JPH06200040A - Colored composite particle - Google Patents

Abstract

(57) [Summary] [Purpose] It has excellent strength and heat resistance, has a narrow particle size distribution and a sufficient degree of coloring, does not elute or migrate to the liquid crystal component of the coloring component, and is also excellent in adhesion. In particular, it provides colored composite particles suitable as colored spacer particles in a liquid crystal display. [Structure] Coloring in which an organic polymer coating layer is formed on the surface of a colored substrate particle in which a coloring metal compound coating layer is provided on fine particles by a hydrolysis reaction of a hydrolyzable metal salt and / or metal alkoxide Composite particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored composite particle, and more particularly to a colored composite particle suitable as a colored spacer particle for keeping an appropriate thickness of a liquid crystal layer in a liquid crystal display.

[0002]

2. Description of the Related Art Conventionally, a liquid crystal display (hereinafter referred to as "LC
"D". ), Spacer particles (hereinafter referred to as LC particles) are used to regulate the substrate gap and to keep the thickness of the liquid crystal layer appropriate.
The spacer particles for D are simply referred to as "spacer particles". ) Is used. Generally, such spacer particles have sufficient strength and heat resistance to withstand the pressure and heating conditions in the LCD substrate assembly process, have a narrow particle size distribution capable of uniformly maintaining the substrate gap, and have a liquid crystal component. It does not dissolve and contains few impurities such as metal ions (preferably 10 ppm per particle)
Below), it is required not to disturb the alignment of the liquid crystal. In addition, more recently, especially from the viewpoint of improving the image quality by improving the contrast of the color liquid crystal panel,
Colored spacer particles (hereinafter, the colored spacer particles for LCD are simply referred to as “colored spacer particles”) have come to be used, but it is strongly demanded that these colored spacer particles have sufficient light shielding properties. In addition, spacer particles including colored spacer particles have excellent adhesiveness, and it is necessary that the spacer particles do not move during a liquid crystal panel manufacturing process such as liquid crystal injection or during use of the liquid crystal panel. The conventional colored spacer particles are (a) a method of dyeing uncolored spacer particles, and (b) a monomer containing a colorant is subjected to suspension polymerization or emulsion polymerization to obtain colored particles, and then classified. Method, (C)
It is produced by a method in which a polymer and a colorant are kneaded and then granulated and classified, and (d) a method of coating the surface of polymer particles with a pigment. However, among the conventional colored spacer particles, those obtained by the method of (a) above, in general, the dye does not sufficiently penetrate into the inside of the particle, the color tone is thin, and the light-shielding property is not sufficient. May elute or migrate into the liquid crystal component to disturb the alignment of the liquid crystal, and in the case of those obtained by the above methods (b) and (c), the substrate particles have no affinity with the constituent component. Or, since a poor colorant is dispersed at a high concentration, the particles often become brittle, and in the case of the product obtained by the method (d) above, the pigment on the particle surface is easily peeled off or dropped, and the colorant causes Therefore, there is a problem that the impurity concentration cannot be sufficiently lowered, and it is extremely difficult to obtain colored particles satisfying the above conditions 1 to 3 by the conventional method.

[0003]

Therefore, the present invention is excellent in strength and heat resistance, has a narrow particle size distribution and a sufficient degree of coloring, and does not elute or migrate a coloring component into a liquid crystal component.
Moreover, it is an object of the present invention to provide colored composite particles which are excellent in adhesiveness and the like and which are particularly suitable as colored spacer particles.

[0004]

The present invention provides a colored metal compound coating layer to be a shell on fine particles to be a core by a hydrolysis reaction of a hydrolyzable metal salt and / or a metal alkoxide in a solution, It comprises colored composite particles in which an organic high polymer coating layer is formed on the surface of colored substrate particles obtained by subjecting to heat treatment as required.

The present invention will be described in detail below. This will clarify the objects, configurations and effects of the present invention. First, the fine particles (hereinafter,
It is called "core particles". ), For example, glass, silica, aluminum, titanium, iron, nickel,
Inorganic materials such as copper, silver, gold, stainless steel, iron oxide, ferrite, carbon black: (co) polymers of olefins such as ethylene and propylene; (co) polymers of aromatic vinyl compounds such as styrene and divinylbenzene ;
(Co) polymer of vinyl ester such as vinyl acetate; (co) polymer of vinyl cyanide compound such as acrylonitrile;
(Co) polymer of (meth) acrylic acid ester such as methyl methacrylate; (co) polymer of halogenated vinyl compound such as vinyl chloride and tetrafluoroethylene; polyacetal; polycarbonate; polyester; alkyd resin; unsaturated polyester; Polyarylate; Polysulfide; Polysulfone; Polyamide; Polyimide; Polysiloxane; Epoxy resin; Phenolic resin; Urea resin;
Organic materials such as melamine resins; benzoguanamine resins; cellulose; starch; ionomers can be used. When the core fine particles are an organic material, they may have a crosslinked structure. These core fine particles may be particles obtained by kneading and mixing two or more kinds of materials in advance and then granulating and classifying the particles, or may be a mixture of two or more kinds of particles made of different materials. The color tone of these core fine particles is not particularly limited, and may be white or colored, and may be transparent or opaque.

Particularly in terms of the colored spacer particles,
The pressure and heating conditions in the LCD substrate assembly process differ depending on the type of LCD, but the compression resistance (ie strength) of the base particles in the colored spacer particles is usually 30 Kgf / mm ² or more per particle, preferably Has a breaking strength of 50 Kgf / mm ² or more, and the particles do not break under the pressure condition after the spacer particles are sprayed. Also, regarding the heat resistance (that is, the thermal decomposition temperature) of the base particles, , 100 ° C or higher, preferably 15
It is desirable that the temperature is 0 ° C. or higher.
It is desirable that the CD substrate is compressed and deformed to a certain extent by heating under pressure in the assembly process. Therefore, as the core fine particles, silica particles and particles made of an organic polymer material having a crosslinked structure are preferable.

The method for preparing the core fine particles is not particularly limited, but for example, rolling granulation, fluidized bed granulation, stirring granulation, crushing / crushing granulation, compression granulation, extrusion granulation. ,
Physical granulation methods such as melt granulation, mixed granulation, spray cooling granulation, spray drying granulation, precipitation / precipitation granulation, freeze drying granulation, suspension coagulation granulation, and drop cooling granulation; emulsion polymerization, A chemical granulation method such as suspension polymerization or precipitation polymerization may be appropriately selected according to the material of the core fine particles, granulated, and classified.
In addition, when the core fine particles are commercially available, they can be used.

The average particle size of the core fine particles and the standard deviation of the particle size distribution are appropriately set depending on the desired characteristics of the obtained colored composite particles, the intended use, etc. The average particle size of the core fine particles is
It is preferably 0.05 to 50 μm, more preferably 2 to
The standard deviation of the particle size distribution is preferably ± 10% or less of the average particle size, more preferably ± 5% or less, and particularly preferably ± 3% or less. Particularly, in order to obtain colored composite particles suitable as colored spacer particles, it is preferable that the standard deviation of the particle size distribution of the core fine particles is small.

The core fine particles may be a hollow body or an internal porous body as long as they are not easily crushed or deformed in the manufacturing process of colored composite particles or the LCD substrate assembly process described later.

In the present invention, a uniform colored metal compound coating layer serving as a shell is provided on the above core fine particles. Here, coloring means having a color tone other than colorless or white.

The treatment for forming the colored metal compound coating layer on the core fine particles is a hydrolyzable metal salt (hereinafter, simply referred to as "metal salt") and / or in the solution state in the presence of the core fine particles. Alternatively, a metal alkoxide (hereinafter, the metal salt and the metal alkoxide are collectively referred to as “hydrolyzable metal salt or the like”) is hydrolyzed, and heat treatment is performed if necessary. As a result, a uniform coating layer composed of a colored metal compound such as a metal hydroxide or a metal oxide formed by hydrolysis or a heat treatment applied as necessary is formed on the core fine particles, and the core / shell structure is formed. Will have.

