JP5712742B2 - Optical laminate - Google Patents

Description

The present invention relates to an optical laminate.

A front panel of a display panel such as a liquid crystal display (LCD) is provided with a panel base material such as a touch panel which is an input means for the display panel, and a film base material for protecting or decorating the display panel. This has been done conventionally. As such a base material, an optical laminate comprising a light-transmitting base material and a hard coat layer is known (see, for example, Patent Documents 1 and 2).

However, the optical laminated body has a problem that the hard coat layer is made of a plastic material such as an acrylic resin and the optical laminated bodies are easily adhered to each other. Therefore, when the sheet | seat of the optical laminated body was wound up with the roll at the time of a manufacturing process, there existed a problem that sheets adhered and a sheet | seat was torn.
In addition, the optical layered body also has a problem that, for example, heat shrinkage occurs when the coating film is cured by ultraviolet irradiation when the hard coat layer is formed, and deformation such as curling occurs.

Further, when such an optical laminate is used as a decorative panel, there has been a problem that the ink coating property is poor when screen printing or the like is performed on the optical laminate.

JP 2003-320609 A JP 2005-71901 A

An object of the present invention is to provide an optical layered body that prevents sticking to each other and is excellent in coatability during post-processing printing.

The present invention comprises a light transmissive substrate, a hard coat layer (A) on one surface of the light transmissive substrate, and a hard coat layer (B) on the other surface of the light transmissive substrate. The hard coat layer (A) is a layer formed using a hard coat layer (A) composition containing a leveling agent having a reactive functional group and a binder resin. The hard coat layer (B) is a layer formed using a composition for a hard coat layer (B) containing a leveling agent having no reactive functional group, a lubricant and a binder resin. It is an optical laminated body.
The binder resin of the composition for hard coat layer (A) and the composition for hard coat layer (B) is composed of pentaerythritol tri (meth) acrylate, polymethyl (meth) acrylate, and isocyanuric acid ethylene oxide-modified di and triacrylate. It is preferable to contain at least one selected from the group consisting of
The lubricant is preferably at least one fine particle selected from the group consisting of silica, silicone, high-density polyethylene, polystyrene, and polystyrene acrylic.
The easy lubricant preferably has an average particle size of 100 to 800 nm.
The present invention is described in detail below.

This invention is an optical laminated body characterized by having a hard-coat layer which consists of a specific component on both surfaces of a light-transmitting base material and the said light-transmitting base material, respectively. For this reason, the optical laminated body of this invention can prevent sticking mutually, and is excellent also in the coating property at the time of post-processing printing.

The optical layered body of the present invention has a hard coat layer formed on both surfaces of a light-transmitting substrate using a hard coat layer composition containing a leveling agent and a binder resin. One hard coat layer is a layer formed using a lubricant. For this reason, the optical laminated body of this invention can prevent mutually sticking, when winding up in roll shape.
In the optical layered body of the present invention, one hard coat layer is a layer (hard coat layer (A)) formed using a leveling agent having a reactive functional group.
Furthermore, in the optical layered body of the present invention, the other hard coat layer is a layer (hard coat layer (B)) formed using a leveling agent having no reactive functional group. For this reason, when using such a hard-coat layer (B) as a back surface of a decorative film about the optical laminated body of this invention, it becomes the thing excellent also in the coating property at the time of post-process printing.

The optical layered body of the present invention has a light transmissive substrate.
The light-transmitting substrate preferably has transparency, smoothness, heat resistance, and excellent mechanical strength. Specific examples of the material for forming the light-transmitting substrate include polyester (polyethylene terephthalate, polyethylene naphthalate), triacetyl cellulose (TAC), cellulose diacetate, cellulose acetate butyrate, polyester, polyamide, polyimide, and polyether. Examples thereof include thermoplastic resins such as sulfone, polysulfone, polypropylene, polymethylpentene, polyvinyl chloride, polyvinyl acetal, polyether ketone, polymethyl methacrylate, polycarbonate, and polyurethane. Preferably, in terms of high heat resistance, Examples include polyester (polyethylene terephthalate, polyethylene naphthalate).

