JP6217365B2 - OPTICAL LAMINATE, MANUFACTURING METHOD THEREOF, AND POLARIZING PLATE AND IMAGE DISPLAY DEVICE USING THE SAME - Google Patents

Description

  The present invention relates to an optical laminate, a method for producing the same, a polarizing plate using the same, and an image display device.

In image display devices, LCDs, LCDs equipped with touch panels, ELs, electronic papers, etc. have features such as power saving, light weight, and thinness. Therefore, they have rapidly spread in recent years in place of conventional CRT displays. Yes.
Since the optical layered body used on the surface or inside of such an image display device is usually required to impart hardness so as not to be damaged during handling, a hard coat layer or the like is provided on the light-transmitting substrate. In general, it is possible to impart hardness by providing. For example, in an LCD, a polarizing element is disposed on the image display surface side of a liquid crystal cell, and an image is obtained by using a hard coat film in which a hard coat layer is provided on a light-transmitting substrate as a polarizing plate protective film. Generally, the display surface is given hardness.

Conventionally, a film made of a cellulose ester typified by triacetyl cellulose has been used as a light-transmitting substrate of such a hard coat film. This is because cellulose ester is excellent in transparency and optical isotropy, and has almost no retardation in the plane (low retardation value). Because it has little influence on the display quality of the device and has a suitable water permeability, moisture remaining in the polarizer when the polarizing plate using the optical laminate is produced can be dried through the optical laminate. It is based on advantages such as being able to.
However, the cellulose ester film is a disadvantageous material in terms of cost, and has insufficient moisture resistance and heat resistance. The hard coat film based on the cellulose ester film is used as a polarizing plate protective film in a high temperature and high humidity environment. When used in, the polarizing function such as the polarizing function and hue is lowered.
From the problems of such cellulose ester film, a transparent plastic base material mainly composed of acrylic resin, which is excellent in transparency, heat resistance and mechanical strength, and is cheaper and easier to obtain in the market than cellulose ester film. It has been proposed to use
However, the optical laminate in which the hard coat layer is formed on one side or both sides of the base material mainly composed of the acrylic resin has a problem that the adhesion between the acrylic base material and the hard coat layer is inferior. In addition, a difference in refractive index is generated between the acrylic substrate and the hard coat layer, and when a polarizing plate or the like is formed using the optical laminate, there is a problem that interference fringes are generated and the appearance is poor.

To deal with such problems, for example, in Patent Document 1, in addition to physical treatment such as corona discharge treatment and oxidation treatment on a base film, a coating material called an anchor agent or primer is applied, It is disclosed to improve the adhesion between the base film and the hard coat layer by forming a coat layer. Further, for example, Patent Document 2 discloses a method of forming irregularities at the interface between a base film and a hard coat layer.
However, these methods are inferior in productivity because the number of steps necessary for producing a hard coat film is increased and special treatment is required.

JP 2011-81359 A JP-A-8-197670

In addition, the acrylic base material has the ability to swell the base material with all commonly used solvents, compared with the cellulose ester film and polyester film that are often used in the past. There is a problem that the base material itself is cut off during processing because it is strong and easily received, and there is a problem that the technology known for the conventional transparent plastic base material cannot be used as it is for an acrylic base material.
The present invention, under such circumstances, in the optical laminate having the acrylic base material, the primer layer and, if necessary, the hard coat layer in this order, the acrylic base material itself can be processed without cutting, And it aims at providing the method of suppressing generation | occurrence | production of an interference fringe, improving the adhesiveness of an acrylic base material and a primer layer, and manufacturing this optical laminated body efficiently.

  As a result of intensive research in order to solve the above problems, the present inventor has found that in the optical laminate having an acrylic base material, a primer layer and, if necessary, a hard coat layer in this order, a polyalkylene glycol as a primer layer. It has been found that the above problem can be solved by using a cured product of an ionizing radiation curable resin composition containing di (meth) acrylate, a polyfunctional polymer and a monomer. The present invention has been completed based on such findings.

That is, the present invention provides the following inventions.
[1] An optical laminate having an acrylic base material and a primer layer in this order,
The optical layered product, wherein the primer layer is a cured product of an ionizing radiation curable resin composition A containing 50 to 100% by mass (solid content) of polyalkylene glycol di (meth) acrylate.
[2] The optical laminate according to [1], wherein the glass transition point (Tg) of the acrylic substrate is 110 to 150 ° C.
[3] The optical laminate according to [1] or [2], wherein the amount of polyalkylene glycol di (meth) acrylate in the ionizing radiation curable resin composition A is 70 to 100% by mass (solid content).
[4] The optical laminate according to any one of [1] to [3], wherein the polyalkylene glycol di (meth) acrylate has a molecular weight of 180 to 1,000.
[5] The optical laminate according to any one of [1] to [4], wherein the acrylic substrate is a stretched acrylic substrate.
[6] The optical layered body according to any one of [1] to [5], further including a functional layer on the surface of the primer layer opposite to the acrylic substrate side.
[7] The optical layered body according to [6], wherein the functional layer is a hard coat layer and is a cured product of the ionizing radiation curable resin composition B.
[8] The optical laminate according to any one of [1] to [7], wherein the primer layer contains a functional component.
[9] A polarizing plate formed by laminating the optical laminate according to any one of [1] to [8] on at least one surface of a polarizing film.
[10] An image display device comprising the optical laminate according to any one of [1] to [8] and / or the polarizing plate according to [9].
[11] An ionizing radiation curable resin composition A containing 50 to 100% by mass of polyalkylene glycol di (meth) acrylate in solid content is applied onto an acrylic substrate, dried and cured to form a primer layer. It forms, The manufacturing method of the optical laminated body in any one of [1]-[8] characterized by the above-mentioned.
[12] The ionizing radiation curable resin composition A contains at least one selected from methyl isobutyl ketone, 1-butanol, propylene glycol monomethyl ether and isopropanol as a solvent, and has a drying temperature of 40 to 90. The method for producing an optical laminated body according to [11], which is at ° C.
[13] The functional layer is formed according to [11] or [12], wherein an ionizing radiation curable resin composition B is further applied to the surface of the primer layer opposite to the acrylic substrate side, dried and cured to form a functional layer. A method for producing an optical laminate.

  The optical layered body of the present invention has an acrylic base material, a primer layer and, if necessary, a hard coat layer in this order, the generation of interference fringes is suppressed, and the adhesiveness between the acrylic base material and the primer layer is excellent. Moreover, the manufacturing method of the optical laminated body of this invention can manufacture the said optical laminated body efficiently.

