JP2015067682A - Hard coat film, plastic substrate, composition for forming hard coat film, and touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hard coat film that is excellent in hard coat property and antiblocking property and has a refractive index adjusted to suppress visibility of an electrode pattern, a plastic substrate including the hard coat film, a composition for forming a hard coat film from which a hard coat film having an adjusted refractive index can be formed, and a touch panel.SOLUTION: The hard coat film has an arithmetic average roughness Ra of a surface of 3 nm or more and 6 nm or less, 300 or more and 1000 or less projections having an average height or more per 400 μmsurface on the surface thereof, and a refractive index of 1.52 or more.

Description

  The present invention relates to a hard coat film, a plastic substrate, a composition for forming a hard coat film, and a touch panel.

Plastic base materials are transparent and lightweight, and are used in many applications such as packaging and optics, including the home appliance industry and the automobile industry.
A plastic substrate is often used as a substitute for glass. However, since a plastic substrate is more easily damaged than glass, a hard coat film for preventing damage is generally formed on the surface.

  On the other hand, since the surface of a plastic substrate (hereinafter simply referred to as “plastic substrate”) on which a hard coat film is formed is smooth, the hard coat film surfaces of the plastic substrate are overlapped with each other for a long time. In such a case, a “blocking phenomenon” may occur in which they are in close contact with each other and cannot be easily peeled off.

  Therefore, when a blocking phenomenon occurs in the manufacturing process, it may cause a decrease in productivity and a product defect. In addition, even after production, when the hard coat surfaces of the plastic substrate come into contact with each other and a blocking phenomenon occurs, it is difficult to separate the plastic substrates and the plastic substrate may not be usable. there were.

  In order to solve the above problem, a film coated with a composition containing a polyfunctional polymerizable monomer and organic fine particles having an average primary particle size of 80 nm to 500 nm has been proposed (see Patent Document 1). According to Patent Document 1, since convex portions due to organic fine particles are formed on the film surface, a hard coat film in which blocking is suppressed can be obtained.

  By the way, the plastic substrate is also used as a transparent conductive substrate for a liquid crystal display screen. An example of such a transparent conductive substrate is a substrate in which a patterned ITO (tin-containing indium oxide) electrode is provided on a plastic substrate provided with a hard coat layer.

  However, in such a transparent conductive substrate, since the refractive index of the hard coat layer is relatively lower than the refractive index of the ITO electrode, the portion where the ITO electrode is present and the portion where the ITO electrode is not present (the portion where the refractive index is high and the portion where the refractive index is low) The boundary part becomes clear. As a result, when the transparent conductive substrate is incorporated in the liquid crystal display screen, a phenomenon called “bone visible phenomenon” in which the ITO electrode can be seen occurs, and the visibility of the liquid crystal display screen is lowered. .

  In order to solve the above problem, a plastic substrate is proposed in which an intermediate refractive index layer having a refractive index of 1.65 or more and 1.85 or less is provided between a hard coat film and an ITO electrode (see Patent Document 2). ). This plastic base material can reduce the bone appearance phenomenon by providing an intermediate refractive index layer such as alumina.

JP 2009-256577 A JP-A-08-240800

  As described above, the bone appearance phenomenon is caused by a difference in refractive index between a structure of a material having a high refractive index such as an ITO electrode and a layer on which the structure is laminated. Therefore, the bone visibility phenomenon is suppressed by appropriately adjusting the refractive index of the layer in which such structures are stacked, and eliminating the difference in refractive index with the structure and utilizing the interference of reflected light and scattered light. To be considered.

  In Patent Document 2 described above, a hard coat film having anti-blocking properties as in Patent Document 1 is formed in order to obtain a plastic substrate that is excellent in hard coat properties and anti-blocking properties and can suppress the bone appearance phenomenon. An ITO electrode was patterned on the surface opposite to the surface, and a film having a high refractive index was coated thereon.

  However, when a multilayer film having such a structure is used, the number of manufacturing processes increases, and light scattering is likely to occur due to the presence of inorganic particles in the high refractive index film and organic fine particles in the hard coat film. Become. Therefore, if the content of highly bent particles is increased in order to obtain a desired high refractive index, it is necessary to reduce the content of organic fine particles in order to suppress light scattering, and sufficient antiblocking properties cannot be obtained. There was a problem.

  For these reasons, there has been a demand for a hard coat film having hard coat properties and anti-blocking properties, and having a refractive index adjusted to suppress the bone appearance phenomenon.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a hard coat film that is excellent in hard coat properties and anti-blocking properties, and further has an adjusted refractive index for suppressing a bone appearance phenomenon. And Another object of the present invention is to provide a plastic substrate provided with the hard coat film, a hard coat film forming composition capable of forming a hard coat film with an adjusted refractive index, and a touch panel.

That is, according to one embodiment of the present invention, the arithmetic average roughness Ra of the surface is 3 nm or more and 6 nm or less, and the number of convex portions having a height equal to or higher than the average height on the surface is 300 per 400 μm ^{2 of the} surface. A hard coat film having 1000 or less and a refractive index of 1.52 or more is provided.

In one embodiment of the present invention, a hard coat film having a haze value of 1.5% or less may be used.
In one embodiment of the present invention, a hard coat film having an average diameter of the convex portions in a plan view of 600 nm or less may be used.

  One embodiment of the present invention provides a plastic substrate having a substrate body formed using a resin material and the hard coat film of the present invention provided on at least one surface of the substrate body.

  One embodiment of the present invention includes a first particle having a volume-based median diameter (D50) of 5 nm to 120 nm, a second particle having a volume-based median diameter (D50) of 500 nm to 2000 nm, and curing. A hard coat film-forming composition comprising metal oxide particles having a refractive index of 1.9 or more.

  In one embodiment of the present invention, the content ratio of particles having a volume-based particle diameter of 150 nm or more and 300 nm or less, assuming that 100% by volume of all particles included in the entire range for measuring the volume-based particle diameter is 100% by volume. May be 0 vol% or more and 30 vol% or less, and the content ratio of particles having a volume-based particle size exceeding 3000 nm may be 0 vol% or more and 5 vol% or less. .

  One embodiment of the present invention provides a touch panel including at least one of the hard coat film of the present invention and the plastic substrate of the present invention.

  According to the present invention, in addition to hard coat properties, a hard coat film that is excellent in anti-blocking properties and has a refractive index adjusted to 1.52 or more can be provided as a single layer. Moreover, the plastic base material provided with this hard coat film, the composition for hard coat film formation which can form this hard coat film, and a touch panel can be provided.

6 is a diagram showing an AFM image of a hard coat film of Example 3. FIG. 6 is a diagram showing an AFM image of a hard coat film of Comparative Example 1. FIG.

Hereinafter, the form for implementing the hard-coat film | membrane of this invention, the plastic base material provided with the same, the composition for hard-coat film formation, and a touchscreen is demonstrated.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

[Hard coat film]
In the hard coat film of the present embodiment, the arithmetic average roughness Ra of the surface is 3 nm or more and 6 nm or less, and the number of convex portions having a height of the average height or more on the surface is 300 per 400 μm ^{2 of the} surface. The refractive index is 1.52 or more.
The hard coat film of this embodiment preferably has a haze value of 1.5% or less.
The heart coat film of this embodiment preferably contains inorganic particles having a refractive index of 1.9 or more.
As the inorganic particles having a refractive index of 1.9 or more, metal oxide particles having a refractive index of 1.9 or more of a “hard coat film forming composition” described later can be suitably used.

  In this embodiment, the “hard coat film” refers to a film having a pencil hardness of 2H or more when measured with a 750 gf load based on JIS-K-5600-5-4.

