KR102019698B1

KR102019698B1 - Reformed zirconia fine particle, dispersion sol of reformed zirconia fine particle and its preparation method

Info

Publication number: KR102019698B1
Application number: KR1020120148395A
Authority: KR
Inventors: 준 야마구치; 마사유키 마츠다; 료 무라구치
Original assignee: 니끼 쇼꾸바이 카세이 가부시키가이샤
Priority date: 2012-12-18
Filing date: 2012-12-18
Publication date: 2019-09-09
Also published as: KR20140078995A

Abstract

Provided is a modified zirconia fine particle powder having excellent dispersibility and fluidity. In the modified zirconia particulate powder surface-treated with an organosilicon compound, the average secondary particle size (D _M2 ) ranges from 5 to 500 nm, the average primary particle size (D _M1 ) ranges from 5 to 500 nm, and the average secondary particle size ( a D _M2) with the average particle size (D _M1) ratio (D _M2) / (D _M1) and the modified zirconia fine particle powder, characterized in that 1 to 10 range, the organic silicon compound to the formula (1) and As the organosilicon compound represented, the content of the organosilicon compound in the fine particles ranges from 1 to 50% by weight as R _n -SiO _{(4-n) / 2} , and the half width of the main peak of the ²⁹ Si MAS NMR spectrum is 3 to 15. ppm range. R _n -SiX _(4-n) (1) wherein R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms and is the same or different from each other, X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, a halogen or It is hydrogen and n is an integer of 1-3.

Description

Modified zirconia fine particle, modified zirconia fine particle, dispersion sol of reformed zirconia fine particle and its preparation method

The present invention relates to a modified zirconia fine particle powder having excellent dispersibility and fluidity, a dispersion using the modified zirconia fine particle powder, and a manufacturing method thereof.

Conventionally, colloidal particles such as silica, alumina, titania, zirconia, zinc oxide, antimony pentoxide, cerium oxide, tin oxide, silica alumina, silica zirconia, and the like are known and used as an optical material in combination with a film for adjusting the refractive index. . For example, silica is a low refractive index material, alumina is a medium refractive index material, and titania, zirconia, etc. are used as a high refractive index material.

Titania particles have a high refractive index and deteriorate dispersion stability, and since titania itself has a photocatalytic activity, there are problems such as light resistance and weather resistance. Thereby, the dispersion stability, light resistance, weather resistance, etc. are improved by compounding other components other than titania, for example, a silica component (patent document 1: Unexamined-Japanese-Patent No. 8-48940). However, depending on the complexing component, it is difficult to completely suppress the photocatalytic activity even if an additive capable of reducing the refractive index is added, thereby resulting in insufficient light resistance, weather resistance, and the like (Patent Document 1).

Therefore, it has been attempted to use zirconia instead of titania, but it is difficult to obtain zirconia sol having a colloidal region having excellent dispersibility and stability even though zirconia particles have substantially no photocatalytic activity but excellent light resistance and weather resistance.

The present applicant has disclosed a method for producing a zirconia sol having excellent dispersibility by hydrothermally treating a hydrolyzate of a zirconium salt in the presence of a particle growth inhibitor such as carboxylic acid (Patent Document 2: Japanese Patent Laid-Open No. 2006-143535). In addition, a method for producing zirconia sol having excellent stability by heating and hydrolyzing zirconium carbonate ammonium in the presence of carbonic acid or the like is disclosed (Patent Document 3: Japanese Patent Laid-Open No. 3-174325). However, even when dried, the zirconia fine particles obtained by the above-mentioned method became strong in aggregation and could not obtain a thing with desired dispersibility.

On the other hand, zirconia fine particles, which are fired at high temperature and pulverized zirconia, have high refractive index and have a large particle size, resulting in uneven particle size distribution, resulting in agglomerated particles and thus dispersibility. It was undesirable to do. On the other hand, in this method, it is known that the addition of alkali and the like (grinding aid) at the time of grinding lowers the particle size and makes the particle size distribution uniform.

Conventionally, surface treatment with an organosilicon compound (silane coupling agent) is performed to improve the dispersibility and stability of various metal oxidizer sol. However, the zirconia fine particles obtained by the calcination and pulverization may be stably dispersed in an alkali region in the presence of alkali coexistence. If the alkaline component is removed by washing and purification, there is a problem that the surface potential is lowered and the dispersibility is significantly lowered.

Particularly, since zirconia fine particles surface-treated in the presence of alkali as a catalyst for hydrolysis of organosilicon compounds have alkali ions, the dispersibility and stability of the surface-treated zirconia fine particles obtained by uneven treatment of organosilicon compounds on the surface are sufficient as necessary. It was not.

On the other hand, when alkali does not coexist, that is, when a hydrolysis catalyst is not used, the hydrolysis rate may be delayed in the trifunctional or less organosilicon compound, and the unreacted organosilicon compound may remain, resulting in insufficient surface treatment.

In addition, when an acid is used as the hydrolysis catalyst, there is a tendency to form a chain hydrolyzate on the particle surface, resulting in the aggregation of the obtained particles and poor dispersibility. In addition, the present applicant has a good dispersibility and stability when the zirconia particles are calcined and then pulverized in the presence of alkali and treated with NH ₄ type ion exchange resin and subjected to efficient surface treatment by surface treatment with an organosilicon compound. It has been disclosed that the organic solvent dispersion liquid of zirconia microparticles | fine-particles can be obtained (patent document 4: Unexamined-Japanese-Patent No. 2009-132819).

Patent Document 1: Japanese Patent Application Laid-Open No. 8-48940 Patent Document 2: Japanese Patent Application Laid-Open No. 2006-143535 Patent Document 3: Publication No. 3-174325 Patent Document 4: Japanese Patent Application Laid-Open No. 2009-132819

Therefore, in consideration of the affinity between the zirconia fine particles and the hydrophobic resin, it is preferable to treat with an organosilicon compound having a trifunctional or lower functionality. However, even when treated with an organosilicon compound having a trifunctional or less than conventional functionality, the surface treatment was insufficient, and the dispersibility with the hydrophobic resin was not sufficient.

Surface treatment with organosilicon compounds with trifunctional or less trifunctional is usually carried out in the presence of alkali such as ammonia as a hydrolysis catalyst. However, in the case of dried powder, it is strongly coagulated and the fluidity of the added powder becomes low. There was a case where it was not possible to disperse easily. Accordingly, it was required to obtain a dispersion in which the organic silicon compound was mixed with an organic resin that was solvent-substituted in an organic solvent after drying with an organic silicon compound. However, in some cases, the dispersion was not uniform, resulting in insufficient stability.

The present inventors have determined that it is difficult to obtain modified zirconia fine particles having excellent dispersibility with hydrophobic resins and the like by examining such problems and grasping the surface treatment state of trifunctional or less organosilicon compounds.

When the tetrafunctional organosilicon compound is hydrolyzed without a hydrolysis catalyst, dispersibility may be improved by the alkyl group in the remaining alkoxide which is unhydrolyzed, but the obtained zirconia powder is strongly aggregated and fluidity and dispersibility are not obtained. There was.

The present inventors have studied the above problems and intensively examined whether it is possible to obtain zirconia fine particle powder having excellent dispersibility when an organosilicon compound having a trifunctional or lower functionality is used for surface treatment. As a result, it was invented by observing the ²⁹ Si MAS NMR spectrum of the surface to grasp the surface treatment state of the trifunctional or less organosilicon compound.

In the case of using an organosilicon compound having a trifunctional or less functional compound using an ammonia catalyst in the presence of a solvent such as methanol, the ²⁹ Si MAS NMR spectrum becomes abnormally sharp. On the other hand, when the peak of the ²⁹ Si MAS NMR spectrum is broadened, when the half width of the main peak is in the range of 3 to 15 ppm, trifunctional or less organosilicon compounds are sufficiently present on the particle surface, and unreacted substances are also minimized, thereby minimizing hydrophobic solvents. The present invention has been completed by discovering that a resin having a high affinity for a resin can be obtained.

Therefore, such surface treatment was found to add a predetermined amount of organosilicon compound to a mixed solvent dispersion liquid such as water / alcohol of zirconia fine particles and to dry (solvent removal) under a fluidized state without adding a catalyst. will be.

[1] modified zirconia particulate powder surface-treated with an organosilicon compound, having an average secondary particle size (D _M2 ) in the range of 5 to 500 nm, an average primary particle size (D _M1 ) in the range of 5 to 500 nm, and an average secondary A modified zirconia particulate powder, wherein the ratio (D _M2 ) / (D _M1 ) between the particle size (D _M2 ) and the average particle size (D _M1 ) ranges from 1 to 10.

[2] The organosilicon compound is an organosilicon compound represented by the following formula (1), wherein the content of the organosilicon compound in the fine particles is R _n -SiO _{(4-n) / 2} (where n is an integer of 1 to 3). The modified zirconia particulate powder of [1], wherein the zirconia fine powder according to [1] is in a range of 1 to 50% by weight and a half width of the main peak of the ²⁹ Si MAS NMR spectrum.

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

(Wherein R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms and may be the same or different from each other. X is an alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, halogen, hydrogen, n is 1 to 3 Is an integer).