Here, as the metal salt, for example, FeCl ₃ ,
FeCl ₂ , CrCl ₃ , TiCl ₄ , ZrCl ₄ , YCl ₃ , AlCl ₃ , CuCl
Chlorides such as ₂ ; Fe (NO ₃ ) ₃ , Cr (NO ₃ ) ₃ , Ti (NO ₃ ) ₄ , Zr (N
_{O 3) 4, Y (NO} 3) 3, Al (NO 3) 3, Cu (NO 3) ₂ such as a nitrate; Fe
₂ (SO ₄ ) ₃ , FeSO ₄ , Ti (S0 ₄ ) ₂ , Zr (SO ₄ ) ₂ , Y ₂ (SO ₄ ) ₃ , Al
₂ (SO ₄ ) ₃ , CuSO _{4 and} other sulfates can be mentioned, and examples of the metal alkoxide include Ti (OC ₂ H ₅ ) ₄ and Ti.
Titanium alkoxides such as (OC ₃ H ₇ ) ₄ and Ti (OC ₄ H ₉ ) ₄ ; Zr (OC ₂
Examples thereof include zirconium alkoxides such as H ₅ ) ₄ , Zr (OC ₃ H ₇ ) ₄ and Zr (OC ₄ H ₉ ) ₄ . These metal salts and metal alkoxides may be used alone or in admixture of two or more, and the metal salt and metal alkoxide may be used in combination.

The above-mentioned hydrolyzable metal salt and the like are dissolved in a solution state at room temperature or by heating,
Easily hydrolyzed, for example Fe (OH) ₃ , α-Fe ₂ O ₃ ,
γ-Fe ₂ O ₃ , Fe ₃ O ₄ , Cr (OH) ₃ , Cr ₂ O ₃ , Cr ₃ O ₄ , Cr
O ₂ , Ti (OH) ₄ , TiO ₂ , TiO ₂ , Zr (OH) ₄ , ZrO ₂ , Y (OH) ₃ ,
Y ₂ O ₃ , Al (OH) ₃ , Al ₂ O ₃ , Cu (OH) ₂ , Cu ₂ O, CuO, Cu (O
H) ₂ CuCO ₃ and other metal hydroxides, metal oxides, etc. are produced, and these metal compounds form a uniform coating layer on the surface of the core fine particles. When the coating layer is composed of a metal hydroxide, it can be easily converted into a metal oxide by heat treatment at an appropriate temperature, for example, 50 to 400 ° C. Further, the metal oxide layer on the core fine particles is placed in a hydrogen atmosphere at an appropriate temperature, for example, 100 to 800.
It is also possible to convert to a partially reduced metal oxide layer by applying a heat treatment at ℃. At that time, when the generated metal hydroxide is colored, it is converted to the metal oxide as it is, or when the generated metal hydroxide is white, by converting to the metal oxide, A colored metal compound coating layer is formed on the core fine particles.

In the present invention, the color tone of the colored metal compound that coats the colored substrate particles is preferably black or blackish brown. Therefore, as the metal compound, Fe is used.
₃ O ₄ , Cr ₂ O ₃ , Cr ₃ O ₄ , TiO 2, CuO and the like are preferable.

The concentration of the hydrolyzable metal salt or the like in the hydrolysis reaction is preferably 0.01 mmol / solvent 1 liter or more, more preferably 0.1 mmol / solvent 1 liter or more, particularly preferably 1 Mmol /
The solvent is 1 liter or more. The upper limit concentration of the hydrolyzable metal salt or the like is a concentration at which the compound can be completely dissolved in the reaction solvent at room temperature or under heating, and a uniform hydrolysis reaction can be generated. Although it varies depending on the kind, it is usually 1000 mmol / liter of solvent or less.

The concentration of the core fine particles in the hydrolysis reaction is preferably 0.001 g / solvent 1 liter or more, more preferably 0.01 g / solvent 1
It is liter or more, particularly preferably 0.5 g / solvent 1 liter or more. The upper limit concentration of the core fine particles is a concentration capable of maintaining a uniform dispersion state of the core fine particles and the obtained colored substrate particles, and is usually 1000 g / solvent 1 liter or less.

The reaction solvent in the hydrolysis reaction is
Water; alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, t-butanol and the like can be used, and water and / or saturated alcohols are particularly preferable. When water and alcohol are used in combination, the amount of alcohol used is appropriately adjusted in consideration of miscibility with water, solubility of hydrolyzable metal salt and the like in a mixed solvent, and the like.

In the hydrolysis reaction, it is important to maintain a uniform dispersion state of the core fine particles and the obtained colored substrate particles in the solution of the hydrolyzable metal salt or the like. For example, when the dispersion state of the core fine particles is poor and the core fine particles are aggregated into several to several hundreds, the aggregate is directly coated with the colored metal compound,
Uniform colored substrate particles cannot be obtained, and even when the obtained colored substrate particles are associated or aggregated in the reaction mixture and cannot be redispersed, uniform colored substrate particles cannot be obtained.

In order to maintain the uniformly dispersed state of the core fine particles and the colored substrate particles, a polymer compound soluble in a solution of a hydrolyzable metal salt, a surfactant or the like is used as a dispersion improving agent to react. It is preferably added to the mixed solution.

Examples of such dispersion improvers include high molecular compounds such as sodium salt of carboxymethyl cellulose, hydroxyethyl cellulose, sodium polyacrylate, poloethylene oxide, polyvinyl alcohol, polyvinylpyrrolidone; sodium stearate,
Surfactants such as sodium polycarboxylate, sodium dodecylbenzene sulfonate, sodium lauryl sulfate, sodium diphenyl ether disulfonate, and sodium succinate dialkyl ester sulfonate can be mentioned. Preferred dispersion improvers are polyvinylpyrrolidone, sodium dodecylbenzene sulfonate and the like. These dispersion improvers can be used alone or in admixture of two or more with respect to the polymer compound and the surfactant, respectively, and the polymer compound and the surfactant can be used in combination.

The amount of these dispersion improvers used is preferably 1 part by weight or more, more preferably 3 to 300 parts by weight, particularly preferably 5 to 100 parts by weight of the core fine particles.
It is 250 parts by weight.

In the present invention, there are basically two mechanisms for forming the colored metal compound coating layer on the core fine particles. One of them is a mechanism in which a hydrolyzed metal ion and / or a complex produced by hydrolysis is adsorbed on the surface of core fine particles to form a coating layer.
The other one is that, through a hydrolysis step, nuclei composed of extremely small metal compound fine particles are initially formed, and the fine nuclei particles are adsorbed on the surface of the core fine particles by a hetero-aggregation mechanism to grow a coating layer. Is the mechanism. In the latter mechanism, the thickness of the coating layer can be controlled by adjusting the number and particle size of the metal compound particles adsorbed on the core particles.

Of the above two mechanisms, the mechanism that goes through the hetero-aggregation mechanism becomes dominant when the core fine particles have an electric charge. For example, when the hydrolysis reaction of a hydrolyzable metal salt or the like occurs at a pH equal to or higher than the isoelectric point of the produced metal compound fine particles, the core fine particles have a positive charge, so that the metal compound fine particles are efficiently adsorbed. .
Further, when the hydrolysis reaction of the hydrolyzable metal salt or the like occurs at a pH below the isoelectric point of the metal compound fine particles, the core fine particles have a negative charge, so that the metal compound fine particles are efficiently adsorbed. become.

Therefore, in order to increase the charge difference between the metal compound fine particles and the core fine particles when the core fine particles are generated, and to improve the coating efficiency of the core fine particles with the metal compound,
The pH may be adjusted by adding an acid or an alkali, or urea and / or formamide may be added to the reaction mixture and heated to adjust the pH by thermal decomposition thereof.

