JP2017219597A - Production method of optical laminate, method for controlling contact angle of optical laminate with water, and optical laminate with protective film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of an optical laminate and an optical laminate with a protective film, by which hydrophilicity of a surface of a light-transmitting functional layer can be enhanced, and a method for controlling a contact angle of an optical laminate with water, by which a contact angle of a surface of a light-transmitting functional layer with water can be controlled.SOLUTION: In accordance with one embodiment of the present invention, a production method of an optical laminate 10 is provided, which includes the steps of: forming a light-transmitting functional layer 12 on at least one surface side of a light-transmitting substrate 11; removably sticking a protective film 13 having a base film 15 and an adhesive layer 16 disposed on one surface of the base film 15 to a surface 12A of the light-transmitting functional layer 12, with the adhesive layer 16; and removing the protective film 13 from the light-transmitting functional layer 12 so as to obtain the light-transmitting functional layer 12 in which the contact angle of the surface 12A of the light-transmitting functional layer 12 with water after removing the protective film 13 is smaller than a contact angle with water of the surface 12A of the light-transmitting functional layer 12 before sticking the protective film 13.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an optical laminate manufacturing method, an optical laminate water contact angle control method, and an optical laminate with a protective film.

  Conventionally, an image display device with a touch panel in which a touch panel is arranged on a display panel such as a liquid crystal display is known. In such a display device with a touch panel, information can be directly input by touching the image display surface with a finger or the like.

  As a method of fixing the touch panel on the display panel, an air gap method in which the touch panel and the display panel are fixed through an air layer, and a direct bonding method in which the touch panel and the display panel are fixed through a light-transmitting adhesive layer ( For example, see Patent Document 1.

  In the air gap method, due to the difference in refractive index between the touch panel and the air layer and the difference in refractive index between the air layer and the display panel, light may be reflected at each interface and visibility may be reduced. For this reason, the number of image display devices with a direct bonding type touch panel is increasing.

JP 2014-130290 A

  In an image display device with a direct bonding type touch panel, when forming a light-transmitting adhesive layer, a hydrophilic liquid curable adhesive layer composition is applied to the surface of the hard coat layer in the polarizing plate of the display panel. Since it is often applied, in order to improve wettability, it has been studied to reduce the contact angle with water on the surface of the hard coat layer.

  Here, in order to reduce the contact angle with respect to water on the surface of the hard coat layer, it may be possible to add a component for decreasing the contact angle with respect to water to the composition for hard coat layer. Even if it exists, it is not easy to reduce the contact angle with respect to the water in the surface of a hard-coat layer.

  The present invention has been made to solve the above problems. That is, the method for producing an optical laminate capable of easily reducing the contact angle with respect to water on the surface of the light-transmitting functional layer, the optical laminate with a protective film, and the contact angle with respect to water on the surface of the light-transmitting functional layer. It is an object of the present invention to provide a water contact angle control method for an optical laminate that can be controlled.

  According to one aspect of the present invention, a step of forming a light transmissive functional layer on at least one side of the light transmissive substrate, a substrate film on the surface of the light transmissive functional layer, and the substrate A step of attaching a protective film comprising an adhesive layer provided on one surface of the film so as to be peelable by the adhesive layer, and peeling the protective film from the light-transmitting functional layer, after peeling the protective film Obtaining a light-transmitting functional layer in which the contact angle with respect to water on the surface of the light-transmitting functional layer is lower than the contact angle with respect to water on the surface of the light-transmitting functional layer before application of the protective film. A method for producing an optical laminate is provided.

  According to another aspect of the present invention, the contact angle with respect to water of an optical laminate comprising a light transmissive substrate and a light transmissive functional layer provided on at least one side of the light transmissive substrate is controlled. A method for controlling a water contact angle of an optical layered body, wherein a base film is provided on one surface of the base film on the surface of a light-transmitting functional layer formed on at least one side of the base substrate A step of affixing a protective film with the adhesive layer so as to be peelable by the adhesive layer, and peeling off the protective film from the light-transmitting functional layer, and the light-transmitting functional layer after peeling of the protective film A method for controlling the water contact angle of an optical laminate, comprising lowering the contact angle of water on the surface of water with respect to the water on the surface of the light-transmitting functional layer before application of the protective film.

  According to another aspect of the present invention, an optical laminate with a protective film comprising an optical laminate and a protective film releasably attached to the optical laminate, wherein the optical laminate is a light transmissive member. And a light-transmitting functional layer provided on at least one side of the light-transmitting substrate, the protective film is provided on one surface of the substrate film and the substrate film, And an adhesive layer attached to the surface of the light transmissive functional layer, and water on the surface of the light transmissive functional layer after peeling of the protective film when the protective film is peeled from the optical laminate. An optical laminate with a protective film is provided in which the contact angle with respect to water is lower than the contact angle with water on the surface of the light-transmitting functional layer before the protective film is attached.

  According to the method for producing an optical laminate of one embodiment of the present invention and the optical laminate with a protective film of another embodiment, when the protective film is peeled from the optical laminate, the light-transmitting function after peeling of the protective film Since the contact angle of water on the surface of the layer is lower than the contact angle of water on the surface of the light transmissive functional layer before application of the protective film, the contact angle of water on the surface of the light transmissive functional layer is easily reduced. Can be made.

  According to the water contact angle control method for an optical layered body of another aspect of the present invention, the protective film is peeled off from the light-transmitting functional layer, and the contact angle of the surface of the light-transmitting functional layer with respect to water is determined by the protective film. Since the contact angle with water on the surface of the light-transmitting functional layer before pasting is lowered, the contact angle with respect to water on the surface of the light-transmitting functional layer can be easily controlled.

It is a figure which shows typically the manufacturing process of the optical laminated body which concerns on embodiment. It is a figure which shows typically the manufacturing process of the optical laminated body which concerns on embodiment. 1 is a schematic configuration diagram of an image display device with a touch panel according to an embodiment.

  Hereinafter, the manufacturing method of the optical laminated body which concerns on embodiment of this invention, the water contact angle control method of an optical laminated body, and the optical laminated body with a protective film are demonstrated, referring drawings. In the present specification, terms such as “laminate”, “sheet”, “film” and the like are not distinguished from each other based only on the difference in designation. Therefore, for example, “laminated body” is used to include a member that is also called a film or a sheet. In addition, “light transmittance” in the present specification means a property of transmitting light. For example, the total light transmittance is 50% or more, preferably 70% or more, more preferably 80% or more, particularly preferably. Including 90% or more. FIG. 1 and FIG. 2 are schematic configuration diagrams showing the manufacturing process of the optical laminate according to this embodiment.

<<< Manufacturing method of optical laminated body, water contact angle control method and optical laminated body with protective film >>>
First, as shown in FIG. 1A, a light transmissive functional layer 12 is formed on at least one side of a light transmissive substrate 11. In the present specification, the “light-transmitting functional layer” is a layer having a light-transmitting property and intended to exhibit some function in the optical laminate. Specifically, examples of the light-transmitting functional layer include a layer for exhibiting a function such as hard coat property or antireflection property. The light transmissive functional layer may be not only a single layer but also a laminate of two or more layers. In the present embodiment, the case where the light transmissive functional layer 12 is a layer having a hard coat property, that is, a hard coat layer will be described.

<< light transmissive substrate >>
The light-transmitting substrate 11 is not particularly limited as long as it has light-transmitting properties. For example, a cellulose acylate substrate, a cycloolefin polymer substrate, a polycarbonate substrate, an acrylic substrate, a polyester substrate, or a glass group is used. Materials.

  Examples of the cellulose acylate base material include a triacetyl cellulose base material and a diacetyl cellulose base material. A triacetylcellulose base material is a base material which can make an average light transmittance 50% or more in a visible light region of 380 to 780 nm. The average light transmittance of the triacetyl cellulose base material is preferably 70% or more, and more preferably 85% or more.

  In addition, as a triacetyl cellulose base material, in addition to pure triacetyl cellulose, cellulose acetate propionate, cellulose acetate butyrate and the like may be used in combination with components other than acetic acid as a fatty acid forming an ester with cellulose. Good. Further, these triacetylcelluloses may be added with other additives such as other cellulose lower fatty acid esters such as diacetylcellulose, or plasticizers, ultraviolet absorbers, and lubricants as necessary.

  As a cycloolefin polymer base material, the base material which consists of polymers, such as a norbornene-type monomer and a monocyclic cycloolefin monomer, is mentioned, for example.

  Examples of the polycarbonate substrate include aromatic polycarbonate substrates based on bisphenols (bisphenol A and the like), aliphatic polycarbonate substrates such as diethylene glycol bisallyl carbonate, and the like.

  Examples of the acrylic base material include a poly (meth) methyl acrylate base material, a poly (meth) ethyl acrylate base material, and a (meth) methyl acrylate- (meth) butyl acrylate copolymer base material. .