[3] The modified zirconia microparticles are prepared by adding an organosilicon compound represented by Formula (1) to water and / or an organic solvent dispersion of the zirconia microparticles and then drying it without adding a hydrolysis catalyst or solvent substitution of the organic silicon compound. [1] or [2] modified zirconia particulate powder, characterized in that it has been made.

[4] The modified zirconia particulate powder of [3], wherein the drying is performed at a temperature of 200 ° C. or lower under reduced pressure or flow.

[5] The modified zirconia fine powder of [1] to [4], wherein the angle of repose is 45 ° C. or less.

[6] The modified zirconia fine particle dispersion according to [1] to [5], wherein the modified zirconia fine particle is dispersed in an organic solvent and / or an organic resin.

[7] The zirconia fine particle dispersion according to [6], wherein the concentration of the modified zirconia fine particle is in the range of 1 to 70% by weight as solid content.

[8] In the powder of modified zirconia fine particles surface-treated with the organosilicon compound consisting of the following steps (d) to (f), the average secondary particle size (D _M2 ) is in the range of 5 to 500 nm and the average primary particle The size (D _M1 ) ranges from 5 to 500 nm and the ratio (D _M2 ) / (D _M1 ) of the average secondary particle size (D _M2 ) to the average primary particle size (D _M1 ) ranges from 1 to 10. A method for producing a modified zirconia fine particle, characterized in that. (d) preparing a water and / or organic solvent dispersion of zirconia fine particles. (e) Process of adding the organosilicon compound represented by following formula (1), without adding the hydrolysis catalyst of an organosilicon compound. (f) Process of drying without solvent replacement

R _n -SiX _4- _n (1)

[9] The organosilicon compound is an organosilicon compound represented by the following formula (1), and the content of the organosilicon compound in the obtained fine particles is R _n -SiO _{(4-n) / 2} (n is an integer of 1 to 3). as a method of producing a modified zirconia fine powder of [9], characterized in that 1 to 50% by weight, and ²⁹ Si MAS NMR half-value width of 3~15 ppm range of the spectrum of the main peak.

R _n -SiX _4- _n (1)

[10] Using the step (d), the average particle size (D _z ) of the zirconia fine particles (before modification) is in the range of 5 to 400 nm, and the ratio of the average secondary particle size (D _M2 ) to (D _M2 ) / ( D _z ) is a method for producing the modified zirconia fine powder according to [8] or [9], wherein 0.2 to 5 (wherein average particle size (D _z ) is adjusted to 10% by weight of solids concentration using water as a dispersion medium). To ultrasonic dispersion and measured by dynamic light scattering method).

[11] The method for producing the modified zirconia fine powder according to [8] or [9], wherein the drying of the step (f) is performed at 200 ° C. or lower under flow or reduced pressure.

[12] The method for producing the modified zirconia fine powder according to [8] to [11], wherein the zirconia fine particles to be used are prepared by the following steps (a) to (c). (a) peptizing or dissolving the zirconium hydroxide gel in the presence of potassium hydroxide and hydrogen peroxide. (b) hydrothermal treatment. (c) washing.

[13] The method for producing the modified zirconia fine powder according to [12], wherein the step (b) is carried out by hydrothermal treatment in the presence of a particle growth regulator.

[14] The method for producing the modified zirconia powder according to [12] or [13], wherein in the step (b), the hydrothermal treatment temperature is in the range of 40 to 300 ° C.

According to the present invention, it is possible to provide a method for producing a modified zirconia fine particle powder having excellent dispersibility and fluidity, a modified zirconia fine particle dispersion having excellent uniform dispersibility, dispersion stability, and modified zirconia fine particle powder. .

The modified zirconia fine particle powder of the present invention is excellent in fluidity and can be easily uniformly dispersed in an organic solvent, an organic resin, or the like as it is in a direct powder. The modified zirconia fine powder is in many cases used as a composite organic solvent and / or organic resin dispersion, but can also be used as a dispersion just before use, and can be stored as a modified zirconia fine powder so it is safe to store and needs to be transported as a dispersion. It is very economical because transportation is safe and transportation cost is reduced.

1 shows a conceptual diagram of the surface state of the modified zirconia fine particle (Example 6) of the present invention.
Fig. 2 shows a conceptual diagram of the surface state of modified zirconia fine particles (comparative example 4) treated by the conventional method.
3 is a chart of ²⁹ Si MAS NMR spectra of modified zirconia fine particles of Example 6. FIG.
4 is a chart of ²⁹ Si MAS NMR spectra of modified zirconia fine particles of Comparative Example 4. FIG.

Hereinafter, the modified zirconia fine particles according to the present invention will be described.

[Modified Zirconia Particulates]

The modified zirconia fine powder according to the present invention is a modified zirconia fine powder surface-treated with an organosilicon compound.

In the present invention, the average secondary particle size (D _M2 ) ranges from 5 to 500 nm and the average primary particle size (D _M1 ) ranges from 5 to 500 nm, and the average secondary particle size (D _M2 ) and average particle size (D _M1) The ratio (D _M2 ) / (D _M1 ) to) is in the range of 1 to 10, preferably in the range of 1 to 7.

In the present invention, the average secondary particle size (D _M2 ) is evaluated by a dynamic light scattering method by ultrasonic dispersion by adjusting the solid content concentration to 30% by weight using methanol as a dispersion medium. On the other hand, the average primary particle size (D _M1 ) measures the particle size in 100 particles of TEM observation. Find the average.

The sum of the degree of aggregation of the modified zirconia fine particles in the range of such a ratio (D _M2 ) / (D _M1 ) is lowered, the dispersibility is increased in the organic solvent and / or the organic resin, and is easily dispersed.

Even when the ratio (D _M2 ) / (D _M1 ) is large, the agglomeration sum of the modified zirconia fine particles is increased, and the separation property may be insufficient in the organic solvent and / or the organic resin. In some cases, stability is insufficient. Even if (D _M2 ) / (D _M1 ) becomes less than 1, it is not usual.

Even when evaluating with methanol dispersion, the dispersibility of the modified zirconia fine particle of the present invention can be well dispersed, and the average particle size and dispersibility can be evaluated with good reproducibility. In addition, there is no big difference even when using another organic solvent. However, when the aqueous dispersion is evaluated after the surface treatment, since the dispersibility is lowered and aggregated, the average particle size cannot be measured, and the primary particle size measured by TEM observation shows a very large deviation.

Organosilicon compounds

As the organosilicon compound, a hydrolyzable organosilicon compound represented by the following formula (1) is used.

R _n -SiX _4- _n (1)

R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms and may be the same or different from each other. As an unsubstituted hydrocarbon group, an alkyl group, a cycloalkyl group, an alkenyl group etc. which have a double bond, etc. are mentioned. Examples of the substituted hydrocarbon group include substituents such as epoxy, glycidoxy, (meth) acryloxy, urethane, amino, amido, imido and ureido, and those in which hydrogen in the hydrocarbon group is halogen-substituted such as fluorine.

X is a C1-C4 alkoxy group, hydroxyl group, halogen, hydrogen, and represents a hydrogen atom. n is an integer of 1-3. When n is two or more, R may mutually be same or different. In addition, some X may mutually be same or different.

In this way, it is possible to obtain modified zirconia fine powder having excellent fluidity and dispersibility by using an organosilicon compound having 1 to 3 functionalities. In addition, as a tetrafunctional organosilicon compound, the modified zirconia fine particle powder may coagulate strongly and hardly obtain fluidity and dispersibility even if a hydrophobic functional group remains.

Specific examples of the organosilicon compounds include methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane and diphenyldiethoxy. Silane, isobutyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (βmethoxyethoxy) silane, 3,3,3-trifluoropropyltrimethoxysilane, methyl-3 , 3,3-trifluoropropyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxyethyltrimethoxysilane, γ-glycidoxyethyltriethoxy Silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ- (β-glycidoxyethoxy) propyltrimethoxysilane, γ- (meth) acrylooxymethyl Trimethoxysilane, γ- (meth) acryloxymethyltriethoxysilane, γ- (meth) acrylooxymeth Trimethoxysilane, γ- (meth) acryloxyethyltriethoxysilane, γ- (meth) acryloxypropyltrimethoxysilane, γ- (meth) acryloxyoxytriethoxysilane, butyltrimethoxy Silane, isobutyltriethoxysilane, hexyltriethoxysilaneoctyltriethoxysilane, decyltriethoxysilane, butyltriethoxysilane, isobutyltriethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, decyl Triethoxysilane, 3-ureidoisopropylpropyltriethoxysilane, perfluorooctylethyltrimethoxysilane, perfluorooctylethyltriethoxysilane, perfluorooctylethyltriisopropylsilane, trifluoro Propyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, trimethoxysilane, methyltrichlorosilane and the like and mixtures thereof.

In addition, γ- (meth) acryloxymethyltrimethoxysilane, γ- (meth) acryloxymethyltriethoxysilane, γ- (meth) acryloxyethoxytrimethoxysilane, and γ- (meth) acryloxyethyltri Acrylic or methacrylic organosilicon compounds such as ethoxysilane, γ- (meth) acryloxypropyltrimethylsilane, and γ- (meth) acryloxypropyltriethoxysilane are modified zirconia particulate powders having excellent fluidity and dispersibility. It can be used suitably for obtaining these.