When the core fine particles are an organic material,
By introducing a functional group having a positive or negative charge on the surface of the core fine particles, the metal compound fine particles can be more efficiently adsorbed on the surface of the core fine particles. Specific examples of such a functional group include a sulfonic acid group, an amino group, a phosphoric acid group, a carboxyl group, an epoxy group, an azo group, and the like, and these functional groups can be easily prepared by a conventionally known method. Can be introduced on the surface of the core fine particles. Further, regardless of whether the core fine particles are an inorganic material or an organic material, the core fine particles of the metal compound fine particles are obtained by previously adsorbing the surfactant and / or the surface active polymer having the functional group on the surface of the core fine particles. Adsorption to the surface can be promoted. Regarding these surfactants and / or surface active polymers, refer to the section of the third method for forming the organic polymer coating layer on the surface of the colored substrate particles described later.

The manufacturing process of the colored base material particles as described above is a highly advantageous process from the industrial viewpoint, since the production efficiency of the colored base material particles is high and it is safe.

The average particle size of the colored substrate particles thus obtained
(R ₁ ) is usually set to 0.1 to 50 μm. In particular, the preferable average particle size (R ₁ ) of the colored spacer particles as the colored substrate particles is 2 to ₁₀ μm. The colored substrate particles obtained are usually spherical or nearly spherical, but the particle size when the colored substrate particles are not necessarily symmetrical is assumed to be the minor axis diameter. When the average particle diameter (R ₁ ) of the colored base particles is less than 0.1 μm, the core fine particles are necessarily 0.1 μm.
Smaller, the particles are too small, the resulting colored composite particles may be a mixture of large-sized particles in which small-sized particles or some small-sized particles are complexed, and uniform colored composite particles may not be obtained. On the other hand, the average particle diameter (R ₁ ) of the colored substrate particles is 5
If it exceeds 0 μm, the core fine particles also inevitably have a large diameter, and when the colored metal compound coating layer is provided on the core fine particles, a gap or an excessively thin portion may occur in the coating layer, resulting in an insufficient coloring degree. There is.

The standard deviation of the particle size distribution of the colored substrate particles is preferably set to ± 10% or less of the average particle size, more preferably ± 5% or less, and particularly preferably ± 3% or less. In particular, in order to keep the thickness of the liquid crystal layer as the colored spacer particles constant, the smaller the standard deviation is, the more preferable.

The ratio of the core fine particle diameter to the outer diameter of the colored base material particles having a core / shell structure in the present invention is usually 0.4 to 0.99, preferably 0.6 to 0.99. In order to make the ratio of the core fine particle diameter to the outer diameter of the coloring base material particle less than 0.4, the ratio of the average thickness of the colored metal compound coating layer to the outer diameter of the coloring base material particle is 0.3 or more, that is,
It is necessary to make the ratio of the average thickness of the colored metal compound coating layer to the core fine particle diameter 3/4 or more, but it is difficult to form such a thick coating layer on fine core fine particles. If the ratio of the diameter of the core fine particles to the outer diameter of the colored substrate particles is larger than 0.99, the colored metal compound coating layer may be too thin and the degree of coloring may be insufficient.

The colored substrate particles thus obtained are
After the hydrolysis reaction, it may or may not be separated once.
However, in the subsequent treatment for producing the colored composite particles, there are a dry system and a wet system as described later, but in the latter case, when the reaction solvent used for the hydrolysis reaction can be used as it is, It goes without saying that it is more efficient as a method for producing colored composite particles that the colored substrate particles are not separated.

Next, a method for forming an organic polymer coating layer on the surface of the colored substrate particles will be described. As a method of forming the organic high-molecular-weight polymer coating layer, for example, there are three methods which will be sequentially described below. The first method is to mix the colored substrate particles and the organic high-molecular polymer particles in a state in which the crushing and melting of the colored substrate particles do not substantially occur,
By applying at least a compressive force and a shearing force to each of the particles, the organic polymer particles are adhered to the surface of the colored substrate particles. In this case, the organic polymer particles have an average particle size (R ₂ ) of 0.003 to
1 μm, the particle size ratio (R ₂ / R ₁ ) to the average particle size (R ₁ ) of the colored substrate particles is 1/10 or less, and the standard deviation of the particle size distribution is ± 40% or less of the average particle size. preferable.

In the first method, the organic polymer particles to be adhered to the surface of the colored base particles are preferably those which can smooth the surface of the colored composite particles by the mixing treatment described later. Therefore, the organic polymer particles are composed of a thermoplastic polymer and have a glass transition temperature of, for example, 25 to 200 ° C., preferably 90 to 1
It is 80 ° C. In particular, since the fused organic high-molecular polymer particles have thermoplasticity, the organic high-molecular polymer particle layer existing on the surface of the colored composite particles adheres to the LCD substrate in the LCD substrate assembly step, so that the colored spacer is formed. The movement of particles can be effectively suppressed.

Examples of materials for such organic polymer particles include (co) polymers of olefins such as ethylene and propylene; (co) polymers of aromatic vinyl compounds such as styrene and α-methylstyrene; (Co) polymers of vinyl esters such as vinyl acetate and vinyl propionate; (co) polymers of (meth) acrylates such as methyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; (meth) (Co) polymers of vinyl cyanide compounds such as acrylonitrile and vinylidene cyanide; vinyl chloride,
(Co) polymers of vinyl halide compounds such as vinylidene chloride; polyacetals; polycarbonates; polyesters; polysulfides; polysulfones; polyamides; polysiloxanes; ionomers. These organic polymer particles may be particles obtained by kneading two or more kinds of materials in advance and then granulating, or may be a mixture of two or more kinds of particles made of different materials.

The average particle size (R ₂ ) of the organic polymer particles is
0.003 to 1 μm, preferably 0.1 to 0.5 μm, and the particle size ratio between the organic polymer particles and the colored substrate particles.
(R ₂ / R ₁ ) is preferably 1/10 or less. At this time, when the organic high-molecular polymer particles have an asymmetrical shape such as an ellipse, the particle diameter has a minor axis diameter. When the average particle size (R ₂ ) of the organic polymer particles is less than 0.003 μm,
The particles are likely to agglomerate and may not be uniformly attached to the surface of the base material particles, and when it exceeds 1 μm, the particle size ratio (R ₂ / R ₁ ) of the particles to the colored base material particles is 1 / If it is 10 or less, the average particle diameter (R ₁ ) of the colored base particles also exceeds 10 μm, but in such a case, each particle is too large as a whole to obtain uniform colored composite particles. Can be difficult.

The standard deviation of the particle size distribution of the organic polymer particles is usually ± 40% or less of the average particle size, preferably ± 10% or less. The smaller this standard deviation is, the more uniformly the particles can be attached to the surface of the colored substrate particles, but the standard deviation is not limited as much as the case of the colored substrate particles. This is because even if the particle size distribution is somewhat wide, the organic polymer particles are fused and integrated with each other by the compressive force and the shearing force acting in the mixing process described later, and the surface of the obtained colored composite particles is considerably This is because the colored composite particles can be made smooth and uniform.

The shape of the organic high molecular weight polymer particles is preferably spherical, but like the standard deviation of the particle size distribution, it is not limited as much as the colored substrate particles, and the organic high molecular weight polymer particles are hollow. It can be a body or a porous body.

The method for preparing the organic polymer particles as described above is not particularly limited, and the above-mentioned physical granulation method, chemical granulation method, etc. are appropriately selected for granulation. After that, classify. In addition, when the organic polymer particles are commercially available, they can be used.

When the colored composite particles are produced by the first method, the colored base particles and the organic polymer particles are mixed under the condition that the crushing and melting of the colored base particles do not substantially occur. By applying at least a compressive force and a shearing force to each particle, the organic polymer particles are adhered to the surface of the colored base particle. In this case, an impact force and / or a twisting friction force can be further applied. In the first method, it is preferable to apply a twisting frictional force in addition to the compressing force and the shearing force.

