JP2006176392A - Process for producing modified stannic oxide sol and stannic oxide/zirconium oxide composite sol - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for producing stable modified sol to be used for a component of a hard coat agent to be applied to the surface of plastic lenses or for other applications. <P>SOLUTION: The stable modified sol contains modified metal oxide particles which have particle sizes of 4.5 to 60 nm and which comprise, as nuclei, colloidal particles (A) having a particle size of 4 to 50 nm and comprising stannic oxide particles or composite particles of stannic oxide particles and zirconium oxide particles in a weight ratio of ZrO<SB>2</SB>:SnO<SB>2</SB>being 0:1 to 0.50:1, and, as applied on their surfaces, alkylamine-containing Sb<SB>2</SB>O<SB>5</SB>colloidal particles (B1), or composite colloidal particles (B2) of diantimony pentoxide and silicon dioxide, or tungsten oxide/stannic oxide/silicon dioxide composite colloidal particles (B3), wherein the weight ratio of (B)/(A) is 0.01 to 0.50 on the basis of the weight ratio of their metal oxides. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

In the present invention, the surface of a tin oxide colloid or a stannic oxide-zirconium oxide composite colloidal particle is treated with an alkylamine-containing Sb ₂ O ₅ colloidal particle, an antimony pentoxide / silicon dioxide composite colloidal particle, or a tungsten oxide / oxidized oxide. The present invention relates to a method for producing modified stannic oxide or modified stannic oxide-zirconium oxide colloidal particles having a particle diameter of 4 to 60 nm formed by coating with stannic and silicon dioxide composite colloidal particles. .

  The sol of the present invention is used for various other applications as a component of a hard coat agent applied to the surface of a plastic lens.

  In order to improve the surface of a plastic lens that has been frequently used in recent years, a metal oxide sol having a high refractive index is used as a component of a hard coat agent applied to the surface.

  A hard coating agent containing 1 to 300 nm particles of a metal oxide such as Al, Ti, Zr, Sn, and Sb is described (see, for example, Patent Document 1).

Although a stable sol of tungsten oxide alone is not yet known, WO ₃ : SiO ₂ : M ₂ O (where M represents an alkali metal atom or an ammonium group) obtained by addition of silicate has a molar ratio of 4. Sols that are ˜15: 2 to 5: 1 have been proposed (see, for example, Patent Document 2).

  A silicic acid-stannic acid composite sol with a Si: Sn molar ratio of 2 to 1000: 1 has been proposed (see, for example, Patent Document 3).

The surface is a WO ₃ / SnO ₂ weight ratio of 0.5 to 100 and a particle size of 2 to 7 nm using a colloidal particle of a metal oxide of valence 3, 4, or 5 having a particle size of 4 to 50 nm as a nucleus. It is composed of a modified metal oxide colloid having a particle diameter of 4.5 to 60 nm formed by coating with colloidal particles of tungsten oxide-stannic oxide composite, and contains 2 to 50% by weight of these total metal oxides A stable sol has been proposed (see, for example, Patent Document 4).

The _SnO 2 -ZrO ₂ composite colloidal particles having a particle diameter of a weight ratio and 4~50nm of ZrO ₂ / SnO ₂ as 0.02 to 1.0 as a nucleus, the surface, WO ₃ of 0.5 to 100 A stable sol of modified SnO ₂ —ZrO ₂ composite comprising particles of a structure coated with a colloidal particle of WO ₃ —SnO ₂ composite having a weight ratio of / SnO ₂ and a particle diameter of ₂ to 7 nm has been proposed (For example, see Patent Document 5).

A particle (C) obtained by coating the surface of a metal oxide colloidal particle (A) having a primary particle size of 2 to 60 nm with a coating (B) comprising colloidal particles of an acidic oxide. There is disclosed a stable modified metal oxide sol containing and containing (C) in a proportion of 2 to 50% by weight in terms of metal oxide and having a primary particle size of 2 to 100 nm. The core metal oxides are SnO ₂ particles and SnO ₂ —ZrO ₂ composite colloidal particles, and the coating contains alkylamine-containing Sb ₂ O ₅ particles (M / Sb ₂ O ₅ molar ratio is 0.02 to 4). .00) (see, for example, Patent Document 6).

  After mixing an alkali silicate aqueous solution or silicate sol solution with an alkali antimonate aqueous solution or an alkali stannate aqueous solution so that the molar ratio of Si: Sb or Si: Sn is 2 to 1000: 1, the mixture is A method for producing a silicic acid-antimonic acid complex sol liquid or a silicic acid-stannic acid complex sol liquid, characterized in that it is decationized by an acid ion exchanger (for example, Patent Document 7).

A silicon oxide antimony oxide composite sol is described in which antimony oxide colloidal particles containing 0.1 to 50% by weight of an inorganic silicate compound as SiO ₂ are dispersed in a dispersion medium (for example, Patent Document 8). ).
Japanese Patent Publication No. 63-37142 (Claims) JP 54-52686 A (Claims) Japanese Patent Publication No. 50-40119 (Claims) JP-A-3-217230 (Claims) JP-A-6-24746 (Claims) JP 2001-122621 (Claims) Japanese Patent Publication No. 50-40119 (Claims) Japanese Patent Publication No. 7-25549 (Claims)

When conventional metal oxide sols, especially cationic metal oxide sols, are used as components of the hard coating agent, not only the stability of the obtained hard coating agent is not sufficient, but also the cured film of this hard coating agent is transparent. Property, adhesion, weather resistance and the like are not sufficient. When Sb ₂ O ₅ sol is used as a hard coating agent component, the refractive index of Sb ₂ O ₅ is about 1.65 to 1.70, so the refractive index of the plastic substrate of the lens is 1.6 or more. In this case, the refractive index of the cured film is no longer sufficiently improved with this Sb ₂ O ₅ sol.

  The tungsten oxide sol described in JP-A-54-52686 is obtained by adding silicate to an aqueous solution of tungstic acid obtained by decation treatment of an aqueous solution of tungstate. When used as a component of a hard coating agent, the effect of improving the refractive index of the coating film is small.

  The silicic acid-stannic acid complex sol described in Japanese Patent Publication No. 50-40119 is obtained by subjecting a mixed aqueous solution of alkali silicate and alkali stannate to a decation treatment. When used as a component of a coating agent, the effect of improving the refractive index of the coating film is small.

  The modified metal oxide sol described in JP-A-3-217230 has a refractive index of 1.7 or more, is stable, can be used as a component of a hard coating agent for plastic lenses, and requires a required hard coat. The film performance such as scratch resistance, transparency, adhesion, water resistance, weather resistance and the like can be substantially satisfied. However, when the refractive index of the plastic substrate of the lens is 1.7 or more, the refractive index of the cured film is not sufficiently improved.

  The modified stannic oxide-zirconium oxide sol described in JP-A-6-24746 is stable with a refractive index of 1.7 or more, and can be used as a component of a hard coating agent for plastic lenses. The performance of the hard coat film, such as scratch resistance, transparency and adhesion, can be substantially satisfied. However, this sol does not sufficiently improve the refractive index of the cured coating when the refractive index of the plastic substrate of the lens is 1.7 or more.

  The present invention is a state when the modified metal oxide described in JP-A-3-217230 and JP-A-6-24746 is used as a hard coat film, for example, scratch resistance, transparency, adhesion, water resistance, Stability of modified stannic oxide or modified stannic oxide-zirconium oxide, which is a sol for further improving weather resistance, etc., stable in a wide pH range and having a high refractive index (1.9 or more) Another object of the present invention is to provide a metal oxide sol that can be used as a component for improving the performance of a hard coat film applied to the surface of a plastic lens and mixed with the hard coat paint.