In this way, the surface treatment is carried out using an organosilicon compound under specific conditions, and the main peak of the ²⁹ Si MAS NMR spectrum is broadened, so that the half width is in the range of 3 to 15 ppm.

The modified zirconia particulate powder according to the present invention has a half width of the main peak of the ²⁹ Si MAS NMR spectrum of 3 to 15 ppm, preferably 3.5 to 12 ppm.

The ²⁹ Si MAS NMR spectrum of the modified zirconia particulate powder surface-treated with the organosilicon compound usually measures two or more different peaks of the chemical shift value derived from Si of the organosilicon compound, but the main peak means the peak with the highest peak height. do. In addition, one peak may be measured depending on conditions.

In the main peak, the peak width becomes sharp when the half width is less than the lower limit. Such modified zirconia fine particles have a surface state close to the modified zirconia fine particles which hydrolyze the organosilicon compound (silane coupling agent) in the presence of a catalyst, and the resulting powder aggregates, resulting in a high repose angle and insufficient fluidity, and an organic solvent and / or Or dispersibility may become inadequate with organic resin.

In the modified zirconia particulate powder of the present invention, the silicon atoms of the organosilicon compound are present in close contact with each other to expand the ²⁹ Si MAS NMR spectrum width on the particle surface, that is, close to the extent to which the nuclear spin of the silicon atoms is affected. It is observed that the surface treated zirconia powder obtained by the surface treatment method has a relatively small interaction between the particle surfaces of the organosilicon compound.

Such a comparison is shown in FIG. 1 and FIG. 2 as a model figure.

1 is a schematic view of the surface of the modified zirconia fine particles of the present invention, the organic silicon compound is bonded to the particle surface as -O-Si-O-Si- in the same manner, and C = O and -COO constituting R on the surface of the zirconia particle It can be seen that-interacts with OH on the surface, resulting in organosilicon compounds lining near the zirconia particle surface. The modified zirconia fine particle powder of the present invention is in a state in which the organosilicon compound is precisely coated on the particle surface, there is no aggregation, the dispersibility is excellent in the organic solvent and / or the organic resin, and the powder is determined to have excellent fluidity due to the small angle of repose. do.

2 is a surface treatment using an ammonium catalyst in the presence of methanol. The OH group and the organosilicon compound on the surface of zirconia fine particles are condensation-polymerized. The organosilicon compounds are condensation-polymerized in the same form to form -Si-O-Si-, and a considerable number of hydrolyzable groups remain in X in the formula (1).

The content of the organosilicon compound in the modified zirconia fine particles also varies depending on the particle size of the zirconia fine particles, the type of the organosilicon compound, etc. and is 1 to 50 as R _n -SiO _{(4-n) / 2} (n is an integer of 1 to 3). % By weight, preferably 2-40% by weight.

The modified zirconia fine particles in which the content of the organosilicon compound is at least strongly aggregated may be obtained, and the fluidity (evaluated by the angle of repose in the present invention) is lowered, so that the dispersibility of the organic solvent, the organic resin, etc. is lowered and uniform monodispersion is achieved. The dispersed dispersion may not be obtained. As a result, even when a transparent film using modified zirconia fine particles is formed, transparency, haze, film strength, scratch resistance, and the like may be insufficient. Even if the content of the organosilicon compound is too high, the effect is not sufficient such that the organosilicon compound effectively bonded to the surface of the zirconia fine particles does not increase and the fluidity, dispersibility with the organic solvent and / or the organic resin are not further improved. Even if there is not much organosilicon compound itself, for example, an unreacted organosilicon compound, an increase of the same reactant as the organosilicon compound, the flowability of the modified zirconia fine powder, the effect of further improving the dispersibility with the organic solvent and / or organic resin. It may not be shown, and may cause a decrease in refractive index depending on the use of the modified zirconia fine particles at the time of addition.

The moisture content in the modified zirconia fine particles is 5% by weight or less, preferably 2% by weight or less as H ₂ O.

Even if the content of water in the modified zirconia fine particles increases as H ₂ O, the fluidity of the modified zirconia fine particle powder is lowered and the dispersibility with the organic solvent and / or the organic resin is insufficient. For example, a dispersion dispersed in an organic solvent may have low transparency and easily settle, resulting in insufficient stability of the dispersion. Moreover, the film formed using the dispersion disperse | distributed to organic resin may have inadequate transparency and film sensitivity. In addition, the content of water in the modified zirconia fine particles is measured by using 0.15 g of modified zirconia powder, manufactured by Kyoto Electronics Co., Ltd .: Karl Fischer Moisture Meter (MKA-610). In addition, moisture content can be adjusted to below an appropriate range by drying.

The average particle size (D _M2 ) of the modified zirconia fines according to the present invention is 5 to 500 nm, preferably in the range of 7 to 400 nm. If the average particle size is in this range, aggregation is minimized, fluidity is increased, and dispersibility with organic solvents and / or organic resins is also increased. As a result, when the transparent film is formed, light scattering is reduced and the haze is also reduced. It is also difficult to obtain when it is below the said range. Even if it exceeds the said range, there exists a restriction | limiting in use, For example, when used for transparent film formation, light scattering becomes strong, transparency becomes inadequate, and haze may increase.

The particle size was measured by the average particle size (D _MZ ) of the modified zirconia fine particles dispersed in methanol to produce a dispersion of 30% by weight of solids concentration irradiated with ultrasonic waves and manufactured by Otsuka Electronics Co., Ltd. : Measured by ELS-Z.

In addition, the average particle size (D _Z ) of the zirconia fine particles (before modification) used in the present invention is 5 to 400 nm, preferably in the range of 7 to 300 nm. In the case of the average particle size (D _Z ) in this range, the above-described average particle size (D _M2 ) of the modified zirconia fine particles is achieved. Even when the average particle size (D _Z ) of the zirconia fine particles is less than the above range, it is difficult to obtain as fine particles in a non-aggregated state, and when the excessively aggregated fine particles are used, the modified zirconia fine particle powder having excellent fluidity and dispersibility of the present invention is obtained. It is difficult to get Even if the average particle size (D _Z ) of the zirconia fine particles exceeds the above range, the average particle size of the obtained modified zirconia fine particles may exceed the predetermined range, and thus, the use thereof is limited.

The average particle size (D _Z ) of the zirconia fine particles is dispersed in water to prepare an aqueous dispersion of 10% by weight of solids concentration irradiated with ultrasonic waves, and the particle size measuring device manufactured by Otsuka Electronics Co., Ltd.: ELS-Z. Measure

The ratio (D _M2 ) / (D _Z ) of the average particle size (D _Z ) of the zirconia fine particles to the average particle size (D _M2 ) of the modified zirconia fine particles is in the range of 0.2 to 5, preferably 0.5 to 3.

Even if the ratio (D _M2 ) / (D _Z ) is increased, the aggregation sum of the modified zirconia fine particles is increased. Dispersibility with an organic solvent and / or an organic resin may be insufficient, and a dispersion may be inferior in transparency and in dispersion stability. When the particle | grains before a modification are aggregated and agglomeration falls by modification, (D _M2 ) / (D _Z ) becomes less than 1. Moreover, even if (D _M2 ) / (D _Z ) falls, this means that raw material particle is aggregated excessively. Since the modification is uneven, dispersibility with an organic solvent, an organic resin, or the like may be insufficient.

In addition, conventionally proposed modified zirconia is agglomerated and dispersibility deteriorates even after powdering, and the angle of repose (fluidity) cannot be evaluated. The angle of repose of the modified zirconia fine particles according to the present invention is also different depending on the particle size of the modified zirconia fine particles. When the average particle size of the modified zirconia fine particles decreases, the angle of repose increases, and when the average particle size increases, the repose angle tends to be low. 45 degrees C or less, Preferably it is 40 degrees C or less. The modified zirconia fine particles of the present invention having such an angle of repose have high fluidity, high miscibility and dispersibility with a viscous acid, and a uniform dispersion. The high repose angle of the modified zirconia fine particle powder may lower the fluidity, the miscibility and dispersibility with point component acids such as resin, and it may be difficult to obtain a uniform dispersion. In addition, even if the modified zirconia fine particles are strongly agglomerated, the angle of repose increases, and when dispersed with the organic solvent and / or the organic resin, the aggregated modified zirconia fine particles may remain and uniform monodispersity may be difficult.

It is preferable that the modified zirconia fine particles which comprise the modified zirconia fine particle which concerns on this invention are crystalline. Specifically, it is preferable that it is monoclinic or cubic. Even if the modified zirconia fine particles are amorphous, fluidity and dispersibility may be insufficient. The reason for this is not clear, but the amorphous zirconia fine particles have a lot of fine pores, and thus, the surface of hydroxyl groups which are not bound to the organosilicon compound due to steric hindrance remains, so that the modified zirconia fine powder can be mixed with the organic solvent and / or the organic resin dispersion medium. Dispersibility may become inadequate. When the modified zirconia fine particles are crystalline, the modified zirconia fine particles are excellent in fluidity, dispersibility, etc., and have a relatively high refractive index and can be used as a high refractive material.

Such modified zirconia fine particles according to the present invention are added to the water and / or organic solvent dispersion of the zirconia fine particles by adding an organosilicon compound represented by the formula (1) without adding a hydrolysis catalyst of the organosilicon compound or performing organic substitution. It can be manufactured by drying to 200 degrees C. or less under reduced pressure or a flow, preferably. Specifically, it is manufactured by the following method.