In this embodiment, “arithmetic average roughness Ra” refers to the arithmetic average roughness Ra defined in JIS-B0601-2013. Hereinafter, it may be simply referred to as “surface roughness Ra”.
In the present embodiment, specifically, a value obtained by scanning the range of 20 μm × 20 μm with an atomic force microscope (AFM) (SII, SPA300 / SPI3700) and calculating the surface roughness Ra. This is referred to as “arithmetic mean roughness Ra”.

In the present embodiment, the “average height” refers to the “average height of the roughness curve” used when calculating the “arithmetic average roughness Ra” in JIS-B0601-2013, and is the most of the roughness curve. It refers to the average value of heights calculated based on the low point.
In the present embodiment, specifically, the value calculated by scanning an area of 20 μm × 20 μm with an atomic force microscope (AFM) (S300, SPA300 / SPI3700) is calculated as “average”. "Height".

In the present embodiment, the “number of convex portions” refers to a value obtained by scanning a range of 20 μm × 20 μm with an atomic force microscope (AFM) (SPII, SPA300 / SPI3700).
The "surface 400 [mu] m ² per" is that "400 [mu] m per ² in the plan view area of the hard coat film", not that of the surface area along the unevenness of the surface of the hard coat film.

  In the present embodiment, the “refractive index of the hard coat film” is obtained by measuring the reflection spectrum in the visible light region with a spectrophotometer, and using the following formula (bottom reflectance) based on the lowest reflectance (bottom reflectance): The value calculated using 1). The upper limit of the refractive index is practically about 2.0.

(R ₀ ; bottom reflectance, n ₁ ; refractive index of air, n ₂ ; refractive index of hard coat film, n ₃ ; refractive index of substrate)

In the present embodiment, the “haze value” refers to the ratio (%) of diffuse transmitted light to total light transmitted light, using a haze meter NDH-2000 (manufactured by Nippon Denshoku Co., Ltd.) based on air. It means a value measured based on the industrial standard JIS-K-7136.
Specifically, the hard coat film is measured by measuring the haze value of the base material to which the hard coat film is attached as a blank and taking the difference from the haze value of the test piece having the hard coat film attached to the base material. Only the haze value can be measured.

  When the surface roughness Ra of the hard coat film is 3 nm or more, the convex portions are present on the surface to the extent that good antiblocking properties are obtained. Further, when the surface roughness Ra of the hard coat film is 6 nm or less, the haze value of the hard coat film is lowered, and good transparency of the hard coat film is obtained. Further, for example, when the films provided with the hard coat film are stacked, the film is prevented from being damaged by the convex portion.

On the surface of the hard coat film, if the number of protrusions having a height equal to or higher than the average height is 300 or more per 400 μm ² , the protrusions exist at substantially all locations on the surface of the hard coat film. As a result, good antiblocking properties can be obtained. Further, when the number of convex portions having a height equal to or higher than the average height is 1000 or less per 400 μm ² , good transparency can be obtained.

On the surface of the hard coat film, the number of protrusions having a height equal to or higher than the average height is preferably 500 or more and 900 or less per 400 μm ² , more preferably 600 or more and 900 or less, more preferably 700 or more and 900 or less is more preferable.

The refractive index of the hard coat film of this embodiment is adjusted to 1.52 or more. Here, the reason why the refractive index of the hard coat film is set to 1.52 or more is that at least a refractive index equal to or higher than that of the plastic substrate used as the substrate is necessary to suppress the bone appearance phenomenon. .
Moreover, it is preferable that the refractive index of the hard coat film of this embodiment is 1.52 or more, and is equivalent to the refractive index of a base material. By matching the refractive indexes of the base material and the hard coat film, interference unevenness due to the difference in the refractive index between the base material and the hard coat film is suppressed, and a film with better visibility can be obtained.

  By setting the refractive index of the hard coat film to 1.52 or more, it is possible to suppress a bone appearance phenomenon when a structure having a higher refractive index than that of the hard coat film is laminated. For example, when a patterned ITO electrode is provided on a plastic substrate provided with a hard coat layer, the difference in refractive index between the hard coat layer and the ITO electrode is reduced, and the bone appearance phenomenon is suppressed.

When the ITO electrode is directly provided on the hard coat film, the refractive index of the hard coat film is preferably 1.57 or more in order to reduce the refractive index of the hard coat film and the ITO electrode. More preferably, it is more preferably 1.62 or more.
In addition, when a film having a refractive index lower than that of the hard coat film is provided between the hard coat film and the ITO electrode to suppress the bone appearance phenomenon, the refractive indexes of the hard coat film and the substrate are made substantially the same. Thus, it is possible to reduce interference unevenness due to a difference in refractive index between the base material and the hard coat film. In this case, the refractive index of the hard coat film may be appropriately adjusted according to the refractive index of the substrate to be used.
The upper limit of the refractive index is practically about 2.0.

  The haze value of the hard coat film is preferably 1.2% or less, and more preferably 1.0% or less.

  Further, for the convex portion having a height equal to or higher than the average height, the average diameter of the convex portion at the average height in plan view is preferably 100 nm or more and 600 nm or less, and preferably 300 nm or more and 600 nm or less. . When the convex portion having an average diameter in this range is present on the film surface, a hard coat film having good anti-blocking properties and good transparency can be obtained.

Here, the “average diameter of the convex portion” is obtained by calculating the diameter of the convex figure in a plan view at the height position of the average height for each convex portion, and averaging the obtained diameters of the respective convex portions. Value. The figure corresponds to the figure drawn when the convex part and the horizontal plane at the height position of the average height overlap.
In the present embodiment, specifically, a value calculated by scanning a range of 20 μm × 20 μm with an atomic force microscope (AFM) (SII, SPA300 / SPI3700) is calculated as “plane”. The average diameter of the convex portion in view ".

  The film thickness of the hard coat film of this embodiment may be appropriately adjusted according to the use, but is preferably 0.1 μm or more and 20 μm or less, and more preferably 1 μm or more and 10 μm or less. By setting the film thickness within the above range, a hard coat film having excellent hard coat properties, anti-blocking properties and transparency can be obtained.

Further, the scratch resistance of the hard coat film is evaluated by the number of scratches visually observed when # 0000 steel wool is slid 10 times under a load of 250 g / cm ² . As a result of evaluation, the hard coat film of the present embodiment preferably has zero scratches. In the present invention, the measurement result of the scratch resistance of the hard coat film can be used as an index of the hard coat property of the hard coat film together with the pencil hardness described above.

The height of the convex portion on the surface of the hard coat film is preferably 10 nm or more and 60 nm or less, more preferably 20 nm or more and 55 nm or less, and further preferably 30 nm or more and 55 nm or less.
Since the height of the convex portion on the surface of the hard coat film is within the above range, there is a convex portion on the surface so that good antiblocking properties can be obtained, and this convex portion is suppressed from damaging the back surface of the film. In addition, good transparency of the hard coat film can be obtained.
In addition, the reference height (0 nm) when measuring the height of a convex part points out the lowest point of a roughness curve.

It is preferable that the hard coat film of this embodiment slide smoothly when the hard coat film surfaces are rubbed together. When the hard coat film surfaces are pressed against each other, it is preferable to slide smoothly without feeling a catch.
Further, when the hard coat film and the plastic film of this embodiment are rubbed together, it is preferable that the plastic film slide smoothly without being damaged. When the hard coat film and the plastic film are pressed against each other, it is preferable that the plastic film does not get scratched and slides smoothly without feeling caught.

The hard coat film of this embodiment preferably has a total light transmittance of 88% or more and 100% or less, and more preferably 90% or more and 100% or less.
In the present embodiment, “total light transmittance” means a value measured based on Japanese Industrial Standard JIS-K-7136 using a haze meter NDH-2000 (manufactured by Nippon Denshoku) with air as a reference. .
Specifically, by measuring the total light transmittance of the substrate to which the hard coat film is attached as a blank, and taking the difference from the total light transmittance of the test piece to which the hard coat film is attached to this substrate, The total light transmittance of only the hard coat film can be measured.