  Examples of the polyester base material include base materials containing at least one of polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate as constituent components.

  Examples of the glass substrate include glass substrates such as soda lime silica glass, borosilicate glass, and alkali-free glass.

  Among these, it is easy to handle the polarizing plate on the surface opposite to the light-transmitting functional layer side of the light-transmitting substrate, and a part of the light-transmitting functional layer is light-transmitted. A triacetyl cellulose base material is preferable because adhesion and the like can be improved by permeating the transparent base material.

  The thickness of the light-transmitting substrate 11 is not particularly limited, but can be 5 μm or more and 100 μm or less. The lower limit of the thickness of the light-transmitting substrate 11 is preferably 15 μm or more from the viewpoint of handling properties, etc., and 25 μm The above is more preferable. The upper limit of the thickness of the light transmissive substrate 11 is preferably 80 μm or less from the viewpoint of thinning.

<< Light-transmissive functional layer >>
The light-transmitting functional layer is a layer intended to exhibit some function in the optical layered body as described above, but in this embodiment, the light-transmitting functional layer 12 exhibits hard coat properties. It is a layer, that is, a hard coat layer. For this reason, the light-transmitting functional layer 12 is a layer having a hardness of “HB” or higher in the pencil hardness test (4.9 N load) defined in JIS K5600-5-4 (1999). By setting the pencil hardness to “HB” or higher, the optical layered body becomes hard and durability can be improved. In addition, from the viewpoint of toughness of the light transmissive functional layer and prevention of curling, the upper limit of the pencil hardness on the surface of the light transmissive functional layer 12 is preferably about 4H.

  The film thickness of the light transmissive functional layer 12 is preferably 1 μm or more and 10 μm or less. If the film thickness of the light transmissive functional layer 12 is in this range, desired hardness can be obtained and the light transmissive functional layer can be made thinner. The film thickness of the light transmissive functional layer can be determined by observing the cross section of the light transmissive functional layer with a scanning electron microscope (SEM). Specifically, using the image of the scanning electron microscope, the film thickness of the three light-transmitting functional layers is measured in one image, this is performed for five images, and the average value of the measured film thickness is calculated. To do.

  The lower limit of the thickness of the light transmissive functional layer 12 is more preferably 8 μm or less from the viewpoint of suppressing cracking of the light transmissive functional layer. The thickness of the light transmissive functional layer 12 is more preferably not less than 0.5 μm and not more than 5.0 μm from the viewpoint of suppressing curling while reducing the thickness of the light transmissive functional layer.

  The refractive index of the light transmissive functional layer 12 may be 1.50 or more and 1.60 or less. The lower limit of the refractive index of the light transmissive functional layer 12 may be 1.52 or more, and the upper limit of the refractive index of the light transmissive functional layer 12 may be 1.56 or less. The refractive index difference between the light transmissive substrate 11 and the light transmissive functional layer 12 is preferably within 0.10, more preferably within 0.06, from the viewpoint of making the interference fringes more invisible. .

  The refractive index of the light-transmitting functional layer 12 can be measured with an Abbe refractometer (NAR-4T manufactured by Atago Co., Ltd.) or an ellipsometer after forming a single layer. Further, as a method for measuring the refractive index after becoming an optical layered body, the light-transmitting functional layer 12 is scraped off with a cutter or the like to prepare a powder sample, and JIS K7142 (2008) B method (powder or granular) The Becke method according to (for transparent material) (using a Cargill reagent with a known refractive index, placing the powder sample on a glass slide, dropping the reagent on the sample, and immersing the sample in the reagent. Observe the state by microscopic observation, and use a method in which the refractive index of the reagent is such that the bright line (Becke line) generated in the sample outline cannot be visually observed due to the difference in refractive index between the sample and the reagent. Can do.

  The light transmissive functional layer 12 can be composed of at least a resin. The light transmissive functional layer 12 may contain a leveling agent and particles in addition to the resin.

<Resin>
Although it does not specifically limit as resin, The thing containing the polymer (cured material, crosslinked material) of a polymeric compound is mentioned. The resin may contain a solvent dry resin in addition to the polymerized polymer. Examples of the polymerizable compound include a polymer (cross-linked product) of an ionizing radiation polymerizable compound and / or a polymer of a thermally polymerizable compound.

  The ionizing radiation polymerizable compound has at least one ionizing radiation polymerizable functional group. In the present specification, the “ionizing radiation polymerizable functional group” is a functional group capable of undergoing a polymerization reaction upon irradiation with ionizing radiation. Examples of the ionizing radiation polymerizable functional group include ethylenically unsaturated groups such as a (meth) acryloyl group, a vinyl group, and an allyl group. In the present specification, “(meth) acryloyl group” means both “acryloyl group” and “methacryloyl group”. Examples of the ionizing radiation include visible light, ultraviolet light, X-rays, electron beams, α rays, β rays, and γ rays.

  Examples of the ionizing radiation polymerizable compound include an ionizing radiation polymerizable monomer, an ionizing radiation polymerizable oligomer, and an ionizing radiation polymerizable prepolymer, and these can be appropriately adjusted and used. As the ionizing radiation polymerizable compound, a combination of an ionizing radiation polymerizable monomer and an ionizing radiation polymerizable oligomer or an ionizing radiation polymerizable polymer is preferable.

(Ionizing radiation polymerizable monomer)
As the ionizing radiation polymerizable monomer, a polyfunctional monomer having two or more ionizing radiation polymerizable functional groups (that is, bifunctional) is preferable. In this specification, the “weight average molecular weight” is a value obtained by dissolving in a solvent such as tetrahydrofuran (THF) and converting to polystyrene by a conventionally known gel permeation chromatography (GPC) method.

  Examples of the bifunctional or higher monomer include trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, and pentaerythritol tri (meth). Acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ditri Methylolpropane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, tripentaerythritol octa (meth) acrylate, Lapentaerythritol deca (meth) acrylate, isocyanuric acid tri (meth) acrylate, isocyanuric acid di (meth) acrylate, polyester tri (meth) acrylate, polyester di (meth) acrylate, bisphenol di (meth) acrylate, diglycerin tetra ( (Meth) acrylate, adamantyl di (meth) acrylate, isoboronyl di (meth) acrylate, dicyclopentane di (meth) acrylate, tricyclodecane di (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, and these are PO, EO And the like modified.

  Among these, from the viewpoint of obtaining a light-transmitting functional layer having high hardness, pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), pentaerythritol tetraacrylate (PETTA), dipentaerythritol pentaacrylate (DPPA), etc. Is preferred.

(Ionizing radiation polymerizable oligomer)
The photopolymerizable oligomer is preferably a bifunctional or higher polyfunctional oligomer. Polyfunctional oligomers include polyester (meth) acrylate, urethane (meth) acrylate, polyester-urethane (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, melamine (meth) acrylate, and isocyanurate (meth). Examples include acrylate and epoxy (meth) acrylate.

(Ionizing radiation polymerizable prepolymer)
The ionizing radiation polymerizable prepolymer has a weight average molecular weight of preferably 10,000 to 80,000, more preferably 10,000 to 40,000. When the weight average molecular weight exceeds 80,000, the viscosity is high, so that the coating suitability is lowered, and the appearance of the obtained optical laminate may be deteriorated. Examples of the polyfunctional prepolymer include urethane (meth) acrylate, isocyanurate (meth) acrylate, polyester-urethane (meth) acrylate, and epoxy (meth) acrylate.

  The thermopolymerizable compound is not particularly limited. For example, phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea cocondensation Examples thereof include resins, silicon resins, polysiloxane resins, and the like.

  The solvent-drying resin is a resin that forms a film only by drying a solvent added to adjust the solid content during coating, such as a thermoplastic resin. When the solvent-drying resin is added, coating defects on the coating surface of the coating liquid can be effectively prevented when forming the light-transmitting functional layer. It does not specifically limit as solvent dry type resin, Generally, a thermoplastic resin can be used.

  Examples of thermoplastic resins include styrene resins, (meth) acrylic resins, vinyl acetate resins, vinyl ether resins, halogen-containing resins, alicyclic olefin resins, polycarbonate resins, polyester resins, polyamide resins. , Cellulose derivatives, silicone resins and rubbers or elastomers.

  The thermoplastic resin is preferably amorphous and soluble in an organic solvent (particularly a common solvent capable of dissolving a plurality of polymers and curable compounds). In particular, from the viewpoint of transparency and weather resistance, styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters, etc.) and the like are preferable.

