JP6253423B2 - Antistatic optical laminate - Google Patents

Description

  The present invention relates to an optical laminate that is mainly provided on the display surface of a liquid crystal display (LCD), and more particularly to an optical laminate that eliminates (improves) charging of the outermost surface of the laminate.

  The surface of the display device such as a liquid crystal display is reflected on the surface in order to prevent the visibility of the image from being disturbed by indoor lighting such as fluorescent lamps, sunlight from windows, and the shadow of the operator. Functional films (optical laminates) such as anti-glare films with a fine concavo-convex structure (which has anti-glare properties) that can suppress external reflections and prevent external environment reflections Is provided on the outermost surface.

  These functional films have an antiglare layer in which a fine concavo-convex structure is formed on a translucent substrate such as polyethylene terephthalate (hereinafter referred to as “PET”) or triacetyl cellulose (hereinafter referred to as “TAC”). One layer provided and one obtained by laminating a low refractive index layer on a light diffusing layer are generally manufactured and sold, and development of a functional film that provides a desired function by a combination of layer configurations is in progress.

  In order to control the surface shape and appearance of the functional film, fluorine-based materials and silicone-based materials are added as additives. These additives also have a function of imparting antifouling properties to the coating film surface and a function of increasing the surface strength due to surface slipperiness, and in particular, the effect is enhanced by being unevenly distributed on the coating film surface.

  In the process of manufacturing a polarizing plate, when a functional film is bonded to the surface of a polyvinyl alcohol (PVA) film, it is bonded using an aqueous adhesive. In order to improve the adhesiveness with water-based adhesives, it has been the mainstream to saponify functional films in advance and bond them to PVA films. Recently, however, solvent-free systems such as UV adhesives have been used instead of water-based adhesives. Adhesives have come to be used, and this saponification treatment step can be omitted (for example, Patent Document 2).

Japanese Patent Laid-Open No. 09-258023 JP2012-247531A

  Although the direct cause is unknown, there has been a problem that the surface of the functional film, which is presumed to be due to the absence of the saponification treatment, is charged. When manufacturing a liquid crystal display device, a protective film is attached to protect the functional layer of the functional film that is the outermost surface, mainly during polarizing plate manufacturing and when assembling the liquid crystal panel, and the protective film is peeled off when checking the function of the assembly. The work of pasting and peeling off the protective film causes the surface of the functional film to be charged.

  In addition to liquid crystal display devices, functional films containing additives such as fluorine components and silicone components have problems of increasing the chargeability of the coating surface, and in the production process using the film, dust adhesion, film transportability It is related to the problem of deterioration. In order to solve this problem, methods such as reducing the amount of fluorine component or silicone component added or adding an antistatic agent to increase the conductivity of the coating surface are taken. However, it is difficult to achieve compatibility with appearance control, and it is difficult to control only the charging characteristics without reducing the addition amount of the fluorine component and the silicone component.

  Therefore, the present invention can control the charging characteristics of the outermost surface of the functional film without reducing the addition amount of the fluorine component and the silicone component, and further, the outermost surface of the functional film can be repeatedly bonded and peeled off. It is an object of the present invention to provide an antistatic optical laminate that is difficult to be charged.

  The antistatic optical laminate of the present invention (1) is a laminate in which at least one optical functional layer is laminated on one side of a translucent substrate, and the opposite side of the laminate to the translucent substrate. The outermost surface of the substrate is plasma-treated.

  The antistatic optical laminate of the present invention (2) is characterized by using a non-polymerizable gas as a process gas for plasma treatment.

  The antistatic optical laminate of the present invention (3) is characterized in that the non-polymerizable gas used for the process gas contains oxygen.

  The antistatic optical laminate of the present invention (4) is characterized in that the optical functional layer is made of a translucent resin containing a leveling agent.

  The antistatic optical laminate of the present invention (5) is characterized by having no antistatic layer.

  The polarizing plate of the present invention is characterized in that a polarizing element is provided on the translucent substrate side of the antistatic optical laminate.