The hard coat film of the present embodiment preferably has a surface resistance value of less than 1 × 10 ¹² Ω / □.
In this embodiment, the “surface resistance value” means a surface resistance value when a voltage of 500 V is applied using a resistivity meter (Hiresta IP, manufactured by Dia Instruments).

[Method for producing hard coat film]
The method for producing the hard coat film of the present embodiment is not particularly limited, for example, a step of coating the composition for forming a hard coat film of the present embodiment, which will be described later, on an object to be coated, and forming a coating film, And a step of curing the coating film.

  Examples of the coating method in the step of forming the coating film include bar coating, flow coating, dip coating, spin coating, roll coating, spray coating, meniscus coating, gravure coating, and suction coating. A normal wet coating method such as a construction method or a brush coating method can be used.

What is necessary is just to select suitably as the hardening method in the process of hardening a coating film according to the composition for hard-coat film formation to be used. For example, when a photocurable composition is used as the composition for forming a hard coat film, the coating film may be irradiated with energy rays and photocured. The energy rays used for photocuring are not particularly limited as long as the coating is cured. For example, energy rays such as ultraviolet rays, far-infrared rays, near-ultraviolet rays, infrared rays, X-rays, γ rays, electron beams, proton rays, and neutron rays are used. Can be used. Among these energy rays, curing by ultraviolet irradiation, which has a high curing rate and is easily available, is preferable.
By curing the coating film, a hard coat film excellent in antiblocking property and transparency can be obtained.

In case of UV curing, using a high-pressure mercury lamp which emits light in the wavelength band of 200 nm to 500 nm, a metal halide lamp, a xenon lamp, a chemical lamp or the ^like, irradiated with 100mJ / cm ² ~3,000mJ / cm 2 of energy And the like.

[Composition for forming hard coat film]
The composition for forming a hard coat film according to this embodiment includes a first particle having a volume-based median diameter (D50) of 5 nm to 120 nm and a volume-based median diameter (D50) of 500 nm to 2000 nm. 2 and a monomer of a curable resin, and the refractive index of the first particles is metal oxide particles of 1.9 or more.

  The composition for forming a hard coat film of the present embodiment further has a volume-based particle size of 150 nm or more and 300 nm or less when the total particle included in the entire range for measuring the volume-based particle size is 100% by volume. The content of the particles is preferably 0% by volume or more and 30% by volume or less, and the content of the particles having a volume-based particle size exceeding 3000 nm is preferably 0% by volume or more and 5% by volume or less.

Here, “volume-based median diameter (D50)” means that the particles to be measured are dispersed in an organic solvent such as methyl ethyl ketone, isopropyl alcohol, and toluene, and the resulting dispersion is subjected to a particle size distribution by a dynamic light scattering method. It can be determined by measuring.
In the following description, “volume-based median diameter (D50)” is referred to as “average dispersed particle diameter”.

(monomer)
The monomer of this embodiment is not particularly limited as long as it is a monomer of a curable resin used for a hard coat film, and a monomer of a photocurable resin may be used, or a monomer of a thermosetting resin may be used. .
From the viewpoint of obtaining a hard coat film having high transparency and strong hard coat properties, it is preferable to use a monomer of a photocurable resin, and among the monomers of the photocurable resin, one or more acryloyl groups are included in the molecule. And a crosslinkable compound having one or both of methacryloyl groups.

Although it does not specifically limit as a crosslinkable compound which has one or both of 1 or more acryloyl group and methacryloyl group in a molecule | numerator, The polyfunctional acrylate excellent in reactivity, transparency, a weather resistance, and hardness is desirable. Here, polyfunctional means having three or more functional groups. The term “three or more” may be the same or different functional groups.
Examples of functional groups other than acryloyl group and methacryloyl group include vinyl group, allyl group, allyl ether group, styryl group, and hydroxyl group.

  Specific examples of the polyfunctional acrylate include (meth) trimethylolpropane triacrylate, (meth) ditrimethylolpropane tetraacrylate, (meth) pentaerythritol triacrylate, (meth) pentaerythritol tetraacrylate, (meth) dipentaerythritol hexa Examples include polyol polyacrylates such as acrylates, epoxy (meth) acrylates, polyester (meth) acrylates, urethane acrylates, and polysiloxane acrylates. These polyfunctional acrylates may be used alone or in combination of two or more.

(First particle)
As the first particles of this embodiment, metal oxide particles having a refractive index of 1.9 or more and having an average dispersed particle diameter of 5 nm or more and 120 nm or less are used.
The average dispersed particle size is preferably 5 nm or more and 100 nm or less, and more preferably 10 nm or more and 50 nm or less.
Since the first particles having such a particle size range are present in the composition, a convex portion can be formed on the entire surface of the hard coat film without reducing the permeability of the hard coat film, and The refractive index of the hard coat film can be improved.

  The first particle is not particularly limited as long as it is a particle made of a metal oxide having a refractive index of 1.9 or more. Examples of such metal oxides include zirconium oxide, zinc oxide, iron oxide, copper oxide, titanium oxide, tin oxide, cerium oxide, tantalum oxide, niobium oxide, tungsten oxide, europium oxide, hafnium oxide, potassium titanate, Barium titanate, strontium titanate, potassium niobate, lithium niobate, calcium tungstate, antimony-containing tin oxide, tin-containing indium oxide and the like are preferably used. These may be used alone or in combination of two or more.

Among these metal oxides, zirconium oxide and titanium oxide are particularly preferable in terms of imparting a high refractive index.
Moreover, when providing electroconductivity to a hard-coat film | membrane, an antimony containing tin oxide and a tin containing indium oxide are used suitably.

Since the first particles have a sufficiently small average dispersed particle size than the wavelength of visible light, the loss of transmitted light due to light scattering can be suppressed. Therefore, even if particles having a high refractive index are used as the first particles, the influence of scattering due to the difference in refractive index between the resin and the particles is small, and the transparency of the hard coat film is hardly lowered. Therefore, the first particles have a wide degree of freedom of particle types that can be selected.
For example, when it is desired to improve the refractive index of the hard coat film, it is preferable to select zirconium oxide or titanium oxide having a high refractive index as the first particle, and when it is desired to impart conductivity to the hard coat film, The first particles are preferably selected from conductive particles such as ATO.

(Second particle)
As the second particles of the present embodiment, those having an average dispersed particle diameter of 500 nm or more and 2000 nm or less are used.
When the second particles having such a particle size range are present in the composition, good transparency can be obtained and the blocking phenomenon between the films can be suppressed. Moreover, when the films are overlapped, the film can be prevented from being damaged by the second particles.

The refractive index of the second particles is preferably appropriately selected from those close to the refractive index of the desired film, preferably 1.4 or more and 2.5 or less, and 1.5 or more and 2.5 or less. It is preferably 1.9 or more and 2.5 or less.
Such particles are made of silica, inorganic particles such as metal oxide particles having a refractive index of 1.9 or more like the first particles, and resin materials such as acrylic resin, polyacrylonitrile, polystyrene, and the like. Resin particles are preferably used. It is preferable to use metal oxide particles having a refractive index of 1.9 or more because a high refractive index film can be easily obtained.
These second particles may be used alone or in combination of two or more.

  As described above, in the hard coat film forming composition of the present embodiment, the first particles having an average dispersed particle diameter of 5 nm to 120 nm and the second particles having an average dispersed particle diameter of 500 nm to 2000 nm are used. Are going to mix. Hereinafter, the reason why the first particles and the second particles are mixed and used together will be described.