In the first method, the mixing is performed in a state in which the crushing and melting of the colored base material particles do not substantially occur, so that the colored base material particles have substantially the same original shape and size during the mixing process. Therefore, the colored composite particles having a uniform particle size can be produced. However, in the first method, it is usually unnecessary to consider melting or softening of the colored metal compound coating layer, and when only the thin layer portion of the colored metal compound coating layer is crushed, or when the colored substrate particles are Although the constituent core fine particles are slightly softened, it is considered that crushing and melting are not substantially caused even when the colored base material particles can substantially retain their original shape and size during the mixing process.

The "compressive force" in the first method means the radial direction of each particle which acts when the colored substrate particles and the organic polymer particles are pressed against each other or the walls of the mixing container, the stirring blades and the like. It means the force that is the main component. The "shearing force" means a force for shearing the particle layer existing in the mixing space, and is, for example, a force generated in the vicinity of the stirring blade of the stirrer or in the region where the speed difference between the particles is large. Further, the "impact force" means a force that strongly acts in a short time when the particles collide with each other or with a mixing vessel wall, a stirring blade, etc., and "twisting friction force" means, for example, two particles. Means a twisting force (torsion force) accompanied by friction that acts on the molten organic high-molecular polymer particle layer existing in the roll gap by the roll rotation speed difference and the roll pressure.

The forces such as the compressive force and the shearing force are basically the forces that act even when kneading a general polymer material, but in the usual kneading operation for a polymer material, the polymer is finally mixed. While the entire material is melted and plasticized, the first
It should be noted that in the method of (1), the colored substrate particles do not substantially crush or melt during the whole mixing process.

The mixing method in the first method is not particularly limited as long as it can exert at least a compressive force and a shearing force on the colored substrate particles and the organic polymer particles. As such a mixing method,
For example, a method using a mortar; a method using a rotary container type solid mixer such as an inclined cylinder type tumbler, a V type tumbler, and a double cone type tumbler; a mechanical stirring type solid mixer such as a ribbon type mixer and a rotary disk type mixer. Method using complex type solid mixer such as V-type tumbler with internal blade, double-cone tumbler with internal blade; kneader such as kneader mixer, internal mixer, Mueller mixer, Henschel mixer, roll mill The method includes a method using a mechanical stirrer such as a turbine type stirrer and a bull margin type stirrer; and an impact force by a high-speed air flow or a method using mechanical stirrer. In the first method, an impact force by a high-speed air flow or a mixing method using it and mechanical stirring is particularly suitable, and an example of an apparatus therefor is a hybridizer manufactured by Nara Machinery Co., Ltd., Hosokawa Micron Corporation. The Ong mill etc. which were manufactured can be mentioned.

In these mixing methods, whether the compressive force and the shearing force, or the impact force and / or the twisting frictional force which act depending on the case mainly act on the stirring speed and the mixing system (stirring blade, roll, Although various mixing conditions such as air flow etc. are complicatedly related and cannot be generally stated, the compressive force and the shearing force are forces acting in the above-mentioned mixing method in general. On the other hand, the impact force works effectively when using, for example, a high-speed stirrer or a high-speed air flow, and the twist friction force works effectively, for example, when mixing between two rolls or by a meshing screw.

The mixing of the colored substrate particles and the organic polymer particles in the first method is usually dry mixing,
In some cases, the mixed system may be slightly moistened with water, an organic liquid, a plasticizer, or the like. Upon mixing, the colored base material particles and the organic high molecular weight polymer particles may be charged into the mixer at the same time, and either the colored base material particles or the organic high molecular weight polymer particles may be charged first, and the remaining The particles may be added all at once or continuously or stepwise.

In the first method, it is preferable that the mixed system is placed under insulation so that each particle can be easily charged. By placing the mixed system under insulation, the particles of different materials usually have different charge species, and as a result of being attracted to each other, adsorption of the organic polymer particles to the coloring base material particles is promoted, While the organic polymer particles adhere firmly to the surface of the colored substrate particles, the same particles do not repel each other and aggregate.

Room temperature is usually sufficient as the mixing temperature in the first method, but heating or cooling may be carried out as necessary. These are appropriately selected according to the glass transition temperature of the organic polymer particles.

The weight ratio of the colored base material particles to the organic high molecular weight polymer particles in the first method varies depending on the average particle size, properties, etc. of the particles to be combined, but per 100 parts by weight of the colored base material particles, The organic polymer particles are usually 10 to 2
It is 00 parts by weight.

The mixing time in the first method varies depending on the mixing temperature, the stirring speed, the mixing conditions such as the mixing method, the properties of each particle and the like.
It is preferable to mix for about 120 minutes, and in other mixing methods, it is sufficient that the mixing time is shorter than that in the case of using a mortar, but it is necessary to appropriately adjust the mixing time. Further, the administration power at the time of mixing cannot be unconditionally defined depending on the mixing conditions, the properties of each particle, etc., but a suitable mixing time and administration power can be selected by experiments.

By mixing the particles as described above, the contact point between the particles or the contact point between the particles and the wall of the mixing vessel, the stirring blade, etc. is temporarily reduced to, for example, 1
A high heat of around 000 ° C. is instantaneously generated, and the organic high-molecular polymer particles are melted and integrated, and firmly adhered and bonded to the surface of the colored base material particles to further coat the colored metal compound coating layer. become.

The second method for forming the organic polymer coating layer on the surface of the colored substrate particles is the silane coupling agent having a polymerizable unsaturated bond (hereinafter referred to as "unsaturated"). A monomer having a polymerizable unsaturated bond (hereinafter referred to as “polymerizable monomer”) is treated in the dispersion liquid of the colored substrate particles after the treatment with a “silane coupling agent”). Preferably, it is heated in the presence of a polymerization catalyst, if necessary, to perform graft copolymerization.

Examples of the unsaturated silane coupling agent include vinyltrichlorosilane, methylvinyldichlorosilane, dimethylvinylchlorosilane, ethylvinyldichlorosilane, diethylvinylchlorosilane, divinyldichlorosilane, vinyltris (β-methoxyethoxy) silane and vinyl. Trimethoxysilane, vinylmethoxydiethoxysilane, vinyldimethoxyethoxysilane, vinyltriethoxysilane, vinyltrimethylsilane, vinylmethyldiethylsilane, vinyldimethylethylsilane, vinyltriethylsilane, vinyltriacetoxysilane, γ-methacryloxypropyltrimethoxy Silane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyldimethylmethoxysilane, γ-methacryloyl Xypropyltrimethylsilane, γ-methacryloxypropyltriethoxysilane,
γ-methacryloxypropylmethyldiethoxysilane,
γ-methacryloxypropyl dimethylethoxysilane,
Allyltrichlorosilane, allyldimethylchlorosilane, allyltrimethoxysilane, allyltriethoxysilane and the like can be mentioned.

When the surface of the colored substrate particles is treated with the unsaturated silane coupling agent, the colored substrate particles are dispersed in a suitable dispersion medium to form a slurry, and the unsaturated silane coupling agent is stirred. Is added, for example, room temperature to 100 ° C
Then, the reaction is performed for about 1 to 120 minutes.

In this case, the amount of the unsaturated silane coupling agent used is usually 100 parts by weight of the colored base particles.
0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight,
It is particularly preferably 0.5 to 5 parts by weight. If the amount of the unsaturated silane coupling agent used is less than 0.01 part by weight, it will be difficult to effectively graft-copolymerize the polymerizable monomer on the surface of the colored substrate particles, and most of the resulting polymers will be colored groups. There is a possibility that it will be present separately from the material particles, and even if it exceeds 10 parts by weight, the graft copolymerization rate on the surface of the colored substrate particles does not particularly improve, and it is inefficient.

The amount of the dispersion medium used is usually 0.1 to 1000 parts by weight, preferably 0.5 to 100 parts by weight, based on 1 part by weight of the colored base particles.

The dispersion medium used in the treatment with the unsaturated silane coupling agent is water depending on the type of the colored base particles, the unsaturated silane coupling agent, or the polymerizable monomer or the polymerization catalyst described later. And / or it is appropriately selected from hydrophilic or hydrophobic organic solvents and used alone or in combination of two or more kinds. Here, examples of the hydrophilic organic solvent include methanol, ethanol and acetone, and examples of the hydrophobic organic solvent include benzene, toluene and hexane.

