JPH1068954A - Color fine particle, spacer for liquid crystal display element and liquid crystal display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain color fine particles which show good display quality without causing abnormal orientation when the particles are used as a spacer for a liquid crystal display element, by controlling the peak height ratio of a specified mass number to another specified mass number to a specified value or lower in the surface analysis using a time-of-flight secondary ion mass spectrometer (TOF-SIMS). SOLUTION: The color fine particles have 1.0 to 10μm average particle size and the surface analysis of the particles by TOF-SIMS shows that the peak height ratio of the mass number 16 (MASS-16) to the mass number 13 (MASS-13) is (MASS-16)/(MASS-13)<=0.8. If the peak height ratio in the surface analysis by TOF-SIMS exceeds 0.8, it means that the amt. of hydroxyl groups on the surface of color fine particles is too large and that the particles cause abnormal orientation when used as a spacer for a liquid crystal display element. Thereby, the ratio is specified to the range above described.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to colored fine particles which can be suitably used as a spacer for a liquid crystal display element having good contrast, a spacer for the liquid crystal display element, and a liquid crystal display element.

[0002]

2. Description of the Related Art Liquid crystal display devices are widely used in personal computers, portable electronic devices, and the like, and it is desired to further increase the display contrast of an image with an increase in image quality and area.

[0003] A liquid crystal display element is usually manufactured by arranging two transparent substrates with electrodes so that the electrodes face each other, and sealing a liquid crystal between the two substrates. In order to keep the distance between the two substrates constant, a spacer is generally used. However, if a transparent spacer is used, the display contrast is reduced. Therefore, a colored spacer is used to prevent a reduction in the display contrast of an image. It is becoming.

As a method for producing such a colored spacer, for example, Japanese Patent Application Laid-Open No. 1-144429 discloses a method in which the surface of fine particles is treated with an acid and then dyed with a dye. Further, Japanese Patent Application Laid-Open No. 3-33165 discloses a method in which the dyed fine particles are further treated with a silane coupling agent. Japanese Patent Application Laid-Open No. 7-11005 discloses a method of treating fine particles with osmium oxide, ruthenium oxide, or the like. In addition, a method of coating the surface of glass beads with a metal oxide film is known.

[0005] Another method for producing a colored spacer is to disperse a polymerizable monomer in which a pigment is dispersed in water in the presence of a suitable dispersion stabilizer, and to stir at a high speed with a homogenizer or the like to obtain an appropriate particle size. Is formed and then polymerized. It is necessary to add a dispersion stabilizer to prevent re-coalescence of particles, and JP-A-5-310807 discloses that by using a water-soluble polymer such as polyvinyl alcohol as such a dispersion stabilizer, It is disclosed that fine particles can be formed stably, coalescence of the fine particles can be prevented, and a required particle size can be obtained.

[0006] On the other hand, it has been well known that, in a liquid crystal display device, the orientation of liquid crystal molecules becomes irregular at the interface between the liquid crystal and the spacer, and the display quality may be degraded. Particularly, in a liquid crystal display device using a super twisted nematic liquid crystal (STN liquid crystal), which has been growing in demand in recent years, such an abnormal alignment phenomenon of the liquid crystal is likely to occur.

When such abnormal alignment occurs, when the liquid crystal display element is turned on, a white area called light leakage (also called “domain”) appears around the spacer. When this light leakage occurs around many spacers,
It looks as if the white line connects many spacers. This white line is called a disclination line and is well known as one that characterizes abnormal alignment of liquid crystal molecules. When many disclination lines appear, the contrast of the liquid crystal display element decreases,
The display quality will be significantly reduced.

The phenomenon of light leakage occurs because the orientation of the liquid crystal at the interface between the liquid crystal and the spacer is different from the orientation of the liquid crystal in a region other than the interface. The cause of such abnormal orientation of the liquid crystal at the interface of the spacer is that the surface of the spacer has some restrictive force on the liquid crystal.
Unless the regulating force on the liquid crystal is reduced or eliminated, light leakage cannot be solved, and contrast is significantly impaired.