Conventionally, in order to impart anti-blocking properties to the hard coat film, it is preferable to form a convex portion on the surface of the hard coat film, and for this purpose, particles having a particle size of about 200 nm to 600 nm are mixed with the resin. It was.
However, when the amount of particles that can impart anti-blocking properties to the hard coat film is mixed, there is a problem in that the effect of scattering by the particles increases and the permeability of the hard coat film decreases.

In order to suppress the influence of particle scattering and to impart antiblocking properties to this problem, it is conceivable to reduce the amount of particles mixed into the resin and increase the particle diameter. However, in this case, the protrusion height of the protrusion formed on the surface of the hard coat film is increased. Therefore, the haze value of the hard coat film is lowered, and when the base materials on which the hard coat film is formed are overlapped with each other, the back surface of the base material is damaged by the convex portion, or the film is good when the base material is wound up. New problems have arisen, such as inconveniences such as being unable to wind, and feeling of being caught when the substrates are rubbed together.
For this reason, it has been difficult to achieve both transparency and anti-blocking properties with conventional hard coat films.

With respect to such a problem that the conventional hard coat film has, the present inventor has a small average dispersed particle size of 5 nm to 120 nm (first particle) for imparting antiblocking properties. And a composition for forming a hard coat film in which particles having a mean dispersed particle size of 500 nm or more and 2000 nm or less (second particles) capable of imparting anti-blocking properties are mixed, so that the anti-blocking properties are more than conventional. It has been found that a hard coat film having improved and improved transparency can be formed.
Furthermore, it has been found that if a metal oxide having a refractive index of 1.9 or more is used as the first particles, the refractive index of the hard coat film can also be improved.

  Details of the reason why the anti-blocking property is improved by combining particles having greatly different average dispersed particle diameters are unknown, but are estimated as follows.

  First, by mixing particles having a large average dispersed particle size and particles having a small average dispersed particle size, convex portions made of particles having a large average dispersed particle size and particles having a small average dispersed particle size are formed on the surface of the film. The

  Here, when there are only convex portions due to particles having a large average dispersed particle diameter, the surface portion of the film is flat except for the portions other than the convex portions, so that the blocking phenomenon is likely to occur, and sufficient anti-blocking occurs. I can't get sex.

  However, the presence of particles having a small average dispersed particle size results in the presence of convex portions due to particles having a small average dispersed particle size in places other than the convex portions due to particles having a large average dispersed particle size. As a result, there are almost no flat portions where there are no convex portions due to particles.

Therefore, the antiblocking property can be improved and the mixing amount of particles having a large particle diameter can be reduced. At the same time, the amount of particles having a large average dispersed particle size is reduced, so that the transparency can also be improved.
By using a metal oxide having a refractive index of 1.9 or more as the first particles, a decrease in the haze value of the film can be suppressed, and a high refractive index can be imparted to the hard coat film. A hard coat film excellent in anti-blocking property can be obtained as a single layer.

  Further, particles having a size greater than 150 nm and less than 300 nm are likely to scatter visible light. On the other hand, neither the first particles nor the second particles have an average dispersed particle size within the particle size range of the particles that are likely to cause light scattering, and it is difficult to reduce the transparency of the hard coat film.

  In the composition for forming a hard coat film of the present embodiment, the content of particles having a volume-based particle size of 150 nm or more and 300 nm or less is preferably 0% by volume or more and 30% by volume or less. Moreover, it is preferable that the content rate of the particle | grains on which a volume basis particle diameter exceeds 3000 nm is 0 volume% or more and 5 volume% or less.

  When the content ratio of particles having a volume-based particle size of 150 nm or more and 300 nm or less is in such a range, light scattering can be suitably suppressed and the transparency of the formed hard coat film can be ensured. In the composition for forming a hard coat film, the content of particles having an average dispersed particle diameter of 150 nm or more and 300 nm or less is preferably 25% by volume or less, and more preferably 15% by volume or less.

  Moreover, light scattering is suppressed as the content rate of the particle | grains on which a volume reference particle diameter exceeds 3000 nm is the said range, and transparency of the hard coat film formed can be ensured more. In the composition for forming a hard coat film, the content ratio of particles having a volume-based particle diameter exceeding 3000 nm is preferably 3% by volume or less, and more preferably 2% by volume or less.

  When manufacturing the above-mentioned hard coat film using the composition for forming a hard coat film of the present embodiment, the surface of the obtained hard coat film is changed by changing the mixing ratio of the first particles and the second particles. The arithmetic average roughness Ra, the number of convex portions having a height equal to or higher than the average height, and the average diameter of the convex portions can be controlled.

  Moreover, when manufacturing the above-mentioned hard coat film | membrane using the composition for hard-coat film | membrane formation of this embodiment, the monomer, the 1st particle | grains, the 1st particle | grain used, The refractive index of the hard coat film obtained can be adjusted by changing the refractive index of the second particles. The refractive index of the hard coat film can be obtained by proportionally allocating from the respective refractive indexes of the monomer, the first particle, and the second particle, and the mixing ratio thereof.

  Thus, in the composition for forming a hard coat film of the present embodiment, since the monomer and two types of particles (first particle and second particle) are included, the ratio between the monomer and the two types of particles is included. By changing the above, it is possible to easily obtain a hard coat film having a changed refractive index. Further, such a change in refractive index can be performed within a range that does not significantly affect the hard coat property and anti-blocking property of the hard coat film.

  In addition, since the hard coat film forming composition of this embodiment includes two types of particles, the hard coat film forming composition includes only one type of particle (the particle size distribution is one peak). Compared to the above, the degree of freedom in adjusting the anti-blocking property of the obtained hard coat film is high. That is, according to the composition for forming a hard coat film of the present embodiment, by changing the ratio of the two kinds of particles, the anti-hard coat film obtained can be obtained without changing the ratio of the monomer type and the monomer. The blocking property can be easily adjusted. Moreover, such a change in anti-blocking property can be performed within a range that does not significantly affect the refractive index and the hard coat property of the hard coat film.

  The mixing ratio of the first particles and the second particles may be appropriately adjusted in consideration of the desired anti-blocking property and transparency. However, the volume ratio (first particle) :( second particle) = It is preferable to mix so that it may become in the range of 90: 10-50: 50, 90: 10-70: 30 are more preferable, 90: 10-80: 20 are further more preferable.

When the mixing ratio of the second particles is increased, the Ra value is increased and the antiblocking property is improved. Further, when the mixing ratio of the second particles increases, it becomes difficult to form convex portions over the entire film surface, and the number of convex portions decreases. Furthermore, when the mixing ratio of the second particles increases, the haze value tends to increase, and the average diameter of the convex portion increases.
However, if the mixing ratio of the second particles becomes too high, the average diameter of the protrusions becomes too large, and it becomes impossible to suppress the scratching property and haze value on the back surface of the base material from increasing. It is preferable to mix 10 volume% or more.

When the mixing ratio of the first particles is increased, convex portions are easily formed over the entire film surface while suppressing an increase in the haze value, and the occurrence of a blocking phenomenon locally can be suppressed. Further, when the mixing ratio of the first particles increases, the Ra value decreases and the average diameter of the convex portion decreases.
However, if the mixing ratio of the first particles is too high, even if the blocking phenomenon can be suppressed, there is a problem that the substrate cannot be wound neatly when winding the substrate. It is preferable to mix by volume% or more.

The surfaces of the first particles and the second particles are modified with a surface treatment agent having an organic group that can improve the affinity with the resin obtained by polymerizing the above-described monomers. Is preferred. By modifying the surfaces of the first particles and the second particles with such a surface treatment agent, the adhesion between the particles and the resin can be increased, and the hard coat properties can be improved.
The surface treatment agent having an organic group is preferably an organosilicon compound, and a silane coupling agent, silicone oil, or the like is suitably used as the organosilicon compound.