<Leveling agent>
The leveling agent refers to an additive that prevents defects such as repellency, dents, pinholes, and hulls caused by uneven surface tension of the light-transmitting functional layer and smoothes the surface. The leveling agent is not particularly limited, and is a compound having a polyether group, a polyurethane group, an epoxy group, a carboxyl group, an acrylate group, a methacrylate group, a carbinol group, or a hydroxyl group. The leveling agent may have a polyether group, a polyurethane group, an epoxy group, a carboxyl group, an acrylate group, a methacrylate group, a carbinol group, or a hydroxyl group at the end of the main chain (one end or both ends). You may have in a chain | strand and you may have in the terminal and side chain of a principal chain. The leveling agent is not particularly limited as long as it is a compound having a polyether group, a polyurethane group, an epoxy group, a carboxyl group, an acrylate group, a methacrylate group, a carbinol group, or a hydroxyl group. / Fluorine mixed, acrylic, methacrylic and aromatic leveling agents.

  Among these, a fluorine leveling agent is preferable from the viewpoint of surface tension and leveling properties. Examples of the fluorine leveling agent include F477 and F568 manufactured by DIC.

  It is preferable that content of a leveling agent is 0.01 mass part or more and 5 mass parts or less with respect to 100 mass parts of polymeric compounds in the composition for light transmissive functional layers mentioned later. By setting the content of the leveling agent within this range, the flatness of the surface of the light-transmitting functional layer can be sufficiently ensured.

<Particle>
The particles may be inorganic particles, organic particles, or a mixture thereof. Examples of the inorganic particles include inorganic oxide particles such as silica (SiO ₂ ) particles, alumina particles, titania particles, tin oxide particles, antimony-doped tin oxide (abbreviation: ATO) particles, and zinc oxide particles.

  Examples of the organic particles include plastic particles. Specific examples of the plastic particles include polystyrene particles, melamine resin particles, acrylic particles, acrylic-styrene copolymer particles, silicone particles, benzoguanamine particles, benzoguanamine / formaldehyde condensation particles, polycarbonate particles, and polyethylene particles.

  In order to form the light transmissive functional layer 12 on at least one side of the light transmissive substrate 11, for example, first, the light transmissive functional layer containing at least a polymerizable compound on one surface of the light transmissive substrate 11 is used. Apply the composition. Subsequently, in order to dry the coating-form composition for light transmissive functional layers, it conveys to the zone heated, and the composition for light transmissive functional layers is dried by various well-known methods, and a solvent is evaporated. Then, the composition for light-transmitting functional layers is polymerized (crosslinked) by irradiating the film-shaped composition for light-transmitting functional layers with light such as ultraviolet rays or by applying heat to form a composition for light-transmitting functional layers. Curing is performed to form the light transmissive functional layer 12.

  Examples of the method for applying the light transmissive functional layer composition include known coating methods such as spin coating, dipping, spraying, slide coating, bar coating, roll coating, gravure coating, and die coating. It is done.

  When ultraviolet rays are used as the light for curing the composition for a light-transmitting functional layer, ultraviolet rays emitted from ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, carbon arcs, xenon arcs, metal halide lamps, etc. can be used. . Moreover, as a wavelength of an ultraviolet-ray, the wavelength range of 190-380 nm can be used. Specific examples of the electron beam source include various electron beam accelerators such as a cockcroft-wald type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type.

  You may add the said particle | grain, the said leveling agent, a solvent, and a polymerization initiator to the composition for optically transparent functional layers as needed. Furthermore, the composition for a light-transmitting functional layer includes a conventionally known dispersant, surface active agent, depending on purposes such as increasing the hardness of the light-transmitting functional layer, suppressing curing shrinkage, or controlling the refractive index. Agent, silane coupling agent, thickener, anti-coloring agent, coloring agent (pigment, dye), antifoaming agent, leveling agent, flame retardant, UV absorber, adhesion-imparting agent, polymerization inhibitor, antioxidant, surface A modifier, a lubricant, etc. may be added.

<Solvent>
Examples of the solvent include alcohols (eg, methanol, ethanol, propanol, isopropanol, n-butanol, s-butanol, t-butanol, benzyl alcohol, PGME, ethylene glycol), ketones (acetone, methyl ethyl ketone (MEK), cyclohexanone. , Methyl isobutyl ketone, diacetone alcohol, cycloheptanone, diethyl ketone, etc.), ethers (1,4-dioxane, dioxolane, diisopropyl ether dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic Hydrocarbons (cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl formate, methyl acetate, ethyl acetate, vinegar) Propyl, butyl acetate, ethyl lactate, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, butyl cellosolve, etc.), cellosolve acetates, sulfoxides (dimethylsulfoxide, etc.), amides (dimethylformamide, dimethylacetamide, etc.), or a mixture thereof Is mentioned.

<Polymerization initiator>
The polymerization initiator is a component that is decomposed by light or heat to generate radicals or ionic species to initiate or advance polymerization (crosslinking) of the polymerizable compound.

  The polymerization initiator is not particularly limited, and known ones can be used. Specific examples include, for example, acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime ester, thioxanthones, propiophenone. , Benzyls, benzoins, acylphosphine oxides. In addition, it is preferable to use a mixture of photosensitizers, and specific examples thereof include n-butylamine, triethylamine, poly-n-butylphosphine, and the like.

  As the polymerization initiator, when the polymerizable compound is a compound having an ethylenically unsaturated group, it is preferable to use acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether or the like alone or in combination.

  The content of the polymerization initiator in the composition for light transmissive functional layer is preferably 0.5 parts by mass or more and 10.0 parts by mass or less with respect to 100 parts by mass of the polymerizable compound. By setting the content of the polymerization initiator within this range, the hard coat performance can be sufficiently maintained, and curing inhibition can be suppressed.

  After forming the light transmissive functional layer 12 on one side of the light transmissive substrate 11, as shown in FIG. 1B, a protective film 13 is detachably attached to the surface 12A of the light transmissive functional layer 12. wear. Thereby, the optical laminated body 14 with a protective film can be obtained.

  The protective film 13 includes a base film 15 and an adhesive layer 16 provided on one surface of the base film 15, and the protective film 13 is formed on the surface 12 </ b> A of the light transmitting functional layer 12 by the adhesive layer 16. On the other hand, it can be peeled off. By sticking the protective film 13 to the surface 12A of the light-transmitting functional layer 12, water residue when the optical laminate is subjected to saponification treatment is suppressed, and dirt is attached to the light-transmitting functional layer 12. Can be suppressed.

<< Base film >>
The base film 15 may be light transmissive, but when the optical laminate is incorporated into the display panel, the protective film 13 is peeled off, and thus may not be light transmissive. Although it does not specifically limit as the base film 15, A polyester film (for example, a polyethylene terephthalate film, a polyethylene naphthalate film), a cellulose acylate film (for example, a cellulose triacetate film, a cellulose diacetate film), a polyamide film, a polyimide film, Examples include polyether sulfone film, polysulfone film, polypropylene film, polymethylpentene film, polyvinyl chloride film, polyvinyl acetal film, polyether ketone film, polymethyl methacrylate film, polycarbonate film, polyurethane film and the like. Among these, a polyethylene terephthalate film is preferable from the viewpoint of transparency and handling performance during lamination.

  The thickness of the base film 15 is not particularly limited, but can be 16 μm or more and 100 μm or less, and the lower limit of the thickness of the base film 15 is from the viewpoint of transparency and handling performance at the time of bonding with the optical laminate 10. To 25 μm or more is preferable, and 38 μm or more is more preferable. The upper limit of the thickness of the base film 15 is preferably 50 μm or less from the viewpoint of handling performance at the time of bonding to the optical laminate 10.

<< Adhesive layer >>
The adhesive layer 16 is not particularly limited as long as it has an adhesive function and contains a component that reduces the contact angle of the surface 12A of the light transmissive functional layer 12 with water by peeling off the protective film. The component that reduces the contact angle of the surface 12A of the light-transmitting functional layer 12 with water may be a pressure-sensitive adhesive component, but in this embodiment, a hydrophilic material is added to the pressure-sensitive adhesive layer 16. When the adhesive layer 16 includes a hydrophilic material, the hydrophilic material moves to the surface 12A of the light-transmitting functional layer 12 when the protective film 13 is peeled off, and thereby the contact angle with water can be controlled. .

<Adhesive>
Examples of the adhesive (adhesive resin) constituting the adhesive layer 16 include an acrylic adhesive, a silicone adhesive, a polyester adhesive, a polyurethane adhesive, a polyamide adhesive, a polyvinyl ether adhesive, and vinyl acetate. / Rubber adhesives such as vinyl chloride adhesives, modified polyolefin adhesives, epoxy adhesives, fluorine adhesives, natural rubber, and synthetic rubber can be appropriately selected and used. Among these, an acrylic pressure-sensitive adhesive and a urethane-based pressure-sensitive adhesive are preferable because they have high adhesive strength and transparency and easily deposit a hydrophilic material. Among acrylic adhesives and urethane-based adhesives, the peel strength is relatively small, and it is easy to peel off from the hard coat layer. Since there is no large difference between the refractive index of the layer and the hard coat layer, it is difficult to stand out, the choice of the light transmissive substrate of the protective film can be increased, and a transparent polyethylene terephthalate substrate can be used. From the viewpoint, an acrylic pressure-sensitive adhesive is most preferable.