It has been found that in the conventional colored spacer, the abnormal orientation around the spacer is large, and as a result, it does not contribute to the improvement of the image quality, but lowers the contrast as compared with the transparent spacer. Although the detailed mechanism of the abnormal orientation around the spacer is unknown, it has been found that the surface condition of the spacer is particularly important.

Since the surface of a conventional colored spacer is covered with a dye or a metal oxide film, the surface has a high oxygen content and often has a strong hydrophilic property. Some of them are hydroxyl groups which exhibit a particularly strong alignment regulating force on the liquid crystal.

In the case of a colored spacer formed by the suspension polymerization method, polyvinyl alcohol is graft-reacted with a polymerizable monomer during polymerization to form a polyvinyl alcohol layer on the surface of the fine particles. Since it cannot be removed even by a suitable washing method, it has hydroxyl groups on its surface.

In the dyeing method, polyvinyl alcohol formed on the surface is denatured with an acid or the like and dyed with a dye or the like. However, all the hydroxyl groups cannot be denatured, and the surface must have a hydroxyl group. Become. In these colored fine particles, it has been found that the hydroxyl group causes light leakage around the spacer, which causes a decrease in the contrast of the liquid crystal display element.

As a method for preventing such light leakage,
By coating the surface of the spacer with a material that has a strong hydrophobic property such as an alkyl group and has little ability to regulate the alignment of the liquid crystal, light leakage around the spacer is prevented, and contrast is reduced. It is reported that it can be dramatically improved. However, there has been no index indicating the degree of hydrophobicity of the surface sufficient to prevent light leakage, and it has been difficult to industrially efficiently produce a colored spacer having a surface coated with an alkyl group.

[0014]

SUMMARY OF THE INVENTION In view of the above situation, the present invention makes it possible to easily evaluate the degree of surface hydrophobicity,
An object of the present invention is to provide colored fine particles having no abnormal orientation when used as a spacer for a liquid crystal display element and having good display quality, and a liquid crystal display element.

[0015]

The present invention relates to colored fine particles having an average particle size of 1.0 to 10 μm,
In surface analysis by SIMS, mass number 13 (MAS
S-13) and the peak height ratio (MASS-16) / (MASS-13) of mass number 16 (MASS-16),
The colored fine particles have a ratio of 0.8 or less.
Hereinafter, the present invention will be described in detail.

[0016] The colored fine particles of the present invention are prepared by TOF-SIMS.
(Time-of-flight secondary ion mass spectrometer (Time of
Flight Secondion Ion Mass
(Spectol)), the mass number 13 (MASS-13) and the mass number 16 (MASS-1)
6) and the ratio of the peak height (MASS-16) / (MASS)
-13) is 0.8 or less. When the ratio of the peak heights is 0.
If it exceeds 8, the amount of hydroxyl groups on the surface of the colored fine particles increases, and when used as a spacer for a liquid crystal display element, an abnormal alignment is caused.

In the present invention, TOF-SIMS analyzes fragments of secondary ions generated by applying an ion stream to the surface of colored fine particles, and utilizes the fact that different masses have different times to pass a fixed distance. It is to identify each mass number.

In the present invention, the above-mentioned TOF-SIM is prepared while the colored fine particles are scattered on a clean silicon wafer.
The surface analysis was performed by S and the mass number was 13 (MASS-1).
3) and measure the peak height of mass number 16 (MASS-16).

In the present invention, the peak height ratio (M
When ASS-16) / (MASS-13) is 0.8 or less, it can be estimated that the surface of the colored fine particles is covered with an alkyl group.

The colored fine particles of the present invention have an average particle size of 1.0
〜１０10 μm. If it is less than 1.0 μm, the gap accuracy of the liquid crystal cell is reduced when used as a spacer for a liquid crystal display element, and if it is more than 10 μm, the gap of the liquid crystal cell cannot be obtained, so that it is limited to the above range.

The method for producing the colored fine particles of the present invention includes:
For example, there is a method of coating an alkyl group on the surface of fine particles obtained by dispersing a pigment in a polymerizable monomer and polymerizing the pigment. Examples of the polymerization method include a suspension polymerization method.