It is a scanning transmission electron micrograph (STEM) which shows the cross section of the one aspect | mode of the optical laminated body of this invention. It is a scanning transmission electron micrograph (STEM) which shows the cross section of the one aspect | mode of the optical laminated body of this invention. 2 is a scanning transmission electron micrograph (STEM) showing a cross section of the optical layered body of the present invention obtained in Example 10. FIG. In the cross section of the optical laminated body of this invention obtained in Example 10, it is a scanning transmission electron micrograph (STEM) which expands and shows from a hard-coat layer-primer layer interface to an acrylic base material-primer layer interface. 10 is a scanning transmission electron micrograph (STEM) showing a cross section of the optical layered body obtained in Comparative Example 8. FIG. In the cross section of the optical laminated body of this invention obtained by the comparative example 8, it is a scanning transmission electron micrograph (STEM) which expands and shows from a hard-coat layer-primer layer interface to an acrylic base material-primer layer interface.

The optical layered body according to the present invention is an optical layered body having an acrylic base material, a primer layer and, if necessary, a hard coat layer in this order, and the primer layer contains 50 polyalkylene glycol di (meth) acrylate. It is a cured product of ionizing radiation curable resin composition A containing ˜100% by mass.
The optical layered body of the present invention is obtained by laminating the cured product of the ionizing radiation curable resin composition A on an acrylic base material, and as shown in FIGS. 1 and 2, the interface between the acrylic base material and the primer layer. (Hereinafter, it may be abbreviated as “acrylic substrate-primer layer interface”) has irregularities.

  The optical layered body of the present invention is superior in moist heat resistance and smoothness and has wrinkles as compared with a substrate having a substrate made of triacetyl cellulose (TAC) because the substrate contains an acrylic resin. It can prevent suitably. In the present specification, “acrylic resin” means an acrylic resin and / or a methacrylic resin.

<Acrylic base material>
Although it does not specifically limit as an acrylic resin which an acrylic base material contains, For example, what is polymerized by combining 1 type (s) or 2 or more types of (meth) acrylic-acid alkylester is preferable, More specifically, (meth) Those obtained using methyl acrylate are preferred. Moreover, as an acrylic resin, it describes in Unexamined-Japanese-Patent No. 2000-230016, Unexamined-Japanese-Patent No. 2001-151814, Unexamined-Japanese-Patent No. 2002-120326, Unexamined-Japanese-Patent No. 2002-254544, Unexamined-Japanese-Patent No. 2005-146084 etc., for example. Can be mentioned. You may use what has ring structures, such as an acrylic resin which has a lactone ring structure, and an acrylic resin which has an imide ring structure.

The acrylic resin preferably has a glass transition point (Tg) of 100 to 150 ° C, more preferably 105 to 135 ° C, and most preferably 110 to 130 ° C. When the glass transition point (Tg) of the acrylic resin is 110 ° C. or higher, the primer layer is less likely to be damaged by the solvent contained in the primer layer forming composition, while the primer temperature is 150 ° C. or lower. It is easy to form irregularities at the interface with the layer.
The acrylic base material may contain a resin other than the acrylic resin, but the acrylic resin ratio in the acrylic base material is preferably 80% by mass or more, and more preferably 90% by mass or more.

As thickness of the said acrylic base material, it is preferable that it is 20-300 micrometers, More preferably, an upper limit is 200 micrometers and a minimum is 30 micrometers. When the thickness of the acrylic substrate is 20 μm or more, wrinkles are not easily generated in the optical laminate of the present invention. On the other hand, when the thickness is 300 μm or less, the optical laminate of the present invention is thinned, such as light transmittance. Excellent optical properties.
The acrylic substrate is preferably a stretched acrylic substrate. By setting it as an extending | stretching acrylic base material, the intensity | strength and dimensional stability of a base material can be made favorable.

The acrylic base material is manufactured, for example, by stretching a pellet (chip) made of a conditioned acrylic resin in the longitudinal direction while cooling after cooling by general melt extrusion, and then stretching in the lateral direction. be able to.
In the melt-extrusion step, a single-axis, bi-axis, or two-axis or more screw can be used, and the rotation direction, rotation speed, and melting temperature of the screw can be arbitrarily set.
The stretching is preferably performed so as to have a desired thickness after stretching. Moreover, although a draw ratio is not limited, 1.2 times or more and 4.5 times or less are preferable. The temperature and humidity during stretching are arbitrarily determined. The stretching method may be a general method.
The acrylic substrate may contain acrylic rubber particles, an antioxidant, an ultraviolet absorber, a plasticizer, and the like.

  In the present invention, the acrylic substrate may be subjected to surface treatment such as saponification treatment, glow discharge treatment, corona discharge treatment, ultraviolet (UV) treatment, and flame treatment without departing from the spirit of the present invention. Good.

<Primer layer>
The primer layer is a cured product of an ionizing radiation curable resin composition A containing 50 to 100% by mass (solid content) of polyalkylene glycol di (meth) acrylate. Here, in this specification, the ionizing radiation curable resin composition indicates an electron beam curable resin composition and / or an ultraviolet curable resin composition.
The ionizing radiation curable resin composition A may further contain a photopolymerizable monomer other than polyalkylene glycol di (meth) acrylate, a photopolymerizable oligomer, a photopolymerizable polymer, etc., and an ultraviolet curable resin composition. If it is a product, it contains an initiator.

(Polyalkylene glycol di (meth) acrylate)
The polyalkylene glycol di (meth) acrylate preferably has a molecular weight of 180 to 1000, more preferably a molecular weight of 200 to 750, and particularly preferably a molecular weight of 220 to 450. When the molecular weight of the polyalkylene glycol di (meth) acrylate is within the above range, it is preferable from the viewpoint of suppressing the generation of interference fringes and the adhesion between the acrylic base material and the primer layer.
Polyalkylene glycol di (meth) acrylates include polyethylene glycol di (meth) acrylates such as diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, and dipropylene glycol. Polybutylene glycol di (meth) such as polypropylene glycol di (meth) acrylate such as di (meth) acrylate and dibutylene glycol di (meth) acrylate, tributylene glycol di (meth) acrylate, tetrabutylene glycol di (meth) acrylate An acrylate is mentioned.
The compounding amount of the polyalkylene glycol di (meth) acrylate in the ionizing radiation curable resin composition A is a solid content and needs to be 50 to 100% by mass, and particularly preferably 70 to 100% by mass.
In addition, when other functional components such as a refractive index adjusting material or an antistatic material are added to the primer layer, the functional component does not exist in the lower portion of the primer layer as shown in FIG. It is presumed that the material component of the acrylic base material dissolved with the movement of volatilization of the solvent to be described later flows out into the primer layer to form irregularities at the interface of the acrylic base material-primer layer. In addition, due to this, moderate unevenness is generated at the interface, not only the adhesiveness is good and the interference fringe prevention property is good, but also the intended function (antistatic property, high refractive index property, low refractive index property). Etc.) is also preferable in terms of easy expression.

