JP2000204355A - Composite particles, its production, abrasive material and its aqueous dispersion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain composite particles that comprises polymer particles and at least one selected from a metal bonding part to be formed in the polymer particles and silica particles, have sufficient strength and hardness with excellent heat resistance and are useful in cosmetics, electronic materials, magnetic materials, coating materials and the like. SOLUTION: The objective composite particles comprises polymer particles, metal compound parts that directly or indirectly bond to the polymer particles (for example, containing at least one metalloxane bond parts and metal oxide particles and titanium is excluded as a metal constituting the metalloxane bond-containing parts) and silica particles. The composite particles are useful as paint, spacer, optical material, catalyst, photocatalyst, filler, lubricant for electronic film material, diagnostic, medicine, electrically conductive material, sensor material, toner, resin modifier, ink, adsorbing agent, anti-ultraviolet material, masking material and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a composite particle and a method for producing the same, an abrasive containing the composite particle, and an aqueous dispersion containing the composite particle and water. The composite particles of the present invention have sufficient strength and hardness, are excellent in heat resistance, and are suitable for cosmetics, electronic materials, magnetic materials, coating materials, paints, spacers, optical materials, catalysts, photocatalysts, fillers, and electronic material films. Can be used as lubricants, diagnostic agents, pharmaceuticals, conductive materials, sensor materials, toners, resin modifiers, inks, adsorbents, UV-resistant materials, concealing materials, etc., and polishing of abrasives for magnetic disks As a material or the like, it can be used particularly in the form of an aqueous dispersion.

[0002]

2. Description of the Related Art Conventionally, polymer particles having a narrow particle size distribution obtained by copolymerizing a vinyl monomer or the like have been used in applications such as standard particles, carrier particles for diagnostic agents, and lubricants. However, the strength and heat resistance of the polymer particles are not always sufficient, and when used as standard particles or lubricants, when excessive shear stress is applied or the particles are exposed to high temperatures, the particles may be deformed or collapsed. Yes, its use is limited. In order to cope with these problems, there have been proposed particles made of a highly crosslinked copolymer obtained by copolymerizing a crosslinkable vinyl monomer or the like. But,
Particles composed of such a crosslinked polymer have low hardness and insufficient heat resistance as compared with inorganic particles, and therefore cannot be used in a wide range of applications.

[0003] In applications such as electronic materials, magnetic materials, heat-resistant materials, and polishing materials, particles composed of a large number of metal compounds are used, and various composite particles have been proposed to diversify applications. . As such composite particles,
By coating the iron oxide particles with a silicon compound, when manufacturing a needle-shaped magnetic material by heat treatment, its shape, composite particles that prevent sintering between the magnetic materials, etc., the strength for powder metallurgy Composite particles in which iron powder used as a large material is coated with copper, and composite particles in which iron oxide particles are coated with antimony oxide and aluminum oxide to improve the heat resistance, and the like are given. However, each of these composite particles is made of a metal compound and has too high a hardness, so that it cannot always sufficiently cope with diversification of uses. Therefore, development of composite particles having appropriate hardness is particularly required in the fields of electronic materials, magnetic materials, optical materials, polishing materials, and the like.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. By providing a metal compound portion and the like inside and on the surface of polymer particles, sufficient strength,
Has hardness, excellent heat resistance, and moderately flexible,
An object of the present invention is to provide a composite particle that can be used in a wide range of applications as described above and a method for producing the composite particle. Further, the present invention includes an abrasive containing the composite particles, and the composite particles and water, an electronic material, a magnetic material, an optical material, and the like, a water-based dispersion useful in various applications, particularly, a magnetic disk and the like. An object of the present invention is to provide an aqueous dispersion used for polishing.

[0005]

Means for Solving the Problems The composite particles of the first invention are:
A polymer particle, and a metal compound portion (at least one of a metalloxane bond-containing portion and a metal oxide particle portion formed directly or indirectly on the polymer particle, constituting the metalloxane bond-containing portion; And at least one of a silica particle part).

[0006] The method for producing composite particles according to the fifth invention is characterized in that:
A part of the linking compound is chemically bonded to the polymer particles, and then (1) the above is chemically bonded or chemically bonded and polycondensed with the other part of the linking compound.
And (2) at least one of a metal compound part and a silica particle part is indirectly formed on the polymer particles by at least one of the above chemical bonding.

Further, a method for producing composite particles according to a seventh aspect of the present invention comprises:
Without using the linking compound used in the fifth invention, in the presence of the polymer particles, (1) the above is chemically bonded or chemically bonded and polycondensed, and (2) the above is chemically bonded. Wherein at least one of the metal particles and the silica particles is directly formed on the polymer particles by at least one of the above.