  The display device of the present invention comprises an antistatic optical laminate or the above polarizing plate on the viewing side surface of a transmissive display.

  According to the present invention, by providing a plasma treatment on the outermost surface of the optical laminate opposite to the translucent substrate, it is possible to provide an antistatic optical laminate that is hardly charged even when used on the display device surface. it can. In particular, since it is difficult to be charged even if the protective film is repeatedly bonded and peeled at the time of manufacturing the display device, the inspection time of various devices can be shortened by eliminating the need for the charge removing operation.

  Each component of the antistatic optical laminate of the present invention will be described in detail.

<< Translucent substrate >>
The translucent substrate used in the present invention is not particularly limited as long as it is translucent, and glass such as quartz glass and soda glass can be used, but PET, TAC, polyethylene naphthalate (PEN), poly Methyl methacrylate (PMMA), polycarbonate (PC), polyimide (PI), polyethylene (PE), polypropylene (PP), polyvinyl alcohol (PVA), polyvinyl chloride (PVC), cycloolefin copolymer (COC), norbornene-containing resin, Various resin films such as polyethersulfone, cellophane, and aromatic polyamide can be suitably used. In addition, when using for PDP and LCD, PET and a TAC film are more preferable.

  The higher the transparency of these translucent substrates, the better. However, the total light transmittance (JIS K7105) is 80% or more, more preferably 90% or more. Further, the thickness of the translucent substrate is preferably thin from the viewpoint of weight reduction, but considering the productivity and handling property, the one in the range of 1 to 700 μm, preferably 6 to 250 μm is used. Is preferred.

  Also, by performing surface treatment such as alkali treatment, corona treatment, plasma treatment, sputtering treatment, surface treatment such as surfactant, silane coupling agent, or surface modification treatment such as Si deposition on the translucent substrate. Since the adhesion between the translucent substrate and the optical functional layer can be improved, the scratch resistance in the optical functional layer is improved.

<Translucent resin>
The optical functional layer according to the present invention can disperse translucent fine particles in a translucent resin. Here, the “translucent resin” is a total solid component excluding translucent fine particles in the paint (matrix component). The translucent resin is preferably formed by curing an energy curable resin that is cured by energy such as heat or radiation with energy, and is formed by curing the radiation curable resin composition with radiation. Although it is more preferable that it is, it is not specifically limited. Here, the radiation curable resin composition constituting the translucent resin includes radical polymerizable functional groups such as acryloyl group, methacryloyl group, acryloyloxy group, methacryloyloxy group, epoxy group, vinyl ether group, oxetane group. The composition which mixed the monomer, oligomer, prepolymer which has cationic polymerizable functional groups, such as these independently or suitably was used. Examples of monomers include methyl acrylate, methyl methacrylate, methoxy polyethylene methacrylate, cyclohexyl methacrylate, phenoxyethyl methacrylate, ethylene glycol dimethacrylate, dipentaerythritol hexaacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, and the like. it can. As oligomers and prepolymers, polyester acrylate, polyurethane acrylate, polyfunctional urethane acrylate, epoxy acrylate, polyether acrylate, acrylate compounds such as alkit acrylate, melamine acrylate, silicone acrylate, unsaturated polyester, tetramethylene glycol diglycidyl ether, Epoxy compounds such as propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, bisphenol A diglycidyl ether and various alicyclic epoxies, 3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[((3- Oxeta such as ethyl-3-oxetanyl) methoxy] methyl} benzene, di [1-ethyl (3-oxetanyl)] methyl ether Mention may be made of the compound. These can be used alone or in combination.

  The radiation curable resin composition can be cured by electron beam irradiation as it is, but in the case of curing by ultraviolet irradiation, it is necessary to add a photopolymerization initiator. The radiation used may be any of ultraviolet rays, visible rays, infrared rays, and electron beams. Further, these radiations may be polarized or non-polarized. Photopolymerization initiators include radical polymerization initiators such as acetophenone, benzophenone, thioxanthone, benzoin, and benzoin methyl ether, and cationic polymerization starts such as aromatic diazonium salts, aromatic sulfonium salts, aromatic iodonium salts, and metallocene compounds. The agents can be used alone or in appropriate combination.

