JP2017217779A - 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 method for controlling a contact angle of an optical laminate with water, by which a contact angle of a surface of a hard coat layer with water can be controlled to 65° or more, and an optical laminate with a protective film.SOLUTION: A method for controlling a contact angle of an optical laminate 10 with water is provided, which includes: a step of removably sticking a protective film 13 having a base film 15 and an adhesive layer 16 containing a water contact angle increasing material to a surface 12A of a hard coat layer 12 formed on at least one surface side of a light-transmitting substrate 11, with the adhesive layer 16; and a step of removing the protective film 13 from the hard coat layer 12 so as to increase the contact angle of the surface 12A of the hard coat layer 12 with water after removing the protective film 13 to be greater than a contact angle with water of the surface 12A of the hard coat layer 12 before sticking the protective film 13, obtaining the contact angle of 65° or greater with water of the surface 12A of the hard coat layer 12 after removing the protective film 13.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a water contact angle control method for an optical laminate 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 the image display device with a direct bonding type touch panel, the display panel and the touch panel are fixed with a light-transmitting adhesive layer, but when forming the light-transmitting adhesive layer, a liquid curable liquid having hydrophilicity. An adhesive layer composition is often used. Considering the wettability with respect to the curable adhesive layer composition, the contact angle of water on the surface of the hard coat layer constituting the surface of the display panel is required to be low.

  On the other hand, when the hard coat layer is used not for bonding but for a clear hard coat layer provided near the surface of the image display device, the contact angle with water is 65 ° or more from the viewpoint of antifouling property and the like. It is required to be.

  Since the contact angle of water on the surface of the hard coat layer for bonding use is low, a hard coat layer different from the bonding use is currently used in the clear hard coat layer use. However, even a hard coat layer for bonding can be used as a clear hard coat layer if the contact angle with water on the surface of the hard coat layer can be increased.

  The present invention has been made to solve the above problems. That is, to provide a water contact angle control method for an optical laminate and an optical laminate with a protective film capable of increasing the contact angle of water on the surface of the hard coat layer with the contact angle being 65 ° or more. With the goal.

  According to one aspect of the present invention, an optical laminate that controls a contact angle with respect to water of an optical laminate comprising a light transmissive substrate and a hard coat layer provided on at least one side of the light transmissive substrate. A method for controlling a water contact angle of a body, provided on a surface of a hard coat layer formed on at least one side of a light-transmitting substrate, provided on one surface of the substrate film and the substrate film, and A step of attaching a protective film including an adhesive layer containing a water contact angle increasing material that increases the contact angle of water on the surface of the hard coat layer to the peelable layer, and peeling the protective film from the hard coat layer Then, the contact angle of water on the surface of the hard coat layer after peeling of the protective film is the contact angle of water on the surface of the hard coat layer before application of the protective film. Ri be increased, and a step of the contact angle 65 ° or more with respect to water of the surface of the hard coat layer after peeling of the protective film, the water contact angle control method of the optical laminate is provided.

  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 hard coat 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, A water contact angle increasing material that increases the contact angle of water on the surface of the coat layer, and an adhesive layer attached to the surface of the hard coat layer, and when the protective film is peeled off from the optical laminate The contact angle of water on the surface of the hard coat layer after peeling of the protective film is larger than the contact angle of water on the surface of the hard coat layer before application of the protective film. And the contact angle is 65 ° or more with respect to water of the surface of the hard coat layer after peeling of the protective film, the protective film-attached optical laminate is provided.

  According to the method for controlling the water contact angle of the optical layered body of one aspect of the present invention, the adhesive layer contains a water contact angle increasing material that increases the contact angle of the surface of the hard coat layer with water. When the film is peeled off, the contact angle with water on the surface of the hard coat layer after peeling of the protective film becomes larger than the contact angle with respect to water on the surface of the hard coat layer before application of the protective film, and the protective film is peeled off. The contact angle of water on the surface of the hard coat layer later can be made 65 ° or more.

