JP2008201634A - Zirconia particle dispersion, organic and inorganic composite material produced from the dispersion and optical member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a dispersion liquid of organic and inorganic particles, which can suppress aggromeration of inorganic fine particles when mixed with a resin and from which an organic and inorganic composite material and an optical member with an excellent transparency and high refractive index can be produced. <P>SOLUTION: The zirconia particle dispersion comprises zirconia fine particles having the number average particle size of 1-15 nm, a dispersion agent, and an organic solvent as a dispersion medium; wherein the components other than the solvent medium have the refractive index of at least 1.80 and the light transmissivity of at least 80% at the wavelength of 589 nm measured on the basis of the thickness of 10 mm. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a zirconia fine particle dispersion and an organic-inorganic composite material using the dispersion. More specifically, an optical component including a material composition excellent in high refraction, transparency, lightness, and workability (for example, spectacle lens, optical device lens, optoelectronic lens, laser lens, pickup) Lens, lens for vehicle camera, lens for portable camera, lens for digital camera, lens for OHP, etc.).

  In recent years, research on optical materials has been actively conducted, and particularly in the field of lens materials, high refractive index, low dispersibility (that is, high Abbe number), heat resistance, transparency, easy moldability, light weight, chemical resistance Development of materials with excellent properties and solvent resistance is strongly desired.

  Plastic lenses are lighter and harder to break than inorganic materials such as glass and can be processed into various shapes, so in recent years they are rapidly spreading not only to spectacle lenses but also to optical materials such as portable camera lenses and pickup lenses. .

  Along with this, it has been required to increase the refractive index of the material itself in order to reduce the thickness of the lens. For example, a technique for introducing a sulfur atom into a polymer (see Patent Document 1 and Patent Document 2) In addition, a technique for introducing a halogen atom or an aromatic ring into a polymer (see Patent Document 3) has been actively studied. However, a plastic material that has a sufficiently large refractive index and has good transparency and can be used as a substitute for glass has not yet been developed.

Since it is difficult to raise the refractive index only with an organic substance, a method for producing a high refractive index material by dispersing an inorganic substance having a high refractive index in a resin matrix has been reported (see Patent Document 4). In order to reduce attenuation of transmitted light due to Rayleigh scattering, it is preferable to uniformly disperse inorganic fine particles having a particle size of 15 nm or less in the resin matrix. However, since primary particles having a particle size of 15 nm or less are very likely to aggregate, it is extremely difficult to uniformly disperse them in the resin matrix. Thus, a technique for introducing a dispersant having a coordinating group capable of interacting with the particle surface in order to suppress aggregation of primary particles (see Patent Document 5) has been reported. However, the refractive index of the dispersant used in this technique is low. For this reason, when an organic-inorganic composite material is used, there is a problem that the inherent high refractive index of the inorganic particles is impaired due to the low refractive index of the dispersant.
JP 2002-131502 A Japanese Patent Laid-Open No. 10-298287 JP 2004-244444 A JP 2003-73564 A JP 2005-185924 A

  Therefore, a plastic material having both high refraction, transparency, and light weight, and an optical component such as a lens including the same, a method and a dispersion for producing the same have not yet been found, Its development was desired.

  The present invention has been made in view of the above circumstances, and an object thereof is to suppress the aggregation of inorganic fine particles when mixed with a resin, and to provide an organic-inorganic composite having excellent transparency and a high refractive index. An object of the present invention is to provide an inorganic fine particle dispersion capable of producing materials and optical components. In particular, an object is to provide an inorganic fine particle dispersion in which inorganic fine particles are uniformly dispersed in an organic solvent by a dispersant having a high refractive index.

  As a result of intensive studies to achieve the above object, the inventors of the present invention impair the original high refractive index of inorganic particles by using a dispersant having a high refractive index and a specific coordinating group. The present inventors have found that a zirconia fine particle dispersion uniformly dispersed in an organic solvent can be obtained. Furthermore, the organic-inorganic composite material obtained by using the dispersion liquid has high refractive index and excellent transparency due to the high refractive index of the dispersant and the uniform dispersion effect of the fine particles, and the completion of the present invention. It came.

That is, the present invention is specified in the matters described in [1] to [13] below.
[1] A zirconia fine particle having a number average particle size of 1 to 15 nm, a dispersant, and an organic solvent as a dispersion medium, the refractive index of the composition other than the dispersion medium is 1.80 or more, and the thickness at a wavelength of 589 nm A zirconia fine particle dispersion having a light transmittance in terms of 10 mm of 80% or more.
[2] A zirconia fine particle dispersion containing a zirconia fine particle having a number average particle size of 1 to 15 nm, a dispersant, and an organic solvent as a dispersion medium, and having a light transmittance of 80% or more in terms of a thickness of 10 mm at a wavelength of 589 nm. And the dispersant is

Ｒ¹⁰ＳＯ₃Ｈ、および、Ｓｉ（ＯＲ¹¹）_mＲ¹² _4-m［上式において、Ｒ¹〜Ｒ¹²はそれぞれ独立に水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、置換または無置換のアリール基を表す。ただし、Ｒ¹〜Ｒ³の少なくとも１つ、Ｒ⁴〜Ｒ⁶の少なくとも１つ、Ｒ⁷〜Ｒ⁹の少なくとも１つ、Ｒ¹⁰、Ｒ¹¹かＲ¹²の少なくとも一方は芳香族基を有する。ｍは１〜４の整数を表す。］からなる群より選択される少なくとも一種の化合物を含有するジルコニア微粒子分散液。
［３］ 前記分散剤が、