Examples of the silane coupling agent include methyltrimethoxysilane, methyltriethoxysilane, phenyltriethoxysilane, methylmethoxysilane, n-propyltrimethoxysilane, n-propylmethyldimethoxysilane, n-propyltriethoxysilane, n Alkylsilane coupling agents such as -butyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane or the like Allylsilane coupling agent;
Vinylsilane coupling agents such as vinyltrimethoxysilane and vinyltriethoxysilane;
3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, etc., part of the alkyl group possessed by the above-mentioned alkylsilane coupling agent, or allyl group possessed by the allylsilane coupling agent An aminosilane coupling agent in which a part of is substituted with an amino group or a group having an amino group;
An acryloxysilane coupling agent obtained by substituting a part of the alkyl group of the above-mentioned alkylsilane coupling agent, such as 3-acryloxypropyltrimethoxysilane, or a part of the allyl group of the allylsilane coupling agent with an acryloxy group;
A methacryloxysilane coupling agent such as 3-methacryloxypropyltrimethoxysilane;
Part of the alkylalkyl group of the above-mentioned silane coupling agent, such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, or the like, or part of the allyl group of the allylsilane coupling agent was substituted with a mercapto group Mercaptosilane coupling agents; and the like.

Examples of the silicone oil include dimethyl silicone oil, methyl hydrogen silicone oil, epoxy-modified silicone oil, carboxyl-modified silicone oil, polyether-modified silicone oil, and amino-modified silicone oil.
Only 1 type may be used for the said silane coupling agent and silicone oil, and 2 or more types may be mixed and used for it.

  The mixing ratio of the first and second particles and the monomer can be appropriately adjusted in consideration of the anti-blocking property, transparency, and hard coat property of the obtained hard coat film. It is preferable that the mixture of the first particle and the second particle and the monomer are in a volume ratio (mixture of the first particle and the second particle) :( monomer) = 5: 95 to 30:70. .

When the mixing ratio of the first and second particles increases, the number of convex portions increases and good antiblocking properties can be obtained. Moreover, when the mixing ratio of the first and second particles increases, the haze value tends to increase. Further, the Ra value increases as the mixing ratio of the first and second particles increases. Furthermore, it is expected that the average diameter of the convex portion will increase.
However, if the mixing ratio of the first and second particles becomes too high, the haze value of the hard coat film becomes too high, and the hard coat component is reduced, so that the hard coat property becomes weak. Therefore, it is preferable to mix the monomer in an amount of 70% by volume or more.

When the mixing ratio of the monomer is increased, the haze value of the film is decreased and the hard coat component is increased, so that the hard coat property is improved. Further, the Ra value decreases as the monomer mixing ratio increases. Further, as the monomer mixing ratio increases, the number of convex portions decreases. Furthermore, it is expected that the average diameter of the convex portion is reduced.
However, if the monomer mixing ratio becomes too high, the anti-blocking property is lowered. Therefore, it is preferable to mix the first and second particles by 5% by volume or more.

  In the above composition, within a range that does not impair the effects of the invention, one or two functional groups, which are not included in the above-described monomers, oligomers, dispersants, polymerization initiators, antistatic agents, Refractive index modifier, antioxidant, UV absorber, light stabilizer, leveling agent, antifoaming agent, inorganic filler, coupling agent, preservative, plasticizer, flow regulator, thickener, pH adjuster In addition, various general additives such as a polymerization initiator may be appropriately contained. Here, “does not inhibit the effects of the invention” means, for example, the amount, particle size, color, etc. of various additives as appropriate in order to ensure the transparency of the hard coat film produced using the above composition. An operation that selects.

  Examples of the dispersant include anionic surfactants such as sulfate esters, carboxylic acids, and polycarboxylic acids, cationic surfactants such as quaternary salts of higher aliphatic amines, and higher fatty acid polyethylene glycol esters. Nonionic surfactants, silicon surfactants, fluorine surfactants, polymer surfactants having an amide ester bond, and the like can be mentioned.

  A polymerization initiator is suitably selected according to the kind of monomer to be used. In the case of using a photocurable resin monomer, a photopolymerization initiator may be used. What is necessary is just to select suitably the kind and quantity of a photoinitiator according to the monomer of the photocurable resin to be used. For example, known photopolymerization initiators such as benzophenone, diketone, acetophenone, benzoin, thioxanthone, quinone, benzyldimethyl ketal, alkylphenone, acylphosphine oxide, phenylphosphine oxide, etc. are used. be able to.

Since the composition for forming a hard coat film of the present embodiment is applied to a substrate to form a coating film, the viscosity is 2 mPa · s or more and 500 mPa · s or less in order to facilitate coating. It is preferably 0.5 mPa · s or more and 200 mPa · s or less.
Since the viscosity of the composition for forming a hard coat film is 0.2 mPa · s or more, it is preferable because the film thickness when formed into a coating film does not become too thin and the film thickness can be easily controlled. On the other hand, since the viscosity is 500 mPa · s or less, the viscosity is not too high, and the handling of the composition during coating is facilitated, which is preferable.

The viscosity of the hard coat film forming composition is preferably adjusted to the above range by appropriately adding an organic solvent to the hard coat film forming composition.
The organic solvent is not particularly limited as long as it is compatible with the composition for forming a hard coat film, and examples thereof include aliphatic hydrocarbons such as hexane, heptane and cyclohexane, and aromatic carbonization such as toluene and xylene. Hydrogens, alcohols such as methanol, ethanol and propanol, halogenated hydrocarbons such as methylene chloride and ethylene chloride, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, 2-pentanone and isophorone, ethyl acetate and butyl acetate Esters, cellosolves such as ethyl cellosolve, ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether, amide solvents, and ether ester solvents. These solvents may be used alone or in combination of two or more.

[Method for producing composition for forming hard coat film]
As a manufacturing method of the composition for hard-coat film formation of this embodiment, the method of mixing each material mentioned above as a component of the composition for hard-coat film formation can be mentioned mechanically.
Examples of the mixing device include a stirrer, a self-revolving mixer, a homogenizer, and an ultrasonic homogenizer.

The first particles and the second particles may be directly mixed with the monomer as they are, but it is preferable that the first particle and the second particle are previously dispersed in an organic solvent and then mixed with the monomer.
A commercially available dispersion liquid in which the first particles and the second particles are dispersed in a dispersion medium may be used.

The first particles and the second particles may be dispersed separately or simultaneously. For example, when the first particle and the second particle use the same particle as a raw material and constitute two kinds of particles having different dispersed particle sizes due to different dispersion states of the raw material particles, An aggregate of particles having a larger average particle size than the first particles and the second particles can be used as a starting material.
The average aggregate particle diameter of the starting material aggregate is preferably 800 nm or more and 3000 nm or less, more preferably 900 nm or more and 2500 nm or less, and further preferably 1000 nm or more and 2000 nm or less.
The starting material aggregate is preferably an aggregate of particles having an average primary particle diameter of 1 nm or more and 100 nm or less.
The “average agglomerated particle diameter” refers to a value obtained by measuring, for example, 100 or more, preferably 500 or more, the major axis of each aggregate with a scanning electron microscope, and calculating the average of the results.

  In this case, the starting material may be dispersed and pulverized, and the first particle and the second particle may be obtained by one dispersion by appropriately adjusting the stress, time, and the like during dispersion. In the particles obtained by such a method, the particles obtained by pulverizing the starting material are included as the first particles and the second particles. The obtained particles may be ground to raw material particles, or may be aggregates smaller than the starting raw material.

If the dispersion time is too long, the aggregates are all crushed and become the first particles. Therefore, when the stress during dispersion is strong, the dispersion time may be shortened as appropriate.
In this case, compared with the case where the particles are dispersed separately, the dispersion step can be reduced once, which is preferable in terms of the production step.