The polymerizable monomer is not particularly limited, and for example, polyfunctional acryl and the like can be used.
The polyfunctional acrylic is not particularly limited, for example,
Tetramethylolmethanetetra (meth) acrylate,
Tetramethylolmethane tri (meth) acrylate, tetramethylolmethane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate Acrylate, glycerol di (meth) acrylate, polyethylene glycol di (meth)
Acrylate and polypropylene glycol di (meth) acrylate.

In the present invention, a polymerizable monomer other than the above-mentioned polyfunctional acryl may be used. Examples of the polymerizable monomer other than the above-mentioned polyfunctional acryl include α-methylstyrene, p-methoxy Examples include styrene, styrene, divinylbenzene, trivinylbenzene, vinyltoluene, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, and the like.

In the above suspension polymerization method, usually, a component containing a polymerizable monomer is dispersed in an aqueous medium in which the polymerizable monomer is not dissolved, and the resulting mixture is suspended in fine particles. Polymerize using an agent. Examples of the aqueous medium include water. Usually, a dispersion stabilizer is added to the aqueous medium in order to allow the fine particles to be stably present. Examples of the dispersion stabilizer include water-soluble polymers such as polyvinyl alcohol, copolymers of ethylene glycol and propylene glycol, and surfactants.

As the above-mentioned polymerization initiator, those used in ordinary suspension polymerization can be used, and examples thereof include organic peroxides and azonitrile compounds. Examples of the peroxide include acetyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, t
-Butyl hydroperoxide and the like. Examples of the azonitrile compound include, for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis-2,
4'-dimethylvaleronitrile, 2,2'-azobismethylbutyronitrile, and the like.

The polymerization initiator is preferably used in an amount of 0.01 to 20 parts by weight based on 100 parts by weight of the polymerizable monomer. If the amount is less than 0.01 part by weight, the polymerization rate may decrease. If the amount is more than 20 parts by weight, there is no certain effect. The polymerization temperature is preferably from 40 to 100 ° C., although it depends on the type of polymerization initiator used. When the temperature is lower than 40 ° C., the polymerization rate is low, and when it exceeds 100 ° C., it becomes difficult to control the polymerization reaction. The polymerization time is preferably 30 minutes to 10 hours. If the time is less than 30 minutes, the polymerization rate is low and 10
No extra time is required.

When the colored fine particles of the present invention are produced by the above-mentioned suspension polymerization method, for example, a mixture comprising the above-mentioned polymerizable monomer, the above-mentioned polymerization initiator, a pigment, the above-mentioned dispersion stabilizer and the like is mixed with a high-speed stirrer or the like. After obtaining a dispersion liquid in which the pigment and the polymerization initiator are dispersed in the polymerizable monomer, 100 parts by weight of the dispersion liquid is added to 200 to 3000 parts by weight of an aqueous medium in which the dispersion stabilizer is dissolved. Can be produced by further dispersing the mixture and stirring the mixture with a stirring blade or the like.
By changing the shape and size of the stirring blade, the stirring speed, and the like, a suspended particulate having a required particle size can be obtained. The average particle size of the suspended particulate is preferably 0.5 to 100 μm.

By heating the water-soluble medium in which the polymerizable monomer thus obtained is dispersed, colored fine particles can be obtained. The colored fine particles thus obtained have an average particle diameter of about 0.1 to 100 μm, and can be classified into 0.1 to 10 μm colored fine particles by classification.

