JPH11183710A - Antidazzle hard coating film and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antidazzle hard coating film having a fine rugged structure on the surface, a good antidazzle effect and surface characteristics with excellent scratching resistance and hard coating property, and to provided its producing method. SOLUTION: This hard coating film has an active energy ray-hardening resin coating film on one surface of a transparent plastic base material 1. The surface of the active energy ray-hardening resin coating film has a rough structure 3, 4 comprising two kinds of fine ruggedness patterns with different height of projections. The two kinds of fine ruggedness patterns consists of a part with 0.1 to 0.2 μm average difference in height and a part with 2.1 to 10 μm average difference in height.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to various display devices,
Especially LCD, CRT, PDP, ECD, ELD, FE
The present invention relates to an antiglare hard coat film suitable for being provided on a screen of a display device represented by D or a light emitting diode display device. The “film” used in the hard-coated antiglare film of the present invention means a film-like film and a sheet-like film, and any of these cases.

[0002]

2. Description of the Related Art In the above-mentioned various displays such as LCDs and CRTs, there is a disadvantage that light is incident on the screen from the outside, and this light is reflected on the surface of the screen, making it difficult to view the displayed image. In particular, in recent years, with the rapid spread and large size of flat panel displays, solving the above-mentioned drawbacks (hereinafter referred to as anti-glare) has become an increasingly important issue. In particular, since the liquid crystal display does not emit light by itself, and unless a backlight is built in, an image must be displayed using external light. Hitherto, as a means for imparting anti-glare properties, anti-glare layers composed of films or sheets having an uneven surface structure by various methods such as sandblasting, embossing, and blending of inorganic and organic fine particles have been proposed. And
In order to not only give the appearance of fine texture and eliminate the feeling of roughness when touched, but also to prevent the glare caused by the high definition of the display, a finer uneven structure on the surface (hereinafter referred to as a fine uneven structure) ) Is increasing.

[0003] However, if the uneven structure formed on the surface of the antiglare hard coat film is a substantially uniform fine structure, all the convex portions that come into contact during the frictional action and the scratching action are damaged, Scratches are conspicuous, and scratch resistance and surface hardness deteriorate. In other words, the abrasion resistance and surface without reducing the effects of the appearance of fine texture and the feeling of roughness when touched obtained by the formation of the fine uneven structure, and the prevention of glare due to the high definition of the display. Improvements in hard coat properties such as hardness are required.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems required for a film or sheet, and has a fine uneven structure on the surface and exhibits a good antiglare effect. It is an object of the present invention to provide an antiglare hard coat film having surface properties excellent in abrasion resistance and also having a hard coat property, and a method for producing the same.

[0005]

Means for Solving the Problems The means provided by the present invention for solving the above problems is the invention shown in claim 1, wherein at least one surface of a transparent plastic base material is provided with an active energy ray-curable type. A resin coating layer is provided,
An antiglare hard coat film, characterized in that a surface on the side of the active energy ray-curable resin coating layer is provided with a concavo-convex structure composed of two types of fine concavities and convexities having different height differences.

According to this, a hard coat film in which an active energy ray-curable resin coating layer is provided on at least one surface of a transparent plastic film or a sheet substrate, is provided on the surface of the hard coat film (or sheet). In addition, a fine uneven structure and an uneven structure having a relatively large difference in height from the fine uneven structure are provided for the purpose of improving damage to a friction action and a scratching action. In other words, the formation of the large uneven structure having a large difference in height, the effect of reducing the contact area on the surface of the hard coat film at the time of a friction action or a scratch action, imparts a hard coat property having abrasion resistance and excellent surface hardness. ing. Thus, the surface of the hard coat film contains two types of uneven structures having different height differences between peaks and valleys, and thus has both a fine uneven structure on the surface and a hard coat property having scratch resistance and excellent surface hardness. It has become possible to provide an antiglare hard coat film or sheet. In addition, as the active energy rays, ultraviolet rays, electron beams, radiation, visible light,
Alternatively, any other so-called electromagnetic wave in a broad sense may be used as long as it has an effect of giving activity (promoting a chemical reaction) to the material. However, in the field of application of the present invention, comprehensive evaluation of the performance and ease of handling required for the anti-glare hard coat film provided on the screen of the display device, cost, practicality, etc., ultraviolet rays are most suitable, Next, the order of electron beams.