As a first aspect of the present invention, the following step (a1), step (b1), step (c1) and step (d1):
(A1) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight,
(B1) step: a step of hydrothermally treating the stannic oxide aqueous sol obtained in the step (a1) for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.,
Step (c1): A molar ratio of stannic oxide aqueous sol obtained in Step (b1) to M / Sb ₂ O ₅ of 0.02 to 4.00 (where M represents an amine molecule) and 1 A step of mixing an alkylamine-containing Sb ₂ O ₅ aqueous sol having a particle diameter of ˜20 nm with a weight ratio of Sb ₂ O ₅ / SnO ₂ converted to the metal oxide to 0.01 to 0.50, and (D1) Step: A method for producing a stable sol of modified stannic oxide colloidal particles, including the step of aging the aqueous medium obtained in Step (c1) at 20 to 300 ° C. for 0.1 to 50 hours,
As a 2nd viewpoint, the following (a2) process, (b2) process, (c2) process, and (d2) process:
Step (a2): a stannic oxide aqueous sol having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50 wt%, and an oxyzirconium concentration of 0.1 to 50 wt% in terms of ZrO ₂ An aqueous salt solution was mixed in a weight ratio of 0.001 to 0.50 as ZrO ₂ / SnO ₂ , and the resulting mixture was heated at 60 to 100 ° C. for 0.1 to 50 hours to give 4 to 4 Preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 50 nm;
(B2) Step: The stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a2) is subjected to water for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. A step of performing a heat treatment,
Step (c2): Molar ratio of stannic oxide-zirconium oxide composite aqueous sol obtained in step (b2) and M2 / Sb ₂ O ₅ of 0.02 to 4.00 (where M is an amine molecule) And an alkylamine-containing Sb ₂ O ₅ aqueous sol having a particle diameter of 1 to 20 nm in a weight ratio of Sb ₂ O ₅ / (SnO ₂ + ZrO ₂ ) in terms of the metal oxide is 0.01 to Modified stannic oxide-oxidation comprising the steps of mixing to 0.50 and (d2) step: aging the aqueous medium obtained in step (c2) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of zirconium composite colloidal particles,
As a 3rd viewpoint, the following (a3) process, (b3) process, (c3) process, and (d3) process:
(A3) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight;
(B3) step: a step of subjecting the aqueous stannic oxide sol obtained in the above step (a3) to hydrothermal treatment for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.,
Step (c3): stannic oxide aqueous sol obtained in step (b3) above, antimony pentoxide having a SiO ₂ / Sb ₂ O ₅ molar ratio of 0.55 to 55 and a particle size of 5 nm or less; An aqueous sol containing composite colloidal particles of silicon dioxide is mixed to 0.01 to 0.50 in a weight ratio of (Sb ₂ O ₅ + SiO ₂ ) / (SnO ₂ ) converted to the metal oxide. Step (d3): A method for producing a stable sol of modified stannic oxide colloidal particles, comprising aging the aqueous medium obtained in Step (c3) at 20 to 300 ° C. for 0.1 to 50 hours ,
As a 4th viewpoint, the following (a4) process, (b4) process, (c4) process, and (d4) process:
Step (a4): a stannic oxide aqueous sol having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50 wt%, and an oxyzirconium concentration of 0.1 to 50 wt% in terms of ZrO ₂ An aqueous salt solution was mixed in a weight ratio of 0.001 to 0.50 as ZrO ₂ / SnO ₂ , and the resulting mixture was heated at 60 to 100 ° C. for 0.1 to 50 hours to give 4 to 4 Preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 50 nm;
Step (b4): Hydrothermal treatment of the stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a4) at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours. The process of performing,
Step (c4): The stannic oxide-zirconium oxide composite aqueous sol obtained in step (b4) has a SiO ₂ / Sb ₂ O ₅ molar ratio of 0.55 to 55 and a particle size of 5 nm or less. An aqueous sol containing composite colloidal particles of antimony pentoxide and silicon dioxide is converted into its metal oxide in a weight ratio of (Sb ₂ O ₅ + SiO ₂ ) / (SnO ₂ + ZrO ₂ ) of 0.01 to Modified stannic oxide-oxidation comprising the steps of mixing to 0.50 and (d4) step: aging the aqueous medium obtained in step (c4) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of zirconium composite colloidal particles,
As a fifth aspect, the following step (a5), step (b5), step (c5) and step (d5):
(A5) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight;
(B5) step: a step of subjecting the stannic oxide aqueous sol obtained in the step (a5) to a hydrothermal treatment for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.,
Step (c5): The aqueous stannic oxide sol obtained in Step (b5), a WO ₃ / SnO ₂ weight ratio of 0.1 to 100 having a particle diameter of 2 to 7 nm and 0.1 to 100 An aqueous sol containing a composite colloidal particle of tungsten oxide-stannic oxide-silicon dioxide having a SiO ₂ / SnO ₂ weight ratio was converted into its metal oxide (SnO ₂ + WO ₃ + SiO ₂ ) / (SnO ₂ ) mixing at a weight ratio of 0.01 to 0.50, and (d5) step: aging the aqueous medium obtained in step (c5) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of modified stannic oxide colloidal particles,
As a sixth aspect, the following step (a6), step (b6), step (c6) and step (d6):
Step (a6): a stannic oxide aqueous sol having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50% by weight, and an oxyzirconium concentration of 0.1 to 50% by weight in terms of ZrO ₂ An aqueous salt solution was mixed in a weight ratio of 0.001 to 0.50 as ZrO ₂ / SnO ₂ , and the resulting mixture was heated at 60 to 100 ° C. for 0.1 to 50 hours to give 4 to 4 Preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 50 nm;
Step (b6): Hydrothermal treatment of the stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a6) at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours. The process of performing,
Step (c6): A stannic oxide-zirconium oxide composite aqueous sol obtained in step (b6), a WO ₃ / SnO ₂ weight ratio of 0 to 100 having a particle diameter of 2 to 7 nm and 0 An aqueous sol containing tungsten oxide-stannic oxide-silicon dioxide composite colloidal particles having a SiO ₂ / SnO ₂ weight ratio of 1 to 100 was converted to its metal oxide (SnO ₂ + WO ₃ + SiO ₂ ) / (SnO ₂ + ZrO ₂ ) in a weight ratio of 0.01 to 0.50, and (d6) step: the aqueous medium obtained in step (c6) is 0.1 at 20 to 300 ° C. It is a method for producing a stable sol of modified stannic oxide-zirconium oxide composite colloidal particles including a step of aging for -50 hours.

  The present invention relates to an alkali salt of antimonic acid, an antimony pentoxide colloid containing an alkali component, a coating obtained by adding a silicon dioxide component thereto, an antimony pentoxide-silicon dioxide complex colloid, and tungsten oxide-stannic oxide-ni. Various defects (dispersibility, weather resistance, long-term stability, compatibility with hard coating agents, binding properties) of conventional metal oxide colloids can be improved by the action of coating with a silicon oxide composite colloid, An excellent modified metal oxide can be obtained. When the modified stannic oxide and / or stannic oxide-zirconium oxide composite colloid of the present invention is used as a hard coating agent component, yellowing caused by ultraviolet irradiation, which is observed when a conventional metal oxide sol is used, The problems of film hardness, water resistance, moisture resistance and compatibility can be overcome.

  The object of the present invention is to provide a stable sol of modified metal oxide colloidal particles having good water resistance and weather resistance, and the hard coat as a component for improving the performance of a hard coat film applied to the surface of a plastic lens. An object of the present invention is to provide a sol that can be mixed with a paint for use.

  The sol of the surface-modified metal oxide colloidal particles obtained by the present invention is colorless and transparent, the refractive index calculated from the dried coating film is 1.9 or more, and both the bonding strength and hardness are high. Also, weather resistance, antistatic property, heat resistance, wear resistance, etc. are good. In particular, weather resistance and moisture resistance are remarkably improved as compared with the conventional one.

  This sol is stable at a pH of 3 to 11.5 and can also provide sufficient stability to be supplied as an industrial product.

  Since the colloidal particles are negatively charged, this sol has good miscibility with sols composed of other negatively charged colloidal particles, such as silicon dioxide sol, antimony pentoxide sol, anionic or Nonionic surfactant, aqueous solution such as polyvinyl alcohol, anionic or nonionic resin emulsion, water glass, aqueous solution such as aluminum phosphate, hydrolyzed solution of ethyl silicate, silane cup such as γ-glycidoxytrimethoxysilane It can be stably mixed with a ring agent or a hydrolyzate thereof.

  The sol of the present invention having such properties has a refractive index, dyeability, chemical resistance, water resistance, moisture resistance, light resistance, weather resistance, abrasion resistance, etc. for forming a hard coat film on a plastic lens. It is particularly effective as an improving component, but can be used for various other purposes.

  By applying this sol to the surface of organic fibers, fiber products, paper, etc., the flame retardancy, anti-slip property, antistatic property, dyeability and the like of these materials can be improved. Moreover, these sols can be used as binders for ceramic fibers, glass fibers, ceramics, and the like. Furthermore, by mixing and using in various paints, various adhesives, etc., the water resistance, chemical resistance, light resistance, weather resistance, abrasion resistance, flame resistance, etc. of those cured coating films can be improved. . In addition, these sols can generally be used as surface treatment agents for metal materials, ceramic materials, glass materials, plastic materials and the like. Further, it is useful as a catalyst component.

The sol obtained according to the first aspect and the second aspect of the present invention is stannic oxide particles (A1) or stannic oxide that has been heat-treated at 100 to 350 ° C. for 0.01 to 100 hours under pressure. Composite particles of particles and zirconium oxide particles, and these oxides have a ratio of 0.001: 1 to 0.50: 1 and a particle diameter of 4 to 50 nm as ZrO ₂ : SnO ₂ based on weight. Alkylamine having a colloidal particle (A2) as a core, the surface of which has a molar ratio of M / Sb ₂ O ₅ of 0.02 to 4.00 (where M represents an amine molecule) and a particle diameter of 1 to 20 nm. Coated with Sb ₂ O ₅ colloidal particles (B1), and the weight ratio of (B1) / [(A1) or (A2)] is 0.01 to 0.50 based on the weight ratio of the metal oxides. Is a ratio, and 4.5 It is a sol containing modified metal oxide particles having a particle size of 60 nm.

Moreover, the sol obtained by the third aspect or the fourth aspect of the present invention is stannic oxide particles (A1) that have been heat-aged under pressure at 100 to 350 ° C. for 0.01 to 100 hours, or oxidized Composite particles of distinous particles and zirconium oxide particles, and these oxides are based on weight as ZrO ₂ : SnO _{2 in} a ratio of 0.001: 1 to 0.50: 1 and a particle diameter of 4 to 50 nm. A colloidal particle of antimony pentoxide and silicon dioxide having a molar ratio of SiO ₂ / Sb ₂ O ₅ of 0.55 to 55 and a particle diameter of 5 nm or less with a colloidal particle (A2) having a nucleus as a nucleus 3. coated with (B2) and the weight ratio of (B2) / [(A1) or (A2)] is a ratio of 0.01 to 0.50 based on the weight ratio of the metal oxides; 5-60nm particles Is a sol containing modified metal oxide particles have a.
And the sol obtained by the 5th viewpoint or the 6th viewpoint of this invention is 100-350 degreeC under pressurization, the heat-aged stannic oxide particle (A1) for 0.01 to 100 hours, or oxidation first Colloidal particles having stannic particles and zirconium oxide particles, these oxides having a ratio of 0.001: 1 to 0.50: 1 and a particle size of 4 to 50 nm as ZrO ₂ : SnO ₂ based on weight. Tungsten oxide, stannic oxide and dioxide containing the surface of A2) as a nucleus in a ratio of 0.1 to 100 as a weight ratio of WO ₃ / SnO _{2 and} 0.1 to 100 as a weight ratio of SiO ₂ / SnO ₂ Coated with the silicon composite colloidal particles (B3), and the weight ratio of (B3) / [(A1) or (A2)] is 0.01 to 0.50 based on the weight ratio of these metal oxides. Ah And a sol containing modified metal oxide particles having a particle size of 4.5～60Nm.

  The particle diameter in the sol is represented by the particle diameter by electron microscope observation.

  The stannic oxide colloidal particles as the core particles (A1) used for the production of the sol of the present invention are about 4 to 4 by a known method, for example, a method called ion exchange method, peptization method, hydrolysis method, reaction method or the like. It can be easily prepared in the form of a sol of colloidal particles having a particle diameter of about 50 nm.