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m [wherein, R ^{1 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl. Represents a group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and at least one of R ¹⁰ , R ^11, or R ¹² has an aromatic group. m represents an integer of 1 to 4. A zirconia fine particle dispersion containing at least one compound selected from the group consisting of:
[3] The dispersant is

Ｒ¹⁰ＳＯ₃Ｈ、および、Ｓｉ（ＯＲ¹¹）_mＲ¹² _4-m［上式において、Ｒ¹〜Ｒ¹²はそれぞれ独立に水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、置換または無置換のアリール基を表す。ただし、Ｒ¹〜Ｒ³の少なくとも１つ、Ｒ⁴〜Ｒ⁶の少なくとも１つ、Ｒ⁷〜Ｒ⁹の少なくとも１つ、Ｒ¹⁰、Ｒ¹¹かＲ¹²の少なくとも一方は芳香族基を有する。ｍは１〜４の整数を表す。］からなる群より選択される少なくとも一種の化合物を含有することを特徴とする［１］に記載のジルコニア微粒子分散液。
［４］ 前記分散剤が、

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m [wherein, R ^{1 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl. Represents a group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and at least one of R ¹⁰ , R ^11, or R ¹² has an aromatic group. m represents an integer of 1 to 4. The zirconia fine particle dispersion liquid according to [1], comprising at least one compound selected from the group consisting of:
[4] The dispersant is

およびＲ¹⁰ＳＯ₃Ｈ［上式において、Ｒ¹〜Ｒ¹⁰はそれぞれ独立に水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、置換または無置換のアリール基を表す。ただし、Ｒ¹〜Ｒ³の少なくとも１つ、Ｒ⁴〜Ｒ⁶の少なくとも１つ、Ｒ⁷〜Ｒ⁹の少なくとも１つ、Ｒ¹⁰は芳香族基を有する。］からなる群より選択される少なくとも一種の化合物を含有することを特徴とする［１］または［２］に記載のジルコニア微粒子分散液。
［５］ 前記分散剤が、

And R ¹⁰ SO ₃ H [wherein R ^{1 to} R ¹⁰ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, substituted or unsubstituted Represents a substituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and R ¹⁰ have an aromatic group. The zirconia fine particle dispersion according to [1] or [2], which contains at least one compound selected from the group consisting of:
[5] The dispersant is

［上式において、Ｒ¹〜Ｒ⁹はそれぞれ独立に水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、置換または無置換のアリール基を表す。ただし、Ｒ¹〜Ｒ³の少なくとも２つ、Ｒ⁴〜Ｒ⁶の少なくとも２つ、Ｒ⁷〜Ｒ⁹の少なくとも２つは芳香族基を有する。］からなる群より選択される少なくとも一種の化合物を含有することを特徴とする［１］または［２］に記載のジルコニア微粒子分散液。

[Wherein R ^{1 to} R ⁹ each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. . However, at least two of R ^{1 to} R ³ , at least two of R ^{4 to} R ⁶ , and at least two of R ^{7 to} R ⁹ have an aromatic group. The zirconia fine particle dispersion according to [1] or [2], which contains at least one compound selected from the group consisting of:

[6] A method for producing an organic-inorganic composite material, comprising a step of mixing the zirconia fine particle dispersion liquid according to any one of [1] to [5] with a resin.
[7] The method for producing an organic-inorganic composite material according to [6], further including a step of removing the solvent after the zirconia fine particle dispersion is dropped into and mixed with the resin.

[8] An organic-inorganic composite material produced by the production method of [6] or [7].
[9] An organic-inorganic composite material in which zirconia fine particles having a number average particle size of 1 to 15 nm are dispersed in a resin containing a dispersant,

Ｒ¹⁰ＳＯ₃Ｈ、および、Ｓｉ（ＯＲ¹¹）_mＲ¹² _4-m［上式において、Ｒ¹〜Ｒ¹²はそれぞれ独立に水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、置換または無置換のアリール基を表す。ただし、Ｒ¹〜Ｒ³の少なくとも１つ、Ｒ⁴〜Ｒ⁶の少なくとも１つ、Ｒ⁷〜Ｒ⁹の少なくとも１つ、Ｒ¹⁰、Ｒ¹¹かＲ¹²の少なくとも一方は芳香族基を有する。ｍは１〜４の整数を表す。］からなる群より選択される少なくとも一種の化合物を含有することを特徴とする有機無機複合材料。

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m [wherein, R ^{1 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl. Represents a group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and at least one of R ¹⁰ , R ^11, or R ¹² has an aromatic group. m represents an integer of 1 to 4. An organic-inorganic composite material comprising at least one compound selected from the group consisting of:

[10] An optical component comprising the organic-inorganic composite material according to [8] or [9].
[11] The optical component according to [10], wherein the optical component is a lens substrate.
[12] The optical component according to [11], wherein a refractive index at a wavelength of 589 nm is 1.65 or more.
[13] The optical component according to [11] or [12], wherein the light transmittance in terms of 1 mm thickness at a wavelength of 589 nm is 80% or more.

  The zirconia fine particle dispersion of the present invention can suppress aggregation of fine particles when mixed with a resin, and can provide an organic-inorganic composite material or optical component having excellent transparency and a high refractive index. .

  Hereinafter, the zirconia fine particle dispersion, the organic-inorganic composite material and the method for producing the same, and the optical component including the same will be described in detail. The description of the constituent elements described below may be made based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In the present specification, a numerical range represented by using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.