In the treatment with the unsaturated silane coupling agent, a dispersion improver may be added to the dispersion medium, if necessary, in order to improve the dispersibility of the colored substrate particles. Examples of such dispersion improvers include those used at the time of producing colored base particles.

The dispersion of the colored substrate particles treated with the unsaturated silane coupling agent can be used as it is for the polymerization of the polymerizable monomer in the next step, and if desired, the treated colored group can be used. The material particles may be separated from the dispersion medium and then redispersed in another dispersion medium.

The polymerizable monomer is polymerized in the dispersion liquid of the colored substrate particles treated with the unsaturated silane coupling agent in this manner to convert the polymerizable monomer into the unsaturated silane coupling agent. Is graft-copolymerized on the surface of the colored base material particles through the unsaturated bond to form an organic polymer coating layer on the surface of the colored base material particles.

In the graft copolymerization, after separating the colored substrate particles treated with the unsaturated silane coupling agent from the dispersion medium, the dispersion medium to be redispersed is the colored substrate particles, the unsaturated silane coupling agent, the polymerizable Depending on the type of monomer, polymerization catalyst, etc., water and / or the same hydrophilic or hydrophobic organic solvent as described above may be appropriately selected and used alone or in combination of two or more.

In the graft copolymerization, the order of addition of the treated colored substrate particles, the polymerizable monomer, the polymerization catalyst and the like can be appropriately selected. It is preferable to add a monomer and a polymerization catalyst. In this case, the polymerizable monomer and the polymerization catalyst may be added at the same time, or one of the polymerizable monomer and the polymerization catalyst may be added and then the other may be added.

In the graft copolymerization, a dispersion improver may be added to the dispersion medium, if necessary, in order to improve the dispersibility of the treated colored base particles and the obtained colored composite particles. As such a dispersion improver,
Mention may be made of those used when producing colored substrate particles. Further, as a matter of course, the dispersion liquid containing the dispersion improving agent added in the step of treating the colored substrate particles with the unsaturated silane coupling agent can be used as it is at the time of graft copolymerization.

Examples of the polymerizable monomer include (meth) acrylic acid, α-chloroacrylic acid, crotonic acid,
Unsaturated carboxylic acids such as maleic acid, maleic anhydride, fumaric acid; vinyl halide compounds such as vinyl chloride, vinylidene chloride, vinyl fluoride, tetrafluoroethylene; styrene, α-methylstyrene, vinyltoluene, vinylpyridine, Aromatic vinyl compounds such as divinylbenzene and diisopropenylbenzene; vinyl acetate,
Vinyl esters such as vinyl propionate, vinyl butyrate, vinyl stearate, vinyl benzoate; methyl (meth) acrylate, ethyl (meth) acrylate, (meth)
2-hydroxyethyl acrylate, propyl (meth) acrylate, butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth)
Lauryl acrylate, stearyl (meth) acrylate,
Benzyl (meth) acrylate, mono- or di (meth) acrylate of (poly) ethylene glycol, (poly)
Unsaturated carboxylic acid esters such as mono- or di (meth) acrylate of propylene glycol, mono- or di (meth) acrylate of 1,4-butanediol, mono-, di- or tri (meth) acrylate of trimethylolpropane; 3-butadiene, isoprene, 1,
3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-butadiene, chloroprene, 2,3-
Dienes such as dichloro-1,3-butadiene; (meth)
Acrylamide, N-methyl (meth) acrylamide,
N-ethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N-methylol (meth) acrylamide, N-2-hydroxyethyl (meth) acrylamide, N, N '-Methylenebis (meth) acrylamide,
Unsaturated amides such as N, N'-ethylenebis (meth) acrylamide; unsaturated nitriles such as (meth) acrylonitrile, α-chloroacrylonitrile, α-chloromethylacrylonitrile, α-methoxyacrylonitrile, vinylidene cyanide; methyl Vinyl ether, divinyl ether, ethylene glycol divinyl ether,
1,4-vinyloxybutane, (meth) allyl vinyl ether, methyl methacryl ether, dimethacryl ether, ethylene glycol dimethacryl ether, 1,4
-Unsaturated ethers such as methacryloxybutane and di (meth) allyl ether; vinyldimethylamine, vinyldiethylamine, N-vinylpyrrolidone, N-vinylcarbazole, divinylamine, dimethacrylamine, di (meth) allylamine, etc. A nitrogen-containing unsaturated compound of
Other sulfur-containing unsaturated compounds such as methyl vinyl sulfide, divinyl sulfide, dimethacryl sulfide, di (meth) allyl sulfide, methyl vinyl sulfone, divinyl sulfone, dimethacryl sulfone and di (meth) allyl sulfone can be mentioned. These polymerizable monomers may be used alone or in admixture of two or more.

The amount of the polymerizable monomer used varies depending on the desired film thickness of the organic polymer coating layer, but is usually 0.5 to 1000 parts by weight per 100 parts by weight of the colored substrate particles.
It is preferably 1 to 100 parts by weight.

As the polymerization catalyst used in the graft copolymerization, for example, sulfur dioxide, an aqueous solution of sulfurous acid, sodium bisulfite, a compound such as sodium bisulfite, which produces sulfite ion and / or bisulfite ion;
Redox type polymerization catalysts containing persulfates such as potassium persulfate, sodium persulfate and ammonium persulfate; benzoyl peroxide, lauroyl peroxide, di-t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, paramenthane hydroperoxide, 2,2'-azobisisobutyronitrile, 2,
Radical polymerization catalysts such as 2'-azobisisovaleronitrile and 2,2'-azobis (2-aminopropane) dihydrochloride are mentioned. These polymerization catalysts may be used alone or
A mixture of two or more species can be used.

The amount of the polymerization catalyst used is 100
It is usually 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, per part by weight.

The polymerization conditions in the graft copolymerization vary depending on the type of the polymerizable monomer, the polymerization catalyst, the dispersion medium, etc., but the polymerization temperature is usually about 0 to 100 ° C., the polymerization time is usually 10 Minutes to 48 hours.

In the second method, depending on the case,
The graft copolymerization of the polymerizable monomer can also be carried out by irradiating with light in the presence or absence of the polymerization catalyst. In the photopolymerization, a sensitizer such as aromatic ketones such as benzophenone and Michler's ketone; acetophenones such as acetophenone and benzoin ether; diketones such as benzyl; acyloxime esters; acylphosphine oxides are usually used. To do.

The organic polymer coating layer formed by such graft copolymerization is uniform, and the bond with the colored substrate particles is strong.

Further, the third method for forming the organic polymer coating layer on the surface of the colored substrate particles is the colored substrate particles, the surfactant and / or the surface active polymer, and the polymerizable monomer. Is preferably polymerized by heating, if necessary, in the presence of a polymerization catalyst. Here, the surface-active polymer means a polymer having a hydrophilic portion and a hydrophobic portion in the polymer molecule and soluble in the dispersion liquid of the colored substrate particles. In this method, the order of addition of the colored substrate particles, the surfactant and / or the surface active polymer, the polymerizable monomer, the polymerization catalyst and the like can be appropriately selected. It is preferable to add an agent and / or a surface-active polymer to form a molecular layer of the surface-active agent and / or the surface-active polymer on the surface of the colored substrate particles, and to form the molecular layer preferentially. Then, it is preferable to add a surfactant and / or a surface active polymer prior to the addition of the polymerizable monomer and the polymerization catalyst. In this method, the molecular layer serves as a selective polymerization site for the polymerizable monomer.

As the above-mentioned surface active agent and / or surface active polymer, most of those generally used as low molecular weight surface active agents or high molecular weight surface active agents can be used. The surfactant and / or the surfactant polymer should not polymerize with each other under the polymerization conditions of the polymerizable monomer so that the molecular layer formed on the surface of the material particles provides a uniform polymerization field. Is preferred. However, even in this case, the produced polymer molecule may be bonded to the surfactant and / or the surfactant polymer by, for example, chain transfer during polymerization.