[Plastic substrate]
The plastic substrate of the present embodiment has a substrate body formed using a resin material and the above-described hard coat film provided on at least one surface of the substrate body.

  The plastic substrate is formed by coating the hard coat film forming composition of the present embodiment on the substrate body using a known coating method, and then curing the coating film. Can be obtained.

The substrate body is not particularly limited as long as it is a plastic substrate. Polyethylene terephthalate, triacetyl cellulose, acrylic resin, methyl methacrylate-styrene copolymer (MS resin), acrylonitrile-styrene copolymer (AS resin) , Acrylonitrile-butadiene-styrene copolymer (ABS resin), polystyrene, polyethylene, polypropylene, polycarbonate, vinyl chloride resin, cycloolefin polymer (COP) and the like can be used.
The refractive index of the substrate is preferably 1.52 or more and 1.70 or less.

The substrate body may be in the form of a sheet or film, but is preferably in the form of a film.
The plastic substrate of the present embodiment preferably has a haze value of 2.0 or less, more preferably 1.5 or less, and 1.0 or less when measured on the basis of air. Further preferred.

The plastic substrate of the present embodiment preferably slips smoothly when the hard coat film surfaces are rubbed together. When the hard coat film surfaces are pressed against each other, it is preferable to slide smoothly without feeling a catch.
In addition, when the hard coat film of the present embodiment and the substrate main body are rubbed together, it is preferable that the substrate main body slide smoothly without being damaged. Further, when the hard coat film and the substrate main body are pressed against each other, it is preferable that the substrate main body does not get damaged and slips smoothly without feeling caught.

[Touch panel]
The touch panel of this embodiment includes at least one of the hard coat film of this embodiment and the plastic substrate of this embodiment. Either one of the hard coat film and the plastic substrate may be provided, or both may be provided.

A method of providing one or both of the hard coat film of the present embodiment and the plastic substrate of the present embodiment on the touch panel is not particularly limited, and may be mounted by a known method. For example, the structure etc. which laminated | stacked the transparent conductive film by which the ITO electrode was patterned in order on the surface in which the hard-coat film was formed in the plastic base material of this embodiment, the alignment film, and the liquid crystal layer are mentioned. Between the hard coat layer and the ITO electrode, a high bending layer having a refractive index higher than that of the hard coating layer may be provided, a low bending layer may be provided, or both may be provided. With these configurations, the refractive index may be adjusted to improve the index matching between the hard coat layer and the ITO electrode.
Further, the antiblocking property may be improved by providing a hardcoat film having an antiblocking property on the surface opposite to the surface on which the hardcoat film of the present embodiment is formed.

  As described above, according to the hard coat film of the present embodiment, it is possible to obtain a hard coat film that is excellent in anti-blocking property and has a refractive index of 1.52 or more in addition to hard coat properties.

When the haze value of the hard coat film is 1.5% or less, a hard coat film having more excellent transparency can be obtained.
When the total light transmittance of the hard coat film is 88% or more and 100% or less, a hard coat film having more excellent transparency can be obtained.
When the average diameter of the projections on the surface of the hard coat film in a plan view is 600 nm or less, a hard coat film having further excellent transparency can be obtained.

  According to the plastic substrate of the present embodiment, since the hard coat film of the present embodiment is provided on at least one surface of the substrate body formed using a resin material, it is excellent in hard coat properties and anti-blocking properties, A plastic substrate having a refractive index of 1.52 or more on the hard coat surface side can be obtained.

According to the composition for forming a hard coat film of the present embodiment, a hard coat film having excellent hard coat properties and anti-blocking properties and a refractive index of 1.52 or more can be formed.
When particles having a refractive index of 1.9 or more are used as the second particles, a film having a higher refractive index can be obtained.
When a conductive metal oxide is used for one or both of the first particles and the second particles, a film having excellent antistatic performance can be obtained.

The composition for forming a hard coat film of the present embodiment is excellent in transparency when the content ratio of particles having a volume-based particle size of 150 nm or more and 300 nm or less is 0% by volume or more and 30% by volume or less. Can be obtained.
The composition for forming a hard coat film of the present embodiment has excellent transparency when the content ratio of particles having a volume-based particle size exceeding 3000 nm is 0% by volume or more and 5% by volume or less. A film in which scratches on the back surface of the material are suppressed can be obtained.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these Examples.

The particle diameters of the particles in the dispersions described in the following examples and comparative examples (dispersion particle diameter) are all values based on volume.
Further, in the following Examples and Comparative Examples, the average dispersion particle size of the particles is obtained by measuring the dispersion containing each particle with a particle size distribution meter (Microtrac UPA150 (manufactured by Nikkiso Co., Ltd.) based on the dynamic light scattering method). The value of the median diameter (D50) obtained by measuring in ()) was adopted.

[Production Example 1]
[Preparation of dispersion containing first particles]
40 g of zirconia particles having an average primary particle diameter of 15 nm and a refractive index of 2.1, 54 g of methyl isobutyl ketone, and 6 g of vinyltrimethoxysilane were mixed. This mixed solution was dispersed with a homogenizer to prepare a dispersion containing the first particles.
As a result of measuring the obtained dispersion with a particle size distribution meter, the average dispersed particle size of the contained particles is 30 nm, the content of particles of 150 nm or more and 300 nm or less is 0% by volume, and the content of particles exceeding 3000 nm The rate was 0% by volume.

[Production Example 2]
[Preparation of dispersion containing particles having a refractive index of less than 1.9]
20 g of silica particles having an average primary particle diameter of 10 nm and a refractive index of 1.45, 80 g of methyl ethyl ketone, and 3 g of vinyltrimethoxysilane as a surface treatment agent were mixed. This mixed solution was dispersed with a homogenizer to prepare a dispersion containing particles having a refractive index of less than 1.9.
As a result of measuring the obtained dispersion with a particle size distribution meter, the average dispersed particle size of the contained particles is 20 nm, the content of particles of 150 nm or more and 300 nm or less is 0% by volume, and the content of particles exceeding 3000 nm The rate was 0% by volume.

[Production Example 3]
[Preparation of dispersion containing second particles]
30 g of acrylonitrile particles having an average primary particle diameter of 150 nm and a refractive index of 1.53, 70 g of methyl isobutyl ketone, and 3 g of a phosphoric ester dispersant were mixed. This mixed solution was dispersed with a homogenizer to prepare a dispersion containing second particles.
As a result of measuring the obtained dispersion with a particle size distribution meter, the average dispersed particle size of the contained particles is 550 nm, the content of particles of 150 nm or more and 300 nm or less is 0% by volume, and the content of particles exceeding 3000 nm The rate was 0% by volume.

[Production Example 4]
[Preparation of dispersion containing second particles]
30 g of zirconia particles having an average primary particle diameter of 35 nm and a refractive index of 2.1, 80 g of methyl isobutyl ketone, and 4.5 g of vinyltrimethoxysilane were mixed. This mixed solution was dispersed with a homogenizer to prepare a dispersion containing the first particles.
As a result of measuring the obtained dispersion with a particle size distribution analyzer, the average dispersed particle size of the contained particles is 560 nm, the content of particles of 150 nm or more and 300 nm or less is 4.3% by volume, and particles exceeding 3000 nm The content of was 0% by volume.

[Production Example 5]
[Preparation of dispersion containing second particles]
20 g of silica particles having an average primary particle diameter of 250 nm and a refractive index of 1.45, 80 g of methyl ethyl ketone, and 3 g of vinyltrimethoxysilane were mixed. This mixed solution was dispersed with a homogenizer to prepare a dispersion containing second particles.
As a result of measuring the obtained dispersion with a particle size distribution meter, the average dispersed particle size of the contained particles is 560 nm, the content of particles of 150 nm or more and 300 nm or less is 26.5% by volume, and the particles exceed 3000 nm. The content of was 0% by volume.

