KR101774067B1 - Process for production of silica-alumina sol, silica-alumina sol, coating agent for formation of transparent coating film which comprises the sol, and substrate having transparent coating film attached thereto - Google Patents

Abstract

A silica-alumina sol which is stable even at a high concentration and has good dispersibility into a matrix component, and a process for producing the same. Silica-alumina particles obtained by removing cations (alkali metal ions) present in the silica-alumina sol derived from the raw material for production and reducing the amount of boron ions and adjusting the surface negative charge amount to a predetermined range are used, The compound is preliminarily adsorbed on the surface of the particle, and the surface is hydrolyzed.

Description

TECHNICAL FIELD [0001] The present invention relates to a silica-alumina sol, a silica-alumina sol, a coating for forming a transparent coating film containing the sol, and a transparent film- FILM WHICH COMPRISES THE SOL, AND SUBSTRATE HAVING TRANSPARENT COATING FILM ATTACHED THERETO}

The present invention relates to a method for producing a silica-alumina sol which is stable at a high concentration, a silica-alumina sol, a coating for forming a transparent film containing the sol, and a substrate with a transparent coating film.

More specifically, it is stable at a high concentration and has good dispersibility into a matrix component. Therefore, it is possible to increase the concentration of the coating film for forming a transparent film, and to coat the film at a high concentration, A process for producing silica-alumina sol which can be suitably used for the production of a substrate with a transparent coating film excellent in adhesion to base material, scratch resistance, film hardness, film strength, transparency, haze and the like , Silica-alumina sol, a coating for forming a transparent film containing the sol, and a substrate with a transparent coating film.

BACKGROUND ART It is known to form a transparent coating film having a hard coat function on the surface of a substrate in order to improve scratch resistance of a substrate surface such as glass, a plastic sheet, a plastic lens, and a display device. Specifically, an organic resin film or an inorganic film having transparency is formed on the surface of a glass, a plastic, a display device substrate, or the like. At this time, resin particles or inorganic fine particles such as silica are mixed in the organic resin film or the inorganic film to further improve the adhesion to the base material, scratch resistance, and the like.

Further, in order to suppress interference fringes, it has been attempted to reduce the refractive index difference from the base material by blending composite oxide particles of high refractive index such as titanium oxide or zirconium oxide or high refractive index.

In order to impart antistatic performance, conductive inorganic oxide particles such as antimony pentoxide, tin-doped indium oxide, and antimony doped tin oxide are mixed.

When such inorganic oxide particles are used, surface treatment with a silane coupling agent is carried out in order to improve dispersibility into a matrix component.

Further, in order to improve the stability of the silica sol, there has been known a method of modifying the surface of the silica particles with aluminum. For example, Patent Document 1 discloses a method in which an acidic silica sol prepared by a post- Silica sol having a pH of 4 to 5 obtained by heating after mixing an aqueous solution is described.

In Patent Document 2, a silica sol aqueous solution having a pH of 6 or more is treated with a cation exchange resin having an ammonia type or an amine type, a metal salt of aluminic acid is added and heat treatment is performed at 70 ° C or higher to prepare a stable silica sol in an acidic or neutral region Is described.

In the silica sol described in Patent Documents 1 and 2, the stability is improved by covering the surface of the silica particles with aluminum hydroxide or alumina. However, since such silica particles have a positive charge on the particle surface, Group, there is a problem that coagulation is likely to occur and transparency in the coating composition is lowered.

In addition, conventional paints containing the particles have a problem in that they are not suitable for formation of a thick film because there is a limit to a high concentration.

The stability is inadequate even if the concentration can be increased, and the adhesion of the obtained transparent coating film to the base material, the film strength, the scratch resistance and the like are sometimes lowered. In addition, when the concentration is increased, the viscosity increases and the coating properties are lowered. As a result, the adhesion to the base material, the film strength, the scratch resistance and the like may be lowered.

U.S. Patent No. 4451388 Japanese Patent Laid-Open Publication No. 58-110415

The inventors of the present invention have made intensive investigations in view of the above problems, and as a result, they have found that it is possible to remove cations (alkali metal ions) present in the silica-alumina sol derived from the raw materials for production, reduce contamination ions, The particles obtained by adsorbing the organosilicon compound to the surface of the particles in advance and hydrolyzing the particles after the surface treatment can stabilize the dispersion liquid at a higher concentration than that of the conventional particles, And that the coating liquid using the coating liquid can be highly concentrated, and thus the present invention has been accomplished.

The present invention provides a transparent film-forming coating material which is stable even at a high concentration and has good dispersibility into a matrix component. Therefore, the transparent film-forming coating material can be highly concentrated, and such a coating material is excellent in coatability and can be formed into a thick film, A method of producing a silica-alumina sol which can be suitably used for producing a transparent-film-adhered base material excellent in adhesion, scratch resistance, film hardness, film strength, transparency and haze, And an object of the present invention is to provide a coating material and a substrate with a transparent coating film.

The method for producing silica-alumina sol according to the present invention is characterized by comprising the following steps (a) to (f).

(a) silica-alumina fine particles having an average particle diameter in the range of 5 to 100 nm and an alumina content in the particles in the range of 0.01 to 5% by weight in terms of Al ₂ O ₃ have a solid content concentration of 1 (Excluding H ⁺ , OH ^- ) in an amount of not more than 50 ppm in the silica-alumina fine particles with an ion-exchange resin

(b) a step of subjecting the silica-alumina fine particle water dispersion to solvent substitution with alcohol

(c) adding to the silica-alumina fine particle alcohol dispersion an organosilicon compound represented by the following formula (1) in an amount of 1 to 50% by weight of silica-alumina fine particles as R _n -SiO _(4-n) fair

R _n -SiX _{4 -n} (1)

X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen atom, a hydrogen atom, and n is an integer of 1 to 3 (preferably 1 to 3), wherein R is a non-substituted or substituted hydrocarbon group having 1 to 10 carbon atoms, Lt;

(d) a step of adsorbing the organosilicon compound on silica-alumina fine particles while stirring the dispersion of silica-alumina fine particle alcohol

(e) a step of hydrolyzing an organosilicon compound by adding water and a catalyst for hydrolysis;

(f) a step of aging at 40 to 120 DEG C for 0.5 to 24 hours

It is preferable that the step (a) comprises the following steps (a1) and (a2).

(a1) a step of treating with a cation exchange resin so that the pH is in the range of 1.0 to 6.0

(a2): a step of treating the dispersion with an anion exchange resin so that the pH of the dispersion is higher than the pH of the dispersion in the step (a1) and in the range of 2.0 to 7.0

Following the step (f), it is preferable to carry out the following step (g) and / or (h).

(g) Substitution with an organic solvent

(h) Concentration process

It is preferable that the negative charge amount per unit surface area of the silica-alumina fine particles of the silica-alumina fine particle water dispersion obtained in the step (a) is in the range of 0.1 to 1.5 占 q ec / m2 at pH 2.0 to 7.0.

It is preferable that the molar ratio (M _H2O ) / (M _OC ) of the number of moles of water (M _H2O ) and the number of moles of the organosilicon compound (M _OC ) in the step (e) is in the range of 1 to 300.

The catalyst for hydrolysis of ammonia in the above step (e), the number of moles of ammonia _(NH3 M) and the number of moles of the organic silicon compound with a molar ratio _{(M OC) (M NH3)} / (M OC) in the range of 0.1 to 12 .

When the negative charge amount per unit surface area of the silica-alumina fine particles of the silica-alumina fine particle water dispersion obtained in the step (f) is 0.5 to 2.0 Micro-coulombs when measured with a dispersion having a solid concentration of 0.5% by weight and a pH of 7.5 ± 1.5 / Cm < 2 >.

It is preferable that the organic solvent in the step (g) is one or more kinds selected from ethers, esters, ketones and alcohols.

It is preferable that the solid concentration is in the range of 20 to 70% by weight and the viscosity is in the range of 1 to 10,000 cp.

The silica-alumina sol according to the present invention has an average particle diameter in the range of 5 to 100 nm, an alumina content in the particles in the range of 0.01 to 5% by weight in terms of Al ₂ O ₃ , (Q ₁ ) per unit surface area of the surface-treated silica-alumina fine particles and a unit surface area of the silica-alumina fine particles before being surface-treated with the organosilicon compound (Ratio) (Q ₁ ) / (Q ₂ ) of the negative charge amount to the appropriate negative charge amount (Q ₂ ) is in the range of 0.2 to 0.8.

R _n -SiX _{4 -n} (1)

X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen, a hydrogen, and n is an integer of 1 to 3), R < 1 > is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms,

Wherein the negative charge (Q ₁ ) is in the range of 0.5 to 2.0 Micro-coulombs / cm 2 when measured by a dispersion having a solid concentration of 0.5 wt% and a pH of 7.5 ± 1.5. Alumina sol.

The coating film for forming a transparent film according to the present invention comprises the silica-alumina sol described in any one of the above, a matrix-forming component and a dispersion medium, wherein the total solid concentration is in the range of 30 to 70 wt% The concentration of the component is in the range of 6 to 63 wt% as solid content and the concentration of the silica-alumina fine particle is in the range of 3 to 56 wt% as solid content.

It is preferable that the matrix-forming component is a silicon-based matrix-forming component or an organic resin matrix-forming component, and it includes a polyfunctional acrylate resin or a polyfunctional silicone resin.

In addition, it is preferable to contain 0.003 to 0.7% by weight of a silicone antifouling agent as a solid content.

In addition, it is preferable to include a leveling agent in an amount of 0.003 to 0.56% by weight as a solid content.

It is preferable that the dispersion medium is one or more kinds selected from ethers, esters, ketones and alcohols.

The transparent film-coated base material according to the present invention is characterized in that it is formed of a base material and a transparent film formed on the base material, and the transparent film is formed using the transparent film-forming paint described in any one of the above.

It is preferable that the content of the silica-alumina fine particles in the transparent coating film is in the range of 10 to 80 wt% as solid content and the content of the matrix component is in the range of 20 to 90 wt% as solid content.

It is preferable that the thickness of the transparent coating film is in the range of 0.5 to 20 占 퐉.

According to the present invention, it is possible to provide silica-alumina sol which is stable even at a high concentration and excellent in dispersibility into a matrix component, and a process for producing the same.

In addition, a coating film for forming a transparent film, which contains silica-alumina sol and has a low viscosity at a high concentration and is excellent in coatability and can be formed into a thick film, can be obtained.

In addition, it is an object of the present invention to provide a film forming method capable of maintaining excellent chemical resistance, water resistance, water repellency, oil repellency, and adhesion resistance to fingerprint for a long period of time with excellent adhesion to a substrate, scratch resistance, film hardness, film strength, transparency, haze, Whereby a substrate with a transparent coating film can be obtained.

[Production method of silica-alumina sol]

The method for producing silica-alumina sol according to the present invention is characterized by comprising the following steps (a) to (f).

Step (a)

(a) the silica-alumina fine particles having an average particle diameter in the range of 5 to 100 nm and an alumina content in the particles in the range of 0.01 to 5% by weight in terms of Al ₂ O ₃ have a solid concentration of 1 to 30% (Excluding H ⁺ , OH ^- ) in an amount of not more than 50 ppm in the silica-alumina fine particles with an ion exchange resin

The silica-alumina fine particle dispersion used in the present invention is not particularly limited as long as the average particle diameter of the silica-alumina fine particles and the alumina content are in the above-mentioned range, and a conventionally known silica-alumina fine particle water dispersion (hereinafter referred to as silica- ) Sol may be used.

The pH of the silica-alumina fine particle water dispersion which can be suitably used in the present invention is usually in the range of 8 to 12 alkali.

The average particle diameter of the silica-alumina fine particles is preferably in the range of 5 to 100 nm, more preferably 10 to 80 nm.

When the average particle diameter is less than 5 nm, the stability of the resulting silica-alumina sol is insufficient, and it is difficult to obtain silica / alumina sol having a high concentration, and therefore it is difficult to obtain a stable coating liquid for forming a transparent film at a high concentration .