  Examples of the ion exchange method include a method of treating a stannate such as sodium stannate with a hydrogen cation exchange resin, or a stannic salt such as stannic chloride and stannic nitrate. The method of processing with a type | mold anion exchange resin is mentioned. Examples of the peptization method include neutralizing stannic salt with a base or washing stannic hydroxide gel obtained by neutralizing stannic acid with hydrochloric acid, and then peptizing with acid or base. The method of doing is mentioned. Examples of the hydrolysis method include a method of hydrolyzing tin alkoxide or a method of removing an unnecessary acid after hydrolyzing a basic stannic chloride salt under heating. Examples of the reaction method include a method of reacting metal tin powder with an acid.

In the present invention, the stannic oxide aqueous sol having a SnO ₂ concentration of 1 to 50% by weight produced by the above method can be used as it is, but under pressure, 100 to 350 ° C., 0.01 hour to 100 It is preferable to produce by hydrothermal treatment for hours. In the hydrothermal treatment, for example, the above stannic oxide aqueous sol is placed in an autoclave and subjected to a treatment for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa (megapascal) and a temperature of 100 to 350 ° C.

  The medium of these stannic oxide sols may be either water or a hydrophilic organic solvent, but an aqueous sol in which the medium is water is preferable. The pH of the sol is good for stabilizing the sol, and is usually about 0.2 to 11.5. As long as the object of the present invention is achieved, the stannic oxide sol may contain an optional component, for example, an alkaline substance, an acidic substance, an oxycarboxylic acid and the like for stabilizing the sol. The concentration of the stannic oxide sol used is about 0.5 to 50% by weight as stannic oxide, but this concentration should be low, and preferably 1 to 30% by weight.

The stannic oxide-zirconium oxide composite sol (A2) as a core particle used for the production of the sol of the present invention has the above-mentioned oxidation having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50% by weight. The stannic sol is mixed with 0.1 to 50% by weight of oxyzirconium salt at 5 to 100 ° C. for 0.1 to 50 hours so that the weight ratio of ZrO ₂ / SnO ₂ is 0.001 to 0.5. Then, by obtaining this by a step of heating at 60 to 100 ° C. for 0.1 to 50 hours, an aqueous sol of stannic oxide-zirconium oxide composite colloid having a particle diameter of 4 to 50 nm is obtained.

  As the stannic oxide sol used here, either a sol that has been subjected to hydrothermal treatment in advance or a sol that has not been subjected to hydrothermal treatment can be used.

The aqueous sol of stannic oxide-zirconium oxide composite colloid thus obtained was
Hydrothermal treatment is performed for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.

Examples of the oxyzirconium salt include ammonium zirconyl carbonate, potassium zirconyl carbonate, zirconium oxychloride, zirconium oxynitrate, zirconium oxysulfate, zirconium oxyacetate, zirconium oxycarbonate, and the like. These oxyzirconium salts can be used as a solid or an aqueous solution, but it is preferably used as an aqueous solution of about 0.5 to 50% by weight, preferably about 0.5 to 30% by weight as ZrO2.
Further, even a salt insoluble in water, such as zirconyl oxycarbonate, can be used when stannic oxide is an acidic sol.

  As the stannic oxide sol, it is particularly preferable to use an alkaline sol stabilized with an organic base such as an amine, and mixing with the oxyzirconium salt is preferably 5 to 100 ° C., preferably room temperature (20 ° C.) to 60 ° C. . In this mixing, the oxyzirconium salt may be added to the stannic oxide sol under stirring, or the stannic oxide sol may be added to the aqueous oxyzirconium salt solution, but the latter is preferred. This mixing needs to be carried out sufficiently and is preferably 0.5 to 3 hours.

  The alkylamine-containing antimony pentoxide colloid (B1) used as the coating sol of the present invention can be obtained by the following methods (oxidation method, acid decomposition method, etc.). Examples of the acid decomposition method include a method in which an alkali antimonate is reacted with an inorganic acid and then peptized with an amine (JP 60-41536 A, JP 61-227918 A, JP 2001-123115 A), oxidation Examples of the method and a method of oxidizing antimony trioxide with hydrogen peroxide in the coexistence of an amine or an alkali metal (Japanese Patent Publication No. 57-11848, Japanese Patent Laid-Open No. 59-232921) or antimony trioxide oxidized with hydrogen peroxide Then, it can obtain by the method of adding an amine or an alkali metal.

  Examples of the amine of the above-mentioned amine-containing antimony pentoxide colloid include ammonium, quaternary ammonium and water-soluble amine. Preferred examples of these include alkylamines such as isopropylamine, diisopropylamine, n-propylamine and diisobutylamine, aralkylamines such as benzylamine, alicyclic amines such as piperidine, alkanolamines such as monoethanolamine and triethanolamine. And quaternary ammonium such as tetramethylammonium hydroxide. Particularly preferred are diisopropylamine and diisobutylamine. The molar ratio of the alkali component to the antimony pentoxide in the amine-containing antimony pentoxide colloid is preferably 0.02 to 4.00 for M / Sb2O5, and if less than this, the stability of the obtained colloid becomes poor, If the amount is too large, the water resistance of the dried coating film obtained using such a sol is lowered, which is not preferable in practice.

  The amine-containing antimony pentoxide colloidal particles (B1) are fine colloidal particles of antimony pentoxide, and the particle diameter thereof was about 1 to 20 nm in terms of oligomer or primary particle diameter by electron microscope observation. An alkylamine salt such as diisopropylamine is preferable as the amine component, and the amine / Sb2O5 molar ratio is 0.02 to 4.00.

  In the coating, alkylamine-containing silicon dioxide particles can be further added to the amine-containing antimony pentoxide colloidal particles.

  The composite colloid (B2) of antimony pentoxide and silicon dioxide used as the coating sol of the present invention can be obtained by the following known method (for example, Japanese Patent Publication No. 50-40119). That is, it can be obtained by mixing an alkali silicate aqueous solution or a silicic acid solution and an alkali antimonate aqueous solution and then decationizing with a cation exchange resin.

As the antimony raw material, a potassium antimonate aqueous solution can be preferably used. As the silicon dioxide raw material, sodium silicate, potassium silicate, and activated silicic acid obtained by cation exchange thereof can be used. The molar ratio of SiO ₂ / _Sb 2 _{O 5} is from 0.55 to 55. The particle diameter is 5 nm or less, preferably 1 to 5 nm for oligomers or primary particles by electron microscope observation.

Tungsten oxide, stannic oxide, and silicon dioxide composite colloidal particles (B3) used in the coating sol of the present invention can be obtained by the following method.
An aqueous solution containing tungstate, stannate and silicate in a ratio of 0.1 to 100 as a WO ₃ / SnO ₂ weight ratio and 0.1 to 100 as a SiO ₂ / SnO ₂ weight ratio is prepared and obtained. It is obtained by a method of removing cations present in an aqueous solution.
The total concentration of WO ₃ , SnO ₂ and SiO ₂ contained in the sol is usually 40% by weight or less, preferably 2% by weight or more, and preferably 5 to 30% by weight in practice.

As long as the objective of this invention is achieved, it can contain other arbitrary components. In particular, when oxycarboxylic acids are contained in an amount of about 30% by weight or less based on the total amount of WO ₃ , SnO ₂ and SiO ₂ , a further improved sol can be obtained. Examples of the oxycarboxylic acid used include lactic acid, tartaric acid, citric acid, gluconic acid, malic acid, glycolic acid and the like.

It can exist stably without substantially containing an alkali component. However, it is also possible to stabilize by containing an alkali component. The alkali component includes alkali metal hydroxides such as Li, Na, K, Rb, and Cs, alkylamines such as NH ₄ , ethylamine, triethylamine, isopropylamine, and n-propylamine; aralkylamines such as benzylamine; piperidine, and the like And alkanolamines such as monoethanolamine and triethanolamine. These alkali components can be contained in an amount of about 30% by weight or less based on the total amount of WO ₃ , SnO ₂ and SiO ₂ . Moreover, these can mix and contain 2 or more types.

  This sol is a liquid having a pH of 1 to 9 and having a colorless and transparent or slightly colloidal color. It is stable for 3 months or more at room temperature, and stable for 1 month or more at 60 ° C., and no precipitate is generated in the sol, and the sol does not thicken or cause gelation. .

Examples of tungstates, stannates and silicates used in the production of this sol include the tungstates such as alkali metals, ammonium and amines, stannates and silicates. In particular, sodium tungstate (Na ₂ WO ₄ · 2H ₂ O), sodium stannate (Na ₂ SnO ₃ · 3H ₂ O) and sodium silicate (water glass) are preferable. Also. A solution in which tungsten oxide, tungstic acid, stannic acid, silicic acid, or the like is dissolved in an aqueous solution of an alkali metal hydroxide can also be used. A method for preparing an aqueous solution by dissolving each powder of tungstate, stannate, and silicate in water, a method for preparing an aqueous solution by mixing an aqueous solution of tungstate, an aqueous solution of stannate, and an aqueous solution of silicate, Examples thereof include a method of preparing an aqueous solution by adding a tungstate and stannate powder and an aqueous solution of silicate to water. The aqueous solution of tungstate is preferably 0.1 to 15% by weight as WO ₃ but can be used at higher concentrations. As an aqueous solution of stannate, a SnO ₂ concentration of about 0.1 to 30% by weight is preferable, but a concentration higher than this can also be used. The aqueous silicate solution preferably has a SiO ₂ concentration of about 0.1 to 30% by weight, but can be used at a higher concentration.

The aqueous solution is preferably prepared at room temperature to 100 ° C., preferably at room temperature to 60 ° C. with stirring. The aqueous solution to be mixed preferably has a WO ₃ / SnO ₂ weight ratio of 0.1 to 100 and a SiO ₂ / SnO ₂ weight ratio of 0.1 to 100. Subsequently, the cation present in the aqueous solution obtained here is removed to obtain an aqueous sol. As a method of decation treatment, a method of contacting with a hydrogen ion exchanger or salting out can be performed. The hydrogen-type cation exchanger used here is usually used, and a commercially available hydrogen-type cation exchange resin can be conveniently used.