[Zirconia fine particles]
In the zirconia fine particle dispersion of the present invention, zirconia fine particles having a number average particle size of 1 to 15 nm are used. If the number average particle size of the zirconia fine particles is too small, the characteristics specific to the substance constituting the fine particles may change. On the other hand, if the number average particle size is too large, the influence of Rayleigh scattering becomes significant, and the organic matter produced using the dispersion liquid The transparency of the inorganic composite material may be extremely reduced. Therefore, the number average particle size of the zirconia fine particles in the present invention needs to be 1 to 15 nm, preferably 2 to 13 nm, more preferably 3 nm to less than 10 nm, and further preferably 3 to 9 nm. .

  The method for producing the zirconia fine particles used in the present invention is not particularly limited, and any known method can be adopted. For example, desired zirconia fine particles can be obtained by using a metal halide or an alkoxy metal as a raw material and hydrolyzing in a reaction system containing water.

  Zirconyl sulfate is exemplified as a synthetic raw material for the zirconia fine particles. Metal alkoxides such as zirconium tetraisopropoxide can also be suitably used as a raw material. For example, a known method described in Japanese Journal of Applied Physics, 37, 4603-4608 (1998) or Langmuir, 16 No. 1, 241-246 (2000) can be used. In particular, when synthesizing zirconia fine particles by a sol production method, for example, as in the synthesis of zirconia fine particles using zirconyl sulfate as a raw material, this is passed through a precursor such as hydroxide and then dehydrated or condensed with acid or alkali. A procedure to glue to form a hydrosol can also be employed. In the procedure via such a precursor, it is preferable from the viewpoint of the purity of the final product that the precursor is isolated and purified by any method such as filtration or centrifugation. An appropriate surfactant such as sodium dodecylbenzenesulfonate (abbreviated as DBS) or dialkylsulfosuccinate monosodium salt (manufactured by Sanyo Chemical Industries, Ltd., trade name is Eleminol JS-2) is added to the hydrosol to obtain a sol The particles may be isolated by making them water-insoluble. For example, a known method described in Coloring Materials, Vol. 57, No. 6, 305-308 (1984) can be used.

Further, as a method other than the method of hydrolyzing in water, a method of creating zirconia fine particles in an organic solvent can be employed.
Examples of the solvent used in this method include acetone, methyl ethyl ketone (MEK), dichloromethane, chloroform, toluene, ethyl acetate, cyclohexanone, anisole and the like. These may be used alone or as a mixture of two or more.

  The refractive index of the zirconia fine particles used in the present invention at a wavelength of 589 nm is preferably 1.90 to 3.00, more preferably 1.90 to 2.70, and 2.00 to 2.70. More preferably it is. If zirconia fine particles having a refractive index of 1.90 or more are used, it becomes easy to produce an organic-inorganic composite material or an optical component having a refractive index of greater than 1.80. If zirconia fine particles having a refractive index of 3.00 or less are used, the transmittance is obtained. However, it tends to be easy to produce an organic-inorganic composite material or optical component with 80% or more. In addition, the refractive index in this invention is the value measured at 25 degreeC about the light of wavelength 589nm with the Abbe refractometer (Atago DR-M4).

  The content of the zirconia fine particles in the zirconia fine particle dispersion of the present invention is preferably 0.1 to 80% by mass, more preferably 0.5 to 60% by mass, and 1 to 50% by mass. Is more preferable.

[Dispersant]
The zirconia fine particle dispersion of the present invention contains a dispersant. When a zirconia fine particle is coordinated or modified with an organic compound (dispersant) that is compatible with an organic solvent, the fine particle dispersibility in the organic solvent is improved and the transparency of the zirconia fine particle dispersion of the present invention is improved. To do. Moreover, aggregation of microparticles | fine-particles is suppressed by using a dispersing agent. By combining the effects of these dispersants, the zirconia fine particle dispersion of the present invention exhibits excellent characteristics, and can provide an organic-inorganic composite material or an optical component having high transparency and a high refractive index.

  As a specific example of a preferable structure of the dispersant used in the present invention,

Ｒ¹⁰ＳＯ₃Ｈ、および、Ｓｉ（ＯＲ¹¹）_mＲ¹² _4-mを挙げることができる。好ましくは、

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m can be mentioned. Preferably,

Ｒ¹⁰ＳＯ₃Ｈであり、さらに好ましくは、

R ¹⁰ SO ₃ H, more preferably

であり、特に好ましくは、

And particularly preferably,

である。

It is.

In the above formula, R ^{1 to} R ¹² each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group.

  1-10 are preferable, as for carbon number of an alkyl group, 1-8 are more preferable, and 1-6 are more preferable. 2-10 are preferable, as for carbon number of an alkenyl group, 2-8 are more preferable, and 2-6 are more preferable. 2-10 are preferable, as for carbon number of an alkynyl group, 2-8 are more preferable, and 2-6 are more preferable. 5-20 are preferable, as for carbon number of an aryl group, 5-16 are more preferable, and 5-12 are more preferable. The aryl group herein includes a heteroaryl group. Preferred examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and an isopropyl group. Preferred examples of the alkenyl group include an ethenyl group and a propenyl group. Preferred examples of the alkynyl group As examples, preferred examples of the aryl group include a phenyl group, a naphthyl group, and a biphenyl group.

  The alkyl group, alkenyl group, alkynyl group and aryl group may each be substituted. As the substitution, in addition to these alkyl group, alkenyl group, alkynyl group and aryl group, a halogen atom (for example, fluorine atom, chlorine atom) , Bromine atom, iodine atom) and alkoxy group (for example, methoxy group, ethoxy group).