If the average particle diameter of the silica-alumina fine particles exceeds 100 nm, the surface-negative charge amount of the silica-alumina fine particles obtained in the step (b) described later is low because of the large particle diameter, It is difficult to obtain a silica-alumina fine particle dispersion having excellent dispersibility and stability in an organic solvent, and it is also difficult to obtain a stable coating liquid for forming a transparent coating at a high concentration.

The alumina content of the silica-alumina fine particles is preferably in the range of 0.01 to 5% by weight, more preferably 0.05 to 3% by weight, in terms of Al ₂ O ₃ .

When the alumina content in the silica-alumina fine particles is less than 0.01 wt% as Al ₂ O ₃ , the surface negative charge amount of the silica-alumina fine particles obtained in the step (a) is low and the adsorption of the organosilicon compound It is difficult to obtain a dispersion of silica-alumina fine particles which is excellent in dispersibility and stability in an organic solvent.

Even when the alumina content in the silica-alumina fine particles exceeds 5 wt% as Al ₂ O ₃ , the surface negative charge amount of the silica-alumina fine particles obtained in the step (a) does not become higher, and the alkali ) And the removal of alumina, the ion exchange resin treatment efficiency is lowered.

The silica-alumina succinate is washed after production according to an ultrafiltration membrane method or an ion exchange resin method, but the alkali derived from the raw material remains in the particles and in the dispersion medium.

The residual amount of alkali is generally in the range of 1000 to 10,000 ppm even when it is present in the silica-alumina fine particles. In addition to such alkali, other cations and anions derived from raw materials, devices, etc. exist, and the total ion concentration is 1,200 to 12,000 ppm.

The concentration of the silica-alumina particulate water dispersion is not particularly limited as long as it is capable of removing a de-alkaline cation treatment by an ion exchange resin to be described later and removing the clinker ions. However, as SiO ₂ · Al ₂ O ₃ , By weight, more preferably from 2 to 25% by weight.

As the ion exchange resin, a positive ion exchange resin or a cation exchange resin and a negative ion exchange resin or both ion exchange resins are used.

A method of treating the ion exchange resin is generally a method of mixing the resin with the silica-alumina particulate water dispersion or a method of passing the silica-alumina particulate water dispersion through a column packed with the ion exchange resin.

It is preferable that the ion concentration in the silica-alumina fine particle dispersion subjected to the ion exchange resin treatment is 500 ppm or less, more preferably 250 ppm or less, even if it exists in the silica-alumina fine particles.

Here, as the ion of the ion concentration, in the cation, an alkali metal ion such as Na ⁺ , K ⁺ or the like used for the production of silica-alumina sol, an alkaline earth metal ion which exists as an impurity in the alkali metal ion, And metal ions which are eluted from the alumina sol production apparatus and incorporated therein.

Examples of the anion include chloride ions derived from hydrochloric acid and sulfuric acid ions contained in the raw materials which are mainly used for producing silica-alumina sol.

On the other hand, ions of the above ion concentration do not contain H ⁺ and OH ^- .

If the ion concentration exceeds 500 ppm in the dispersion of silica-alumina fine particles treated with the ion-exchange resin, the reason is not necessarily clear, but the adsorption amount of the organosilicon compound in the step (d) Or the ultimate concentration of silica-alumina sol to be obtained is insufficient, and even if the concentration of the silica-alumina sol can be increased, the stability tends to become insufficient.

In the present invention, the ion concentration was measured by ICP emission spectroscopy.

The step (a) is preferably composed of the following steps (a1) and (a2).

fair( a1 )

First, the dispersion is treated with a cation exchange resin such that the pH of the silica-alumina fine particle dispersion is in the range of 1.0 to 6.0, preferably 1.5 to 4.0.

When the pH of the silica-alumina fine particle dispersion after the cation exchange resin treatment is less than 1.0, alumina in the silica-alumina fine particles becomes too small, and the negative charge per unit surface area of the particles obtained in the step (a) the adsorption amount of the organosilicon compound in the step (d) becomes insufficient, so that a stable silica-alumina sol can not be obtained at a high concentration.

When the pH of the silica-alumina fine particle dispersion after the cation exchange resin treatment exceeds 6.0, the concentration of the cations (Na ions) or the clinking cations in the silica-alumina fine particles may not decrease to the above-mentioned range. Alumina sol in the step (d) of reducing the adsorption amount of the organosilicon compound to the surface of the silica-alumina fine particles is weak, the adsorption of the organosilicon compound to the surface of the silica-alumina fine particles is weak at the same time, or the silica / alumina sol finally obtained is insufficiently high- Is likely to become insufficient.

fair( a2 )

Then, the pH of the dispersion is treated with an anion exchange resin such that the pH is higher than the pH of the dispersion in the step (a1) and is in the range of 2.0 to 7.0, preferably 2.5 to 6.0.

When the pH of the silica-alumina fine particle dispersion after the anion exchange resin treatment is less than 2.0, the removal of the anion is insufficient or the surface negative charge amount described later becomes insufficient in some cases.

When the silica-alumina fine particle dispersion after the anion exchange resin treatment is subjected to the predetermined treatment in the step (a1), the pH does not exceed 7.0 and the anion concentration does not decrease further.

The negative charge amount per unit surface area of the silica-alumina fine particles of the silica-alumina fine particle water dispersion obtained in the step (a) ranges from 0.1 to 1.5 μeq / m 2, more preferably from 0.2 to 1.5 μeq / m 2 at pH 2.0 to 7.0 .

When the negative charge amount per unit surface area of the silica-alumina fine particles is less than 0.1 μeq / m 2, the adsorption amount of the organosilicon compound in the step (d) to be described later is small and the adsorption force is low. It is difficult to obtain a silica-alumina fine particle dispersion.

It is difficult to obtain a silica / alumina fine particle having a negative charge amount exceeding 1.5 mu eq / m < 2 > per unit surface area, and there is no case where the adsorption amount of the organosilicon compound increases even if it is obtained. Further, It is difficult to obtain a dispersion of fine silica-alumina fine particles at the same time.

In the present invention, the specific surface area (m 2 / g) of the particles is measured according to the BET method and the negative charge amount (μeq / g) is measured using a particle electric charge system (PCT-03 manufactured by Parent Company) By weight and a silica-alumina fine particle water dispersion having a solid content concentration of 10% by weight.

The negative charge (μeq / m 2) per unit surface area is obtained by removing the negative charge (μeq / g) from the surface area.

Step (b)

The silica-alumina particulate water dispersion is solvent-substituted with alcohol.

Here, the purpose of solvent substitution is to dissolve the organosilicon compound in the step (c) without hydrolysis, and adsorb the organosilicon compound to the silica-alumina fine particles in the step (d).

The method of solvent substitution can be changed depending on the kind of alcohol, but the ultrafiltration membrane method is preferable.

The concentration of the silica-alumina fine particle alcohol dispersion after the solvent substitution is preferably in the range of 1 to 30% by weight, more preferably 2 to 20% by weight.

On the other hand, the residual amount of water in the alcohol-silica-alumina fine particle dispersion is preferably 5% by weight or less, more preferably 1% by weight or less in the dispersion although it depends on the type and hydrolysis property of the organosilicon compound.

If the residual amount of water in the silica-alumina fine particle alcohol dispersion exceeds 5% by weight, hydrolysis in the liquid in step (c), adsorption inhibition in step (d), gelation in step (e) (f).

The measurement of the water content at this time is measured by a Karl Fischer moisture meter.

Step (c)

Subsequently, the organosilicon compound represented by the following formula (1) is added to an alcohol dispersion of silica-alumina fine particles in the presence of silica-alumina _{(4-n) / 2} as R _n -SiO Is added so as to be in the range of 1 to 50 wt%, more preferably 5 to 40 wt%, of the fine particles.

R _n -SiX _{4 -n} (1)

X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen, a hydrogen, and n is an integer of 1 to 3), R < 1 > is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms,

Examples of the organosilicon compound represented by the formula (1) include methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, Vinyltriethoxysilane, vinyltris (? Methoxyethoxy) silane, 3,3,3-trifluoropropyltriethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, vinyltrimethoxysilane, Methyl-3,3,3-trifluoropropyldimethoxysilane,? - (3,4-epoxycyclohexyl) ethyltrimethoxysilane,? -Glycidoxymethyltrimethoxysilane,? - Glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, Gamma -glycidoxypropyltriethoxysilane, gamma -glycidoxypropyltriethoxy < RTI ID = 0.0 > (Meth) acryloxymethyltrimethoxysilane,? - (? - (? - glycidoxyethoxy) propyltrimethoxysilane,? - (Meth) acryloxyethyltrimethoxysilane, gamma- (meth) acryloxyethyltriethoxysilane, gamma- (meth) acryloxypropyltrimethoxysilane, gamma- (meth) acryloxypropyltrimethoxysilane (Meth) acryloxypropyltriethoxysilane,? - (meth) acryloxypropyltriethoxysilane, butyltrimethoxysilane, isobutyltriethoxysilane, hexyltriethoxysilaoctyltrimethoxysilane, Hexyltriethoxysilane, octyltriethoxysilane, decyltriethoxysilane, 3-ureide isopropylpropyltriethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, decyltriethoxysilane, decyltriethoxysilane, butyltriethoxysilane, isobutyltriethoxysilane, Silane, perfluorooctylethyltrimethoxysilane, perfluorooctylethyltriethoxy (Aminoethyl) gamma -aminopropylmethyldimethoxysilane, N-beta (aminoethyl) gamma -aminopropyltriazine, perfluorooctylethyltriisopropoxysilane, trifluoropropyltrimethoxysilane, N- Methoxysilane, N-phenyl- gamma -aminopropyltrimethoxysilane, gamma-mercaptopropyltrimethoxysilane, trimethylsilanol, methyltrichlorosilane, and the like.

Among them, the organosilicon compound in which X in the formula (1) is an alkoxy group having 1 to 4 carbon atoms is adsorbed without easily hydrolyzing even if the amount of water remaining in the silica-alumina fine particle alcohol dispersion is in the above range And the surface treatment for enhancing the dispersibility can be efficiently performed, which is preferable.

When the addition amount of the organosilicon compound is less than 1% by weight of the silica-alumina fine particles as R _n -SiO _{(4-n) / 2} , the resulting surface treated silica-alumina fine particles have insufficient stability at high concentration and dispersibility into the matrix component .

The amount of the organosilicon compound to be added is R _n -SiO _{(4-n) / 2} which is more than 50% by weight of the silica-alumina fine particles and varies depending on the average particle diameter. However, e) may cause gelation or cause aggregation of particles in step (f). Even if adsorbed, the amount of the hydrolyzed organosilicon compound on the surface of the silica-alumina fine particles is increased and the amount thereof is increased. There are cases where the dispersibility is further improved or the concentration can not be increased.

Step (d)

Then, while stirring the silica-alumina microparticle alcohol dispersion, the organosilicon compound is adsorbed onto the silica-alumina microparticles.

The temperature of the dispersion liquid at this time is not particularly limited, but it is usually room temperature (generally 20 ° C) to below the boiling point of the alcohol solvent.

Step (e)

Water and a catalyst for hydrolysis are then added to hydrolyze the organosilicon compound.

At this time, the number of moles of water to be added (M _H2O) and the number of moles of the organic silicon compound (M _OC) with a molar ratio _{(M H2O) / (M OC} ) is 1 to 300, and further preferably in the range of 5 to 200.

When the molar ratio (M _H2O ) / (M _OC ) is less than 1, the hydrolysis becomes insufficient, the unmodified water-dispersible organosilicon compound needs to be removed, and silica-alumina sol excellent in high- It is difficult.

When the molar ratio (M _H2O ) / (M _OC ) is more than 300, it is necessary to remove it later, but it is difficult to remove it, and when it is used in a coating liquid for forming a transparent film using an organic solvent described later, stability becomes insufficient , A stable and highly concentrated coating liquid may not be obtained.

Ammonia is preferable as the catalyst for hydrolysis. If ammonia is used, it is easy to remove even if remaining in the coating liquid. If the amount of ammonia remaining is small, the stability of the coating liquid is not greatly impaired and the performance of the transparent coating formed using this coating liquid is not impaired.

