JP2003071990A - Scratch-resistant substrate having antireflection properties and polarizing plate - Google Patents

Abstract

(57) [Abstract] [Purpose] An anti-reflection coating film having a hard cured film that is hard and scratch-resistant, has good light transmittance, is easy to manufacture, and has good interlayer adhesion is provided on the surface of a transparent substrate. Formed scratch-resistant substrate,
And a polarizing plate using the same. A scratch-resistant substrate having antireflection properties forms a lower coating film 2 made of a resin composition containing an ionizing radiation-curable resin on one or both surfaces of a transparent substrate 1. An upper coating film 3 made of an ionizing radiation-curable resin composition having a refractive index slightly lower than the refractive index of the ionizing radiation-curable resin composition of the lower coating film 2. It consists of an ionizing radiation-curable resin composition containing atoms.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scratch-resistant base material and a polarizing plate capable of preventing reflection of light on the surfaces of displays such as curved mirrors, rearview mirrors, goggles, window glasses and personal computers and word processors.

[0002]

2. Description of the Related Art Conventionally, transparent substrates such as glass and plastic have been used for curved mirrors, rearview mirrors, goggles, window glasses, displays for personal computers and word processors, and various other commercial displays. When observing visual information of objects, characters, and figures through a substrate, or an image from a reflective layer through a transparent substrate with a mirror, the surface of these transparent substrates is reflected by light, making it difficult to see the internal visual information. was there.

In particular, a polarizing element that functions as a light shutter is provided on the surface of a display body such as a liquid crystal display. However, since the polarizing element itself is inferior in scratch resistance, glass, a transparent plastic plate, Alternatively, the polarizing plate is formed by being protected by a transparent protective substrate such as a transparent plastic film. However, since the transparent protective substrate itself made of a plastic such as a transparent plastic plate or a transparent plastic film is also easily scratched, in recent years, such a polarizing plate having a scratch-resistant surface has been developed. As such a technique, for example, Japanese Patent Application Laid-Open No. 1-
There is one described in Japanese Patent No. 105738.

As a method of preventing reflection on such a transparent substrate, conventionally, a method of applying an antireflection coating on the surface of glass or plastic, MgF ₂ having a film thickness of about 0.1 μm on the surface of a transparent substrate such as glass, etc. The method of providing an ultra-thin film or metal vapor deposition film, coating the surface of plastics such as plastic lenses with an ionizing radiation curable resin, and then depositing S by vapor deposition.
There have been methods such as a method of forming a film of iO ₂ and MgF ₂ , and a method of forming a coating film having a low refractive index on a cured film of an ionizing radiation curable resin.

Film thickness of 0.1 μm formed on the glass
A thin film of MgF _{2 on} the order of will be further described. When incident light is vertically incident on the thin film, a specific wavelength is set to λ ₀ , the refractive index of the antireflection film for this wavelength is n ₀ , the thickness of the antireflection film is h, and the refractive index of the transparent substrate is n _g. Then, the condition for the antireflection film to prevent 100% of reflection of light and to transmit 100% of light already needs to satisfy the relations of the following formulas (1) and (2). Known (Science Library Physics = 9 "Optics" 70-7
(Page 2, 1980, published by Science Co., Ltd.).

[0006]

[Equation 1]

The refractive index of glass n _g = about 1.5 and M
Refractive index of gF ₂ film n ₀ = 1.38, wavelength of incident light λ ₀ =
Since it is already known to be 5500Å (reference), by substituting these values into the equation (2), it is calculated that the optimum thickness h of the antireflection film is about 0.1 μm.

[0008]

However, the method of applying the antireflection coating to the transparent substrate has a problem that the surface of the formed coating film is easily scratched, which causes a decrease in light transmittance. In addition, the method of forming an ultrathin film or a metal vapor deposition film on the surface of the transparent substrate has a thickness of 0.1 μm as calculated from the formula (2) as described above.
It was quite thin, and because of this, the scratch resistance was poor and it was easy to peel from the transparent substrate. Further, in the method of laminating the coating film of the ionizing radiation curable resin and the vapor deposition film, the continuous process is difficult, the productivity is not increased, and the cost is increased. Further, the method of forming a coating film having a low refractive index on the cured film of the ionizing radiation-curable resin, the resin on the surface of the first cured film has almost no reactive groups, and the adhesion of the low refractive index film is It was bad.

Further, the polarizing element has a drawback that its function as a polarizing element is deteriorated by moisture. A polarizing plate formed by laminating a conventional antireflection film on a polarizing element cannot sufficiently prevent the permeation of moisture, and thus has a disadvantage that the polarizing function is deteriorated.