However, in the above formula, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , at least one of R ¹⁰ , R ¹¹ or R ¹² is aromatic. Has a group. At least two of R ^{1 to} R ³ preferably have an aromatic group, preferably at least two of R ^{4 to} R ⁶ have an aromatic group, and at least two of R ^{7 to} R ⁹ are aromatic. It preferably has a group. The aromatic group may be an aryl group or may be contained in a substituent of an alkyl group, an alkenyl group, or an alkynyl group.

  In the above formula, m represents an integer of 1 to 4. Preferably it is 1-3.

  In the present invention, one type of dispersant may be used alone, or a plurality of types of dispersants may be used in combination.

  In the following, preferred specific examples of the dispersant used in the present invention are listed, but the dispersant that can be used in the present invention is not limited thereto.

  The content of the dispersant in the zirconia fine particle dispersion of the present invention is preferably 0.01 to 40% by mass, more preferably 0.05 to 30% by mass, and 0.05 to 25% by mass. More preferably it is.

[Dispersion medium]
The zirconia fine particle dispersion of the present invention contains an organic solvent as a dispersion medium.
The dispersion medium that can be used in the present invention is not particularly limited as long as it is an organic solvent. For example, alcohols such as methanol, ethanol, isopropanol butanol, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, esters such as ethyl acetate, butyl acetate, γ-butyrolactone, propylene glycol monomethyl ether acetate, ethylene glycol monomethyl Ethers such as ether and anisole, aromatic hydrocarbons such as benzene, toluene and xylene, amides such as dimethylformamide (DMF), N, N-dimethylacetamide (DMAc) and N-methylpyrrolidone (NMP), dichloromethane , Halogenated hydrocarbons such as chloroform and chlorobenzene can be used. Among these, methanol, ethanol, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, toluene, xylene, dichloromethane, and chlorobenzene are preferable, and methyl ethyl ketone, toluene, xylene, and dichloromethane are more preferable. These dispersion media may be used individually by 1 type, and may use multiple types together.

[Zirconia fine particle dispersion]
The zirconia fine particle dispersion of the present invention can be obtained by mixing a dispersant and zirconia fine particles in the above dispersion medium. The mixing method is not particularly limited. For example, an aqueous dispersion of zirconia fine particles is prepared, mixed with a solution in which a dispersant is dissolved in a dispersion medium, and sufficiently stirred, and the organic phase is taken out to obtain the zirconia fine particle dispersion of the present invention. be able to. A method of distilling off water after mixing an organic solvent that is miscible with water in which a dispersant is dissolved in an aqueous dispersion of zirconia fine particles and having a boiling point higher than the boiling point of water and stirring sufficiently The zirconia fine particle dispersion of the present invention can also be obtained.

  The zirconia fine particle dispersion of the present invention preferably has a light transmittance of 10 mm in thickness at a wavelength of 589 nm of 80% or more, more preferably 85% or more. If the light transmittance with a thickness of 10 mm at a wavelength of 589 nm is 80% or more, it is easy to provide an optical component such as an organic-inorganic composite material or a lens having more preferable properties.

  In the zirconia fine particle dispersion of the present invention, the refractive index of the composition other than the dispersion medium is preferably 1.80 or more, more preferably 1.85 or more. If the refractive index of the composition other than the dispersion medium is 1.80 or more, it is easy to provide an optical component such as an organic-inorganic composite material or a lens having more preferable properties.

[Organic inorganic composite materials]
By mixing the zirconia fine particle dispersion of the present invention with a resin, an organic-inorganic composite material can be produced. The method for producing the organic-inorganic composite material of the present invention is not particularly limited. Specifically, a method of independently synthesizing a resin and a zirconia fine particle dispersion and mixing them, a method of synthesizing a resin in the presence of a pre-synthesized zirconia fine particle dispersion, and a zirconia in the presence of a pre-synthesized resin Examples thereof include a method of synthesizing a fine particle dispersion, a method of simultaneously synthesizing both a resin and a zirconia fine particle dispersion, and the organic-inorganic composite material of the present invention may be prepared by any of these methods.

  For example, when adopting a method in which a resin and a zirconia fine particle dispersion are separately synthesized and mixed together, the zirconia fine particle dispersion may be mixed with the resin solution at once, or gradually dropped into the resin solution. Also good. Further, at the time of stirring and mixing, a plasticizer described later may be present. Such a plasticizer may be added in advance to the resin solution or the inorganic fine particle dispersion, or may be added to the resin solution and the zirconia fine particle dispersion. The organic-inorganic composite material of the present invention can be obtained by removing the solvent after mixing.

  In the organic-inorganic composite material of the present invention, the refractive index at a wavelength of 589 nm is preferably 1.65 or more, and more preferably 1.70 or more. If the refractive index at a wavelength of 589 nm is 1.65 or more, it is easy to provide an optical component such as a lens having more preferable properties.

  The organic-inorganic composite material of the present invention preferably has a light transmittance at a wavelength of 589 nm of 80% or more, more preferably 85% or more. If the light transmittance at a wavelength of 589 nm is 80% or more, it is easy to provide an optical component such as a lens having more preferable properties. The light transmittance in the present invention is a value measured with a UV-visible absorption spectrum measuring apparatus UV-3100 (Shimadzu Corporation) after molding a resin to prepare a substrate having a thickness of 1.0 mm.