When the concentration of the sol is low, the concentration of the sol can be increased by a normal concentration method such as an evaporation method or an ultrafiltration method, if desired. In particular, the ultrafiltration method is preferable. Also in this concentration, the temperature of the sol is preferably kept at about 100 ° C. or less, particularly 60 ° C. or less.
The modified stannic oxide or modified stannic oxide-zirconium oxide composite colloidal particles coated with the amine-containing Sb ₂ O ₅ colloid (B1) according to the present invention are negatively charged in the sol. Yes.

The stannic oxide (A1) and the stannic oxide-zirconium oxide composite colloidal particles (A2) are positively charged, and the Sb ₂ O ₅ colloid is negatively charged. Accordingly, the positively charged colloidal particles of stannic oxide or stannic oxide-zirconium oxide composite colloidal particles are electrically attracted to the negatively charged colloidal particles of Sb ₂ O ₅ and positively charged. Sb ₂ O ₅ colloids are bonded to the surface of the charged colloidal particles by chemical bonds, and the positively charged particles are used as nuclei to cover the surface of the negatively charged Sb ₂ O _5. It is considered that stannic-zirconium oxide composite colloidal particles were produced.

When mixing stannic oxide or stannic oxide-zirconium oxide composite colloidal particles having a particle diameter of 4 to 50 nm as a core sol and an amine-containing Sb ₂ O ₅ colloid (B1) as a coating sol, When the amount of the metal oxide of the coating sol is less than 1 part by weight with respect to 100 parts by weight of the metal oxide (SnO ₂ or ZrO ₂ + SnO ₂ ) of the sol, a stable sol cannot be obtained. This means that when the amount of colloid of Sb ₂ O ₅ is insufficient, the coating of the surface of the composite with the stannic oxide-zirconium oxide composite colloid particles becomes insufficient, and the resulting colloid Aggregation of particles is likely to occur, and it is thought that the generated sol is unstable. Accordingly, the amount of Sb ₂ O ₅ colloidal particles to be mixed may be less than the amount covering the entire surface of the stannic oxide-zirconium oxide composite colloidal particles, but stable modified stannic oxide or oxidation. The amount is more than the minimum amount necessary to form a sol of colloidal particles of stannic-zirconium oxide composite. When an amount of Sb ₂ O ₅ colloidal particles that exceeds the amount used for this surface coating is used for the above mixing, the resulting sol is composed of the Sb ₂ O ₅ colloidal sol and the resulting modified stannic oxide. Or it is only a stable mixed sol of sols of colloidal particles of stannic oxide-zirconium oxide composites.

Preferably, to modify the stannic oxide or stannic oxide-zirconium oxide composite colloidal particles by their surface coating, the amount of colloid (B1) of Sb ₂ O ₅ used depends on the metal oxide of the core sol 50 parts by weight or less is preferable as a metal oxide in the coating sol with respect to 100 parts by weight of (SnO ₂ or ZrO ₂ + SnO ₂ ).

  The modified stannic oxide or modified stannic oxide-zirconium oxide composite colloidal particles coated with antimony pentoxide and silicon dioxide composite colloid (B2) according to the present invention are negative in the sol. Is charged.

  The stannic oxide or stannic oxide-zirconium oxide composite colloidal particles are positively charged, and the composite colloid of antimony pentoxide and silicon dioxide is negatively charged. Therefore, the composite colloid of antimony pentoxide and silicon dioxide that is negatively charged around the positively charged stannic oxide or stannic oxide-zirconium oxide composite colloidal particles by mixing is electrically The colloid of the composite colloid of antimony pentoxide and silicon dioxide is bonded to the surface of the positively charged colloidal particle by chemical bond, and the surface of the positively charged particle is used as a nucleus to negatively charge the surface. It is considered that the modified colloidal particles of stannic oxide or stannic oxide-zirconium oxide composite were formed by covering the composite colloid of antimony and silicon dioxide.

Mix stannic oxide or stannic oxide-zirconium oxide composite colloidal particles having a particle diameter of 4 to 50 nm as a core sol and antimony pentoxide and silicon dioxide composite colloid (B2) as a coating sol. Sometimes, if the amount of the metal oxide in the coating sol is less than 1 part by weight with respect to 100 parts by weight of the metal oxide (SnO ₂ or ZrO ₂ + SnO ₂ ) in the core sol, a stable sol cannot be obtained. This means that when the amount of antimony pentoxide and silicon dioxide complex colloid is insufficient, the colloidal particles of this complex are stannic oxide or stannic oxide-zirconium oxide complex colloidal particles. It is considered that the surface coating becomes insufficient, the resulting colloidal particles tend to aggregate, and the resulting sol becomes unstable. Therefore, the amount of antimony pentoxide and silicon dioxide composite colloidal particles to be mixed may be less than the amount covering the entire surface of stannic oxide or stannic oxide-zirconium oxide composite colloidal particles, The amount is more than the minimum amount necessary to form a sol of stable modified stannic oxide-zirconium oxide composite colloidal particles. When an amount of antimony pentoxide and silicon dioxide composite colloidal particles exceeding the amount used for this surface coating was used for the above mixing, the resulting sol was composed of the composite colloid of antimony pentoxide and silicon dioxide. It is just a stable mixed sol of the sol and the resulting modified stannic oxide or sol of stannic oxide-zirconium oxide composite colloidal particles.

Preferably, to modify the stannic oxide or stannic oxide-zirconium oxide composite colloidal particles by their surface coating, the amount of antimony pentoxide and silicon dioxide composite colloid (B2) used is 50 parts by weight or less is preferable as the metal oxide in the coating sol with respect to 100 parts by weight of the metal oxide (SnO ₂ or ZrO ₂ + SnO ₂ ) of the sol.
The modified stannic oxide or modified stannic oxide-zirconium oxide composite colloidal particles coated with the tungsten oxide / stannic oxide / silicon dioxide composite colloid (B3) according to the present invention are: It is negatively charged in the sol.

  The stannic oxide or stannic oxide-zirconium oxide composite colloidal particles are positively charged, and the composite colloid of tungsten oxide, stannic oxide and silicon dioxide is negatively charged. Therefore, a composite of tungsten oxide, stannic oxide and silicon dioxide negatively charged around the positively charged stannic oxide or stannic oxide-zirconium oxide composite colloidal particles by mixing. The colloid is electrically attracted, and a composite colloid of tungsten oxide, stannic oxide and silicon dioxide is bonded to the surface of the positively charged colloidal particle by chemical bonding, and the surface of the positively charged particle is used as a nucleus. The negatively charged tungsten oxide, stannic oxide, and silicon dioxide composite colloids are covered, resulting in modified stannic oxide or stannic oxide-zirconium oxide composite colloidal particles. Conceivable.

Stannic oxide or stannic oxide-zirconium oxide composite colloidal particles having a particle diameter of 4 to 50 nm as a core sol, and a composite colloid of tungsten oxide, stannic oxide and silicon dioxide as a coating sol (B3) When the amount of the metal oxide of the coating sol is less than 1 part by weight with respect to 100 parts by weight of the metal oxide (SnO ₂ or ZrO ₂ + SnO ₂ ) of the core sol, a stable sol cannot be obtained. This means that when the amount of the composite colloid of tungsten oxide, stannic oxide, and silicon dioxide is insufficient, stannic oxide or stannic oxide-zirconium oxide composite colloidal particles by colloidal particles of this composite are used. It is thought that the coating on the surface of the core becomes insufficient, the resulting colloidal particles tend to aggregate, and the resulting sol becomes unstable. Therefore, the amount of the tungsten oxide / stannic oxide / silicon dioxide composite colloidal particles to be mixed is less than the amount covering the entire surface of the stannic oxide or stannic oxide-zirconium oxide composite colloidal particles. However, the amount is more than the minimum amount necessary to form a sol of stable modified stannic oxide or stannic oxide-zirconium oxide composite colloidal particles. When composite colloidal particles of tungsten oxide, stannic oxide, and silicon dioxide exceeding the amount used for the surface coating are used for the above mixing, the resulting sol is composed of antimony pentoxide and silicon dioxide. It is only a stable mixed sol of the composite colloid sol and the resulting modified stannic oxide or stannic oxide-zirconium oxide composite colloid particle sol.

Preferably, in order to modify the stannic oxide or stannic oxide-zirconium oxide composite colloidal particles by its surface coating, the composite colloid (B3) of tungsten oxide, stannic oxide and silicon dioxide used is used. The amount is preferably 50 parts by weight or less as the metal oxide in the coating sol with respect to 100 parts by weight of the metal oxide (SnO ₂ or ZrO ₂ + SnO ₂ ) in the core sol.

In the present invention, when stannic oxide is used for the nucleus,
(A1) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight,
(B1) step: a step of aging the stannic oxide aqueous sol obtained in the step (a1) at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours;
Step (c1): The molar ratio of the stannic oxide aqueous sol obtained in Step (b1) to M / Sb ₂ O ₅ of 0.02 to 4.00 (where M represents an amine molecule) and A step of mixing an alkylamine-containing Sb ₂ O ₅ aqueous sol having a particle diameter of 1 to 20 nm with a weight ratio of Sb ₂ O ₅ / SnO ₂ converted to the metal oxide to 0.01 to 0.50 ( d1) Step: A method for producing a stable sol of modified stannic oxide colloidal particles, comprising the step of aging the aqueous medium obtained in step (c) at 20 to 300 ° C. for 0.1 to 50 hours.
When the sol obtained in step (d1) contains an anion, step (e1) can be added. That is, the step (e1) removes anions present in the sol by contacting the modified stannic oxide aqueous sol obtained in the step (d1) with an anion exchanger, and then 20 to A stable sol of modified stannic oxide colloidal particles is obtained by adding a step of aging at 300 ° C. for 0.1 to 50 hours. Aging at 100 ° C. or higher can be performed using an autoclave. This sol has a molar ratio of M / Sb ₂ O ₅ of which the surface is 0.02 to 4.00 with stannic oxide colloidal particles (A1) having a particle diameter of 4 to 50 nm as the core (where M is an amine molecule). ) And alkylamine-containing Sb ₂ O ₅ colloidal particles (B1) having a particle diameter of 1 to 20 nm, and the weight ratio of (B1) / (A1) is based on the weight ratio of these metal oxides. A sol containing modified stannic oxide particle colloidal particles in a proportion of 0.01 to 0.50 and having a particle size of 4.5 to 60 nm.