The pigment contained in the colored fine particles is not particularly limited, and examples thereof include quinacrine red, para red, chlorinated para red, lytor rubin, pigment scar red, madder lake, alizarin maroon, heliobold, thioindigo, toluidine maroon, and carbadordi. Oxazine Bio Red, Red Lake C, Pyrazolone Red, Naphthol Red, Anthraquinone Red, Isoindolino Red, Anthraquinone Yellow, Benzidine Yellow, Hansa Yellow, Benzidine Yellow Toluidine, Benzidine Orange, Disazo Red, Dianisidine Orange, Pyranthrone Orange,
GR Perino Orange, Isoindolinone Yellow, Flapanthrone Yellow, Anthrapyrimidine Yellow, Nickel Azo Yellow, Phthalocyanine Blue, Phthalocyanine Green, Chlorinated Phthalocyanine Green, Brominated Phthalocyanine Green, Partially Brominated Chlorinated Phthalocyanine Green, Pigment Green B, Organic pigments such as induslon blue and aniline black; cadmium yellow, cadmium red, cadmium mercury red, chrome vermillion, lead cyanamide, antimony white, antimony red, titanium white, titanium yellow, lemon yellow, mars yellow, ocher, cobalt violet , Manganese violet, ultramarine, Berlin blue, cobalt blue, cerulean blue, black Beam green, emerald green, cobalt green, and inorganic pigments such as carbon black.

In the present invention, white pigments such as titanium dioxide, zinc white, lead white, and lithopone can be used as the above pigments. The pigments may be used alone or in combination of two or more. The particle diameter of the pigment is preferably 0.01 to 1 μm in terms of average particle diameter from the viewpoints of light transmittance, film surface uniformity, and the like. The content of the pigment in the colored fine particles of the present invention is preferably 1 to 25% by weight. If the amount is less than 1% by weight, the coloring becomes thin and the image quality cannot be improved. If the amount exceeds 25% by weight, the mechanical strength decreases.

In the suspension polymerization method, as a method of dispersing the pigment in the polymerized monomer, for example, a sand mill, a high-speed stirrer, or another method in which a mechanical shear force is applied can be used.

As a method of coating the surface of the colored fine particles thus obtained with an alkyl group, for example, a polymerizable monomer having a long-chain alkyl group, a silane coupling agent having an alkyl group, etc. A method of coating the surface of the colored fine particles with a polyvinyl alcohol covering the surface of the colored fine particles with a treating agent having an alkyl group.

Among these, as a method of reacting polyvinyl alcohol with a treating agent having an alkyl group, for example, a method utilizing an acetalization reaction with an aldehyde; a hydroxyl group of polyvinyl alcohol by monoisocyanate, acrylic acid chloride, methacrylic acid chloride or the like is used. And the method of denaturing the active hydrogen to eliminate the active hydrogen.

Examples of the silane coupling agent include ethyltrichlorosilane, propyltrichlorosilane, butyltrichlorosilane, amyltrichlorosilane, hexyltrichlorosilane, heptyltrichlorosilane, octyltrichlorosilane, lauryltrichlorosilane, and octadecyltrichlorosilane. No. When the silane coupling agent having an alkyl group is coated on the surface of the spacer, it is preferable to react 0.01 to 5 g of the silane coupling agent with 10 g of the colored fine particles.

The aldehyde used in the acetalization reaction includes, for example, aliphatic aldehydes such as formaldehyde, acetaldehyde, butyraldehyde, hexylaldehyde, cyclohexylaldehyde, octylaldehyde, lauryl aldehyde; benzaldehyde;
And aromatic aldehydes such as naphthyl aldehyde.

The amount of the aldehyde added is 1 g of the spacer.
Is preferably from 0.01 to 100 mmol. 0.0
If it is less than 1 mmol, hydroxyl groups are present on the surface of the spacer and abnormal orientation occurs. If it exceeds 100 mmol, it becomes difficult to remove the aldehyde in a later step.

The above acetalization reaction can be carried out, for example, by the following method. After dispersing the colored fine particles in water or a water / alcohol solvent, the reaction is carried out using an acid catalyst such as hydrochloric acid. The reaction temperature is 30 to 90 ° C and 1 to 10
The hydroxyl group is acetalized by reacting for a time.

The amount of the acid catalyst such as hydrochloric acid added is preferably 0.1 to 10% by weight based on the whole system. If the amount is less than 0.1% by weight, the reaction takes a long time, so that the spacer is liable to be deteriorated. If the amount exceeds 10% by weight, impurities are increased in the reaction system and it takes time for purification.