[Example 1]
Each substance was mixed with the following mixing | blending, and the composition 1 for hard-coat film formation of Example 1 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 45.0% by mass
Dispersion liquid of Production Example 3 containing second particles: 5.2% by mass
Monomer: Dipentaerythritol hexaacrylate 9.6% by mass
Photopolymerization initiator: 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one 0.9% by mass
Solvent 1: Methyl ethyl ketone 31.4% by mass
Solvent 2: diacetone alcohol 7.9% by mass

  When all the particles in the hard coat film forming composition 1 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. It was.

[Hard coat film formation]
The obtained composition 1 for forming a hard coat film was applied to a 100 μm thick polyethylene terephthalate film by a bar coating method so that the dry film thickness would be 3 μm to 5 μm, dried by heating at 80 ° C. Formed.
Next, using a high pressure mercury lamp (120 W / cm), the coating film is exposed to UV light so as to have an energy of 300 mJ / cm ² and cured, whereby the hard coat film of Example 1 and the plastic substrate provided with the same Got.

[Example 2]
In the following Examples and Comparative Examples, the monomer, photopolymerization initiator, solvent 1 and solvent 2 were the same as those in Example 1, and only the blending amount was changed.

Each substance was mixed with the following mixing | blendings and the composition 2 for hard-coat film formation of Example 2 was obtained.
First particle: Methyl ethyl ketone dispersion (ATO content 20% by mass) containing antimony-containing tin oxide (ATO) having an average dispersed particle size of 40 nm and a refractive index of 2.0 60.0% by mass
Dispersion liquid of Production Example 3 containing second particles: 5.2% by mass
Monomer: 15.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 14.6% by mass
Solvent 2: 3.7% by mass

  When all the particles in the hard coat film forming composition 2 are taken as 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. It was.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 2 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 2 was used. Got.

[Example 3]
Each substance was mixed with the following mixing | blending, and the composition 3 for hard-coat film formation of Example 3 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 45.0% by mass
Dispersion liquid of Production Example 4 containing second particles: 5.7% by mass
Monomer: 9.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 31.0% by mass
Solvent 2: 7.8% by mass

  When all the particles in the hard coat film forming composition 3 are taken as 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0.5% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 3 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 3 was used. Got.

[Example 4]
Each substance was mixed by the following mixing | blendings and the composition 4 for hard-coat film formation of Example 4 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 52.5% by mass
Dispersion liquid of Production Example 4 containing second particles: 5.7% by mass
Monomer: 6.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 27.4% by mass
Solvent 2: 6.9% by mass

  When all the particles in the hard coat film forming composition 4 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0.4% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 4 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 4 was used. Got.

[Example 5]
Each substance was mixed with the following mixing | blending, and the composition 5 for hard-coat film formation of Example 5 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 22.5% by mass
Dispersion liquid of Production Example 4 containing second particles: 5.7% by mass
Monomer: 18.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 41.8% by mass
Solvent 2: 10.5% by mass

  When all the particles in hard coat film forming composition 5 are taken as 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0.9% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 5 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 5 was used. Got.

[Example 6]
Each substance was mixed with the following mixing | blendings and the composition 6 for hard-coat film formation of Example 6 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 37.5% by mass
Dispersion liquid of Production Example 5 containing second particles: 7.7% by mass
Monomer: 12.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 33.0% by mass
Solvent 2: 8.3% by mass

  When all the particles in the hard coat film forming composition 6 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 4.5% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 6 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 6 was used. Got.

[Example 7]
Each substance was mixed with the following mixing | blending, and the composition 7 for hard-coat film formation of Example 7 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 45.0% by mass
Dispersion liquid of Production Example 5 containing second particles: 30.9% by mass
Monomer: 5.1% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 14.5% by mass
Solvent 2: 3.6% by mass

  When all the particles in the hard coat film-forming composition 7 are taken as 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 10.7% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 7 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 7 was used. Got.

[Example 8]
Each substance was mixed with the following mixing | blending, and the composition 8 for hard-coat film formation of Example 8 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 45.0% by mass
Dispersion liquid of Production Example 3 containing second particles: 20.6% by mass
Monomer: 5.1% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 22.7% by mass
Solvent 2: 5.7% by mass

  When all the particles in the hard coat film forming composition 8 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. It was.

  Instead of using the hard coat film forming composition 1, the hard coat film of Example 8 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition 8 was used. Got.

[Comparative Example 1]
Each substance was mixed with the following mixing | blending, and composition B1 for hard-coat film formation which does not contain the 1st particle | grains which is the composition for hard-coat film formation of the comparative example 1 was obtained.
Dispersion liquid of Production Example 3 containing second particles: 5.2% by mass
Monomer: 27.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 53.0% by mass
Solvent 2: 13.3% by mass

  When all the particles in the hard coat film-forming composition B1 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. It was.

  Instead of using the hard coat film forming composition 1, the hard coat film of Comparative Example 1 and the plastic substrate provided with the hard coat film were the same as in Example 1 except that the hard coat film forming composition B1 was used. Got.

[Comparative Example 2]
Each substance was mixed with the following mixing | blending, and the composition B2 for hard-coat film formation which does not contain the 1st particle | grains which is a composition for hard-coat film formation of the comparative example 2 was obtained.
Dispersion liquid of Production Example 4 containing second particles: 5.7% by mass
Monomer: 27.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 52.6% by mass
Solvent 2: 13.2% by mass

  When all the particles in the hard coat film forming composition B2 are taken as 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 4.3% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Comparative Example 2 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition B2 is used. Got.

[Comparative Example 3]
Each substance was mixed with the following mixing | blending, and the composition B3 for hard-coat film formation which does not contain the 2nd particle | grains which is a composition for hard-coat film formation of the comparative example 3 was obtained.
1st particle: Methyl ethyl ketone dispersion (ATO content 20% by mass) containing antimony-containing tin oxide (ATO) having an average dispersed particle size of 40 nm and a refractive index of 2.0 82.5% by mass
Monomer: 12.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 3.2% by mass
Solvent 2: 0.8% by mass

  When all the particles in the hard coat film-forming composition B3 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. It was.

  Instead of using the hard coat film forming composition 1, the hard coat film of Comparative Example 3 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition B3 is used. Got.

[Comparative Example 4]
Each substance was mixed with the following mixing | blending, and the composition B4 for hard-coat film formation which does not contain the 2nd particle | grains which is a composition for hard-coat film formation of the comparative example 4 was obtained.
Dispersion liquid of Production Example 1 containing first particles: 41.3% by mass
Monomer: 12.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 36.2% by mass
Solvent 2: 9.0% by mass

  When all the particles in the hard coat film forming composition B4 are 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 0% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. It was.

  Instead of using the hard coat film forming composition 1, the hard coat film of Comparative Example 4 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition B4 is used. Got.

[Comparative Example 5]
Each material is mixed by the following mixing | blending, The composition B5 for hard-coat film formation which does not contain the particle | grains (refractive index 1.9 or more) which is the composition for hard-coat film formation of the comparative example 5 Got.
Dispersion liquid of Production Example 2: 77.3% by mass
Dispersion liquid of Production Example 5 containing second particles: 7.7% by mass
Monomer: 12.6% by mass
Photopolymerization initiator: 0.9% by mass
Solvent 1: 1.2% by mass
Solvent 2: 0.3% by mass

  When all the particles in the hard coat film forming composition B5 are taken as 100% by volume, the content of particles of 150 nm or more and 300 nm or less is 2.4% by volume or less, and the content of particles exceeding 3000 nm is 0% by volume. Met.