Examples of such surfactants and / or surface active polymers include higher fatty acid salts such as sodium oleate; alkylsulfates such as sodium dodecylsulfate; alkylsulfonates such as sodium stearylsulfonate; dodecyl. Alkylaryl sulfonates such as sodium benzenesulfonate; anionic surfactants such as sulfosuccinate ester salts such as dioctyl sodium sulfosuccinate: alkyl polyoxyethylene ethers; alkylphenyl polyoxyethylene ethers; polyethylene glycol alkyl ethers; Alkylcarbonyloxy polyethylenes; N,
N-di (polyoxyethylene) alkane amides; N,
N-di (alkanol) alkane amides; fatty acid polyhydric alcohol esters such as polyethylene glycol fatty acid ester, sorbitan fatty acid ester, fatty acid monoglyceride, fatty acid sucrose ester; nonionic surfactants such as fatty acid polyhydric alcohol polyoxyethylene ethers: Higher alkyl ammonium salts such as dodecyl ammonium chloride; quaternary N-alkyl pyridinium salts such as dodecyl pyridinium chloride; quaternary N-alkyl picolinium salts such as dodecyl picolinium chloride; quaternary alkyl such as cetyl trimethyl ammonium bromide Ammonium salts; quaternary alkyl imidazolinium salts; quaternary polyoxyethylene alkyl diammonium salts; quaternary polyoxyethylene alkyl ammonium salts Quaternary alkoxypropyl ammonium salts; cationic surfactants such as organic acids or inorganic acid salts of alkyl propylene diamines: alkyl amine oxides; alkyl glycines; alkyl alanines; alkyl betaines; amphoteric ions such as alkyl imidazolines Surfactants: Cellulose derivatives such as carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose; polyvinylpyrrolidone; polyvinyl alcohol; sodium polycarboxylic acid;
Mention may be made of surface-active polymers such as polyacrylic acid. These surfactants and / or surfactant polymers may be used alone or in admixture of two or more.

The amount of the surfactant and / or the surface active polymer used is preferably 0.05 to 50 parts by weight, more preferably 0.1 to 50 parts by weight, based on 100 parts by weight of the colored substrate particles.
20 parts by weight, particularly preferably 0.1 to 10 parts by weight. When the amount of the surfactant and / or the surfactant polymer used is less than 0.05 parts by weight, an effective surfactant and / or molecule of the surfactant polymer which serves as a selective polymerization field on the surface of the colored substrate particles. In some cases, it may be difficult to form a layer, and when it exceeds 50 parts by weight, it may be difficult to suppress the formation of a polymer that is present separately from the colored substrate particles.

The formation of the molecular layer of the surfactant and / or the surface-active polymer on the surface of the colored substrate particles in the third method is carried out by dispersing the colored substrate particles and the surfactant and / or the surface active agent in a dispersion medium. It can be carried out by contacting with a polymer and adsorbing a surfactant and / or a surfactant polymer on the surface of the colored substrate particles. The colored substrate particles on which the molecular layer of the surfactant and / or the surface-active polymer is formed in this manner can be directly used as a dispersion liquid for the polymerization of the polymerizable monomer in the next step, In some cases, the colored substrate particles may be separated from the dispersion medium and then redispersed in another dispersion medium.

In this case, the dispersion medium disperses the colored substrate particles and forms a molecular layer of the surfactant and / or the surface active polymer, which serves as a selective polymerization field, on the surface of the particles. It is used for the purpose of dispersing the polymerizable monomer polymerized in the process. Examples of such a dispersion medium include water; alcohols, ketones, ethers,
Examples thereof include organic solvents such as esters and amines. These dispersion media are appropriately selected according to the type of the colored substrate particles, the surfactant and / or the surface active polymer, the polymerizable monomer, the polymerization catalyst, etc., and are mainly composed mainly of water,
If necessary, the organic solvent may be added for use.

The amount of these dispersion media used is preferably 100 to 1,000 per 100 parts by weight of the colored substrate particles.
10,000 parts by weight, more preferably 100-100,
000 parts by weight, particularly preferably 500 to 10,000 parts by weight.

In the third method, since the surfactant and / or the surface-active polymer itself has a dispersion improving action, it is not necessary to add another dispersion improving agent during the polymerization of the polymerizable monomer. In some cases, another dispersion improver may be added. Such other dispersion improver is appropriately selected and used from the above-mentioned surfactant and / or surfactant polymer.

When the polymerizable monomer and the polymerization catalyst are added, the polymerizable monomer and the polymerization catalyst may be added at the same time or after the addition of either the polymerizable monomer or the polymerization catalyst. The other may be added.

Examples of the polymerizable monomer used in the third method include those similar to the polymerizable monomer used in the graft copolymerization in the second method.

The amount of these polymerizable monomers used varies depending on the film thickness of the organic high molecular weight polymer that coats the surface of the colored substrate particles, but is usually 100 parts by weight of the colored substrate particles.
It is 0.5 to 1000 parts by weight, preferably 1 to 100 parts by weight.

Further, examples of the polymerization catalyst used for the polymerization of the polymerizable monomer include those used for the graft copolymerization in the second method.

The amount of the polymerization catalyst used is 100
It is generally 0.01 to 10 parts by weight, preferably 0.05 to 5 parts by weight, based on parts by weight.

The polymerization conditions in the third method will vary depending on the type of polymerizable monomer, polymerization catalyst, dispersion medium, etc.
The polymerization temperature is usually about 0 to 100 ° C., and the polymerization time is usually about 10 minutes to 48 hours.

In this way, the polymerizable monomer is polymerized in the state where the molecular layer of the surfactant and / or the surface-active polymer is formed on the surface of the colored substrate particles, whereby the colored substrate particles are obtained. The surface layer of the surface active agent and / or the surface active polymer serves as a selective polymerization field, and the surface of the colored substrate particles is firmly covered with a uniform coating layer of the organic polymer. Will be done.

In the third method, depending on the case,
The polymerization of the polymerizable monomer can also be carried out by irradiating with light in the presence or absence of the polymerization catalyst. In this photopolymerization, the same sensitizer as that used in the graft copolymerization in the second method is usually used.

The thickness of the organic polymer coating layer of the colored composite particles obtained by the first to third methods described above in detail is
Although it can be appropriately set according to desired properties, intended use, etc. of the obtained colored composite particles, it is usually 0.001 to 10 μm.
m, preferably 0.01 to 5 μm.

The average particle size (R ₃ ) of the colored composite particles obtained by the first to third methods is the average particle size of the colored base particles.
(R ₁ ), it can be appropriately set by adjusting the film thickness of the organic polymer coating layer, etc.
m, and particularly preferable average particle diameter (R ₃ ) as the colored spacer particles is 2 to 10 μm.

Furthermore, the standard deviation of the particle size distribution of the colored composite particles obtained by the first to third methods is ± 1 of the average particle size by appropriately setting the particle size distribution of the colored base material particles.
It can be 0% or less. The standard deviation of the particle size distribution is preferably ± 5% or less, more preferably ± 3% or less. Particularly, as the colored spacer particles for keeping the thickness of the liquid crystal layer constant, the smaller the standard deviation of the particle size distribution is, the more preferable.

In the colored composite particles thus obtained, the bonding between the core fine particles and the colored metal compound layer and the bonding or bonding between the colored metal compound coating layer and the organic polymer coating layer are both achieved. Therefore, even if the colored composite particles are dispersed in, for example, water and subjected to ultrasonic waves, the colored metal compound layer is no longer peeled from the core fine particles, and the organic polymer coating layer is no longer colored particles. Does not peel off or fall off.

Further, in the present invention, the original properties of the core fine particles are not impaired at all, and the strength and heat resistance of the entire colored composite particles are as excellent as those of the core fine particles or the colored base particles themselves. be able to. Moreover, regarding the colored composite particles, the particle size distribution of the colored base particles can be substantially maintained, and a sufficient degree of coloring can be achieved.