The above-mentioned "polymer particles" are particles comprising a polymer obtained by polymerizing various monomers. Examples of the monomer include unsaturated aromatic compounds such as styrene, α-methylstyrene, halogenated styrene and divinylbenzene, unsaturated esters such as vinyl acetate and vinyl propionate, and unsaturated nitriles such as acrylonitrile. Can be used. Also, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, 2-ethylhexyl acrylate,
2-ethylhexyl methacrylate, lauryl acrylate, lauryl methacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate,
Glycidyl acrylate, glycidyl methacrylate,
Acrylic esters such as 2-hydroxyethyl acrylate, acrylic acrylate and allyl methacrylate or methacrylic esters can also be used.

Further, butadiene, isoprene, acrylic acid, methacrylic acid, acrylamide, methacrylamide, N-methylolacrylamide, N-methylolmethacrylamide and the like can also be used. These monomers may be used alone or in combination of two or more. Further, a functional group such as a hydroxyl group, an epoxy group, and a carboxyl group can be introduced into the polymer particles. When a functional group is introduced into the polymer particles as described above,
The metal compound portion or the silica particle portion can be formed directly on the polymer particles without the need for a linking compound such as a silane coupling agent. However, in particular, when a silane coupling agent having a functional group capable of reacting with the introduced functional group is used in combination, the bonding between the metal compound portion or the silica particle portion and the polymer particle is further promoted, and further excellent. High performance composite particles can be obtained.

Polymer particles are obtained by emulsion polymerization of these monomers,
It can be obtained by polymerizing by various methods such as suspension polymerization and dispersion polymerization. According to these polymerization methods, the particle size of the polymer particles can be appropriately adjusted depending on the polymerization conditions and the like. Furthermore, a polymer such as a lump can be pulverized into polymer particles having a required particle size. In particular, when polymer particles having high strength and the like and excellent heat resistance are required, when producing the polymer particles, a polyfunctional monomer is used in combination, and a crosslinked structure is introduced into the molecule. Can be. This crosslinked structure can be introduced by a method such as chemical crosslinking or electron beam crosslinking in the course of producing the polymer particles or after producing the polymer particles.

As the polymer particles, in addition to the above, particles composed of various polymers such as polyamide, polyester, polycarbonate and polyolefin can be used.
In these polymer particles, a functional group can be introduced in the same manner as described above, and further, a crosslinked structure can be introduced in the molecule.

Although the shape of the polymer particles is not particularly limited,
A more spherical shape is preferred. That LASER PA
The average particle size measured by RTICLE ANALYZER PAR-III (manufactured by Otsuka Electronics Co., Ltd.) is 0.02.
To 50 μm, particularly 0.05 to 20 μm.
μm, and more preferably 0.05 to 1.0 μm. If the average particle size is less than 0.02 μm, the particles are likely to aggregate, and if it exceeds 50 μm, the dispersion stability of the aqueous dispersion is poor, which is not preferable.

At least a part of the “metal compound part” and the “silica particle part” is directly or indirectly chemically or non-chemically bonded to the polymer particles. It is particularly preferable that they are "chemically bonded" as in the third invention. As a result, there is no problem that these easily drop off from the polymer particles. The chemical bond includes an ionic bond and a coordinate bond, and a covalent bond is more preferable because the bond is particularly strongly bonded. Also, as a non-chemical bond,
Examples include hydrogen bonding, surface charge bonding, entanglement bonding, and anchor effect bonding.

Further, the above-mentioned "metal oxide particle portion" is a fourth metal oxide particle portion.
As in the invention, it may be constituted by “alumina particle part”, “titania particle part” or “zirconia particle part”, or may be constituted by all of these. Further, the alumina particle part, the titania particle part, the zirconia particle part, and the silica particle part of the first to third aspects of the present invention may be formed inside the polymer particles and on the entire surface thereof, or a part of them. It may be formed. Further, the “metalloxane bond-containing portion” may be composed of a single molecule, but preferably has a chain structure of two or more molecules. In the case of a chain structure, it may be linear, but a two-dimensional or three-dimensional structure is more preferable.

The metalloxane bond-containing part and each particle part are
In addition to being formed as described above, the following configuration can be adopted. (1) All of the metalloxane bond-containing portion and each particle portion may be directly or indirectly chemically or non-chemically bonded to the polymer particles, or at least one of them may be polymer particles. May be combined. (2) Others may be bonded to the metalloxane bond-containing portion bonded to the polymer particles or to an intermediate portion or end portion of each particle portion. (3) A metalloxane bond-containing portion or a metalloxane bond-containing portion or each particle portion which is not bonded to the polymer particle and which is not bonded to the polymer particle is chemically bonded to the polymer particle. It may be captured by a metalloxane bond-containing portion or each particle portion which is bound chemically or non-chemically.