As the light transmissive substrate, an amorphous olefin polymer (Cyclo-Olefin-Polymer: COP) film having an alicyclic structure can also be used. This is a base material in which a norbornene polymer, a monocyclic olefin polymer, a cyclic conjugated diene polymer, a vinyl alicyclic hydrocarbon polymer resin, or the like is used. ZEONEX and ZEONOR (norbornene resin) manufactured by Sumitomo Bakelite Co., Ltd., Sumilite FS-1700, JSR arton (modified norbornene resin), Mitsui Chemicals Appel (cyclic olefin copolymer), Ticona Topas ( Cyclic olefin copolymer), Hitachi Chemical's Optretz OZ-1000 series (alicyclic acrylic resin), and the like. Further, the FV series (low birefringence, low photoelastic modulus film) manufactured by Asahi Kasei Chemicals is also preferable as an alternative base material for triacetylcellulose.

The light-transmitting substrate preferably uses the thermoplastic resin as a flexible film-like body, but uses a plate of these thermoplastic resins depending on the use mode in which curability is required. It is also possible, or a glass plate plate may be used.

The thickness of the light transmissive substrate is preferably 20 to 300 μm, more preferably the lower limit is 30 μm and the upper limit is 200 μm. When the light-transmitting substrate is a plate-like body, the thickness may exceed these thicknesses.
The above light-transmitting substrate is called an anchor agent or primer in addition to physical treatment such as corona discharge treatment and oxidation treatment in order to improve adhesion when forming a hard coat layer on the surface. Application of the paint may be performed in advance.

The optical layered body of the present invention has a hard coat layer (A) on one surface of the light transmissive substrate and a hard coat layer (B) on the other surface of the light transmissive substrate.
The hard coat layer (A) is formed using a composition for a hard coat layer (A) containing a leveling agent having a reactive functional group and a binder resin.

Here, generally, the leveling agent can be oriented on the surface of the coating film in the drying process, uniformizing the surface tension of the coating film, preventing floating mottle and repellency, and improving wetness to the object to be coated. .
In the present invention, the hard coat layer (A) contains a leveling agent having a reactive functional group. By containing such a leveling agent, when the optical laminate having the hard coat layer (A) is wound up with a roll, set-off can be prevented. Moreover, antifouling performance can be maintained for a long time.

Examples of the leveling agent having a reactive functional group include a fluorine leveling agent having an acrylate functional group, a silicon leveling agent, and an acrylic leveling agent.
Among these, a fluorine-based leveling agent having an acrylate-based functional group and a silicon-based leveling agent are preferable from the viewpoint that they can easily wipe off dirt such as fingerprints and oil-based inks.

Commercially available leveling agents having the above-mentioned reactive functional groups include Daikin Industries, Ltd. OPTOOL DAC, DIC's MegaFac RS series (RS71, RS101, RS102, RS201, RS401, and RS701), DIC's defens Fluorine leveling agents having reactive functional groups such as SER3000 (TF3000, TF3001, TF3002, TF3025 and TF3026); reactions such as X22-163A manufactured by Shin-Etsu Chemical Co., Ltd. Examples thereof include a silicon-based leveling agent having a functional group.
Can be mentioned. Among them, RS71 manufactured by DIC is preferable in terms of repelling dirt and good wiping properties.

It is preferable that content in the said composition for hard-coat layers (A) of the leveling agent which has the said reactive functional group is 0.05-5 mass parts with respect to 100 mass parts of binder resin solid content. If it is less than 0.05 parts by mass, a smooth film surface cannot be obtained, and the expected slipperiness and antifouling performance may not be obtained. If the amount exceeds 5 parts by mass, the composition may foam or the surface hardness may be lowered or phase-separated in the formed coating film.

As the binder resin contained in the hard coat layer (A) composition, a transparent resin is preferable. For example, an ionizing radiation curable resin, an ionizing radiation curable resin, which is a resin curable by ultraviolet rays or an electron beam, and Mention a mixture with a solvent-drying resin (such as a thermoplastic resin, or a resin that forms a film by simply drying the solvent added to adjust the solid content during coating), or a thermosetting resin. it can. More preferred is an ionizing radiation curable resin. In the present specification, “resin” is a concept including resin components such as monomers and oligomers.