In the present invention, when colloidal particles of stannic oxide and zirconium oxide are used for the core, the step (a2): oxidation step having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50% by weight. two tin aqueous sol, an aqueous solution of oxyzirconium salt of from 0.1 to 50% by weight concentration in terms of ZrO _2, were mixed in a weight ratio of ZrO 2 / SnO ₂ as 0.001 to 0.50, give A step of preparing a stannic oxide-zirconium oxide composite aqueous sol having a particle diameter of 4 to 50 nm by heating the obtained mixed liquid at 60 to 100 ° C. for 0.1 to 50 hours;
(B2) Step: The stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a2) is aged at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours. Process,
Step (c2): Molar ratio of stannic oxide-zirconium oxide composite aqueous sol obtained in step (b2) and M2 / Sb ₂ O ₅ of 0.02 to 4.00 (where M is an amine molecule) And an alkylamine-containing Sb ₂ O ₅ aqueous sol having a particle diameter of 1 to 20 nm in a weight ratio of Sb ₂ O ₅ / (SnO ₂ + ZrO ₂ ) in terms of the metal oxide is 0.01 to Mixing to 0.50,
Step (d2): A stable sol of modified stannic oxide-zirconium oxide composite colloidal particles comprising the step of aging the aqueous medium obtained in Step (c2) at 20 to 300 ° C. for 0.1 to 50 hours Manufacturing method.
The sol is composed of stannic oxide particles and zirconium oxide particles having an oxide ratio of ZrO ₂ : SnO ₂ of 0.05: 1 to 0.50: 1 and a particle diameter of 4 to 50 nm based on weight. The surface of the composite colloidal particle (A2) as a nucleus has a molar ratio of M / Sb ₂ O ₅ of 0.02 to 4.00 (where M represents an amine molecule) and a particle diameter of 1 to 20 nm. Coated with alkylamine-containing Sb ₂ O ₅ colloidal particles (B1), and the weight ratio of (B1) / (A) is a ratio of 0.01 to 0.50 based on the weight ratio of the metal oxides; The sol contains composite colloidal particles of modified stannic oxide particles and zirconium oxide particles having a particle diameter of 4.5 to 60 nm.
When the sol obtained in step (d2) contains an anion, step (e2) can be added. That is, in step (e2), the modified stannic oxide aqueous sol obtained in step (d2) is contacted with an anion exchanger to remove anions present in the sol, and then 20 to A stable sol of modified stannic oxide-zirconium oxide composite colloidal particles is obtained by adding a step of aging at 300 ° C. for 0.1 to 50 hours. Aging at 100 ° C. or higher can be performed using an autoclave. This sol is composed of stannic oxide-zirconium oxide composite colloidal particles (A2) having a particle diameter of 4 to 50 nm as a nucleus and a molar ratio of M / Sb ₂ O ₅ having a surface of 0.02 to 4.00 ( M represents an amine molecule.) And an alkylamine-containing Sb ₂ O ₅ colloidal particle (B1) having a particle diameter of 1 to 20 nm, and the weight ratio of (B1) / (A2) is the metal oxide. Containing a composite colloidal particle of modified stannic oxide particles and zirconium oxide particles having a particle size of 4.5 to 60 nm, based on a weight ratio of 0.01 to 0.50 It is a sol.
Moreover, when using the aqueous sol in which the coating contains composite colloidal particles of antimony pentoxide and silicon dioxide, step (a3): stannic oxide colloidal particles having a particle diameter of 4 to 50 nm as SnO ₂ A step of preparing a stannic oxide aqueous sol contained at a concentration of 1 to 50% by weight, step (b3): the stannic oxide aqueous sol obtained in the step (a3) is subjected to a pressure of 0.1 to 40 MPa; Step of aging for 0.01 to 100 hours at a temperature of 100 to 350 ° C., step (c3): stannic oxide aqueous sol obtained in the step (b3), and SiO ₂ / Sb of 0.55 to 55 An aqueous sol containing a composite colloidal particle of antimony pentoxide and silicon dioxide having a molar ratio of ₂ O ₅ and a particle diameter of 5 nm or less was converted into its metal oxide (Sb ₂ O ₅ + SiO ₂ ) / (Sn A step of mixing 0.01 to 0.50 at a weight ratio of O ₂ ), and a step (d3): a step of aging the aqueous medium obtained in the step (c3) at 20 to 300 ° C. for 0.1 to 50 hours Is a method for producing a stable sol of modified stannic oxide colloidal particles.

When the sol obtained in step (d3) contains an anion, step (e3) can be added. That is, in the step (e3), the modified stannic oxide aqueous sol obtained in the step (d3) is contacted with an anion exchanger to remove anions present in the sol, and then 20 to A stable sol of modified stannic oxide colloidal particles is obtained by adding a step of aging at 300 ° C. for 0.1 to 50 hours. Aging at 100 ° C. or higher can be performed using an autoclave. This sol has a tantalum oxide colloidal particle (A1) having a particle diameter of 4 to 50 nm as a nucleus, and the surface has a SiO ₂ / Sb ₂ O ₅ molar ratio of 0.55 to 55 and a particle diameter of 5 nm or less. The composite colloidal particles (B2) of antimony pentoxide and silicon dioxide having a weight ratio of (B2) / (A1) of 0.01 to 0.50 based on the weight ratio of the metal oxides. A sol containing modified stannic oxide particles in proportion and having a particle size of 4.5-60 nm.
Further, when an aqueous sol containing a composite colloidal particle of antimony pentoxide and silicon dioxide is used as the coating, step (a4): a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50% by weight are used. mixing a stannic oxide aqueous sol having, an aqueous solution of oxyzirconium salt of from 0.1 to 50% by weight concentration in terms of ZrO _2, the weight ratio of ZrO 2 / SnO ₂ as 0.001 to 0.50 A step of preparing an aqueous sol of stannic oxide-zirconium oxide composite colloid having a particle size of 4 to 50 nm by heating the obtained mixed liquid at 60 to 100 ° C. for 0.1 to 50 hours, Step (b4): Hydrothermal heat of the stannic oxide-zirconium oxide composite aqueous sol obtained in step (a4) at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours A step of performing management, (c4) step: (b4) stannic oxide obtained in step - zirconium oxide composite aqueous sol, the molar ratio of _SiO 2 / _Sb 2 _{O 5} of 0.55 to 55 and 5nm or less (Sb ₂ O ₅ + SiO ₂ ) / (SnO ₂ + ZrO ₂ ) weight ratio of an aqueous sol containing a composite colloidal particle of antimony pentoxide and silicon dioxide having a particle size of The step of mixing at 0.01 to 0.50, the step of combining, the step (d4): the step of aging the aqueous medium obtained in the step (c4) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of colloidal stannic oxide-zirconium oxide particles.

When the sol obtained in step (d4) contains an anion, step (e4) can be added. That is, the step (e4) is present in the sol by bringing the aqueous sol of the modified stannic oxide-zirconium oxide composite colloidal particles obtained in the step (d4) into contact with the anion exchanger. A stable sol of modified stannic oxide-zirconium oxide composite colloidal particles can be obtained by adding an additional step of removing anions and then aging at 20 to 300 ° C. for 0.1 to 50 hours. Aging at 100 ° C. or higher can be performed using an autoclave. This sol is composed of stannic oxide-zirconium oxide composite colloidal particles (A2) having a particle diameter of 4 to 50 nm as a nucleus, and the surface thereof has a molar ratio of SiO ₂ / Sb ₂ O ₅ of 0.55 to 55. It is coated with a composite colloidal particle (B2) of antimony pentoxide and silicon dioxide having a particle diameter of 5 nm or less, and the weight ratio of (B2) / (A2) is 0. 0 based on the weight ratio of these metal oxides. A sol containing modified stannic oxide-zirconium oxide composite colloidal particles in a proportion of 01-0.50 and having a particle size of 4.5-60 nm.

When the coating uses a tungsten oxide-stannic oxide-silicon dioxide composite aqueous sol, the step (a5): stannic oxide colloidal particles having a particle diameter of 4 to 50 nm are used as SnO ₂ and 1 to A step of preparing a stannic oxide aqueous sol contained in a concentration of 50% by weight, step (b5): the stannic oxide aqueous sol obtained in the step (a5) is subjected to a pressure of 0.1 to 40 MPa and 100 to 100 A step of hydrothermal treatment at a temperature of 350 ° C. for 0.01 to 100 hours, a step (c5): a stannic oxide aqueous sol obtained in the step (b5), and a particle size of 2 to 7 nm; A tungsten oxide-stannic oxide-silicon dioxide composite aqueous sol having a WO ₃ / SnO ₂ weight ratio of 1 to 100 and a SiO ₂ / SnO ₂ weight ratio of 0.1 to 100 is converted into its metal oxide. the _(SnO 2 + O ₃ + _SiO 2) / (step mixing SnO ₂₎ 0.01 to 0.50 in weight ratio, and (d5) step: (c5) the aqueous medium obtained in step at 20 to 300 ° C. 0. It is a method for producing a stable sol of modified stannic oxide colloidal particles comprising a step of aging for 1 to 50 hours.

When the sol obtained in step (d5) contains an anion, step (e5) can be added. That is, in the step (e5), the aqueous sol of the modified stannic oxide composite colloidal particles obtained in the step (d5) is brought into contact with an anion exchanger, so that the anion present in the sol is removed. A stable sol of modified stannic oxide colloidal particles is obtained by adding a step of removing and then aging at 20 to 300 ° C. for 0.1 to 50 hours. Aging at 100 ° C. or higher can be performed using an autoclave. This sol has a WO ₃ / SnO ₂ weight ratio of 0.1 to 100 with a surface having a particle diameter of 2 to 7 nm with stannic oxide colloidal particles (A1) having a particle diameter of 4 to 50 nm as nuclei. tungsten oxide having a _SiO 2 / SnO ₂ weight ratio of 0.1 to 100 - stannic oxide - coated with silicon dioxide composite colloidal particles (B3), and (B3) / weight ratio of (A1) is such a metal A sol containing modified stannic oxide colloidal particles in a proportion of 0.01 to 0.50 based on the weight ratio of the oxide and having a particle size of 4.5 to 60 nm.