  Instead of using the hard coat film forming composition 1, the hard coat film of Comparative Example 5 and the plastic substrate provided therewith are the same as in Example 1 except that the hard coat film forming composition B5 is used. Got.

  From the anti-blocking property, transparency, pencil hardness, scratch resistance, refractive index, surface resistance value, surface roughness Ra, and average height of the plastic substrates obtained in Examples 1 to 8 and Comparative Examples 1 to 5, respectively. Further, the following methods were used to evaluate the characteristics of the number of convex portions higher than the average height and the average diameter of convex portions higher than the average height.

(1) Anti-blocking property [a] Sliding property The coated surfaces of the plastic substrate were rubbed together to perform sensory evaluation. When the plastic substrates were rubbed together, evaluation was given as “る も の” for those that slide very well, “◯” for those that slip, “Δ” for those that do not slide very much, and “×” for those that do not slip.
[B] Pressability The coated surfaces of the plastic base material were rubbed together while pressing strongly, and sensory evaluation was performed. When the plastic substrates are rubbed against each other with strong pressure, “◎” indicates that there is no catching feeling and “◯” indicates that it slides very well, “○” indicates that it slips, and “△” indicates that it does not slip so much. Those not present were evaluated as “x”.

(2) Transparency [a] Total light transmittance The total light transmittance of a plastic base material is based on air, using a haze meter NDH-2000 (manufactured by Nippon Denshoku Co., Ltd.), Japanese Industrial Standard JIS-K-7136. Measured based on The measurement was performed using a test piece obtained by producing a test piece of 100 mm × 100 mm from the produced plastic substrate. The total light transmittance of the PET film used as the substrate was 90.2%.
A: 92.0% or more B: 90.0% or more and less than 92.0% C: 88.0% or more and 90.0% or less D: Less than 88.0% A product whose evaluation result is A is a good product. Yes, as the evaluation result changes from B to D, it shows that the transparency deteriorates.
[B] Haze Value The haze value of the plastic substrate was measured based on Japanese Industrial Standard JIS-K-7136 using a haze meter NDH-2000 (manufactured by Nippon Denshoku Co., Ltd.) based on air. The measurement was performed using a test piece obtained by producing a test piece of 100 mm × 100 mm from the produced plastic substrate. The haze value of the PET film used as the substrate was 0.7%.
The evaluation result of A is a non-defective product, and as the evaluation result changes from B to D, the transparency is deteriorated.
A: Less than 1.0% B: 1.0% or more and less than 1.5% C: 1.5% or more and 2.0% or less D: Greater than 2.0%

(3) Pencil hardness Based on JIS-K-5600-5-4, it measured by 750 gf load.

(4) Scratch resistance On a hard coat film formed on a plastic substrate, # 0000 steel wool was slid 10 times under a load of 250 g / cm ² . The surface of the hard coat film after reciprocation was visually observed, and scratch resistance was evaluated according to the following criteria.
The evaluation result of A is a non-defective product, and as the evaluation result changes from B to E, the hard coat property is low.
A: 0 scratches B: 1-10 scratches C: 11-20 scratches D: 20-30 scratches E: 31 or more scratches

(5) Surface roughness Ra
A range of 20 μm × 20 μm was scanned with an atomic force microscope (AFM) (manufactured by SII, SPA300 / SPI3700) to calculate the surface roughness Ra, and the surface roughness was evaluated according to the following criteria. .
○: Surface roughness Ra is 3 nm or more and 6 nm or less ×: Surface roughness Ra is less than 3 nm

(6) Number of convex portions higher than average height Scan the range of 20 μm × 20 μm with an atomic force microscope, count the number of convex portions higher than the average height, and evaluate the number of convex portions according to the following criteria: went.
○: 300 or more and 1000 or less ×: Less than 300

(7) Average diameter The range of 20 micrometers x 20 micrometers was scanned with the atomic force microscope, the average diameter of the convex part higher than average height was calculated, and the average diameter was evaluated on the following reference | standard.
○: Less than 600 nm ×: 600 nm or more

  FIG. 1 is a view showing an AFM image of the hard coat film of Example 3. FIG. FIG. 2 is a diagram showing an AFM image of the hard coat film of Comparative Example 1. The above-mentioned (5) to (7) were evaluated by measurement capable of obtaining such an AFM image.

(8) Refractive index The reflectance in the visible light region is measured with a spectrophotometer V-570 (manufactured by JASCO Corp.), and the hard coat using the following formula (1) from the lowest reflectance (bottom reflectance). The refractive index of the film was calculated.

(R ₀ ; bottom reflectance, n ₁ ; refractive index of air, n ₂ ; refractive index of hard coat film, n ₃ ; refractive index of substrate)

In the calculation of the refractive index, n ₁ = 1.00 and n ₃ = 1.65 were employed.

(9) Surface resistance value (antistatic property)
Using a resistivity meter (Hiresta IP, manufactured by Dia Instruments Co., Ltd.), the surface resistance value when a voltage of 500 V was applied was measured. What the evaluation result is A is a non-defective product, and as the evaluation results become B and C, the conductivity is inferior.
A: Less than 1 × 10 ¹² Ω / □ B: 1 × 10 ¹² Ω / □ or more and less than 1 × 10 ¹⁴ Ω / □ C: 1 × 10 ¹⁴ Ω / □ or more

  The evaluation results for Examples 1 to 8 are shown in Table 1 below. Moreover, the evaluation result is shown in following Table 2 about the plastic base material of Comparative Examples 1-5.

  First, from the results of Examples 1 to 8 and Comparative Examples 1 to 4, when the surface roughness Ra is 3 nm or more and 6 nm or less, and the number of protrusions higher than the average height is 300 or more, hard coat properties are provided. Further, it was confirmed that the anti-blocking property (sliding property and pressing property) was excellent.

  In addition, since the hard coat films of Comparative Examples 1, 2, and 5 have a refractive index of less than 1.52, it is difficult to use the hard coat film as a film for adjusting the refractive index for suppressing the bone appearance phenomenon.

  From the results of Example 2, it was confirmed that when conductive particles were used as the first particles, conductivity was obtained simultaneously with anti-blocking properties.

  From the above results, according to the plastic substrates of Examples 1 to 8, it can be confirmed that the hard base material and the anti-blocking property are excellent, and the hard coat having a refractive index of 1.55 to 1.69. A film was obtained, and it was confirmed that the present invention was useful.

Claims (7)

The arithmetic average roughness Ra of the surface is 3 nm or more and 6 nm or less,
In the surface, the number of convex portions having a height equal to or higher than the average height is 300 or more and 1000 or less per 400 μm ^{2 of the} surface,
A hard coat film having a refractive index of 1.52 or more.   The hard coat film according to claim 1, which has a haze value of 1.5% or less.   The hard coat film according to claim 1 or 2, wherein an average diameter of the convex portions in a plan view is 600 nm or less.   The plastic base material which has the base-material main body formed using the resin material, and the hard-coat film | membrane of any one of Claim 1 to 3 provided in the at least one surface of the said base-material main body. First particles having a volume-based median diameter (D50) of 5 nm or more and 120 nm or less;
A second particle having a volume-based median diameter (D50) of 500 nm or more and 2000 nm or less;
A curable resin monomer, and
The composition for forming a hard coat film, wherein the first particles are metal oxide particles having a refractive index of 1.9 or more. When all the particles included in the whole range for measuring the volume-based particle size are 100% by volume, the content of particles having a volume-based particle size of 150 nm or more and 300 nm or less is 0% by volume or more and 5% by volume. And
The composition for forming a hard coat film according to claim 5, wherein the content ratio of particles having a volume-based particle diameter exceeding 3000 nm is 0% by volume or more and 5% by volume or less.   A touch panel comprising at least one of the hard coat film according to any one of claims 1 to 3 and the plastic substrate according to claim 4.