  According to the optical laminate with a protective film of another aspect of the present invention, since the adhesive layer includes a water contact angle increasing material that increases the contact angle of the hard coat layer with water, the protective film is peeled from the optical laminate. When the protective film is peeled off, the water contact angle on the surface of the hard coat layer after peeling off the protective film can be made larger than the contact angle on the surface of the hard coat layer on the surface before sticking the protective film. The contact angle of water on the surface of the hard coat layer later can be made 65 ° or more.

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, a water contact angle control method for an optical laminate and an optical laminate with a protective film according to an embodiment of the present invention will be described with reference to the 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.

<<< Method for controlling water contact angle of optical laminate and optical laminate with protective film >>>
First, as shown in FIG. 1A, an optical laminate including a light transmissive substrate 11 and a hard coat layer 12 formed on at least one side of the light transmissive substrate 11 is prepared.

<< 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 hard coat layer side of the light-transmitting substrate, and a part of the hard coat layer is light-transmitting substrate. A triacetylcellulose base material is preferable because adhesion and the like can be improved by permeating into the 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.

<< Hard coat layer >>
The hard coat layer 12 is a layer having a hardness of “H” or higher in a pencil hardness test (4.9 N load) defined by JIS K5600-5-4 (1999). By setting the pencil hardness to “H” or higher, the optical layered body becomes hard and durability can be improved. In addition, from the viewpoint of toughness of the hard coat layer and prevention of curling, the upper limit of the pencil hardness on the surface of the hard coat layer 12 is preferably about 4H.

  The film thickness of the hard coat layer 12 is preferably 1 μm or more and 10 μm or less. If the film thickness of the hard coat layer 12 is in this range, it is possible to obtain a desired hardness and to reduce the thickness of the hard coat layer. The film thickness of the hard coat layer can be determined by observing the cross section of the hard coat layer with a scanning electron microscope (SEM). Specifically, using a scanning electron microscope image, the film thickness of three hard coat layers is measured in one image, and this is performed for five images, and the average value of the measured film thickness is calculated.

  The lower limit of the film thickness of the hard coat layer 12 is more preferably 8 μm or less from the viewpoint of suppressing cracking of the hard coat layer. Further, from the viewpoint of suppressing curling while reducing the thickness of the hard coat layer, the film thickness of the hard coat layer 12 is more preferably 0.5 μm or more and 5.0 μm or less.

  The refractive index of the hard coat layer 12 may be 1.50 or more and 1.60 or less. The lower limit of the refractive index of the hard coat layer 12 may be 1.52 or more, and the upper limit of the refractive index of the hard coat layer 12 may be 1.56 or less. The refractive index difference between the light-transmitting substrate 11 and the hard coat 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 hard coat 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 hard coat 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 transparent). The Becke method (for materials) is used (using a Cargill reagent with a known refractive index, the powder sample is placed on a glass slide, the reagent is dropped on the sample, and the sample is immersed in the reagent. It is possible to use a method in which the refractive index of the reagent is the refractive index of the sample, which is observed by microscopic observation, and the bright line (Becke line) generated in the sample contour due to the difference in refractive index between the sample and the reagent cannot be visually observed. .

  The hard coat layer 12 can be composed of at least a resin. The hard coat layer 12 may contain a leveling agent, particles, and a water contact angle reducing material 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 polymerized product (crosslinked product) and / or a thermally polymerizable compound of an ionizing radiation 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 polymer, which 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 hard coat layer having high hardness, pentaerythritol triacrylate (PETA), dipentaerythritol hexaacrylate (DPHA), pentaerythritol tetraacrylate (PETTA), dipentaerythritol pentaacrylate (DPPA) and the like are preferable. .

(Photopolymerizable 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.