[Method for Producing Modified Zirconia Particle Powder]

The method for producing the modified zirconia fine particle according to the present invention is characterized by the following steps (d) to (f). (d) preparing a water and / or organic solvent dispersion of zirconia fine particles. (e) Process of adding the organosilicon compound represented by Formula (1). (f) The step of drying without adding a hydrolysis catalyst of the organosilicon compound or without solvent replacement.

Process (d)

A water / or organic solvent dispersion of zirconia fine particles is prepared (zirconia fine particles).

As zirconia microparticles | fine-particles, it is preferable that the average particle size of the obtained modified zirconia microparticles is the said range, and zirconia microparticles | fine-particles which are roughly 5-400 nm, preferably 7-300 nm range are used. Specifically, the average particle size (D _Z ) is 5-400 nm, preferably in the range of 7-300 nm. In the case of the average particle size (D _Z ) in this range, the above-described average particle size (D _M2 ) of the modified zirconia fine particles is achieved.

In this case, it is preferable to use crystalline zirconia fine particles as the zirconia fine particles.

Zirconia Preparation method of fine particles

In the present invention, it is preferable that such zirconia fine particles are obtained by peptizing or dissolving (a) the zirconium hydroxide gel in the presence of potassium hydroxide and hydrogen peroxide, (b) hydrothermal treatment and (c) washing.

The zirconium hydroxide gel also dissolves without peptizing in the presence of potassium hydroxide and hydrogen peroxide. The zirconium hydroxide gel is not particularly limited as long as it is dissolved without peptizing in the presence of potassium hydroxide and hydrogen peroxide, and for example, a zirconium hydroxide gel (zirconia hydrate, zirconium hydroxide) obtained by hydrolyzing or neutralizing a zirconium compound. It is possible to use).

Zirconium compounds include zirconium chloride (ZrCl ₂ ), zirconium oxychloride (ZrOCl ₂ ), zirconium nitrate, zirconyl nitrate, zirconium sulfate, zirconium carbonate, zirconium acetate and the like Umm alkoxide etc. are mentioned.

In addition, when adjusting a zirconium hydroxide gel and a mixed zirconium hydroxide gel, you may use the particle growth regulator mentioned later in order to adjust the size of a gel. The zirconium hydroxide gel and mixed zirconium hydroxide gel can be prepared according to Japanese Patent Application Laid-Open No. 2009-167085 by the applicant of the present invention.

Potassium hydroxide and hydrogen peroxide are added to the zirconium hydroxide gel dispersion. At this time, the concentration of the zirconium hydroxide gel dispersion is adjusted to 0.1 to 20% by weight, preferably 0.2 to 15% by weight, more preferably 0.5 to 10% by weight as solid content. In this concentration range, the production efficiency is increased, and the particle size distribution is also uniform. In addition, when the dispersion concentration is lowered, even if the yield production efficiency is lowered, the particle size distribution of the finally obtained modified zirconia fine particles tends to be nonuniform.

When the number of moles of zirconium hydroxide gel as ZrO ₂ is (M _Zr ), the number of moles of alkali metal hydroxide is (M _OH ) and the number of moles of hydrogen peroxide as H ₂ O ₂ is (M _PO ) / (M _OH ) / (M _Zr ) is 1 to 20, preferably 2 to 15, and (M _PO ) / (M _Zr ) is 5 to 30, preferably 8 to 25.

Even if (M _OH ) / (M _Zr ) is small, the dissolution of the zirconium hydroxide gel becomes insufficient, the average particle size is small, and modified zirconia-based fine particles having a uniform particle distribution cannot be obtained. Even if (M _OH ) / (M _Zr ) is too large, the dissolution of the zirconium hydroxide gel does not increase, and the uniformity of the particle size of the obtained zirconia fine particles is not improved, and the burden of removing and cleaning alkali in the next step becomes large and there is no economic feasibility. .

The temperature at the time of dissolving without peptizing varies with (M _OH ) / (M _Zr ), (M _PO ) / (M _Zr ), but is in the range of 0 to 90 ° C, preferably 5 to 80 ° C. At this temperature, peptising (dissolution) is sufficiently performed, the stability of the dissolving solution is increased, and the economic efficiency is also excellent.

On the other hand, the dissolution time without peptizing is not particularly limited as long as the zirconium hydroxide gel is dissolved without peptizing, and usually 5 hours is sufficient.

In addition, peptising is generally good to eliminate the fine state of the zirconium hydroxide gel, which is agglomerates of fine zirconium hydroxide gel, and to entail some dissolution. Dissolution is to dissolve this.

Moreover, it is good to melt without peptizing and hydrothermal treatment can be performed. It is preferable that modified zirconia-based fine particles having a uniformly high dispersibility and a high refractive index can be obtained by narrowing the distribution of the particle size even when dissolved and hydrothermally treated without peptizing.

The zirconium hydroxide gel solution that was not peptized was then hydrothermally treated. In the dissolving solution without zirconium hydroxide gel peptizing, it is preferable to increase the pH of the solution to which the basic nitrogen compound is added in the range of 9-14, preferably 11-14.

Examples of the basic nitrogen compound include NH ₃ , tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrabutylammonium hydroxide (TBAH), and the like. By adjusting the pH of the dissolving solution to the above range, it is possible to obtain modified zirconia-based fine particles having high crystallinity and high refractive index.

Moreover, it is preferable to perform hydrothermal treatment in presence of a particle growth regulator. Examples of the particle growth regulator include carboxylic acid or carboxylate, hydroxycarboxylic acid salt (having a carboxyl group and alcoholic hydroxyl group in one molecule), hydroxycarboxylic acid group and the like.

Specifically, monocarboxylic acid and monocarboxylic acid, such as tartaric acid, nitrate, acetic acid, fish acid, acrylic acid (unsaturated carboxylic acid), and gluconic acid, malic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid And polyvalent carboxylic acid and polyvalent carboxylate groups such as maleic acid, fumaric acid and phthalic acid. Furthermore, hydroxycarboxylic acid and hydroxy carboxylic acid, such as (alpha)-lactic acid, (beta)-lactic acid, (gamma)-hydroxygil acetic acid, glycerin acid, tartaric acid, citric acid, tropaic acid, benzic acid, are mentioned.

The amount of the grain growth regulator to be added is 0.1 to 20 mol, preferably 1 to 8 mol of the grain growth regulator to 1 mol of ZrO ₂ in the peptizing solution. When the amount of the particle growth regulator used is within this range, the particle distribution of the finally obtained zirconia becomes uniform and the predetermined average particle size can be adjusted.

The hydrothermal treatment temperature is in the range of 40 to 300 ° C, preferably 100 to 250 ° C. If the hydrothermal treatment temperature is within this range, zirconia particles having high crystallinity and uniform particle size distribution can be efficiently obtained.

The hydrothermal treatment time is not particularly limited and varies depending on the hydrothermal treatment temperature, but is usually 0.5 to 12 hours. By hydrothermal treatment in this way, it is possible to produce non-aggregated zirconia fine particles having a uniform particle distribution.

Moreover, when zirconia microparticles are aggregated, it can disperse | distribute as needed. On the other hand, during the dispersion treatment, a dispersion promoter may be added, or a conventionally known apparatus such as a ball mill, a set mill, a roller motion mill, or the like may be used as a method for the dispersion treatment.

As a dispersion promoter, it is possible to use aqueous solution of alkali metal hydroxides, such as NaOH and KOH normally. It is also possible to use basic compounds such as ammonia and organic amines.

The zirconia fine particle dispersion is then washed. As the washing method, if the potassium ions of potassium hydroxide used in the step (a), the particle growth regulator used in the step (b), the dispersion promoter used as necessary, and other cations, anions or salts are not particularly limited, In addition, conventionally known methods may be employed, and examples thereof include an ultrafiltration membrane method, a filtration separation method, a centrifugal filtration method, an ion exchange resin method, and an electrodialysis method.

In addition, the ultrafiltration membrane method and the electrodialysis method can be adopted as a suitable method that does not impair the stability and dispersibility of zirconia fine particles because impurities can be removed without significantly changing the pH of the solution.

The zirconia fine particle dispersibility is preferably washed with a dispersion having a solid content of 10% by weight until the conductivity becomes 3 mS / cm or less, more preferably 0.3 mS / cm or less. When the conductivity of the dispersion is within the above range, the residual amount of impurities such as the ionic component may be 5% by weight or less, preferably 0.5% by weight or less, based on the weight of the zirconia fine particles.

If the impurities such as ionic components are washed and reduced, the reason is not clear, but the adsorption ions on the surface of the zirconia are removed, so that the reactivity with the organosilicon compound is efficient, or the electrical double layer on the surface of the particles is thickened, so that the zirconia particles Since the electrostatic repulsive force in is not large, dispersibility with various organic solvents and the like of the modified zirconia fine particles obtained is improved.

(water)

Whole quantity water can be used as a dispersion medium. When used in combination with the organic solvent, the amount of water used is preferably more than the amount capable of hydrolyzing the hydrolyzable group of the organosilicon compound used.