(Photopolymerizable polymer)
As the photopolymerizable polymer, those having a (meth) acryloyl group as a functional group are preferred, those having 10 to 250 functional groups are preferred, those having 10 to 100 are more preferred, and those having 10 to 50 are further preferred. preferable.
The weight average molecular weight of the photopolymerizable polymer is preferably 10,000 to 100,000, and more preferably 12,000 to 40,000.
The compounding amount of the photopolymerizable polymer in the ionizing radiation curable resin composition A is a solid content, preferably 0 to 40% by mass, and more preferably 0 to 30% by mass.

(Photopolymerizable oligomer)
As the photopolymerizable oligomer, those having two or more functional groups are used, those having a (meth) acryloyl group as a functional group are preferable, those having 2 to 30 functional groups are preferable, and those having 2 to 20 functional groups are preferable. More preferred is 3-15.
The weight average molecular weight of the photopolymerizable oligomer is preferably 1,000 to 10,000, and more preferably 1,500 to 10,000.
The compounding amount of the photopolymerizable oligomer in the ionizing radiation curable resin composition A is a solid content, preferably 0 to 40% by mass, and more preferably 0 to 30% by mass.

(Photopolymerizable monomer)
Examples of the photopolymerizable monomer include those having one or more unsaturated bonds such as a compound having a (meth) acryloyl group other than polyalkylene glycol di (meth) acrylate. Examples of monofunctional monomers having one unsaturated bond include ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone, and a high refractive index material (o-phenylphenol EO-modified acrylate). Etc. Examples of the polyfunctional monomer having two or more unsaturated bonds include polymethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, Dipentaerythritol penta (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, etc., and polyfunctional compounds obtained by modifying these with ethylene oxide (EO) or the like A reaction product such as a functional compound and (meth) acrylate (for example, poly (meth) acrylate ester of polyhydric alcohol) can be used.
By using a monofunctional monomer, the refractive index can be easily adjusted and a primer layer having a higher refractive index can be formed. On the other hand, when a polyfunctional monomer is used, the hardness is improved.
In the present specification, “(meth) acrylate” refers to methacrylate and acrylate.
The molecular weight of the photopolymerizable monomer is preferably 200 to 1,000, and more preferably 250 to 750.
The compounding amount of the photopolymerizable monomer in the ionizing radiation curable resin composition A is a solid content, preferably 0 to 40% by mass, and more preferably 0 to 30% by mass.

The ionizing radiation curable resin composition A preferably further contains a solvent.
It is preferable to select a solvent that appropriately swells the acrylic substrate. However, the acrylic base material swells with almost all kinds of solvents, unlike the TAC base material that is often used conventionally. Therefore, since the influence by the solvent is strong and it may break if the degree of swelling is too strong, by selecting the following solvent, it can be swollen appropriately and the resin component constituting the base material and the resin constituting the resin layer The balance in which the components move is moderate, and a preferable ridgeline can be obtained at the interface.
Furthermore, the said solvent can be selected and used according to the kind and solubility of the resin component to be used. As such a solvent, alcohols (methanol, ethanol, isopropanol, 1-butanol) are preferable, and in each of the other solvent types, those having a higher carbon number tend to be good, and among them, the evaporation rate is fast. Tend to be good. For example, in the case of ketones, methyl isobutyl ketone, in the case of aromatic hydrocarbons, toluene, in the case of glycols, propylene glycol monomethyl ether and the like can be exemplified, and a mixed solvent thereof may be used.
In particular, in the present invention, the compatibility with the resin and the coating property are excellent, the unique uneven shape of the present application is formed at the acrylic substrate-primer layer interface, and further, there is no problem that the substrate is cut during processing. In particular, those containing at least one selected from methyl isobutyl ketone, isopropanol, 1-butanol, and propylene glycol monomethyl ether are preferable. With these solvents, the acrylic base material can be appropriately swollen without cracking.
Conversely, esters (methyl acetate, ethyl acetate, propyl acetate, butyl acetate, etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone, diacetone alcohol), cellosolves, ethers (dioxane, tetrahydrofuran, propylene glycol monomethyl ether acetate) ), Aliphatic hydrocarbons (hexane, etc.), aromatic hydrocarbons (xylene), halogenated carbons (dichloromethane, dichloroethane, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfoxides (Dimethyl sulfoxide, etc.) and amides (dimethylformamide, dimethylacetamide, etc.) are preferably not used when tension is applied to the substrate because the acrylic substrate may swell excessively.
Although it does not specifically limit as a content rate of the solvent in the said ionizing-radiation-curable resin composition A, For example, about the above-mentioned preferable solvent, with respect to 100 mass parts of solid content of the ionizing-radiation-curable resin composition A, 30- The amount is preferably 300 parts by mass, and more preferably 100 to 220 parts by mass. When the content of the solvent is 30 parts by mass or more with respect to 100 parts by mass of the solid content of the ionizing radiation curable resin composition A, the unevenness of the acrylic substrate-primer layer interface becomes remarkable, and the acrylic substrate and the primer layer From the viewpoint of suppressing adhesion and interference fringes, and being 300 parts by mass or less, it is preferable from the viewpoint of suppressing generation of haze.

It is preferable that the manufacturing method of the optical laminated body of this invention has the following 1st process-4th process, and also when it has a 5th process, it is preferable from a viewpoint which provides hardness to an optical laminated body.
(First step)
An ionizing radiation curable resin composition A containing 50% or more of polyalkylene glycol di (meth) acrylate is applied to an acrylic substrate.
(Second step)
The acrylic substrate is swollen by the solvent, monomer, etc. in the ionizing radiation curable resin composition A.
(Third process)
While drying the solvent at an appropriate drying temperature, the acrylic base material swells, and the material component in the acrylic base material and the component in the ionizing radiation curable resin composition A move to each other, whereby the acrylic base material / Unevenness is formed at the primer layer interface.
(Fourth process)
Irradiating with ionizing radiation cures the ionizing radiation curable resin composition A to cure the primer layer.
(Fifth process)
On the primer layer, an ionizing radiation curable resin composition B is separately applied, dried, and cured by irradiation with ionizing radiation to form a hard coat layer.