Therefore, a first object of the present invention is that the cured coating film is hard, has scratch resistance, and has good light transmittance.
It is an object of the present invention to provide a scratch-resistant base material and a polarizing plate which are easy to manufacture and have good anti-reflection property with good adhesion between layers.

The second object of the present invention is that the polarizing element is excellent in moisture resistance, the cured coating film is hard and has scratch resistance.
Another object of the present invention is to provide a scratch-resistant base material and a polarizing plate which have good light transmittance, are easy to manufacture, have good adhesion between layers, and have antireflection properties.

[0012]

[Means for Solving the Problem] Achieving the first purpose
Invention for achieving the above-mentioned first object, the scratch-resistant substrate having antireflection properties of the present invention, on one side or both sides of the transparent substrate,
Forming a lower layer coating film comprising a resin composition containing an ionizing radiation curable resin, and ionizing radiation curing having a refractive index slightly lower than that of the ionizing radiation curable resin composition of the lower layer coating film on the lower layer coating film An upper coating film made of a mold resin composition is formed, and the upper coating film is made of an ionizing radiation curable resin composition containing a fluorine atom.

Another anti-scratch-resistant base material of the present invention which achieves the first object mentioned above comprises a resin composition containing an ionizing radiation curable resin on one or both sides of a transparent substrate. A lower layer coating film is formed, and an upper layer coating film composed of an ionizing radiation curable resin composition having a refractive index slightly lower than that of the ionizing radiation curable resin composition of the lower layer coating film is formed on the lower layer coating film. The lower coating film contains metal compound fine particles having a higher refractive index than the ionizing radiation-curable resin composition of the lower coating film.

The polarizing plate of the present invention for achieving the first object is one in which the scratch-resistant base material having the antireflection property is laminated on a polarizing element.

Invention for Achieving the Second Objective Since the polarizing element used in the present invention generally has a drawback that the polarizing element is deteriorated by moisture from the outside, a scratch-resistant substrate and / or a polarizing plate. It is necessary to protect the polarizing element from the invasion of water by providing a moisture-proof layer on it.

That is, the scratch-resistant base material having antireflection property of the present invention which achieves the second object mentioned above is transparent in the scratch-resistant base material having antireflection property of the first invention. A moisture-proof layer is provided between the substrate and the lower coating film.

Further, a polarizing plate of the present invention for achieving the second object has a polarizing element and the first or second object arranged on one surface of the polarizing element. Achieving a scratch-resistant base material, wherein at least one moisture-proof layer is formed and laminated between the scratch-resistant base material and the polarizing element, and on the exposed surface of the polarizing element.

Further, another polarizing plate of the present invention for achieving the second object is a polarizing element and either one of the first or the second, which is arranged on one surface of the polarizing element. A scratch-resistant substrate that achieves the purpose of, and a transparent substrate arranged on the other surface of the polarizing element, the scratch-resistant substrate, each layer of the arrangement comprising the polarizing element and the transparent substrate, and At least one moisture-proof layer is formed and laminated on the exposed surface of the transparent substrate.

[0019]

The present invention will be described in more detail below.

Significance of providing the lower coating film: As described above, in order to prevent the reflection of the coating film, the above formula (1) must be satisfied. By the way, when the upper layer coating film is provided on the transparent substrate without providing the lower layer coating film, the antireflection property means that the refractive index of the upper layer coating film is limited by the refractive index of the transparent substrate. And the range of selection of fine particles is narrowed. In other words, conversely, when a specific material is used for the upper coating film to form a scratch-resistant upper coating film, the range of selection of the material of the transparent substrate existing below it may be narrowed. become.

On the other hand, in the present invention, by providing the lower layer coating film between the transparent substrate and the upper layer coating film,
Since the antireflection property of the coating film has a relation of the refractive index between the upper coating film and the lower coating film according to the above formula (1), it is not affected by the material of the transparent substrate, and the upper coating film is the lower coating film. There is an advantage that the range of selection of the resin and the like can be widened by appropriately selecting the material used for.

Refractive index: According to the above equation (1), the reflection is 1
In order to prevent the occurrence of 00%, a material may be selected so that the refractive index of the upper coating film is approximately the square root of the refractive index of the lower coating film. Therefore, the refractive index of the upper coating film is preferably slightly lower than the refractive index of the lower coating film. For example, when triacetyl cellulose is used for the transparent substrate,
It is desirable that the transparent substrate has a refractive index of about 1.49, the lower coating film has a refractive index of 1.49 or more, and the upper coating film has a refractive index of less than 1.49.