[0007] More preferably, the invention is described in claim 2 and is an antiglare hard coat film based on the structure of claim 1, and in particular, the two types of fine irregularities are:
A portion where the average height difference of the fine irregularities is 0.1 to 2.0 μm,
It is characterized in that the average height difference of the irregularities is in the range of 2.1 to 10 μm.

Here, if the average height difference of the former is 0.1 μm
If it is less than m, it is not preferable because light incident from the outside is not sufficiently scattered. Also, if the former height difference is 2.
If the thickness exceeds 0 μm, the appearance of the fine texture will appear,
Effects such as elimination of a feeling of roughness when touched and prevention of a feeling of glaring are not sufficiently obtained, which is also undesirable. In the case of the latter, if the height difference is less than 2.1 μm, the effect of reducing the contact area of the hard coat film surface at the time of frictional action and scratching action is reduced, and the influence of friction and scratching is obtained. Is not preferred. Incidentally, suppose that 2.
If it is less than 0 μm, the distinction between the former and the latter is lost, and the constitution of the present invention itself is not achieved, and the average height difference itself is too small as a whole, and the effect of friction resistance and scratch resistance is lost. As a result, there is a problem that the entire surface is easily damaged. If the height difference of the former exceeds 10 μm, the surface roughness is unfavorable because the appearance roughness and the feeling of roughness when touched are excessive and unsuitable for use on a screen of a display device.

[0009] More preferably, the invention is described in claim 3 and is an antiglare hard coat film based on any one of claims 1 and 2, wherein the average height difference is particularly 0.1 to 1.0. The number of all the convex portions in the 2.0 μm portion occupies 60 to 95% of the number of all the convex portions of the fine uneven structure on the surface of the hard-coated antiglare film.

If it is less than 60%, the effects of the fine textured structure, such as the appearance of fine texture, the elimination of roughness when touched, and the prevention of glare can be sufficiently achieved. On the other hand, if it exceeds 95%, on the other hand, the effect of reducing the contact area on the surface of the hard coat film at the time of frictional action or scratching action is reduced, and the effect of friction or scratching is preferred. Absent.

According to a fourth aspect of the present invention, there is provided an anti-glare hard coat film based on the constitution of the first aspect, wherein the two types of fine irregularities include a portion having a small average height difference and an average It refers to a portion where the height difference is large, and is characterized in that the difference between the average height difference is 0.1 to 10.0 μm.

Here, when the difference between the average heights is less than 0.1, the difference between the average heights is carried by the larger portion.
The effect of reducing the contact area on the hard coat film surface during friction and scratching action is reduced, and the surface substrate and the former will be affected by friction and scratching, and the initial purpose may not be achieved There is. In addition, if tentatively 0.0
μm, there is no distinction between the former and the latter, the configuration of the present invention itself is not formed, the average height difference itself is too small as a whole, the effect of friction resistance and scratch resistance is lost As a result, there is a problem that the entire surface is easily damaged. If the height difference of the former is more than 10 μm, it is not preferable because the surface roughness and the feeling of roughness when touched are excessive and unsuitable for use on the screen of a display device.

More preferably, as set forth in claim 5,
An antiglare hard coat film based on any one of claims 1 and 4, wherein the number of all convex portions in the portion having a small height difference is a fine uneven structure on the surface of the antiglare hard coat film. Occupies 60 to 95% of the total number of the convex portions.

If the ratio is less than 60%, the effects of the appearance of fine texture, the elimination of roughness when touched, and the prevention of glare can be sufficiently achieved by the fine uneven structure. On the other hand, if it exceeds 95%, on the other hand, the effect of reducing the contact area on the surface of the hard coat film at the time of frictional action or scratching action is reduced, and the effect of friction or scratching is preferred. Absent.

According to a sixth aspect of the present invention, at least one surface of a substrate made of transparent plastic is coated with fine particles having approximately two kinds of particle diameters and an active energy ray-curable resin at least using these as components. The active energy ray-curable resin film layer is cured by irradiating the applied surface with an active energy ray thereafter, or the active energy ray curing is performed on at least one surface of a transparent plastic substrate. Applying a mold resin, irradiating the active energy ray-curable resin coating layer with an active energy ray to cure the active energy ray-curable resin coating layer, and then performing at least one of sandblasting and embossing. And an uneven structure composed of two types of fine unevenness having different average height differences of the unevenness according to any of the above. It is a manufacturing method of the antiglare hard coat film and providing a and cured active energy ray-curable resin coating layer provided on the surface on the substrate.

