TWI609935B - Inorganic particle dispersion, inorganic particle containing composition, coating film, plastic substrate with coating film, display - Google Patents

Abstract

The invention provides an inorganic particle dispersion liquid having a sharp particle size distribution and less water content, a inorganic particle-containing composition, a coating film, a plastic substrate with a coating film, and a display device. This type of inorganic particle dispersion liquid is a dispersion liquid in which inorganic particles are dispersed in a dispersion medium with a dispersant having a hydrolyzable group, which contains an alkaline substance, and the content of water is 1% by mass or less.

Description

Inorganic particle dispersion, composition containing inorganic particles, coating film, plastic substrate with coating film, display device

The present invention relates to an inorganic particle dispersion, an inorganic particle-containing composition, a coating film, a plastic substrate with a coating film, and a display device.

This application claims priority based on Japanese Patent Application No. 2013-202984 for which it applied to Japan on September 30, 2013, and uses the content here.

Inorganic particles such as zirconia, titanium dioxide, and silicon dioxide are dispersed in a binder such as a resin and used.

For example, plastic substrates used in display devices such as liquid crystal displays (LCD), plasma displays (PDP), and electroluminescence displays (EL) require transparency, refractive index, and mechanical properties. Therefore, the following operations are performed: a functional film is formed by coating a plastic substrate with a composition obtained by mixing inorganic fine particles with a high refractive index and a resin.

As a method for compounding inorganic particles and a binder, a common method is to mix a dispersion liquid and a binder, wherein the dispersion liquid is In the presence of water, inorganic particles in which a dispersant having a hydrolyzable group such as an alkoxide is surface-modified are dispersed in a solvent.

Hydrolyzable groups such as alkoxides have the property of adsorbing and dehydrating and condensing on the inorganic particles by hydrolyzed hydroxyl groups by coexisting with water under acidic or basic conditions.

The surface of inorganic particles is usually hydrophilic. In order to complex with the binder and maintain high transparency, it is important to hydrophobize the surface of the inorganic particles with a dispersant or the like to improve the dispersibility of the inorganic particles with respect to the organic solvent.

As such a dispersion liquid, an inorganic particle dispersion liquid is proposed in which a hydrolysis catalyst is added and metal oxide particles are surface-treated with a silane coupling agent (for example, refer to Patent Document 1).

Furthermore, it has been proposed to organically use a silane coupling agent when the metal oxide fine particles are subjected to a bead mill treatment, and to perform an ultrasonic treatment by reacting the metal oxide fine particles with an isocyanate compound having a polymerizable functional group. A dispersion in which metal oxide fine particles are dispersed (see, for example, Patent Document 2).

(Prior technical literature) (Patent Literature)

Patent Document 1: Japanese Patent Application Laid-Open No. 2009-108123

Patent Document 2: Japanese Patent Application Laid-Open No. 2010-254889

However, the dispersion liquid described in the aforementioned Patent Document 1 is subjected to a hydrolysis treatment of the silane coupling agent and then a dispersion treatment, and therefore, There are many processes, and water is contained in the dispersion liquid. Therefore, not only a dispersion liquid having a sharp particle size distribution cannot be obtained, but also long-term storage stability is unstable.

In addition, since it contains a large amount of water, when it is mixed with a binder component such as a resin to form a coating film, foreign matter is easily generated in the appearance of the coating film, and there is a problem that the film forming property is not satisfactory.

The dispersion described in Patent Document 2 has not undergone a hydrolysis process, and therefore has a low water content. However, the desired dispersibility cannot be obtained in the first stage of the dispersing treatment. Therefore, it is necessary to add an isocyanate compound to perform the dispersing treatment again, and the process is complicated. . In addition, since isocyanate compounds react with hydroxyl groups, there is a problem that the solvents that can be used are limited.

The present invention has been made in order to solve the above-mentioned problems, and an object thereof is to provide an inorganic particle dispersion liquid having a sharp particle size distribution and low water content, a composition containing an inorganic particle, a coating film, a plastic substrate with a coating film, and Display device.

The present inventors conducted intensive research in order to solve the above-mentioned problems, and as a result, found that in the dispersion treatment of the inorganic particles, the inorganic particles can be surface-treated and dispersed by using an alkaline substance, whereby the inorganic particles can adsorb water. This minimum amount of water is subjected to surface treatment, so that an inorganic particle dispersion liquid having a sharp particle size distribution and low water content can be obtained, and the number of processes in the dispersion treatment can be reduced to complete the present invention.

that is,

[1] The inorganic particle dispersion liquid of the present invention is an inorganic particle having a hydrolyzable group The dispersant is dispersed in a dispersion medium, wherein the inorganic particle dispersion liquid contains an alkaline substance, and the content of water is 1% by mass or less.

[2] The inorganic particle-containing composition of the present invention is a product containing the inorganic particle dispersion liquid of the present invention and a binder component.

[3] The coating film of the present invention is formed using the inorganic particle-containing composition of the present invention.

[4] The plastic substrate with a coating film of the present invention is provided with the coating film of the present invention on at least one surface of the plastic substrate.

[5] The display device of the present invention includes at least any one of the coating film of the present invention and the base material of the coated film of the present invention.

According to the present invention, it is possible to provide an inorganic particle dispersion liquid having a sharp particle size distribution, excellent dispersion stability of inorganic particles, and excellent long-term storage stability of a dispersion liquid, an inorganic particle-containing composition containing the inorganic particle dispersion liquid, and using the same. A coating film formed by containing an inorganic particle composition, a plastic substrate with a coating film provided with the coating film, and a display device including at least one of a coating film and a substrate with a coating film.

FIG. 1 is a scanning ion microscope image of the upper side of the coating film section of Example 4. FIG.

FIG. 2 is a scanning ion microscope image of the lower side of the coating film section of Example 4. FIG.

FIG. 3 is a reflection spectrum of Example 4 and Comparative Example 4. FIG.

Hereinafter, embodiments will be described.