Transparent substrate: The transparent substrate in the present invention includes a transparent glass plate, a transparent resin plate, a transparent resin sheet and a transparent resin film. As the transparent resin film, triacetyl cellulose film, diacetyl cellulose film, acetate butyrate cellulose film, polyether sulfone film, polyacrylic resin film, polyurethane resin film, polyester film, polycarbonate film, polysulfone film, polyether film , Trimethylpentene film, polyetherketone film, (meth) acrylonitrile film and the like can be used, but in particular, triacetylcellulose film and uniaxially stretched polyester film are excellent in transparency and are suitable because they have no optical anisotropy. Used.

Lower layer coating film: The resin forming the lower layer coating film is a resin which is cured mainly by ultraviolet rays or electron beams, that is, an ionizing radiation curable resin alone, or an ionizing radiation curable resin mixed with a thermoplastic resin. Those used are a mixture of an ionizing radiation curable resin and a thermosetting resin, and a solid-phase reaction type ionizing radiation curable resin.

Generally, the ionizing radiation-curable resin has a refractive index of about 1.5, which is about the same as that of glass, but TiO ₂ (refractive index:
2.3-2.7), Y ₂ O ₃ (refractive index: 1.87), L
a ₂ O ₃ (refractive index: 1.95), ZrO ₂ (refractive index:
2.05), Al ₂ O ₃ (refractive index: 1.63), or another metal compound may be added to the paint to adjust the refractive index of the lower coating film to raise the refractive index.

The amount of the fine particles of the metal compound added varies greatly depending on the refractive index of the resin used and the refractive index of the metal compound used. For example, usually 30 with respect to 100 parts by weight of resin.
It is about 70 parts by weight. In this case, if too many fine particles of the metal compound are added, the transparency and strength of the lower coating film decrease, and these points must be taken into consideration.

Ionizing radiation curable resin: The ionizing radiation curable resin used in the resins for forming the lower coating film preferably has an acrylate functional group, for example, a polyester having a relatively low molecular weight. Resins, polyether resins, acrylic resins, epoxy resins, urethane resins, alkyd resins, spiro acetal resins, polybutadiene resins, polythiol polyene resins, oligomers or prepolymers of (meth) acrylates of polyfunctional compounds such as polyhydric alcohols and reactions As a functional diluent, ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone, and other monofunctional monomers and polyfunctional monomers such as trimethylolpropane tri (meth) acrylate, hexanediol ( A) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neo Those containing a relatively large amount of pentyl glycol di (meth) acrylate can be used.

Further, in order to make the above-mentioned ionizing radiation curable resin composition into an ultraviolet curable resin composition, acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime are used as photopolymerization initiators therein. Ester, tetramethylthiuram monosulfide,
Thioxanthones and n-butylamine, triethylamine, tri-n-butylphosphine and the like can be mixed and used as a photosensitizer. Particularly in the present invention, it is preferable to mix urethane acrylate as the oligomer and dipentaerythritol hexaacrylate as the monomer.

Thermoplastic resin: As the thermoplastic resin mixed with the above-mentioned ionizing radiation-curable resin, any one can be used as long as it imparts viscosity to the ionizing radiation-curable resin, but in particular, the hardness of the coating film. In order to keep the temperature high, thermoplastic resins such as polymethylmethacrylate and polybutylmethacrylate can be preferably used. The purpose of mixing the thermoplastic resin with the ionizing radiation curable resin is to semi-cure the coating film when the ionizing radiation curable resin having a low refractive index of the lower coating film is applied, as described in detail later. . The mixing ratio of the thermoplastic resin to the ionizing radiation curable resin is 50 parts by weight or less with respect to 100 parts by weight of the ionizing radiation curable resin for the purpose of semi-curing the coating film.

Thermosetting resin: The thermosetting resin mixed with the above-mentioned ionizing radiation-curable resin includes phenol resin,
Urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, aminoalkyd resin, melamine / urea co-condensation resin, silicon resin, polysiloxane resin, etc. Then, a crosslinking agent, a curing agent such as a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier, an extender pigment, etc. are added as additives. As the curing agent, usually, isocyanate is an unsaturated polyester resin or polyurethane resin, and peroxide such as methyl ethyl ketone peroxide and a radical initiator such as azobisisobutyronitrile are often used for the unsaturated polyester resin. . Furthermore, as the isocyanate as the curing agent, divalent or higher valent aliphatic or aromatic isocyanate can be used.

Solid-phase reaction type ionizing radiation-curable resin: The above-mentioned solid-phase reaction type ionizing radiation-curable resin is solid at room temperature in an uncured state, and has thermoplasticity and solvent solubility. It is mainly composed of an ionizing radiation curable resin that gives a coating that is non-fluid (drying to the touch) even when touched by hand by coating and drying, and that is non-adhesive. is there. Specifically, for example, the following two types of resins (a) and (b) are exemplified. A similar resin is disclosed in JP-A-1-202492. Furthermore, the resins shown in (a) and (b) below can be mixed and used, and a radically polymerizable unsaturated monomer can be added thereto for use.
Reactive diluents, sensitizers and the like used in ordinary ionizing radiation curable resins are added to these resins. Further, a non-crosslinking thermoplastic resin may be added in order to impart flexibility to the cured resin product.