The metal compound part or the silica particle part is the seventh
They may be directly bonded to the polymer particles and formed as in the invention, or may be bonded and formed through a linking compound such as a silane coupling agent as in the fifth invention. Good. In the fifth invention, the above-mentioned "linking compound" is used, which is interposed between the polymer particles and at least one of the foregoing and connects them. As the coupling compound, a coupling agent such as a silane coupling agent, an aluminum-based coupling agent, a titanium-based coupling agent, and a zirconium-based coupling agent can be used. Coupling agents are particularly preferred. As the silane coupling agent, the following (a) and (b)
And (c).

(A) vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane and γ-chloropropyl (B) N-β (aminoethyl) γ, such as (b) γ-glycidoxypropyl trimethoxysilane and γ-glycidoxypropyl methyldiethoxysilane
-Aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane and the like.

These silane coupling agents include:
Those having a functional group in the molecule that can easily react with a functional group such as a hydroxyl group, an epoxy group, or a carboxyl group introduced into the polymer particles are preferable. For example, in the case of polymer particles into which a carboxyl group has been introduced, the silane coupling agents (b) and (c) having an epoxy group and an amino group are preferred. Among them, γ-glycidoxypropyltrimethoxysilane and N-β (aminoethyl) γ-
Aminopropyltrimethoxysilane is particularly preferred.

Further, examples of the aluminum-based coupling agent include acetoalkoxyaluminum diisopropylate, and examples of the titanium-based coupling agent include isopropyltriisostearoyl titanate and isopropyltridecylbenzenesulfonyl titanate. . One of these various coupling agents may be used alone, or two or more thereof may be used in combination. Further, different types of coupling agents can be used in combination.

The amount of the coupling agent interposed between the polymer particles and the above-mentioned compound or colloidal substance is based on 1 mol of the functional group which the polymer particles have or which is introduced into the particles. , Preferably 0.1 to 50 mol. This amount is particularly preferably 0.5 to 30 mol, more preferably 1.0 to 20 mol. If the amount of the coupling agent is less than 0.1 mol, the metal compound portion or each particle portion is not sufficiently firmly bonded to the polymer particles, and is easily dropped from the polymer particles, which is not preferable. If the amount used exceeds 50 mol, the condensation reaction of the coupling agent molecules proceeds, and a new polymer is generated in addition to the reaction with the molecules constituting the polymer particles. Bonding may be hindered. When the coupling agent is chemically bonded to the polymer particles, a catalyst such as an acid and a base may be used to promote the reaction. Further, the reaction can be promoted by raising the temperature of the reaction system.

In the compound represented by the above general formula, R _n M (OR ′) _zn , M is Al, V, Cr, M
n, Fe, Co, Ni, Cu, Zn, Ge, Zr, N
b, Mo, Sn, Sb, Ta, W, Pb or Ce. R in this general formula is a methyl group,
Ethyl group, n-propyl group, iso-propyl group, n-
Examples include an alkyl group such as a butyl group, a sec-butyl group, a tert-butyl group and an n-pentyl group, a phenyl group, a vinyl group, and a monovalent organic group such as a glycidpropyl group. Further, as R ′, a methyl group, an ethyl group,
Examples include alkyl groups such as n-propyl group and iso-propyl group, acyl groups such as acetyl group, propionyl group, butyryl group, valeryl group and caproyl group, and aryl groups such as phenyl group and tolyl group. . When R and R 'are two or more, they may be the same or different.

M is particularly preferably Al and Zr. Hereinafter, the case where M is these elements will be described. Examples of the compound in which M is Al include aluminum ethoxide, and examples of the compound in which M is Zr include zirconium-tert-butoxide. These compounds form a metalloxane bond-containing part and an alumina particle part or a zirconia particle part. These compounds may be used alone or in combination of two or more. M is Al or Z
The compound represented by r can be used in combination. Further, the above (z-n) is 1 or more, preferably 2 or more, more preferably 3 or more, and in this case, a denser metalloxane bond-containing portion is formed.

As these compounds, not only those represented by the above general formula but also at least one of a hydrolyzate and a partial condensate of this compound can be used. The compound of the above-mentioned general formula is a compound which undergoes hydrolysis or partial condensation without any particular operation. If necessary, a compound which has been hydrolyzed or partially condensed at a required ratio may be used.

The amount of these compounds used is 0.02 in weight ratio to polymer particles in terms of Al ₂ O ₃ or ZrO _2.
It is preferably set to 01 to 100. This weight ratio is particularly preferably 0.005 to 50, and more preferably 0.01 to 10. If the weight ratio is less than 0.001, the metal compound part is not sufficiently formed inside and on the surface of the polymer particles. On the other hand, if this weight ratio exceeds 100,
It is not preferable because the hardness of the polymer particles becomes too high.