[Inorganic particle dispersion]

The inorganic particle dispersion liquid of the present embodiment is a dispersion liquid in which inorganic particles are dispersed in a dispersion medium with a dispersant having a hydrolyzable group, which contains an alkaline substance, and the content of water is 1% by mass or less.

The water content of the inorganic particle dispersion liquid of this embodiment is 1% by mass or less, more preferably 0.7% by mass or less, more preferably 0.5% by mass or less, and further preferably 0.4% by mass or less.

If the inorganic particle dispersion contains water in an amount exceeding 1% by mass, not only a dispersion with a sharp particle size distribution will not be obtained, but also the long-term storage stability will be deteriorated. Therefore, the water content of the inorganic particle dispersion is minimized as much as possible. Is better.

The content of water in this embodiment refers to a value titrated by a Karl Fischer moisture analyzer (model: AQL-22320, manufactured by Hiranuma Sangyo Co., Ltd.).

In the inorganic particle dispersion liquid of this embodiment, the value of the particle diameter (D90) when the cumulative volume percentage of the particle size distribution is 90% divided by the cumulative volume percentage of the particle size distribution (50%) is 1 or more And 4 or less is more preferable, 1 or more and 3 or less is more preferable, and 1 or more and 2 or less is more preferable. Here, the particle size distribution refers to the particle size distribution of the inorganic particles contained in the inorganic particle dispersion.

By dividing the particle size (D90) at the cumulative volume percentage of the particle size distribution by 90% by the particle size at the cumulative volume percentage of the particle size distribution of 50% When the value of (D50) is within the above range, the inorganic particles can be uniformly dispersed in the resin, and the refractive index distribution in the film can be made uniform. Thereby, it is possible to reduce color spots such as interference fringes. In addition, since coarse particles are reduced, there is also an effect that foreign matter can be suppressed from occurring during coating.

D50 and D90 in the present embodiment are values measured by a particle size distribution meter (trade name: MICRO TRAK UPA150, manufactured by NIKKISO Co., Ltd.) using the dynamic light scattering method as a measurement principle.

From the viewpoint of improving the transparency of the inorganic particle dispersion liquid, D50 in the inorganic particle dispersion liquid of this embodiment is preferably 1 nm or more and 45 nm or less, and more preferably 1 nm or more and 20 nm or less.

As one embodiment of the inorganic particle dispersion liquid of the present embodiment, an inorganic particle dispersion liquid containing inorganic particles, a dispersant having a hydrolyzable group, an alkaline substance, and a dispersion medium will be described.

"Inorganic particles"

The inorganic particles in this embodiment are not particularly limited, and inorganic particles having desired characteristics can be appropriately selected and used.

For example, when high refractive index performance is imparted to an inorganic particle dispersion, inorganic particles having a refractive index of 1.9 or more are used. Examples of such inorganic particles include zirconia, zinc oxide, iron oxide, copper oxide, titanium oxide, tin oxide, cerium oxide, tantalum oxide, niobium oxide, tungsten oxide, hafnium oxide, hafnium oxide, potassium titanate, and titanium Barium acid, strontium titanate, potassium niobate, lithium niobate, calcium tungstate, antimony-containing tin oxide (ATO), tin-containing indium oxide (ITO) and other metal oxides. Among these, zirconia and titanium oxide are particularly preferable from the viewpoint of high or low refractive index and little influence due to coloring.

When weather resistance is imparted to the inorganic particle dispersion liquid, inorganic particles having ultraviolet shielding properties can be appropriately selected and used. Examples of such inorganic particles include zinc oxide, titanium oxide, iron oxide, and cerium oxide.

When imparting conductivity to the inorganic particle dispersion liquid, a metal oxide having conductivity is used. Examples of such a metal oxide include antimony-containing tin oxide (ATO), tin-containing indium oxide (ITO), and the like.

The average primary particle diameter of the inorganic particles may be appropriately selected according to the application, but in order to be an inorganic particle dispersion having excellent transparency, it is preferably 1 nm or more and 30 nm or less, and more preferably 5 nm or more and 25 nm or less.

In this embodiment, the "average primary particle diameter" means the particle diameter of each particle itself. As a method for measuring the average primary particle diameter, a scanning electron microscope (SEM) or a transmission electron microscope (TEM) can be used to measure the major diameter of each metal oxide particle, for example, 100 or more metal oxide particles The major axis of each is preferably the major axis of each of the 500 metal oxide particles, and a method of calculating an arithmetic mean thereof.

The content of the inorganic particles in the inorganic particle dispersion liquid may be appropriately adjusted according to the application, and is preferably 5 mass% or more and 50 mass% or less, and more preferably 10 mass% or more and 40 mass% or less.

By setting the content of the inorganic particles in the inorganic particle dispersion liquid within the above range, it is possible to obtain good dispersion stability of the inorganic particles in the inorganic particle dispersion liquid.

"Hydrolysable Dispersant"

As the dispersant having a hydrolyzable group in this embodiment, as long as it has a hydrolyzable group and the surface of the inorganic particles is surface-modified and the surface of the particles is hydrophobized to improve the dispersibility of the inorganic particles in a solvent or resin, it is not particularly important. The limitation is, for example, that a dispersant having an alkoxy group is suitably used.

Examples of such a dispersant having an alkoxy group include a metal alkoxide, a silane coupling agent, and a silicone compound.

As the alkoxy group, a methoxy group and an ethoxy group are preferred.

The metal alkoxide is not particularly limited, but an alkoxysilane is preferred.

As the alkoxysilane, tetraalkoxysilane is preferred.

Examples of the tetraalkoxysilane include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, Four second butoxysilane, four third butoxysilane, tetraphenoxysilane, monoethoxytrimethoxysilane, monobutoxytrimethoxysilane, monopentoxytrimethoxysilane, mono Hexyloxytrimethoxysilane, dimethoxydiethoxysilane, dimethoxydibutoxysilane, etc.