(Acrylic adhesive)
Examples of the acrylic pressure-sensitive adhesive include an acrylic ester copolymer obtained by copolymerizing an acrylic ester and another monomer. Examples of the acrylate ester include ethyl acrylate, acrylate-n-butyl, acrylate-2-ethylhexyl, isooctyl acrylate, isononyl acrylate, hydroxylethyl acrylate, propylene glycol acrylate, acrylamide, glycidyl acrylate, and the like. Is mentioned. These can be used alone or in combination of two or more. In the present invention, among the acrylate esters, acrylate-n-butyl and acrylate-2-ethylhexyl are preferable in terms of excellent heat resistance, moist heat resistance, durability, and transparency. Other monomers include, for example, methyl acrylate, methyl methacrylate, styrene, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid, itaconic acid, hydroxylethyl acrylate, hydroxylethyl methacrylate, propylene glycol acrylate, acrylamide Methacrylamide, glycidyl acrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, tert-butylaminoethyl methacrylate, and n-ethylhexyl methacrylate. These can be used alone or in combination of two or more.

  The weight average molecular weight (Mw) of the acrylate copolymer used as the acrylic pressure-sensitive adhesive is preferably in the range of 800,000 to 2,000,000, more preferably 1,000,000 to 1,500,000. When the weight average molecular weight is less than 800,000, the adhesive layer becomes soft and sufficiently follows the deformation of the base film, but cannot withstand internal stress repeated under high-temperature and high-humidity long-term conditions. There is a risk of destruction. Moreover, when the weight average molecular weight of an acrylate copolymer exceeds 2 million, there exists a possibility that an adhesion layer may become hard and a float may arise.

(Urethane adhesive)
As a urethane type adhesive, what consists of a urethane resin obtained by making a polyol and a polyisocyanate compound react is mentioned. Examples of the polyol include polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol. Examples of the polyisocyanate compound include diphenylmethane diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, and the like.

<Hydrophilic material>
The hydrophilic material is a material having hydrophilicity. The hydrophilic material is not particularly limited as long as it has hydrophilicity. Examples of the hydrophilic material include materials having a hydrophilic group. Examples of hydrophilic groups include quaternary ammonium bases, hydroxyl groups, carboxyl groups, sulfonyl groups, sulfonic acid groups, phosphoric acid groups, phosphonic acid groups, amino groups, amide groups, carbonyl groups, polyoxymethylene groups, polyoxyethylenes. Group and polyoxypropylene group. Among the hydrophilic materials, an antistatic agent is preferable from the viewpoint of easy precipitation on the surface of the adhesive layer.

(Antistatic agent)
A known antistatic agent can be used as the antistatic agent. Examples of the antistatic agent include cation type antistatic agents having a cationic group such as a quaternary ammonium base, a pyridinium base, and first to third amino groups; a sulfonate group, a sulfate ester base, a phosphate ester base, Anionic antistatic agent having an anionic group such as phosphonate group; amphoteric ion antistatic agent such as amino acid and aminosulfate ester; aminoalcohol and derivatives thereof, glycerin and derivatives thereof, polyethylene glycol and derivatives thereof, etc. Nonionic antistatic agents; conductive polymers; alkali metal salts; ionic liquids and the like. Such an antistatic agent may be used individually by 1 type, and may be used in combination of 2 or more type.

  As a conductive polymer, the high molecular compound (ionic conductive polymer) which has the said cationic group and / or anionic group, and the high molecular compound (electron conductive polymer) which has electronic conductivity are mentioned. Examples of the electron conductive polymer include conductive polyaniline, polyparaphenylene, polyparaphenylene vinylene, polythiophene, polyfuran, polypyrrole, polyselenophene, polyisothianaphthene, polyphenylene sulfide, polyacetylene, polypyridyl vinylene, polyazine, and the like. The high molecular compound of these is mentioned.

Examples of the alkali metal salt include a cation composed of Li ⁺ , Na ⁺ , K ⁺ , Cl ⁻ , Br ⁻ , I ⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , SCN ^−. , ClO ₄ ⁻ , NO ₃ ⁻ , CH ₃ COO ⁻ , C ₉ H ₁₉ COO ⁻ , CF ₃ COO ⁻ , C ₃ F ₇ COO ⁻ , CH ₃ SO ₃ ⁻ , CF ₃ SO ₃ ⁻ , C ₄ F ₉ SO _{^{3 -, C 2 H 5 OSO}} 3 -, C 6 H 13 OSO 3 -, C 8 H 17 OSO 3 -, (CF 3 SO 2) 2 N -, (C 2 F 5 SO 2) 2 N -, ( C ₃ F ₇ SO ₂ ) ₂ N ⁻ , (C ₄ F ₉ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , NbF ₆ ⁻ , TaF ₆ ⁻ , F (HF) _n ⁻ , (CN) ₂ N _{^{-, (CF 3 SO 2)}} (CF 3 CO) N -, (CH 3) 2 PO 4 -, (C 2 H 5) 2 PO 4 -, CH 3 (OC 2 H 4) 2 OSO 3 -, C _A metal salt composed of an anion consisting of ₆ H ₄ (CH ₃ ) SO ₃ ⁻ , (C ₂ F ₅ ) ₃ PF ₃ ⁻ , CH ₃ CH (OH) COO ⁻ , and (FSO ₂ ) ₂ N ⁻ Preferably used.

Specific examples of the alkali metal salt include, for example, LiBr, LiI, LiBF ₄ , LiPF ₆ , LiSCN, LiClO ₄ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO ₂ ) _2. , LiN (FSO ₂ ) ₂ , LiC (CF ₃ SO ₂ ) ₃ , and more preferably LiClO ₄ , LiCF ₃ SO ₃ , LiN (CF ₃ SO ₂ ) ₂ , LiN (C ₂ F ₅ SO _{2) 2, LiN (C 3} F 7 SO 2) 2, LiN (C 4 F 9 SO 2) 2, LiN (FSO 2) 2, LiC (CF 3 SO 2) 3 are used. These alkali metal salts may be used alone or in combination of two or more.

  An ionic liquid refers to a molten salt that is liquid at room temperature (25 ° C.). Examples of the ionic liquid include phosphonium ion, pyridinium ion, pyrrolidinium ion, imidazolium ion, guanidinium ion, ammonium ion, isouronium ion, thiouronium ion, piperidinium ion, pyrazolium ion, sulfonium ion, Cation components such as quaternary ammonium and quaternary phosphonium, and halogen ions, nitrate ions, sulfate ions, phosphate ions, perchlorate ions, thiocyanate ions, thiosulfate ions, sulfite ions, tetrafluoroborate ions, hexafluorophos And substances having an anionic component such as phosphate ion, formate ion, oxalate ion, acetate ion, trifluoroacetate ion, and alkylsulfonate ion. Since the ionic liquid is in a liquid state, it can be easily added and dispersed or dissolved in the pressure-sensitive adhesive as compared with a solid salt. Furthermore, since the ionic liquid has no vapor pressure (non-volatile), it does not disappear over time, and the antistatic property can be continuously obtained.

  Examples of the ionic liquid include 1-allyl-3-methylimidazolium chloride, 1,3-dimethylimidazolium chloride, 1,3-dimethylimidazolium dimethyl phosphate, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium chloride, Ethyl-3-methylimidazolium bromide, 1-ethyl-3-methylimidazolium iodide, 1-ethyl-3-methanesulfonate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methyl Imidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium-p-toluenesulfonate, 1-butyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazolium chloride, 1-methyl-1- Propyl-pyrrolidinium bis (tri Fluoromethanesulfonyl) imide, 1-methyl-1-methylpyrrolidinium bromide, 1-butyl-1-methylpiperidinium bromide, 1-ethylpyridinium chloride, 1-ethylpyridinium bromide, 1-butylpyridinium chloride, 1- Butylpyridinium bromide, 1-butyl-3-methylpyridinium chloride, 1-ethyl-3-methylpyridinium ethyl sulfate, 1-butyl-4-methylpyridinium chloride, 1-butyl-4-methylpyridinium hexafluorophosphate, trimethylpropyl Ammonium bis (trifluoromethanesulfonyl) imide, tributylmethylammonium bis (trifluoromethanesulfonyl) imide, tetrabutylammonium chloride, tetrabutylammonium bromide Cyclohexyl trimethylammonium bis (trifluoromethanesulfonyl Suho) imide, tetrabutyl phosphonium bromide, and the like.