As the fine particles having approximately two kinds of particle sizes, inorganic or organic fine particles can be suitably used. A known coating technique can be suitably used when forming a coating layer by applying a liquid obtained by coating an active energy ray-curable resin (in some cases, dispersing the fine particles). Known techniques can also be applied to the sandblasting method. In this case, for example, at least two types of fine particles having different particle sizes are prepared as processing fine particles, and used in different processes. At this time, by changing the processing time and the blowing strength, fine irregularities having two kinds of the average height difference are formed. Known techniques can be applied to the embossing method.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
First, an antiglare hard coat film (or sheet)
Then, the method for producing the antiglare hard coat film (or sheet) will be described in order.

<Constituent Materials of Anti-Glare Hard Coat Film> FIG. 1 shows an outline of the anti-glare hard coat film according to the present invention. The material of the transparent plastic film or sheet as the substrate 1 is not particularly limited,
A known transparent plastic film or sheet having appropriate mechanical rigidity can be appropriately selected and used. Specific examples include polyester, polyethylene,
Polypropylene, cellophane, triacetyl cellulose, diacetyl cellulose, acetyl cellulose butyrate, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene vinyl alcohol, polystyrene, polycarbonate, polymethylpentene, polysulfone, polyetherketone, acrylic, nylon, Fluororesin, polyimide, polyetherimide, polyethersulfone and the like can be mentioned,
In the present invention, triacetylcellulose films and uniaxially stretched polyesters are presently preferred because of their excellent transparency and no optical anisotropy.

The active energy ray-curable resin for forming the hard coat layer 2 is not particularly limited, and any active energy ray may be used as long as it gives a coating film having a pencil hardness of H or more by ultraviolet or electron beam curing. can do. As such an ultraviolet curable resin, for example, a polyfunctional acrylate resin such as acrylic acid or methacrylic acid ester of polyhydric alcohol, diisocyanate, polyhydric alcohol and hydroxy ester of acrylic acid or methacrylic acid are synthesized. And polyfunctional urethane acrylate resins.
In addition to these, polyether resins having an acrylate-based functional group, polyester resins, epoxy resins,
An alkyd resin, a spiro acetal resin, a polybutadiene resin, a polythiol polyene resin, and the like can also be suitably used as needed.

The reaction diluents for these resins include relatively low-viscosity 1,6-hexanediol di (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, and hexane. Bifunctional or higher functional monomers and oligomers such as diol (meth) acrylate, pentaerythritol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, neopentyl glycol di (meth) acrylate, and the like; Monofunctional monomers, for example, acrylates such as N-vinylpyrrolidone, ethyl acrylate and propyl acrylate, ethyl methacrylate, propyl methacrylate,
Isopropyl methacrylate, butyl methacrylate,
Derivatives such as methacrylates such as hexyl methacrylate, isooctyl methacrylate, 2-hydroxyethyl methacrylate, cyclohexyl methacrylate, nonylphenyl methacrylate, tetrahydrofurfuryl methacrylate, and modified caprolactone thereof, styrene, α-methylstyrene, acrylic acid, etc. And mixtures thereof, and the like.

In the present invention, when the active energy ray is ultraviolet light, it is necessary to add a photosensitizer (radical polymerization initiator), and benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether Benzoin and its alkyl ethers, such as benzylmethyl ketal and acetophenone;
Acetophenones such as 2-dimethoxy-2-phenylacetophenone and 1-hydroxycyclohexylphenyl ketone; anthraquinones such as methylanthraquinone, 2-ethylanthraquinone and 2-aminoanthraquinone; thioxanthone, 2,4-diethylthioxanthone and 2,4- Thioxanthones such as diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone and 4,4-bismethylaminobenzophenone; and azo compounds. These can be used alone or as a mixture of two or more. Further, tertiary amines such as triethanolamine and metadiethanolamine; benzoic acid derivatives such as 2-dimethylaminoethylbenzoic acid and ethyl 4-dimethylaminobenzoate; It can be used in combination with a photoinitiating aid or the like. The amount of the organic peroxide or the photopolymerization initiator used is 0.5 to 20 parts by weight based on 100 parts by weight of the polymerization component of the resin composition.
Preferably it is 1 to 15 parts by weight.

The fine uneven structure 3 and the uneven structure 4 on the surface of the hard coat film can be formed by various methods such as, for example, sandblasting, embossing, or adjusting the blend of inorganic or organic fine particles. As the inorganic or organic fine particles, any fine particles that maintain good transparency in the active energy ray-curable resin can be used.