Among these, tetramethoxysilane and tetraethoxysilane can be used appropriately because they have a large amount of silicon (Si), are easy to adjust the concentration when dispersed in a solvent, and have high hydrolysis / condensation reactivity. .

These tetraalkoxysilanes may be used individually by 1 type, and may use 2 or more types together.

As a silane coupling agent, as long as it has an alkoxy group, It is not particularly limited, and examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropyltriethoxysilane , P-styryltrimethoxysilane, p-styryltriethoxysilane, 3-propenyloxypropyltrimethoxysilane, 3-propenyloxypropyltriethoxysilane, 3-methyl Propylene ethoxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, and the like.

Examples of the silane coupling agent include allyltrimethoxysilane, allyltriethoxysilane, vinylethyldimethoxysilane, vinylethyldiethoxysilane, and 3-cyclo Oxypropoxypropylethyldimethoxysilane, 3-glycidoxypropyltriethyldiethoxysilane, p-styrylethyldimethoxysilane, p-styrylethyl Diethoxysilane, 3-propenyloxypropylethyldimethoxysilane, 3-propenyloxypropylethyldiethoxysilane, 3-methacryloxypropylethyl Dimethoxysilane, 3-methacryloxypropylethyldiethoxysilane, allylethyldimethoxysilane, allylethyldiethoxysilane, and the like.

Examples of the silane coupling agent include vinyldiethylmethoxysilane, vinyldiethylethoxysilane, 3-glycidoxypropyldiethylmethoxysilane, and 3-cyclo Oxypropoxypropyl diethylethoxysilane, p-styryldiethylmethoxysilane, p-styryldiethylethoxysilane, 3-propenyloxypropyldiethylmethyl Oxysilane, 3-propenyloxypropyldiethylethoxysilane, 3-methacryloxypropyldiethylmethoxysilane, 3-methacryloxypropyldiethyl Ethoxysilane, allyldiethylmethoxysilane, allyldiethylethoxy Silane and so on.

These silane coupling agents may be used singly or in combination of two or more kinds.

The silicone compound is not particularly limited as long as it has an alkoxy group, and a silicone resin or the like having a methoxy group or an ethoxy group can be used.

The amount of the dispersant having an alkoxy group is appropriately adjusted to such an extent that good dispersibility can be obtained. The addition amount of the dispersant having an alkoxy group is, for example, preferably 5 mass% or more and 120 mass% or less, more preferably 10 mass% or more and 110 mass% or less, and 15 mass% or more with respect to the total mass of the inorganic particles. It is more preferably 100% by mass or less.

"Alkaline substances"

As the basic substance in this embodiment, even if it is a substance having a hydrogen ion index (pH) greater than 7 when mixed with water, and the water content of the inorganic particle dispersion liquid is 1% by mass or less, as long as it is a substance that can be uniformly mixed, It is not particularly limited.

Examples of such alkaline substances include hydroxides and amines of alkali metals or alkaline earth metals, and amines are preferred from the viewpoint of ease of handling.

Examples of the hydroxide of an alkali metal or an alkaline earth metal include inorganic alkaline substances such as calcium hydroxide, magnesium hydroxide, manganese hydroxide, aluminum hydroxide, iron hydroxide, potassium hydroxide, and sodium hydroxide.

Examples of the amines include amines, amidines, amine-based dispersants, amine-based surfactants, amine-based monomers, amine-based solvents, and amine-based solvents.

As the amine, any of primary amine, secondary amine, and tertiary amine can be used. Either type can be used in combination, but tertiary amines are more preferred.

As the amidine type monomer, for example, an acrylamide type monomer or a methacrylamide type monomer is suitably used. Examples of such amidoamine type monomers include hydroxyethyl acrylamide, hydroxyethyl methacrylamide, dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamine , N- [3- (dimethylamino) propyl] acrylamidonium, N- [3- (dimethylamino) propyl] methacrylamido, and the like.

The amount of the alkaline substance to be added is appropriately adjusted so that the value of the particle size (D90) at the cumulative volume percentage of the particle size distribution divided by 90% is divided by the value of the particle size (D50) at the cumulative volume percentage of the particle size distribution of 50%. It may be 4 or less, but it is preferable that the inorganic particle dispersion contains an alkaline substance in an amount of 0.01% by mass or more and 1% by mass or less.

Since the inorganic particle dispersion liquid contains an alkaline substance, even if the content of water is a small amount, which is 1% by mass or less, the hydrolysis of dispersants having an alkoxy group such as a silane coupling agent can be promoted. The inorganic particles are dispersed in a dispersion medium.

"Dispersion medium"

The dispersion medium is not particularly limited as long as it easily disperses the inorganic particles and is a substance other than water. Examples of the dispersion medium include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, and propanol; dichloromethane and dichloroethyl Halogenated hydrocarbons such as alkane; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, 2-pentanone, isophorone; esters such as ethyl acetate, butyl acetate; and fiber dissolving agents such as ethyl cellosolve Agents; ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether; amidine solvents, ether ester solvents, resin monomers, resin oligomers, etc.

As a manufacturing method of the inorganic particle dispersion liquid of this embodiment, the method of mechanically mixing the said each material which is a component of an inorganic particle dispersion liquid, and dispersing an inorganic particle in a solvent is mentioned.

Examples of the dispersing device include a stirrer, a revolution mixer, a homogenizer, and an ultrasonic homogenizer.

The inorganic particle dispersion liquid according to this embodiment is an inorganic particle dispersed with a dispersant having a hydrolyzable group in a dispersion medium, and contains an alkaline substance, and the water content is 1% by mass or less, so it has a sharp particle size distribution. Therefore, the dispersion stability of the inorganic particles is excellent, and the stability of the dispersion liquid over a long period of time is excellent.