In the method for producing an optical layered body of the present invention, the following conditions (i) to (iii) are satisfied in order that the acrylic base material can be processed without being cut and there is no interference fringe and good adhesion. It is preferable.
(I) The ionizing radiation curable resin composition A contains 50 to 100% by mass of polyalkylene glycol di (meth) acrylate.
(Ii) The ionizing radiation curable resin composition A contains a solvent that appropriately swells the acrylic substrate, and the acrylic substrate does not break during processing.
(Iii) The drying temperature in the third step is 40 ° C to 90 ° C.
In addition, even if the solvent of the ionizing radiation curable resin composition A is an appropriate type as described above, if the drying temperature exceeds 90 ° C., the attack force of the solvent increases, so that the acrylic base material is easily cut during processing. There is a case.
By satisfying all of the above conditions (i) to (iii), it becomes possible to easily produce an optical laminate that has favorable irregularities at the interface between the acrylic substrate and the primer layer, and as a result, interference fringe prevention and adhesion are good. It becomes.

The ionizing radiation curable resin composition A may further contain a solvent-drying resin. By using the solvent-drying resin in combination, film defects on the coated surface can be effectively prevented. In addition, the said solvent dry type resin means resin which becomes a film only by drying the solvent added in order to adjust solid content at the time of coating, such as a thermoplastic resin.
The solvent-drying resin is not particularly limited, and generally a thermoplastic resin can be 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, from the viewpoints of film forming properties, transparency, and weather resistance, styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters, etc.) and the like are preferable.

  The initiator is not particularly limited, and known ones can be used. For example, specific examples of the photopolymerization initiator include acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime ester, Examples include thioxanthones, propiophenones, benzyls, benzoins, and 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 photopolymerization initiator, when the photopolymerizable monomer / oligomer / polymer is a resin system having a radically polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether, etc. are used alone or It is preferable to use a mixture, and 1-hydroxy-cyclohexyl-phenyl-ketone is particularly preferable because it is compatible with an ionizing radiation curable resin and has little yellowing. When the photopolymerizable monomer / oligomer / polymer has a cationic polymerizable functional group, the photopolymerization initiator may be an aromatic diazonium salt, aromatic sulfonium salt, aromatic iodonium salt, metallocene compound, benzoin sulfone. It is preferable to use acid esters alone or as a mixture.

The content of the initiator in the ultraviolet curable resin composition is 1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the photopolymerizable monomer, photopolymerizable oligomer and photopolymerizable polymer. preferable. When the content of the initiator is 1 part by mass or more, it is preferable from the viewpoint of the hardness of the primer layer in the optical layered body, and when it is 10 parts by mass or less, the resin deterioration due to excessive remaining of the initiator is suppressed and the cost is reduced. The pencil hardness of the surface of the target primer layer and the hard coat layer described later can be obtained.
The more preferable lower limit of the content of the initiator is 2 parts by mass with respect to 100 parts by mass of the total amount of the photopolymerizable monomer, the photopolymerizable oligomer, and the photopolymerizable polymer, and the more preferable upper limit is 8 parts by mass. is there. The said effect is made more reliable because content of the said initiator exists in this range.

By containing a functional component in the ionizing radiation curable resin composition A, a function can be further imparted to the primer layer.
Examples of the functional component include those used for ordinary optical sheets such as an antistatic agent, a refractive index adjusting agent, an antifouling agent, a slip agent, an antiglare agent, and a hard coatability imparting agent.

The ionizing radiation curable resin composition A may contain an antistatic agent.
As the antistatic agent, an organic type is preferable, and more specifically, ionic ones such as lithium ion salts, quaternary ammonium salts, ionic liquids, and electronic conductivity such as polythiophene, polyaniline, polypyrrole, polyacetylene, etc. Can be mentioned.
Further, the ionizing radiation curable resin composition A may contain an antifouling agent such as fluorine or silicone.
When using the said functional component, it is preferable that the content is 1-30 mass% with respect to the total mass of the total solid in the ionizing radiation-curable resin composition A.
In the optical laminate of the present invention, when the primer layer is formed using the ionizing radiation curable resin composition A containing the antistatic agent (that is, when the primer layer contains the antistatic agent), Due to the combination with the alkylene glycol di (meth) acrylate, the antistatic agent is localized on the upper surface of the primer layer for the above reasons, so that the antistatic performance is further improved. Moreover, when a primer layer is formed using the ionizing radiation curable resin composition A containing ultrafine particles such as silica and alumina as a hard coatability-imparting agent (that is, when the primer layer contains a hardcoat property-imparting agent). By the combination with the above-mentioned polyalkylene glycol di (meth) acrylate, the hard coat property-imparting agent is localized on the upper surface of the primer layer for the reasons described above, so that the hard coat performance is further improved.

  The method for preparing the ionizing radiation curable resin composition A is not particularly limited as long as each component can be mixed uniformly. For example, the ionizing radiation curable resin composition A can be prepared using a known apparatus such as a paint shaker, a bead mill, a kneader, or a mixer.

  Moreover, it does not specifically limit as a method of apply | coating the said ionizing radiation curable resin composition A on the said acrylic base material, For example, a spin coat method, a dip method, a spray method, a die coat method, a bar coat method, a gravure coat method And publicly known methods such as a roll coater method, a meniscus coater method, a flexographic printing method, a screen printing method, and a pead coater method.

The coating film formed by applying the ionizing radiation curable resin composition A on the acrylic substrate is preferably heated and dried as necessary, and cured by irradiation with active energy rays or the like.
The drying time in the drying step is preferably 20 seconds to 2 minutes, more preferably 30 seconds to 1 minute. Moreover, the drying temperature in a drying process becomes like this. Preferably it is 40-90 degreeC, More preferably, it is 50-80 degreeC. When the drying temperature is less than 40 ° C., the processed optical laminate has a large amount of residual solvent, and an uncured portion is generated in the next curing step, and the adhesiveness is lowered due to the influence. In the case of an acrylic base material, there is a feature that it is easy to swell in almost any solvent. For this reason, when the drying temperature is outside the preferred range and exceeds 100 ° C., the force against swelling of the solvent is improved, and it is easy to break when the tension applied during coating processing exceeds 2.2 N / cm. Therefore, in the present invention, it is preferable to select an appropriate solvent and an appropriate drying temperature.