(Photopolymerizable prepolymer)
The weight average molecular weight of the photopolymerizable prepolymer is preferably from 10,000 to 80,000, and more preferably from 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, film defects on the coating surface of the coating liquid can be effectively prevented when forming the hard coat 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 hard coat 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-type leveling agent is preferable from a viewpoint of leveling property. Examples of the fluorine-based leveling agent include F477 and F568 manufactured by DIC, and Footage 212M manufactured by Neos.

  It is preferable that content of a leveling agent is 0.01 to 5 mass parts with respect to 100 mass parts of polymeric compounds in the composition for hard-coat layers mentioned later. By setting the content of the leveling agent within this range, the flatness of the surface of the hard coat 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.

<Water contact angle reducing material>
The water contact angle reducing material is a material for reducing the contact angle with water on the surface of the hard coat layer. The water contact angle reducing material is not particularly limited as long as it has hydrophilicity, but examples of the water contact angle reducing 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 water contact angle reducing materials, an antistatic agent is preferable from the viewpoint of easy precipitation on the surface of the water contact angle reducing material.

(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.

  In order to form the hard coat layer 12 on at least one side of the light transmissive substrate 11, for example, first, a hard coat layer composition containing at least a polymerizable compound is formed on one side of the light transmissive substrate 11. Apply. Subsequently, in order to dry the film-form composition for hard-coat layers, it conveys to the heated zone, the composition for hard-coat layers is dried by various well-known methods, and a solvent is evaporated. Thereafter, the hard coat layer composition is cured by irradiating the coating-form hard coat layer composition with light such as ultraviolet rays or applying heat to polymerize (crosslink) the polymerizable compound. A hard coat layer 12 is formed.

  Examples of the method for applying the hard coat layer composition include known coating methods such as spin coating, dipping, spraying, slide coating, bar coating, roll coating, gravure coating, and die coating.

  When ultraviolet rays are used as the light for curing the hard coat layer composition, ultraviolet rays emitted from an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, a metal halide lamp, or the like 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 hard-coat layers as needed. Further, the hard coat layer composition includes conventionally known dispersants, surfactants, silane cups depending on purposes such as increasing the hardness of the hard coat layer, suppressing cure shrinkage, or controlling the refractive index. Ring agent, thickener, anti-coloring agent, coloring agent (pigment, dye), antifoaming agent, leveling agent, flame retardant, UV absorber, adhesion promoter, polymerization inhibitor, antioxidant, surface modifier, An easy lubricant or the like 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 ionizing radiation polymerizable compound is a compound having an ethylenically unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, etc. may be used alone or in combination. preferable.

  The content of the polymerization initiator in the hard coat layer composition 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 preparing the optical layered body, as shown in FIG. 1B, the protective film 13 is detachably attached to the surface 12 </ b> A of the hard coat layer 12. 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 peeled from the surface 12 </ b> A of the hard coat layer 12 by the adhesive layer 16. Can be pasted as possible. By sticking the protective film 13 to the surface 12A of the hard coat layer 12, it is possible to suppress water remaining when the optical laminate is subjected to saponification treatment, and to prevent the hard coat layer 12 from being contaminated. it can.

<< 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 thereof include a polypropylene film, a polymethylpentene film, a polyvinyl chloride film, a polyvinyl acetal film, a polyether ketone film, a polymethyl methacrylate film, a polycarbonate film, and a polyurethane film. 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 includes a water contact angle increasing material that increases the contact angle of the surface 12A of the hard coat layer 12 with water by peeling off the protective film. When the adhesive layer 16 includes a water contact angle increasing material that increases the contact angle of water on the surface 12A of the hard coat layer 12 with the water, the water contact angle increasing material is removed from the surface of the hard coat layer 12 when the protective film 13 is peeled off. 12A, or the antistatic agent present on the surface of the hard coat layer moves to the adhesive layer side, whereby the contact angle of the surface 12A of the hard coat layer 12 with water can be increased.