In the inorganic particle dispersion liquid of this embodiment, the value of the particle diameter (D90) when the cumulative volume percentage of the particle size distribution is 90% divided by the cumulative volume percentage of the particle size distribution of 50% is 1 Above and 4 or less, the dispersion stability of the inorganic particles is more excellent, and the long-term storage stability of the dispersion liquid is more excellent.

In addition, when D50 is 1 nm or more and 45 nm or less, an inorganic particle dispersion liquid having excellent transparency can be obtained.

In addition, when the inorganic particles are particles having a refractive index of 1.9 or more, an inorganic particle dispersion liquid having a high refractive index can be obtained.

In addition, when the inorganic particles are particles having ultraviolet shielding properties, an inorganic particle dispersion liquid having excellent weather resistance can be obtained.

[Composition containing inorganic particles]

The inorganic particle-containing composition of the present embodiment is formed by including the inorganic particle dispersion liquid of the present embodiment and a binder component.

"Binder Ingredients"

The binder component is not particularly limited, and for example, a resin monomer, a resin oligomer, a resin polymer, an organosilicon compound, or a polymer thereof can be appropriately used.

The binder component used in applications such as display devices is not particularly limited as long as it is a monomer and oligomer of a curable resin used in a general hard coating film. The monomer and oligomer of a photocurable resin may be used. As the polymer, monomers and oligomers of a thermosetting resin may be used.

From the viewpoint of easily obtaining a film with high transparency and strong hard coatability, a monomer using a photocurable resin is preferred, and among monomers of a photocurable resin, one having more than one molecule is used. A crosslinkable compound of either one or both of acrylfluorenyl and methacrylfluorenyl is more preferred.

It is not particularly limited as a crosslinkable compound having one or both of acryl and methacryl groups in the molecule, but it is a polyfunctional excellent in reactivity, transparency, weather resistance, and hardness. Acrylate is preferred. Here, polyfunctional means having three or more functional groups. All three or more functional groups may be the same functional group or different functional groups.

Examples of the functional group other than the acrylfluorenyl group and methacrylfluorene group which the crosslinkable compound has include a vinyl group, an allyl group, an allyl ether group, a styryl group, and a hydroxyl group.

Specific examples of the polyfunctional acrylate include (meth) trimethylolpropane triacrylate and (meth) ditrimethylolpropane Polyols such as alkanetetraacrylate, (meth) nepentaerythritol triacrylate, (meth) nepentaerythritol tetraacrylate, (meth) dipentaerythritol hexaacrylate, epoxy (Meth) acrylate, polyester (meth) acrylate, polyurethane acrylate, polysiloxane acrylate, and the like. These polyfunctional acrylates may be used individually by 1 type, and may mix and use 2 or more types.

In the inorganic particle-containing composition of the present embodiment, the functional group is one or two within a range that does not impede the effects of the invention, and a monomer or oligomer and a dispersion which are not included in the above-mentioned monomers may be appropriately contained. Agents, polymerization initiators, antistatic agents, refractive index modifiers, antioxidants, ultraviolet absorbers, light stabilizers, leveling agents, defoamers, inorganic fillers, coupling agents, preservatives, plasticizers, flow adjustments Additives, thickeners, pH adjusters, and polymerization initiators.

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. Non-ionic surfactants, silicon-based surfactants, fluorine-based surfactants, and polymer-based surfactants with amidoamine bonds.

The polymerization initiator can be appropriately selected depending on the type of the monomer used. When a monomer of a photocurable resin is used, a photopolymerization initiator is used. The type and amount of the photopolymerization initiator can be appropriately selected depending on the monomer of the photocurable resin used. Examples of the photopolymerization initiator include benzophenone-based, dione-based, acetophenone-based, benzoin-based, thiaxanthone-based, quinone-based, benzyldimethylketal, and alkylbenzene Ketones, fluorenyl phosphine oxide compounds, phenyl phosphorus oxide compounds, etc. Photopolymerization initiator.

The inorganic particle-containing composition of this embodiment is applied to a substrate to form a coating film. Therefore, in order to easily apply the coating, the viscosity is 0.2 mPa. s and 500mPa. Below s is better, 0.5mPa. s and 200mPa. Below s is more preferable.

If the viscosity of the composition containing inorganic particles is 0.2mPa. s or more, it is preferable that the film thickness at the time of coating film does not become too thin, and the film thickness can be easily controlled. On the other hand, if the viscosity of the composition containing inorganic particles is 500 mPa. Below s, the viscosity does not become too high, and the inorganic particle-containing composition can be easily handled during coating, so it is preferable.

The viscosity of the inorganic particle-containing composition is preferably adjusted to the above range by appropriately adding an organic solvent to the inorganic particle-containing composition.

The organic solvent is not particularly limited as long as it is an organic solvent having good compatibility with the inorganic particle-containing composition, and examples thereof include aliphatic hydrocarbons such as hexane, heptane, and cyclohexane; and aromatics such as toluene and xylene. Family hydrocarbons; alcohols such as methanol, ethanol, propanol; halogenated hydrocarbons such as dichloromethane, dichloroethane; acetone, methyl ethyl ketone, methyl isobutyl ketone, 2-pentanone, isophorone and other ketones Types; esters such as ethyl acetate and butyl acetate; cellulosics such as ethyl cellosolve; ethers such as propylene glycol monomethyl ether and propylene glycol monoethyl ether; amidine solvents and ether ester solvents. These solvents may be used individually by 1 type, and may mix and use 2 or more types.

According to the inorganic particle-containing composition according to this embodiment, the inorganic particles containing the inorganic particles of this embodiment have sharp particle size distribution. Sub-dispersion liquid, so the dispersion stability of the inorganic particles is excellent, and the composition has excellent long-term storage stability.

[Manufacturing method of inorganic particle-containing composition]

As a manufacturing method of the inorganic particle containing composition of this embodiment, the method of mechanically mixing the said each material as a component of an inorganic particle containing composition is mentioned.

Examples of the mixing device include a mixer, a rotation-revolution mixer, a homogenizer, and an ultrasonic homogenizer.