Examples of the active energy ray irradiation include irradiation with ultraviolet rays or electron beams.
Specific examples of the ultraviolet light source in the ultraviolet irradiation include light sources such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, and a metal halide lamp. Moreover, as a wavelength of an ultraviolet-ray, the wavelength range of 190-380 nm can be used.
Specific examples of electron beam sources in the above-mentioned electron beam irradiation include various types of electron beam accelerators such as cockcroft-wald type, bande graft type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type. Can be mentioned.

  In addition, since the preferable film thickness (at the time of hardening) of the said primer layer is 0.5-100 micrometers, More preferably, it is 0.8-13 micrometers, Since curl prevention property and crack prevention property are especially excellent, Most preferably, it is 0.8-4 micrometers. It is a range. The film thickness of the hard coat layer is an average value (μm) obtained by observing a cross section with an electron microscope (SEM, TEM, STEM) and measuring any 10 points.

  In addition, the optical laminate of the present invention is one or more selected from a low refractive index layer, a hard coat layer, an antifouling layer, an antiglare layer, an antistatic layer, and a high refractive index layer directly on the primer layer. You may have.

<Hard coat layer>
The hard coat layer is formed on the primer layer, and preferably comprises a cured product of the ionizing radiation curable resin composition B.
The hardness of the hard coat layer is preferably H or higher, more preferably 2H or higher, in a pencil hardness test (load 4.9 N) according to JIS K5600-5-4 (1999). The hard coat layer may contain a functional component.

The details of the ionizing radiation curable resin composition B forming the hard coat layer are the same as those of the ionizing radiation curable resin composition A described above except that polyalkylene glycol di (meth) acrylate is not an essential component.
Further, in the ionizing radiation curable resin composition B, the blending amount of the photopolymerizable monomer (particularly the polyfunctional monomer) is preferably 30 to 100% by mass, more preferably 40 to 90% by mass, and 50 More preferably, it is -80 mass%. At that time, the remainder of the ionizing radiation curable resin composition B is preferably at least one of a photopolymerizable oligomer and a photopolymerizable polymer.
Moreover, the formation method of a hard-coat layer is the same as that of the above-mentioned primer layer. The details of the other hard coat layers are also the same as those of the primer layer described above.
In the present invention, it is preferable to laminate a hard coat layer on the primer layer. The primer layer itself may be made to have high hardness by using the ionizing radiation curable resin composition A having a high ratio of other functional monomers of 3 or more, or by adding a hard coat imparting agent. When the hardness of 2H or higher is used directly, that is, when the primer layer is made of a material having a polyfunctional reactive functional group, the acrylic base material is easily cracked, for example, when some pressure is applied to the hard coat layer. Has the disadvantages. Therefore, in the optical layered body of the present invention, by providing the primer layer between the hard coat layer, the impact of the hard coat layer is not directly transmitted to the acrylic base material, but has a buffering action and is more preferable hard Coat properties. The primer layer / hard coat layer can also improve the hardness as compared with the case where only the hard coat layer is laminated.
However, in the case of laminating a hard coat layer or the like, a new interface is formed between the primer layer, that is, the portion that causes interference fringes increases. In this case, it is important that the refractive index of the layer to be stacked is as close as possible to the layer below it. Therefore, in order to maintain the interference fringe prevention property satisfactorily, the refractive index of the hard coat layer is preferably almost the same as the refractive index of the primer layer, and the preferable refractive index difference with the primer layer is 0.03. It is as follows.
The film thickness of the hard coat layer is preferably 1 to 20 μm, and more preferably 3 to 15 μm.

<Low refractive index layer>
The optical layered body of the present invention preferably further has a low refractive index layer on the hard coat layer.
The low refractive index layer is preferably 1) a resin containing inorganic fine particles of low refractive index such as silica or magnesium fluoride, 2) a fluorine-based resin which is a low refractive index resin, 3) silica or magnesium fluoride, etc. It is formed using a composition for forming a low refractive index layer containing either a fluorine-based resin containing low refractive index inorganic fine particles, 4) a low refractive index inorganic thin film such as silica or magnesium fluoride, and the like. For resins other than fluorine-based resins, the same resins as the acrylic resins described above can be used.
Moreover, it is preferable that the silica mentioned above is a hollow silica fine particle, and such a hollow silica fine particle can be produced by, for example, a production method described in Examples of JP-A-2005-099778.
These low refractive index layers preferably have a refractive index of 1.47 or less, particularly 1.42 or less. In addition, the thickness of the low refractive index layer is not limited, but it may be set appropriately from the range of about 10 nm to 1 μm.

  As the fluororesin, a polymerizable compound containing a fluorine atom in at least a molecule or a polymer thereof can be used. Although it does not specifically limit as a polymeric compound, For example, what has hardening reactive groups, such as a functional group hardened | cured by ionizing radiation, and a polar group thermally cured, is preferable. Moreover, the compound which has these reactive groups simultaneously may be sufficient. In contrast to this polymerizable compound, a polymer has no reactive groups as described above.

  As the polymerizable compound having a functional group that is cured by ionizing radiation, fluorine-containing monomers having an ethylenically unsaturated bond can be widely used. More specifically, to illustrate fluoroolefins (eg, fluoroethylene, vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene, perfluorobutadiene, perfluoro-2,2-dimethyl-1,3-dioxole, etc.) Can do. As those having a (meth) acryloyloxy group, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3,3-pentafluoropropyl (meth) acrylate, 2- (perfluorobutyl) ) Ethyl (meth) acrylate, 2- (perfluorohexyl) ethyl (meth) acrylate, 2- (perfluorooctyl) ethyl (meth) acrylate, 2- (perfluorodecyl) ethyl (meth) acrylate, α-trifluoro (Meth) acrylate compounds having a fluorine atom in the molecule, such as methyl methacrylate and α-trifluoroethyl methacrylate; a C 1-14 fluoroalkyl group having at least 3 fluorine atoms in the molecule, fluoro A cycloalkyl group or a fluoroalkylene group and at least two (medium There are also fluorine-containing polyfunctional (meth) acrylic acid ester compounds having an acryloyloxy group.