Examples of the ionizing radiation curable resin include compounds having one or more unsaturated bonds such as compounds having an acrylate functional group. Examples of the compound having one unsaturated bond include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone and the like. Examples of the compound having two or more unsaturated bonds include polymethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri ( Polyfunctional compounds such as (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentylglycol di (meth) acrylate, and these polyfunctional compounds and (meth) A reaction product with an acrylate or the like (for example, a poly (meth) acrylate ester of a polyhydric alcohol) can be used. In the present specification, “(meth) acrylate” refers to methacrylate and acrylate.
In addition, these compounds may be those in which a part of the molecular skeleton is modified, such as those modified with ethylene oxide, propylene oxide, caprolactone, isocyanuric acid, alkyl, cyclic alkyl, aromatic, bisphenol, etc. Can be used.

In addition to the above compounds, relatively low molecular weight polyester resins having unsaturated double bonds, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, etc. It can be used as an ionizing radiation curable resin.

The ionizing radiation curable resin can be used in combination with a solvent-drying resin. By using the solvent-drying resin in combination, it is possible to effectively prevent coating defects on the coated surface, thereby obtaining a more excellent glossy blackness.
The solvent-drying resin that can be used in combination with the ionizing radiation curable resin is not particularly limited, and a thermoplastic resin can be generally used.

The thermoplastic resin is not particularly limited. For example, a styrene resin, a (meth) acrylic resin, a vinyl acetate resin, a vinyl ether resin, a halogen-containing resin, an alicyclic olefin resin, a polycarbonate resin, or a polyester resin. Examples thereof include resins, polyamide-based resins, cellulose derivatives, silicone-based resins, rubbers, and 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, styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters, etc.) are preferable from the viewpoint of excellent film forming properties, transparency and weather resistance. .

Examples of the thermosetting resin include phenol resin, urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine-urea cocondensation resin, silicon resin, poly resin Examples thereof include siloxane resins.

The binder resin component of the hard coat layer (A) preferably contains an acrylic monomer or oligomer having a weight average molecular weight of 1000 or less and an acrylic polymer having a weight average molecular weight of 10,000 to 40,000.
The said weight average molecular weight is a polystyrene conversion value by the gel permeation chromatography (GPC) method in a THF solvent, and when there is no molecular weight distribution, it means the molecular weight of the compound itself.

Further, the binder resin is a group consisting of pentaerythritol tri (meth) acrylate, isocyanuric acid ethylene oxide-modified di- and tri (meth) acrylate, and polymethyl (meth) acrylate in that the pen slidability can be improved. It is preferable to contain at least one selected from more.
The pen slidability means a mechanical strength that does not damage the optical laminate when it is repeatedly pressed by a contact body such as a fingertip or a stylus (pen tip).
As said binder resin, it is more preferable to contain 3 types, pentaerythritol tri (meth) acrylate, isocyanuric acid ethylene oxide modified di and tri (meth) acrylate, and polymethyl (meth) acrylate.

The composition for hard coat layer (A) may contain other components as needed in addition to the components described above. Examples of the other components include reactive fine particles, a photopolymerization initiator, an antistatic agent, an antiglare agent, a crosslinking agent, a curing agent, a polymerization accelerator, a viscosity modifier, and an anti-fingerprint agent.
In addition, it is preferable that the composition for hard-coat layers (A) does not contain the lubricant mentioned later. If the lubricant is contained, pen slidability or pencil hardness may be lowered.

The hard coat layer (A) composition is a leveling agent having the reactive functional group described above,
It can be prepared by mixing and dispersing the binder resin and any other components with a solvent.
Examples of the solvent include water, alcohol (eg, methanol, ethanol, propanol, isopropanol, n-butanol, s-butanol, t-butanol, benzyl alcohol, PGME), ketone (eg, acetone, methyl ethyl ketone, methyl isobutyl ketone). , Cyclohexanone, heptanone, diisobutyl ketone, diethyl ketone), esters (eg, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl formate, ethyl formate, propyl formate, butyl formate, PGMEA), aliphatic hydrocarbons (eg, Hexane, cyclohexane), halogenated hydrocarbons (eg, methylene chloride, chloroform, carbon tetrachloride), aromatic hydrocarbons (eg, benzene, toluene, xylene), amides (eg, dimethylformamide, dimethylacetate) De, n- methylpyrrolidone), ethers (e.g., diethyl ether, dioxane, tetrahydrofuran), ether alcohols (examples include 1-methoxy-2-propanol) and the like. These may be used alone or in combination of two or more.
The method for mixing and dispersing is not particularly limited, and for example, a known method such as a paint shaker or a bead mill can be used.