In the fifth and seventh inventions, the above-mentioned "colloidal alumina", the above-mentioned "colloidal titania", the above-mentioned "colloidal zirconia" and the above-mentioned "colloidal silica" are used in a dispersion medium such as water. Dispersed average particle size 5 to 50
Fine particles of 0 nm alumina, titania, zirconia or silica. These fine particles can be prepared by a method of growing particles in an alkaline aqueous solution, a gas phase method, or the like, and practically used as a colloid in which these are dispersed in a dispersion medium such as water. In addition, colloidal titania and colloidal silica are, like the colloidal alumina and zirconia, the above-mentioned general formula, R _n M
In (OR ′) _zn , M can be formed from a compound in which M is Ti or Si, thereby forming a titania particle portion or a silica particle portion.

These fine particles may constitute alumina particles, titania particles, zirconia particles, or silica particles without binding to the polymer particles. However, in that case, it is necessary to be captured by a metalloxane bond-containing part or the like. Furthermore, the above-mentioned respective particle portions may be formed by bonding to polymer particles or a metalloxane bond-containing portion by a hydroxyl group or the like formed in these fine particles. The amount of colloid used is Al
_In terms of ₂ O ₃ , TiO ₂ , ZrO ₂ or SiO ₂ , the weight ratio is preferably 0.001 to 100 with respect to the polymer particles. This weight ratio is particularly preferably 0.01 to 50, and more preferably 0.1 to 10. If the weight ratio is less than 0.001, each particle portion is not sufficiently formed, which is not preferable. On the other hand, if it exceeds 100, the hardness of the polymer particles becomes too high, which is not preferable.

The binding of various coupling agents to polymer particles and the reaction of the above compounds with various coupling agents such as colloidal alumina, or the direct reaction of polymer particles with water or alcohol, etc. Can be carried out in a dispersion system using various organic solvents as dispersion media. These dispersion media may be used alone, or two or more appropriate dispersion media such as water and alcohol may be used in combination. In the case of a dispersion medium containing water, hydrophilic functional groups such as a hydroxyl group, an epoxy group and a carboxyl group are introduced into the polymer particles in order to stably and uniformly disperse the polymer particles in a dispersion system. It is preferable to keep it. In addition, by introducing these functional groups, various coupling agents or compounds of the above-mentioned compounds and the like to the polymer particles,
It can also be more easily chemically and / or non-chemically bonded.

As the alcohol, it is preferable to use lower saturated aliphatic alcohols such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol and tert-butanol. These alcohols may be used alone or in combination of two or more. Further, as the organic solvent other than the alcohol, methyl ethyl ketone, dimethylformamide and the like can be used, and these organic solvents, water and alcohol can be used together in an appropriate quantitative ratio.

In this reaction, the content of the polymer particles in the dispersion medium is from 0.001 to 70% by weight (hereinafter referred to as
“%” Is% by weight. ), Particularly preferably 0.01 to 50%, more preferably 0.1 to 25%. If the content is less than 0.001%, the yield of the composite particles is small, while if it exceeds 70%, the dispersion stability of the polymer particles is reduced, and a gel is easily generated at the stage of the composite. Therefore, it is not preferable.

Further, the reaction for forming the metal compound portion or the silica particle portion can be promoted by heating or using a catalyst. When heating, the temperature of the reaction system is preferably set to 40 to 100 ° C. Further, as the catalyst, an acid, a base, an aluminum compound, a tin compound and the like can be used. Particularly, an acid catalyst and an aluminum catalyst have a large effect of accelerating the reaction. Furthermore, in this production method, after forming the metal compound portion and the like, dilute the dispersion with water or an alkaline aqueous solution,
It is preferable to remove an organic solvent such as an alcohol using an evaporator or the like as necessary.

The dilution can be performed using water or an alkaline aqueous solution such as an aqueous ammonia solution and an aqueous potassium hydroxide solution. The concentration of this alkaline aqueous solution is 0.0
It is preferably from 0.01 to 10%, particularly preferably from 0.01 to 1%. Note that the dilution operation is preferably performed by dropping the dispersion containing the composite particles into the diluent little by little using a dispenser, a pipette, or the like, but while stirring the dispersion containing the composite particles in water or an alkaline aqueous solution. May be added.

The shape of the "composite particles" is not particularly limited, but is preferably more spherical. The average particle size (equivalent sphere diameter) is preferably 0.03 to 100 μm, particularly 0.05 to 20 μm, and more preferably 0.05 to 100 μm.
It is more preferable that the thickness be 1.0 μm. If the average particle size is less than 0.03 μm, the particle size is too small to obtain required characteristics in various uses such as electronic materials, magnetic materials, optical materials, and polishing materials. If the ratio exceeds, the storage stability of an aqueous dispersion or the like containing the composite particles is notably reduced. The average particle size of the composite particles can be measured by the same device as that for the polymer particles.