  Among antistatic agents, from the viewpoint of transparency when the antistatic agent is transferred to the light-transmitting functional layer, a quaternary ammonium salt, an ion conductive polymer having a quaternary ammonium base, and a polyethylene glycol-based antistatic agent And one or more antistatic agents selected from the group of amino alcohol-based antistatic agents are preferred.

  The content of the hydrophilic material or antistatic agent in the adhesive layer composition is preferably 2% by mass or more and 30% by mass or less with respect to the adhesive. When the content of the hydrophilic material or the antistatic agent is less than 2% by mass with respect to the pressure-sensitive adhesive, the contact angle with respect to water on the surface of the light-transmitting functional layer after peeling off the protective film does not decrease so much. On the other hand, if it exceeds 30% by mass, the amount of the hydrophilic material or antistatic agent that migrates to the light-transmitting functional layer increases, and there is a risk of contamination. The lower limit of the content of the hydrophilic material or antistatic agent in the adhesive layer composition is more preferably 5% by mass or more with respect to the adhesive, and the upper limit is more preferably 20% by mass or less.

  After the protective film 13 is attached to the light transmissive functional layer 12, the protective film 13 is peeled from the light transmissive functional layer 12, as shown in FIG. Thereby, the contact angle with respect to the water of the surface 12A of the light-transmitting functional layer 12 becomes lower than the contact angle with respect to the water of the surface 12A of the light-transmitting functional layer 12 before the protective film 13 is attached, and FIG. The optical laminated body 10 shown by can be obtained.

  From the viewpoint of wettability when applying a light-transmitting adhesive layer in a subsequent process, the contact angle of the surface 12A of the light-transmitting functional layer 12 with respect to water after peeling of the protective film 13 is the light before the protective film 13 is attached. It is preferably 5 ° or more lower than the contact angle of the surface 12A of the permeable functional layer 12 with water, more preferably 10 ° or more and 30 ° or less. The contact angle with respect to water on the surface of the light-transmitting functional layer can be measured as follows. First, using a contact angle measuring device (product name “Drop Master 500”, manufactured by Kyowa Interface Chemical Co., Ltd.), 1 μL of water was dropped on the surface of the light-transmitting functional layer, and then the contact angle after 10 seconds was 1 second. Ten points are measured at intervals, and the average value is calculated. Then, the same operation is performed three times at different positions, and the contact angle with respect to water is calculated from the average value.

  The contact angle with respect to water on the surface 12A of the light-transmitting functional layer 12 after the protective film 13 is peeled is preferably 20 ° or more and 65 ° or less. If the contact angle with respect to water is 20 ° or more, the liquid curable adhesive layer composition described later will not be too wet and spread out, and there is no possibility of protruding from the surface of the light-transmitting functional layer. On the other hand, when the contact angle with respect to water exceeds 75 °, the liquid curable adhesive layer composition described later may not be wet and spread, but if the contact angle with respect to water is 65 ° or less, the liquid The curable adhesive layer composition can be spread and spread. In addition, when the optical laminate is used for bonding applications, if the contact angle of the hard coat layer surface with water exceeds 65 °, it is necessary to devise post-processing conditions, etc. If the contact angle with respect to water on the surface of the functional layer is 65 ° or less, the selection range of conditions in the subsequent process is widened, so that stable production is easy. The lower limit of the contact angle to water on the surface 12A of the light transmissive functional layer 12 after the protective film 13 is peeled is more preferably 35 ° or more, and the surface 12A of the light transmissive functional layer 12 after the protective film 13 is peeled off. The upper limit of the contact angle with respect to water is more preferably 60 ° or less.

  From the viewpoint of maintaining the transparency of the optical laminate 10, the haze value (%) of the optical laminate 10 after peeling off the protective film 13 is the haze value (%) of the optical laminate before attaching the protective film 13. It is preferable that there is no change. In the present specification, “no change” means that the haze value (%) of the optical laminate after peeling off the protective film is ± 0.5 of the haze value (%) of the optical laminate before attaching the protective film. Means less than%. The haze value shall be measured using a haze meter (product name “HM-150”, manufactured by Murakami Color Research Laboratory) according to JIS K7136: 2000. It is preferable that the haze value (%) of the optical laminate 10 after peeling off the protective film 13 is less than ± 0.3% of the haze value (%) of the optical laminate before attaching the protective film 13.

  When a hydrophilic material such as an antistatic agent is contained in the light-transmitting functional layer itself, if the hydrophilic material is included in the light-transmitting functional layer, the hydrophilic material is collected on the light-transmitting functional layer. However, because the hydrophilic material tries to stabilize, the hydrophilic group of the hydrophilic material faces away from the surface of the light-transmitting functional layer (inside), and the hydrophilic group is the surface of the light-transmitting functional layer. And the contact angle of the light-transmitting functional layer with water does not become lower than expected. In addition, if a hydrophilic material is contained in the light-transmitting functional layer itself, the hydrophilic material may be dispersed non-uniformly, thereby changing the haze value of the optical laminate and reducing the light transmittance. is there. In contrast, in the present embodiment, after the protective film 13 is detachably attached to the surface 12A of the light transmissive functional layer 12, the protective film 13 is peeled from the surface 12A of the light transmissive functional layer 12, Since the contact angle with respect to the water of the surface 12A is lower than the contact angle with respect to the water of the surface 12A of the light-transmitting functional layer 12 before the protective film 13 is attached, the light is smaller than before the protective film 13 is attached. The surface 12A of the permeable functional layer 12 can be hydrophilized. The reason for this is not clear, but when the protective film is peeled from the light-transmitting functional layer, hydrophilic components (for example, antistatic agents) in the adhesive layer of the protective film are deposited on the surface of the light-transmitting functional layer. It is considered that the presence of this component on the surface of the light-transmitting functional layer decreases the contact angle with water on the surface of the light-transmitting functional layer, thereby improving the hydrophilicity. Further, after the protective film 13 is detachably attached to the surface 12A of the light-transmitting functional layer 12, the protective film 13 is peeled from the surface 12A of the light-transmitting functional layer 12, whereby the contact angle of the surface 12A with respect to water. Can be made lower than the contact angle with respect to water of the surface 12A of the light-transmitting functional layer 12 before the protective film 13 is attached, so that the contact angle with respect to water on the surface 12A of the light-transmitting functional layer 12 is controlled. Is possible. In general, since the protective film is for protecting the surface of the light transmissive functional layer, when the protective film is peeled off, the component of the adhesive layer does not adhere to the surface of the light transmissive functional layer. It is technical common sense that is not preferable. Therefore, the effect of the present invention that the contact angle with water on the surface of the light-transmitting functional layer is lowered by intentionally adhering the components of the adhesive layer to the surface of the light-transmitting functional layer is an effect unexpected by those skilled in the art. It can be said that there is.

  Conventionally, a protective film may be attached to the surface of the light-transmitting functional layer before the saponification treatment. In this embodiment, the surface of the light-transmitting functional layer 12 is utilized using the protective film 13. Since the contact angle of 12A with respect to water is controlled, a special member or the like is not required, and the contact angle with respect to water on the surface 12A of the light-transmitting functional layer 12 can be reduced by a simple method.

  When the light-transmitting functional layer contains a leveling agent, the flatness of the surface of the light-transmitting functional layer is improved, but the contact angle with water on the surface of the light-transmitting functional layer tends to increase. On the other hand, according to this embodiment, since the contact angle with respect to the water of the surface 12A of the light transmissive functional layer 12 is controlled using the protective film 13, the light transmissive functional layer 12 uses a leveling agent. Even if it is included, the contact angle with respect to water on the surface 12A of the light transmissive functional layer 12 can be reduced. Thereby, the contact angle with respect to water can be reduced while maintaining the flatness of the surface 12A of the light-transmitting functional layer 12.

  According to this embodiment, when the antistatic agent is included in the adhesive layer 16, the contact angle with respect to water on the surface 12A of the light-transmitting functional layer 12 is greater than when other hydrophilic materials are included. Can be further reduced. That is, the antistatic agent has a tendency to deposit on the surface more than other hydrophilic materials. For this reason, when an antistatic agent is contained in the pressure-sensitive adhesive layer, the antistatic agent is likely to be deposited on the surface of the pressure-sensitive adhesive layer, so that there is a high possibility that it will migrate to the surface of the light-transmitting functional layer. Thereby, when the antistatic agent is contained in the pressure-sensitive adhesive layer 16, the contact angle with respect to water on the surface 12A of the light-transmitting functional layer 12 can be further reduced as compared with the case where other hydrophilic materials are contained. Can do.

  Since the antistatic agent is a material often used in the optical field, the antistatic agent contained in the pressure-sensitive adhesive layer 16 is manufactured rather than the hydrophilic material that is not frequently used in the optical field. Easy to manage in the process. In addition, when an antistatic agent is included in the adhesive layer 16, charging when the protective film 13 is peeled can be suppressed.