The hard coat layer (A) is formed using the hard coat layer (A) composition.
That is, the hard coat layer (A) composition is applied to one side of the light-transmitting substrate to form a coating film, dried as necessary, and then hardened by curing the coating film. A layer (A) can be formed.
Examples of the method for applying the hard coat layer (A) composition include application methods such as a roll coating method, a Miya bar coating method, and a gravure coating method.
Although the said drying is not specifically limited, It is preferable to carry out for 20 second-5 minutes at 40-100 degreeC.
The method for curing the coating film is not particularly limited, and any known method may be used. Examples thereof include a method for curing the coating film by irradiating it with ultraviolet rays.

The layer thickness of the hard coat layer (A) is preferably 3 to 20 μm. If it is less than 3 μm, not only coating spots and interference unevenness appear and the appearance deteriorates, but there is a possibility that the hardness may not be sufficient. If it exceeds 20 μm, the optical laminate itself may be cracked and wound, and it may be expensive. In addition, the optical characteristics may be deteriorated.
The layer thickness is more preferably 4 to 8 μm.
The layer thickness is a value obtained by observing and measuring a cross section with an electron microscope (SEM, TEM, STEM).

The optical layered body of the present invention further has a hard coat layer (B) on a surface different from the surface of the light-transmitting substrate having the hard coat layer (A).
The hard coat layer (B) is a layer formed using a composition for a hard coat layer (B) containing a binder resin, a leveling agent having no reactive functional group, and a lubricant.

It is preferable that the leveling agent which does not have the said reactive functional group is a leveling agent which does not have the reactive functional group which the leveling agent used in the composition for hard-coat layers (A) mentioned above has.
When the hard coat layer (B) is used as a back surface of a decorative film by being formed using a composition containing a leveling agent having no reactive functional group. The coating property during post-processing printing can be excellent.
Examples of the leveling agent having no reactive functional group include water-repellent and lipophilic ones, and examples thereof include a fluorine-based leveling agent and an acrylic leveling agent that do not have the reactive functional group described above. .

As a commercial item of the leveling agent which does not have the said reactive functional group, the Megafac series made by DIC (MCF350-5, F444, F445, F470, F482 and F486) etc. can be mentioned, for example.

It is preferable that content in the said composition for hard-coat layers (B) of the leveling agent which does not have the said reactive functional group is 0.05-2 mass parts with respect to 100 mass parts of binder resin solid content. If the amount is less than 0.05 parts by mass, a smooth film surface may not be obtained. If it exceeds 2 parts by mass, the coatability will be insufficient during post-processing printing, the printed layer will not be suitably formed, the composition will foam, and the surface hardness of the resulting coating will decrease. There is a risk of phase separation, phase separation, and settling.

As said binder resin, the thing similar to binder resin which can be used for the hard-coat layer (A) mentioned above can be mentioned.
Among them, the binder resin used in the composition for the hard coat layer (B) is for the hard coat layer (A) in that it can prevent curling of the optical laminate due to thermal shrinkage during post-process manufacturing. It is preferable that it is the resin composition similar to the resin composition of the binder resin of a composition.

The composition for a hard coat layer (B) further contains a lubricant.
By containing the above-mentioned lubricant, when the optical laminate is wound up in a roll shape, the optical laminates can be prevented from sticking to each other.

Examples of the lubricant include particles composed of at least one selected from the group consisting of fine particles of inorganic compounds and fine particles of organic compounds. In addition, the lubricant is preferably at least one fine particle selected from the group consisting of silica, silicone, high-density polyethylene, polystyrene, and polystyrene acrylic.
Furthermore, the lubricant is more preferably silica particles in terms of high heat resistance, low cost, and easy availability.