The composite particles can be used as an abrasive as in the eighth invention. The abrasive may contain only the composite particles, or may be an abrasive in which an acid, an alkali, an oxidizing agent, a surfactant and the like are further blended.

Further, as in the ninth invention, it can be used in various applications as an aqueous dispersion containing composite particles and water. If necessary, the aqueous dispersion may be added with an acid and an oxidizing agent. The required components can be blended and used as an abrasive for a magnetic disk or the like as in the tenth invention. The content of the composite particles in the aqueous dispersion is 0.001 to 70%.
It is preferred that This content is particularly 0.01 to
More preferably, it is set to 50%, further preferably 0.1 to 20%. When the content of the composite particles is less than 0.001%, required performance cannot be obtained in applications such as electronic materials, magnetic materials, optical materials, and polishing materials. It is not preferable because the storage stability of the contained aqueous dispersion is significantly reduced. The medium of the aqueous dispersion may be only water, or an organic solvent such as alcohol,
A mixed medium can be used in combination as long as the polymer particles are not dissolved.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described more specifically with reference to embodiments. (1) Preparation of Aqueous Dispersion of Polymer Particles Synthesis Example 1 (Preparation Example of Aqueous Dispersion of Divinylbenzene Polymer Particles) In a 7-liter four-necked flask, add 3 parts of ion-exchanged water.
353 g and a 15% aqueous solution of an anionic surfactant (manufactured by Sanyo Chemical Industry Co., Ltd., trade name: “MON-7”).
4 g was added and the mixture was stirred for 10 minutes. Thereafter, 343 g of a 32% aqueous dispersion of a spherical styrene polymer (average particle size: 0.15 μm) was added, and the mixture was stirred for 5 minutes while blowing nitrogen gas. Next, the flask was immersed in a water bath, and when the temperature reached 80 ° C., 110 g of a 2% aqueous solution of sodium persulfate was added.

Then, the ion-exchanged water 3 was added to the flask.
44 g, 147 g of a 15% aqueous solution of MON-7, nonionic surfactant (trade name “E920” manufactured by Kao Corporation)
35 g of a 25% aqueous solution of
g was previously mixed and continuously charged over 3 hours. Next, the contents of the flask were reacted at 80 ° C. for 2 hours, and then 55 g of methacrylic acid, 550 g of ion-exchanged water,
And 55 g of a 1% aqueous solution of sodium persulfate were further added.
The reaction was carried out for 2 hours while maintaining the temperature at 0 ° C. afterwards,
Cool to room temperature, remove aggregates by filter,
An aqueous dispersion of divinylbenzene polymer particles was obtained. The solid content concentration of this aqueous dispersion was 19.8%. The average particle size of the polymer particles was 0.33 μm.

Synthesis Example 2 (Another Preparation Example of Aqueous Dispersion of Divinylbenzene Polymer Particles) In place of methacrylic acid in Synthesis Example 1, acrylic acid 5
An aqueous dispersion of divinylbenzene polymer particles was obtained in the same manner as in Synthesis Example 1 except that 5 g was used. The solid content concentration of this aqueous dispersion was 19.7%. The average particle size of the polymer particles was 0.31 μm.

Synthesis Example 3 (Preparation Example of Aqueous Dispersion of Styrene-Methacrylic Acid Copolymer Particles)
078 g of a 1% aqueous solution of an anionic surfactant (trade name “Emal AD-25R”, manufactured by Kao Corporation)
g, 119 g of styrene and 21 g of methacrylic acid, and the mixture was stirred for 5 minutes while purging with nitrogen gas. Thereafter, the flask was immersed in a water bath, and when the temperature reached 75 ° C., 140 g of a 5% aqueous solution of ammonium persulfate was added.

Next, after reacting at a temperature of 75 ° C. for 1 hour, a mixture of 1232 g of styrene and 28 g of methacrylic acid was continuously charged into the flask over a period of 4 hours, and reacted at 75 ° C. for 3 hours. After cooling down to room temperature,
An aqueous dispersion of styrene-methacrylic acid copolymer particles was obtained. The solid concentration of this aqueous dispersion was 20%. The average particle size of the polymer particles was 0.19 μm.

(2) Production of Aqueous Dispersion Containing Composite Particles Example 1 (Example of Production of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 1) Divinylbenzene Obtained in Synthesis Example 1 The aqueous dispersion of the polymer particles was heated and concentrated until the solid content of the aqueous dispersion became 40%. After cooling, 2-propanol was added to dilute the solid content to 15%, followed by stirring for 10 minutes. A water / 2-propanol mixed dispersion of polymer particles was prepared. Thereafter, 533 g of this water / 2-propanol mixed dispersion was put into a two-liter three-necked flask, immersed in a water bath adjusted to 60 ° C., and stirred. Subsequently, 11 g of a silane coupling agent, γ-glycidoxypropyltrimethoxysilane (hereinafter abbreviated as “GPTS”), was continuously added over 2 hours, and reacted at 60 ° C. for 3 hours. Cooled to room temperature.