In general, fine particles made of silica, alumina, titania, zirconia, etc. are used as the inorganic fine particles. Among them, silica particles, especially synthetic silica, are preferred from the viewpoints of anti-glare properties, resolution and hard coat properties. Particles are preferred. Both regular and amorphous silica can be used.
In addition, conductive transparent fine particles such as tin oxide, indium oxide, cadmium oxide, and antimony oxide can be used irrespective of imparting chargeability.

As the organic fine particles, hard fine particles having an appropriate crosslinked structure inside the particles and free from swelling due to active energy ray-curable resins, monomers, solvents and the like can be used. For example, styrene-based resin of particle internal cross-linking type, styrene-acrylic copolymer resin, acrylic resin, divinylbenzene resin, silicone resin,
Urethane resins, melamine resins, styrene-isoprene resins, benzoguanamine resins, and other reactive microgels can be used. The blending amount of the transparent fine particles is
0.5 to 20 parts by weight of active energy ray-curable resin
Parts by weight, preferably 1 to 15 parts by weight.

If necessary, known general paint additives can be blended. For example, a silicone-based or fluorine-based additive that imparts leveling, surface slip properties, etc. is effective in preventing scratches on the surface of the cured film, and when ultraviolet rays are used as active energy rays, the above-described additives are used. By bleeding to the air interface, the inhibition of curing of the resin due to oxygen can be reduced, and an effective curing degree can be obtained even under low irradiation intensity conditions.
The addition amount of these is suitably 0.01 to 0.5 part based on 100 parts by weight of the active energy ray-curable resin.

<Manufacturing Method of Anti-Glare Hard Coat Film> The coating method of the hard coat layer is optional, but in the production stage, a roll coater, a reverse roll coater, a gravure coater, a knife coater, a bar coater and the like are generally used. It is a target.

When an ultraviolet ray is used as the active energy ray source, a light source such as a high-pressure mercury lamp, a low-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, a carbon arc or a xenon arc can be used. A metal halide lamp is generally used when a filler is contained or a thick film is cured.

In the case of using an electron beam for curing, a Cockloft-Wald type, a Bande-Craft type, a resonance transformer type,
50 to 1000 emitted from various electron beam accelerators such as insulated core transformer type, linear type, dynamitron type and high frequency type
An electron beam having an energy of keV, preferably 100 to 300 keV can be used.

The antiglare hard coat film of the present invention comprises:
It has a structure composed of the transparent plastic substrate and the hard coat layer. The resin of the hard coat layer is blended with a required amount of two or more inorganic or organic fine particles having different particle diameters by a known dispersion method such as a disperser mixer or a sand mill, and the cured film thickness is preferably 0.5 μm or more. Is applied so as to have a thickness of 10 μm or less, and then cured by irradiation with active energy rays.

[0030]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples. All parts and percentages are based on weight unless otherwise specified.

<Hard coat layer> An electron beam-curable coating composition having the following formulation was prepared by the following procedure. First, a mixed solvent of toluene / 2-butanone = 1/1 is changed in a mixing weight ratio of silica particles having an average particle size of 2.0 μm and a particle size of 5.0 μm, and high-speed stirring is performed by a disper mixer to obtain a silica dispersion. Was adjusted.
Next, the above silica dispersion was gradually added to a mixed solution of a hexafunctional urethane acrylate oligomer and trimethylolpropane triacrylate while stirring, thereby preparing the mixture.

Hexafunctional urethane acrylate oligomer 40 parts (trade name: U-6HA, manufactured by Shin-Nakamura Chemical Co., Ltd.) Trimethylolpropane triacrylate 60 parts (manufactured by Toagosei Co., Ltd.) Toluene 50 parts 2-butanone 50 parts Silica 5 Part (trade name: Mizuperl, S-200, particle size 2.0 μm, and trade name: Mizuperl, S-500, particle size 5.0 μm. All manufactured by Mizusawa Chemical Industries)

Next, on one side of the 80 μm-thick triacetyl cellulose film, the above-mentioned electron beam-curable coating composition was applied using a wire bar, and the solvent was evaporated to form a coating layer having a thickness of about 2.5 μm. After formation, a hard coat layer was prepared by subjecting an electron beam having an acceleration voltage of 200 keV from the coating film side to a curing treatment under the conditions of an absorbed dose of 3 Mrad.