(A) A resin having a radically polymerizable unsaturated group in a polymer having a glass transition temperature of 0 to 250 ° C.

Specifically, it is a resin in which a radical copolymerizable unsaturated group is introduced by the methods (a) to (d) to be described below, which is obtained by polymerizing or copolymerizing the following monomers.

Monomers having hydroxyl groups: For example, N-methylol (meth) acrylamide, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy. Examples include propyl (meth) acrylate.

Monomers having a carboxyl group: For example,
Examples include (meth) acrylic acid and (meth) acryloyloxyethyl monosuccinate.

Monomers having an epoxy group: Examples include glycidyl (meth) acrylate.

Monomers having an aziridinyl group: 2-aziridinylethyl (meth) acrylate, allyl 2-aziridinylpropionate and the like.

Monomers having amino groups: (meth) acrylamide, diacetone (meth) acrylamide, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate and the like.

Monomers having sulfone groups: 2- (meth) acrylamido-2-methylpropanesulfonic acid and the like.

Monomer having isocyanate group: 2,4
-Addition products of a diisocyanate and a radical copolymer having active hydrogen, such as an addition product of 1 mol to 1 mol of toluene diisocyanate and 2-hydroxyethyl (meth) acrylate.

Furthermore, in order to control the glass transition temperature of the copolymer and the physical properties of the cured film, each of the monomers listed above and the following compounds can be copolymerized. Examples of such a copolymerizable monomer include methyl (meth) acrylate and propyl (meth).
Examples thereof include acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, gt-butyl (meth) acrylate, isoamyl (meth) acrylate, cyclohexyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate.

UV curing is carried out by polymerizing or copolymerizing the above-mentioned monomers by introducing radically polymerizable unsaturated groups by the following methods (a) to (d). Ionizing radiation curable resin such as mold resin or electron beam curable resin is obtained.

In the case of (a) a polymer or copolymer of a monomer having a hydroxyl group, a monomer having a carboxyl group such as (meth) acrylic acid is subjected to a condensation reaction.

(B) In the case of a polymer or copolymer of a monomer having a carboxyl group or a sulfone group, the above-mentioned monomer having a hydroxyl group is subjected to a condensation reaction.

(C) In the case of a polymer or copolymer of a monomer having an epoxy group, an isocyanate group or an aziridinyl group, the above-mentioned monomer having a hydroxyl group or a monomer having a carboxyl group is subjected to an addition reaction. Let

(D) In the case of a polymer or copolymer of a monomer having a hydroxyl group or a carboxyl group, a monomer having an epoxy group, a monomer having an aziridinyl group or a diisocyanate compound and a hydroxyl group-containing acrylic acid An addition reaction of 1 mol to 1 mol of the ester monomer is carried out.

In order to carry out the above reaction, it is desirable to add a trace amount of a polymerization inhibitor such as hydroquinone and to carry it out while sending dry air.

(B) A resin having a melting point of normal temperature (20 ° C.) to 250 ° C. and having a radical polymerizable unsaturated group.

Specific examples include stearyl acrylate, stearyl (meth) acrylate, triacryl isocyanate, cyclohexanediol (meth) acrylate, spiroglycol diacrylate and spiroglycol (meth) acrylate.

Upper layer coating: The resin used for the upper layer coating of the surface of the scratch-resistant substrate of the present invention having scratch resistance is the same as the ionizing radiation curable resin used for the lower layer coating. Although it can be used, in particular, in order to lower the refractive index than that of the lower coating film, for example, it is used for a glass fiber such as acrylate or methacrylate containing a fluorine atom having a refractive index of 1.35 to 1.41. Those that are present are preferable. For example, these resins include F-based macromonomers (F-20
925, Shin-Nakamura Chemical Co., Ltd., trifluoroethyl acrylate (biscoat 3F, Osaka Organic Chemicals), trifluoroethyl methacrylate (biscoat 3FM, Osaka Organic Chemicals), tetrafluoropropyl acrylate (biscoat 4F, Osaka Organic Chemicals), Tetrafluoropropyl methacrylate (Biscoat 4FM, made by Osaka Organic Chemical),
Octafluoropentyl acrylate (Biscoat 8F,
Osaka Organic Chemicals), octafluoropentyl methacrylate (Viscoat 8FM, Osaka Organic Chemicals), heptadecafluorodecyl acrylate (Viscoat 17F, Osaka Organic Chemicals), heptadecafluorodecyl methacrylate (Viscoat 17FM, Osaka Organic Chemicals) is there.