Then, 200 g of aluminum ethoxide
Was added continuously over 2 hours and reacted for 2 hours. Next, 1000 g of ion-exchanged water was charged and stirred for 1 hour. Further, 50 g of a 1% aqueous solution of potassium hydroxide was added, stirring was continued for 1 hour, and then cooled to room temperature. afterwards,
2-propanol was removed to obtain an aqueous dispersion of composite particles having a solid content of 12%. The average particle size of the composite particles was 0.42 μm.

Example 2 (Another Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 1) Except that the aqueous potassium hydroxide solution in Example 1 was changed to 10% aqueous ammonia. In the same manner as in Example 1, an aqueous dispersion of composite particles having a solid content of 11% was obtained. The average particle size of the composite particles was 0.42 μm.

Example 3 (Another Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 1) Solid Content of Aqueous Dispersion of Divinylbenzene Polymer Particles Obtained in Synthesis Example 1 Was heated and concentrated until the solid content became 40%, and after cooling, 2-propanol was added to dilute the solid content to 24%, followed by stirring for 10 minutes to obtain water / 2-propanol of divinylbenzene polymer particles. A mixed dispersion was prepared. Then, 170 g of the water / 2-propanol mixed dispersion was placed in a 300 ml three-necked flask.
Immerse in a water bath adjusted to 60 ° C,
Stirred. Next, 10 g of GPTS was continuously added over 2 hours, reacted at 60 ° C. for 3 hours, and then cooled to room temperature.

Thereafter, a water / 2-propanol mixed dispersion of the GPTS-bound polymer particles (solid content: 22
%) Into another flask having a capacity of 300 ml, and 39 g of 2-propanol was added thereto.
It was immersed in a water bath adjusted to 5 ° C. and stirred.
Next, 79 g of aluminum ethoxide was continuously added over 2 hours and reacted for 2 hours. After completion of the reaction, the mixture was cooled, and 150 g of the reaction solution was continuously dropped into 3 liters of a 0.01% aqueous solution of potassium hydroxide. Thereafter, 2-propanol was removed, and the composite particles having a solid content concentration of 8% were removed. An aqueous dispersion was obtained. The average particle size of the composite particles is 0.42.
μm.

Example 4 (Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 2) The solid content of the aqueous dispersion of divinylbenzene polymer particles obtained in Synthesis Example 2 was 37. %, And after cooling, add 2-propanol and dilute to a solid content of 15%, and then stir for 10 minutes to mix and disperse divinylbenzene polymer particles in water / 2-propanol. The body was prepared.

Next, the water / 2-propanol mixed dispersion of divinylbenzene polymer particles obtained in Synthesis Example 1 in Example 1 was replaced with the above water / 2-propanol mixed dispersion, and a silane coupling agent was used. GPTS to N-β
An aqueous dispersion of composite particles having a solid content of 12% was obtained in the same manner as in Example 1 except that 9 g of (aminoethyl) γ-aminopropyltrimethoxysilane was used. Also,
The average particle size of the composite particles was 0.48 μm.

Example 5 (Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 3) Solid of aqueous dispersion of styrene-methacrylic acid copolymer particles obtained in Synthesis Example 3 The mixture was heated and concentrated until the solid content reached 36%, and after cooling, 2-propanol was added to reduce the solid content to 15%.
%, And then stirred for 10 minutes to prepare a water / 2-propanol mixed dispersion of styrene-methacrylic acid copolymer particles.

Next, the water / 2-propanol mixed dispersion of the divinylbenzene polymer particles obtained in Synthesis Example 1 in Example 1 was replaced with the above water / 2-propanol mixed dispersion, and 10 g of GPTS and 10 g of aluminum were used. 100 g of ethoxide and 10% aqueous solution of potassium hydroxide
In the same manner as in Example 1 except that 5 g of aqueous ammonia was used, an aqueous dispersion of composite particles having a solid content of 10% was obtained. The average particle size of the composite particles was 0.25 μm.

Example 6 (Another Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 3) Aqueous dispersion of styrene-methacrylic acid copolymer particles obtained in Synthesis Example 3 The mixture was heated and concentrated until the solid content of the mixture became 40%, and after cooling, 2-propanol was added to reduce the solid content to 15%.
%, And then stirred for 10 minutes to prepare a water / 2-propanol mixed dispersion of styrene-methacrylic acid copolymer particles.