The easy lubricant preferably has an average particle size of 100 to 800 nm. If it is less than 100 nm, the slipperiness may not be exhibited. If it exceeds 800 nm, the optical properties may be deteriorated.
The average particle diameter of the lubricant is more preferably a lower limit of 100 nm and a more preferable upper limit of 500 nm.
The average particle diameter is a value obtained by measurement by a laser diffraction / scattering method.
Moreover, when providing the optical laminated body of this invention further with the Newton ring generation | occurrence | production prevention effect, it is preferable that the average particle diameter of the said lubricant is 4-25 micrometers.

It is preferable that content in the composition for hard-coat layers (B) is 1-10 mass parts with respect to 100 mass parts of binder resin solid content of the said lubricant.
There exists a possibility that the sticking prevention effect may not express that it is less than 1 mass part. If it exceeds 10 parts by mass, the optical properties may be deteriorated.
As for content of the said lubricant, it is more preferable that it is 3-6 mass parts.

The composition for the hard coat layer (B) may contain other components, similar to the hard coat layer (A) described above.
As said other component, the thing similar to the other component which can be used by the hard-coat layer (A) mentioned above can be mentioned.

The preparation of the hard coat layer (B) composition and the hard coat layer (B) are formed in the same manner as the preparation of the hard coat layer (A) composition and the hard coat layer (A) described above. It can be carried out.

The layer thickness of the hard coat layer (B) is preferably 3 to 20 μm. If it is less than 3 μm, not only coating spots and interference unevenness appear and the appearance deteriorates, but there is a possibility that the hardness may not be sufficient. If it exceeds 20 μm, the optical laminate itself may be cracked and wound, and it may be expensive. In addition, the optical characteristics may be deteriorated.
The layer thickness is more preferably 4 to 8 μm.
The layer thickness of the hard coat layer (B) may be the same as the layer thickness of the hard coat layer (A) in that curling due to thermal shrinkage during processing in the optical laminate can be prevented. Further preferred.
The layer thickness is a value obtained by observing and measuring a cross section with an electron microscope (SEM, TEM, STEM).

As described above, the optical layered body of the present invention has hard coat layers (A) and (B) made of specific components on both surfaces of the light-transmitting substrate. For this reason, it can prevent that optical laminated bodies adhere mutually. In addition, the optical laminate can be prevented from curling due to heat shrinkage.
Furthermore, when the hard coat layer (A) is used as the front surface and the hard coat layer (B) is used as the back surface, that is, when the hard coat layer (A) is placed on the outermost surface, the present invention is applied. This optical laminate is excellent in pen slidability, fingerprint resistance, and coating properties during post-processing printing.

The optical layered body of the present invention may have other layers in addition to the above-described light-transmitting substrate, hard coat layer (A), and hard coat layer (B). Examples of the other layers include an antistatic layer, an antiglare layer, a low refractive index layer, a high refractive index layer, and an antifouling layer. These layers can be formed by a known method using a known material.

The optical layered body of the present invention preferably has a total light transmittance of 90% or more. If it is less than 90%, color reproducibility and visibility may be impaired when the optical laminate of the present invention is mounted on the surface of an image display device. The total light transmittance is more preferably 95% or more, and still more preferably 98% or more.
The total light transmittance can be measured by a method based on JIS K-7361 using a haze meter (manufactured by Murakami Color Research Laboratory, product number: HM-150).

The optical layered body of the present invention preferably has a haze of 1.5% or less. If it exceeds 1.5%, the color reproducibility and visibility may be impaired when mounted on the display surface, and a desired contrast may not be obtained. The haze is more preferably 0.3 to 1.2%.
The haze can be measured by a method based on JIS K-7136 using a haze meter (manufactured by Murakami Color Research Laboratory, product number: HM-150).

The optical layered body of the present invention is preferably 2H or more, more preferably 3H or more, and more preferably 4H or more in a pencil hardness test (load 7.4 N) according to JIS K5600-5-4 (1999). More preferably.