<Water contact angle increasing material>
A water contact angle increasing material is a material which makes the contact angle with respect to the water of the surface of a hard-coat layer after peeling of a protective film larger than the contact angle with respect to the water of the surface of a hard-coat layer before sticking a protective film. In this specification, if the contact angle with respect to water on the surface of the hard coat layer after peeling of the protective film is larger than the contact angle with respect to water on the surface of the hard coat layer before applying the protective film, the adhesive layer of the protective film Is determined to contain a water contact angle increasing material.

  The water contact angle increasing material may be an additive having no adhesiveness added to the adhesive layer 16 and / or an adhesive constituting the adhesive layer 16. Such additives are not particularly limited, but for example, one or more materials selected from the group consisting of silicone materials, fluorine materials, and fluorine silicone materials are preferable. Examples of the silicone material include a silicone leveling agent, and examples of the fluorine material include a fluorine surfactant.

  The adhesive layer 16 may be composed of only an adhesive that functions as a water contact angle increasing material, or a water contact angle increasing material and an adhesive that does not function as a water contact angle increasing material. When the water contact angle increasing material is a pressure-sensitive adhesive, the pressure-sensitive adhesive is not particularly limited as long as it has a function of increasing the contact angle with water on the surface 12A of the hard coat layer 12.

  Examples of the adhesive include acrylic adhesive, silicone adhesive, polyester adhesive, polyurethane adhesive, polyamide adhesive, polyvinyl ether adhesive, vinyl acetate / vinyl chloride adhesive, and modified polyolefin adhesive. Adhesives, epoxy adhesives, fluorine adhesives, rubber adhesives, and mixtures thereof can be mentioned. Among these, although having an appropriate adhesive force that functions as a protective film, the peel strength is relatively small, the peeling from the hard coat layer is easy, in the case of moving to the surface of the hard coat layer, Even if it is used as a bonding application, the refractive index is not noticeable because it is not significantly different from the refractive index of the light-transmitting adhesive layer and hard coat layer, and there are many options for the light-transmitting substrate of the protective film, and transparency From the viewpoint that a polyethylene terephthalate substrate with a certain thickness can be used, an acrylic adhesive is 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.

(Rubber adhesive)
Examples of the rubber-based adhesive include natural rubber, polyisoprene rubber, polyisobutylene rubber, polybutadiene rubber, styrene-butadiene-styrene block copolymer, and styrene-isoprene-styrene block copolymer as main components.

  After the protective film 13 is attached to the hard coat layer 12, the protective film 13 is peeled from the hard coat layer 12 as shown in FIG. Thereby, the contact angle with respect to the water of the surface 12A of the hard-coat layer 12 becomes larger than the contact angle with respect to the water of the surface 12A of the hard-coat layer 12 before sticking of the protective film 13, and the optical shown by FIG. 2 (B). The laminated body 10 can be obtained.

  From the viewpoint of the antifouling property of the hard coat layer, the contact angle of the surface 12A of the hard coat layer 12 to the water after the protective film 13 is peeled is the contact angle of the surface 12A of the hard coat layer 12 to the water before the protective film 13 is attached. It is preferably 5 ° or more larger than the angle, and more preferably 7 ° larger. The contact angle with water on the surface of the hard coat 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 is dropped on the surface of the hard coat layer, and then the contact angle after 10 seconds is set at 1 second intervals. Ten points are measured 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 of the surface 12A of the hard coat layer 12 after the protective film 13 is peeled is 65 ° or more. When the contact angle is 65 ° or more, even a hard coat layer for bonding use can be used for a clear hard coat layer.

  The contact angle with respect to water on the surface 12A of the hard coat layer 12 before the protective film 13 is attached is preferably less than 65 °, and preferably 60 ° or less. The contact angle to water on the surface 12A of the hard coat layer 12 after the protective film 13 is peeled off can be applied to bonding applications if the processing conditions in the post-process are devised, and also suitable for antifouling in clear hard coat layer applications. It is preferable that it is 95 degrees or less from a viewpoint of exhibiting property. It is preferable that the contact angle with respect to water on the surface 12A of the hard coat layer 12 after the protective film 13 is peeled is 80 ° or less from the viewpoint of easy processing in bonding applications.