When the coating uses a tungsten oxide-stannic oxide-silicon dioxide composite aqueous sol, the step (a6): oxidation having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50% by weight. a stannic aqueous sol, an aqueous solution of oxyzirconium salt of from 0.1 to 50% by weight concentration in terms of ZrO _2, were mixed in a weight ratio of ZrO 2 / SnO ₂ as 0.001 to 0.50, A step of preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 4 to 50 nm by heating the obtained mixed liquid at 60 to 100 ° C. for 0.1 to 50 hours, (b6 ) Step: The stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a6) is subjected to hydrothermal treatment for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. Extent, (c6) step: (b6) stannic oxide obtained in the step - zirconium oxide composite aqueous sol, _WO 3 / SnO ₂ weight ratio of 0.1 to 100 have a particle size of 2~7nm And a tungsten oxide-stannic oxide-silicon dioxide composite aqueous sol having a SiO ₂ / SnO ₂ weight ratio of 0.1 to 100 are converted into their metal oxides (SnO ₂ + WO ₃ + SiO ₂ ) / ( Step of mixing 0.01 to 0.50 by weight ratio of SnO ₂ + ZrO ₂ ), step (d6): aging the aqueous medium obtained in step (c6) at 20 to 300 ° C. for 0.1 to 50 hours A process for producing a stable sol of modified stannic oxide-zirconium oxide colloidal particles comprising a step.

When the sol obtained in step (d6) contains an anion, step (e6) can be added. That is, the step (e6) is present in the sol by bringing the aqueous sol of the modified stannic oxide-zirconium oxide composite colloidal particles obtained in the step (d6) into contact with an anion exchanger. A stable sol of modified stannic oxide-zirconium oxide composite colloidal particles can be obtained by adding an additional step of removing anions and then aging at 20 to 300 ° C. for 0.1 to 50 hours. Aging at 100 ° C. or higher can be performed using an autoclave. This sol has a stannic oxide-zirconium oxide composite colloidal particle (A2) having a particle diameter of 4 to 50 nm as a nucleus, and its surface has a particle diameter of 2 to 7 nm and WO _{3 of} 0.1 to 100. Coated with tungsten oxide-stannic oxide-silicon dioxide composite colloidal particles (B3) having a / SnO ₂ weight ratio and a SiO ₂ / SnO ₂ weight ratio of 0.1 to 100, and (B3) / (A2) Modified stannic oxide-zirconium oxide composite colloid with a weight ratio of 0.01 to 0.50 based on the weight ratio of the metal oxides and having a particle size of 4.5 to 60 nm A sol containing particles.

  In the production method for obtaining the sol of the present invention, there are a case where the particles used for the core are stannic oxide and a case where a stannic oxide and zirconium oxide composite sol is used. The former has a rutile-type crystal structure, and those sols applied to a substrate as a coating composition and baked have a high refractive index (refractive index calculated from the coating film of 1.9 or more) and excellent transparency. Have sex. In addition to the former performance, the latter has excellent weather resistance (light) performance by compounding zirconium oxide.

  The modified aqueous sol of colloidal stannic oxide particles or the aqueous sol of modified stannic oxide-zirconium oxide composite colloid according to the present invention has a pH of 3 to 11.5, and if the pH is lower than 3, such sol The sol tends to be unstable. Further, when the pH exceeds 11.5, the modified stannic oxide colloid, the modified antimony pentoxide colloid particles covering the modified stannic oxide-zirconium oxide composite colloid particles, antimony pentoxide and nickel The composite colloidal particles of silicon oxide and the composite colloidal particles of tungsten oxide, stannic oxide and silicon dioxide are easily dissolved in the liquid. Furthermore, when the total concentration of all metal oxides in the sol of the modified stannic oxide colloid and the modified stannic oxide-zirconium oxide composite colloidal particles exceeds 60% by weight, such sol Prone to instability. A preferable concentration for industrial products is about 10 to 50% by weight.

The modified metal oxide sol of the present invention can contain other optional components as long as the object of the present invention is achieved. Particularly when oxycarboxylic acids are contained in an amount of about 30% by weight or less based on the total amount of all metal oxides, a colloid with further improved performance such as dispersibility can be obtained. Examples of the oxycarboxylic acid used include lactic acid, tartaric acid, citric acid, gluconic acid, malic acid, glycol and the like. Moreover, it can contain an alkali component, for example, alkali metal hydroxides such as Li, Na, K, Rb, and Cs, alkylamines such as NH ₄ , ethylamine, triethylamine, isopropylamine, and n-propylamine; benzyl Aralkylamines such as amines; alicyclic amines such as piperidine; alkanolamines such as monoethanolamine and triethanolamine. These can contain 2 or more types in mixture. Moreover, it can use together with said acidic component. These can be contained in an amount of about 30% by weight or less based on the total amount of all metal oxides.

  When it is desired to further increase the sol concentration, it can be concentrated to a maximum of about 60% by weight by a conventional method such as an evaporation method or an ultrafiltration method. When it is desired to adjust the pH of the sol, the alkali metal, organic base (amine), oxycarboxylic acid or the like can be added to the sol after concentration. In particular, a sol having a total concentration of metal oxides of 10 to 40% by weight is practically preferable. When the ultrafiltration method is used as the concentration method, polyanions coexisting in the sol, ultrafine particles, etc. pass through the ultrafiltration membrane together with water, so these polyanions that cause destabilization of the sol, Very fine particles and the like can be removed from the sol.

  When the modified metal oxide colloid obtained by the above mixing is an aqueous sol, an organosol can be obtained by replacing the aqueous medium of the aqueous sol with a hydrophilic organic solvent. This substitution can be performed by a usual method such as a distillation method or an ultrafiltration method. Examples of the hydrophilic organic solvent include lower alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; linear amides such as dimethylformamide and N, N′-dimethylacetamide; cyclic amides such as N-methyl-2-pyrrolidone And glycols such as ethyl cellosolve and ethylene glycol.

Preparation of nuclear sol A-1 Manufacture of stannic oxide sol 37.5 kg of oxalic acid ((COOH) ₂ · 2H ₂ O) was dissolved in 383 kg of pure water, taken into a 500 L vessel, and heated to 70 ° C. with stirring. Then, 150 kg of 35% hydrogen peroxide water and 75 kg of metal tin (AT-SNNO200N manufactured by Yamaishi Metal Co., Ltd.) were added.
Hydrogen peroxide solution and metal tin were added alternately. First, 10 kg of 35% hydrogen peroxide solution was added, and then 5 kg of metallic tin. This operation was repeated after the reaction was completed (5 to 10 minutes). After the total amount was added, 10 kg of 35% hydrogen peroxide water was further added. The time required for the addition was 2.5 hours. After the addition was completed, the reaction was further completed by heating at 95 ° C. for 1 hour. The molar ratio of the hydrogen peroxide solution and metal tin was 2.61 as H ₂ O ₂ / Sn.
The obtained tin oxide sol had very good transparency. The yield of the tin oxide sol was 630 kg, the specific gravity was 1.154, the pH was 1.51, and the SnO ₂ content was 14.7% by weight.
When the obtained sol was observed with an electron microscope, it was 10 to 15 nm spherical particles with good dispersibility. This sol showed a tendency to thicken slightly when left standing, but gelation was not observed when it was left at room temperature for 6 months and was stable.
231 kg of 35% hydrogen peroxide solution and 52 kg of pure water were added to 629 kg of the obtained sol, 10 wt% as SnO ₂ , and a molar ratio of H ₂ O ₂ / (COOH) _{2 to} oxalic acid at the time of charging was 8.0. Then, the mixture was heated to 95 ° C. and aged for 5 hours. Oxalic acid contained by this operation was decomposed into carbon dioxide gas and water by reaction with hydrogen peroxide. After cooling the obtained stannic oxide slurry to about 40 ° C., 2.7 kg of isopropylamine was added and peptized, and then a catalyst tower packed with about 15 L of platinum-based catalyst {N-220 (manufactured by Sud Chemie Catalysts)) The solution was passed through and circulated to decompose excess hydrogen peroxide. The flow rate is about 30 L / min. And circulated for 5 hours. Further, the solution was passed through a column packed with an anion exchange resin (Amberlite IRA-410) to obtain 1545 kg of an alkaline tin oxide sol. The specific surface area of the obtained sol was 121 m ² / g.
B. Preparation of coating B-1-1 Preparation of alkali component-containing antimony pentoxide colloid 12.5 kg of antimony trioxide (manufactured by Guangdong Mikuni, containing 99.5% as Sb ₂ O ₃ ) in a 100 liter vessel. 66.0 kg of pure water and 12.5 kg of potassium hydroxide (containing 95% as KOH) were added, and 8.4 kg of 35% hydrogen peroxide was gradually added under stirring. The obtained aqueous potassium antimonate solution was 15.25 wt% as Sb ₂ O ₅ , 5.36 wt% as potassium hydroxide, and the molar ratio of K ₂ O / Sb ₂ O ₅ was 1.0.

The obtained aqueous solution of potassium antimonate was diluted to 2.5% by weight and passed through a column packed with a hydrogen-type cation exchange resin. To the antimonic acid solution after the ion exchange, 6.6 kg of diisopropylamine was added with stirring to obtain an alkali component-containing antimony pentoxide colloidal solution. The concentration is 1.8% by weight as Sb ₂ O ₅ , 1.2% by weight as diisopropylamine, the molar ratio of diisopropylamine / Sb ₂ O ₅ is 1.69, and the primary particle diameter is 1 as observed with a transmission electron microscope. -10 nm.
B-1-2 Preparation of alkali component-containing antimony pentoxide colloid 12.5 kg of antimony trioxide (manufactured by Guangdong Mikuni, containing 99.5% as Sb ₂ O ₃ ) in 100 liter vessel, pure water 66. 0 kg and 12.5 kg of potassium hydroxide (containing 95% as KOH) were added, and 8.4 kg of 35% hydrogen peroxide was gradually added under stirring. The obtained aqueous potassium antimonate solution was 15.25 wt% as Sb ₂ O ₅ , 5.36 wt% as potassium hydroxide, and the molar ratio of K ₂ O / Sb ₂ O ₅ was 1.0.