  The zirconia fine particle content contained in the organic-inorganic composite material of the present invention is preferably 1 to 90% by mass, more preferably 5 to 80% by mass, and further preferably 10 to 70% by mass. . If the zirconia fine particle content is 1% by mass or more, the effect of improving the refractive index is easily obtained, and if it is 90% by mass or less, the mechanical strength of the organic-inorganic composite material tends to be prevented from being lowered.

[resin]
The resin used for the organic-inorganic composite material of the present invention may be any of a thermosetting resin, a photo-curing resin, and a thermoplastic resin, but preferably has a refractive index of more than 1.50 and more than 1.55. More preferably, it is more preferably larger than 1.60, and particularly preferably larger than 1.65. The resin used in the present invention preferably has a light transmittance of 80% or more at a wavelength of 589 nm, more preferably 85% or more.

  The thermosetting resin can be prepared from a thermal polymerization initiator, a polyfunctional (meth) acrylate monomer, or the like.

  The photocurable resin can be prepared from a photopolymerization initiator, a polyfunctional (meth) acrylate monomer, or the like.

  With respect to the thermoplastic resin, the glass transition temperature is preferably 80 ° C to 400 ° C, and more preferably 130 ° C to 380 ° C. If a resin having a glass transition temperature of 80 ° C. or higher is used, an optical component having sufficient heat resistance can be easily obtained, and if a resin having a glass transition temperature of 400 ° C. or lower is used, molding tends to be easily performed.

  The number average molecular weight of the thermoplastic resin used in the present invention is preferably 1,000 to 500,000, more preferably 3,000 to 300,000, still more preferably 5,000 to 200,000, and particularly preferably 10. , 100,000 to 100,000. If the number average molecular weight is 1,000 or more, an organic-inorganic composite material having practical mechanical strength is easily obtained, and if it is 500,000 or less, molding tends to be easily performed. The polymer constituting the resin used in the present invention may be either an addition polymer or a condensation polymer, and the type of polymer is not limited.

  In the present invention, a thermoplastic and thermosetting resin containing sulfur may be used. For example, examples of monomers and polymers having a dithian structure include those described in JP-A-5-148340, JP-A-6-192250, JP-A-11-202101, JP-A-2002-131502, and the like. It is done. Examples of the monomer having an episulfide structure and examples of the cured resin include those described in JP-A Nos. 9-110979, 9-255781, and 10-298287. Examples of the resin having a urethane structure include those described in JP-A-5-208950, JP-A-7-252207, JP-A-2001-342252, and the like. Examples of the resin having a phenylene sulfide structure include those described in JP-A-7-316295, JP-A-8-92367, JP-A-8-104751, and JP-A-8-100065.

  Examples of other resins having a refractive index of 1.65 or more include those described in JP-A Nos. 5-178929 and 7-267919.

  The resin used in the present invention is improved in compatibility with zirconia fine particles.

［Ｒ¹¹〜Ｒ¹⁶はそれぞれ独立に水素原子、ハロゲン原子または置換または無置換のアルキル基を表わす。］、−ＳＯ₃Ｈ、−ＯＳＯ₃Ｈ、−ＣＯ₂Ｈ、−ＯＨ、および―Ｓｉ（ＯＲ¹⁷）_xＲ¹⁸ _3-x［Ｒ¹⁷およびＲ¹⁸はそれぞれ独立に水素原子、置換または無置換のアルキル基、置換または無置換のアルケニル基、置換または無置換のアルキニル基、または置換または無置換のアリール基を表し、ｘは１〜３の整数を表す。］からなる群より選択される官能基を有していてもよい。これらの中で好ましいのは、

[R ^{11 to} R ¹⁶ each independently represents a hydrogen atom, a halogen atom, or a substituted or unsubstituted alkyl group. _{], - SO 3 H, -OSO} 3 H, -CO 2 H, -OH, and _{^{-Si (OR 17) x R 18}} 3-x [R 17 and R ¹⁸ each independently represent a hydrogen atom, a substituted or unsubstituted An alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group, and x represents an integer of 1 to 3. ] May have a functional group selected from the group consisting of Among these, preferred is

−ＳＯ₃Ｈ、−ＯＳＯ₃Ｈ、−ＣＯ₂Ｈから選ばれる官能基を有している態様であり、さらに好ましくは、

It is an embodiment having a functional group selected from —SO ₃ H, —OSO ₃ H, —CO ₂ H, and more preferably,

−ＳＯ₃Ｈ、−ＣＯ₂Ｈから選ばれる官能基を有している態様である。

This is an embodiment having a functional group selected from —SO ₃ H and —CO ₂ H.

  The functional group introduction site may be at the end of the polymer, in the main chain, or in the side chain. Moreover, you may introduce | transduce into several site | parts. These functional groups can be contained in the resin in an amount of, for example, 0.1 to 20% by mass, more preferably 0.2 to 15% by mass, and still more preferably 0.2 to 10% by mass. .

  The method for introducing the functional group into the main chain or side chain of the polymer is not particularly limited. Examples thereof include a method of copolymerizing a monomer having a functional group and a method of introducing a functional group into the main chain or side chain of the polymer by reaction.