(Organic solvent)

The organic solvent is not particularly limited as long as it is compatible with water and the organosilicon compound is dissolved. However, methanol, ethanol, propanol, 2-propanol (IPA), butanol, diacetone alcohol, propyl alcohol, tetrahydropropyl alcohol, ethylene glycol, Alcohols such as hexylene glycol and isopropylglycerol: esters such as methyl acetate, ethyl acetate and butyl acetate; Ethers such as diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and propylene glycol monomethyl ether; Ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone, acetyl acetone and acetic acid ester, methyl vertical solver, ethyl vertical solver, butyl vertical solver, toluene, cyclohexylene, isophorone and the like.

Moreover, low boiling point alcohols can be dried and removed at low temperature in the process (f) mentioned later, and can be used suitably. The concentration of the water and / or organic solvent dispersion of the zirconia fine particles is not particularly limited but is preferably in the range of approximately 1 to 30% by weight as a solid content. Moreover, it is preferable to disperse | distribute a dispersion liquid. As a dispersion processing method, methods, such as sufficient stirring and ultrasonic irradiation, are employable.

Process (e)

The organosilicon compound represented by following formula (1) is added.

R _n -SiX _4- _n (1)

As the organosilicon compound, the organosilicon compound described above can be used. In the case of using water as the dispersion medium in the step (d) or when the organic solvent is small, the step (e) may be added as an organic solvent solution of the organosilicon compound. The organosilicon compound has a content of organosilicon compound in the obtained modified zirconia fine particles in the range of 1 to 50% by weight, preferably 2 to 40% by weight, as R _n -SiO _{(4-n) / 2} (n is an integer of 1 to 3). Preference is given to adding a% range.

Although the amount of the organosilicon compound used differs at least depending on the type of the organosilicon compound and the average particle size of the zirconia fine particles, a highly aggregated modified zirconia fine particle dispersion may be obtained, resulting in a decrease in fluidity and dispersibility with organic solvents and organic resins. Even in the case of dispersion, uniformly dispersed dispersions may not be obtained. Even when the amount of the organosilicon compound used is large, for example, the amount of reactant increases, the flowability of the modified zirconia fine powder, and the dispersibility with the organic solvent and / or the organic resin are further improved in the same way as for the unreacted organosilicon compound and the organosilicon compound. In some cases, the effect is not obtained. Therefore, depending on the use of the modified zirconia fine particles, it may be a factor of lowering the refractive index.

Process (f)

It is dried here. The present invention is dried without adding a hydrolysis catalyst of an organosilicon compound or without replacing the organic solvent.

It is preferable to dry to 200 degrees C or less under flow conditions which are not fitting. Even when the catalyst is added and the solvent is replaced, the organosilicon compound is hydrolyzed to perform surface treatment on the OH group on the surface of the particle, so the half peak width of the main peak of the ²⁹ Si MAS NMR spectrum becomes sharper than the range of 3 to 15 ppm. The stability of such a dispersion is lowered and the dispersibility of the dispersion is lowered. Drying is preferably carried out under flow conditions, not under reduced pressure.

Like the present invention, even though the catalyst is not added, the solvent is not changed, and the drying is performed under the flow conditions, not under reduced pressure, the condensation polymerization proceeds in the same manner as the organosilicon compound during the surface treatment to interact with the OH group and the hydrophilic component on the particle surface. This becomes strong.

As a method of drying under flow, a rotary dryer such as a rotary evaporator is used. The use of a tumble dryer does not strongly aggregate the modified zirconia fine particles. Since the modified zirconia fine particle powder which is weakly aggregated in the granule is obtained, the angle of repose becomes small, so that the modified zirconia-based fine particle powder excellent in fluidity and dispersibility can be obtained.

Even when dried under reduced pressure, zirconia fine particles do not strongly aggregate when the solvent is removed at a lower temperature, and modified zirconia fine particles powder easily unidispersed can be obtained even when the zirconia fine particle surface OH group and the organosilicon compound are combined and aggregated. .

The content of water in the modified zirconia fine particles after drying is 5% by weight or less, preferably 2% by weight or less as H ₂ O. Even if the amount of moisture is large, the content of the organosilicon compound tends to be low, and thus, the modified zirconia fine particles have a strong bond in the same form, thereby deteriorating fluidity and dispersibility.

It is preferable that it is lower than normal (atmospheric pressure) under reduced pressure here. In this invention, it is about 800 hPa or less, Preferably it is 500 hPa or less. Also in this case, the pressure does not need to be constant, but it is possible to gradually lower the pressure.

The drying temperature is different depending on the boiling point of the solvent, the drying method and the like, but the drying temperature may be any temperature which is volatilized, and is preferably 200 ° C. or lower. More preferably, it is -30-150 degreeC, More preferably, it is the range of 0-120 degreeC.

Even when the drying temperature is increased, the modified zirconia fine particle powder does not become small in water content, and the modified zirconia fine particles coagulate strongly likewise, so that fluidity and dispersibility may be insufficient.

In addition, the drying temperature does not need to be constant, but may be dried at a low temperature such that, for example, water and / or organic solvent can be substantially removed, and then the temperature may be dried at a temperature in the above range. The modified zirconia fine powder thus obtained has an average secondary particle size (D _M2 ) in the range of 5 to 500 nm, an average primary particle size (D _M1 ) in the range of 5 to 500 nm, and an average secondary particle size (D) as described above. _M2) and to an average particle size (the ratio (D _M2) / _(M1 D) is 1 to 10 and a range of D _M1).

Further, the ratio (D _M2 ) / (D _z ) of the average particle size (D _z ) of the zirconia fine particles to the average particle size (D _M2 ) of the modified zirconia particles is 0.2 to 5.

[Modified Zirconia Particulate Dispersion]

In the modified zirconia fine particle dispersion according to the present invention, the modified zirconia fine particle powder is dispersed in an organic solvent and / or an organic resin.

Organic solvent

As the organic solvent, a conventionally known organic solvent can be used. Specifically, alcohols, such as methanol, ethanol, propanol, 2-propanol (IPA), butanol, diacetone alcohol, propyl alcohol, tetrahydropropyl alcohol, ethylene glycol, hexylene glycol, isopropyl glycerol: methyl acetate, acetic acid Esters such as ethyl ester and butyl acetate; Ethers such as diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and propylene glycol monomethyl ether; Ketones such as acetone, methyl ethyl ketone, methyl isopropyl ketone, acetyl acetone and acetic acid ester, methyl vertical solver, ethyl vertical solver, butyl vertical solver, toluene, cyclohexylene, isophorone and the like.

Organic resin

As the organic resin, a conventionally known organic resin can be used. Specifically, well-known thermosetting resins, thermoplastic resins, electron beam curable resins, etc. can be mentioned as resin for coatings. As such resins, for example, thermoplastic resins such as polyester resins, polycarbonate resins, polyamide resins, polyphenylene oxide resins, thermoplastic acrylic resins, vinyl chloride resins, fluorine resins, vinyl acetate resins and silicone rubbers that have been conventionally used , Thermosetting resins such as urethane resins, melamine resins, silicon resins, ptyrene resins, thermosetting silicone resins, phenolic resins, epoxy resins, unsaturated polyester resins, thermosetting acrylic resins, ultraviolet curing acrylic resins, and ultraviolet curing acrylic resins. have. Furthermore, copolymers and modified substances of two or more kinds of such resins can also be used.

On the other hand, in the case of ultraviolet curing resin, a photoinitiator may be included, and in the case of thermosetting resin, a curing catalyst may be included.

The modified zirconia fine particle dispersion (sol) according to the present invention is prepared by dispersing the above-described modified zirconia fine particle powder in an organic solvent and / or an organic resin.

The method of dispersing is not particularly limited and may be mixed with an organic solvent and / or an organic resin and stirred or mixed without stirring. On the other hand, the type of dispersion medium is different depending on the concentration of the dispersion to be obtained, but if necessary, means for promoting dispersion such as irradiation with ultrasonic waves may be used.

When the modified zirconia fine particles of the present invention are dispersed in the organic solvent, even when the concentration of the modified zirconia fine particles is easily dispersed, it is possible to obtain an organic solvent dispersion sol of the modified zirconia fine particles having excellent transparency and stability. In addition, even when the modified zirconia fine powder of the present invention is dispersed in an organic resin, mechanical energy is not strongly applied, and even when the modified zirconia fine particles are not high, it is possible to easily obtain a uniformly dispersed organic solvent-free zirconia fine particle dispersion. .

When forming a transparent film that does not contain an organic solvent and uses a dispersion of modified zirconia fine particles, it is possible to form a cured transparent film by heating or ultraviolet irradiation instead of removing the solvent by drying.

The modified zirconia fine powder of the present invention can obtain a dispersion in which the modified zirconia fine particles are homogeneously monodispersed without using means such as mechanochemical, which does not strongly aggregate or bond between the modified zirconia fine particles, and has excellent fluidity and dispersibility. have.

The concentration of the modified zirconia fine particles in the organic solvent and / or organic resin dispersion of the obtained modified zirconia fine particles is not particularly limited but can be appropriately selected depending on the intended use. It is usually 1 to 70% by weight, preferably 2 to 60% by weight as solid content.

The organic solvent-free organic resin dispersion of the modified zirconia fine particles does not aggregate or settle the zirconia fine particles even after standing for a long time. A stable sol with transparency.

EXAMPLE

Examples will be described below, but the present invention is not limited to these examples.