  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.

  In the present embodiment, since the adhesive layer 16 contains a water contact angle increasing material that increases the contact angle of the surface 12A of the hard coat layer 12 with water, the protective film 13 is peeled off from the surface 12A of the hard coat layer 12. When the protective film 13 is peeled off from the surface 12A of the hard coat layer 12 and then the contact angle with respect to the water of the surface 12A of the hard coat layer 12 after the protective film 13 is peeled off before the protective film 13 is attached. The contact angle with respect to water of the surface 12A of the hard coat layer 12 can be larger than the contact angle with water of the surface 12A of the hard coat layer 12 after the protective film 13 is peeled off. The reason for this is not clear, but when the protective film is peeled from the hard coat layer, the water contact in the adhesive layer of the protective film can be achieved even when the water contact angle increasing material is an adhesive or not. Since a part of the angle increasing material moves to the surface of the hard coat layer, it is considered that the contact angle with water on the surface of the hard coat layer after the protective film 13 is peeled is increased. When the water contact angle increasing material contained in the adhesive layer is an adhesive and the hard coat layer contains a water contact angle reducing material, when the protective film is peeled off, a part of the adhesive is Water on the surface 12A of the hard coat layer 12 after peeling off the protective film 13 so that the pressure-sensitive adhesive remaining on the adhesive layer sticks and peels off the water contact angle reducing material present on the surface of the hard coat layer. It is thought that the contact angle with respect to increases. In general, since the protective film is for protecting the surface of the hard coat layer, it is not preferable that the components of the adhesive layer adhere to the surface of the hard coat layer when the protective film is peeled off. It is technical common sense. Therefore, it can be said that the effect of the present invention that the contact angle with respect to water on the surface of the hard coat layer is increased by unexpectedly adhering the components of the adhesive layer to the surface of the hard coat layer is an unexpected effect.

  Conventionally, a protective film may be attached to the surface of the hard coat layer before the saponification treatment. In this embodiment, the protective film 13 is used to protect the water on the surface 12A of the hard coat layer 12 against water. Since the contact angle is controlled, no special member or the like is required, and the contact angle with respect to water on the surface 12A of the hard coat layer 12 can be controlled by a simple method.

  Since the optical laminated body 10 in this embodiment can be applied to both a bonding use and a clear hard coat layer use, it is excellent in productivity.

  In the optical laminated body 10 of this embodiment, since a contact angle can be controlled by the protective film 13, even if it is the same hard-coat layer, it can be changed into a desired contact angle for every use. Thereby, cost reduction can be aimed at.

  Such an optical laminate 10 can be used by being incorporated into, for example, an image display device with a touch panel or an image display device that does not include a touch panel. 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 hard coat layer 12 is disposed on the viewer side with respect to the light transmissive substrate 11. The surface on the observer side of the optical laminate 10 (the surface 12A of the hard coat layer 12) is in contact with the light-transmitting 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 curable resin precursor.

  When the display panel 30 and the touch panel 50 are fixed by the light-transmitting adhesive layer 60, first, a liquid curable adhesive layer composition is applied to the surface 12A of the hard coat layer 12 to provide curable adhesion. A coating film of the layer composition 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 FIG. 3, the light-transmitting adhesive layer 60 and the touch panel 30 are disposed on the viewer side of the optical laminate 10, but the water 12 on the surface 12 of the hard coat layer 12 after the protective film 13 is peeled off. Since the contact angle is 65 ° or more, the optical laminate 10 can be incorporated into an image display device in which the light-transmitting adhesive layer 60 and the touch panel 30 are not disposed. In this case, the hard coat layer 12 functions as a clear hard coat layer.

