed in both the coating film and the substrate.

Evaluation of anti-blocking (AB) performance The anti-blocking films obtained in Examples and Comparative Examples were cut into a size of 2 × 5 cm, and the coated surface was superposed on the surface of the PET film (no adhesive layer applied), and a glass plate And left at room temperature for 24 hours under the condition of 200 gf / cm ² . Thereafter, the blocking phenomenon (AB property) was visually evaluated according to the following criteria.
○: With anti-blocking property ×: Without anti-blocking property

Interference fringe evaluation method
Interference fringes (appearance evaluation)
The test piece was bonded to a 100 × 100 mm black acrylic plate using an optical film adhesive so that the coated surface was on the surface. A sample is placed at a distance of 10 cm vertically from the fluorescent tube of a stand-type three-wavelength fluorescent lamp (SLH-399, manufactured by TWINBARD) and visually observed. Visual observation was performed and judged based on the following evaluation criteria.
A: Interference fringes (interference patterns) are not visually recognized under a three-wavelength fluorescent lamp or in sunlight.
○: Interference fringes (interference patterns) are not visually recognized under a three-wavelength fluorescent lamp, but slightly visible under sunlight Δ: Interference fringes (interference patterns) are slightly visible ×: Interference fringes (interference patterns) Clearly visible

Interference fringes (transmission spectrum amplitude)
The light transmittance of the test piece was measured with an ultraviolet-visible spectrophotometer (UV-2450, manufactured by Shimadzu Corporation)
The determination was made based on the following evaluation criteria for the amplitude of the transmittance in the range of 500 to 750 nm.
○: The difference between the maximum value and the minimum value of the transmittance is less than 0.5% △: The difference between the maximum value and the minimum value of the transmittance is 0.5% or more and less than 1.0% ×: The maximum value and the minimum value of the transmittance Difference in value is 1.0% or more

In Table 1 and Table 2 above,
I-184: 1-hydroxycyclohexyl phenyl ketone, photopolymerization initiator bisphenol A EO-modified diacrylate: manufactured by Toagosei Co., Ltd., Aronix M-211B, bisphenol A EO (2 mol) -modified diacrylate, SP value 11.3
Acryloylmorpholine: SP value 11.9
Bifunctional urethane acrylate: NV100: CN-9893 (manufactured by Sartomer), SP value 11.1
High refractive index filler 1: Zirconia ZRMIBK30WT% (zirconium oxide, manufactured by CIK Nanotech)
High refractive index filler 2: Titania TiMIBK15WT% (titanium oxide, manufactured by CIK Nanotech)
Indicates.

The anti-booking film having an anti-blocking layer formed using the anti-blocking layer forming composition of the example has a good anti-blocking performance, no generation of interference fringes, and a high refractive index, It had good hardness. Furthermore, the obtained anti-booking film had high extensibility and bending resistance.
Comparative Examples 1 and 2 are examples in which the amount of component (B) is outside the scope of the present invention. In these cases, there was a problem that the hardness of the obtained film was lowered.
Comparative Example 3 is an example in which diacrylate having a bisphenol A skeleton was used instead of component (A). In Comparative Example 3, the refractive index of the obtained film was lowered, and the occurrence of interference fringes was confirmed. There was also a problem that the hardness was lowered.
Comparative Example 4 is an example using acryloylmorpholine instead of component (B). Also in Comparative Example 4, the refractive index of the obtained film was lowered, and the occurrence of interference fringes was confirmed. Moreover, the extensibility was also inferior.
Comparative Examples 5 to 8 are examples using zirconia oxide or titanium oxide, which is a high refractive index agent, instead of using the components (A) and (B). In these comparative examples, while the hardness was good, the antiblocking property and the extensibility were greatly inferior. Note that the composition of Comparative Example 8 did not cure.
Comparative Examples 9 to 13 are examples using bifunctional urethane acrylate for the purpose of imparting extensibility to the anti-blocking layer. In these comparative examples, the anti-blocking property was inferior, and although the extensibility was somewhat improved, the balance between the hardness and the refractive index was poor. Note that the composition of Comparative Example 13 did not cure.

  The anti-blocking layer forming composition of Comparative Examples 5 to 13 contains a high refractive index filler. By including the high refractive index filler, the refractive index itself of the obtained anti-blocking layer is certainly high. On the other hand, interference fringes are confirmed in any of the anti-blocking layers obtained in these comparative examples. The reason why the interference fringes were confirmed in these comparative examples is that the resin component forming the anti-blocking layer has a low refractive index, while the resin component has a high refractive index filler mixed therein. This is probably because of this. For this reason, even if the refractive index itself of the anti-blocking layer is increased, the resin component having a low refractive index has an adverse effect, and it is considered that an excellent interference fringe generation suppressing effect cannot be obtained.