The number of moles of ammonia to be added (M _NH3) and the number of moles of the organic silicon compound with a molar ratio _{(M OC) (M NH3)} / (M OC) is 0.1 to 12, and further preferably in the range of 0.2 to 10.

When the molar ratio (M _{NH 3} ) / (M _OC ) is less than 0.1, the hydrolysis becomes insufficient, the unmodified water-dispersible organosilicon compound needs to be removed, and silica-alumina sol excellent in high- It is difficult.

If the molar ratio (M _{NH 3} ) / (M _OC ) exceeds 12, the remaining unreacted water disappeared, but a large amount of ammonia remains, and the stability of the coating liquid, the performance of the transparent coating (scratch resistance, transparency, Is insufficient, and therefore, it is necessary to remove the remaining ammonia.

The method of adding water and ammonia may be separately added, but it is preferably added as ammonia water.

Step (f)

Subsequently, it is generally aged for 0.5 to 24 hours at 40 ° C to 120 ° C, particularly below the boiling point of the solvent.

By the aging under the above conditions, the hydrolysis of the organosilicon compound adsorbed on the surface of the silica-alumina fine particles is completed, the bonding reaction between the particle surface and the hydrolyzate is promoted, and silica-alumina You can get a sol.

When the negative charge amount per unit surface area of the silica-alumina fine particles of the silica-alumina fine particle water dispersion obtained in the step (f) is 0.5 to 2.0 Micro-coulombs when measured with a dispersion having a solid concentration of 0.5% by weight and a pH of 7.5 ± 1.5 / Cm < 2 >.

It is difficult to obtain the negative charge (Q ₁ ) per unit surface area of the surface-treated silica-alumina fine particles less than 0.5 micro-coulombs / cm 2, and much more than 2.0 Micro-coulombs / It may be obtained by treating the silane coupling agent with a conventionally known method without following it, and the dispersibility and stability of the organic solvent may become insufficient. A method of measuring the negative charge per unit surface area will be described later.

In the present invention, it is preferable to perform the following step (g) and / or (h) following the step (f).

Process (g)

Substitute with an organic solvent.

As the organic solvent, an organic solvent used for the coating material described later is preferable.

Specifically, it is preferably one or more selected from ethers, esters, ketones and alcohols.

With such an organic solvent, stable silica-alumina sol can be obtained at a high concentration, and furthermore, a stable coating material can be obtained at such a high concentration by using such silica-alumina sol.

The substitution with an organic solvent is not particularly limited as long as substitution is possible, but an ultrafiltration membrane method and a distillation method are generally preferred. On the other hand, at this time, it may be concentrated.

It is possible to remove residual impurities such as hydrolysis catalysts such as hydrolysis catalysts and unreacted materials and the like which can be used in the coating material of the present invention, Can be obtained.

Step (h)

Then, it is concentrated as necessary.

As the concentration method, an ultrafiltration membrane method or a distillation method may be employed in the same manner as the step (g).

On the other hand, in the present invention, either one of the steps (g) and (h) may be carried out, or both of them may be carried out.

The silica-alumina sol thus obtained preferably has a solid concentration of 20 to 70% by weight, more preferably 30 to 70% by weight.

When the solid content concentration of the silica-alumina sol is less than 20% by weight, a stable sol can be obtained without using the present invention, and a coating liquid having a high concentration can not be obtained even if it is blended with the coating liquid for forming a transparent coating film.

When the solid content concentration of the silica-alumina sol exceeds 70% by weight, it is difficult to obtain and even if it is obtained, the stability is insufficient and it is not suitable for forming a transparent coating film.

The viscosity of the silica-alumina sol is preferably from 1 to 10,000 cp, more preferably from 2 to 5,000 cp, though it varies depending on the concentration.

When the viscosity of the silica-alumina sol is less than 1 cp, it is difficult to obtain silica-alumina sol having the above concentration range. When the viscosity is more than 10,000 cp, the long-term stability is lowered and the coating property is lowered. It may be difficult to form a transparent coating excellent in scratch resistance, transparency, appearance and the like.

On the other hand, in the present invention, the viscosity can be measured by a viscometer (TOKYAN SANGYO CORPORATION: BL type viscometer).

[Silica-alumina sol]

The silica-alumina sol according to the present invention has an average particle diameter in the range of 5 to 100 nm, an alumina content in the particles in the range of 0.01 to 5% by weight in terms of Al ₂ O ₃ , (Q ₁ ) per unit surface area of the surface-treated silica-alumina fine particles and a unit surface area of the silica-alumina fine particles before being surface-treated with the organosilicon compound And the ratio (Q ₁ ) / (Q ₂ ) of the negative charge amount to the appropriate negative charge amount (Q ₂ ) is in the range of 0.2 to 0.8.

R _n -SiX _{4 -n} (1)

X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen, a hydrogen, and n is an integer of 1 to 3), R < 1 > is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms,

Surface-treated silica-alumina fine particles

In the present invention, the surface-treated silica-alumina fine particles preferably have an alumina content in the range of 0.01 to 5% by weight, more preferably 0.05 to 3% by weight, in terms of Al ₂ O ₃ .

When the alumina content in the surface-treated silica-alumina fine particles is less than 0.01% by weight in terms of Al ₂ O ₃ , the fine silica particles in the conventional silica sol, or the fine silica particles surface-treated with the conventional silane coupling agent, It is difficult to obtain a silica-alumina fine particle dispersion having a charge amount (Q ₁ ) of the same order of magnitude and excellent dispersibility and stability in an organic solvent.

Even when the alumina content in the surface-treated silica-alumina fine particles exceeds 5 wt% as Al ₂ O ₃ , the negative charge (Q ₁ ) per unit surface area is not reduced, and the dispersibility and stability to the organic solvent are larger There is no improvement.

The average particle diameter of the surface-treated silica-alumina fine particles is preferably in the range of 5 to 100 nm, more preferably 10 to 80 nm.

When the average particle diameter is less than 5 nm, the stability of the surface-treated silica-alumina fine particle dispersion is insufficient and it is difficult to obtain a silica / alumina sol having a high concentration. Therefore, obtaining a stable coating liquid for forming a transparent coating film at a high concentration It is difficult.

If the average particle diameter of the surface-treated silica-alumina fine particles exceeds 100 nm, the surface negative charge amount of the silica-alumina fine particles obtained in the step (b) is small because of the large particle diameter, It is difficult to obtain a dispersion of the surface-treated silica-alumina fine particles excellent in dispersibility and stability into an organic solvent and it is also difficult to obtain a stable coating liquid for forming a transparent coating film at a high concentration.

Suitable negative charge amount (Q ₁₎ and the ratio (Q ₁₎ / (Q ₂ of the unit of the silica-alumina particles prior to surface treatment with an organosilicon compound surface suitable negative charge amount (Q ₂₎ per unit surface of the surface-treated silica-alumina particles ) Is preferably in the range of 0.2 to 0.8, more preferably 0.2 to 0.6.

When the ratio Q ₁ / Q ₂ is less than 0.2, it is difficult to obtain. When the ratio Q ₁ / Q ₂ is more than 0.8, , And the dispersibility and stability of the organic solvent may become insufficient.

The negative charge (Q ₁ ) per unit surface area of the surface-treated silica-alumina fine particles is 0.5 to 2.0 Micro-coulombs / cm 2 when measured with a dispersion having a solid content concentration of 0.5% by weight and a pH of 7.5 ± 1.5, It is preferable that the thickness is in the range of 1.6 micro-coulombs / cm2.

It is difficult to obtain a surface-treated silica-alumina fine particle having a negative charge (Q ₁ ) of less than 0.5 micro-coulombs / cm 2, and much more than 2.0 Micro-coulombs / The silane coupling agent can be obtained by treating with a silane coupling agent by a conventionally known method, and the dispersibility and stability of the organic solvent may be insufficient.

The negative charge amount (Q ₁ ) per unit surface area of the surface-treated silica-alumina fine particles of the present invention and the negative charge amount (Q ₂ ) per unit surface area of the silica-alumina fine particles before the surface treatment with the organosilicon compound are measured, Water was added to the alumina fine particle dispersion or the silica-alumina fine particle dispersion before surface treatment with the organosilicon compound to adjust the solid content concentration to 0.5 wt% and the pH to pH 7.5 +/- 1.5, (Μeq / g) was measured using Polydialyldimethylammonium chloride of 0.001 N as a titration agent, and this was removed from the specific surface area, and at the same time, Micro- coulombs / cm < 2 >. On the other hand, the following relation was used for conversion.

1 Micro-coulombs / cm2 = 0.0628 charges / n㎡ (RALPH K.ILER, THE CHEMISTRY OF SILICA: John & Sons.

[Transparent film-forming paint]

The coating film for forming a transparent film according to the present invention comprises the silica-alumina sol, the matrix-forming component and the dispersion medium, wherein the concentration of the total solid content is in the range of 30 to 70% by weight and the concentration of the matrix- In the range of 6 to 63% by weight, and the concentration of the silica-alumina fine particles is in the range of 3 to 56% by weight.

Silica · Alumina sol

As the silica-alumina sol, silica-alumina sol and silica-alumina sol obtained by the above-mentioned production method of silica-alumina sol are used.

The matrix forming component

As the matrix forming component used in the present invention, an organic resin matrix forming component or a silicon (sol-gel) matrix forming component can be used.

As the organic resin matrix forming component, conventionally known organic resins can be used.

Specifically, known thermosetting resins, thermoplastic resins, and the like can be employed as the resin for paints. For example, a thermoplastic resin such as a polyester resin, a polycarbonate resin, a polyamide resin, a polyphenylene oxide resin, a thermoplastic acrylic resin, a vinyl chloride resin, a fluororesin, a vinyl acetate resin, A thermosetting resin such as a resin, a melamine resin, a silicon resin, a butyral resin, a reactive silicone resin, a phenol resin, an epoxy resin, an unsaturated polyester resin and a thermosetting acrylic resin.

Further, it may be a copolymer or a modified product of two or more kinds of these resins.

These resins may be emulsion resins, water-soluble resins, and hydrophilic resins. In addition, the thermosetting resin, the ultraviolet curing type, the electron beam curing type, and the thermosetting resin may include a curing catalyst.

Among them, polyfunctional acrylate resin and polyfunctional silicone resin are preferably used in the present invention. Examples of the functional group at this time include a (meth) acrylic group and an epoxy group.

Examples of the polyfunctional acrylate resin include (1) an acrylate resin having a functional group with three or more functional groups, (2) a bifunctional acrylate resin and / or a bifunctional silicone resin.

Specific examples of the acrylate resin having three or more functional groups include trifunctional acrylate resins such as pentaerythritol triacrylate, trimethylolpropane triacrylate and trimethylolpropane trimethacrylate, and pentaerythritol tetraacrylate Trifunctional urethane acrylate resins such as tetrafunctional acrylate resins such as tetrafunctional acrylate resins and dipentaerythritol hexaacrylate, and pentaerythritol hexamethylene diisocyanate urethane prepolymers, epoxy resins such as pentaerythritol polyglycidyl ether acrylate and the like Containing epoxy functional group-containing tetrafunctional acrylate resin, cresol novolak type epoxy acrylate, bisphenol A diglycidyl ether acrylic acid adduct, and the like, and mixtures thereof can also be suitably used.

The acrylate resin having three or more functional groups may be a monomer, but oligomers or polymers having a dimer or more may also be used.

Next, (2) bifunctional acrylate resins include polyethylene glycol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, polyethylene glycol dimethacrylate, neopentyl glycol Glycol acrylates such as dimethacrylate, tripropylene glycol dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, and polypropylene glycol dimethacrylate, .

In addition, it is also possible to use 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, glycerin dimethacrylate, 2hydroxy- Hexyldiol diacrylate, 1,9-nonanediol diacrylate, dimethylol-tricyclodecane diacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, and the like By weight of non-glycolic acrylate, and these mixtures can also be suitably used.