  Such an optical layered body can be used by being incorporated into an image display device with a touch panel, for example. FIG. 3 is a schematic configuration diagram of an image display device with a touch panel.

<<< Image display device with touch panel >>>
As shown in FIG. 3, the image display device 20 with a touch panel mainly includes a display panel 30 for displaying an image, a backlight device 40 disposed on the back side of the display panel 20, and the display panel 30. Are also provided with a touch panel 50 disposed on the viewer side and a light-transmitting adhesive layer 60 interposed between the display panel 30 and the touch panel 50. In the present embodiment, since the display panel 30 is a liquid crystal display panel, the display device 20 with a touch panel includes the backlight device 40. However, depending on the type of the display panel (display element), the backlight device 40 is provided. Not necessary.

<< Display panel >>
As shown in FIG. 3, the display panel 30 includes a protective film 31 such as a triacetyl cellulose film (TAC film), a polarizing element 32, a retardation film 33, and a transparent film from the backlight device 40 side toward the viewer side. The adhesive layer 34, the display element 35, the transparent adhesive layer 36, the retardation film 37, the polarizing element 38, and the optical laminate 10 are laminated in this order. The display panel 30 only needs to include the display element 35 and the optical laminated body 10 disposed closer to the viewer than the display element 35, and may not include the protective film 31 or the like.

  Examples of the retardation films 33 and 37 include a triacetyl cellulose film and a cycloolefin polymer film. The retardation film 37 may be the same as the protective film 31. Examples of the transparent pressure-sensitive adhesive constituting the transparent pressure-sensitive adhesive layers 34 and 36 include a pressure-sensitive adhesive (PSA).

  The display element 35 is a liquid crystal display element. However, the display element is not limited to the liquid crystal display element, and may be, for example, an organic EL display element. In the liquid crystal display element, a liquid crystal layer, an alignment film, an electrode layer, a color filter, and the like are disposed between two glass substrates.

  Examples of the polarizing element 38 include a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, and an ethylene-vinyl acetate copolymer saponified film that are dyed and stretched with iodine or the like. When laminating the optical layered body 10 and the polarizing element 38, it is preferable to saponify the optical layered body 10 in advance. By subjecting the optical laminate 10 to a saponification treatment, the adhesiveness is improved and an antistatic effect can be obtained.

  The optical laminated body 10 is disposed on the viewer side with respect to the display element 35, and the light transmissive functional layer 12 is disposed on the viewer side with respect to the light transmissive substrate 11. The surface on the viewer side of the optical laminate 10 (the surface 12A of the light transmissive functional layer 12) is in contact with the light transmissive adhesive layer 60.

<< Backlight device >>
The backlight device 40 illuminates the display panel 30 from the back side of the display panel 30. As the backlight device 40, a known backlight device can be used, and the backlight device 40 may be either an edge light type or a direct type backlight device.

<< Touch panel >>
The touch panel 50 includes a sensor unit 70, a cover glass 80 disposed closer to the viewer than the sensor unit 70, and a transparent adhesive layer 81 for fixing the sensor unit 70 and the cover glass 80. The touch panel 50 only needs to include the sensor unit 70, and may not include the cover glass 80 and the transparent adhesive layer 81.

<Sensor part>
The sensor unit 70 is a part that functions as a sensor of the touch panel 50. Although it does not specifically limit as the sensor part 70, For example, the sensor used for a projection capacitive system is mentioned. 3 includes a base film 71 provided with a patterned conductive layer 72 and a base film 71 provided with a patterned conductive layer 73 via a transparent adhesive layer 74. It has a laminated structure.

(Base film)
A base film 71 shown in FIG. 3 includes a light transmissive base 75, a hard coat layer 76 provided on one surface of the light transmissive base 75, and a high coat provided on the hard coat layer 76. A refractive index layer 77, a low refractive index layer 78 provided on the high refractive index layer 77, and a hard coat layer 79 laminated on the other surface of the transparent substrate 75 are provided.

  Instead of the substrate film 71, a light-transmitting substrate, a hard coat layer provided on one surface of the light-transmitting substrate, a high refractive index layer provided on the hard coat layer, and a high refraction A low refractive index layer provided on the refractive index layer, a hard coat layer provided on the other surface of the light-transmitting substrate, a high refractive index layer provided on the hard coat layer, and the high refractive index You may use the base film provided with the low-refractive-index layer laminated | stacked on the layer. In this case, patterned conductive layers are provided on the low refractive index layers present on both sides of the base film.

  As the light transmissive substrate 75, the hard coat layers 76 and 79, the high refractive index layer 77, and the low refractive index layer 78, a light transmissive substrate, a hard coat layer, and a high refractive index that are used in a normal touch panel sensor. Since a refractive index layer and a low refractive index layer can be used, description thereof will be omitted here.

(Conductive layer)
The shape of the conductive layers 72 and 73 is not particularly limited, and examples thereof include a square shape and a stripe shape. The conductive layers 72 and 73 are connected to a terminal portion (not shown) through an extraction pattern (not shown). Although the conductive layers 72 and 73 have shown the example comprised from the transparent conductive material, a conductive layer can be comprised from a mesh-shaped conducting wire. Transparent conductive materials include tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO), zinc oxide, indium oxide (In ₂ O ₃ ), aluminum-doped zinc oxide (AZO), gallium-doped zinc oxide (GZO), oxidation Examples thereof include metal oxides such as tin, zinc oxide-tin oxide, indium oxide-tin oxide, and zinc oxide-indium oxide-magnesium oxide. Examples of the conductive wire material include light-shielding metal materials such as silver, copper, aluminum, and alloys thereof.

  The film thicknesses of the conductive layers 72 and 73 are appropriately set according to the electrical resistance specifications, but are preferably 10 nm or more and 50 nm or less, for example.

  The formation method of the conductive layers 72 and 73 is not particularly limited, and a sputtering method, a vacuum deposition method, an ion plating method, a CVD method, a coating method, a printing method, or the like can be used. Examples of the method for patterning the conductive layer include a photolithography method.

  When the conductive layer is composed of a mesh-like conductor, the width of the conductor is preferably 1 μm or more and 20 μm or less, and more preferably 2 μm or more and 15 μm or less. As a result, the influence of the conducting wire on the image visually recognized by the observer can be reduced to a negligible level.

  When the conductive layer is composed of a mesh-like conductor, the conductive layer has, for example, a rectangular opening formed by the conductor. The aperture ratio of the conductive layer is appropriately set according to the characteristics of the image light emitted from the display device, and is in the range of 80% to 90%, for example. Further, the arrangement pitch of the openings is appropriately set within a range of 100 μm or more and 1000 μm or less in accordance with the required aperture ratio and the value of the conductor width.

<< light transmissive adhesive layer >>
The light transmissive adhesive layer 60 is interposed between the display panel 30 and the touch panel 50 and bonded to both the display panel 30 and the touch panel 50. Thereby, the display panel 30 and the touch panel 50 are fixed. The light transmissive adhesive layer 60 is composed of a cured product of a liquid curable adhesive layer composition (for example, OCR: optically clear resin) containing a polymerizable compound.

  When fixing the display panel 30 and the touch panel 50 with the light-transmitting adhesive layer 60, first, a liquid curable adhesive layer composition is applied to the surface 12A of the light-transmitting functional layer 12 and cured. The coating film of the composition for adhesive adhesive layers is formed. Next, the coating film of the composition for curable adhesive layer is irradiated with light through the touch panel 50 or heat is applied to cure the coating film. Thus, the light transmissive adhesive layer 60 is formed, and the display panel 30 and the touch panel 50 are integrated and fixed via the light transmissive adhesive layer 60.

  The film thickness of the light transmissive adhesive layer 60 is preferably 30 μm or more and 300 μm or less. If the film thickness of the light-transmitting adhesive layer 60 is within this range, the luminance of the image display device can be improved while ensuring adhesion. The film thickness of the light transmissive adhesive layer can be determined by observing the cross section of the light transmissive adhesive layer with a scanning electron microscope (SEM). Specifically, using a scanning electron microscope image, measure the film thickness of the light-transmitting adhesive layer at three locations in one image, perform this for five images, and calculate the average value of the measured film thickness To do.

  In order to describe the present invention in detail, examples will be described below, but the present invention is not limited to these descriptions. In addition, the following “100% solid content conversion value” is a value when the solid content in the solvent diluted product is 100%.