Therefore, when the colored composite particles of the present invention are used especially as colored spacer particles, the thickness of the liquid crystal layer can be kept constant, the coloring component has a sufficient degree of coloring, and the coloring component composed of a coloring metal compound is contained. There is no risk of elution or migration into the liquid crystal component, and the impurities due to the coloring agent do not pose any problem as in the past, and the colored metal compound coating layer and the organic polymer are also present during the production and use of the LCD. The polymer coating layer does not peel off or fall off,
Further, since the organic high molecular polymer coating layer is present in the outermost layer, it has the required thermal adhesiveness, and the required characteristics such as the light shielding performance can be stably exhibited.

Further, as described above, not only the manufacturing process of the colored substrate particles of the present invention is an industrially extremely advantageous process, but also the organic high molecular polymer as shown in the first to third methods. Regarding the method for forming the coating layer, the first method can be carried out by the same operation as the kneading operation of a usual organic high-molecular polymer, and the second and third methods are the treatment of a dispersion liquid of colored base particles. Also, the method can be carried out in a reaction system that is easy to operate, and both methods have high efficiency of producing desired colored composite particles. Therefore, the colored composite particles of the present invention can be industrially extremely advantageously manufactured through all the steps.

[0092]

EXAMPLES Next, the present invention will be described more specifically by way of examples. However, the present invention does not exceed the gist of the invention.
There is no limitation to these examples. Example 1 100 crosslinked divinylbenzene polymer particles having an average particle size of 5.0 μm and a standard deviation of the particle size distribution of ± 1% of the average particle size.
g, polyvinylpyrrolidone 2 g, tetra-n-titanate
After sufficiently stirring 35 g of butyl, 7 liters of ethanol and 100 ml of water with a homogenizer, 8
It heated at 0 degreeC for 4 hours, and hydrolyzed the tetra-n-butyl titanate. The reaction mixture was then cooled to room temperature and centrifuged to settle the particles. Then, the supernatant liquid was separated, distilled water was added, and the mixture was thoroughly stirred with a homogenizer to uniformly disperse the particles, and the centrifugation operation was repeated 5 times. Then, the obtained particles were dried at room temperature. When the particles thus obtained were observed with a scanning electron microscope, the average particle size was 5.3 μm, the standard deviation of the particle size distribution was ± 1% of the average particle size, and the core microparticles with respect to the outer diameter of the colored base material particles. The spherical composite particles had a diameter ratio of 0.94 and a uniform coating layer. When the composite particles were analyzed by infrared absorption spectrum, X-ray diffraction, thermogravimetric analysis, elemental analysis and electrophoresis, the core was a crosslinked divinylbenzene polymer particle and the shell was titanium oxide (IV) (TiO ₂ ).
Was confirmed to consist of.

Composite particles 100 obtained as described above
g was heated from room temperature to 300 ° C. at a heating rate of 10 ° C./min in a hydrogen atmosphere, held at 300 ° C. for 3 hours, and then cooled to room temperature at a cooling rate of 10 ° C./min. , Black composite particles were obtained. The obtained composite particles have an average particle size of 5.2 μm, and the standard deviation of the particle size distribution is ± of the average particle size.
1%, the ratio of the core fine particle diameter to the particle outer diameter is 0.96
The spherical composite particles had a uniform coating layer. Further analysis of the composite particles as described above,
It was confirmed that the core was a crosslinked divinylbenzene polymer particle and the shell was a composite particle composed of titanium (II) oxide (Ti0). This composite particle is referred to as a colored base particle A.

100 g of the colored substrate particles A and a fine powder of a copolymer of 83 parts by weight of styrene and 17 parts by weight of butyl acrylate (glass transition temperature 60 ° C., average particle size 0.16 μm).
m, standard deviation of particle size distribution is ± 5% of average particle size) 15 g
Was mixed for 5 minutes with an OM diizer of a hybridization system manufactured by Nara Machinery Co., Ltd. to form an ordered mix char. This ordered mixture was mixed for 7 minutes by the hybridizer of the hybridization system, and the copolymer fine particles were adhered to the surface of the colored base material particle A to form a composite. These particles are called colored composite particles B.

Colored composite particles B thus obtained
In the above, the copolymer fine particles were melted and integrated, whereby the particle surface was covered smoothly, and the average particle diameter was 5.3 μm. The standard deviation of the particle size distribution of the colored composite particles B was ± 1% of the average particle size, and the particle size distribution was the same as that of the crosslinked divinylbenzene polymer particles that are the core particles, and had a narrow particle size distribution.

The colored composite particles B were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly step under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, and the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, and the spacer particles do not move even when the liquid crystal is injected. Was excellent in strength and heat resistance.

Example 2 100 g of colored substrate particles A and fine powder of polymethylmethacrylate (glass transition point: 130 ° C., average particle size: 0.2 μ)
m, the standard deviation of the particle size distribution is ± 5% of the average particle size) 15 g was mixed in the same manner as in Example 1 to mix the polymethyl methacrylate fine particles with the surface of the colored base material particles A. Clothed and compounded. This particle is referred to as a colored composite particle C.

Colored composite particles C thus obtained
In the above, the poly (methyl methacrylate) fine particles were melted and integrated, whereby the particle surface was covered smoothly, and the average particle diameter was 5.3 μm. Further, the standard deviation of the particle size distribution of the colored composite particles C was ± 1% of the average particle size, and the particle size distribution was the same as that of the crosslinked divinylbenzene polymer particles as the core particles, and had a narrow particle size distribution.

Further, the colored composite particles C were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, the spacer particles do not move even when liquid crystal is injected, and the colored composite particles C as a whole are Was excellent in strength and heat resistance.

Example 3 100 crosslinked divinylbenzene polymer particles having an average particle size of 5.0 μm and a standard deviation of the particle size distribution of ± 1% of the average particle size.
g, polyvinylpyrrolidone 2 g, ferric chloride 50 g, urea 100 g, concentrated hydrochloric acid 25 g, and water 7 liters were sufficiently stirred with a homogenizer, and then heated at 100 ° C. for 4 hours to hydrolyze ferric chloride. The reaction mixture was then cooled to room temperature and centrifuged to settle the particles.
Then, the supernatant liquid was separated, distilled water was added, and the mixture was thoroughly stirred with a homogenizer to uniformly disperse the particles, and the centrifugation operation was repeated 5 times. Then, the obtained particles were dried at room temperature. When the particles thus obtained were observed with a scanning electron microscope, the average particle size was 5.3 μm, the standard deviation of the particle size distribution was ± 1% of the average particle size,
The ratio of the core fine particle diameter to the particle outer diameter was 0.94, and the particles were spherical composite particles having a uniform coating layer. When the composite particles were analyzed by infrared absorption spectrum, X-ray diffraction, thermogravimetric analysis, elemental analysis and electrophoresis, the core was a crosslinked divinylbenzene polymer particle and the shell was α-iron oxide (I
II) It was confirmed that the particles were composite particles composed of (Fe ₂ O ₃ ).

100 g of the composite particles were placed in a hydrogen atmosphere,
After the temperature was raised from room temperature to 320 ° C. at a rate of 10 ° C./min, the temperature was kept at 320 ° C. for 3 hours and then cooled to room temperature at a rate of 10 ° C./min to obtain black composite particles. It was The obtained composite particles have an average particle size of 5.2 μm, a standard deviation of particle size distribution is an average particle size of ± 1%, a ratio of the core fine particle diameter to the particle outer diameter is 0.96, and a spherical shape having a uniform coating layer. It was a composite particle of. Further analysis of this composite particle in the same manner as above confirmed that the core was a crosslinked divinylbenzene polymer particle and the shell was a composite particle composed of iron (III) iron (II) (Fe ₃ O ₄ ). It was The composite particles are referred to as colored base material particles D.