[Coating film]

The coating film of this embodiment is formed using the inorganic particle-containing composition of this embodiment.

The film thickness of the coating film can be appropriately adjusted depending on the application, and is usually preferably 0.01 μm or more and 20 μm or less, and more preferably 1 μm or more and 10 μm or less.

The method for producing a coating film according to this embodiment includes a process of forming a coating film by applying the inorganic particle-containing composition to a coating object, and a process of hardening the coating film.

As a coating method for forming a coating film, for example, a bar coating method, a flow coating method, a dip coating method, a spin coating method, a roll coating method, a spray coating method, a meniscus coating method, a gravure coating method, and a suction method can be used. Common wet coating methods such as coating method and brush coating method.

As a hardening method for hardening a coating film, it can select suitably according to the kind of adhesive component, and the method of heat hardening or light hardening can be used.

The energy rays used for photo-hardening are not particularly limited as long as they can harden the coating film. For example, ultraviolet rays, far infrared rays, near ultraviolet rays, infrared rays, X-rays, gamma rays, electron rays, proton beams, neutron beams, and the like can be used. Energy rays. Among these energy rays, the use of ultraviolet rays is preferred from the viewpoints of faster curing speed and easier device acquisition and operation.

When cured on ultraviolet irradiation may be used include 200nm to 500nm to produce an ultraviolet wavelength band of the high pressure mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp or the like, to ultraviolet irradiation energy 100 to 3,000mJ / cm ² of the Method, etc.

In the coating film of this embodiment, since the inorganic particles having a sharp particle size distribution in this embodiment, in other words, in the inorganic particle-containing composition, the size of the inorganic particles is substantially uniform, it is easy for the inorganic particles to have no gaps in the coating film. It is evenly filled. Therefore, the film forming property of the coating film is excellent, and the performance of the entire area within the film surface becomes uniform. Therefore, for example, since the refractive index in the film surface becomes substantially uniform, it is possible to suppress the occurrence of stains on the coating film, and it is possible to improve visibility when applied to a display device or the like.

In the coating film of this embodiment, since inorganic particles having a sharp particle size distribution are used, the inorganic particles are uniformly filled in the film, and there are few voids in the film. Therefore, for example, when it is intended to increase the refractive index by using inorganic particles having a refractive index of 1.9 or more, the amount of inorganic particles required to increase the refractive index can be reduced as compared with the past. Therefore, even in a thin film such as 10 nm to 200 nm, the inorganic particles are uniformly filled in the entire coating film, so that the voids in the film can be reduced uniformly, and the refractive index of the coating film can be increased.

In addition, in the coating film of this embodiment, the properties of all parts in the film surface Since it can be made uniform, even if it is a thick film having a film thickness of 1 μm or more, the occurrence of optical unevenness can be suppressed.

That is, the coating film of this embodiment may be a thin film for adjusting the refractive index, or a thick film that can adjust the refractive index and also has a hard coating property, and can be appropriately selected and used according to the application.

Since the coating film according to this embodiment is formed using the inorganic particle-containing composition according to this embodiment, a coating film having excellent film-forming properties can be obtained.

[Plastic substrate with coating film]

The plastic substrate with a coating film of this embodiment includes a base body (plastic substrate) formed using a resin material, and a coating film of this embodiment provided on at least one surface of the base body.

A coating film is formed by applying the inorganic particle-containing composition of the present embodiment to a base body by a known coating method, and a plastic substrate with a coating film is obtained by curing the coating film.

The substrate body is not particularly limited as long as it is a plastic substrate, and examples thereof include polyethylene terephthalate, cellulose triacetate, acrylic acid, acrylic-styrene copolymer, and acrylonitrile-butadiene-styrene. Copolymer, polystyrene, polyethylene, polypropylene, polycarbonate, vinyl chloride and other plastic formers.

When used for display device applications, it is preferred to use a transparent plastic substrate as the substrate body.

The base body may be either sheet-like or film-like, but a film-like shape is preferred.

When the measurement is performed on the basis of air, the haze value of the plastic substrate with the coating film of this embodiment is preferably 1.4% or less, and more preferably 1.0% or less.

Here, the "haze value" refers to the ratio (%) of diffused transmitted light to total light transmitted light, and refers to the use of a haze meter NDH-2000 (manufactured by NIPPON DENSHOKU INDUSTRIES Co., Ltd.) based on air. Value measured based on Japanese Industrial Standard JIS-K-7136.

In the plastic substrate with a coating film of this embodiment, The difference between the maximum value and the minimum value of the reflectance in the range of 500 nm to 750 nm is preferably 1% or less, more preferably 0.8% or less, and still more preferably 0.7% or less.

When the difference between the maximum value and the minimum value of the reflectance of the plastic substrate with a coating film in the range of 500 nm to 750 nm is 1% or less, the plastic substrate with a coating film in this embodiment can suppress interference by light. The occurrence of the ripples is preferable because a coating film with suppressed stains can be obtained.

The plastic substrate with a coating film according to this embodiment may be provided with a hard coating film between the plastic substrate and the coating film, or a film having a property different from that of the coating film may be laminated.

According to the plastic substrate with a coating film according to the present invention, since the coating film of this embodiment is formed, a plastic substrate with a coating film having excellent film-forming properties can be obtained.

[Display device]

The display device of this embodiment is at least one of a plastic substrate provided with the coating film of this embodiment and the coating film with a coating film of this embodiment, that is, this One or both of the coating film of the embodiment and the plastic substrate with a coating film of the present embodiment.

The display device is not particularly limited. In this embodiment, a liquid crystal display device for a touch panel is described.

[Touch panel]

When the refractive index difference between the ITO electrode and the transparent substrate (a plastic substrate such as polyethylene terephthalate) is large, a so-called pattern visualization phenomenon in which the ITO electrode portion is easily observed on the touch panel occurs.