  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 “Futterent 212M”, manufactured by Neos): 0.5 parts by mass (converted to 100% solid content)
Mixture of methyl isobutyl ketone (MIBK) and methyl ethyl ketone (MEK) (MIBK / MEK = 50/50): 156.8 parts by mass

<Adhesive layer composition>
Each component was blended so as to have the composition shown below to obtain an adhesive layer composition and the like.
(Composition 1 for adhesive layer)
・ Acrylic acid ester copolymer resin (Product name “Arontack SCL-200”, manufactured by Toa Gosei Chemical Co., Ltd., solid content 40%): 10 parts by mass ・ Silicone leveling agent (Product name “10-28”, Dainichi Chemical Industries) 0.15 parts by mass, toluene: 10 parts by mass, ethyl acetate: 10 parts by mass

(Adhesive layer composition 2)
・ Acrylic acid ester copolymer resin (Product name “Alontack SCL-200”, manufactured by Toa Gosei Chemical Co., Ltd., solid content 40%): 10 parts by mass ・ Fluorosurfactant (Product name “Factent 601ADH2”, manufactured by Neos Co., Ltd. ): 0.15 parts by mass, toluene: 10 parts by mass, ethyl acetate: 10 parts by mass

(Adhesive layer composition 3)
・ Acrylic acid ester copolymer resin (Product name “Arontack SCL-200”, manufactured by Toa Gosei Chemical Co., Ltd., solid content 40%): 10 parts by mass ・ Fluorosilicone material (Product name “KP-911”, manufactured by Shin-Etsu Silicone Co., Ltd. ): 0.15 parts by mass, toluene: 10 parts by mass, ethyl acetate: 10 parts by mass

(Adhesive layer composition 4)
As the adhesive layer composition 4, a solvent-type rubber-based adhesive (product name “Olivein BPS3757-1”, manufactured by Toyo Ink Co., Ltd.) was used.

(Adhesive layer composition 5)
-Acrylic ester copolymer resin (Product name "Aron Tack SCL-200", manufactured by Toa Gosei Chemical Co., Ltd., solid content 40%): 10 parts by mass-Toluene: 10 parts by mass-Ethyl acetate: 10 parts by mass

(Adhesive layer composition 6)
As the adhesive layer composition 6, a urethane-based adhesive (product name “Olivein SH-101”, manufactured by Toyo Ink Co., Ltd.) was used.

<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, and irradiating the ultraviolet light with a cumulative light quantity of 100 mJ / cm ² under a nitrogen atmosphere (oxygen concentration of 200 ppm or less) to cure the coating film, A hard coat layer having a thickness of 5 μm (when cured) was formed.

  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 to form a 20 μm thick adhesive layer. A protective film was formed.

  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 prepared 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 1>
In Comparative Example 1, an optical laminate was produced in the same manner as in Example 1 except that the adhesive layer composition 6 was used instead of the adhesive 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 attaching the protective film and the optical laminate after peeling off the protective film. 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.
○: Defects such as change in haze value and appearance stain were not confirmed, or some change such as change in haze value and appearance stain was confirmed, but it was at a level having no practical problem.
X: Defects such as changes in haze value and appearance contamination were clearly confirmed.

<Anti-fouling evaluation>
In the optical laminates obtained in Examples and Comparative Examples, the antifouling property of the surface of the hard coat layer after the protective film was peeled was evaluated. In the antifouling evaluation, 10 test subjects had their thumb fingerprints in close contact with the surface of the hard coat layer for 10 seconds, and then wiped with a wiper (product name “ASPURE Proprea II, manufactured by ASONE”). The evaluation criteria were as follows: each self-fingerprint was checked to see if it was wiped off.
A: Seven or more subjects evaluated that the fingerprints were wiped off.
X: Six or less subjects evaluated that the fingerprint was wiped off.

The results are shown in Table 1.