Next, as the bifunctional silicone resin, those represented by the following formula (1) are used. In the formula (1), R ₁ and R ₃ to R ₅ represent a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, X ₁ and X _{2 each} represent an acrylic group, a methacrylic group and a glycidyl group, , May be different. n is an integer of 1 to 10;

[Chemical Formula 1]

Specific examples include diacrylate-modified polysiloxane, dimethacryl-modified polysiloxane, diglycidyl-modified polysiloxane, dipolyester-modified polysiloxane, dipolyether-modified polysiloxane, and the like, and mixtures thereof.

At this time, it is preferable to use monomers for the bifunctional acrylate resin and the bifunctional silicone resin.

When the monomer is used, the combination of the acrylate resin having the above-mentioned trifunctional or higher functional group and the monofunctional silicone resin (silicone antifouling agent) described later is promoted, or the water repellency, oil repellency, (Hereinafter may be referred to as "bleed-out"), and water repellency, oil repellency, adhesion to fingerprint and chemical resistance can be maintained for a long period of time.

In addition, it is preferable to use (3) a monofunctional silicone resin represented by the following formula (2) as a silicone antifouling agent for the transparent film-forming coating material. In the formula (2), R ₁ to R ₅ represent a substituted or unsubstituted alkyl group having 1 to 3 carbon atoms, and X represents an acryl group, a methacryl group, or a glycidyl group. n is an integer of 1 to 20;

(2)

Specific examples include acrylic-modified polysiloxane, methacryl-modified polysiloxane, glycidyl-modified polysiloxane, polyester-modified polysiloxane, polyether-modified polysiloxane, and the like, and mixtures thereof. Examples thereof include (one) terminal (meth) acrylic silicone oil and one-end glycidyl silicone oil. Also suitable are acrylic-based silicone resin monomers or polymers thereof (silicone oils), epoxy-based silicone resin monomers or polymers thereof (silicone oils), polyester-based silicone resin monomers or polymers (silicone oils).

In addition, it is preferable to include a leveling agent in the transparent film-forming coating material.

As the leveling agent, polyoxyethylene tridecyl ether, polyoxyethylene lauryl ether, polyoxyalkylene lauryl ether, polyethylene isodecyl ether, polyethylene polyoxypropylene block polymer, polyoxyethylene oleate ester, polyoxyethylene distearate ester, Polyoxyethylene castor oil, and other known leveling agents and defoaming agents such as special silicones and special acrylic resins. When such a leveling agent is included, a transparent film having excellent appearance can be obtained.

Distribution dealer

The dispersion medium used in the present invention is preferably one or more kinds selected from ethers, esters, ketones and alcohols.

Specific examples thereof include alcohols such as methanol, ethanol, propanol, 2-propanol (IPA), butanol, diacetone alcohol, furfuryl alcohol and tetrahydrofurfuryl alcohol; polyhydric alcohols such as ethylene glycol and hexylene glycol; Alcohols such as methyl acetate, ethyl acetate, isopropyl acetate, isopropyl acetate, isobutyl acetate, butyl acetate, isopentyl acetate, pentyl acetate, 3-methoxybutyl acetate, 2-ethylbutyl acetate, cyclohexyl acetate, ethylene glycol mono Diethyleneglycol monoethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isopropyl ether, diethylene glycol monomethyl ether, Glycol monomethyl ether, and propylene glycol monoethyl ether; ethers such as acetone , It may be mentioned ketones such as methyl ethyl ketone, methyl isobutyl ketone, butyl methyl ketone, cyclohexanone, methyl cyclohexanone, dipropyl ketone, methyl pentyl ketone, diisobutyl ketone. These may be used alone or in combination of two or more.

polymerization Initiator

In the present invention, a polymerization initiator may be contained together with the matrix-forming component and silica-alumina fine particles. As the polymerization initiator, known ones can be used without particular limitation, and examples thereof include bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) Methyl-2-methyl-phenyl-propane-1-ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1- Phenyl-ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one.

Paint composition

It is preferable that the total solid content concentration of the transparent coating film-forming coating material is in the range of 30 to 70% by weight, and more preferably 40 to 65% by weight.

When the total solid content concentration of the coating film for forming a transparent coating film is less than 30% by weight, a stable coating liquid can be easily obtained even without using the present invention. Even if the coating film can be formed, If repeated application and drying are repeated, hardness and scratch resistance of the obtained transparent coating film become insufficient, haze or appearance deteriorates, and productivity and manufacturing reliability become poor.

When the total solid content of the coating composition for forming a transparent coating film is more than 70% by weight, the viscosity of the coating composition increases depending on the time until use, and the haze of the obtained transparent coating film becomes high or the surface roughness And the scratch resistance may become insufficient.

The concentration of the silica-alumina fine particles in the coating film for forming a transparent film is preferably in the range of 3 to 56% by weight, more preferably 6 to 39% by weight, as solid content.

When the concentration of the silica-alumina fine particles in the coating liquid for forming a transparent coating film is less than 3% by weight as solid content, the effect of blending the silica-based fine particles such as adhesion with the substrate, film strength and scratch resistance may not be obtained .

When the concentration of the silica-alumina fine particles in the coating film for forming a transparent coating film is more than 56% by weight as a solid content, the matrix component is small and the adhesion with the substrate, the film strength and the scratch resistance may become insufficient.

Next, it is preferable that the concentration of the matrix forming component in the coating film for forming a transparent coating film is in the range of 6 to 63% by weight, more preferably 16 to 55% by weight, as solid content.

Here, the matrix forming component is meant to include the polyfunctional acrylate resin, polyfunctional silicone resin, silicone-based antifouling agent and leveling agent described below.

When the concentration of the matrix forming component in the coating film for forming a transparent film is less than 6% by weight as the solid content, the adhesion to the base material, the film strength and the scratch resistance may be insufficient because the matrix component is small.

When the concentration of the matrix-forming component in the coating film for forming a transparent film is more than 63% by weight as solid content, the adhesion to the base material, the film strength and the scratch resistance may become insufficient.

It is preferable that the concentration of the above-mentioned (1) acrylate resin having a functional group having three or more functional groups in the coating film for forming a transparent film is in the range of 6 to 63% by weight, and more preferably 16 to 55% by weight.

If the concentration of the acrylate resin having three or more functional groups in the coating film for forming a transparent coating film is less than 6% by weight, the adhesion of the transparent coating film to the substrate, strength and scratch resistance may become insufficient.

When the concentration of the acrylic resin having three or more functional groups in the coating film for forming a transparent film is more than 63% by weight, 3) is small, cracks may occur in the transparent coating film, or sufficient water repellency, oil repellency, adhesion to fingerprint, etc. may not be obtained.

The concentration of the bifunctional acrylate resin and / or the bifunctional silicone resin as the solid content in the coating film for forming a transparent film is preferably in the range of 0.6 to 6.3% by weight, more preferably 1.6 to 5.5% by weight.

When the concentration of the bifunctional acrylate resin and / or the bifunctional silicone as the solid content in the coating film for forming a transparent coating film is less than 0.6% by weight, cracks may be generated in the transparent coating film or insufficient bonding with a monofunctional silicone resin The water repellency, oil repellency, adhesion of fingerprint and chemical resistance may become insufficient. In addition, the separation of the monofunctional silicone resin (sometimes referred to as "bleeding out") may occur, The chemical resistance, and the like may deteriorate over time.

Even when the concentration of the bifunctional acrylate resin and / or the bifunctional silicone as the solid content in the coating film for forming the transparent coating film exceeds 6.3 wt.%, The bonding with the monofunctional silicone resin does not increase, There is no case where the fingerprint adhesion and the chemical resistance are improved, and the elimination (bleeding-out) of the monofunctional silicone resin is not suppressed. Furthermore, the adhesion to the base material, the film strength and the like may be insufficient.

The concentration of the silicone antifouling agent in the coating film for forming a transparent film is preferably in the range of 0.003 to 0.7% by weight, more preferably 0.008 to 0.52% by weight, based on the solids content.

When the concentration of the silicone-based antifouling agent in the coating film for forming a transparent film is less than 0.003% by weight as solid content, the water repellency, oil repellency, adhesion of fingerprints and chemical resistance are insufficient depending on the film thickness of the obtained transparent coating film There is a case.

When the concentration of the silicone-based antifouling agent in the coating film for forming a transparent film exceeds 0.7% by weight as a solid content, the water repellency, oil repellency, adhesion to fingerprint and chemical resistance are not improved and adhesion to the substrate, May be insufficient.

In addition, the coating material for forming a transparent film preferably contains 0.003-0.56% by weight, more preferably 0.008-0.33% by weight, of a leveling agent as a solid content.

When the concentration of the leveling agent in the coating film for forming a transparent coating film is less than 0.003% by weight as solid content, defects or the like may occur, resulting in deterioration of the appearance of the obtained transparent coating film, and insufficient scratch resistance may not be obtained.

If the concentration of the leveling agent in the coating film for forming a transparent coating film exceeds 0.56% by weight as solid content, the appearance is not improved and the film strength may be insufficient.

The method for forming a transparent coating film using such a transparent film forming paint is applied to a substrate by a known method such as a dipping method, a spraying method, a spinner method, a roll coating method, a bar coating method, a gravure printing method, a microgravure printing method, Then, a transparent coating film can be formed by curing by a conventional method such as ultraviolet ray irradiation or heat treatment.

It is preferable that the film thickness of the obtained transparent coating film of the base material with a transparent coating film is in the range of 0.5 to 20 占 퐉.

[Apparatus with transparent coating film]

The transparent film-coated base material according to the present invention is characterized by comprising a base material and a transparent film formed on the base material, wherein the transparent film is formed using the coating liquid for forming a transparent film.

materials

As the substrate to be used in the present invention, known ones can be used without particular limitation, and plastic sheets such as glass, polycarbonate, acrylic resin, PET, and TAC, plastic films, and the like can be given. Among them, the resin base material can be suitably used.

Transparent coating

The transparent coating is composed of silica-alumina fine particles and a matrix component.

Silica-alumina fine particles

The content of the silica-alumina fine particles in the transparent coating film is preferably in the range of 10 to 80% by weight, more preferably 15 to 60% by weight, as solid content.

When the content of the silica-alumina fine particles in the transparent coating film is less than 10% by weight as solid content, the adhesion with the base material, the film strength and the scratch resistance may become insufficient.

When the content of the silica-alumina fine particles in the transparent coating film exceeds 80% by weight as solid content, the matrix component is small and the adhesion with the substrate, the film strength and the scratch resistance may become insufficient.

Matrix component

As the matrix component, the above-described silicon-based matrix component and organic resin matrix component are used. On the other hand, in the transparent coating film, the organic resin matrix forming component is cured.

The organic resin matrix component preferably contains the polyfunctional acrylate.

As the polyfunctional acrylate, the above-mentioned polyfunctional acrylate is suitably used.

Examples of the polyfunctional acrylate resin include (1) an acrylate resin having three or more functional groups, (2) a bifunctional acrylate resin and / or a bifunctional silicone resin.

The content of the matrix component in the transparent coating film is preferably in the range of 20 to 90% by weight, more preferably 40 to 85% by weight, as solid content.

When the content of the matrix component in the transparent coating film is not within the above range as the solid content, the adhesion with the substrate, the film strength and the scratch resistance may become insufficient.

It is preferable that the content of (1) the organic resin having three or more functional groups in the transparent coating film is in the range of 20 to 90% by weight, more preferably 40 to 80% by weight, as solid content.

When the content of the organic resin having three or more functional groups in the transparent coating film is less than 20% by weight as solid content, the adhesion of the transparent coating film to the substrate, strength, scratch resistance, and the like may be insufficient.

If the content of the organic resin having three or more functional groups in the transparent coating film exceeds 90% by weight as solids, the matrix components of (2) and / or (3) described below are small, Fingerprint adhesion and the like can not be obtained.

Next, it is preferable that the content of the (2) bifunctional organic resin and / or the bifunctional silicone resin in the transparent coating film is in the range of 2 to 9% by weight, more preferably 4 to 8.5% by weight, as solid content.