Next, 533 g of this water / 2-propanol mixed dispersion was put into a two-liter three-necked flask, immersed in a water bath adjusted to 60 ° C., and stirred. Thereafter, 11 g of GPTS was continuously added over 2 hours, and reacted at 60 ° C. for 3 hours. Next, 100 g of aluminum ethoxide and 120 g of a 30% 2-propanol dispersion of fumed silica were continuously added to the flask over a period of 2 hours, and reacted for 2 hours. Thereafter, 50 g of a 1% aqueous solution of potassium hydroxide was added, and stirring was continued for 1 hour. Then, 1000 g of ion-exchanged water was added, and the mixture was cooled to room temperature. Next, 2-propanol was removed to obtain an aqueous dispersion of composite particles having a solid content of 9%. The average particle size of the composite particles was 0.24 μm.

Example 7 (Another Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 3) Aqueous dispersion of divinylbenzene polymer particles of Synthesis Example 1 used in Example 1 Was replaced with the aqueous dispersion of styrene-methacrylic acid copolymer particles of Synthesis Example 3 and the solid content concentration was 10% in the same manner as in Example 1 except that aluminum ethoxide was replaced with aluminum propoxide. An aqueous dispersion of the composite particles was obtained. The average particle size of the composite particles is 0.1.
It was 21 μm.

Example 8 (Another Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 3) The styrene obtained in Synthesis Example 3 was placed in a three-necked flask having a capacity of 2 liters. 421 g of an aqueous dispersion of methacrylic acid copolymer particles (solid content: 20%) was charged, immersed in a water bath adjusted to 60 ° C., and stirred. After that, GPTS
10 g was continuously added over 2 hours and reacted at 60 ° C. for 3 hours. Next, zirconium-t was added to the flask.
After continuously adding 15 g of tert-butoxide over 2 hours and continuing stirring for 1 hour, 1000 g of ion-exchanged water was added.
It was charged and cooled to room temperature. Thereafter, 2-propanol was removed to obtain an aqueous dispersion of composite particles having a solid content of 10%. The average particle size of the composite particles is 0.22μ.
m.

Example 9 (Other Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 3) Aqueous dispersion of styrene-methacrylic acid copolymer particles obtained in Synthesis Example 3 The mixture was heated and concentrated until the solid content became 39%, and after cooling, 2-propanol was added to add a solid content of 15%.
%, And then stirred for 10 minutes to prepare a water / 2-propanol mixed dispersion of styrene-methacrylic acid copolymer particles.

Next, the water / 2-propanol mixed dispersion of divinylbenzene polymer particles obtained in Synthesis Example 1 in Example 1 was replaced with the above-mentioned water / 2-propanol mixed dispersion, and the addition of GPTS was omitted. Other than that, an aqueous dispersion of composite particles having a solid content of 9% was obtained in the same manner as in Example 1. The average particle size of the composite particles is 0.2
It was 3 μm.

Example 10 (Other Production Example of Aqueous Dispersion of Composite Particles Obtained Using Polymer Particles of Synthesis Example 3) The procedure of Example 8 was repeated except that the addition of GPTS was omitted.
An aqueous dispersion of composite particles having a solid content of 10% was obtained. The average particle size of the composite particles was 0.21 μm.

(3) Example of Application to Polishing Composition for Magnetic Disk Substrate Diluting with water so that the concentration of the composite particles contained in the aqueous dispersions obtained in Examples 1, 6 and 8 is 5% by weight. Then, aluminum nitrate was added as a polishing accelerator to this diluent to a concentration of 5% to obtain a polishing agent. Also,
For comparison, colloidal silica (manufactured by Nissan Chemical Co., Ltd.
Product name “Snowtex 20”), fumed silica (Nippon Aerosil Co., Ltd., product name “Aerosil # 9”)
0 ") was prepared in the same composition except that each contained 5%.

The magnetic disk substrate was polished using the above-mentioned abrasive under the following conditions, and the polishing rate and the presence or absence of polishing scratches were evaluated. <Polishing conditions> Substrate: 3.5 inch aluminum disk with Ni-P electroless plating (one-step polished) Polishing device: Lappmaster SFT Co., Ltd., model "L"
M-15C "polishing pad: Rodel (USA) Inc., trade name" Polytex DG "processing pressure: 70 g / cm ² Platen rotational speed: 50 rpm Polishing agent supply rate: 15 ml / min Polishing time: 10 min

<Evaluation method> Polishing rate: From the weight loss of the disk due to polishing, the following formula was used.
Therefore, the polishing rate was determined. Polishing rate (nm / min) = [(W / d) / S] × 10⁷  W: Weight reduction by polishing per minute, d: No Ni-P
Density of electrolytic plating, S; area to be polished Abrasive scratch: After polishing and drying the polished disk, the dark room
Spotlight inside and visually check for polishing scratches
did. The evaluation criteria are as follows. ◎: no polishing scratches observed, ○: slight polishing scratches observed
×, multiple polishing scratches of a problematic size were observed
You. Table 1 shows the evaluation results.