Preferable examples of the thermosetting polar group include hydrogen bond forming groups such as a hydroxyl group, a carboxyl group, an amino group, and an epoxy group. These are excellent not only in adhesion to the coating film but also in affinity with inorganic ultrafine particles such as silica. Examples of the polymerizable compound having a thermosetting polar group include 4-fluoroethylene-perfluoroalkyl vinyl ether copolymer; fluoroethylene-hydrocarbon vinyl ether copolymer; epoxy, polyurethane, cellulose, phenol, polyimide, and the like. Examples include fluorine-modified products of each resin.
Examples of the polymerizable compound having both a functional group curable by ionizing radiation and a polar group curable by heat include acrylic or methacrylic acid moieties and fully fluorinated alkyl, alkenyl, aryl esters, fully or partially fluorinated vinyl ethers, fully Alternatively, partially fluorinated vinyl esters, fully or partially fluorinated vinyl ketones and the like can be exemplified.

Moreover, as a fluorine resin, the following can be mentioned, for example.
Polymer of monomer or monomer mixture containing at least one fluorine-containing (meth) acrylate compound of a polymerizable compound having an ionizing radiation curable group; at least one fluorine-containing (meth) acrylate compound; and methyl (meth) Copolymers with (meth) acrylate compounds that do not contain fluorine atoms in the molecule such as acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate; fluoroethylene , Fluorine-containing compounds such as vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, 3,3,3-trifluoropropylene, 1,1,2-trichloro-3,3,3-trifluoropropylene, hexafluoropropylene Monomer homopolymer or Copolymer such as. Silicone-containing vinylidene fluoride copolymers obtained by adding a silicone component to these copolymers can also be used. The silicone components in this case include (poly) dimethylsiloxane, (poly) diethylsiloxane, (poly) diphenylsiloxane, (poly) methylphenylsiloxane, alkyl-modified (poly) dimethylsiloxane, azo group-containing (poly) dimethylsiloxane, Dimethyl silicone, phenylmethyl silicone, alkyl aralkyl modified silicone, fluorosilicone, polyether modified silicone, fatty acid ester modified silicone, methyl hydrogen silicone, silanol group containing silicone, alkoxy group containing silicone, phenol group containing silicone, methacryl modified silicone, acrylic Modified silicone, amino modified silicone, carboxylic acid modified silicone, carbinol modified silicone, epoxy modified silicone, mercapto modified silicone Over emissions, fluorine-modified silicones, polyether-modified silicone and the like. Of these, those having a dimethylsiloxane structure are preferred.

  Furthermore, non-polymers or polymers composed of the following compounds can also be used as the fluororesin. That is, a fluorine-containing compound having at least one isocyanato group in the molecule is reacted with a compound having at least one functional group in the molecule that reacts with an isocyanato group such as an amino group, a hydroxyl group, or a carboxyl group. Compound obtained: a compound obtained by reacting a fluorine-containing polyol such as fluorine-containing polyether polyol, fluorine-containing alkyl polyol, fluorine-containing polyester polyol, fluorine-containing ε-caprolactone modified polyol with a compound having an isocyanato group Can be used.

  Moreover, the composition for low refractive index layer formation may contain each thermoplastic resin as described above with the polymeric compound and polymer which have the above-mentioned fluorine atom. Furthermore, various additives and solvents can be used as appropriate in order to improve the curing agent for curing reactive groups and the like, to improve the coating property, and to impart antifouling properties.

  In the formation of the low refractive index layer, the viscosity of the composition for forming a low refractive index layer is 0.5 to 5 mPa · s (25 ° C.), preferably 0.7 to 3 mPa · s (at which preferable coating properties are obtained. 25 ° C.). An antireflection layer excellent in visible light can be realized, a uniform thin film with no coating unevenness can be formed, and a low refractive index layer particularly excellent in adhesion can be formed.

  The resin curing means may be the same as the curing means in the hard coat layer described above. When a heating means is used for the curing treatment, a thermal polymerization initiator that generates, for example, radicals to start polymerization of the polymerizable compound by heating is added to the composition for forming a low refractive index layer. Is preferred.

The optical layered body of the present invention preferably has a total light transmittance of 80% or more. If it is less than 80%, color reproducibility and visibility may be impaired when mounted on an image display device, and a desired contrast may not be obtained. The total light transmittance is more preferably 90% 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% or less. When it is 1% or less, desired optical characteristics can be obtained, and there is no deterioration in optical characteristics when the optical laminate of the present invention is placed on the image display surface. The haze is more preferably 0.8% or less, and further preferably 0.5% or less.
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 polarizing plate of the present invention is formed by laminating the optical laminate of the present invention on at least one surface of a polarizing film.
The polarizing film is not particularly limited, and for example, a polyvinyl alcohol film, a polyvinyl formal film, a polyvinyl acetal film, an ethylene-vinyl acetate copolymer saponified film, which is dyed and stretched with iodine or the like can be used. In the laminating process between the polarizing film and the optical laminate, it is preferable to saponify the acrylic base material. By the saponification treatment, the adhesiveness is improved and an antistatic effect can be obtained.

The present invention also provides an image display device comprising the optical laminate and / or the polarizing plate.
Examples of the image display device include a television, a computer, an LCD, a PDP, an FED, an ELD (organic EL, inorganic EL), a CRT, a tablet PC, electronic paper, a mobile phone, and the like, and further used for an image display device and the like. It can also be suitably used for a touch panel.

  The LCD, which is a typical example of the above, includes a transmissive display body and a light source device that irradiates the transmissive display body from the back. When the image display device of the present invention is an LCD, the optical laminate of the present invention and / or the polarizing plate of the present invention is formed on the surface of the transmissive display. However, in the case of an image display device equipped with a touch panel, it can be used not only on the surface but also as a transparent substrate constituting the touch panel.

  The LCD, which is a typical example of the above, includes a transmissive display body and a light source device that irradiates the transmissive display body from the back. When the image display device of the present invention is an LCD, the optical laminate of the present invention and / or the polarizing plate of the present invention is formed on the surface of the transmissive display. In addition, in the case of an image display device equipped with a touch panel or an LCD, it can be used not only as a surface but also as a transparent substrate constituting the inside of the device.