  In addition to the radiation curable resin composition, a polymer resin can be added and used as long as the polymerization and curing are not hindered. This polymer resin is a thermoplastic resin that is soluble in an organic solvent used in the resin layer coating described later, and specifically includes acrylic resins, alkyd resins, polyester resins, cellulose, cellulose derivatives, and the like. This resin preferably has an acidic functional group such as a carboxyl group, a phosphoric acid group, or a sulfonic acid group.

  In addition, additives such as a leveling agent, a thickener, and an antistatic agent can be used. The leveling agent works to equalize the tension on the surface of the coating and repair defects such as craters and orange peel before forming the coating. Substances with lower interfacial tension and surface tension than the radiation curable resin composition are used. . Leveling agents include fluorine leveling agents having a perfluoroalkyl group in the molecular structure and silicone leveling agents having an organically modified polysiloxane, which are suitable for forming a good coating film. Therefore, the charge amount is increased by using a leveling agent as an additive. The thickener has a function of imparting thixotropy to the radiation curable resin composition, and is effective in forming fine uneven shapes on the surface of the resin layer by preventing sedimentation of translucent fine particles and pigments. The thickener is not particularly limited, but for example, it is preferable to use synthetic mica. Furthermore, it is preferable to organically treat the surface of the thickener with a quaternary ammonium salt or the like. By performing the treatment, the affinity with the resin and the metal oxide is increased, the performance is improved, and the suitability for workability is also improved.

  The translucent resin in the optical functional layer is mainly composed of a cured product of the above-mentioned radiation curable resin composition, but the formation method is to apply a paint comprising the radiation curable resin composition and an organic solvent. The organic solvent is volatilized and then cured by electron beam or ultraviolet irradiation. As the organic solvent used here, it is necessary to select a solvent suitable for dissolving the radiation curable resin composition. Specifically, in consideration of coating suitability such as wettability to a light-transmitting substrate, viscosity, and drying speed, an alcohol type, an ester type, a ketone type, an ether type, or an aromatic hydrocarbon is used alone or in combination. Solvents can be used.

<Translucent fine particles>
The translucent fine particles used in the optical functional layer according to the present invention include, for example, acrylic resin, polystyrene resin, styrene-acrylic copolymer, polyethylene resin, epoxy resin, silicone resin, polyvinylidene fluoride, and polyfluorinated ethylene-based resin. Organic translucent fine particles made of can be used.

  Here, the translucent fine particles contained in the optical functional layer preferably have a refractive index difference of 0.05 or less and 0.03 or less with respect to the radiation curable translucent resin layer. Is more preferable, and it is more preferable that it is 0.01 or less. When the difference in refractive index between the radiation curable translucent resin layer and the translucent fine particles is larger than 0.05, the degree of light scattering becomes too large and the contribution to high contrast is reduced. The refractive index of the translucent fine particles is preferably 1.45 to 1.58, more preferably 1.50 to 1.57. “Refractive index” refers to a measured value according to JIS K-7142.

  Next, the particle size of the translucent fine particles is preferably 0.3 to 10 μm, and more preferably 1 to 5 μm. When the particle size is smaller than 0.3 μm, the antiglare property is lowered. When the particle size is larger than 10 μm, it is not preferable because glare occurs and the surface unevenness becomes too large and the surface becomes whitish. Further, the particle diameter of the light-transmitting fine particles is preferably 20 to 80% of the film thickness, and more preferably 30 to 70%. “Particle size” refers to the average value of the diameters of 100 particles measured with an electron microscope. Of the total number, the fine powder and coarse powder mixed in the production process of the fine particles are less than 5% (more preferably less than 1%). Although the ratio of the translucent fine particles in the translucent resin is not particularly limited, it is preferably 1 to 50% by weight of the solid component in the optical functional layer, and more preferably 5 to 10% by weight. Is preferred. When it is within this range, it is preferable for satisfying characteristics such as an antiglare function and glare, and it is easy to control the fine uneven shape and light diffusion on the surface of the optical functional layer.