  As a method for introducing a functional group into a polymer terminal, a polymer is obtained by polymerization using an initiator having a functional group, a terminator, a chain transfer agent or the like, for example, a phenol terminal part of a polycarbonate obtained from bisphenol A is functionalized. Examples thereof include a method of modifying with a reactive agent containing a group. For example, new polymer experiment 2, synthesis and reaction of polymer (1) synthesis of addition polymer (edited by Society of Polymer Science) 110-112, serial transfer method vinyl system using sulfur-containing chain transfer agent Radical polymerization of monomers, new polymer experiment 2, synthesis / reaction of polymers (1) synthesis of addition-based polymers (edited by the Society of Polymer Science), paragraphs 255-256, and / or Examples include living cationic polymerization using a functional group-containing terminator, ring-opening metathesis polymerization using a sulfur-containing chain transfer agent described in Macromolecules, Vol. 36, Item 7020 to Item 7026 (2003).

  When producing the organic-inorganic composite material of the present invention, only one of the above thermoplastic resins may be used alone, or two or more of them may be mixed and used. When using 2 or more types mixed, it is preferable that the resin mixture after mixing satisfy | fills the conditions of said refractive index.

[Plasticizer]
When the glass transition temperature of the thermoplastic resin constituting the organic-inorganic composite material of the present invention is high, molding may not always be easy. For this reason, in order to lower the molding temperature, the organic-inorganic composite material of the present invention may contain a plasticizer. As a plasticizer used by this invention, what has a structure represented by General formula (2) is preferable.

［一般式（２）中、Ｂ¹およびＢ²はそれぞれ独立に炭素数６〜１８のアルキル基またはアリールアルキル基、ｍは０または１、Ｘは

[In General Formula (2), B ¹ and B ² are each independently an alkyl group or arylalkyl group having 6 to 18 carbon atoms, m is 0 or 1, and X is

のうちのいずれかであり、Ｒ²¹ およびＲ²² はそれぞれ独立に水素原子または炭素数４以下のアルキル基を示す。］

R ²¹ and R ²² each independently represents a hydrogen atom or an alkyl group having 4 or less carbon atoms. ]

In the compound represented by the general formula (2), B ¹ and B ² may be any alkyl group or arylalkyl group within the range of 6 to 18 carbon atoms. If the number of carbon atoms is less than 6, the molecular weight may be too low to boil at the melting temperature of the polymer and generate bubbles. On the other hand, if the number of carbon atoms exceeds 18, the compatibility with the polymer is deteriorated, so that the effect of addition may be insufficient.
Specific examples of the groups B ¹ and B ² include n-hexyl group, n-octyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group, n-octadecyl group and the like. Straight alkyl groups, branched alkyl groups such as 2-hexyldecyl group and methyl-branched octadecyl group, and arylalkyl groups such as benzyl group and 2-phenylethyl group. Specific examples of the compound represented by the general formula (2) include the following, among which W-1 (trade name [KP-L155] manufactured by Kao Corporation) is preferable. However, the plasticizer that can be used in the present invention is not limited to these compounds.

[Molding method]
As a molding method of the organic-inorganic composite material in the present invention, a general thermoplastic resin material molding method such as injection molding, extrusion molding, compression molding, cast molding or the like can be employed. Since the fluidity of the organic-inorganic composite material is low, it is preferably molded by compression molding in the present invention.

[Optical parts]
The organic-inorganic composite material of the present invention is an organic-inorganic composite material having high refractive properties, low dispersibility (high Abbe number), light transmittance, and light weight, and excellent optical properties. Further, the refractive index of the organic-inorganic composite material of the present invention can be arbitrarily adjusted by changing the mixing ratio of zirconia fine particles and resin, for example. The optical component of the present invention includes the above organic-inorganic composite material. The kind of the optical component of the present invention is not particularly limited. In particular, it is suitably used for an optical component utilizing the excellent optical properties of the organic-inorganic composite material, particularly an optical component that transmits light (so-called passive optical component). Functional devices including such optical components include various display devices (liquid crystal display, plasma display, etc.), various projector devices (OHP, liquid crystal projector, etc.), optical fiber communication devices (optical waveguide, optical amplifier, etc.), cameras, videos, etc. The imaging device is exemplified.

  Examples of the passive optical component in such an optical functional device include a lens, a prism, a panel (plate-shaped molded body), a film, an optical waveguide (film-like or fiber-like), an optical disk, and the like. Of these exemplified optical components, the optical component of the present invention can be particularly preferably used as a lens. For such passive optical components, an optional coating layer, for example, a protective layer that prevents mechanical damage to the coated surface due to friction or wear, light with an undesired wavelength that causes deterioration of inorganic particles or substrates, etc. A light absorbing layer that absorbs light, a transmission shielding layer that suppresses or prevents the transmission of reactive low molecules such as moisture and oxygen gas, an antiglare layer, an antireflection layer, a low refractive index layer, etc. A multilayer structure may be used. Specific examples of such an arbitrary coating layer include a transparent conductive film and gas barrier film made of an inorganic oxide coating layer, a gas barrier film made of an organic coating layer, a hard coat, and the like. A known coating method such as a sputtering method, a dip coating method, or a spin coating method can be used.

  The features of the present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

[Analysis and Evaluation Method]
(1) Observation with Transmission Electron Microscope (TEM) It was carried out with an H-9000UHR transmission electron microscope (acceleration voltage 200 kV, degree of vacuum at the time of observation of about 7.6 × 10 ⁻⁹ Pa) manufactured by Hitachi, Ltd. .

(2) Measurement of light transmittance A resin having a thickness of 1.0 mm was prepared by molding a resin to be measured, and light having a wavelength of 589 nm was measured with a UV-visible absorption spectrum measuring apparatus UV-3100 (manufactured by Shimadzu Corporation).

(3) Refractive index measurement Light having a wavelength of 589 nm was measured with an Abbe refractometer (DR-M4 manufactured by Atago Co., Ltd.).