  In the liquid crystal display device of the present invention, the light source of the light source device irradiates from the lower side of the optical laminate or the polarizing plate. Note that a retardation plate may be inserted between the liquid crystal display element and the polarizing plate. An adhesive layer may be provided between the layers of the liquid crystal display device as necessary.

Here, in the case where the present invention is a liquid crystal display device having the above optical laminate, the backlight light source in the liquid crystal display device is not particularly limited, but is preferably a white light emitting diode (white LED). The display device is preferably a VA mode or IPS mode liquid crystal display device including a white light emitting diode as a backlight light source.
The white LED is an element that emits white by combining a phosphor with a phosphor system, that is, a light emitting diode that emits blue light or ultraviolet light using a compound semiconductor. In particular, white light-emitting diodes, which consist of light-emitting elements that combine blue light-emitting diodes using compound semiconductors with yttrium, aluminum, and garnet yellow phosphors, have a continuous and broad emission spectrum, so they have anti-reflection performance. In addition, it is effective for improving the contrast of a bright place and is excellent in luminous efficiency, and thus is suitable as the backlight light source in the present invention. Further, since white LEDs with low power consumption can be widely used, it is possible to achieve an energy saving effect.
The VA (Vertical Alignment) mode refers to a dark display in which liquid crystal molecules are aligned so as to be perpendicular to the substrate of the liquid crystal cell when no voltage is applied, and the liquid crystal molecules are collapsed when a voltage is applied. This is an operation mode showing bright display.
The IPS (In-Plane Switching) mode is a method in which display is performed by rotating the liquid crystal within the substrate surface by a horizontal electric field applied to a pair of comb electrodes provided on one substrate of the liquid crystal cell. is there.

  The PDP as the image display device has a surface glass substrate on which an electrode is formed on the surface and a discharge gas sealed between the surface glass substrate to form the electrode and minute grooves on the surface. And a rear glass substrate on which red, green and blue phosphor layers are formed in the groove. When the image display device of the present invention is a PDP, the above-mentioned optical laminate is provided on the surface of the surface glass substrate or the front plate (glass substrate or film substrate).

  The above image display device is a zinc sulfide or diamine substance that emits light when a voltage is applied: a light emitting material is deposited on a glass substrate, and an ELD device that performs display by controlling the voltage applied to the substrate, or converts an electrical signal into light Alternatively, it may be an image display device such as a CRT that generates an image visible to human eyes. In this case, the optical laminated body described above is provided on the outermost surface of each display device as described above or the surface of the front plate.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by this example.

Example 1
(Manufacture of acrylic substrate 1)
Pellets made of a copolymer of methyl methacrylate and methyl acrylate (glass transition point: 130 ° C.) were melt-kneaded and the polymer was extruded from the gap of the die by a melt extrusion method while removing foreign matters through a filter. Next, while cooling the polymer, the polymer was stretched 1.2 times in the longitudinal direction, and then stretched 1.5 times in the transverse direction to obtain an acrylic substrate 1 having a thickness of 40 μm.

(Preparation of primer layer forming composition)
100 parts by mass of tetraethylene glycol diacrylate (manufactured by Toagosei Co., Ltd., “M240”) and 4 parts by mass of an initiator (manufactured by BASF, “Irg184”) are dissolved in 150 parts by mass of methyl isobutyl ketone to form a primer layer. A composition was prepared.
Table 1 shows the composition of the primer layer forming composition.

(Preparation of hard coat layer forming composition 1)
50 parts by mass of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.), 50 parts by mass of urethane acrylate (manufactured by Nippon Synthetic Chemical Industry, “UV1700B”, 10 functional, weight average molecular weight: 2,000), and initiator 4 parts by mass (manufactured by BASF, “Irg184”) was dissolved in 150 parts by mass of methyl isobutyl ketone to prepare composition 1 for forming a hard coat layer.

(Manufacture of optical laminates)
A primer layer-forming composition is applied onto an acrylic substrate by a die coating method, dried at 70 ° C. for 1 minute to evaporate the solvent, and the coating amount after drying is 4 g / m ² (dry film thickness 3 The primer layer was formed to be 5 μm). The obtained coating film was irradiated with ultraviolet rays at a dose of 70 mJ / cm ² to make the coating film semi-cured (half-cured state).
Next, on the primer layer formed as described above, the hard coat layer-forming composition 1 is applied by a die coating method, and dried at 70 ° C. for 1 minute to evaporate the solvent. The hard coat layer 1 was formed so that the coating amount was 8 g / m ² (dry film thickness 7 μm). The obtained coating film was irradiated with ultraviolet rays at an ultraviolet irradiation amount of 200 mJ / cm ² to completely cure the coating film (full cure state) to obtain an optical laminate.

Examples 2 to 16, Comparative Examples 1 to 9, and Reference Examples 1 to 7
An optical laminate was obtained in the same manner as in Example 1 except that the composition of the primer layer forming composition and the drying temperature were changed to those shown in Tables 1 and 2.

Example 17
As the hard coat layer forming composition, instead of the hard coat layer forming composition 1 described above, the same composition as in Example 1 was used except that the hard coat layer forming composition 2 prepared as follows was used. Thus, an optical laminate was obtained.
(Preparation of hard coat layer forming composition 2)
30 parts by mass of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.), 46 parts by mass of urethane acrylate (manufactured by Arakawa Chemical Industries, Ltd., “BS577”, hexafunctional, weight average molecular weight: 1,000), monomer (Toagosei Co., Ltd.) "M315", trifunctional), 20 parts by mass, quaternary ammonium salt-containing oligomer (manufactured by Taisei Fine Chemical Co., Ltd., "1SX3000") and 4 parts by mass of initiator (BASF, "Irg184") Part was dissolved in 130 parts by mass of methyl isobutyl ketone and 20 parts by mass of N-butanol to prepare composition 2 for forming a hard coat layer.
The optical layered body obtained in Example 17 has antistatic properties because the hard coat layer contains an antistatic agent.

  The following evaluation was performed about the optical laminated body obtained in Examples 1-17, Comparative Examples 1-9, and Reference Examples 1-7. The results are shown in Tables 1 and 2.