100 g of the colored substrate particles D and a fine powder of a copolymer of 83 parts by weight of styrene and 17 parts by weight of butyl acrylate (glass transition temperature 60 ° C., average particle size 0.16 μm).
m, the standard deviation of the particle size distribution is ± 5% of the average particle size) 15 g was mixed in the same manner as in Example 1 to bond the copolymer fine particles to the surface of the colored substrate particles D. And then compounded. This particle is called a colored composite particle E.

Colored composite particles E thus obtained
In the above, the copolymer fine particles were melted and integrated, whereby the particle surface was covered smoothly, and the average particle diameter was 5.3 μm. The standard deviation of the particle size distribution of the colored composite particles E was ± 1% of the average particle size, and the particle size distribution was the same as that of the divinylbenzene polymer particles as the core particles, and had a narrow particle size distribution.

The colored composite particles E were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, and the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, and the spacer particles do not move even when the liquid crystal is injected. Was excellent in strength and heat resistance.

Example 4 100 g of colored substrate particles D and fine powder of polymethylmethacrylate (glass transition point 130 ° C., average particle size 0.2 μ)
m, the standard deviation of the particle size distribution is ± 5% of the average particle size) 15 g was mixed in the same manner as in Example 1, and the polymethylmethacrylate fine particles were adhered to the surface of the colored substrate particles D. And then compounded. These particles are called colored composite particles F.

Colored composite particles F thus obtained
In the above, the poly (methyl methacrylate) fine particles were melted and integrated, whereby the particle surface was covered smoothly, and the average particle diameter was 5.3 μm. Further, the standard deviation of the particle size distribution of the colored composite particles F was ± 1% of the average particle size, and the particle size distribution was the same as that of the crosslinked divinylbenzene polymer particles as the core particles, and had a narrow particle size distribution.

The colored composite particles F were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, and the spacer particles do not move even when the liquid crystal is injected. Was excellent in strength and heat resistance.

Example 5 100 g of the colored substrate particles A and 1 liter of water were sufficiently stirred with a homogenizer, 1 g of γ-methacryloxypropyltriethoxysilane was added, and the mixture was stirred at room temperature for 1 hour. Then, in the reaction mixture, 20 g of styrene, 2,
0.5 g of 2'-azobisisobutyronitrile and 5 of water
The emulsion obtained by sonicating 0 g of the mixture was added and heated at 80 ° C. for 24 hours. Then the reaction mixture was cooled to room temperature and centrifuged to settle the particles. Then, after separating the supernatant, isopropanol was added, and the mixture was thoroughly stirred with a homogenizer to uniformly disperse the particles, followed by centrifugation. This washing operation was repeated 5 times. Then, the obtained particles were dried at room temperature. This particle is referred to as a colored composite particle G. The thus-obtained colored composite particles G have a particle surface smoothly covered with a layer of polystyrene graft-copolymerized, and have an average particle diameter of 5.3 μm.
It was m. Further, the standard deviation of the particle size distribution of the colored composite particles G was ± 1% of the average particle size, and the particle size distribution was the same as that of the divinylbenzene polymer particles as the core particles and had a narrow particle size distribution.

The colored composite particles G were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, and the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, the spacer particles do not move even when liquid crystal is injected, and the colored composite particles G as a whole are Was excellent in strength and heat resistance.

Example 6 100 g of the colored substrate particles D and 1 liter of water were sufficiently stirred with a homogenizer, 1 g of vinyltrimethoxysilane was added, and the mixture was stirred at room temperature for 1 hour. Then, an emulsion obtained by ultrasonically treating a mixture of 20 g of methyl methacrylate, 0.5 g of benzoyl peroxide and 50 g of water was added to the reaction mixture, and heated at 80 ° C. for 24 hours. Then the reaction mixture was cooled to room temperature and centrifuged to settle the particles. Then, after separating the supernatant, isopropanol was added, and the mixture was thoroughly stirred with a homogenizer to uniformly disperse the particles, followed by centrifugation. This washing operation was repeated 5 times. Then, the obtained particles were dried at room temperature. This particle is referred to as a colored composite particle H. The thus-obtained colored composite particles H had a particle surface smoothly covered with a layer of polymethylmethacrylate graft-copolymerized, and had an average particle size of 5.3 μm. The standard deviation of the particle size distribution of the colored composite particles H was ± 1% of the average particle size, and the particle size distribution was the same as that of the divinylbenzene polymer particles as the core particles, and had a narrow particle size distribution.

The colored composite particles H were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, and the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, the spacer particles do not move even when liquid crystal is injected, and the colored composite particles H as a whole are Was excellent in strength and heat resistance.

Example 7 100 g of colored substrate particles A, 30 g of cetyltrimethylammonium bromide and 1 liter of water were sufficiently stirred with a homogenizer, and then 20 g of styrene, 0.5 g of 2,2′-azobisisobutyronitrile and 50 g of water were added. Add the emulsion obtained by sonicating the mixture,
Heated at ° C for 24 hours. Then the reaction mixture was cooled to room temperature and centrifuged to settle the particles. Then, after separating the supernatant, isopropanol was added, and the mixture was thoroughly stirred with a homogenizer to uniformly disperse the particles, followed by centrifugation. This washing operation was repeated 5 times. Then, the obtained particles were dried at room temperature. This particle is referred to as a colored composite particle I. The thus-obtained colored composite particles I have a particle surface smoothly covered with a layer of polystyrene,
The average particle size was 5.3 μm. The standard deviation of the particle size distribution of the colored composite particles I is ± 1% of the average particle size,
The particle size distribution was the same as that of the divinylbenzene polymer particles as the core particles, and had a narrow particle size distribution.

The colored composite particles I were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, and the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, and the spacer particles do not move even when liquid crystal is injected. Was excellent in strength and heat resistance.

Example 8 Colored base particle D100 g, sodium oleate 50 g
After thoroughly stirring 1 liter of water and a homogenizer with a homogenizer, an emulsion obtained by sonicating a mixture of 20 g of methyl methacrylate, 0.5 g of benzoyl peroxide and 50 g of water was added, and the mixture was heated at 80 ° C. for 24 hours.
Then the reaction mixture was cooled to room temperature and centrifuged to settle the particles. Next, the supernatant liquid was separated, isopropanol was added, and the mixture was thoroughly stirred with a homogenizer to uniformly disperse the particles, and the centrifugation operation was repeated 5 times. Then, the obtained particles were dried at room temperature. This particle is referred to as a colored composite particle J. The thus-obtained colored composite particles J had a particle surface smoothly covered with a layer of polymethylmethacrylate, and had an average particle diameter of 5.3 μm. The standard deviation of the particle size distribution of the colored composite particles J was ± 1% of the average particle size, and the particle size distribution was the same as that of the divinylbenzene polymer particles as the core particles, and had a narrow particle size distribution.

The colored composite particles J were centrifugally washed in isopropyl alcohol, dried, and then pressed as colored spacer particles in the LCD substrate assembly process under the conditions of 160 ° C. and 1.0 Kgf / cm ^2. The distance between the transparent electrode substrates is kept constant at 5 μm, and the spacer particles are firmly fixed to the upper and lower transparent electrode substrates, and the spacer particles do not move even when liquid crystal is injected. Was excellent in strength and heat resistance.

[0116]

The colored composite particles of the present invention are excellent in strength and heat resistance, have a narrow particle size distribution and a sufficient degree of coloring, have no elution or migration of the coloring component into the liquid crystal component, and have an adhesive property. And the like, and is particularly suitable as a colored spacer particle. Moreover, the colored composite particles can be manufactured extremely advantageously industrially.

Front page continuation (72) Inventor Kazuo Nishimoto 2-11-24 Tsukiji, Chuo-ku, Tokyo Japan Synthetic Rubber Co., Ltd. Naru Rubber Co., Ltd.

Claims (1)

[Claims] 1. A colored metal compound coating layer serving as a shell is provided on the core fine particles by a hydrolysis reaction of a hydrolyzable metal salt and / or metal alkoxide in a solution, and a heat treatment is carried out if necessary. Colored composite particles having an organic polymer coating layer formed on the surface of the colored base material particles thus obtained.