<Composition for hard coat layer>
First, each component was mix | blended so that it might become the composition shown below, and the composition for hard-coat layers etc. were obtained.
(Composition 1 for hard coat layer)
-Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (product name "KAYARAD DPHA", manufactured by Nippon Kayaku Co., Ltd.): 100 parts by mass-Polymerization initiator (product name "Irgacure 184", manufactured by BASF Japan): 4 parts by mass / leveling agent (product name “F-568”, manufactured by DIC): 0.5 parts by mass (100% solid content conversion value)
Mixture of methyl isobutyl ketone (MIBK) and methyl ethyl ketone (MEK) (MIBK / MEK = 50/50): 156.8 parts by mass

(Composition 2 for hard coat layer)
-Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (product name "KAYARAD DPHA", manufactured by Nippon Kayaku Co., Ltd.): 100 parts by mass-polymerization initiator (product name "Irgacure 184", manufactured by BASF Japan): 4 parts by mass / leveling agent (product name “FTX-681”, manufactured by Neos): 0.5 parts by mass (100% solid content conversion value)
Mixture of methyl isobutyl ketone (MIBK) and methyl ethyl ketone (MEK) (MIBK / MEK = 50/50): 156.8 parts by mass

(Composition 3 for hard coat layer)
-Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (product name "KAYARAD DPHA", manufactured by Nippon Kayaku Co., Ltd.): 100 parts by mass-Polymerization initiator (product name "Irgacure 184", manufactured by BASF Japan): 4 parts by mass and leveling agent (product name “10-301”, manufactured by Dainichi Seika Kogyo Co., Ltd.): 0.5 parts by mass (100% solid content conversion value)
Mixture of methyl isobutyl ketone (MIBK) and methyl ethyl ketone (MEK) (MIBK / MEK = 50/50): 156.8 parts by mass

(Composition 4 for hard coat layer)
-Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (product name "KAYARAD DPHA", manufactured by Nippon Kayaku Co., Ltd.): 100 parts by mass-Polymerization initiator (product name "Irgacure 184", manufactured by BASF Japan): 4 parts by mass / leveling agent (product name “F-568”, manufactured by DIC): 0.5 parts by mass (100% solid content conversion value)
・ Antistatic agent (Product name “REC-SM-39”, manufactured by Regige Color Kogyo Co., Ltd.): 0.02 mass%
Mixture of methyl isobutyl ketone (MIBK) and methyl ethyl ketone (MEK) (MIBK / MEK = 50/50): 156.8 parts by mass

<Adhesive layer composition>
The composition for adhesion layers was obtained in the procedure shown below.
(Composition 1 for adhesive layer)
In a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas inlet tube, and a condenser, 200 parts by mass of 2-ethylhexyl acrylate, 8 parts by mass of 2-hydroxyethyl acrylate, and 2,2′-azobis as a polymerization initiator Charge 0.4 parts by weight of isobutyronitrile and 312 parts by weight of ethyl acetate, introduce nitrogen gas while gently stirring, and perform a polymerization reaction for 6 hours while maintaining the liquid temperature in the flask at around 65 ° C. A polymer solution (A) (40% by mass) was prepared.

  On the other hand, in a four-necked flask equipped with a stirring blade, a thermometer, and a cooler, 5 parts by mass of an alicyclic ionic liquid (manufactured by Guangei Chemical Industry Co., Ltd., liquid at 25 ° C.), nonionic charging Charge 5 parts by weight of inhibitor (product name “ADEKA rear soap ER-10”, manufactured by ADEKA) and 90 parts by weight of ethyl acetate, and mix and stir the liquid temperature in the flask at 25 ° C. for about 1 hour to prevent static charge. An agent solution (a) (10% by mass) was prepared.

  The acrylic polymer solution (A) is diluted to 20% by mass with ethyl acetate, 100 parts by mass of this solution is mixed with 1 part by mass of the antistatic agent solution (a), and isocyanurate of hexamethylene diisocyanate as a cross-linking agent (Japan). Polyurethane Kogyo Co., Ltd., Coronate HX) 0.35 parts by mass and dibutyltin dilaurate (1% by mass ethyl acetate solution) 0.4 parts by mass as a crosslinking catalyst were added and mixed and stirred at 25 ° C. for about 1 minute. An adhesive composition 1 as an adhesive solution was prepared.

(Adhesive layer composition 2)
In the adhesive layer composition 2, the adhesive layer was adhered in the same manner as the adhesive layer composition 1 except that the antistatic agent solution (b) prepared by the following preparation was used instead of the antistatic agent solution (a). Layer composition 2 was obtained.

A four-flask equipped with a stirring blade, a thermometer, and a condenser was charged with 5 parts by weight of a fluorine-containing lithium imide salt (LiN (C ₂ F ₅ SO ₂ ) ₂ ) and 20 parts by weight of ethyl acetate, and nitrogen was stirred gently. Gas was introduced, and the mixture was stirred for about 2 hours while maintaining the liquid temperature in the flask at around 25 ° C. to prepare an antistatic agent solution (b) (20 wt%).

(Adhesive layer composition 3)
In the adhesive layer composition 3, except that an ionic liquid (product name “FC-4400”, manufactured by 3M Company) was used instead of the antistatic agent solution (a), the adhesive layer composition 1 and Similarly, the composition 3 for the adhesion layer was obtained.

(Adhesive layer composition 4)
In the adhesive layer composition 4, an adhesive layer was used except that a quaternary ammonium base-containing polymer (product name “1SX-1048I”, manufactured by Taisei Fine Chemical Co., Ltd.) was used instead of the antistatic agent solution (a). In the same manner as for Composition 1, an adhesive layer composition 4 was obtained.

(Adhesive layer composition 5)
In the adhesive layer composition 5, the adhesive layer composition 4 was prepared in the same manner as the adhesive layer composition 1 except that the antistatic agent solution (a) contained in the adhesive composition 1 was not used. Obtained.

<Example 1>
First, a 60 μm-thick triacetyl cellulose film (product name “TD60UL”, manufactured by FUJIFILM Corporation) is prepared as a light-transmitting substrate, and the hard coat layer composition 1 is applied to one side of the triacetyl cellulose film. A coating film was formed. Next, 50 ° C. dry air was passed through the formed coating film at a flow rate of 0.5 m / s for 15 seconds, and then 70 ° C. dry air was passed through for 30 seconds at a flow rate of 10 m / s. By evaporating the solvent in the coating film, the film is cured by irradiating ultraviolet rays with a cumulative light quantity of 100 mJ / cm ² under a nitrogen atmosphere (oxygen concentration of 200 ppm or less), thereby transmitting light. A hard coat layer having a thickness of 5 μm (when cured) was formed as a functional layer.

  On the other hand, a biaxially stretched polyethylene terephthalate film having a thickness of 38 μm was prepared, and the adhesive layer composition 1 was applied to one side of the biaxially stretched polyethylene terephthalate film. And it dried at 100 degreeC for 2 minute (s), the 20-micrometer-thick adhesion layer was formed, and this formed the protective film.

  Subsequently, the protective film was affixed so that the hard-coat layer and the adhesion layer might closely_contact | adhere to the surface on the opposite side to the surface on the triacetyl cellulose film side in a hard-coat layer. This produced the optical laminated body with a protective film. Finally, the protective film was peeled off from the surface of the hard coat layer to obtain an optical laminate.

<Example 2>
In Example 2, an optical laminate was produced in the same manner as in Example 1 except that the adhesive layer composition 2 was used instead of the adhesive layer composition 1.

<Example 3>
In Example 3, an optical laminate was produced in the same manner as in Example 1 except that the adhesive layer composition 3 was used instead of the adhesive layer composition 1.

<Example 4>
In Example 4, an optical laminate was produced in the same manner as in Example 1 except that the adhesive layer composition 4 was used instead of the adhesive layer composition 1.

<Example 5>
In Example 5, an optical laminate was produced in the same manner as in Example 1 except that the hard coat layer composition 2 was used instead of the hard coat layer composition 1.

<Example 6>
In Example 6, an optical laminate was prepared in the same manner as in Example 5 except that the adhesive layer composition 2 was used instead of the adhesive layer composition 1.

<Example 7>
In Example 7, an optical laminate was produced in the same manner as in Example 5 except that the adhesive layer composition 3 was used instead of the adhesive layer composition 1.

<Example 8>
In Example 8, an optical laminate was produced in the same manner as in Example 5 except that the adhesive layer composition 4 was used instead of the adhesive layer composition 1.

<Example 9>
In Example 9, an optical laminate was produced in the same manner as in Example 1 except that the hard coat layer composition 3 was used instead of the hard coat layer composition 1.

<Example 10>
In Example 10, an optical laminate was produced in the same manner as in Example 9, except that the adhesive layer composition 2 was used instead of the adhesive layer composition 1.

<Example 11>
In Example 11, an optical laminate was produced in the same manner as in Example 9 except that the adhesive layer composition 3 was used instead of the adhesive layer composition 1.