The above-mentioned resin for glass fiber has a low refractive index of 1.35 to 1.41, but it is necessary to adjust the refractive index of the upper coating film to a lower value in relation to the refractive index of the lower coating film. In some cases, fine particles such as SiO ₂ and MgF ₂ can be added to the coating material for forming the upper coating film to such an extent that the transparency can be maintained, and the refractive index of the coating film can be adjusted and lowered. The amount of fine particles of these metal compounds added is preferably 0.5 to 10
It is about 1 part by weight, particularly 1 to 5 parts by weight is suitable in consideration of transparency.

In addition to the above ionizing radiation curable resin for glass fiber, a usual ionizing radiation curable resin is used,
The refractive index of the coating film obtained by adding fine particles of a metal compound such as MgF ₂ can be adjusted. In this case, the ordinary ionizing radiation curable resin has a refractive index of about 1.
It is about 5 and higher than the refractive index of the above-mentioned ionizing radiation curable resin for glass fiber. Therefore, in order to lower the refractive index of the lower layer coating film, a large amount of fine particles of a metal compound for lowering the refractive index must be added to the ionizing radiation curable resin. For example, usually about 50 to 70 parts by weight of fine particles of a metal compound are added to 100 parts by weight of the resin. However, if too many fine particles of a metal compound are added, the transparency of the coating film and the strength of the coating film will decrease, so these points must be taken into consideration.

As described above, the ionizing radiation-curable resin is used as the coating material for forming the upper layer coating film, but in consideration of adhesion with the lower layer coating film, a solvent that attacks the lower layer coating film, such as methyl ethyl ketone or ethyl acetate. It is desirable to include such a solvent in the paint. The thickness of the upper coating film is 40
In order to favorably transmit light having a wavelength of 0 to 900 nm, 0.1 to 0.15 μm is desirable. The lower layer coating film and the upper layer coating film formed on the transparent substrate are preferably provided not only on one side of the transparent substrate but also on both sides.

Method for curing coating film: In the present invention, the lower coating film applied on a transparent substrate is dried by touch or half cured to form a semi-cured layer, and a scratch-resistant upper coating film is formed thereon. The coating material is applied and both coating films are cured at the same time. The reason why the lower layer coating film is semi-cured in advance when double-coating both coating films is that if the upper layer coating film-forming coating material is applied on the completely cured lower layer coating film to form a coating film, While adhesion is poor and defects such as peeling occur, if the lower coating film is semi-cured and the upper coating film-forming coating material is applied repeatedly, and then both coating films are completely cured, Because of the good adhesion.

In the present invention, semi-curing is classified as follows depending on the type of resin used. (1) Solvent drying type semi-curing a. Solvent-drying semi-curing Normal ionizing radiation-curing resin is applied with a solvent added, and the coating film formed by drying the solvent is in a semi-cured state, and the ionizing radiation-curing resin is a curing reaction. Is not completed.

Since the above composition alone cannot maintain a sufficient viscosity, a solvent-drying thermoplastic resin is added to adjust the viscosity suitable for coating. When a coating film is formed using this resin composition, the solvent is released and diffused during drying, and the coating film is in a semi-cured state.

As the solvent-drying type thermoplastic resin to be added to the ionizing radiation-curable resin, those which are usually used are used. Especially, when polymethyl methacrylate or polybutyl methacrylate is used, the hardness of the coating film is high. Can be kept. Moreover, in this case, since the refractive index is close to that of the main ionizing radiation curable resin, the transparency of the coating film is not impaired,
It is advantageous in transparency. As another example of the solvent-drying thermoplastic resin, when a cellulose-based polymer is added to an ionizing radiation-curable resin, when triacetyl cellulose is used as a transparent substrate, toluene, which is a non-soluble solvent of triacetyl cellulose, is used. Even if the transparent substrate is coated with the resin, the adhesion between the transparent substrate and the coating resin can be improved. Moreover, since toluene has a property of not dissolving triacetyl cellulose as a transparent substrate, it does not whiten the transparent substrate.

The mixing ratio of this resin composition is such that the addition amount of the thermoplastic resin is 50 parts by weight or less with respect to 100 parts by weight of the ionizing radiation curable resin. If the addition amount of the thermoplastic resin is more than this, the hardness of the upper coating film cannot be kept high,
Inferior scratch resistance.

B. Solid-state reaction type ionizing radiation curing type semi-curing This semi-curing is a state of semi-curing by the solid-state reaction type ionizing radiation-curing resin, which is solid at room temperature in the uncured state, and has thermoplasticity and solvent. It refers to a state in which the resin has solubility, is non-fluid and non-tacky by appearance and by touching with coating and drying, and the curing reaction of the ionizing radiation curable resin is not completed.