<Low reflection layer>
In order to improve the contrast, a low reflection layer can be provided as a second optical functional layer on the first optical functional layer. In this case, the refractive index of the low reflective layer needs to be lower than the refractive index of the optical functional layer, and is preferably 1.45 or less. Examples of materials having these characteristics include LiF (refractive index n = 1.4), MgF2 (n = 1.4), 3NaF · AlF3 (n = 1.4), AlF3 (n = 1.4), Inorganic low-reflective material containing inorganic material such as Na3AlF6 (n = 1.33), which is contained in acrylic resin or epoxy resin, fluorine-based, silicone-based organic compound, thermoplastic resin, thermosetting Organic low reflection materials such as mold resins and radiation curable resins. Among them, a fluorine-based fluorine-containing material is particularly preferable in terms of preventing contamination. The low reflective layer preferably has a critical surface tension of 20 dyne / cm or less. When the critical surface tension is larger than 20 dyne / cm, it becomes difficult to remove the dirt adhered to the low reflection layer.

  Examples of the fluorine-containing material include vinylidene fluoride copolymers, fluoroolefin / hydrocarbon copolymers, fluorine-containing epoxy resins, fluorine-containing epoxy acrylates, fluorine-containing silicones, which are easily dissolved in organic solvents. , Fluorine-containing alkoxysilanes, and the like. These can be used alone or in combination.

  Further, 2- (perfluorodecyl) ethyl methacrylate, 2- (perfluoro-7-methyloctyl) ethyl methacrylate, 3- (perfluoro-7-methyloctyl) -2-hydroxypropyl methacrylate, 2- (perfluoro- 9-methyldecyl) ethyl methacrylate, fluorine-containing methacrylate such as 3- (perfluoro-8-methyldecyl) -2-hydroxypropyl methacrylate, 3-perfluorooctyl-2-hydroxylpropyl acrylate, 2- (perfluorodecyl) ethyl acrylate , Fluorine-containing acrylates such as 2- (perfluoro-9-methyldecyl) ethyl acrylate, 3-perfluorodecyl-1,2-epoxypropane, 3- (perfluoro-9-methyldecyl) -1,2-epoxypropane It epoxide, radiation-curable fluorine-containing monomers such as epoxy acrylate, oligomers, and the like prepolymer. These can be used alone or in combination.

  Furthermore, it is also possible to use a low reflection material obtained by mixing a sol obtained by dispersing ultrafine silica particles of 5 to 30 nm in water or an organic solvent and a fluorine-based film forming agent. A sol in which 5 to 30 nm ultrafine silica particles are dispersed in water or an organic solvent is a method in which alkali metal ions in an alkali silicate salt are dealkalized by ion exchange or the like, or a method in which an alkali silicate salt is neutralized with a mineral acid A known silica sol obtained by condensing active silicic acid known in the art, a known silica sol obtained by condensing alkoxysilane with hydrolysis in an organic solvent in the presence of a basic catalyst, and the above-mentioned aqueous sol An organic solvent-based silica sol (organosilica sol) obtained by substituting water in the silica sol with an organic solvent by a distillation method or the like is used. These silica sols can be used in both aqueous and organic solvent systems. In producing the organic solvent-based silica sol, it is not necessary to completely replace water with the organic solvent. The silica sol contains a solid content of 0.5 to 50% by weight as SiO2. Various structures such as a spherical shape, a needle shape, and a plate shape can be used as the structure of the silica ultrafine particles in the silica sol.