  In the optical laminated body according to Comparative Example 1, the contact angle with respect to water was larger after the protective film was peeled than before the protective film was peeled, but the contact angle was not 65 ° or more. On the other hand, in the optical laminates according to Examples 1 to 5, the contact angle with respect to water is larger after the protective film is peeled than before the protective film is peeled, and the contact angle is 65 ° or more. It was.

  In the optical laminates according to Examples 1 to 5, no change in haze value, defects such as appearance stains and flatness reduction were confirmed, or there was a slight change in haze value, defects such as appearance stains and flatness reduction. Although confirmed, it was at a level with no problem in practical use, so that the contact angle with water could be increased without affecting the transparency.

  In the optical laminated body with a protective film used in Example 4, Example 5 and Comparative Example 1, the peelability when the protective film was peeled was examined. The protective film used in Example 4 and Example 5 were examined. The protective film used in Example 2 had an appropriate adhesive force that functioned as a protective film, and the optical laminate with the protective film used in Example 5 had the protective film used in Example 4. The protective film could be peeled more easily than the optical laminate. Therefore, it was confirmed that the protective film can be peeled from the hard coat layer more easily by using the acrylic pressure-sensitive adhesive as the pressure-sensitive adhesive than by the rubber-based pressure-sensitive adhesive. In addition, in the optical laminated body with a protective film used by the comparative example 1, since the urethane type adhesive was used as an adhesive, adhesive force was weak and it peeled easily from the hard-coat layer.

DESCRIPTION OF SYMBOLS 10 ... Optical laminated body 11 ... Light-transmitting base material 12 ... Hard-coat 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 (6)

An optical laminate water contact angle control method for controlling a contact angle of water with an optical laminate comprising a light transmissive substrate and a hard coat layer provided on at least one side of the light transmissive substrate. ,
The surface of the hard coat layer formed on at least one side of the light transmissive substrate is provided with a base film, and a contact angle with respect to water of the surface of the hard coat layer provided on one surface of the base film. A step of attaching a protective film comprising a pressure-sensitive adhesive layer containing a water contact angle increasing material to be increased by the pressure-sensitive adhesive layer; and
The protective film is peeled from the hard coat layer, and the contact angle with respect to water on the surface of the hard coat layer after peeling of the protective film is determined to be the contact with water on the surface of the hard coat layer before application of the protective film. A method for controlling the water contact angle of an optical laminate, the method comprising a step of setting the contact angle to water on the surface of the hard coat layer after peeling of the protective film to be 65 ° or more.   The contact angle with respect to the water of the surface of the said hard-coat layer after peeling of the said protective film is 5 degrees or more larger than the contact angle with respect to the water of the surface of the said hard-coat layer before sticking of the said protective film. A method for controlling a water contact angle of an optical laminate.   The method for controlling the water contact angle of an optical laminate according to claim 1, wherein the water contact angle increasing material is one or more materials selected from the group consisting of silicone materials, fluorine materials, and fluorine silicone materials. . 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 hard coat layer provided on at least one side of the light transmissive substrate,
The protective film is provided on one surface of the base film and the base film, and includes a water contact angle increasing material for increasing a contact angle with respect to water on the surface of the hard coat layer, and the hard coat layer With an adhesive layer attached to the surface,
When the protective film is peeled from the optical laminate, the water contact angle on the surface of the hard coat layer after peeling of the protective film is the water on the surface of the hard coat layer before the protective film is attached. The optical laminated body with a protective film which is larger than the contact angle with respect to water, and the contact angle with respect to the water of the surface of the said hard-coat layer after peeling of the said protective film becomes 65 degrees or more.   The contact angle with respect to the water of the surface of the said hard-coat layer after peeling of the said protective film is 5 degrees or more larger than the contact angle with respect to the water of the surface of the said hard-coat layer before sticking of the said protective film. Optical laminate with protective film.   The optical laminated body with a protective film according to claim 4, wherein the water contact angle increasing material is one or more materials selected from the group consisting of a silicone-based adhesive, a fluorine-based adhesive, and a fluorine-silicone-based adhesive. .

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