(Example 1)

Reforming Zirconia Preparation of fine particle (1) powder

Process (a)

317.9 kg of zirconia hydroxide gel with a solids concentration of 9.5% is suspended in 535.3 kg of water to prepare a zirconia hydroxide gel dispersion with a solids concentration of 3.5% by weight.

354.9 kg KOH aqueous solution having a concentration of 17% by weight, 302.0 kg of aqueous hydrogen peroxide solution having a concentration of 35% by weight, and 88.5 kg of aqueous tartaric acid solution having a concentration of 10% by weight were added to the zirconia hydroxide gel dispersion having a solid content of 3.5% by weight, and stirred at 30 ° C. Stir for 2 hours to peptize the zirconia hydrate gel.

Process (b)

At this time, (M _OH ) / (M _Zr ) was 20, and (M _PO ) / (M _Zr ) was 10. 88.5 kg of a 10% by weight aqueous solution of tartaric acid was added to the solution obtained by peptizing the zirconia hydroxide gel, followed by hydrothermal treatment at 150 ° C for 11 hours in an autoclave.

Process (c)

After the zirconia fine particle dispersion was sufficiently washed with an ultrafiltration membrane, it was dispersed with an ultrasonic homogenizer (US-600TCVP), and a dispersion of zirconia fine particles (1) having a solid content concentration of 11.2% by weight was prepared.

Process (d)

The average particle size of the zirconia fine particles (1) was measured by a particle size measuring device (Otsuka Electronics Co., Ltd .: ELS-Z) and the results are shown in Table 1. At this time, 400 g of the zirconia fine particles (1) dispersion is collected in a beaker. 400 g of methanol is added thereto to prepare a zirconia-based fine particles (1) water / methanol dispersion having a solid concentration of 5.6% by weight.

Process (e)

At this time, the partitioning of methanol in the water / methanol mixed dispersion was 56% by weight. Zirconia fine particles (1) The organosilicon compound in the modified zirconia fine particles obtained in the water / methanol dispersion as γ-methacryloxypropyl trimethoxysilane (Shinwol Chemical Co., Ltd. product: KBM-503) as an organosilicon compound is R ₁ to a -SiO _3/2 so that the addition of 11.2g of 15.3 wt% was stirred for 5 hours.

Process (f)

The modified zirconia fine particles (1) powder was prepared by using a rotary evaporator to gradually reduce the pressure to 50 hPa or less and dry at 60 ° C for 1.5 hours.

In the obtained modified zirconia fine particle (1) powder, water content, crystallinity, average particle size, angle of repose and refractive index were measured, and the results are shown in Table 1. Here, the average particle size is the average particle size measured by the modified zirconia fine particle (1) methanol dispersion mentioned later. In addition, moisture content, angle of repose, and refractive index are measured by the following method.

Moisture content

Kyoto Electronics Co., Ltd. make: The moisture content of the modified zirconia microparticles (1) powder is measured by Karl Fischer moisture meter (MKA-610). The results are shown in Table 1.

Repose

About 30 cc of modified zirconia fine particles (1) powder was filled in a transparent sample bottle made of glass (cylindrical, inner volume of 100 cc), and then rotated about 10 rotations on a horizontal plane at a low speed, and then the angle of the upper surface of the powder was measured with a protractor. The results are shown in Table 1.

Refractive index

In the present invention, the refractive index is measured by the following method using Cargill SeriesA, AA as a standard refractive index and the results are shown in Table 1. (1) Modified zirconia fine particles (1) The dispersion liquid is collected by an evaporator and the dispersion medium is evaporated. (2) This is dried at 80 ° C. for 12 hours to obtain a powder. (3) A standard refractive liquid with known refractive index is added dropwise onto a two or three drop glass plate, and the powder is mixed therewith. (4) The above operation (3) is performed with various refractive index liquids. When the mixed solution becomes transparent, the refractive index of the standard refractive solution is taken as the refractive index of the modified zirconia fine particle (1).

²⁹ Si MAS NMR spectrum

On the other hand, in the modified zirconia fine particles (1) powder, ²⁹ Si MAS NMR spectrum is measured using a nuclear magnetic resonance apparatus (VNMRS-600 manufactured by Agilent technologies). Polydimethylsilane (-34.44ppm) was used as a standard material and measured by a single pulse method under a delay time of 15 seconds and a MAS speed of 6 kHz. The chemical shift value and the full width of the main peak are shown in the table by the computer program attached to the apparatus.

Reforming Zirconia Fine particles (1) Organic solvent Dispersion pharmacy

5 g of modified zirconia fine particles (1) is mixed with methyl isobutyl ketone and thoroughly stirred to prepare modified zirconia fine particles (1) methanol dispersion and modified zirconia fine particles (1) methyl isobutyl ketone dispersion at a solid concentration of 30% by weight. .

In the obtained modified zirconia fine particles (1) methanol dispersion, the average particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (1) methanol dispersion and modified zirconia fine particles (1) methyl isobutyl ketone dispersion having a solid content concentration of 30% by weight, dispersibility and stability were evaluated by the following method, and the results are shown in Table 1.

Dispersibility

The dispersion was filled into a transparent sample bottle made of glass, and the transparency was observed to evaluate the following criteria.

It is a transparent dispersion. : ◎

It is a dispersion with high transparency. : ○

It is a semitransparent dispersion. : △

It is a turbid dispersion: ×

stability

The dispersion was filled in a transparent sample bottle made of glass and allowed to stand at 30 ° C. for 10 days, and the transparency was observed to evaluate the following criteria.

It is a transparent dispersion. : ◎

It is a dispersion with high transparency. : ○

It is a semitransparent dispersion. : △

Turbid or precipitated particles are recognized dispersions: ×

Reforming Zirconia particulate (1) organic resin Dispersion pharmacy

3 g of modified zirconia fine particles (1) powder is mixed with a light acrylate DPE-6A (hereinafter simply DPE-6A) (Diptaerythritol hexaacrylate UV-curable acrylic resin (polyhydric acrylic monomer) manufactured by Kogyo Chemical Co., Ltd.). By stirring, a modified zirconia fine particle (1) organic resin dispersion having a solid content concentration of 30% by weight is prepared. In the obtained modified zirconia fine particle (1) organic resin dispersion, dispersibility was evaluated by the following method, and the results are shown in Table 1.

Dispersibility

It is a transparent dispersion. : ◎

It is a dispersion with high transparency. : ○

It is a semitransparent dispersion. : △

It is a turbid dispersion: ×

(Example 2)

Reforming Zirconia Preparation of fine particle (2) powder

In Example 1, the modified zirconia fine particles (2) powder was prepared in the same manner except that the mixture was dried at 40 ° C for 24 hours. Step (f) The water content, crystallinity, average particle size, angle of repose, and refractive index of the obtained modified zirconia fine particles (2) were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (2) Organic solvent Dispersion pharmacy

A modified zirconia fine particle (2) methanol dispersion and a modified zirconia fine particle (2) MIBK dispersion were prepared in the same manner as in Example 1 except that the modified zirconia fine particle (2) powder was used.

In the obtained modified zirconia fine particles (2) methanol dispersion, the average particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (2) methanol dispersion and modified zirconia fine particles (2) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Fine particles (2) Organic resin Dispersion pharmacy

A modified zirconia fine particles (2) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (2) powder was used. In the obtained modified zirconia fine particles (2) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

(Example 3)

Reforming Zirconia Preparation of fine particle (3) powder

In Example 1, the modified zirconia fine particles (3) powder was prepared in the same manner except that the rotary evaporator was dried at 80 ° C for 1 hour. Step (f) In the obtained modified zirconia fine particles (3) powder, the water content, crystallinity, average particle size, angle of repose and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (3) Organic solvent Dispersion pharmacy

A modified zirconia fine particle (3) methanol dispersion and a modified zirconia fine particle (3) MIBK dispersion were prepared in the same manner as in Example 1 except that the modified zirconia fine particles (3) powder were used.

In the obtained modified zirconia fine particles (3) methanol dispersion, the average particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (3) methanol dispersion and modified zirconia fine particles (3) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Fine particles (3) Organic resin Dispersion pharmacy

A modified zirconia fine particles (3) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (3) powder was used. In the obtained modified zirconia fine particles (3) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

(Example 4)

Reforming Zirconia Preparation of fine particle (4) powder

Example 1 In the step (e) γ- meth acryloyl oxy propyl trimethoxysilane (new moon Chemical Co. Preparation: KBM-503) is an organic silicon compound in the modified zirconia fine particles obtained by R ₁ -SiO _3/2 The modified zirconia fine particles (4) powder was prepared in the same manner except that 9.0 g was added so as to be 12.6% by weight.

In the obtained modified zirconia fine particles (4) powder, water content, crystallinity, average particle size, angle of repose, and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (4) Organic solvent Dispersion pharmacy

A modified zirconia fine particles (4) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (4) powder was used.

In the obtained modified zirconia fine particle (4) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (4) organic resin Dispersion pharmacy

A modified zirconia fine particles (4) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (4) powder was used. In the obtained modified zirconia fine particles (4) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 5)

Reforming Zirconia Preparation of microparticles (5) powder

Example 1 In the step (e) γ- meth acryloyl oxy propyl trimethoxysilane (new moon Chemical Co. Preparation: KBM-503) is an organic silicon compound in the modified zirconia fine particles obtained by R ₁ -SiO _3/2 The modified zirconia fine particles (5) powder was prepared in the same manner except that 22.4 g was added so as to be 36.1% by weight.