The optical layered body of the present invention preferably has a transmitted hue b ^* of 3 or less. If it exceeds 3, the film has a yellowish colour, which may impair visibility and color reproducibility. The transmitted hue b ^* is more preferably 2 or less.
The transmitted hue b ^* is a value obtained by measurement using a spectrophotometer (manufactured by Shimadzu Corporation, product number UVPC-2450).

The optical layered body of the present invention can be suitably applied as a touch panel substrate, a decorative film, or the like that can be installed on a display panel such as a liquid crystal display (LCD). In particular, the optical laminate of the present invention is set so that the hard coat layer (A) is the front surface, the hard coat layer (B) is the back surface, and the back surface is in contact with the display panel. The thing excellent in the coating property at the time of post-processing printing can be made. Moreover, the optical layered body of the present invention is excellent in pen scratch resistance, fingerprint resistance and antifouling property.

Since the optical layered body of the present invention has the above-described configuration, it does not stick to each other and has excellent coating properties during post-processing printing.
Therefore, the optical layered body of the present invention is suitably used for displays such as cathode ray tube display devices (CRT), liquid crystal displays (LCD), plasma displays (PDP), electroluminescence displays (ELD), and particularly high definition displays. can do.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples.
In the text, “part” or “%” is based on mass unless otherwise specified.

Example 1
On one side of a PET substrate (Toray Lumirror U46, thickness 188 μm), a hard coat layer (A) composition having the following composition was applied and dried in a thermal oven at a temperature of 50 ° C. for 60 seconds, The hard coating layer (A) having a film thickness of 5 μm was formed by evaporating the solvent and curing the coating film by irradiating with ultraviolet rays so that the integrated light amount was 360 mJ / cm ² . Next, a hard coat layer (B) composition having the following composition is applied to the surface of the PET substrate opposite to the surface on which the hard coat layer (A) layer is formed, and heat at a temperature of 50 ° C. Dry in the oven for 60 seconds to evaporate the solvent in the coating, and from the coating side (the side opposite to the hard coat layer (A) layer of the PET substrate), the integrated light intensity is 360 mJ / cm ² The hard coat layer (B) having a film thickness of 5 μm was formed by irradiating the film to cure the coating film to obtain an optical laminate.
<Composition (1) for hard coat layer (A)>
30 parts by mass of pentaerythritol triacrylate (solid content)
Polymethyl acrylate (weight average molecular weight 40000) 5 parts by mass (solid content)
Isocyanuric acid ethylene oxide modified triacrylate (trade name Aronix M315 Toa Gosei Co., Ltd.) 15 parts by mass (solid content)
Leveling agent a (Product name: Megafuck RS71, Fluorine, manufactured by DIC)
0.25 part by mass photopolymerization initiator (product name: Irgacure (Irg) 184, manufactured by Ciba Japan)
1.7 parts by mass of solvent (MIBK) 46 parts by mass <Composition for hard coat layer (B) (1)>
30 parts by mass of pentaerythritol triacrylate (solid content)
Polymethyl acrylate (weight average molecular weight 40000) 5 parts by mass (solid content)
Isocyanuric acid ethylene oxide modified triacrylate (trade name Aronix M315 Toa Gosei Co., Ltd.) 15 parts by mass (solid content)
Leveling agent c (product name: Mega-Fac MCF350-5, solid content 5% by mass, manufactured by DIC Corporation)
1 part by mass lubricant a (silica particles, average particle size 250 nm, product name SIRMIBK15WT% -E65 solid content 15% by mass, manufactured by CIK Nanotech) 20 parts by mass photopolymerization initiator (product name Irgacure (Irg) 184, Ciba・ Made by Japan)
1.7 parts by mass Solvent methyl isobutyl ketone (MIBK) 33.2 parts by mass