The obtained aqueous solution of potassium antimonate (17.6 kg) was diluted to 2.2% by weight and passed through a column filled with a hydrogen-type cation exchange resin. To the antimonic acid solution after the ion exchange, 0.25 kg of diisobutylamine was added with stirring to obtain an alkali component-containing antimony pentoxide colloidal solution. Concentration is 1.8% by weight as Sb ₂ O ₅ , 1.36% by weight as diisobutylamine, the molar ratio of diisopropylamine / Sb ₂ O ₅ is 1.79, and the primary particle diameter is 1 by observation with a transmission electron microscope. -10 nm.
B-2-1 Preparation of antimony pentoxide-silicon dioxide complex colloid 546 g of an aqueous potassium silicate solution (containing 15.4 wt% as SiO ₂ ) was diluted with 542 g of pure water, and then antimonic acid was stirred. A potassium aqueous solution (containing 14.6% by weight as Sb ₂ O ₅ ) was mixed and stirred for 1 hour to obtain a mixed aqueous solution of potassium silicate and potassium antimonate.

  The obtained mixed aqueous solution of potassium silicate and potassium antimonate is diluted with pure water to 5% by weight, and then passed through a column filled with a cation type ion exchange resin, whereby antimony pentoxide-silicon dioxide. A composite colloid was obtained.

B-3-1 Preparation of colloidal tungsten oxide-stannic oxide-silicon dioxide composite colloid 38.9 kg of silica (containing 29.3 wt% as SiO ₂ ) 38.9 kg was dissolved in 830 kg of pure water, then tungsten Sodium salt Na ₂ WO ₄ · 2H ₂ O (containing 69.8% by weight as WO ₃ ) 12.2 kg and sodium stannate NaSnO ₃ · H ₂ O (containing 55.7% by weight as SnO ₂ ) 15.3 kg Dissolve. Next, this was passed through a column of a hydrogen type cation exchange resin (IR-120B), whereby an acidic tungsten oxide-stannic oxide-silicon dioxide composite sol (pH 2.2, 0.7 wt% as WO ₃₎ , SnO ₂ as 0.7 wt%, containing 0.9 wt% as SiO _2, WO 3 / SnO ₂ weight ratio of _1.0, was SiO 2 / SnO ₂ weight ratio 1.33.) was obtained 1201kg .

Example 1
Step (a): An alkaline stannic oxide aqueous sol (A-1) having a particle diameter of 15 nm or less and an SnO ₂ concentration of 3.7% by weight was obtained.
(B) Process: The alkaline stannic oxide sol 2000 kg obtained in the (a) process was heat-treated at a processing temperature of 310 ° C., a processing pressure of 20 MPa (megapascal), and an average flow rate of 538 g / ml. The specific surface area was 61 m ² / g.
Subsequently, desalting treatment was performed at room temperature using an ultrafiltration membrane filtration apparatus. The obtained oxidized varnish sol had a specific gravity of 1.064, a pH of 9.98, and a SnO ₂ concentration of 11.7%.
Step (c): Stir 22.2 kg of the amine component-containing antimony pentoxide colloid prepared in B-1-2 to 62 kg of the aqueous sol obtained in step (b) (containing 7.25 kg as SnO ₂ ). was added under mixing to the metal oxide was converted to (B-1-2) / SnO ₂ in weight ratio 0.055.
Step (d): The aqueous medium obtained in Step (c) was aged by heating at 95 ° C. for 2 hours.
Subsequently, the obtained aqueous medium was packed in a column packed with a hydroxyl group anion exchange resin. The obtained stannic oxide aqueous sol (dilute liquid) coated with antimony pentoxide was concentrated at room temperature with a filtration device of an ultrafiltration membrane having a fractional molecular weight of 100,000, and coated with high concentration of antimony pentoxide. 26.1 kg of stannic oxide aqueous sol was obtained. This sol was stable at a specific gravity of 1.328, pH of 10.65, and a concentration in terms of metal oxide of 29.1% by weight.

Example 2
(C) Step: 2188 g of the amine component-containing antimony pentoxide colloid prepared in B-1-1 was stirred into 5983 g of the aqueous sol obtained in Step (b) of Example 1 (containing 700 g as SnO ₂ ). was added under mixing to the metal oxide was converted to (B-1-1) / SnO ₂ of 0.05 in the weight proportions.
Step (d): The aqueous medium obtained in Step (c) was aged by heating at 95 ° C. for 2 hours.
Subsequently, the obtained aqueous medium was packed in a column packed with a hydroxyl group anion exchange resin. The obtained stannic oxide aqueous sol (dilute liquid) coated with antimony pentoxide colloid was concentrated at room temperature with a filtration device of an ultrafiltration membrane having a fractional molecular weight of 100,000 and coated with high concentration of antimony pentoxide. 3062 g of an aqueous stannic oxide aqueous sol was obtained.
The stannic oxide aqueous sol coated with antimony pentoxide at a high concentration was distilled off by adding 35 liters of methanol little by little under reduced pressure using a rotary evaporator to replace the water in the aqueous sol with methanol. 2390 g of stannic oxide methanol sol coated with antimony oxide colloid was obtained. This sol has a specific gravity of 1.092, pH of 9.3 (equal mixture with water), viscosity of 1.3 c. p. The concentration in terms of metal oxide was 30% by weight, and the particle diameter was 10 to 15 nm as observed with an electron microscope. The sol had a colloidal color, high transparency, and was stable with no abnormalities such as precipitate formation, white turbidity, and thickening after standing at room temperature for 3 months. The refractive index of the dried sol was 1.9.

Example 3
Step (a): ammonium carbonate in 2500 g of alkaline stannic oxide aqueous sol (A-1) having a SnO ₂ concentration of 3.7% by weight or less in particle diameter of 15 nm (containing 92.5 g as SnO ₂ ). 20.8 g of zirconium (2.8 g as ZrO ₂ ) was added and mixed, and stirring was continued for 30 minutes. Further, this mixture was aged at 100 ° C. for 3 hours. The mixed solution was a sol of a stannic oxide-zirconium oxide composite colloid having a ZrO ₂ / SnO ₂ weight ratio of 0.03 and exhibiting a colloidal color and having good transparency, and 2480 g was obtained. The sol had 3.25% by weight SnO _{2, 0.09%} by weight as ZrO _2, was 3.34 wt% as SnO ₂ + ZrO 2.
Step (b): The stannic oxide-zirconium oxide composite sol obtained in step (a) was hydrothermally treated at a treatment temperature of 240 ° C. and a treatment pressure of 3.5 MPa. The specific surface area of the obtained sol was 57 m ² / g.
(C) Step: Amine prepared with B-1-1 in 2480 g of aqueous sol of colloidal particles of stannic oxide-zirconium oxide composite obtained in step (b) (containing 83 g as SnO ₂ + ZrO ₂ ) 244 g of the component-containing antimony pentoxide colloid was added with stirring, and mixed to 0.05 at a weight ratio of (B-1-1) / (SnO ₂ + ZrO ₂ ) converted to the metal oxide.
Step (d): The aqueous medium obtained in Step (c) is heat-aged at 95 ° C. for 2 hours, and then concentrated at room temperature with a filtration device of an ultrafiltration membrane having a fractional molecular weight of 100,000 to obtain a high concentration pentoxide. A colloid of stannic oxide-zirconium oxide composite coated with antimony was obtained.
By distilling off the water of the stannic oxide-zirconium oxide complex colloid coated with the above-mentioned high concentration antimony pentoxide in a rotary evaporator while adding 8 liters of methanol little by little under reduced pressure, water of the aqueous sol was removed. 133 g of methanol sol of stannic oxide-zirconium oxide composite colloid coated with antimony pentoxide colloid substituted with methanol was obtained. This sol has a specific gravity of 1.082, a pH of 8.5 (equal mixture with water), a viscosity of 1.8 c. p. The concentration in terms of metal oxide was 30% by weight, and the particle diameter was 10 to 15 nm as observed with an electron microscope. The sol had a colloidal color, high transparency, and was stable with no abnormalities such as precipitate formation, white turbidity, and thickening after standing at room temperature for 3 months. The refractive index of the dried sol was 1.9.
Example 4
(C) Step: Example 8 (b) in which 876 g of antimony pentoxide-silicon dioxide complex colloidal solution prepared in B-2-1 (containing 25.3 g as Sb ₂ O ₅ + SiO ₂ ) was stirred. A solution obtained by diluting 3077 g of aqueous sol obtained in the step (containing 360 g as SnO ₂ ) with 3000 g of pure water was added with stirring, and converted to the metal oxide (B-2-1) / (SnO ₂ ) It mixed to 0.07 in the weight ratio.
(D): The aqueous medium obtained in step (c) was aged by heating at 95 ° C. for 2 hours.
The obtained stannic oxide aqueous sol (dilute liquid) coated with antimony pentoxide-silicon dioxide complex colloid was concentrated at room temperature with a filtration device of an ultrafiltration membrane having a fractional molecular weight of 100,000. 1900 g of an aqueous stannic oxide aqueous sol coated with an antimony pentoxide-silicon dioxide complex colloid was obtained. The aqueous stannic oxide aqueous sol coated with the high-concentration antimony pentoxide-silicon dioxide composite colloid was distilled off with water using a rotary evaporator while adding 22 liters of methanol little by little under a slightly reduced pressure. 1180 g of stannic oxide methanol sol coated with antimony pentoxide-silicon dioxide complex colloid in which water in the sol was replaced with methanol was obtained. This sol has a specific gravity of 1.090, a pH of 8.2 (equal mixture with water), a viscosity of 1.6 c. p. The concentration in terms of metal oxide was 30% by weight, and the particle diameter was 10 to 15 nm as observed with an electron microscope. The sol had a colloidal color, high transparency, and was stable with no abnormalities such as precipitate formation, white turbidity, and thickening after standing at room temperature for 3 months. The refractive index of the dried sol was 1.9.
Example 5
(C) Step: 1957 g of a tungsten oxide-stannic oxide-silicon dioxide composite colloid aqueous solution prepared in B-3-1 (containing 45.0 g as WO ₃ + SnO ₂ + SiO ₂ ) was stirred or (Example 1) b) 2564 g of aqueous sol obtained in the step (containing 300 g as SnO ₂ ) was added under stirring, and the weight ratio of (B-3-1) / (SnO ₂ ) converted to the metal oxide. Mixed to 0.15.
(D): The aqueous medium obtained in step (c) was aged by heating at 95 ° C. for 2 hours.
The obtained stannic oxide aqueous sol (dilute liquid) coated with the tungsten oxide-stannic oxide-silicon dioxide composite colloid was concentrated at room temperature by a filtration device of an ultrafiltration membrane having a fractional molecular weight of 100,000, 1327 g of an aqueous stannic oxide sol coated with a high concentration tungsten oxide-stannic oxide-silicon dioxide composite colloid was obtained. Water is distilled off while adding 27 liters of methanol little by little to a rotary evaporator using a rotary evaporator and the aqueous stannic oxide sol coated with the high concentration tungsten oxide-stannic oxide-silicon dioxide composite colloid. As a result, 1080 g of stannic oxide methanol sol coated with a tungsten oxide-stannic oxide-silicon dioxide composite colloid in which water in the aqueous sol was replaced with methanol was obtained. This sol has a specific gravity of 1.130, pH of 7.3 (equal mixture with water), viscosity of 3.9 c. p. The concentration in terms of metal oxide was 31% by weight, and the particle size by electron microscope observation was 10 to 15 nm. The sol had a colloidal color, high transparency, and was stable with no abnormalities such as precipitate formation, white turbidity, and thickening after standing at room temperature for 3 months. The refractive index of the dried sol was 1.9.