In the obtained modified zirconia fine particles (5) powder, the water content, crystallinity, average particle size, angle of repose and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (5) Organic solvent Dispersion pharmacy

A modified zirconia particulate (5) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (5) powder was used.

In the obtained modified zirconia fine particle (5) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (5) Organic resin Dispersion pharmacy

A modified zirconia fine particles (5) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (5) powder was used. In the obtained modified zirconia fine particles (5) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 6)

Reforming Zirconia Preparation of fine particle (6) powder

In the step (d) of Example 1, modified zirconia fine particles (6) powder was prepared in the same manner except that no methanol was added. Step (f) The water content, crystallinity, average particle size, angle of repose and refractive index of the obtained modified zirconia fine particles (6) powders were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table. This spectrum is also shown in FIG.

Reforming Zirconia Fine particles (6) Organic solvent Dispersion pharmacy

A modified zirconia particulate (6) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (6) powder was used.

In the obtained modified zirconia fine particle (6) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (6) Organic resin Dispersion pharmacy

A modified zirconia fine particles (6) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (6) powder was used. In the obtained modified zirconia fine particles (6) organic resin dispersion, the particle size was measured, and the stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 7)

Reforming Zirconia Preparation of fine particle (7) powder

In the step (d) of Example 1, modified zirconia fine particles (7) powder was prepared in the same manner except that isopropyl alcohol (IPA) was added instead of methanol. Step (f) The water content, crystallinity, average particle size, angle of repose, and refractive index of the obtained modified zirconia fine particles (7) were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (7) Organic solvent Dispersion pharmacy

A modified zirconia particulate (7) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (7) powder was used.

In the obtained modified zirconia fine particle (7) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (7) Organic resin Dispersion pharmacy

A modified zirconia fine particles (7) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (7) powder was used. In the obtained modified zirconia fine particles (7) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 8)

Reforming Zirconia Preparation of Fine Particle (8) Powder

In the step (b) of Example 1, modified zirconia fine particles (8) powder was prepared in the same manner except that 531 kg of tartaric acid was added to the solution obtained by peptizing the zirconia hydroxide gel. The moisture content, crystallinity, average particle size, angle of repose, and refractive index of the obtained modified zirconia fine particles (8) powder were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (8) Organic solvent Dispersion pharmacy

A modified zirconia particulate (8) organic solvent dispersion having a solid concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (8) powder was used.

In the obtained modified zirconia fine particle (8) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (8) Organic resin Dispersion pharmacy

A modified zirconia fine particles (8) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (8) powder was used. In the obtained modified zirconia fine particles (8) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 9)

Reforming Zirconia Preparation of fine particle (9) powder

In the step (b) of Example 1, a modified zirconia fine particle (9) powder was prepared in the same manner except that hydrothermal treatment was performed at 110 ° C. for 36 hours. In the obtained modified zirconia fine particles (9) powder, the water content, crystallinity, average particle size, angle of repose and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (9) Organic solvent Dispersion pharmacy

A modified zirconia particulate (9) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (9) powder was used.

In the obtained modified zirconia fine particle (9) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (9) Organic resin Dispersion pharmacy

A modified zirconia fine particles (9) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (9) powder was used. In the obtained modified zirconia fine particles (9) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 10)

Reforming Zirconia Preparation of the fine particle (10) powder

In the step (b) of Example 1, modified zirconia fine particles (10) powder was prepared in the same manner except that the mixture was hydrothermally treated at 180 ° C. for 3 hours. The moisture content, crystallinity, average particle size, angle of repose, and refractive index of the obtained modified zirconia fine particles (10) powders were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (10) Organic solvent Dispersion pharmacy

A modified zirconia particulate (10) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (10) powder was used.

In the obtained modified zirconia fine particles (10) organic solvent dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (10) Organic resin Dispersion pharmacy

A modified zirconia fine particles (10) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (10) powder was used. In the obtained modified zirconia fine particles (10) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 11)

Reforming Zirconia Preparation of the fine particle (11) powder

Γ-acryloxypropyltrimethoxysilane (Shinwol Chemical Co., Ltd. product) instead of (gamma) -methacryloxypropyl trimethoxysilane (Shinwol Chemical Co., Ltd. product: KBM-503) in the process (e) of Example 1. : KBM-5103) was the use by the addition of 11.2g that 15.0% by weight of the organosilicon compound as R ₁ -SiO _3/2 in the obtained modified zirconia particles was prepared, except for the modified zirconia particles 11, a powder in the same manner .

The moisture content, crystallinity, average particle size, angle of repose and refractive index of the obtained modified zirconia fine particles (11) were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Particulates (11) Organic Solvent Dispersion pharmacy

A modified zirconia particulate (11) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (11) powder was used.

In the obtained modified zirconia fine particle (11) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (11) Organic resin Dispersion pharmacy

A modified zirconia fine particles (11) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (11) powder was used. In the obtained modified zirconia fine particles (11) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 12)

Reforming Zirconia Preparation of Fine Particles (12) Powder

Instead of the steps (a), (b) and (c) of Example 1, 218 g of zirconia powder (made by Cheil Heewon Chemical Co., Ltd .: RC-100) was added to an aqueous solution in which 26.8 g of tartaric acid was dissolved in 368 g of pure water, and thereto. A 10 wt% KOH aqueous solution was added to form a zirconia powder dispersion having a pH of 12.3. After dispersing this in a disperser (BATCH SAND manufactured by KANBE CO., LTD.), Using an ultrafiltration membrane, it was washed until the conductivity reached about 300 ㎲ / cm, and 240 g of anion exchange resin (DUOLITE UP5000 manufactured by Rohm and Haas) was added thereto. Was added to wash, and the resin was separated. This was treated as a zirconia fine particle dispersion 12 having a zirconia concentration of 11.2% by weight in the same manner as in Example 1 below to prepare a modified zirconia fine particle 12 powder. Process (f)

The moisture content, crystallinity, average particle size, angle of repose and refractive index of the obtained modified zirconia fine particles (12) were measured and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Particulates (12) Organic Solvent Dispersion pharmacy

A modified zirconia fine particles (12) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (12) powder was used.

In the obtained modified zirconia fine particle (12) organic solvent dispersion, particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

Reforming Zirconia Fine particles (12) Organic resin Dispersion pharmacy

A modified zirconia fine particles (12) organic resin dispersion having a solid concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (12) powder was used. In the obtained modified zirconia fine particles (12) organic resin dispersion, the particle size was measured, and stability and light transmittance (transparency) were evaluated by the following method, and the results are shown in Table 1.

(Example 13)

Reforming Zirconia Preparation of fine particle (13) powder

Modification in which γ-methacryloxypropyltrimethoxysilane (manufactured by Shinwol Chemical Co., Ltd .: KBM-503) was obtained as an organosilicon compound in the zirconia fine particles (1) water / methanol dispersion in the same manner as in step (e) of Example 1. an organosilicon compound in the zirconia particles are then added to 11.2g of 15.3% by weight in which the R ₁ -SiO _3/2 and stirred for 5 minutes.

Here, modified zirconia fine particles (13) powder dried at 60 ° C. for 24 hours in a box dryer were prepared.

The moisture content, crystallinity, average particle size, angle of repose and refractive index of the obtained modified zirconia fine particles (13) powders were measured and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Fine particles (13) Organic solvent Dispersion pharmacy

A modified zirconia particulate (13) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia particulate (13) powder was used.

In the obtained modified zirconia fine particles (13) methanol dispersion, the particle size was measured and the results are shown in Table 1.

On the other hand, dispersibility and stability in the modified zirconia fine particles (13) methanol dispersion and modified zirconia fine particles (13) methyl isobutylcetone dispersion having a solid content concentration of 30% by weight were evaluated and the results are shown in Table 1.

Reforming Zirconia Fine particles (13) Organic resin Dispersion pharmacy

A modified zirconia fine particles (13) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (13) powder was used.

In the obtained modified zirconia fine particles (13) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

(Comparative Example 1)

Reforming Zirconia Particulates ( R1 ) Preparation of Powder

In the same manner as in Example 1, in the step (e), γ-methacryloxypropyltrimethoxysilane (manufactured by Shinwol Chemical Co., Ltd .: KBM-503) was used as the organosilicon compound in the zirconia fine particles (1) water / methanol dispersion. Then, 11.2 g, in which the organosilicon compound in the obtained modified zirconia fine particles becomes 15.3 wt% as R ₁ -SiO _3/2 , is added and stirred for 5 minutes.

The solvent was substituted with methanol using an ultrafiltration membrane and dried at 60 ° C. for 24 hours in a box dryer to prepare modified zirconia fine particles (R1). In addition, it was confirmed that addition of ammonia water to the filtrate during ultrafiltration produced white turbidity and scattered unreacted organosilicon compounds.

In the obtained modified zirconia fine particles (R1) powder, water content, crystallinity, average particle size, angle of repose, and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Particulates ( R1 Organic solvent Dispersion pharmacy

A modified zirconia fine particles (R1) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R1) powder was used.