  As the film forming agent, alkoxysilane, metal alkoxide, hydrolyzate of metal salt, or fluorine-modified polysiloxane can be used. Among the film forming agents as described above, it is particularly preferable to use a fluorine compound because the critical surface tension of the low reflection layer is lowered and adhesion of oil can be suppressed. The low reflection layer of the present invention is prepared by diluting the above-mentioned materials with a solvent, for example, spin coater, roll coater, printing, etc. on the radiation curable resin layer, drying, heat, radiation (in the case of ultraviolet rays) Can be obtained by curing using the above-mentioned photopolymerization initiator. Radiation curable fluorine-containing monomers, oligomers and prepolymers are excellent in stain resistance, but have poor wettability, so depending on the composition, there may be a problem of repelling the low reflection layer on the radiation curable resin layer, and low reflection. Since there is a possibility that the layer may be peeled off from the radiation curable resin layer, the acryloyl type, methacryloyl type, acryloyloxy group, methacryloyloxy group, etc. described as the above-mentioned radiation curable resin used for the radiation curable resin layer, etc. It is desirable to mix and use monomers, oligomers and prepolymers having a polymerizable unsaturated bond as appropriate.

  When a plastic film such as PET or TAC that is easily damaged by heat is used for the translucent substrate, it is preferable to select a radiation curable resin as the material of the low reflection layer.

The thickness for the low reflection layer to exhibit a good antireflection function can be calculated by a known calculation formula. In the case where incident light is perpendicularly incident on the low reflection layer, the condition for the low reflection layer not to reflect light and to transmit 100% should satisfy the following relational expression. In the formula, N ₀ represents the refractive index of the low reflective layer, N _s represents the refractive index of the radiation curable resin layer, h represents the thickness of the low reflective layer, and λ ₀ represents the wavelength of light.

  According to the above formula (1), in order to prevent reflection of light by 100%, a material in which the refractive index of the low reflective layer is the square root of the refractive index of the lower layer (radiation curable resin layer) should be selected. I know it ’s good. However, in reality, it is difficult to find a material that completely satisfies this mathematical formula, and a material that is as close as possible is selected. In the above equation (2), the optimum thickness as the antireflection film of the low reflection layer is calculated from the refractive index of the low reflection layer selected in the equation (1) and the wavelength of light. For example, if the refractive indexes of the radiation curable resin layer and the low reflection layer are 1.50 and 1.38, the wavelength of light is 550 nm (visibility standard), and these values are substituted into the above equation (2), The thickness of the low reflection layer is calculated to be optimal when the optical film thickness is around 0.1 μm, preferably in the range of 0.1 ± 0.01 μm.

<Structure of optical functional layer>
The film thickness of the optical functional layer is preferably in the range of 3 to 25 μm, more preferably in the range of 5 to 15 μm, and still more preferably in the range of 6 to 12 μm. When the film thickness is thinner than 3 μm, fine particles having different specific gravity cannot be sufficiently separated in the thickness direction. When it is thicker than 25 μm, curling occurs due to curing shrinkage of the optical functional layer, microcracks occur, adhesion to the translucent substrate decreases, and light transmission decreases. And it becomes a cause of the cost increase by the increase in the amount of required coating materials accompanying the increase in film thickness.

<Antistatic layer>
It is not essential to provide an antistatic layer as the optical functional layer according to the present invention. The antistatic layer is made by depositing a metal oxide film such as aluminum or tin, or a metal oxide film such as ITO very thinly by sputtering, metal fine particles such as aluminum or tin, whisker, antimony or the like on a metal oxide such as tin oxide. Polyesters such as fillers formed from doped fine particles, whiskers, 7,7,8,8-tetracyanoquinodimethane and electron donors (donors) such as metal ions and organic cations Dispersed in resin, acrylic resin, epoxy resin, etc., provided by solvent coating, etc., polypyrrole, polyaniline etc. doped with camphor sulfonic acid etc. can be provided by a method provided by solvent coating, etc. By applying plasma treatment to the outermost surface of the antistatic optical laminate, there is sufficient antistatic Because it can impart sex, it is possible to reduce the cost of providing a separate antistatic layer.