(Adhesion)
In accordance with JIS K 5600, a 100 mm grid with 1 mm square is put in the hard coat layer of the optical laminate, and a continuous peel test is performed 5 times using Nichiban Co., Ltd. industrial 24 mm cello tape (registered trademark). The number of remaining squares was measured.
Depending on the number of squares that were not peeled off, evaluation was performed as follows. ○ A level or higher is a good product.
A: 90-100
B: 80-89
C: 50-79
D: Less than 50

(Interference fringes)
After pasting a black tape on the surface opposite to the hard coat layer of the optical laminate, the presence or absence of interference fringes was evaluated visually under a three-wavelength tube fluorescent lamp. The case where the interference fringes could not be visually recognized was designated as A, the case where the interference fringes could be visually recognized as B, and the case where the interference fringes were visually recognized as C.

(Manufacturing processability)
When the primer layer forming composition was applied on an acrylic substrate and dried, a tensile test was performed. The degree of pulling was 2.2 N / cm.
As a result, the case where it was not cut in the pulled fold was evaluated as “good”, and the case where even a slight break occurred and caused a problem in manufacturing processing was evaluated as “bad”.
Optical laminates with “bad” manufacturing processability have weakened physical properties of the substrate itself, so the pencil hardness (JIS K5600-5-4) is 2H or higher even when the primer layer, hard coat layer, etc. are cured. Does not appear.

(Surface resistance)
About each optical laminated body produced by the said Example and comparative example, the surface resistance value was measured using the surface resistance value measuring device (High Lester HT-210, Mitsubishi Oil Chemical Co., Ltd. product).

PEG di (meth) acrylate 1: tetraethylene glycol diacrylate (manufactured by Toagosei Co., Ltd., “M240”, molecular weight: 286)
PEG di (meth) acrylate 2: triethylene glycol dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., “Light Ester 3EG”, molecular weight: 270)
PEG di (meth) acrylate 3: tetraethylene glycol dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., “Light Ester 4EG”, molecular weight: 314)
Maleimide polymer: (manufactured by Toagosei Co., Ltd., “UVT302”)
PETA: Pentaerythritol triacrylate polyfunctional polymer: “BS371” manufactured by Arakawa Chemical Industries
Multifunctional oligomer: “R1403” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
Monomer 1: Dipentaerythritol hexaacrylate, Nippon Kayaku Co., Ltd. monomer 2: o-phenylphenol EO-modified acrylate, Shin-Nakamura Chemical Co., Ltd. quaternary ammonium salt: “Colcoat NR121X”
ATO particle: Methyl isobutyl ketone dispersion of antimony-doped tin oxide “EPT5DL2MIBK” manufactured by Mitsubishi Materials Electronics Chemical Co., Ltd.
Reactive silica: Nissan Chemical Industries, Ltd., “MIBKSD”, average particle size: 12 nm
Zirconia: Zirconium oxide MEK dispersion (solid dispersion 30%, manufactured by Sakai Chemical Industry, "SZR-K 4 nm")
MIBK: methyl isobutyl ketone PGME: propylene glycol monomethyl ether MEK: methyl ethyl ketone

In addition, in manufacture of the optical laminated body in the said Examples 1-17, it passed through the following 1st processes-5th processes.
(First step)
An ionizing radiation curable resin composition A containing 50% or more of polyalkylene glycol di (meth) acrylate is applied to an acrylic substrate.
(Second step)
The acrylic substrate is swollen by the solvent, monomer, etc. in the ionizing radiation curable resin composition A.
(Third process)
While drying the solvent at an appropriate drying temperature, the acrylic base material swells, and the material component in the acrylic base material and the component in the ionizing radiation curable resin composition A move to each other, whereby the acrylic base material / Unevenness is formed at the primer layer interface.
(Fourth process)
Irradiating with ionizing radiation cures the ionizing radiation curable resin composition A to cure the primer layer.
(Fifth process)
On the primer layer, an ionizing radiation curable resin composition B is separately applied, dried, and cured by irradiation with ionizing radiation to form a hard coat layer.
For this reason, the acrylic base material which is the subject of the present invention was not cut at the time of processing, interference fringe prevention property and adhesion were good, and furthermore, an optical laminate having a pencil hardness of 2H or more was obtained.

  The optical laminate of the present invention is a cathode ray tube display (CRT), liquid crystal display (LCD), plasma display (PDP), electroluminescence display (ELD), touch panel, electronic paper, mobile phone display, etc. It can be suitably used for a display.

1. 1. Acrylic base material Primer layer 3. 3. Hard coat layer Acrylic substrate-primer layer interface

Claims (13)

An optical laminate having an acrylic base material and a primer layer in this order,
The optical layered product, wherein the primer layer is a cured product of an ionizing radiation curable resin composition A containing 50 to 100% by mass (solid content) of polyalkylene glycol di (meth) acrylate.   The optical laminate according to claim 1, wherein the acrylic substrate has a glass transition point (Tg) of 110 to 150 ° C.   3. The optical laminate according to claim 1, wherein a blending amount of the polyalkylene glycol di (meth) acrylate in the ionizing radiation curable resin composition A is 70 to 100% by mass (solid content).   The optical laminate according to any one of claims 1 to 3, wherein the polyalkylene glycol di (meth) acrylate has a molecular weight of 180 to 1,000.   The optical laminate according to any one of claims 1 to 4, wherein the acrylic substrate is a stretched acrylic substrate.   The optical layered product according to any one of claims 1 to 5, further comprising a functional layer on the surface of the primer layer opposite to the acrylic substrate side.   The optical laminate according to claim 6, wherein the functional layer is a hard coat layer and is a cured product of the ionizing radiation curable resin composition B.   The optical layered body according to any one of claims 1 to 7, wherein the primer layer contains a functional component.   The polarizing plate formed by laminating | stacking the optical laminated body in any one of Claims 1-8 on the at least one surface of a polarizing film.   An image display apparatus provided with the optical laminated body in any one of Claims 1-8, and / or the polarizing plate of Claim 9.   Applying an ionizing radiation curable resin composition A containing 50 to 100% by mass of polyalkylene glycol di (meth) acrylate in an amount of solid on an acrylic substrate, drying and curing to form a primer layer The method for producing an optical laminated body according to any one of claims 1 to 8.   The ionizing radiation curable resin composition A contains at least one selected from methyl isobutyl ketone, 1-butanol, propylene glycol monomethyl ether and isopropanol as a solvent, and has a drying temperature of 40 to 90 ° C. The manufacturing method of the optical laminated body of Claim 11.   The optical lamination according to claim 11 or 12, wherein an ionizing radiation curable resin composition B is further applied to a surface of the primer layer opposite to the acrylic substrate side, dried and cured to form a functional layer. Body manufacturing method.