In the obtained modified zirconia particulate (R1) methanol dispersion, the particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (R1) methanol dispersion and modified zirconia fine particles (R1) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Particulates ( R1 Organic resin Dispersion pharmacy

A modified zirconia fine particles (R1) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R1) powder was used. In the obtained modified zirconia fine particle (R1) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

(Comparative Example 2)

Reforming Zirconia Particulates ( R2 ) Preparation of Powder

In Comparative Example 1, a modified zirconia fine particle (R2) powder was prepared in the same manner except that the resultant was dried at 40 ° C. for 72 hours in a box type drier.

In the obtained modified zirconia fine particles (R2) powder, the water content, crystallinity, average particle size, angle of repose and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Particulates ( R2 Organic solvent Dispersion pharmacy

A modified zirconia fine particles (R2) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R2) powder was used.

In the obtained modified zirconia fine particles (R2) methanol dispersion, the particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (R2) methanol dispersion and modified zirconia fine particles (R2) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Particulates ( R2 Organic resin Dispersion pharmacy

A modified zirconia fine particles (R2) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R2) powder was used. Dispersibility was evaluated in the obtained modified zirconia fine particle (R2) organic resin dispersion, and the result is shown in Table 1.

(Comparative Example 3)

Reforming Zirconia Particulates ( R3 ) Preparation of Powder

In Comparative Example 1, a modified zirconia fine particle (R3) powder was prepared in the same manner except that the resultant was dried at 80 ° C. for 5 hours in a box-type drier.

The moisture content, crystallinity, average particle size, angle of repose and refractive index of the obtained modified zirconia fine particles (R3) powders were measured and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Particulates ( R3 Organic solvent Dispersion pharmacy

A modified zirconia fine particles (R3) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R3) powder was used.

In the obtained modified zirconia fine particles (R3) methanol dispersion, the particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (R3) methanol dispersion and modified zirconia fine particles (R3) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Particulates ( R3 Organic resin Dispersion pharmacy

A modified zirconia fine particles (R3) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R3) powder was used. In the obtained modified zirconia fine particle (R3) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

(Comparative Example 4)

Reforming Zirconia Particulates ( R4 ) Preparation of Powder

In the same manner as in Example 1, the modified zirconia fine particles obtained by using γ-methacryloxypropyl trimethoxysilane (manufactured by Shinwol Chemical Co., Ltd .: KBM-503) as organosilicon compounds in water / methanol dispersions. by the addition of 11.2g that 15.3% by weight of the organosilicon compound as R ₁ -SiO _3/2 and added was 1 min 1.6g of ammonia water having a concentration of 5% by weight after raising the temperature of the dispersion liquid is not stirred herein by 60 ℃ The organosilicon compound is hydrolyzed.

The solvent was substituted with methanol using an ultrafiltration membrane and dried at 60 ° C. for 24 hours in a box-type drier to prepare modified zirconia fine particles (R4) powder. In addition, turbidity was not confirmed when ammonia water was added to the filtrate during ultrafiltration.

In the obtained modified zirconia fine particles (R4) powder, water content, crystallinity, average particle size, angle of repose, and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table. In addition, the spectrum of ¹ H-NMR is shown in FIG.

Reforming Zirconia Particulates ( R4 Organic solvent Dispersion pharmacy

A modified zirconia fine particles (R4) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R4) powder was used.

In the obtained modified zirconia fine particles (R4) methanol dispersion, the particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (R4) methanol dispersion and modified zirconia fine particles (R4) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Particulates ( R4 Organic resin Dispersion pharmacy

A modified zirconia fine particles (R4) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R4) powder was used. In the obtained modified zirconia fine particle (R4) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

(Comparative Example 5)

Reforming Zirconia Particulates ( R5 ) Preparation of Powder

In Comparative Example 4, the modified zirconia fine particles (R5) powder was prepared in the same manner except that the solvent was replaced with methanol using an ultrafiltration membrane and dried at 50 hPa for 1.5 hours at 60 ° C. using a rotary evaporator instead of a box dryer. .

In the obtained modified zirconia fine particles (R5) powder, the water content, crystallinity, average particle size, angle of repose and refractive index were measured, and the results are shown in Table 1. On the other hand, the main peak, the chemical shift value and the half width of the ²⁹ Si MAS NMR spectrum are shown in the table.

Reforming Zirconia Particulates ( R5 Organic solvent Dispersion pharmacy

A modified zirconia fine particle (R5) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particle (R5) powder was used.

In the obtained modified zirconia particulate (R5) methanol dispersion, the particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (R5) methanol dispersion and modified zirconia fine particles (R5) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Particulates ( R5 Organic resin Dispersion pharmacy

A modified zirconia fine particles (R5) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R5) powder was used. Dispersibility was evaluated in the obtained modified zirconia fine particle (R5) organic resin dispersion, and the result is shown in Table 1.

(Comparative Example 6)

Reforming Zirconia Particulates ( R6 ) Preparation of Powder

In Comparative Example 4, after modifying the organosilicon compound, a modified zirconia fine particle (R6) powder was dried at 60 ° C. for 24 hours in a box dryer without solvent replacement.

In the obtained modified zirconia fine particles (R6) powder, water content, crystallinity, average particle size, angle of repose, and refractive index were measured, and the results are shown in Table 1.

Reforming Zirconia Particulates ( R6 Organic solvent Dispersion pharmacy

A modified zirconia fine particles (R6) organic solvent dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R6) powder was used.

In the obtained modified zirconia fine particles (R6) methanol dispersion, the particle size was measured and the results are shown in Table 1. On the other hand, in the modified zirconia fine particles (R5) methanol dispersion and modified zirconia fine particles (R6) methyl isobutyl ketone dispersion having a solid content of 30% by weight, the dispersibility and stability were evaluated and the results are shown in Table 1.

Reforming Zirconia Particulates ( R6 Organic resin Dispersion pharmacy

A modified zirconia fine particles (R6) organic resin dispersion having a solid content concentration of 30% by weight was prepared in the same manner as in Example 1 except that the modified zirconia fine particles (R6) powder was used. In the obtained modified zirconia fine particle (R6) organic resin dispersion, dispersibility was evaluated and the results are shown in Table 1.

Claims

The modified zirconia particulate powder surface-treated with the organosilicon compound represented by the following formula (1) has an average secondary particle size (D _M2 ) of 5 to 500 nm, an average primary particle size (D _M1 ) of 5 to 500 nm, and an average of 2 primary particle size (D _M2) with the average primary particle size ratio of the _{(D M1) (D M2)} / (D M1) is between 1 and 10, the content of the organic silicon compound in the fine R _n -SiO _{(4- n) / 2} as 1 to 50% by weight, the half width of the main peak of the ²⁹ Si MAS NMR spectrum is 3 to 15 ppm, the moisture content is H ₂ O as 5% by weight or less, and the angle of repose is 45 ° C or less. Zirconia Particulate Powder.
R _n -SiX _4-n (1)
Where
R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms, the same as or different from each other,
X is an alkoxy group, hydroxyl group, halogen or hydrogen having 1 to 4 carbon atoms,
n is an integer of 1 or 2.

delete

A modified zirconia fine particle dispersion in which the modified zirconia fine particle powder of claim 1 is dispersed in at least one dispersion medium selected from an organic solvent and an organic resin.

The zirconia fine particle dispersion according to claim 6, wherein the concentration of the modified zirconia fine particles is 1 to 70% by weight as solid content.

The manufacturing method of the modified zirconia fine particle powder surface-treated with the organosilicon compound containing following process (d)-(f).
(d) preparing a dispersion liquid in which zirconia fine particles are dispersed in water or a mixture of water and an organic solvent;
(e) adding an organosilicon compound represented by the following formula (1) to the dispersion without adding a hydrolysis catalyst of an organosilicon compound; And
(f) A step of drying the water content to 5% by weight or less as H ₂ O under a flow of 200 ° C. or lower or at reduced pressure without solvent substitution of the dispersion solution to which the organosilicon compound is added.
R _n -SiX _4-n (1)
Where
R is an unsubstituted or substituted hydrocarbon group having 1 to 10 carbon atoms, the same as or different from each other,
X is an alkoxy group, hydroxyl group, halogen or hydrogen having 1 to 4 carbon atoms,
n is an integer of 1 or 2.

delete

The method according to claim 8, wherein the average particle size (D _z ) of the zirconia fine particles used in the step (d) is 5 to 400 nm, the ratio (D _M2 ) / (D _z ) to the average secondary particle size (D _M2 ) A method for producing modified zirconia fine powder, characterized in that it is 0.2 to 5.
However, the average particle size (D _z ) is measured by the dynamic light scattering method by ultrasonic dispersion by adjusting to 10% by weight of the solid content concentration using water as a dispersion medium.

delete

The method for producing modified zirconia fine powder according to claim 8 or 10, wherein the zirconia fine particles are prepared by the following steps (a) to (c).
(a) peptizing or dissolving the zirconium hydroxide gel in the presence of potassium hydroxide and hydrogen peroxide; (b) hydrothermal treatment; And (c) washing.

13. The process for producing modified zirconia fine powder according to claim 12, wherein in the step (b), hydrothermal treatment is performed in the presence of a particle growth regulator.

The process for producing modified zirconia powder according to claim 12, wherein the hydrothermal treatment temperature in the step (b) is 40 to 300 ° C.