<Example 12>
In Example 12, an optical laminate was produced in the same manner as in Example 9 except that the adhesive layer composition 4 was used instead of the adhesive layer composition 1.

<Example 13>
In Example 13, an optical laminate was produced in the same manner as in Example 1 except that the hard coat layer composition 4 was used instead of the hard coat layer composition 1.

<Example 14>
In Example 14, an optical laminate was produced in the same manner as in Example 13 except that the adhesive layer composition 2 was used instead of the adhesive layer composition 1.

<Example 15>
In Example 15, an optical laminate was produced in the same manner as in Example 13 except that the adhesive layer composition 3 was used instead of the adhesive layer composition 1.

<Example 16>
In Example 16, an optical laminate was produced in the same manner as in Example 13 except that the adhesive layer composition 4 was used instead of the adhesive layer composition 1.

<Comparative Example 1>
In Comparative Example 1, an optical laminate was produced in the same manner as in Example 1 except that the adhesive layer composition 5 was used instead of the adhesive layer composition 1.

<Comparative example 2>
In Comparative Example 2, an optical laminate was produced in the same manner as Comparative Example 1, except that Hard Coat Layer Composition 2 was used instead of Hard Coat Layer Composition 1.

<Comparative Example 3>
In Comparative Example 3, an optical laminate was produced in the same manner as Comparative Example 1 except that the hard coat layer composition 3 was used instead of the hard coat layer composition 1.

<Comparative Example 4>
In Comparative Example 4, an optical laminate was produced in the same manner as Comparative Example 1 except that the hard coat layer composition 4 was used instead of the hard coat layer composition 1.

<Measurement of contact angle to water>
In the optical laminates obtained in Examples and Comparative Examples, the contact angle with respect to water was measured as follows. Specifically, the contact angle measuring device (product name “Drop Master500”, manufactured by Kyowa Interface Chemical Co., Ltd.) is used in the optical laminate before the protective film is attached and the optical laminate after the protective film is peeled off. Each 1 μL of water was dropped on the surface of the hard coat layer, and 10 contact angles after 10 seconds were measured at 1 second intervals, and the average value thereof was calculated. The same operation was performed three times at different positions, and the contact angle with water was calculated from the average value.

<Appearance evaluation>
In the optical laminates obtained in Examples and Comparative Examples, the haze value is measured, and the optical laminate after peeling off the protective film has a changed haze value compared to the optical laminate before attaching the protective film. Whether or not the surface of the hard coat layer in the optical laminate after peeling off the protective film was visually observed and evaluated. The evaluation criteria were as follows. The haze value is measured using a haze meter (product name “HM-150”, manufactured by Murakami Color Research Laboratory) according to JIS K7136: 2000, and the haze value (%) of the optical layered product after the protective film is peeled off. Is less than ± 0.5% of the haze value (%) of the optical laminate prior to attaching the protective film, the change in haze value was not confirmed, and the optical laminate after peeling off the protective film If the haze value (%) was changed by ± 0.5% or more of the haze value (%) of the optical layered body before the protective film was attached, the change in the haze value was confirmed.
◯: No change in haze value, defects such as appearance stains, and no decrease in flatness were confirmed.
Δ: Some changes in haze value, defects such as stains on appearance, and a decrease in flatness were confirmed, but they were at a level causing no practical problems.
X: Defects such as change in haze value, appearance stains, and deterioration in flatness were clearly confirmed.

The results are shown in Table 1.

  In the optical laminates according to Comparative Examples 1 to 4, the contact angle to water is the same before the protective film is applied and after the protective film is peeled off, or after the protective film is peeled off before the protective film is applied. The contact angle to water was higher. On the other hand, in the optical laminated body which concerns on Examples 1-16, the direction after peeling of a protective film was lower than the direction before sticking a protective film. Thereby, according to the optical laminated body which concerns on Examples 1-16, it was confirmed that hydrophilicity can be improved more.

  Further, in the optical laminates according to Examples 1 to 16, no change in haze value, defects such as appearance stains and flatness reduction were confirmed, or a change in haze value, defects such as appearance stains and flatness reduction. However, since it was a level that had no problem in practical use, even if the hard coat layer contained a leveling agent without affecting the transparency, the hard film after peeling off the protective film It was confirmed that the contact angle to water can be reduced while maintaining the flatness of the surface of the coat layer.

  In the optical laminates according to Examples 1 to 8, 11, and 13 to 16, since the contact angle with respect to water on the surface of the hard coat layer after peeling of the protective film was 65 ° or less, particularly for the curable adhesive layer Since the composition was hardly repelled and the selection range of processing conditions in the subsequent process was widened, the composition could be manufactured more stably and was particularly excellent.

DESCRIPTION OF SYMBOLS 10 ... Optical laminated body 11 ... Light transmissive base material 12 ... Light transmissive functional layer 13 ... Protective film 14 ... Optical laminated body 15 with a protective film ... Base film 16 ... Adhesive layer 20 ... Image display apparatus 30 with a touch panel ... Display Panel 35 ... Display element 40 ... Backlight device 50 ... Touch panel 60 ... Light transmissive adhesive layer

Claims (15)

Forming a light transmissive functional layer on at least one side of the light transmissive substrate;
A step of attaching a protective film including a base film and an adhesive layer provided on one surface of the base film to the surface of the light-transmitting functional layer so as to be peelable by the adhesive layer;
The protective film is peeled from the light-transmitting functional layer, and the contact angle with respect to water of the surface of the light-transmitting functional layer after peeling of the protective film is the light-transmitting function before the protective film is attached. And a step of obtaining a light-transmitting functional layer having a lower contact angle with respect to water on the surface of the layer.   The contact angle with respect to water on the surface of the light transmissive functional layer after peeling of the protective film is 5 ° or more lower than the contact angle with respect to water on the surface of the light transmissive functional layer before application of the protective film. The manufacturing method of the optical laminated body of 1.   The manufacturing method of the optical laminated body of Claim 1 whose contact angle with respect to the water of the surface of the said light-transmitting functional layer after peeling of the said protective film is 20 degrees or more and 65 degrees or less.   The manufacturing method of the optical laminated body of Claim 1 with which the said adhesion layer contains a hydrophilic material.   The manufacturing method of the optical laminated body of Claim 1 in which the said adhesion layer contains an antistatic agent. A water contact angle control method for an optical laminate that controls a contact angle with respect to water of an optical laminate comprising a light transmissive substrate and a light transmissive functional layer provided on at least one side of the light transmissive substrate. There,
A protective film comprising a base film and an adhesive layer provided on one surface of the base film on the surface of the light-transmitting functional layer formed on at least one side of the light-transmitting base material. And a process of applying a peelable by,
The protective film is peeled from the light-transmitting functional layer, and the contact angle with respect to water on the surface of the light-transmitting functional layer after the protective film is peeled off is the light-transmitting functional layer before the protective film is attached. A method for controlling the water contact angle of an optical laminate, comprising the step of lowering the contact angle of water on the surface of the optical laminate.   The contact angle with respect to water on the surface of the light transmissive functional layer after peeling of the protective film is 5 ° or more lower than the contact angle with respect to water on the surface of the light transmissive functional layer before application of the protective film. 6. A method for controlling a water contact angle of an optical laminate according to 6.   The water contact angle control method for an optical laminate according to claim 6, wherein a contact angle of water on the surface of the light transmissive functional layer after peeling of the protective film is 20 ° or more and 65 ° or less.   The water contact angle control method for an optical laminate according to claim 6, wherein the adhesive layer contains a hydrophilic material.   The method for controlling a water contact angle of an optical laminate according to claim 6, wherein the adhesive layer contains an antistatic agent. An optical laminate with a protective film comprising an optical laminate and a protective film that is detachably attached to the optical laminate,
The optical laminate comprises a light transmissive substrate and a light transmissive functional layer provided on at least one side of the light transmissive substrate,
The protective film includes a base film, and an adhesive layer provided on one surface of the base film and attached to the surface of the light transmissive functional layer,
When the protective film is peeled from the optical layered body, the contact angle with respect to water on the surface of the light transmissive functional layer after peeling of the protective film is the light transmissive functional layer before application of the protective film. The optical laminated body with a protective film lower than the contact angle with respect to the surface of water of water.   The contact angle with respect to water on the surface of the light transmissive functional layer after peeling of the protective film is 5 ° or more lower than the contact angle with respect to water on the surface of the light transmissive functional layer before application of the protective film. The optical laminated body with a protective film of 11.   The optical laminated body with a protective film of Claim 11 whose contact angle with respect to the water of the surface of the said light-transmitting functional layer after peeling of the said protective film is 20 degrees or more and 65 degrees or less.   The optical laminated body with a protective film of Claim 11 in which the said adhesion layer contains a hydrophilic material.   The optical laminated body with a protective film of Claim 11 in which the said adhesion layer contains an antistatic agent.

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