When the content of the (2) bifunctional organic resin and / or the bifunctional silicone resin in the transparent coating film is less than 2% by weight in terms of solid content, the bonding with the unifunctional silicone resin (3) described later is insufficient, Oil repellency, fingerprint adhesion, chemical resistance, and the like may be insufficient. In the case where a monofunctional silicone resin is contained, the monofunctional silicone resin is desorbed (sometimes referred to as "bleed out"), , Adhesion of fingerprints on the inside, chemical resistance, and the like may deteriorate over time.

Even when the content of (2) bifunctional organic resin and / or bifunctional silicone resin in the transparent coating film exceeds 9 wt% as solid content, (3) the bonding with the monofunctional silicone resin does not increase, , Oil repellency, fingerprint adhesion, chemical resistance, and the like are not improved, and the elimination (bleeding-out) of the monofunctional silicone resin is not inhibited. Furthermore, the adhesion to the base material, the film strength and the like may be insufficient.

The above-mentioned (3) monofunctional silicone resin is preferably used as the silicone antifouling agent in the transparent coating.

The content of the (3) monofunctional silicone resin (silicone antifouling agent) in the transparent coating film is preferably 0.01 to 1% by weight, more preferably 0.02 to 0.8% by weight, in terms of solid content.

When the content of the monofunctional silicone resin in the transparent coating film is less than 0.01 wt% as solid content, the water repellency, oil repellency, adhesion of fingerprint and chemical resistance may be insufficient depending on the film thickness of the transparent coating film .

When the content of the monofunctional silicone resin in the transparent coating film is more than 1% by weight as the solid content, the water repellency, oil repellency, fingerprint adhesion, chemical resistance and the like are not improved and the adhesiveness with the base film and the film strength are insufficient .

In addition, the above leveling agent can be used for the transparent coating film.

The content of the leveling agent in the transparent coating film is preferably 0.01 to 0.8% by weight, more preferably 0.02 to 0.5% by weight, in terms of solid content.

When the content of the leveling agent in the transparent coating film is less than 0.01 wt% as the solid content, defects or the like are generated depending on the film thickness of the transparent film, and the appearance of the transparent film is deteriorated. There is no case.

When the content of the leveling agent in the transparent coating film exceeds 0.8 wt% as solid content, there is no case where the appearance is further improved, and the film strength is sometimes insufficient.

The thickness of the transparent coating film is preferably in the range of 0.5 to 20 占 퐉.

When the thickness of the transparent coating film is less than 0.5 탆, sufficient scratch resistance may not be obtained.

If the thickness of the transparent coating exceeds 20 탆, shrinkage of the film may cause curling or adhesion to the substrate may be insufficient.

[ Example ]

Hereinafter, the present invention will be described in detail based on examples. However, the present invention is not limited to the scope described in these embodiments.

[Example 1]

Silica · The alumina sol (1)  pharmacy

Adding purified water to the SiO ₂ concentration of 24% by weight aqueous solution of sodium silicate as (SiO ₂ / Na ₂ O molar ratio of 3.1) to prepare a dilution (稀釋) aqueous solution of sodium silicate having a concentration of 1.2 wt% as SiO _2.

Was prepared separately, the concentration of 5% aqueous solution of sodium silicate having a weight as _{SiO 2 (SiO 2 / Na 2} O molar ratio 3.1) to de-alkali silicate solution with an acidic cation exchange resin (4.8% by weight concentration as SiO _2, pH2.8) .

Subsequently, 166 kg of an acidic silicic acid solution (concentration of 4.8% by weight as SiO ₂ , pH 2.8) was mixed with 601 kg of a dilute sodium silicate aqueous solution having a concentration of 1.2% by weight and aged at 79 캜 for 30 minutes, To prepare a dispersion.

Subsequently, 5135 kg of an acidic silicic acid solution (concentration of 4.8% by weight as SiO ₂ , pH 2.8) and 185 kg of an aqueous sodium aluminate solution having a concentration of 0.6% by weight as Al ₂ O ₃ were simultaneously stirred for 15 hours Lt; / RTI >

Subsequently, it was washed with an ultrafiltration membrane and concentrated to prepare an aqueous dispersion of silica-alumina fine particles (1) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ .

The pH of the aqueous dispersion of silica-alumina fine particles (1) was 9.1. The average particle diameter of the silica-alumina fine particles (1) was 12 nm, the Al ₂ O ₃ content was 0.10 wt%, and the Na ₂ O content was 0.5 wt%. The ion concentration was 1,500 ppm and the surface negative charge amount was 2.2 μeq / m 2 when it was present in the silica-alumina fine particles (1).

Subsequently, a cation exchange resin (SK-1BH manufactured by Mitsubishi Chemical Corporation) was added to 600 kg of an aqueous dispersion of silica-alumina fine particles (1) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ , , And then the ion exchange resin was separated. (Step (a1))

Subsequently, an anion exchange resin (product of Mitsubishi Chemical Corporation: SA-20A) was added until the pH of the dispersion became 5.0, and then the ion exchange resin was separated to obtain a solution of SiO ₂ · Al ₂ O ₃ % Aqueous dispersion of silica-alumina fine particles (1). (Step (a2))

The obtained silica-alumina fine particles (1) had a specific surface area of 260 m ₂ / g, a surface negative charge amount of 0.3 μeq / m 2, an Al ₂ O ₃ content of 0.07 wt% and an Na ₂ O content of 0.02 wt%. The ion concentration was 100 ppm even if it was present in the silica-alumina fine particles (1).

Subsequently, SiO ₂ · Al ₂ O ₃ was diluted to a concentration of 20% by weight, and then 2000 g of an aqueous dispersion of silica-alumina fine particles (1) was subjected to solvent replacement with methanol according to an ultrafiltration membrane method to obtain SiO ₂ · Al ₂ O ₃ To prepare a silica-alumina fine particle (1) alcohol dispersion having a concentration of 20% by weight. (Step (b))

The content of water in the silica-alumina fine particle (1) alcohol dispersion was 0.5% by weight.

Of silica-alumina fine particles Negative charge  Measure

(1) alcohol dispersion with a concentration of 20% by weight was diluted to a solid concentration of 0.5% by weight (at this time, the pH was 6.5), and the surface negative charges of the silica-alumina fine particles (1) were measured. Respectively.

Next, 2000 g of the silica-alumina fine particle (1) alcohol dispersion was adjusted to 25 占 폚 and γ- (meth) acryloxypropyltrimethoxysilane (manufactured by Shinetsu Kagaku Co., Ltd.: KBM- 503) ₍₃ % by weight as (M _OC ) = 0.24 mol: R ₁ -SiO _{(3) / 2} ). (Step (c))

Subsequently, the silica-alumina fine particle (1) alcohol dispersion was stirred at 25 DEG C for 0.5 hour to adsorb the organosilicon compound. (Step (d))

Subsequently, 1.5 g of ammonia water having a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M _{2 O} ) / (M _OC ) = 1.96): 0.42 g of ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Step (f))

Of surface-treated silica-alumina fine particles Negative charge  Measure

The silica-alumina fine particles (1) obtained by aging The alcohol dispersion was diluted with water to a solid concentration of 0.5% by weight. The pH of the dispersion was 7.0. The surface negative charges of the surface-treated silica-alumina fine particles (1) were measured using this dispersion, and the results are shown in the table.

Subsequently, the aged dispersion was subjected to solvent substitution with methyl isobutyl ketone by distillation and concentration to obtain a silica-alumina sol (1) having a solid content concentration of 40% by weight. (Process (g)) (Process (h))

The viscosity of the silica-alumina sol (1) was 5 cp and the stability was 5 days.

On the other hand, the stability of the sol was determined according to the following accelerated test method.

While the silica-alumina sol was kept at 90 占 폚, the time until the viscosity exceeded 10,000 cp was measured with a viscometer (TOKYAN SANGYO Co., product: BL type).

Preparation of transparent coating film-forming coating material (1)

53 g of hexafunctional acrylate resin dipentaerythritol hexaacrylate (Light Acrylate DPE-6A, manufactured by Kyoeisha Chemical Co., Ltd.) as an organic resin having three or more functional groups and 53 g of 1,6-hexanediol 5.9 g of diacrylate (KAYARAD KS-HDDA, manufactured by Nippon Kayaku Co., Ltd.) and 0.4 g of a one-terminal methacrylic silicone oil (X-22-174DX available from Shin-Etsu Chemical Co., , 75.5 g of propylene glycol monomethyl ether and 3.5 g of a photopolymerization initiator 2.4.6-trimethylbenzoyldiphenylphosphine oxide (Lucirin TPO, manufactured by BAYS Japan K.K.) to obtain a matrix-forming component having a solid content concentration of 44% by weight Solution (1) was prepared.

Subsequently, 30.0 g of the matrix-forming component solution (1) having a solid content concentration of 44% by weight and 30.0 g of the silica-alumina sol (1) surface-treated with an organic silicon compound having a solid content concentration of 40% To prepare a film-forming coating liquid (1).

The viscosity of the coating liquid for forming a transparent coating film (1) was 3 cp. The stability of the coating liquid for forming a transparent coating film (1) was 5 days. On the other hand, the stability of the coating liquid was determined according to the following accelerated test method.

The time until the viscosity exceeded 5,000 cp was measured with a viscometer (product of Toriyama Sangyo Co., Ltd.: BL type) while the coating liquid was kept at 90 占 폚.

Production of transparent film-coated substrate (1)

The coating liquid 1 for forming a transparent film was coated on this adhesive PET film (Koso Shine A-4300, thickness 188 m, total light transmittance 92.0%, haze 0.7%) with a bar coater method (bar # 12) , Dried at 80 ° C for 1 minute and then irradiated with 600 mJ / cm 2 by an ultraviolet irradiation device (Nihon Denchi product: UV irradiation device CS30L21-3) equipped with a high pressure mercury lamp (120 W / ) Was prepared. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance and haze of the obtained transparent coating film were measured by a haze meter (NDH-2000 manufactured by Nippon Denshoku Co., Ltd.), and the results are shown in the table.

In addition, the pencil hardness, scratch resistance and adhesion were evaluated by the following methods and evaluation criteria, and the results are shown in the table.

Measurement of pencil hardness

And measured by a pencil hardness tester in accordance with JIS-K-5400.

On the other hand, since the coating film for forming a transparent film of the present invention is a stable coating solution even at a high concentration, destabilization of the formed film can be suppressed even when exposed to a high temperature in the drying step and a dense transparent film can be formed, Can be obtained. That is, the pencil hardness can be an index of the stability of the paint.

Abrasive  Measure

# 0000 steel wool at a load of 500 g / cm < 2 > for 50 times, and the surface of the film was visually observed and evaluated according to the following criteria, and the results are shown in the table.

I can not recognize the wound of 筋 条: ◎

A few scratches are recognized in the fingers: ○

A lot of wounds are recognized at the end of the day: △

The face is entirely trimmed: x

Adhesiveness

The surface of the transparent film-adhered substrate 1 was coated with 11 parallel wounds at intervals of 1 mm in the longitudinal and transverse directions with a knife to make 100 squares, a cellophane tape (registered trademark) was adhered thereto, and then a cellophane tape ) Was peeled off, the adhesion was evaluated by classifying the number of grits remaining without peeling the coating into the following four levels. The results are displayed in the table.

95 or more remaining grids: ◎

Number of remaining grids 90-94: ○

Number of remaining grids 85-89: △

Number of remaining grids 84 or less: x

Exterior

With respect to the transparent film-coated substrate (1), skip and film unevenness were visually observed and evaluated according to the following criteria.

No skipping or film smudges are recognized: ◎

Slight skip and film smudges are recognized: ○

Bounces and film stains are clearly recognized: △

Many skipping and film spots are recognized: x

[Example 2]

Silica · The alumina sol (2)  pharmacy

A seed dispersion was prepared in the same manner as in Example 1.

Then, 5042.5 kg of an acidic silicic acid solution (concentration of 4.8 wt% as SiO ₂ , pH 2.8) and 924.3 kg of an aqueous sodium aluminate solution having a concentration of 0.6 wt% as Al ₂ O ₃ were simultaneously stirred for 15 hours Lt; / RTI >

Subsequently, it was washed with an ultrafiltration membrane and concentrated to prepare an aqueous dispersion of silica-alumina fine particles (2) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ .

The pH of the aqueous dispersion of silica-alumina fine particles (2) was 9.1. The average particle diameter of the silica-alumina fine particles (2) was 12 nm, the Al ₂ O ₃ content was 0.50 wt%, and the Na ₂ O content was 0.5 wt%. The ion concentration was 1,550 ppm and the surface negative charge amount was 2.8 mu eq / m < 2 > when it was present in the silica-alumina fine particles (2).

Then, SiO _2, Al ₂ O ₃ concentration of 30% by weight in terms of silica of the alumina fine particles, (2) an aqueous dispersion 600㎏ a cation exchange resin (Mitsubishi Chemical Co., Ltd. product: SK-1BH) is a dispersion of a pH of 2.0 , And then the ion exchange resin was separated. (Step (a1))

Subsequently, an anion exchange resin (product of Mitsubishi Chemical Corporation: SA-20A) was added until the pH of the dispersion became 5.0, and then the ion exchange resin was separated, and a SiO ₂ · Al ₂ O ₃ concentration of 27 wt% % Aqueous dispersion of silica-alumina fine particles (2). (Step (a2))

The obtained silica-alumina fine particles (1) had a specific surface area of 269 m ₂ / g, a surface negative charge amount of 0.6 μeq / m 2, an Al ₂ O ₃ content of 0.41 wt% and an Na ₂ O content of 0.04 wt%. The ion concentration was 120 ppm in the silica-alumina fine particles (1).

Subsequently, SiO ₂ · Al ₂ O ₃ was diluted to a concentration of 20% by weight, and then 2000 g of an aqueous dispersion of silica-alumina fine particles (2) was subjected to solvent substitution by methanol in accordance with an ultrafiltration membrane method to obtain SiO _{2 ·} Al ₂ O ₃ To prepare a silica-alumina fine particle (2) alcohol dispersion having a concentration of 20% by weight. (Step (b))

The content of water in the silica-alumina fine particle (2) alcohol dispersion was 0.5% by weight.

The surface negative charge amount of the silica-alumina fine particles (2) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica-alumina fine particle (2) alcohol dispersion was adjusted to 25 占 폚 and γ- (meth) acryloxypropyltrimethoxysilane (manufactured by Shinetsu Kagaku Co., Ltd.: KBM- 503) ₍₃ % by weight as (M _OC ) = 0.24 mol: R ₁ -SiO _{(3) / 2} ). (Step (c))

Subsequently, the silica-alumina fine particle (2) alcohol dispersion was stirred at 25 DEG C for 0.5 hour to adsorb the organosilicon compound. (Step (d))

Subsequently, 1.5 g of ammonia water having a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M ₂ H _{2 O} ) / (M _OC ) were added to the silica / alumina fine particle (2) (Molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Step (f))

Subsequently, the surface negative charges of the surface-treated silica-alumina fine particles (2) were measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was carried out to prepare a silica-alumina sol (2) having a solid content concentration of 40% by weight. (Process (g)) (Process (h))

The viscosity of the silica-alumina sol (2) was 5 cp and the stability was 6 days.

Preparation of transparent coating film-forming coating material (2)

A coating liquid (2) for forming a transparent coating film having a solid content concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (2) having a solid content concentration of 40% by weight was used.

The viscosity of the coating liquid 2 for forming a transparent coating film was 5 cp and the stability was 5 days.

Production of transparent film-coated substrate (2)

A transparent film-coated base material (2) was prepared in the same manner as in Example 1 except that the coating liquid (2) for forming a transparent film was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Example 3]

Silica · The alumina sol (3)  pharmacy

A seed dispersion was prepared in the same manner as in Example 1.

Subsequently, 4580 kg of an acidic silicic acid solution (concentration of 4.8 wt% as SiO ₂ , pH 2.8) and 4621.7 kg of an aqueous sodium aluminate solution having a concentration of 0.6 wt% as Al ₂ O ₃ were simultaneously stirred for 15 hours Lt; / RTI >

Subsequently, it was washed with an ultrafiltration membrane and concentrated to prepare an aqueous dispersion of silica-alumina fine particles (3) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ .

The pH of the aqueous dispersion of silica-alumina fine particles (3) was 9.1. The average particle diameter of the silica-alumina fine particles (3) was 13 nm, the Al ₂ O ₃ content was 2.50 wt%, and the Na ₂ O content was 0.6 wt%. The ion concentration was 1700 ppm and the surface negative charge amount was 3.1 mu eq / m < 2 > when it was present in the silica-alumina fine particles (3).

Subsequently, a cation exchange resin (SK-1BH manufactured by Mitsubishi Chemical Corporation) was added to 600 kg of an aqueous dispersion of silica-alumina fine particles (3) having a concentration of 30% by weight as SiO ₂ · Al ₂ O ₃ , , And then the ion exchange resin was separated. (Step (a1))

Subsequently, an anion exchange resin (product of Mitsubishi Chemical Corporation: SA-20A) was added until the pH of the dispersion became 5.0, and then the ion exchange resin was separated to obtain a solution of SiO ₂ · Al ₂ O ₃ % Aqueous dispersion of silica-alumina fine particles (3). (Step (a2))

The obtained silica-alumina fine particles (3) had a specific surface area of 282 m ₂ / g, a surface negative charge amount of 0.8 μeq / m 2, an Al ₂ O ₃ content of 1.9 wt% and an Na ₂ O content of 0.05 wt%. The ion concentration was 115 ppm in the silica-alumina fine particles (3).

Subsequently, SiO ₂ .Al ₂ O ₃ was diluted to a concentration of 20 wt%, and then 2000 g of an aqueous dispersion of silica-alumina fine particles (3) was subjected to solvent substitution by methanol in accordance with an ultrafiltration membrane method to obtain SiO ₂ · Al ₂ O ₃ A silica-alumina fine particle (3) alcohol dispersion having a concentration of 20% by weight was prepared. (Step (b))

The content of water in the silica-alumina fine particle (3) alcohol dispersion was 0.5% by weight.

The surface negative charge amount of the silica-alumina fine particles (3) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica-alumina fine particle (3) alcohol dispersion was adjusted to 25 占 폚 and γ- (meth) acryloxypropyltrimethoxysilane (KBM- 503) ₍₃ % by weight as (M _OC ) = 0.24 mol: R ₁ -SiO _{(3) / 2} ). (Step (c))

Subsequently, the silica-alumina fine particle (3) alcohol dispersion was stirred at 25 DEG C for 0.5 hours to adsorb the organosilicon compound. (Step (d))

Subsequently, 1.5 g of ammonia water having a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M ₂ H _{2 O} ) / (M _OC ) were added to the silica / alumina fine particle (3) (Step (e)): 0.42 g of ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Step (f))

Subsequently, the surface negative charges of the surface-treated silica-alumina fine particles (3) were measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was carried out to prepare a silica-alumina sol (3) having a solid content concentration of 40% by weight. (Process (g)) (Process (h))

The viscosity of the silica-alumina sol (3) was 7 cp and the stability was 6.5 days.

The preparation of the transparent film-forming paint (3)

A coating liquid (3) for forming a transparent coating film having a solid content concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (3) having a solid concentration of 40% by weight was used.

The viscosity of the coating liquid 3 for forming a transparent coating film was 8 cp and the stability was 6 days.

Production of transparent film-coated substrate (3)

A transparent film-coated base material (3) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent film (3) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Example 4]

Silica · The alumina sol (4)  pharmacy

A seed dispersion was prepared in the same manner as in Example 1.

Subsequently, 25,650 kg of an acidic silicic acid solution (concentration of 4.8 wt% as SiO ₂ , pH 2.8) and 919 kg of an aqueous sodium aluminate solution having a concentration of 0.6 wt% as Al ₂ O ₃ were simultaneously stirred for 15 hours Lt; / RTI >

Subsequently, it was washed with an ultrafiltration membrane and concentrated to prepare an aqueous dispersion of silica-alumina fine particles (4) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ .

The pH of the aqueous dispersion of silica-alumina fine particles (4) was 9.1. The average particle diameter of the silica-alumina fine particles (4) was 25 nm, the Al ₂ O ₃ content was 0.10 wt%, and the Na ₂ O content was 0.9 wt%. The ion concentration was 2400 ppm and the surface negative charge amount was 3.3 μeq / m 2 when it was present in the silica-alumina fine particles (4).

Subsequently, a cation exchange resin (SK-1BH manufactured by Mitsubishi Chemical Corporation) was added to 600 kg of an aqueous dispersion of silica-alumina fine particles (4) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ , , And then the ion exchange resin was separated. (Step (a1))

Subsequently, an anion exchange resin (product of Mitsubishi Chemical Corporation: SA-20A) was added until the pH of the dispersion became 5.0, and then the ion exchange resin was separated to obtain a solution of SiO ₂ · Al ₂ O ₃ % Aqueous dispersion of silica-alumina fine particles (4). (Step (a2))

The obtained silica-alumina fine particles (4) had a specific surface area of 120 m ₂ / g, a surface negative charge amount of 0.2 μeq / m 2, an Al ₂ O ₃ content of 0.07 wt% and an Na ₂ O content of 0.02 wt%. The ion concentration was 230 ppm in the silica-alumina fine particles (4).

Subsequently, SiO ₂ · Al ₂ O ₃ was diluted to a concentration of 20 wt%, and then 2000 g of an aqueous dispersion of silica-alumina fine particles (4) was subjected to solvent substitution by methanol in accordance with an ultrafiltration membrane method to obtain SiO ₂ · Al ₂ O ₃ To prepare a silica-alumina fine particle (4) alcohol dispersion having a concentration of 20% by weight. (Step (b))

The content of water in the silica-alumina fine particle (4) alcohol dispersion was 0.5% by weight.

The surface negative charge amount of the silica-alumina fine particles (4) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica-alumina fine particle (4) alcohol dispersion was adjusted to 25 占 폚 and γ- (meth) acryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.: KBM- 503) ₍₃ % by weight as (M _OC ) = 0.24 mol: R ₁ -SiO _{(3) / 2} ). (Step (c))

Subsequently, the silica-alumina fine particle (4) alcohol dispersion was stirred at 25 DEG C for 0.5 hours to adsorb the organosilicon compound. (Step (d))

Subsequently, 1.5 g of ammonia water having a concentration of 28 wt% as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M ₂ H _{2 O} ) / (M _OC ) were added to the silica / alumina fine particle (4) alcohol dispersion, = 1.96): 0.42 g of ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Step (f))

Subsequently, the surface negative charges of the surface-treated silica-alumina fine particles (4) were measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was carried out to prepare a silica-alumina sol (4) having a solid content concentration of 40% by weight. (Process (g)) (Process (h))

The viscosity of the silica-alumina sol (4) was 17 cp and the stability was 4 days.

Preparation of the transparent film-forming coating material (4)

A coating liquid (4) for forming a transparent coating film having a solid concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (4) having a solid content concentration of 40% by weight was used.

The viscosity of the coating liquid 4 for forming a transparent coating film was 20 cp and the stability was 5 days.

Production of transparent film-coated substrate (4)

A transparent film-coated base material (4) was prepared in the same manner as in Example 1 except that the coating liquid for transparent film formation (4) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Example 5]

Silica · Alumina sol (5)  pharmacy

A seed dispersion was prepared in the same manner as in Example 1.

Subsequently, 205,200 kg of an acidic silicic acid solution (concentration of 4.8% by weight as SiO ₂ , pH 2.8) and 7,354 kg of an aqueous sodium aluminate solution having a concentration of 0.6% by weight as Al ₂ O ₃ were simultaneously added thereto for 15 hours Lt; / RTI >

Subsequently, it was washed with an ultrafiltration membrane and concentrated to prepare an aqueous dispersion of silica-alumina fine particles (5) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ .

The pH of the aqueous dispersion of silica-alumina fine particles (5) was 9.1. The average particle diameter of the silica-alumina fine particles (5) was 45 nm, the Al ₂ O ₃ content was 0.10 wt%, and the Na ₂ O content was 1.2 wt%. The ion concentration was 3,600 ppm and the surface negative charge amount was 3.4 占 q / m2, assuming that it was present in the silica-alumina fine particles (5).