In the present invention, the reason why abnormal orientation can be prevented when the ratio of the peak height in the surface analysis by TOF-SIMS is 0.8 or less is not clear, but the MASS-13 is colored. Mass number of negative ion of carbon derived from alkyl group on the surface of fine particles is 13
MASS-16 represents the mass number 16 of the negative ion of oxygen derived from the hydroxyl group on the surface of the colored fine particles,
The ratio of the peak height (MASS-16) / (MASS-1
It is presumed that 3) represents the amount of hydroxyl groups relative to the amount of alkyl groups on the surface of the colored fine particles.

Since the colored fine particles of the present invention have a peak height ratio of 0.8 or less, most of the surface is covered with an alkyl group, and it is presumed that a small amount of hydroxyl groups is present. When used as a spacer for a liquid crystal display element, light leakage can be prevented. Further, since the spacer is a colored spacer, display quality, particularly, contrast can be improved.

The present invention 2 is a spacer for a liquid crystal display device using the colored fine particles of the present invention. The present invention 3
A liquid crystal display device using the liquid crystal display device spacer of the second aspect of the present invention. As the liquid crystal display element of the third aspect of the present invention,
For example, the thing shown in FIG. 1 etc. are mentioned, for example, it is produced as follows.

First, the opposing surfaces of the pair of transparent substrates 10
An insulating film 11 (for example, SiO ₂ ) is formed, and a transparent conductive film 12 (for example, ITO) is formed on the insulating film 11 of each substrate by patterning by photolithography. The transparent conductive film 12 of each of the above substrates
An alignment film 13 (for example, a polyimide film) is formed thereon.
Next, the liquid crystal display element spacers 9 are sprayed on the alignment film 13 on the substrate.

Thereafter, an adhesive layer is formed on the periphery of the substrate facing the above-mentioned substrate using a sealant 14 and bonded to the substrate on which the spacers are scattered.
Is injected between these substrates to form a liquid crystal cell. The liquid crystal display element 15 is obtained by providing a wiring in the liquid crystal cell.

The dispersion density of the spacers 9 for liquid crystal display elements is preferably from 10 to 1000 / mm ² . 1
If it is less than 0 cells / mm ² , the gap of the liquid crystal cell may not be formed, and if it exceeds 1000 cells / mm ² , the contrast may be reduced due to the spacer.

Since the liquid crystal display element of the present invention 3 uses the spacer for the liquid crystal display element of the present invention 2, it is difficult to see even when the liquid crystal cell is turned on, and there is almost no light leakage. Further, since the pigment contained in the spacer has no contamination property to the liquid crystal, high reliability can be obtained.

[0046]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

(1) Surface Analysis by TOF-SIMS The surface analysis of the colored fine particles was performed by TOF-SIMS (PHI-SIMS).
Evans TFS-2000), primary ion 69 Ga ⁺ , ion current ² μA, mass range 1 to 100
At 0 mass, an analysis area of 177 × 177 μm ² , a mesh was inserted into the surface of the sample to prevent charge, and the ratio of the peak heights of MASS-13 and MASS-16 was measured by random raster scanning using electron beam neutralization.

(2) Preparation of Liquid Crystal Cell An SiO ₂ film is deposited on one surface of a pair of transparent glass plates (150 mm × 150 mm) by a CVD method, and a transparent electrode substrate ITO is formed on the SiO ₂ film by sputtering.
TO was formed. Further, patterning was performed by lithography. A polyimide intermediate (LP-64, manufactured by Toray Industries, Inc.) was formed on the ITO film of the pair of transparent glass plates by spin coating, and baked at 280 ° C. for 90 minutes to form a polyimide alignment film. Thereafter, rubbing was performed in a direction at an angle of 240 degrees to each other when the polyimide alignment film and the liquid crystal molecules contacted each other. The spacers for the liquid crystal display elements of Examples 1 to 4 and Comparative Examples 1 and 2 were sprayed on one of the transparent substrates, and the other was sealed with a peripheral sealant (main agent SE45).
00, a curing agent T, manufactured by HAVENCHEMICAL Co., Ltd.) was printed by a screen printing method, a sealant was formed around the periphery, and both were adhered to each other, and then cured at 160 ° C. for 90 minutes to produce an empty cell. The gap at this time was 6.1 μm. A liquid crystal (S-811, manufactured by Merck) containing a predetermined amount of a chiral agent was injected into the thus obtained empty cell to prepare a liquid crystal cell, and further heat-treated at 95 ° C. for 30 minutes.