Therefore, by providing the coating film of this embodiment in which the inorganic particles having a refractive index of 1.9 or more are selected as a layer between the transparent substrate and the ITO electrode, it is possible to reduce the refractive index difference between the transparent substrate and the ITO electrode and suppress the pattern. Visualize the phenomenon.

The method of providing any one or both of the coating film of this embodiment and the plastic substrate with a coating film of this embodiment on the touch panel is not particularly limited, and the packaging may be performed by a known method. For example, a structure in which an ITO electrode is patterned on a coating film surface of a plastic substrate with a coating film according to this embodiment, and an alignment film and a liquid crystal layer are laminated.

The display device according to this embodiment includes at least one of the coating film of this embodiment and the plastic substrate with a coating film of this embodiment having excellent film-forming properties. Therefore, the display device has almost no optical characteristics in the coating film surface. This makes it possible to obtain a display device having excellent visibility.

[Example]

Hereinafter, the present invention will be specifically described using examples and comparative examples, but the present invention is not limited to these examples.

[Example 1]

"Inorganic Particle Dispersion"

30% by mass of zirconia (average primary particle diameter: 12 nm, manufactured by Sumitomo Osaka Cement Co., Ltd.), 6.0% by mass of 3-methacryloxypropyltrimethoxysilane, and 0.4% by mass of alkyldimethylamine % And propylene glycol monomethyl ether 63.6 mass% were mixed, and then subjected to a dispersion treatment using a bead mill to obtain an inorganic particle dispersion liquid of Example 1.

"Evaluation of Inorganic Particle Dispersion"

The moisture content of the obtained inorganic particle dispersion liquid was measured with a Karl Fischer moisture analyzer (model: AQL-22320, manufactured by Hiranuma Sangyo Co., Ltd.), and the water content was 0.3% by mass.

The particle size distribution of the obtained inorganic particle dispersion liquid was measured with a particle size distribution meter (trade name: MICRO TRAK UPA150, manufactured by NIKKISO Co., Ltd.), and D50 was 25 nm, D90 was 35 nm, and D90 / D50 was 1.4.

The particle size distribution characteristics of this inorganic particle dispersion after 6 months were the same, and it was confirmed that the long-term storage stability was excellent. The evaluation results are shown in Table 1.

"Composition containing inorganic particles"

5.4% by mass of the obtained inorganic particle dispersion liquid, 0.19% by mass of dipentaerythritol hexaacrylate, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propanyl) -Benzyl] phenyl} -2-methyl-1-acetone 0.02% by mass and propylene glycol monomethyl ether 94.39% by mass were mixed to obtain an inorganic particle-containing composition of Example 1.

"Plastic substrate with coating film"

40% by mass of dipentaerythritol hexaacrylate, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propanyl) -benzyl] phenyl} -2- 2% by mass of methyl-1-acetone and 58% by mass of methyl isobutyl ketone were mixed to obtain a composition for forming a hard coat film.

The composition for forming a hard coating film was applied to a polyethylene terephthalate film having a thickness of 100 μm so that the dry film thickness became 1 μm by a bar coating method, and dried by heating at 90 ° C. Thereby, a coating film is formed.

Next, a high-pressure mercury lamp (120 W / cm) was used to expose ultraviolet rays to the coating film so as to have an energy of 250 mJ / cm ² to harden the coating film, thereby obtaining a substrate with a hard coating film.

Next, the inorganic particle-containing composition of Example 1 was applied to the hard coating film of the base material with a hard coating film so as to have a dry film thickness of 100 nm by a bar coating method, and heated at 90 ° C. to It is allowed to dry to form a coating film.

Next, using a high-pressure mercury lamp (120 W / cm), ultraviolet rays were exposed on the coating film so as to have an energy of 250 mJ / cm ² to harden the coating film, thereby obtaining a plastic substrate with a coating film of Example 1.

"Evaluation of coated plastic substrates"

"Total light transmittance and haze value of plastic substrate with coating film"

Based on air, the total light transmittance and haze value of the plastic substrate with coating film were measured using a haze meter NDH-2000 (manufactured by NIPPON DENSHOKU INDUSTRIES Co., Ltd.) based on Japanese Industrial Standard JIS-K-7136 .

When measuring the total light transmittance and haze value, a 100 mm × 100 mm test piece was made from the produced plastic substrate with a coating film, and the test piece was used.

The evaluation results are shown in Table 1.

"Refractive index of coating film"

The refractive index of the coating film was measured using PRISM COUPLER MODEL 2010 (manufactured by Metricon).

"Stain of plastic substrate with coating film"

Regarding the stain of the plastic substrate with a coating film, the distance between the substrate and the eye was set to 30 cm, and the visual observation was carried out. If there were no stain or almost no stain was observed, it was evaluated as ○, and there were stains. The evaluation was ×.

The evaluation results are shown in Table 1.

"Determination of reflection spectrum of coated plastic substrate"

With respect to the plastic substrate with a coating film of Example 1, a reflection spectrum in a range of 500 nm to 750 nm was measured using a spectrophotometer (trade name: V-570, manufactured by JASCO Corporation).

As a result, the difference between the maximum value and the minimum value of the reflectance of the coated plastic substrate in the range of 500 nm to 750 nm was 1% or less.

[Example 2]

"Inorganic Particle Dispersion"

30% by mass of zirconia (average primary particle diameter 12 nm, manufactured by Sumitomo Osaka Cement Co., Ltd.), 4.5% by mass of 3-methacryloxypropyltrimethoxysilane, 0.4% by mass of amine-based dispersant, After mixing 65.1% by mass of methyl isobutyl ketone, dispersion treatment was performed using a bead mill to obtain To the inorganic particle dispersion liquid of Example 2.

"Evaluation of Inorganic Particle Dispersion"

As a result of evaluation in the same manner as in Example 1, the water content was 0.3% by mass.

In addition, D50 was 18 nm, D90 was 25 nm, and D90 / D50 was 1.4.

This inorganic particle dispersion had the same particle size distribution characteristics after 6 months, and was confirmed to have excellent long-term storage stability. The evaluation results are shown in Table 1.