(2) Half cure type semi-curing a. Ionizing radiation curable resin semi-crosslinking type semi-curing Applying using the ordinary ionizing radiation curable resin shown in the section of the undercoat coating film, adjusting the irradiation conditions of ionizing radiation such as ultraviolet rays or electron beams to the coating film. It means a semi-cured state formed by carrying out semi-crosslinking.

B. Ionizing radiation curable resin / thermosetting resin blend type semi-curing Mixing a thermosetting resin with the ionizing radiation curable resin shown in the above section of the lower coating film, applying a resin composition, and applying heat to the coating film. It means a semi-cured state formed by the above.

The mixing ratio of this resin composition is such that the addition amount of the thermosetting resin is 50 parts by weight or less with respect to 100 parts by weight of the ionizing radiation curing resin. The reason is that if the amount of the thermosetting resin added is more than this, the hardness of the coating film decreases.

C. Solvent-drying / half-cure-type composite semi-curing It means a state in which the solvent-drying type semi-curing state of (1) above is further irradiated with ionizing radiation to be a semi-curing state. This semi-cured state is the same as the semi-cured state described in JP-A-1-20249.

Complete curing: Complete curing of both the lower coating film and the upper coating film in the present invention is carried out by irradiation with ionizing radiation. When the ionizing radiation curable resin composition is applied on the lower layer coating film, the lower layer coating film is in a semi-cured state, and the ionizing radiation curable resin component contained in the lower layer coating film is not completely cured. . Therefore, since the ionizing radiation curable resin in both the lower coating film and the upper coating film contains an uncured component, both coating films are simultaneously completely cured by irradiation with ionizing radiation.

Irradiation device: The ionizing radiation-curable resin composition used in the present invention can be cured by a usual method for curing an ionizing radiation-curable resin composition, that is, by irradiating with an electron beam or an ultraviolet ray. . For example, in the case of electron beam curing, Cockloft-Walton type, Van de Graaff type,
Emitted from various electron beam accelerators such as resonance transformer type, insulated core transformer type, linear type, dynamitron type, high frequency type, etc.
0 to 1000 KeV, preferably 100 to 300 KeV
In the case of ultraviolet curing, ultraviolet rays emitted from light rays such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, carbon arc, xenon arc, and a metal halide lamp can be used.

The present invention is not limited to the above description, and various modifications can be made based on the spirit of the present invention. For example, a coating film having antiglare property may be further formed on one side or both sides of the scratch resistant substrate having antireflection property of the present invention.

Scratch-Resistant Substrate Having a Moisture-Proof Layer and Polarizing Element: FIGS. 2, 3 and 4 show examples of the constitution of a scratch-resistant substrate having a moisture-proof property and an antireflection property. In FIG. 2, the moisture-proof layer 4 is formed on the transparent substrate 1, and the I.D. The scratch-resistant base material having the moisture-proof property and the anti-reflection property, in which the lower layer coating film 2 described in the above section is formed and the upper layer coating film 3 is further formed thereon, is shown. In FIG. 3, a moisture-proof layer 4 is formed on both upper and lower sides of a transparent substrate 1, a lower layer coating film 2 is formed on one moisture-proof layer 4, and an upper layer coating film 3 is further formed on the moisture-proof layer 4 to have moisture-proof property. Scratch resistant substrates are shown which have good anti-reflection properties. Further, in FIG. 4, the moisture-proof layer 4 is formed on one surface of the transparent substrate 1, the lower layer coating film 2 is formed on the other surface of the transparent substrate 1, and the upper layer coating film 3 is further formed thereon. A scratch resistant substrate having moisture resistance and antireflection properties is shown.

5, FIG. 6, FIG. 7, FIG. 8 and FIG. 9 show examples of the position where the moisture-proof layer is formed in the polarizing plate composed of the polarizing element and the scratch resistant base material and / or the transparent substrate. Figure 5
Polarized light in which the scratch-resistant base material 6 having the moisture-proof property and the anti-reflection property described above is arranged on one surface of the polarizing element 5, and the transparent substrate 11 is arranged on the other surface of the polarizing element 5. In the plate, the moisture-proof layer 14 is formed between the transparent substrate 11 and the polarizing element 5.

In FIG. 6, the scratch-resistant substrate 6 having the moisture-proof property and the antireflection property described above is arranged on one surface of the polarizing element 5, and the other surface of the polarizing element 5 is transparent. Board 1
In the polarizing plate on which 1 is arranged, the moisture-proof layer 14 is formed on the exposed surface side of the transparent substrate 11.