(Discoloration test)
The high-temperature and high-pressure treated stannic oxide aqueous sol obtained in the step (b) of Example 1 and the stannic oxide aqueous sol obtained in (A-1) had a SnO ₂ concentration of 4% by weight. To 30% by weight. Each of these concentrated sols was sealed in 15 ml in a 20 ml container. This container was irradiated with ultraviolet rays with a mercury lamp for 20 minutes. Then, the bleedability of these sols was compared.

  The sol obtained in the step (b) of Example 1 exhibited a light blue color when irradiated with ultraviolet rays, but then faded by standing and returned to the original pale yellowish white color.

  The sol obtained in (A-1) became yellowish in color due to ultraviolet irradiation, and did not return to the original pale yellowish white color even after being allowed to stand.

  The high temperature and high pressure treated stannic oxide sol obtained in the step (b) of Example 1 has a crystallinity because it is hydrothermally treated at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. high. Thereby, the specific surface area of the stannic oxide particles becomes smaller than that of the stannic oxide sol (A-1). Although stannic oxide is susceptible to discoloration due to the redox action of ultraviolet rays, the specific surface area of stannic oxide particles that have been subjected to high-temperature and high-pressure treatment is small, so that the ratio has decreased and the above evaluation results were obtained. it is conceivable that.

Claims (6)

The following (a1) step, (b1) step, (c1) step and (d1) step:
(A1) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight,
(B1) step: a step of hydrothermally treating the stannic oxide aqueous sol obtained in the step (a1) for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.,
Step (c1): A molar ratio of stannic oxide aqueous sol obtained in Step (b1) to M / Sb ₂ O ₅ of 0.02 to 4.00 (where M represents an amine molecule) and 1 A step of mixing an alkylamine-containing Sb ₂ O ₅ aqueous sol having a particle diameter of ˜20 nm with a weight ratio of Sb ₂ O ₅ / SnO ₂ converted to the metal oxide to 0.01 to 0.50, and Step (d1): A method for producing a stable sol of modified stannic oxide colloidal particles, comprising a step of aging the aqueous medium obtained in Step (c1) at 20 to 300 ° C. for 0.1 to 50 hours. The following (a2) step, (b2) step, (c2) step and (d2) step:
Step (a2): a stannic oxide aqueous sol having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50 wt%, and an oxyzirconium concentration of 0.1 to 50 wt% in terms of ZrO ₂ An aqueous salt solution was mixed in a weight ratio of 0.001 to 0.50 as ZrO ₂ / SnO ₂ , and the resulting mixture was heated at 60 to 100 ° C. for 0.1 to 50 hours to give 4 to 4 Preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 50 nm;
(B2) Step: The stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a2) is subjected to water for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. A step of performing a heat treatment,
Step (c2): Molar ratio of stannic oxide-zirconium oxide composite aqueous sol obtained in step (b2) and M2 / Sb ₂ O ₅ of 0.02 to 4.00 (where M is an amine molecule) And an alkylamine-containing Sb ₂ O ₅ aqueous sol having a particle diameter of 1 to 20 nm in a weight ratio of Sb ₂ O ₅ / (SnO ₂ + ZrO ₂ ) in terms of the metal oxide is 0.01 to Modified stannic oxide-oxidation comprising the steps of mixing to 0.50 and (d2) step: aging the aqueous medium obtained in step (c2) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of zirconium composite colloidal particles. The following (a3) step, (b3) step, (c3) step and (d3) step:
(A3) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight;
(B3) step: a step of subjecting the aqueous stannic oxide sol obtained in the above step (a3) to hydrothermal treatment for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.,
Step (c3): stannic oxide aqueous sol obtained in step (b3) above, antimony pentoxide having a SiO ₂ / Sb ₂ O ₅ molar ratio of 0.55 to 55 and a particle size of 5 nm or less; An aqueous sol containing composite colloidal particles of silicon dioxide is mixed to 0.01 to 0.50 in a weight ratio of (Sb ₂ O ₅ + SiO ₂ ) / (SnO ₂ ) converted to the metal oxide. Step (d3): A method for producing a stable sol of modified stannic oxide colloidal particles, comprising aging the aqueous medium obtained in Step (c3) at 20 to 300 ° C. for 0.1 to 50 hours . The following (a4) step, (b4) step, (c4) step and (d4) step:
Step (a4): a stannic oxide aqueous sol having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50 wt%, and an oxyzirconium concentration of 0.1 to 50 wt% in terms of ZrO ₂ An aqueous salt solution was mixed in a weight ratio of 0.001 to 0.50 as ZrO ₂ / SnO ₂ , and the resulting mixture was heated at 60 to 100 ° C. for 0.1 to 50 hours to give 4 to 4 Preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 50 nm;
Step (b4): Hydrothermal treatment of the stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a4) at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours. The process of performing,
Step (c4): The stannic oxide-zirconium oxide composite aqueous sol obtained in step (b4) has a SiO ₂ / Sb ₂ O ₅ molar ratio of 0.55 to 55 and a particle size of 5 nm or less. An aqueous sol containing composite colloidal particles of antimony pentoxide and silicon dioxide is converted into its metal oxide in a weight ratio of (Sb ₂ O ₅ + SiO ₂ ) / (SnO ₂ + ZrO ₂ ) of 0.01 to Modified stannic oxide-oxidation comprising the steps of mixing to 0.50 and (d4) step: aging the aqueous medium obtained in step (c4) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of zirconium composite colloidal particles. The following (a5) step, (b5) step, (c5) step and (d5) step:
(A5) Step: Adjusting a stannic oxide aqueous sol containing colloidal particles of stannic oxide having a particle diameter of 4 to 50 nm as SnO _{2 at} a concentration of 1 to 50% by weight;
(B5) step: a step of subjecting the stannic oxide aqueous sol obtained in the step (a5) to a hydrothermal treatment for 0.01 to 100 hours at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C.,
Step (c5): The aqueous stannic oxide sol obtained in Step (b5), a WO ₃ / SnO ₂ weight ratio of 0.1 to 100 having a particle diameter of 2 to 7 nm and 0.1 to 100 An aqueous sol containing a composite colloidal particle of tungsten oxide-stannic oxide-silicon dioxide having a SiO ₂ / SnO ₂ weight ratio was converted into its metal oxide (SnO ₂ + WO ₃ + SiO ₂ ) / (SnO ₂ ) mixing at a weight ratio of 0.01 to 0.50, and (d5) step: aging the aqueous medium obtained in step (c5) at 20 to 300 ° C. for 0.1 to 50 hours A method for producing a stable sol of modified stannic oxide colloidal particles. The following (a6) step, (b6) step, (c6) step and (d6) step:
Step (a6): a stannic oxide aqueous sol having a particle diameter of 4 to 50 nm and a SnO ₂ concentration of 0.5 to 50% by weight, and an oxyzirconium concentration of 0.1 to 50% by weight in terms of ZrO ₂ An aqueous salt solution was mixed in a weight ratio of 0.001 to 0.50 as ZrO ₂ / SnO ₂ , and the resulting mixture was heated at 60 to 100 ° C. for 0.1 to 50 hours to give 4 to 4 Preparing an aqueous sol of a stannic oxide-zirconium oxide composite colloid having a particle size of 50 nm;
Step (b6): Hydrothermal treatment of the stannic oxide-zirconium oxide composite aqueous sol obtained in the step (a6) at a pressure of 0.1 to 40 MPa and a temperature of 100 to 350 ° C. for 0.01 to 100 hours. The process of performing,
Step (c6): A stannic oxide-zirconium oxide composite aqueous sol obtained in step (b6), a WO ₃ / SnO ₂ weight ratio of 0 to 100 having a particle diameter of 2 to 7 nm and 0 An aqueous sol containing tungsten oxide-stannic oxide-silicon dioxide composite colloidal particles having a SiO ₂ / SnO ₂ weight ratio of 1 to 100 was converted to its metal oxide (SnO ₂ + WO ₃ + SiO ₂ ) / (SnO ₂ + ZrO ₂ ) in a weight ratio of 0.01 to 0.50, and (d6) step: the aqueous medium obtained in step (c6) is 0.1 at 20 to 300 ° C. A method for producing a stable sol of modified stannic oxide-zirconium oxide composite colloidal particles, comprising a step of aging for -50 hours.