[0059]

[Table 1]

According to the results in Table 1, when the aqueous dispersion of the present invention was used as an abrasive and a magnetic disk was polished,
It can be seen that the polishing rate is high and polishing scratches do not occur.
On the other hand, when colloidal silica or fumed silica was used, a large number of polishing scratches were observed, although the polishing rate was slightly lower.

[0061]

According to the first to fourth inventions, composite particles having sufficient strength and hardness, excellent heat resistance, and useful in various applications such as electronic materials, magnetic materials, optical materials, and polishing materials. Can be obtained. Further, according to the fifth to seventh inventions, the specific composite particles of the first to fourth inventions can be easily produced. In particular, according to the seventh invention, specific composite particles can be similarly produced without using a linking compound. Further, according to the eighth invention, an abrasive containing the composite particles can be obtained, and according to the ninth invention, an aqueous dispersion useful in various uses such as electronic materials, magnetic materials, and optical materials can be obtained. This aqueous dispersion is particularly useful as an abrasive for magnetic disks and the like as in the tenth invention.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C09C 1/28 C09C 1/28 3/10 3/10 (72) Inventor Akira Iio Tsukiji, Chuo-ku, Tokyo 11-11-24 JSR Co., Ltd. F-term (reference) 3C058 AA07 CA01 CB01 DA02 4G076 AA02 AA18 AA26 BA14 BB08 BC02 BD02 CA26 DA01 DA02 DA07 DA16 DA25 DA30 4J037 AA08 AA18 AA22 AA25 AA30 CB05 EE23 CB05 EE02

Claims (10)

[Claims] 1. A polymer particle and a metal compound part (at least one of a metalloxane bond-containing part and a metal oxide particle part formed directly or indirectly on the polymer particle, And at least one of a silica particle portion and a composite particle. 2. The method according to claim 1, wherein at least a part of the metal compound part and the silica particle part are chemically bonded to another part of the linking compound whose part is chemically bonded to the polymer particles. Composite particles. 3. The composite particles according to claim 1, wherein at least a part of the metal compound part and the silica particle part are directly chemically bonded to the polymer particles. 4. The composite according to claim 1, wherein the metal oxide particles are composed of at least one of alumina particles, titania particles, and zirconia particles. particle. 5. A method of chemically bonding a part of the linking compound to the polymer particles, and then (1) chemically bonding or chemically bonding the following to the other part of the linking compound and performing polycondensation; and 2) A method for producing composite particles, wherein at least one of a metal compound part and a silica particle part is indirectly formed in the polymer particles by at least one of the following chemical bonding: General formula, R _n M (OR ′) _zn (R is 1 having 1 to 8 carbon atoms)
A valent organic group, R ′ is an alkyl group having 1 to 5 carbon atoms, an acyl group having 2 to 6 carbon atoms or an aryl group having 6 to 9 carbon atoms, and M is Al, V, Cr, Mn, Fe, Co , Ni, C
u, Zn, Ge, Zr, Nb, Mo, Sn, Sb, T
a, W, Pb or Ce, wherein z is the valency of M; n is an integer of 0 to (z-1), and when n is 2 or more, Rs may be the same or different. When (z−n) is 2 or more, R ′ may be the same or different. ). At least one of colloidal alumina, colloidal titania, colloidal zirconia, and colloidal silica. 6. The method according to claim 5, wherein the linking compound is a silane coupling agent. 7. In the presence of a polymer particle, the polymer particle
(1) chemically bonding or chemically bonding and polycondensing the following; and (2) chemically bonding the following to directly form a metal compound portion and a silica particle portion on the polymer particles. A method for producing composite particles, wherein at least one of them is formed. General formula, R _n M (OR ′) _zn (R is 1 having 1 to 8 carbon atoms)
A valent organic group, R ′ is an alkyl group having 1 to 5 carbon atoms, an acyl group having 2 to 6 carbon atoms or an aryl group having 6 to 9 carbon atoms, and M is Al, V, Cr, Mn, Fe, Co , Ni, C
u, Zn, Ge, Zr, Nb, Mo, Sn, Sb, T
a, W, Pb or Ce, wherein z is the valency of M; n is an integer of 0 to (z-1), and when n is 2 or more, Rs may be the same or different. When (z−n) is 2 or more, R ′ may be the same or different. ). At least one of colloidal alumina, colloidal titania, colloidal zirconia, and colloidal silica. 8. The composite particle according to any one of claims 1 to 4, or the composite particle according to any one of claims 5 to 7.
An abrasive containing the composite particles produced by the method described in the above item. 9. The composite particle according to any one of claims 1 to 4, or the composite particle according to any one of claims 5 to 7.
13. An aqueous dispersion containing the composite particles produced by the method described in the item 6 and water. 10. The aqueous dispersion according to claim 9, which is used for an abrasive.