In FIG. 7, the scratch-resistant base material 6 having the moisture-proof property and the antireflection property described above is arranged on one surface of the polarizing element 5, and the other surface of the polarizing element 5 is transparent. Board 1
In the polarizing plate in which 1 is arranged, the moisture-proof layer 14 is formed between the transparent substrate 11 and the polarizing element 5 and on the exposed surface side of the transparent substrate 11.

In FIG. 8, the scratch-resistant base material 6 having the moisture-proof property and the antireflection property described above is arranged on one surface of the polarizing element 5, and the other surface of the polarizing element 5 is exposed. In the present polarizing plate, the moisture-proof layer 14 is formed between the polarizing element 5 and the scratch-resistant base material 6 and on the exposed surface of the polarizing element 5.

In FIG. 9, a scratch-resistant substrate 6 having a moisture-proof property and an antireflection property is arranged on one surface of the polarizing element 5, and a transparent substrate 11 is arranged on the other surface of the polarizing element 5. In the prepared polarizing plate, the position where at least one or more moisture-proof layers 14 can be formed is shown between any layers.

Materials for the moisture-proof layers 4 and 14 include polytetrafluoroethylene, fluorine resin, acrylic resin, silicon dioxide, indium oxide, tin oxide, titanium oxide, aluminum oxide, zirconium oxide, magnesium fluoride,
Zinc oxide or the like is used. As a method of forming the moisture-proof layer, a thin film forming method such as a plasma polymerization method, a vacuum vapor deposition method, a sputtering method, an ion plating method, or a thick film forming method is used. The scratch-resistant base material having the moisture-proof layer of the present invention can be produced by using a transparent substrate having the moisture-proof layer in advance.

[0074]

Example 1 An electron beam curable resin (EX containing a mixture of polyester acrylate and polyurethane acrylate)
A coating composition was prepared by adding 50 parts by weight of polymethacrylic acid methacrylate as a thermoplastic resin to 100 parts by weight of G: trade name: manufactured by Dainichiseika. A polyester film (HP-
7: Product name: Teijin) surface thickness of 10 μm (when dry)
Was applied so that Octafluoropentyl methacrylate (Viscoat 8FM: Osaka Organic Chemical)
Was coated with a methyl ethyl ketone to form a coating film for the upper layer, which was applied by a gravure reverse coating method so as to have a film thickness of 0.12 μm (when dried). The coating film was dried to remove the solvent, and the electron beam accelerated at 175 KeV was irradiated with 5 Mra.
By irradiating with the energy of d, the upper layer coating film and the lower layer coating film were completely cured simultaneously.

The above treatment was also applied to the back surface of the polyester film to form the same lower layer coating film and upper layer coating film on both sides of the transparent substrate. The obtained anti-scratch base material having antireflection property is shown in FIG. 1 is a transparent substrate made of polyester film, 2 is a lower layer coating having a refractive index of 1.54, and 3 is a refractive index of 1.3.
8 is the upper layer coating film. The anti-scratch base material having antireflection property obtained in Example 1 had a transmittance of about 5% and a decrease in reflection with light having a wavelength of 350 to 700 nm.

[0076]

[Example 2] As the lower layer coating material, 100 parts by weight of the lower layer coating material used in Example 1 and 30 parts by weight of ZnO ₂ particles were added. The lower coating film paint 1 used in the above Example 1
The same treatment as in Example 1 was carried out except that 50 parts by weight of MgF ₂ particles was added to 00 parts by weight to obtain a scratch-resistant substrate having antireflection properties. The obtained scratch-resistant base material having antireflection property has a wavelength of 350 to 700 n.
With light of m, the transmittance increased by about 7% and the reflection decreased.

[0077]

Example 3 F which is a triacetyl cellulose film
A polytetrafluoroethylene thin film was formed on T-UV-80 (trade name: manufactured by Fuji Photo Film Co., Ltd.) by plasma polymerization. A lower coating film and an upper coating film were formed on the side opposite to the thin film forming surface by the method described in Example 1 above to obtain a scratch-resistant base material having moisture resistance and antireflection property. .

On the other hand, a polytetrafluoroethylene thin film was formed on the triacetyl cellulose film by plasma polymerization in the same manner as described above to obtain a transparent substrate on which a moisture-proof layer was formed.

Separately, a polarizing element made of a polyvinyl alcohol film was prepared, and the polarizing element was prepared by using the scratch-resistant base material having the moisture-proof and anti-reflection properties and the transparent substrate having the moisture-proof layer formed thereon. A polarizing plate having moisture resistance and scratch resistance was obtained by laminating the respective moistureproof layers on the inner side.

[0080]

According to the present invention, it is possible to obtain a scratch-resistant substrate having an antireflection property, which has a good light transmittance, is easy to manufacture, has a layer structure with good adhesion.