Subsequently, a cation exchange resin (SK-1BH manufactured by Mitsubishi Chemical Corporation) was added to 600 kg of an aqueous dispersion of silica-alumina fine particles (5) having a concentration of 30% by weight as SiO ₂ .Al ₂ O ₃ , , And then the ion exchange resin was separated. (Step (a1))

Subsequently, an anion exchange resin (product of Mitsubishi Chemical Corporation: SA-20A) was added until the pH of the dispersion became 5.0, and then the ion exchange resin was separated to obtain a solution of SiO ₂ · Al ₂ O ₃ % Aqueous dispersion of silica-alumina fine particles (5). (Step (a2))

The obtained silica-alumina fine particles (5) had a specific surface area of 68 m ₂ / g, a surface negative charge amount of 0.1 μeq / m 2, an Al ₂ O ₃ content of 0.09 wt% and an Na ₂ O content of 0.23 wt%. The ion concentration was 380 ppm in the silica-alumina fine particles (5).

Subsequently, after diluting with SiO ₂ .Al ₂ O _{3 to} a concentration of 20% by weight, 2000 g of an aqueous dispersion of silica-alumina fine particles (5) was subjected to solvent substitution with methanol in accordance with an ultrafiltration membrane method to obtain SiO ₂ · Al ₂ O ₃ A silica-alumina fine particle (5) alcohol dispersion having a concentration of 20% by weight was prepared. (Step (b))

The content of water in the silica-alumina fine particle (5) alcohol dispersion was 0.5% by weight.

The surface negative charge amount of the silica-alumina fine particles (5) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica-alumina fine particle (5) alcohol dispersion was adjusted to 25 占 폚 and γ- (meth) acryloxypropyltrimethoxysilane (manufactured by Shinetsu Kagaku Co., Ltd.: KBM- 503) ₍₃ % by weight as (M _OC ) = 0.24 mol: R ₁ -SiO _{(3) / 2} ). (Step (c))

Subsequently, the silica-alumina fine particle (5) alcohol dispersion was stirred at 25 DEG C for 0.5 hour to adsorb the organosilicon compound. (Step (d))

Subsequently, 1.5 g of ammonia water having a concentration of 28 wt% as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M _H2O ) / (M _OC ) were added to the silica / alumina fine particle (5) (Step (e)): 0.42 g of ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Step (f))

Subsequently, the surface negative charges of the surface-treated silica-alumina fine particles (5) were measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was carried out to prepare a silica-alumina sol (5) having a solid content concentration of 40% by weight. (Process (g)) (Process (h))

The silica-alumina sol (5) had a viscosity of 25 cp and a stability of 3 days.

Preparation of the transparent film-forming paint (5)

A coating liquid 5 for forming a transparent coating film having a solid concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (5) having a solid content concentration of 40% by weight was used.

The viscosity of the coating liquid 5 for forming a transparent coating film was 32 cp and the stability was 5 days.

Production of transparent film-coated substrate (5)

A transparent film-coated base material (5) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent film (5) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Example 6]

Silica · Alumina sol (6)  pharmacy

In Example 1, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was conducted to prepare a silica-alumina sol (6) having a solid concentration of 60% by weight. (Process (g)) (Process (h))

The viscosity of the silica-alumina sol (6) was 120 cp and the stability was 3 days.

Preparation of the transparent coating film-forming coating material (6)

53 g of tetrafunctional acrylate resin pentaerythritol tetraacrylate (manufactured by Kyoeisha Chemical Co., Ltd., light acrylate PE-4A) as an organic resin having three or more functional groups and 1,6-hexanediol di (KAYARAD KS-HDDA, manufactured by Nippon Kayaku Co., Ltd.) and 0.4 g of a one-terminal methacrylic silicone oil (X-22-174DX available from Shin-Etsu Chemical Co., Ltd.) as a monofunctional silicone resin , 33.4 g of propylene glycol monomethyl ether and 3.5 g of a photopolymerization initiator 2.4.6-trimethylbenzoyldiphenylphosphine oxide (Lucirin TPO, manufactured by BAYES Japan K.K.) to obtain a matrix forming component solution having a solid content concentration of 64% by weight (2) was prepared.

Subsequently, 30.0 g of the matrix-forming component solution (2) having a solid content concentration of 64% by weight and 30.0 g of the silica-alumina sol (6) surface-treated with an organosilicon compound having a solid content concentration of 60% To thereby prepare a film-forming coating liquid (6).

The coating liquid 6 for forming a transparent coating film had a viscosity of 110 cp and a stability of 3 days.

Production of transparent film-coated substrate (6)

Coating liquid 6 for forming a transparent coating film was coated on this adhesive PET film (Cosmo Shine A-4300, thickness 188 m, total light transmittance 92.0%, haze 0.7%) with a bar coater method (bar # 10) , Dried at 80 ° C for 1 minute and then irradiated with 600 mJ / cm 2 by an ultraviolet irradiation device (Nihon Denchi product: UV irradiation device CS30L21-3) equipped with a high pressure mercury lamp (120 W / cm) ) Was prepared. The thickness of the transparent coating at this time was 5 占 퐉.

[Example 7]

Silica · Alumina sol (7)  pharmacy

In Example 1, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was conducted to prepare silica-alumina sol (7) having a solid concentration of 70 wt%. (Process (g)) (Process (h))

The viscosity of the silica-alumina sol (7) was 780 cp and the stability was 2 days.

Preparation of the transparent film-forming paint (7)

53 g of hexafunctional acrylate resin dipentaerythritol hexaacrylate (Light Acrylate DPE-6A, manufactured by Kyoeisha Chemical Co., Ltd.) as an organic resin having three or more functional groups and 1,6-hexanediol di (KAYARAD KS-HDDA, manufactured by Nippon Kayaku Co., Ltd.) and 0.4 g of a one-terminal methacrylic silicone oil (X-22-174DX available from Shin-Etsu Chemical Co., Ltd.) as a monofunctional silicone resin , 25.4 of propylene glycol monomethyl ether and 3.5 g of a photopolymerization initiator 2.4.6-trimethylbenzoyldiphenylphosphine oxide (Lucirin TPO, manufactured by BAYES Japan K.K.) to obtain a matrix-forming component solution (solid content concentration: 3) was prepared.

Subsequently, 30.0 g of the matrix-forming component solution (3) having a solid content concentration of 74 wt% and 30.0 g of the silica-alumina sol (7) surface-treated with an organic silicon compound having a solid concentration of 70 wt% were mixed to prepare a transparent To prepare a film-forming coating liquid (7).

The viscosity of the coating liquid 7 for forming a transparent coating film was 960 cp and the stability was 1 day.

Production of transparent film-coated substrate (7)

The coating liquid 7 for forming a transparent film was coated on this adhesive PET film (Cosmo Shine A-4300, thickness 188 m, total light transmittance 92.0%, haze 0.7%) using a bar coater method (Bar # 9) , Dried at 80 ° C for 1 minute and irradiated with 600 mJ / cm 2 by an ultraviolet irradiation device (Nihon Denchi product: UV irradiation device CS30L21-3) equipped with a high pressure mercury lamp (120 W / cm) ) Was prepared. The thickness of the transparent coating at this time was 5 占 퐉.

[Example 8]

Preparation of the transparent film-forming paint (8)

In the same manner as in Example 1 except that 0.2 g of a special silicone leveling agent (Disparlon # 1711 manufactured by Cusmotocase Co., Ltd.) was used as a leveling agent, the matrix forming component solution 4 having a solid concentration of 44 wt% Was prepared.

Subsequently, 30.0 g of the matrix-forming component solution (4) having a solid content concentration of 44% by weight and 30.0 g of the silica-alumina sol (1) surface-treated with the organosilicon compound having a solid concentration of 40% by weight prepared in the same manner as in Example 1 To prepare a coating liquid (8) for forming a transparent coating film having a solid content concentration of 42% by weight.

The viscosity of the coating liquid for forming a transparent coating film 8 was 3 cp. The stability of the coating liquid for forming a transparent coating film (8) was 5 days.

Production of transparent film-coated substrate (8)

A transparent film-coated base material (8) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent film (8) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Comparative Example 1]

Silica · Alumina sol (R1)  pharmacy

In the same manner as in Example 1, an aqueous dispersion of silica-alumina fine particles (1) having a concentration of 30% by weight was prepared as SiO ₂ · Al ₂ O ₃ used as a raw material after being washed with an ultrafiltration membrane.

Subsequently, SiO ₂ · Al ₂ O ₃ was diluted to a concentration of 20% by weight, and then 2000 g of an aqueous dispersion of silica-alumina fine particles (1) was subjected to solvent replacement with methanol according to an ultrafiltration membrane method to obtain SiO ₂ · Al ₂ O ₃ A silica-alumina fine particle (R1) alcohol dispersion having a concentration of 10% by weight was prepared. (Equivalent to process (b)).

The content of water in the silica-alumina fine particle (R1) alcohol dispersion was 0.8% by weight.

The surface negative charge amount of the silica-alumina fine particles (R1) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica-alumina fine particle (R1) alcohol dispersion was adjusted to 25 占 폚 and γ- (meth) acryloxypropyltrimethoxysilane (manufactured by Shinetsu Kagaku Co., Ltd.: KBM- 503) ₍₃ % by weight as (M _OC ) = 0.24 mol: R ₁ -SiO _{(3) / 2} ). (Equivalent to step (c)).

Subsequently, the silica-alumina fine particle (R1) alcohol dispersion was stirred at 25 DEG C for 0.5 hour to adsorb the organosilicon compound. (Equivalent to step (d)).

Subsequently, 1.5 g of ammonia water having a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M _H2O ) / (M _OC ) were added to an alumina dispersion of silica- = 1.96): 0.42 g of ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Equivalent to process (f)).

Subsequently, the surface negative charges of the surface-treated silica-alumina fine particles (R1) were measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was conducted to prepare a silica-alumina sol (R1) having a solid content concentration of 40% by weight. (Equivalent to step (g)) (equivalent to step (h)

The viscosity of the silica-alumina sol (R1) was 240 cp and the stability was 0.5 day.

Coating for forming a transparent film ( R1 ) Preparation

A coating liquid R1 for forming a transparent coating film having a solid concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (R1) having a solid concentration of 20% by weight was used.

The viscosity of the coating liquid R1 for forming a transparent coating film was 360 cp, and the stability was 0.5 day.

A transparent film-adhered substrate ( R1 )

A transparent film-coated substrate (R1) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent coating (R1) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Comparative Example 2]

Silica · The alumina sol (R2)  pharmacy

In Comparative Example 1, as an organic silicon compound as γ- (meth) acryloxy propyl trimethoxy silane (manufactured by Shin-Etsu Chemical Co., Ltd. product: KBM-503) 120g (( M OC) = 0.48 mole: R ₁ -SiO _{(3) / 2} , 6% by weight)) was added. (Equivalent to step (c)).

Subsequently, 1.5 g of ammonia water at a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M _{2 O} ) / (M _OC ) = 1.00) _NH3) = 0.025, yielding a molar ratio (M _NH3)) / (M _OC) was added to = 0.05) (step (e)) other than the same, and a solid content of 40% by weight of silica-alumina sol (R2). (Step (g)) (equivalent to step (h))

The viscosity of the silica-alumina sol (R2) was 120 cp and the stability was 1 day.

On the other hand, after the step (f), the surface negative charges of the surface-treated silica-alumina fine particles (R2) were measured in the same manner as in Example 1, and the results are shown in the table.

Coating for forming a transparent film ( R2 ) Preparation

A coating liquid (R2) for forming a transparent coating film having a solid content concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (R2) having a solid concentration of 40% by weight was used.

The viscosity of the coating liquid for forming a transparent coating film R2 was 230 cp and the stability was 1 day.

A transparent film-adhered substrate ( R2 )

A transparent film-coated base material (R2) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent film (R2) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Comparative Example 3]

Silica · The alumina sol (R3)  pharmacy

The silica-alumina sol (R3) having a solid concentration of 40% by weight was prepared in the same manner as in Example 1 except that the step (c) was followed immediately (step (e)).