(Example 2)
In Example 1, instead of the hard coat layer (B) composition (1), the same composition as in Example 1 was used except that the hard coat layer (B) composition (2) having the following composition was used. A laminate was obtained.
<Hardcoat layer (B) composition (2)>
30 parts by mass of pentaerythritol triacrylate (solid content)
Polymethyl acrylate (weight average molecular weight 40000) 5 parts by mass (solid content)
Isocyanuric acid ethylene oxide modified triacrylate (trade name Aronix M315 Toa Gosei Co., Ltd.) 15 parts by mass (solid content)
Leveling agent c (product name: Mega-Fac MCF350-5, solid content 5% by mass, manufactured by DIC Corporation)
1 part by mass lubricant a (silica particles, average particle size 250 nm, product name SIRMIBK15WT% -E65 solid content 15% by mass, manufactured by CIK Nanotech) 33.3 parts by mass photopolymerization initiator (product name Irgacure (Irg) 184 , Made by Ciba Japan)
1.7 parts by mass Solvent methyl isobutyl ketone (MIBK) 24.7 parts by mass

(Example 3)
In Example 1, instead of the hard coat layer (B) composition (1), the same composition as in Example 1 was used except that the hard coat layer (B) composition (3) having the following composition was used. A laminate was obtained.
<Composition (3) for hard coat layer (B)>
30 parts by mass of pentaerythritol triacrylate (solid content)
Polymethyl acrylate (weight average molecular weight 40000) 5 parts by mass (solid content)
Isocyanuric acid ethylene oxide modified triacrylate (trade name Aronix M315 Toa Gosei Co., Ltd.) 15 parts by mass (solid content)
Leveling agent c (product name: Mega-Fac MCF350-5, solid content 5% by mass, manufactured by DIC Corporation)
1 part by mass lubricant (silica particles, average particle size 250 nm, product name SIRMIBK15WT% -E65 solid content 15% by mass, manufactured by CIK Nanotech) 10 parts by mass photopolymerization initiator (product name Irgacure (Irg) 184, Ciba・ Made by Japan)
1.7 parts by mass Solvent methyl isobutyl ketone (MIBK) 42.6 parts by mass

(Examples 4 and 5)
In Example 1, instead of the easy lubricant a in the composition (1) for the hard coat layer (B), silica particles (average particle size 100 nm, solid content 15% by mass) (Example 4) or silica particles An optical laminate was produced in the same manner as in Example 1 except that (average particle size 800 nm, solid content 15% by mass) (Example 5) was used.

(Example 6)
In Example 1, instead of the leveling agent a in the composition (1) for the hard coat layer (A), a silicon-based leveling agent having a reactive functional group (product name BYKUV3500, manufactured by Big Chemie Japan) was used. Except for the above, an optical laminate was produced in the same manner as in Example 1.

(Example 7)
In Example 1, instead of the leveling agent c in the composition (1) for the hard coat layer (B), an acrylic leveling agent having no reactive functional group (product name BYK350, manufactured by Big Chemie Japan) was used. An optical laminate was prepared in the same manner as in Example 1 except that it was used.

(Example 8)
Example 1 and Example 1 except that silica particles (average particle size 1000 nm, solid content 15% by mass) were used instead of the lubricant a in the composition (1) for the hard coat layer (B). An optical laminate was produced in the same manner.

Example 9
In Example 1, the optical laminated body was produced like Example 1 except having changed the film thickness of the hard-coat layer (B) into 10 micrometers.

(Comparative Example 1)
In Example 1, instead of the hard coat layer (B) composition (1), the same composition as in Example 1 was used except that the hard coat layer (B) composition (4) having the following composition was used. A laminate was obtained.
<Composition (4) for hard coat layer (B)>
30 parts by mass of pentaerythritol triacrylate (solid content)
Polymethyl acrylate (weight average molecular weight 40000) 5 parts by mass (solid content)
Isocyanuric acid ethylene oxide modified triacrylate (trade name Aronix M315 Toa Gosei Co., Ltd.) 15 parts by mass (solid content)
Leveling agent c (product name: Mega-Fac MCF350-5, solid content 5% by mass, manufactured by DIC Corporation)
1 part by mass photopolymerization initiator (product name: Irgacure (Irg) 184, manufactured by Ciba Japan)
1.7 parts by mass Solvent methyl isobutyl ketone (MIBK) 50.8 parts by mass

(Comparative Example 2)
In the composition (1) for the hard coat layer (B) of Example 1, a leveling agent a having a reactive group (product name: Megafac RS71, fluorine-based, manufactured by DIC) was used instead of the leveling agent c. Except for the above, an optical laminate was produced in the same manner as in Example 1.