"Plastic substrate with inorganic particle composition and coating film"

Except that the inorganic particle dispersion liquid of Example 2 was used, the same procedure as in Example 1 was performed to obtain an inorganic particle-containing composition of Example 2 and a plastic substrate with a coating film of Example 2.

"Evaluation of coated plastic substrates"

About the plastic substrate with a coating film of Example 2, the total light transmittance, the haze value, the refractive index of a coating film, and the stain of the plastic substrate with a coating film were evaluated similarly to Example 1.

The evaluation results are shown in Table 1.

In addition, as a result of measuring the reflection spectrum of the plastic substrate with a coating film in the range of 500 nm to 750 nm in the same manner as in Example 1, the difference between the maximum value and the minimum value of the reflectance of the plastic substrate with a coating film was 1% or less. .

[Example 3]

Zinc oxide (trade name: ZnO650, average primary particle size: 25 nm, manufactured by Sumitomo Osaka Cement Co., Ltd.) 10% by mass, 10% by mass of tetramethoxysilane, and 0.4% by mass of dimethylaminopropylacrylamide Isopropanol After mixing at 77.6 mass%, the dispersion treatment was performed using a bead mill to obtain the inorganic particle dispersion liquid of Example 3.

"Evaluation of Inorganic Particle Dispersion"

As a result of evaluation in the same manner as in Example 1, the water content was 0.3% by mass.

In addition, D50 was 30 nm, D90 was 90 nm, and D90 / D50 was 3.0.

This inorganic particle dispersion had the same particle size distribution characteristics after 6 months, and was confirmed to have excellent long-term storage stability. The evaluation results are shown in Table 1.

[Example 4]

"Composition containing inorganic particles"

58% by mass of the inorganic particle dispersion liquid of Example 2, 11% by mass of dipentaerythritol hexaacrylate, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propanyl) ) -Benzyl] phenyl} -2-methyl-1-acetone 0.5% by mass and propylene glycol monomethyl ether 30.5% by mass were mixed to obtain an inorganic particle-containing composition of Example 4.

"Plastic substrate with coating film"

This inorganic particle-containing composition of Example 4 was applied to a polyethylene terephthalate film having a thickness of 100 μm so as to have a dry film thickness of 1.5 μm by a bar coating method, and heated at 90 ° C. so that It dries to form a coating film.

Next, using a high-pressure mercury lamp (120 W / cm), ultraviolet rays were exposed on the coating film so as to have an energy of 250 mJ / cm ² to harden the coating film, thereby obtaining a plastic substrate with a coating film of Example 4.

For the plastic substrate with coating film of Example 4, and implementation Example 1 The total light transmittance, haze value, and stain of the plastic substrate with a coating film were evaluated in the same manner. The refractive index of the coating film was measured using an Abbe-type refractive index meter (model: DR-M2, manufactured by ATAGO Co., Ltd.).

The evaluation results are shown in Table 1.

"Observation of Filled State of Inorganic Particles in Coating Film"

In order to confirm the filling state of the inorganic particles in the coating film, the cross section of the film was observed using a beam ion beam processing observation device. A scanning ion microscope image of the upper side of the coating film section is shown in FIG. 1, and a scanning ion microscope image of the lower side of the coating film section is shown in FIG. 2.

From the scanning ion microscope images shown in FIGS. 1 and 2, it was confirmed that the inorganic particles were filled in the coating film without gaps.

"Determination of reflection spectrum of coated plastic substrate"

With respect to the plastic substrate with a coating film of Example 4, a reflection spectrum in a range of 500 nm to 750 nm was measured using a spectrophotometer (trade name: V-570, manufactured by JASCO Corporation).

The results are shown in FIG. 3.

As a result, the difference between the maximum value and the minimum value of the reflectance of the coated plastic substrate in the range of 500 nm to 750 nm was 0.5%.

[Comparative Example 1]

4.5% by mass of 3-methacryloxypropyltrimethoxysilane and 65.5% by mass of methyl ethyl ketone were used instead of 6.0% by mass of 3-methacryloxypropyltrimethoxysilane and alkyldimethylamine Except for 0.4% by mass and 63.6% by mass of propylene glycol monomethyl ether, it was carried out in the same manner as in Example 1. To prepare an inorganic particle dispersion liquid of Comparative Example 1 containing no alkaline substance, Even when dispersed by a bead mill, the inorganic particles were still settled, and a dispersion liquid was not obtained.

[Comparative Example 2]

4.5% by mass of 3-methacryloxypropyltrimethoxysilane, 3% by mass of an aqueous solution containing 1% by mass of sodium hydroxide, and 62.5% by mass of methyl ethyl ketone were used instead of 3-methacryloxypropyltrimethyl Except for 6.0% by mass of oxysilane, 0.4% by mass of alkyldimethylamine, and 63.6% by mass of propylene glycol monomethyl ether, the same procedure as in Example 1 was performed to obtain an inorganic particle dispersion liquid of Comparative Example 2 containing a large amount of water. .

"Evaluation of Inorganic Particle Dispersion"

As a result of evaluation in the same manner as in Example 1, the water content was 3.3% by mass.

In addition, D50 was 30 nm, D90 was 135 nm, and D90 / D50 was 4.5.

In this inorganic particle dispersion liquid, inorganic particles settled after 2 months, and it was confirmed that long-term dispersion stability was not satisfactory. The evaluation results are shown in Table 1.

"Plastic substrate with inorganic particle composition and coating film"

Except that the inorganic particle dispersion liquid of Comparative Example 2 was used, it was performed in exactly the same manner as in Example 1 to obtain an inorganic particle composition of Comparative Example 2 and a plastic substrate with a coating film of Comparative Example 2.

"Evaluation of coated plastic substrates"

About the plastic substrate with a coating film of Comparative Example 2, the total light transmittance, the haze value, the refractive index of the coating film, and the stain of the plastic substrate with a coating film were evaluated.