The silica-alumina sol (R3) had a viscosity of 8 cp and a stability of 4 days.

On the other hand, after the step (f), the surface negative charges of the surface-treated silica-alumina fine particles (R3) were measured in the same manner as in Example 1, and the results are shown in the table.

Coating for forming a transparent film ( R3 ) Preparation

A coating liquid (R3) for forming a transparent coating film having a solid concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (R3) having a solid concentration of 40% by weight was used.

The viscosity of the coating liquid for forming a transparent coating film (R3) was 5 cp and the stability was 3 days.

A transparent film-adhered substrate ( R3 )

A transparent film-coated base material (R3) was prepared in the same manner as in Example 1 except that the coating liquid (R3) for forming a transparent coating film was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Comparative Example 4]

Of the silica organosols (R4)  pharmacy

The silica sol (CATALOID SI-30, average particle diameter: 12 nm, SiO ₂ concentration: 30 wt%, Al ₂ O ₃ content: 0 wt%, Na ₂ O content: 0.4 wt% %, PH: 9.3, ion concentration: 1300 ppm in the presence of silica fine particles and surface negative charge: 1.9 μeq / m 2) was diluted as SiO _{2 to} a concentration of 20% by weight and then 2000 g of a silica fine particle water dispersion was subjected to ultrafiltration , And the solvent was replaced with methanol to prepare a silica fine particle (R4) alcohol dispersion having a concentration of 20% by weight as SiO ₂ . (Equivalent to process (b)).

The content of water in the silica fine particle (R4) alcohol dispersion was 0.5% by weight.

The surface negative charge amount of the fine silica particles (R4) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica fine particle (R4) alcohol dispersion was adjusted to 25 캜 and γ- (meth) acryloxypropyltrimethoxysilane (KBM-503, Shin-Etsu Chemical Co., Ltd.) and further _{a): 60g (R 1 -SiO (} 3) 3 % by weight in terms of _{/ 2} (M _OC) = 0.24 mole). (Equivalent to step (c)).

Subsequently, the silica fine particle (R4) alcohol dispersion was stirred at 25 占 폚 for 0.5 hour to adsorb the organosilicon compound. (Equivalent to step (d)).

Subsequently, 1.5 g of ammonia water having a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M ₂ H _{2 O} ) / (M _OC ) = 1.96 ): Ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Equivalent to process (f)).

Subsequently, the surface negative charge amount of the surface-treated silica fine particles (R4) was measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was conducted to prepare a silica sol (R4) having a solid content concentration of 40% by weight. (Step (g)) (equivalent to step (h))

The viscosity of the silica sol (R4) was 360 cp and the stability was 0.5 days.

Coating for forming a transparent film ( R4 ) Preparation

A coating liquid (R4) for forming a transparent coating film having a solid concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (R4) having a solid content concentration of 40% by weight was used.

The viscosity of the coating liquid R4 for forming a transparent coating film was 450 cp and the stability was 0.5 day.

A transparent film-adhered substrate ( R4 )

A transparent film-coated substrate (R4) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent film (R4) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

[Comparative Example 5]

Of the silica organosol (R5)  pharmacy

The silica sol (CATALOID SI-30, average particle diameter: 12 nm, SiO ₂ concentration: 30 wt%, Al ₂ O ₃ content: 0 wt%, Na ₂ O content: 0.4 wt% And the surface negative charge amount was 1.9 占 q ec / m2) was diluted with SiO _{2 to} a concentration of 20% by weight, and then 600 kg of a silica fine particle (R5) water dispersion was added with a cation Exchange resin (product of Mitsubishi Chemical Corporation: SK-1BH) was added until the pH of the dispersion became 2.0, and then the ion-exchange resin was separated. (Equivalent to the step (al)

Then, the anion exchange resin (Mitsubishi Chemical Co., Ltd. product: SA-20A) and the addition until the pH of the dispersion is 5.0, then the ion separating exchange resin, silica fine particles having a concentration of 27% by weight in terms of SiO ₂ ( R5) water dispersion was prepared. (Equivalent to the step (a2)

The obtained fine silica particles (R5) had a specific surface area of 251 m ₂ / g, a surface negative charge amount of 0.1 μeq / m 2, an Al ₂ O ₃ content of 0 wt% and an Na ₂ O content of 0.02 wt%. The ion concentration was 110 ppm in terms of the amount of the silica fine particles (R5).

Then, after the silica fine particles (R5) dispersion 2000g an ultrafiltration membrane method, a displacement, the silica fine particles (R5) the alcohol dispersion of a concentration of 20% by weight in terms of SiO ₂ the solvent with methanol in accordance with the dilution as SiO ₂ at a concentration of 20% by weight Was prepared. (Equivalent to process (b)).

The water content in the silica fine particle (R5) alcohol dispersion was 0.5% by weight.

The surface negative charge amount of the fine silica particles (R5) was measured in the same manner as in Example 1, and the results are shown in the table.

Next, 2000 g of the silica fine particle (R5) alcohol dispersion was adjusted to 25 占 폚, and γ- (meth) acryloxypropyltrimethoxysilane (KBM-503 manufactured by Shin-Etsu Chemical Co., and further _{a): 60g (R 1 -SiO (} 3) 3 % by weight in terms of _{/ 2} (M _OC) = 0.24 mole). (Equivalent to step (c)).

Subsequently, the silica fine particle (R5) alcohol dispersion was stirred at 25 DEG C for 0.5 hour to adsorb the organosilicon compound. (Equivalent to step (d)).

Subsequently, 1.5 g of ammonia water having a concentration of 28% by weight as ammonia and 7.8 g of pure water (8.78 g of water (M _H2O ) = 0.49, molar ratio (M ₂ H _{2 O} ) / (M _OC ) = 1.96 ): Ammonia (molar ratio (M _{NH 3} ) = 0.025, molar ratio (M _{NH 3} ) / (M _OC ) = 0.1)

The dispersion was then adjusted to 50 DEG C and aged for 19 hours. (Equivalent to process (f)).

Subsequently, the surface negative charge amount of the surface-treated silica fine particles (R5) was measured in the same manner as in Example 1, and the results are shown in the table.

Subsequently, the solvent was replaced with methyl isobutyl ketone by distillation and concentration was carried out to prepare a silica sol (R5) having a solid content concentration of 40% by weight. (Step (g)) (equivalent to step (h))

The viscosity of the silica sol (R5) was 8 cp and the stability was 4 days.

Coating for forming a transparent film ( R5 ) Preparation

A coating liquid for forming a transparent coating film (R5) having a solid concentration of 42% by weight was prepared in the same manner as in Example 1 except that the silica-alumina sol (R5) having a solid concentration of 40% by weight was used.

The viscosity of the coating liquid for forming a transparent coating film (R5) was 12 cp and the stability was 4 days.

A transparent film-adhered substrate ( R5 )

A transparent-film-adhered base material (R5) was prepared in the same manner as in Example 1 except that the coating liquid for forming a transparent coating (R5) was used. The thickness of the transparent coating at this time was 5 占 퐉.

The total light transmittance, haze, pencil hardness, scratch resistance and adhesion of the obtained transparent coating film were measured, and the results are shown in the table.

Claims (19)

A process for producing silica-alumina sol containing silica-alumina fine particles having an alumina content of 0.01 to 5% by weight as Al ₂ O ₃ ,
(a) an aqueous dispersion in which silica-alumina fine particles having an average particle diameter of 5 to 100 nm and an alumina content in particles of 0.01 to 5 wt% as Al ₂ O ₃ are dispersed in a solid concentration of 1 to 30 wt% , Treating the aqueous dispersion with an ion-exchange resin so that the concentration of the ion (excluding H ⁺ , OH ^- ) in the aqueous dispersion becomes 500 ppm or less in the aqueous dispersion of silica-alumina fine particles,
(b) a step of subjecting the silica-alumina fine particle water dispersion to solvent substitution with alcohol,
(c) adding to the silica-alumina fine particle alcohol dispersion an organosilicon compound represented by the following formula (1) in an amount of 1 to 50% by weight of silica-alumina fine particles as R _n -SiO _(4-n) The process,
R _n -SiX _4-n (1)
(Wherein X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen or hydrogen, and n is an integer of 1 to 3), wherein R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms,
(d) a step of adsorbing the organosilicon compound on silica-alumina fine particles while stirring the silica-alumina fine particle alcohol dispersion,
(e) hydrolyzing the organosilicon compound by adding water and a catalyst for hydrolysis;
(f) a step of aging at 40 to 120 DEG C for 0.5 to 24 hours,
The silica-alumina fine particles contained in the silica-alumina fine particle water dispersion obtained in the step (a) have a negative charge per unit surface area of 0.1 to 1.5 占 q ec / m2 at a pH of 2.0 to 7.0, Gt; The method according to claim 1,
Wherein the treatment with the ion exchange resin in the step (a)
(a1) treatment with a cation exchange resin such that the pH is in the range of 1.0 to 6.0,
(a2) The process for producing silica-alumina sol, wherein the pH of the dispersion is higher than the pH of the dispersion in (a1) and is in the range of 2.0 to 7.0. The method according to claim 1,
Wherein at least one step selected from the group consisting of the following steps (g) and (h) is further carried out subsequent to the step (f).
(g) Substitution with an organic solvent
(h) Concentration process The method according to claim 1,
The negative charge (Q ₁ ) per unit surface area of the silica-alumina fine particles of the silica-alumina sol obtained in the step (f) and the negative charge amount per unit surface area (Q ₂ ) of the silica- Wherein the ratio (Q ₁ ) / (Q ₂ ) is in the range of 0.2 to 0.8. The method according to claim 1,
Wherein the molar ratio (M _H2O ) / (M _OC ) of the molar number of water (M _H2O ) of the step (e) to the molar number (M _OC ) of the organic silicon compound is in the range of 1 to 300, ≪ / RTI > The method according to claim 1,
Wherein the molar ratio (M _NH3 ) / (M _OC ) of ammonia and the number of moles of ammonia (M _{NH 3} ) and the number of moles of organosilicon compound (M _OC ) in the step (e) In the presence of a catalyst. The method according to claim 1,
When the negative charge amount per unit surface area of the silica-alumina fine particles of the silica-alumina fine particle water dispersion obtained in the step (f) is 0.5 to 2.0 Micro-coulombs when measured with a dispersion having a solid concentration of 0.5% by weight and a pH of 7.5 ± 1.5 / Cm < 2 >. The average particle diameter is in the range of 5 to 100 nm, the alumina content in the particles is in the range of 0.01 to 5 wt% as Al ₂ O ₃ , and the hydrolyzate of the organosilicon compound represented by the following formula (1) Wherein the negative charge (Q ₁ ) per unit surface area of the silica-alumina fine particles after the surface treatment is 0.5 (mass%) when measured with a dispersion having a solid concentration of 0.5% by weight and a pH of 7.5 ± 1.5, To 2.0 microcoulombs / cm < 2 >.
R _n -SiX _4-n (1)
X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen or a hydrogen atom, and n is an integer of 1 to 3), wherein R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms, A process for producing a silica-alumina sol comprising the steps of: preparing a silica-alumina sol produced by the method of any one of claims 1 to 7, a matrix forming component and a dispersion medium, wherein the total solid concentration is in the range of 30 to 70% Wherein the concentration of the forming component is in the range of 6 to 63 wt% as solid content and the concentration of the silica-alumina fine particles is in the range of 3 to 56 wt% as solid content. And a dispersion medium, wherein the total solid content concentration is in the range of 30 to 70 wt%, the concentration of the matrix forming component is in the range of 6 to 63 wt% %, And the concentration of the silica-alumina fine particles is in the range of 3 to 56% by weight as a solid content. A process for producing a silica-alumina sol according to any one of claims 1 to 7,
And a step of adding a matrix-forming component and a dispersion medium to the silica-alumina sol such that the total solid content is in the range of 30 to 70 wt%, the method comprising:
Wherein the concentration of the matrix forming component is in the range of 6 to 63 wt% as solid content and the concentration of silica-alumina fine particles is in the range of 3 to 56 wt% as solid content. delete delete delete delete delete delete delete delete