(3) Measurement of Abnormal Alignment The liquid crystal cell thus obtained was photographed with a microscope at a magnification of 200 times, and the state of light leakage was observed.
The voltage at the time of observation was 5.2 volts. Measurement of light leakage was measured and the spacer area S _B of the photo screen in the initial state, the area S _A that missing 90 of the spacer around after applying for 30 seconds to the cell a DC voltage of V light on the same screen , And the ratio (S _A / S _B ) was determined. If this value is within 1.5, the image quality does not decrease and the contrast does not decrease.

Example 1 Each of 45 parts by weight of divinylbenzene / tetramethylolmethanetetra (meth) acrylate was mixed, and 2 parts by weight of anthraquinone red / phthalocyanine blue / phthalocyanine green and 4 parts by weight of carbon black were further polymerized as pigments. 4 parts by weight of 2,2'-azobisisobutyronitrile were added as an agent, and
Dispersed for 0 minutes. 1 L of the coloring liquid thus prepared
Was added dropwise to 400 g of a 2% aqueous polyvinyl alcohol solution with stirring in a round bottom separable flask. Further stirring was carried out, and when the total particle size became 6 μm, the temperature was raised while refluxing nitrogen, and the reaction was carried out at 85 ° C. for 5 hours to obtain colored fine particles. The obtained colored fine particles were classified, and the average particle size was 8 μm.
10 g of colored fine particles having a particle diameter variation coefficient of 3% were obtained.

The colored fine particles 10 obtained as described above
g was immersed in 70 g of 2% aqueous hydrochloric acid, and a solution prepared by dissolving 3 g of lauryl aldehyde in 10 g of isopropyl alcohol was added dropwise with stirring. Thereafter, the temperature was raised to 50 ° C., the reaction was performed for 3 hours, and the mixture was filtered.
The treated spacer was immersed in the g solution and filtered. After the same operation was repeated 9 times, the product was immersed in 70 g of toluene and filtered. This operation was repeated four times, and after drying, colored fine particles having a surface coated with an alkyl group were obtained. TOF by the above method
-Surface analysis by SIMS, production of a liquid crystal cell, and measurement of abnormal orientation were performed. The results are shown in Table 1.

Example 2 3 g of lauryl aldehyde was added to isopropyl alcohol 10
Example 1 was repeated, except that a solution in which 5 g of octylaldehyde was dissolved in 10 g of isopropyl alcohol was used instead of the solution dissolved in 10 g, to obtain colored fine particles having a surface coated with an alkyl group. TOF-SIMS by the above method
Surface analysis, fabrication of a liquid crystal cell, and measurement of abnormal alignment. The results are shown in Table 1.

Example 3 37.5 parts by weight of divinylbenzene / tetramethylolmethanetetra (meth) acrylate / styrene were mixed, and 2 parts by weight each of anthraquinone red / phthalocyanine blue / phthalocyanine green and 4 parts by weight of carbon black were used as pigments. Are used as polymerization initiators,
4 parts by weight of 2'-azobisisobutyronitrile was added and dispersed by a sand mill for 30 minutes. The colored solution thus prepared was stirred in a 1 L round bottom separable flask for 2 hours.
% Ethylene glycol / propylene glycol copolymer (manufactured by Sanyo Chemical Co., Ltd., Merpol HA-2200) aqueous solution (400 g). Stirring is further performed to reduce the overall particle size to 6.
When the thickness reached μm, the temperature was raised while refluxing nitrogen.
The reaction was performed at 5 ° C. for 5 hours to obtain colored fine particles. The obtained colored fine particles were classified to obtain 10 g of colored fine particles having an average particle diameter of 6.1 μm and a variation coefficient of the particle diameter of 3%.