(4) Refractive index of zirconia fine particle dispersion By changing the concentration with the dispersion medium, the refractive index and volume fraction of the composition comprising the dispersant other than the dispersion medium and the zirconia fine particles are estimated from the following Maxwell Garnett equation. It was.

ここで、ｎ_cは分散液の屈折率であり、ｎ_oは分散媒の屈折率であり、ｎ_iは分散媒以外の分散剤とジルコニア微粒子からなる組成物の屈折率であり、ｑは分散剤により修飾された無機微粒子の体積分率である。ｎ_cは実測値、ｎ_oも既知であるため、体積分率ｑおよび分散媒以外の分散剤とジルコニア微粒子からなる組成物の屈折率としてｎ_iを見積もることができる。

Here, n _c is the refractive index of the dispersion, n _o is the refractive index of the dispersion medium, n _i is the refractive index of a composition comprising a dispersant and zirconia fine other than the dispersion medium, q is distributed It is a volume fraction of inorganic fine particles modified with an agent. n _c is the measured value, n for _o also known, it is possible to estimate n _i as the refractive index of a composition consisting of a volume fraction q and dispersant and zirconia fine other than the dispersion medium.

(5) Transmittance of zirconia fine particle dispersion Using a quartz cell having an optical path length of 10 mm, light having a wavelength of 589 nm was measured with a UV-visible absorption spectrum measuring apparatus UV-3100 (manufactured by Shimadzu Corporation).

[Preparation of materials]
(1) Synthesis of zirconia fine particles A zirconium oxychloride solution having a concentration of 50 g / L was neutralized with a 48% aqueous sodium hydroxide solution to obtain a hydrated zirconium suspension. The suspension was filtered and then washed with ion exchanged water to obtain a hydrated zirconium cake. The cake was adjusted to a concentration of 15% by mass in terms of zirconia using ion-exchanged water as a solvent, placed in an autoclave, and hydrothermally treated at 150 ° C. and 150 ° C. for 24 hours to obtain a zirconia fine particle suspension. The generation of zirconia fine particles having a number average particle size of 5 nm was confirmed by TEM.

(2) Preparation of zirconia fine particle MEK dispersion After mixing the zirconia aqueous dispersion synthesized in (1) and the MEK solution in which D-1 made by Tokyo Chemical Industry was dissolved, the mixture was stirred at 50 ° C. for 8 hours. Extraction was performed to prepare a zirconia fine particle MEK dispersion.
Even when other dispersants listed in Table 1 are used, they can be prepared by the same method. Thus, the dispersion liquid was prepared by changing the type and amount of the dispersant as shown in Table 1. In Comparative Example 1, PLAAD ED151 (phosphate ester having no aromatic group) manufactured by Enomoto Kasei Co., Ltd. described in Patent Document 5 was used as a dispersant. In Comparative Example 2, benzoic acid having a high refractive index was used as a dispersant. Table 1 also shows the refractive index and transmittance of each dispersion obtained.

(3) Synthesis of Resin Synthesis of Living Radical Polymerization Initiator A:
A 200 ml three-necked flask equipped with a reflux condenser and a gas introduction cock was charged with 20 g (75.8 mmol) of α, α′-dibromo-p-xylene and 70 ml of m-xylene, and heated under reflux with triisopropyl phosphine in a nitrogen stream. A solution of 16.8 g (80.7 mmol) of phyto in 20 ml of m-xylene was added dropwise. After completion of the dropwise addition, the mixture was heated to reflux for 3 hours, and the solvent was distilled off. Purification by silica gel column chromatography gave initiator A (yield 53%).

Synthesis of P-1:
In a 200 ml three-necked flask equipped with a reflux condenser and a gas introduction cock, copper bromide 0.41 g (2.86 mmol), styrene 59.6 g (0.57 mol), N, N, N ′, N ′, N ″ − After charging 0.5 g (2.86 mmol) of pentamethyldiethylenetriamine and 1.0 g (2.86 mmol) of initiator A, the atmosphere was purged with nitrogen five times and then heated at 80 ° C. for 5 hours under a nitrogen stream. After returning to room temperature, 30 g of alumina and 50 ml of toluene were added, stirred for 10 minutes, and filtered through Celite. The filtrate was poured into a large amount of methanol and precipitated, and the precipitate was collected by filtration, washed with a large amount of methanol, and dried in vacuo at 60 ° C. for 3 hours to obtain a polymer (yield 38%).
A 100 ml three-necked flask equipped with a gas introduction cock was charged with 10 g of the polymer obtained above, 2.3 g (15 mmol) of trimethylsilyl bromide, and 40 ml of methylene chloride, and stirred at room temperature for 24 hours in a nitrogen stream. After adding 10 ml of water and stirring for 1 hour, the solution was poured into a large amount of methanol and precipitated. The precipitate was collected by filtration, washed with a large amount of methanol, and vacuum dried at 60 ° C. for 3 hours to obtain a resin P-1. (Yield 96%. Number average molecular weight 25,200, weight average molecular weight 28,200).

(4) Preparation of organic-inorganic composite material The zirconia fine particle MEK dispersion synthesized in (2) was dropped into the MEK solution of resin P-1 over 5 minutes, and this was stirred for 1 hour, and then the solvent was removed. An organic-inorganic composite material was obtained as a powder.