<Evaluation Method> For the obtained antiglare hard coat film, the average height difference of the irregularities on the surface of the hard coat film formed of silica of each particle diameter was expressed by S
After measuring the ratio of the number of protrusions on the surface by EM observation and three-dimensional surface roughness measurement, various physical properties were evaluated by the following measurement methods. Surface roughness: Measured by a surface roughness and contour measurement system of Surfcom 550AD (manufactured by Tokyo Seimitsu Co., Ltd.). Pencil hardness: Pencils having different hardnesses were used to determine the presence or absence of scratches under a load of 500 g. Abrasion resistance: The surface of the hard coat film was rubbed 10 times with a # 0000 steel wool while applying a load of 400 g, and the occurrence of scratches and the degree of scratches were visually observed.

<Evaluation Results> Among the irregularities on the surface of the hard coat layer, the average height difference of the fine irregularity structure made of silica having a particle size of 2.0 μm is 0.7 μm, and the height difference of the irregularity structure having a particle size of 5.0 μm. Was 3.4 μm. Table 1 shows the ratio of the number of convex portions formed of silica having each particle size and the results of evaluating various physical properties by the above-described measurement methods.

[0036]

[Table 1]

From the above, by setting the weight mixing ratio of each silica having an average particle size of 2.0 μm and an average particle size of 5.0 μm to 8: 2, only silica particles having an average particle size of 2.0 μm were mixed. It can be seen that although the surface roughness (Ra value) hardly changes, the scratch resistance is improved and the pencil hardness is also improved.

[0038]

As is clear from the above description of the embodiment, a hard coat film having an active energy ray-curable resin coating layer provided on at least one surface of the transparent plastic substrate according to the present invention, An anti-glare film that has two types of uneven structures with different peaks and valleys in the hard coat film or sheet to combine the fine uneven structure on the surface with the abrasion resistance and the hard coat property with excellent surface hardness. A hard coat film or sheet was provided. In particular, when used on the display surface, the fine uneven structure not only gives the appearance of fine texture and eliminates the roughness when touched,
It enables the prevention of glare due to the high definition of the display, and the inclusion of a concavo-convex structure with a larger difference in height reduces frictional effects and reduces the area of contact with the hard coat layer surface during use, resulting in scratch resistance. It is also possible to provide a hard coat property having excellent properties and excellent surface hardness.

In general, according to the present invention, an anti-glare hard disk having a fine uneven structure on its surface, exhibiting a good anti-glare effect, having excellent surface characteristics with excellent scratch resistance, and also having a hard coat property. A coated film and a method for producing the same can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a layer structure of an antiglare hard coat film or sheet of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base material 2 ... Hard coat layer 3 ... Fine unevenness structure 4 ... Unevenness structure

Claims (6)

[Claims] 1. An active energy ray-curable resin coating layer is provided on at least one surface of a substrate made of a transparent plastic, and the surface on the side of the active energy ray-curable resin coating layer has a different level of unevenness. An antiglare hard coat film having an uneven structure composed of two types of fine unevenness. 2. The two kinds of fine unevenness include a part having an average height difference of 0.1 to 2.0 μm and a part having an average height difference of 2.1 to 10 μm. The antiglare hard coat film according to claim 1, wherein: 3. The number of all projections in the portion where the average height difference is 0.1 to 2.0 μm is 60 to 95 of the number of all projections in the fine uneven structure on the surface of the antiglare hard coat film. %. 3. The anti-glare hard coat film according to claim 1, wherein the hard coat film occupies a% of the film. 4. The two types of fine irregularities refer to a portion having a small average height difference and a portion having a large average height difference,
The hard-coated antiglare film according to claim 1, wherein the difference between the average heights is 0.1 to 10 μm. 5. The method according to claim 1, wherein the number of all convex portions in the portion where the height difference is small is
The antiglare hard coat film according to claim 1, wherein the antiglare hard coat film occupies 60 to 95% of the total number of convex portions having a fine uneven structure on the surface of the antiglare hard coat film. 6. A method in which at least one surface of a base material made of a transparent plastic is coated with fine particles having approximately two kinds of particle diameters and an active energy ray-curable resin which has been converted into a liquid by using at least these components. Irradiating the application surface with active energy rays to cure the active energy ray-curable resin coating layer, or applying the active energy ray-curable resin to at least one surface of a transparent plastic substrate, After the active energy ray-curable resin film layer is cured by irradiating the energy ray-curable resin film layer with an active energy ray, at least one of sandblasting or embossing is performed. 2 with different average height differences
A method for producing an antiglare hard coat film, comprising: providing an uneven structure composed of various kinds of fine unevenness on the surface and providing a cured active energy ray-curable resin coating layer on a substrate.