In a 300 mL round bottom separable flask,
Colored fine particles 10 obtained as described above under nitrogen reflux
g was dispersed in 100 g of toluene, and a solution of 1 g of propyltrichlorosilane dissolved in 10 g of toluene was added dropwise over 10 minutes. After reacting the reaction bath at a temperature of 70 ° C. for 3 hours, the mixture was filtered and washed with isopropyl alcohol. After drying in vacuum drying at 200 ° C. for 2 hours, colored fine particles having a surface coated with an alkyl group were obtained. TO with the above method
Surface analysis by F-SIMS, preparation of liquid crystal cell, and
The measurement of the abnormal orientation was performed. The results are shown in Table 1.

Example 4 The procedure of Example 3 was repeated except that a solution of 1 g of hexyltrichlorosilane in 10 g of toluene was used instead of a solution of 1 g of propyltrichlorosilane in 10 g of toluene. The coated colored fine particles were obtained. Surface analysis by TOF-SIMS by the above method,
Preparation of a liquid crystal cell and measurement of abnormal orientation were performed. The results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was carried out except that the particles were classified into colored fine particles having an average particle diameter of 6 μm and a coefficient of variation in particle diameter of 3%, and the surface was not subjected to acetalization treatment with lauryl aldehyde. I got The surface analysis by TOF-SIMS, the preparation of a liquid crystal cell, and the measurement of abnormal orientation were performed by the above method.
The results are shown in Table 1.

Comparative Example 2 37.5 parts by weight of divinylbenzene / tetramethylolmethanetetra (meth) acrylate / styrene were mixed, and 4 parts by weight of 2,2'-azobisisobutyronitrile was further added as a polymerization initiator. And dispersed in a sand mill for 30 minutes. The solution thus prepared was stirred in a 1 L round bottom separable flask with 2% ethylene glycol /
The solution was dropped into 400 g of an aqueous solution of a propylene glycol copolymer (Merpol HA-2200, manufactured by Sanyo Chemical Industries, Ltd.).
Further stirring was performed and the total particle size became 6 μm.
The temperature was raised while refluxing nitrogen, and the reaction was carried out at 85 ° C. for 5 hours to obtain transparent fine particles. Classify the obtained transparent fine particles,
10 g of transparent fine particles having an average particle diameter of 6.1 μm and a variation coefficient of the particle diameter of 3% were obtained.

The transparent fine particles 10 obtained as described above
g was added to 30 g of 95% concentrated sulfuric acid and heat-treated at 60 ° C. for 3 hours. After removing the sulfuric acid, washing was carried out sufficiently. 6 g of black base dye (Carotene Black, Hodogaya Chemical Co., Ltd.)
5 g of the acid-treated fine particles were added to a solution which was dissolved in 00 ml of water and adjusted to pH 4 with acetic acid, and stained at 95 ° C. for 10 hours. After filtering the dyeing solution, hot water washing was repeated to sufficiently remove impurities on the surface to obtain colored fine particles. T in the above method
Surface analysis by OF-SIMS, production of a liquid crystal cell, and measurement of abnormal alignment were performed. The results are shown in Table 1.

[0059]

[Table 1]

[0060]

Since the colored fine particles of the present invention are as described above, the degree of hydrophobicity of the surface can be easily evaluated. When used as a spacer for a liquid crystal display element, there is no abnormal alignment and the display quality is low. , A liquid crystal display element having a good can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of a liquid crystal display device of the present invention.

[Explanation of symbols]

 Reference Signs List 8 liquid crystal molecule 9 spacer for liquid crystal display element 10 transparent substrate 11 insulating film 12 transparent conductive film 13 alignment film 14 sealant

Claims (3)

[Claims] 1. A colored fine particle having an average particle size of 1.0 to 10 μm, and has a mass number of 13 (MASS-13) and a mass number of 16 (M) in surface analysis by TOF-SIMS.
ASS-16) and peak height ratio (MASS-16) /
(MASS-13) 0.8 or less. 2. A spacer for a liquid crystal display device, wherein the colored fine particles according to claim 1 are used. 3. A liquid crystal display device, wherein the liquid crystal display device spacer according to claim 2 is used.