(Comparative Example 3)
In Example 1, an optical laminate was produced in the same manner as in Example 1 except that the hard coat layer (B) was not formed.

About each obtained optical laminated body, the following item was evaluated. The evaluation results are shown in Table 1.
(Anti-sticking property)
For each optical layered body, the hard coat layer (A) surface and the hard coat layer (B) surface are rubbed face-to-face to confirm the slipperiness, thereby preventing sticking according to the following criteria. evaluated.
◎: Good sliding property and good anti-sticking property ○: Slightly sticking occurred, but slipping when sliding, no problem with sticking property △: Partial sticking occurred, slipping even when sliding Is insufficient and the sticking property is slightly inferior ×: Sticking occurs on the entire surface, and it does not slip

(Print layer coatability)
For each optical laminate, a screen ink (thermosetting type) film is formed on the surface of the hard coat layer (B), and vertically and horizontally at 1 mm intervals on the outermost surface of SiOx according to the cross-cut test method of JIS K5400. After making 100 grids with 11 cuts each, and attaching Nichiban's cello tape (registered trademark) on the grids, they were quickly pulled in a 90 ° direction and peeled off. The coating layer coatability (coating film adhesion) was evaluated based on the above criteria.
○: The number of grids that were not peeled out of 100 grids was 80 to 100. Δ: The number of grids that were not stripped was 100 to 100, and the number of grids that were not stripped was 30 to 79. The number of grids that were not peeled off was 29 or less

(Heat resistant curling)
For each optical laminate, a hard coat film with dimensions of 100 mm square is placed on a flat surface, subjected to a heat resistance test at 150 ° C. for 1 hour, and the average value of the height of lifting from the four corner planes is calculated. Measured as curl height.
In addition, the height of the curl is when the hard coat layer (B) surface (the surface opposite to the hard coat layer (A) surface) is on the lower side and the hard coat layer (A) surface is on the lower side. Measurements were made for each. When the hard coat layer (B) side is down, the curl height toward the hard coat layer (A) side is negative, and when the hard coat layer (A) is down, B) The curl height toward the surface side was set to a positive value. That is, for example, when the curl height to the hard coat (A) side is 3 mm when the hard coat layer (B) side is on the lower side, it is set to -3 mm, and the hard coat layer (A) layer is on the lower side. When the curl height to the hard coat (B) side is 7 mm, it is set to +7 mm.
The heat resistance curl property was evaluated according to the following criteria.
○: 0 mm or more and less than ± 2 mm Δ: ± 2 mm or more and less than ± 5 mm ×: ± 5 mm or more

(Haze)
About the haze of each optical laminated body, it measured by the method based on JISK-7136 using the haze meter (the product number; HM-150 made by Murakami Color Research Laboratory).

From Table 1, the optical laminated body of the Example of this invention was excellent in sticking prevention property and printing layer coating property. On the other hand, the optical laminated body of the comparative example was not satisfactory in all items.

The optical layered body of the present invention can be suitably applied as a base material or a decorative film for a touch panel installed on a display panel such as a liquid crystal display (LCD).

Claims (4)

Optical laminate having a light transmissive substrate, a hard coat layer (A) on one surface of the light transmissive substrate, and a hard coat layer (B) on the other surface of the light transmissive substrate. Body,
The hard coat layer (A) is a layer formed using a composition for a hard coat layer (A) containing a leveling agent having a reactive functional group and a binder resin,
The hard coat layer (B) is a layer formed using a composition for a hard coat layer (B) containing a leveling agent having no reactive functional group, a lubricant and a binder resin. An optical laminate. The binder resin of the composition for hard coat layer (A) and the composition for hard coat layer (B) comprises pentaerythritol tri (meth) acrylate, polymethyl (meth) acrylate, and isocyanuric acid ethylene oxide-modified di- and triacrylate. The optical laminate according to claim 1, comprising at least one selected from the group. The optical laminate according to claim 1 or 2, wherein the lubricant is at least one fine particle selected from the group consisting of silica, silicone, high-density polyethylene, polystyrene, and polystyrene acrylic. The optical laminate according to claim 3 , wherein the lubricant has an average particle diameter of 100 to 800 nm.