Further, according to the present invention, the light transmittance is good,
It is possible to obtain a scratch-resistant base material that is easy to manufacture, has a layer structure with good adhesion, and has moisture resistance and antireflection properties.

[Brief description of drawings]

FIG. 1 shows a cross section of a scratch-resistant substrate having antireflection properties of the present invention.

FIG. 2 shows a cross section of a scratch-resistant base material on which a moisture-proof layer of the present invention is formed.

FIG. 3 shows a cross section of another scratch-resistant substrate provided with the moisture-proof layer of the present invention.

FIG. 4 shows a cross section of yet another scratch-resistant substrate provided with the moisture-proof layer of the present invention.

FIG. 5 shows a cross section of a polarizing plate on which a moisture-proof layer of the present invention is formed.

FIG. 6 shows a cross section of another polarizing plate on which the moisture-proof layer of the present invention is formed.

FIG. 7 shows a cross section of still another polarizing plate on which the moisture-proof layer of the present invention is formed.

FIG. 8 shows a cross section of still another polarizing plate on which the moisture-proof layer of the present invention is formed.

FIG. 9 shows positions where a moisture-proof layer can be formed in the polarizing plate of the present invention.

[Explanation of symbols]

1,11 transparent substrate 2 Lower layer coating 3 Upper layer coating film 4,14 Moisture barrier 5 Polarizing element 6 Scratch resistant substrate

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 2H049 BA02 BB33 BB43 BB46 BB63                 2K009 AA02 AA15 BB02 BB14 BB28                       CC03 CC09 CC24 CC34 DD02                       DD05                 4F100 AB01B AK01B AK01C AK25C                       AR00A AR00D BA03 BA04                       BA05 BA07 BA10A BA10C                       BA26 DE01B EH46B GB90                       JB14B JB14C JD04D JK12                       JN01A JN01B JN06 JN18C                       JN30E

Claims (10)

[Claims] 1. A lower coating film comprising a resin composition containing an ionizing radiation curable resin is formed on one surface or both surfaces of a transparent substrate, and the ionizing radiation curable resin composition of the lower coating film is formed on the lower coating film. An upper layer coating film formed of an ionizing radiation curable resin composition having a refractive index slightly lower than the refractive index, wherein the upper layer coating film is composed of an ionizing radiation curable resin composition containing a fluorine atom. A scratch-resistant base material having anti-reflection property. 2. An underlayer coating comprising a resin composition containing an ionizing radiation-curable resin is formed on one or both sides of a transparent substrate, and the ionizing radiation-curable resin composition for the underlayer is coated on the underlayer coating. The upper coating film is formed of an ionizing radiation curable resin composition having a refractive index slightly lower than the refractive index, and the lower coating film has a higher refractive index than the ionizing radiation curable resin composition of the lower coating film. A scratch-resistant substrate having antireflection properties, which comprises fine metal compound fine particles. 3. The scratch-resistant substrate having antireflection properties according to claim 1, wherein the ionizing radiation-curable resin composition containing a fluorine atom is an acrylate or a methacrylate containing a fluorine atom. . 4. The antireflection property according to claim 1 or 3, wherein the lower layer coating contains fine particles of a metal compound having a higher refractive index than the ionizing radiation-curable resin composition of the lower layer coating. A scratch resistant base material having. 5. A moisture-proof layer is provided between the transparent substrate and the lower layer coating film, according to any one of claims 1 to 4.
A scratch-resistant substrate having the antireflection property according to the item. 6. The upper layer coating film contains fine particles of a metal compound having a refractive index lower than that of the ionizing radiation-curable resin composition of the upper layer coating film.
A scratch-resistant substrate having the antireflection property according to the item. 7. The antireflection property according to claim 1, wherein a coating film having an antiglare property is further formed on one surface or both surfaces of the scratch resistant substrate. A scratch resistant base material having. 8. A polarizing plate comprising the scratch resistant substrate according to claim 1 laminated on a polarizing element. 9. (1) A polarizing element, comprising the scratch-resistant base material according to any one of claims 1 to 7 disposed on one surface of the polarizing element, and (2) the scratch-resistant material. A polarizing plate, characterized in that at least one moisture-proof layer is formed and laminated on the interlayer of the organic base material and the polarizing element and on the exposed surface of the polarizing element. 10. (1) A polarizing element, the scratch-resistant base material according to claim 1 disposed on one surface of the polarizing element, and the other surface of the polarizing element. And (2) at least one moisture-proof layer is formed on each of the layers of the scratch resistant substrate, the polarizing element and the transparent substrate, and on the exposed surface of the transparent substrate. A polarizing plate characterized by being laminated.