The evaluation results are shown in Table 1.

In addition, as a result of measuring the reflection spectrum of the plastic substrate with a coating film in the range of 500 nm to 750 nm in the same manner as in Example 1, the difference between the maximum value and the minimum value of the reflectance of the plastic substrate with a coating film exceeded 1%.

[Comparative Example 3]

4.5% by mass of 3-methacryloxypropyltrimethoxysilane, 3% by mass of an aqueous solution containing 1% by mass of acetic acid, and 62.5% by mass of methyl ethyl ketone were used instead of 3-methacryloxypropyltrimethoxy Except for 6.0% by mass of silane, 0.4% by mass of dimethylamine, and 63.6% by mass of propylene glycol monomethyl ether, the same procedure as in Example 1 was performed, and Comparative Example 3 containing a large amount of water and containing no alkaline substance was prepared Inorganic particle dispersion liquid, but even when dispersed by a bead mill, the inorganic particles still sedimented, and a dispersion liquid could not be obtained.

[Comparative Example 4]

"Composition containing inorganic particles"

60% by mass of the inorganic particle dispersion liquid of Comparative Example 2, 11% by mass of dipentaerythritol hexaacrylate, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propanyl) ) -Benzyl] phenyl} -2-methyl-1-acetone 0.5% by mass and propylene glycol monomethyl ether 28.5% by mass were mixed to obtain an inorganic particle-containing composition of Comparative Example 4.

"Plastic substrate with coating film"

This inorganic particle-containing composition of Comparative Example 4 was applied to a polyethylene terephthalate film having a thickness of 100 μm so that the dry film thickness became 1.5 μm by a bar coating method, and heated at 90 ° C. so that It dries to form a coating film.

Next, using a high-pressure mercury lamp (120 W / cm), ultraviolet rays were exposed on the coating film so as to have an energy of 250 mJ / cm ² to harden the coating film, thereby obtaining a plastic substrate with a coating film of Comparative Example 4.

About the plastic substrate with a coating film of Comparative Example 4, the total light transmittance, the haze value, and the stain of the plastic substrate with a coating film were evaluated in the same manner as in Example 1. The refractive index of the coating film was measured using an Abbe-type refractive index meter (model: DR-M2, manufactured by ATAGO Co., Ltd.).

The evaluation results are shown in Table 1.

"Determination of reflection spectrum of coated plastic substrate"

With respect to the plastic substrate with a coating film of Comparative Example 4, a reflection spectrum in the range of 500 nm to 750 nm was measured using a spectrophotometer (trade name: V-570, manufactured by JASCO Corporation).

The results are shown in FIG. 3.

As a result, the difference between the maximum value and the minimum value of the reflectance of the coated plastic substrate in the range of 500 nm to 750 nm was 1.7%.

From the results in Table 1, it can be confirmed as follows: If Example 1 to Example 3 and Comparative Example 1 to Comparative Example 3 are compared, the inorganic particle dispersion liquids of Examples 1 to 3 have excellent dispersion stability of inorganic particles, The dispersion is excellent in long-term storage stability.

From the results in Table 1, it can be confirmed that if Example 1 and Examples 2 and 2 are compared, compared with Comparative Example 2, in Examples 1 and 2, the total light transmittance, haze value, and coating film Refractive index and stain of plastic substrate with coating film have been improved.

Furthermore, when the reflection spectrum of Example 4 and the reflection spectrum of Comparative Example 4 are compared, it can be confirmed that even if the film thickness is set to a thickness of 1.5 μm, for example, In the film, in the plastic substrate with a coating film of Example 4, the amplitude of the ripple caused by the interference of light is also small, and it can be seen by visual inspection that the stain is suppressed.

In addition, in order to adjust Comparative Example 4 to the same refractive index as that of Example 4, the content of zirconia in Comparative Example 4 needs to be increased. It can be confirmed that in Example 4, refraction can be increased with a smaller amount of zirconia than conventional films. rate.

[Industrial availability]

The inorganic particle dispersion liquid of the present invention can be applied to all industrial applications in which inorganic particle dispersion liquids have been conventionally used, and can be applied to, for example, optical film applications, residential exterior applications, heat ray shielding applications, and the like.

Since the picture in this case is a scanning ion microscope image, it is not a representative picture in this case. Therefore, there is no designated representative map in this case.

Claims (7)

An inorganic particle dispersion liquid is obtained by dispersing inorganic particles in a dispersing medium other than water with a dispersant having a hydrolyzable group. The inorganic particles are selected from the group consisting of iron oxide, copper oxide, titanium oxide, tin oxide, cerium oxide, Tantalum oxide, niobium oxide, tungsten oxide, hafnium oxide, hafnium oxide, potassium titanate, barium titanate, strontium titanate, potassium niobate, lithium niobate, calcium tungstate, antimony tin oxide (ATO), tin oxide Particles composed of a compound of indium (ITO); the inorganic particle dispersion liquid contains an alkaline substance, and the content of water is 1% by mass or less. The inorganic particle dispersion liquid according to item 1 of the scope of patent application, wherein the particle size (D90) at the cumulative volume percentage of the particle size distribution is divided by the particle size (D50) at the cumulative volume percentage of the particle size distribution of 50% The value of) is 1 or more and 4 or less. An inorganic particle-containing composition, which is composed of the inorganic particle dispersion liquid and the binder component described in the first or second aspect of the patent application. A coating film formed by using the inorganic particle-containing composition described in item 3 of the scope of patent application. A plastic substrate with a coating film is provided with at least one surface of the plastic substrate with a coating film described in item 4 of the scope of patent application. The plastic substrate with a coating film according to item 5 of the scope of patent application, wherein the difference between the maximum value and the minimum value of the reflectance in the range of 500 nm to 750 nm is 1% or less. A display device includes at least one of the coating film described in item 4 of the patent application scope and the plastic substrate with a coating film described in item 5 or 6 of the patent application scope.