<Plasma discharge treatment>
As the plasma discharge treatment, either a low pressure plasma or an atmospheric pressure plasma discharge treatment method may be used. However, when a laminate is manufactured by a roll-to-roll coating method, the atmospheric pressure plasma discharge treatment method is more suitable for continuous production. It is preferable.

  Examples of the plasma gas used as a process gas for plasma discharge treatment include inert gases such as helium, argon, krypton, xenon, neon, radon, and nitrogen, oxygen, air, carbon monoxide, carbon dioxide, and tetrachloride. Carbon, chloroform, hydrogen, ammonia, carbon tetrafluoride, trifluoromethane, acetone, silane and the like can be arbitrarily selected. Further, a known fluorinated gas or a mixed gas of the above gases may be used. In the present invention, it is preferable that the inert gas contains a small amount of oxygen as the plasma gas species. Although the detailed reason is unknown, it is because the plasma discharge treatment under the same treatment density condition is less likely to occur than the charging of the antistatic optical laminate.

The treatment density in the plasma discharge treatment is preferably in the range of 0.1 to 100 W / cm ² , more preferably in the range of 0.5 to 30 W / cm ² .

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

<Example 1>
(Preparation of paint)
The paints listed in Table 1 below were prepared as the paints used for producing the optical laminate of the present invention. The addition amount in a table | surface shows a weight part. The paint was prepared by stirring the mixture for 1 hour with a homogenizer.

(Formation of optical functional layer)
The paint 1 was applied on one side of a 40 μm-thick triacetylcellulose translucent substrate (Fuji Film KK, Fujitac TD-40) so that the dry film thickness would be 6 μm by a bar coating method at 100 ° C. After drying for 1 minute, the coating film was cured by ultraviolet irradiation (lamp: high-pressure mercury lamp, lamp output: 120 W / cm, integrated light quantity: 120 mJ / cm) to form an optical functional layer on the translucent substrate.

(Plasma treatment)
On the optical functional layer, plasma treatment was performed at a power supply of 1900 W, an electrode gap: 2 mm, a process gas: nitrogen 99.5% + dry air 0.5%, a treatment temperature: 25 ° C., a treatment time: 20 seconds, The optical layered body of Example 1 was obtained.

<Example 2>
Fabrication was performed in the same manner as in Example 1 except that paint 2 was used instead of paint 1 in the formation of the optical functional layer, and an optical laminate of Example 2 was obtained.

<Example 3>
An optical laminate of Example 3 was obtained in the same manner as in Example 1 except that the process gas in the plasma treatment was changed to 100% nitrogen.

<Example 4>
The optical laminate of Example 4 was prepared in the same manner as in Example 1 except that paint 2 was used instead of paint 1 in the formation of the optical functional layer, and the process gas in the plasma treatment was changed to 100% nitrogen. Got.

<Comparative Example 1>
Fabrication was performed in the same manner as in Example 1 except that plasma treatment was not performed, and an optical laminate of Comparative Example 1 was obtained.

<Comparative example 2>
The optical laminated body of Comparative Example 2 was obtained in the same manner as in Comparative Example 1 except that paint 2 was used instead of paint 1 in the formation of the optical functional layer.

<Comparative Example 3>
The optical laminated body of Comparative Example 3 was obtained in the same manner as in Comparative Example 1 except that the paint 3 was used instead of the paint 1 in the formation of the optical functional layer.

<Comparative Example 4>
The optical laminated body of Comparative Example 4 was obtained in the same manner as in Comparative Example 1 except that paint 4 was used instead of paint 1 in the formation of the optical functional layer.

  The following measurement evaluation was performed about the optical laminated body of Examples 1-2 and Comparative Examples 1-4 which were obtained as mentioned above.

(Defect inspection)
In the defect inspection, the presence or absence of coating defects (crater, orange peel, etc.) was visually confirmed on the surface of each optical laminate sample opposite to the translucent substrate.