  As is clear from Table 1, the refractive index of the dispersant-modified zirconia fine particles uniformly dispersed in the organic solvent according to the present invention is greater than 1.80, and the light transmittance in terms of 10 mm thickness at a wavelength of 589 nm is 80. % Zirconia fine particle dispersions were obtained (Examples 1 to 7). In Comparative Example 1, since the refractive index of the dispersant is low, the high refractive index of the inorganic fine particles is impaired, and a composition other than the dispersion medium having a refractive index higher than 1.80 cannot be obtained. Although the agent has a high refractive index, the dispersibility is low, and the fine particle dispersion has a light transmittance higher than 80%. Further, since the light transmittance was low, the refractive index could not be measured with an Abbe refractometer.

[Manufacture of optical components by thermoforming]
Each organic-inorganic composite material synthesized in (4) was heat-molded at 220 ° C. to produce a molded article for a lens having a thickness of 1 mm (Examples 8 to 14 and Comparative Examples 3 and 4). Table 2 shows the kind of the zirconia fine particle dispersion used and the amount used as an inorganic component. In Comparative Example 5, only the resin was molded without adding inorganic fine particles.
The molded body was cut and the cross section was observed with a TEM to confirm whether the inorganic fine particles were uniformly dispersed in the resin. Further, light transmittance measurement and refractive index measurement were performed. These results are listed in Table 2 below. Thereafter, the lens molding was molded into a lens shape to obtain a lens as an optical component.

  As is apparent from Table 2, optical components having a refractive index greater than 1.65 and good transparency were obtained according to the present invention (Examples 8 to 14). In Comparative Example 1, since the refractive index of the composition other than the dispersion medium is low, an optical component having a sufficiently high refractive index cannot be obtained. In Comparative Example 2, the dispersibility is low, the fine particles are aggregated, and light transmission Since the refractive index was low, the refractive index could not be measured with an Abbe refractometer.

  The zirconia dispersion liquid of the present invention is uniformly dispersed in an organic solvent without impairing the high refractive index of the inorganic fine particles, and the optical component of the present invention comprising this has high refractive properties and light transmittance. It also has light weight. In addition, according to the present invention, it is possible to provide an optical component with an arbitrarily adjusted refractive index relatively easily. Therefore, the present invention is useful for providing a wide range of optical components such as a high refractive lens, and has high industrial applicability.

Claims (13)

  A zirconia fine particle having a number average particle size of 1 to 15 nm, a dispersant, and an organic solvent as a dispersion medium, the refractive index of the composition other than the dispersion medium is 1.80 or more, and the thickness is converted to 10 mm at a wavelength of 589 nm. A zirconia fine particle dispersion having a light transmittance of 80% or more. A zirconia fine particle dispersion containing a zirconia fine particle having a number average particle size of 1 to 15 nm, a dispersant, and an organic solvent as a dispersion medium, and having a light transmittance of 80% or more in terms of a thickness of 10 mm at a wavelength of 589 nm, The dispersant is

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m [wherein, R ^{1 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl. Represents a group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and at least one of R ¹⁰ , R ^11, or R ¹² has an aromatic group. m represents an integer of 1 to 4. A zirconia fine particle dispersion containing at least one compound selected from the group consisting of: The dispersant is

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m [wherein, R ^{1 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl. Represents a group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and at least one of R ¹⁰ , R ^11, or R ¹² has an aromatic group. m represents an integer of 1 to 4. The zirconia fine particle dispersion according to claim 1, comprising at least one compound selected from the group consisting of: The dispersant is

And R ¹⁰ SO ₃ H [wherein R ^{1 to} R ¹⁰ are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, substituted or unsubstituted Represents a substituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and R ¹⁰ have an aromatic group. The zirconia fine particle dispersion according to claim 1, comprising at least one compound selected from the group consisting of: The dispersant is

[Wherein R ^{1 to} R ⁹ each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. . However, at least two of R ^{1 to} R ³ , at least two of R ^{4 to} R ⁶ , and at least two of R ^{7 to} R ⁹ have an aromatic group. The zirconia fine particle dispersion according to claim 1, comprising at least one compound selected from the group consisting of:   The manufacturing method of the organic inorganic composite material characterized by including the process of mixing the zirconia fine particle dispersion liquid as described in any one of Claims 1-5 with resin.   The method for producing an organic-inorganic composite material according to claim 6, further comprising a step of removing the solvent after the zirconia fine particle dispersion is dropped and mixed in the resin.   An organic-inorganic composite material produced by the production method according to claim 6 or 7. An organic-inorganic composite material in which zirconia fine particles having a number average particle size of 1 to 15 nm are dispersed in a resin containing a dispersant, wherein the dispersant is

R ¹⁰ SO ₃ H and Si (OR ¹¹ ) _m R ¹² _4-m [wherein, R ^{1 to} R ¹² are each independently a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl. Represents a group, a substituted or unsubstituted alkynyl group, or a substituted or unsubstituted aryl group. However, at least one of R ^{1 to} R ³ , at least one of R ^{4 to} R ⁶ , at least one of R ^{7 to} R ⁹ , and at least one of R ¹⁰ , R ^11, or R ¹² has an aromatic group. m represents an integer of 1 to 4. An organic-inorganic composite material comprising at least one compound selected from the group consisting of:   An optical component comprising the organic-inorganic composite material according to claim 8.   The optical component according to claim 10, wherein the optical component is a lens substrate.   The optical component according to claim 11, wherein a refractive index at a wavelength of 589 nm is 1.65 or more.   The optical component according to claim 11 or 12, wherein a light transmittance in terms of 1 mm thickness at a wavelength of 589 nm is 80% or more.