  The anti-blocking layer formed by the anti-blocking layer-forming composition of the present invention is characterized by having excellent anti-blocking performance and good hardness, high visibility and extensibility. The anti-blocking layer formed by the anti-blocking layer forming composition of the present invention is further characterized by having a high refractive index. Therefore, even when the anti-blocking layer in the present invention is provided on a base film having a high refractive index such as a PET film or a polycarbonate film, there is an advantage that no interference fringes are generated.

Claims (13)

A high refractive index anti-blocking layer-forming composition comprising a first component and a second component,
The first component is an unsaturated double bond-containing acrylic copolymer,
The second component is
(A) a phenol novolac acrylate having 2 or more acrylate groups, and (B) an aromatic group-containing mono- or poly- (1 or 2 alkylene oxide structure having 2 or 3 carbon atoms in one molecule) (Meth) acrylate,
The phenol novolac acrylate (A) is included in an amount of 60 to 85 parts by mass and the (meth) acrylate (B) in an amount of 15 to 30 parts by mass with respect to 100 parts by mass of the second component.
The difference ΔSP between the SP value (SP1) of the first component and the SP value (SP2) of the second component is in the range of 1 to 4,
The mass ratio of the first component and the second component contained in the composition is: first component: second component = 0.5: 99.5 to 20:80,
After coating the high refractive index antiblocking layer forming composition, the first component and the second component cause layer separation, and an antiblocking layer having fine irregularities on the surface is formed.
High refractive index anti-blocking layer forming composition. The phenol novolac acrylate (A) has the following formula (I)

(I)
[In Formula (I), R ¹ is H or CH ₂ OH, R ² is H or OH, n is 2 to 5, and m is 0 to 5. ]
The high refractive index antiblocking layer forming composition of Claim 1 shown by these.   The high refractive index antiblocking according to claim 1 or 2, wherein the (meth) acrylate (B) is an aromatic group-containing (meth) acrylate having a refractive index in the range of 1.56 to 1.64. Layer forming composition. The high refractive index according to claim 1, wherein the total content of ZnO, TiO ₂ , CeO ₂ , SnO ₂ , ZrO ₂ and indium-tin oxide is 0.0001% by mass or less in the composition. Anti-blocking layer forming composition. A transparent polymer substrate, and
The anti-blocking layer formed by coating the base material with the high refractive index anti-blocking layer forming composition according to claim 1,
An anti-blocking film having
The anti-blocking layer has a refractive index of 1.565 to 1.620, and
The anti-blocking layer has an arithmetic average roughness (Ra) of 0.001 to 0.09 μm and a ten-point average roughness (Rz) of 0.01 to 0.5 μm.
Anti-blocking film.   The antiblocking film according to claim 5, wherein the antiblocking layer has a thickness of 0.05 to 10 μm. The substrate is a PET film having a thickness of 20 to 300 μm,
The anti-blocking film is characterized in that cracks do not occur in the anti-blocking layer when the film is stretched 15% in the MD direction at 20 ° C. under a pulling speed of 5 m / min.
The anti-blocking film according to claim 5 or 6. The substrate is a polycarbonate film having a thickness of 30 to 200 μm,
The anti-blocking film is characterized in that cracks do not occur in any of the anti-blocking layer and the base material when bent at 180 ° under the conditions of 25 ° C. and 60 degrees / second,
The anti-blocking film according to claim 5 or 6.   The antiblocking film according to any one of claims 5 to 8, wherein the antiblocking film has a total light transmittance of 88% or more and a haze value of 2% or less.   The transparent conductive laminated body in which the transparent conductive layer was formed on the at least one surface of the antiblocking film in any one of Claims 5-9.   The transparent conductive laminate according to claim 10, wherein the transparent conductive layer is a crystalline layer containing indium oxide, and the thickness of the transparent conductive layer is 5 to 50 nm.   The transparent conductive laminate according to claim 10 or 11, wherein a metal oxide layer is present between the anti-blocking layer and the transparent conductive layer, and the thickness of the metal oxide layer is 0.5 to 5.0 nm.   A touch panel having the transparent conductive laminate according to claim 10.