(Surface element analysis)
In the surface elemental analysis, the surface of each optical laminate sample on the side opposite to the light-transmitting substrate was converted into a perfluoroalkyl group as a charged component using an X-ray photoelectron spectrometer (manufactured by ULVAC-PHI, Inc .: Quantera SXM). Evaluation was made by quantitative measurement of the resulting fluorine atoms and silicon atoms derived from the organically modified polysiloxane.

(Peeling withstand voltage)
The peeling withstand voltage is obtained by laminating an antistatic protective film (manufactured by Fujimori Kogyo Co., Ltd .: AS3-310) on the surface of each optical laminate sample opposite to the translucent substrate and storing it for 24 hours. The antistatic protective film was peeled off at a peeling speed of 30 m / min in an environment of 23 ° C. and RH 55%, and the charged voltage immediately after the surface of the optical laminate sample was measured with a surface potentiometer (Cishid electrostatic company: Evaluation was made by measuring with Statilon M2).

  The results of measurement evaluation in Examples 1 to 4 and Comparative Examples 1 to 4 are as shown in Table 2.

  The antistatic optical laminates of Examples 1 to 4 of the present invention had a peeling band voltage of 0.5 kV or less, and could be used without problems in the production of polarizing plates and display devices. The optical laminates of Comparative Example 1 and Comparative Example 2 that were not subjected to plasma treatment had a peeling band voltage of 10.0 kV or more, which hindered the production of polarizing plates and display devices. From the relationship between Example 1 and Comparative Example 1 and Example 2 and Comparative Example 2, it can be seen that the surface atomic weight due to plasma treatment is reduced to about 1/5, and the amount of leveling agent added is reduced accordingly. In Example 3 and Comparative Example 4, not only coating defects occurred due to a decrease in the amount of leveling agent added, but the stripping voltage did not decrease as expected.

  By plasma-treating the outermost surface of the optical laminate, an antistatic optical laminate having a low withstand voltage can be obtained without providing an antistatic layer provided in a conventional optical laminate for a display device. Therefore, it can contribute to the production of a polarizing plate and a display device at a lower cost.

Claims (5)

A method for producing an antistatic optical laminate in which an antiglare layer is laminated on one side of a translucent substrate,
The antistatic optical laminate is a polarizing plate provided with a polarizing element on the translucent substrate side,
The antiglare layer is
Methyl acrylate, methyl methacrylate, methoxy polyethylene methacrylate, cyclohexyl methacrylate, phenoxyethyl methacrylate, ethylene glycol dimethacrylate, dipentaerythritol hexaacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate,
Polyester acrylate, polyurethane acrylate, multifunctional urethane acrylate, epoxy acrylate, polyether acrylate, alkit acrylate, melamine acrylate, silicone acrylate,
Unsaturated polyester, tetramethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, bisphenol A diglycidyl ether,
3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, or di [1-ethyl (3-oxetanyl)] methyl ether alone, Or a mixture of several cured
Plasma-treating the antiglare layer which is the outermost surface of the laminate opposite to the light-transmitting substrate ;
The plasma treatment uses a non-polymerizable gas containing no metal as a plasma gas species,
The method for producing an antistatic optical laminate, wherein the non-polymerizable gas contains oxygen. The method for producing an antistatic optical laminate according to claim 1, wherein the antiglare layer is made of a translucent resin containing a leveling agent. The method for producing an antistatic optical laminate according to claim 1 or 2, wherein the antistatic optical laminate does not have an antistatic layer. To produce antistatic optical layered body by the method for producing antistatic optical laminate according to any one of claims 1 to 3, the polarizing element on the transparent substrate side of the antistatic optical laminate A method for producing a polarizing plate , comprising: providing a polarizing plate. To produce antistatic optical layered body by the method for producing antistatic optical laminate according to any one of claims 1 to 3,
Or by the method of manufacturing antistatic optical laminate according to any one of claims 1 to 3 to produce an antistatic optical laminate, a polarizing element on the transparent substrate side of the antistatic optical laminate To produce a polarizing plate ,
A method for producing a display device , comprising the antistatic optical laminate or the polarizing plate on a viewing-side surface of a transmissive display .