JPH072913A - Colored fine polymer particle, its production, spacer for liquid crystal display element, and liquid crystal display element - Google Patents

Abstract

PURPOSE:To obtain deeply colored fine polymer particles which contain a pigment homogeneously dispersed therein and are excellent in mechanical strengths and solvent resistance (resistance to pigment extraction with an org. solvent), a spacer for liq. crystal display element capable of preventing degradation in display contrast, and a liq. crystal display element. CONSTITUTION:100 pts.wt. monomer component comprising 100-60wt.% compd. having at least three ethylenically unsatd. groups and 0-40wt.% compd. having two ethylenically unsatd. groups, 5-50 pts.wt. (meth)acrylonitrile, and a pigment are mixed homogeneously, suspended in a state of fine particles in an aq. medium, and polymerized, giving colored fine polymer particles. The particles are classified to adjust the particle sizes to give a spacer A for a liq. crystal display element. The spacer A is used by the usual method to give a liq. crystal display element 9 shown in the figure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored polymer fine particle used for a labeling material, a carrier for a diagnostic reagent, a spacer for a liquid crystal display device and the like, a manufacturing method thereof, a spacer for a liquid crystal display device and a liquid crystal display device.

[0002]

2. Description of the Related Art Conventionally, it is known to produce a colored polymer fine particle by suspension-polymerizing a polymerizable monomer in an aqueous medium in the presence of a pigment. As the polymerizable monomer, a monofunctional vinyl compound is generally used.

However, according to this type of conventional technique, it is difficult to uniformly disperse the pigment inside the polymer fine particles, and colored polymer fine particles uniformly colored in a dark color cannot be obtained.
In addition, mechanical strength and solvent resistance (the property that the pigment is not extracted by the organic solvent) are also poor.

In Japanese Patent Publication No. 4-59321, a polyfunctional vinyl compound is used as a polymerizable monomer, and 100 to 15% by weight of the polyfunctional vinyl compound and other polyfunctional vinyl compounds are used. Pigment (filler) treated to impart lipophilicity is mixed with a monomer consisting of 0 to 85% by weight of a lipophilic vinyl compound, and suspension polymerization is performed in an aqueous medium to give a colored polymer. A pre-process for obtaining fine particles is disclosed.

In the above-mentioned patent publication, the surface of the colored polymer particles is treated with the vinyl compound by suspension polymerization or emulsion polymerization in the presence of the colored polymer particles obtained in the preceding step. There is disclosed an invention relating to a colored polymer fine particle coated with the polymer of claim 1, whereby a pigment (filler) is substantially absent on the surface of the polymer fine particle.

On the other hand, Japanese Patent Laid-Open No. 57-189117 discloses a liquid crystal display device in which two transparent substrates with electrodes are arranged so that the electrodes face each other, and liquid crystal is sealed in the gaps between the substrates. There is disclosed an invention relating to a liquid crystal display device in which colored spacers such as colored plastic fine particles are scattered over the entire surface of the substrate in contact with the liquid crystal therein, thereby preventing a reduction in display contrast of the liquid crystal display device.

[0007]

However, in the former invention, the colored polymer fine particles obtained in the preceding step are
Although improvements in mechanical strength, dispersibility of the pigment, and solvent resistance are recognized, they are still not sufficiently satisfactory.

Moreover, in order to prevent the pigment from being substantially present on the surface of the fine polymer particles, the vinyl compound is suspension-polymerized or emulsion-polymerized in the presence of the fine colored polymer particles in a later step. The polymerization process becomes two steps, which increases the manufacturing cost.

Further, an attempt was made to produce a liquid crystal display device by using the above-mentioned colored polymer fine particles as the colored spacer in the latter invention. However, since the dispersibility of the pigment in the colored polymer fine particles was insufficient, the liquid crystal It was not possible to satisfactorily prevent the display contrast of the display element from being lowered.

Incidentally, existing colored spacers made of various colored plastic fine particles have a low coloring density of fine particles, or uncolored fine particles are mixed with the colored fine particles, and in any case, the display contrast of the liquid crystal display device is deteriorated. Could not be satisfactorily prevented.

The present invention is intended to solve the above problems, and its purpose is to disperse a pigment uniformly in polymer fine particles and to give a dark color, which has excellent mechanical strength and solvent resistance. (The property that the pigment is not extracted by the organic solvent)
(EN) Provided are a colored polymer fine particle having and a method for producing the same.

Another object of the present invention is to provide a spacer for a liquid crystal display element capable of favorably preventing a decrease in display contrast of the liquid crystal display element, and a liquid crystal display element using the spacer for a liquid crystal display element. Especially.

[0013]

In order to achieve the above object, the colored polymer fine particles of the present invention contain 100 to 60% by weight of a compound having 3 or more ethylenically unsaturated groups and 2 ethylenically unsaturated groups. A pigment is uniformly dispersed inside polymer fine particles obtained by polymerizing 100 parts by weight of a monomer containing a compound having a saturated group in an amount of 0 to 40% by weight and 5 to 50 parts by weight of (meth) acrylonitrile. It is a thing.

The method for producing colored polymer fine particles of the present invention comprises 100 to 60% by weight of a compound having three or more ethylenically unsaturated groups and 0 to 40% by weight of a compound having two ethylenically unsaturated groups. % Of the monomer, 5 to 50 parts by weight of (meth) acrylonitrile, and the pigment are mixed and suspended in an aqueous medium in the form of fine particles to carry out polymerization.

The spacer for a liquid crystal display device of the present invention comprises
The colored polymer microparticles described above or the colored polymer microparticles obtained by the above production method are used.

The liquid crystal display element of the present invention is obtained by using the above-mentioned spacer for a liquid crystal display element.

Examples of the compound having three or more ethylenically unsaturated groups used in the present invention include tetramethylolmethane tetra (meth) acrylate, tetramethylolmethane tri (meth) acrylate, trimethylolpropane tetra (meth) acrylate, and Pentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, glycerol tri (meth) acrylate, triallyl (iso) cyanurate,
Triallyl trimellitate and the like can be mentioned.

The compound having two ethylenically unsaturated groups used in the present invention is divinylbenzene,
1,4-divinyloxybutane, divinyl sulfone, diallyl phthalate, diallyl acrylamide, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, glycerol di (Meth) acrylate etc. are mentioned.

In the present invention, 100 to 60% by weight, preferably 90 to 70% by weight, of the above-mentioned compound having three or more ethylenically unsaturated groups, and compound 0 having two ethylenically unsaturated groups. -40% by weight, preferably 1
A monomer composed of 0 to 30% by weight is used.

When the content of the compound having three or more ethylenically unsaturated groups is less than 60% by weight, the cross-linking structure of the polymer is reduced, and the resulting colored polymer fine particles have poor mechanical strength and solvent resistance. On the other hand, when the amount of the compound having three or more ethylenically unsaturated groups increases, its polymerizability tends to decrease, and in order to improve this and adjust the degree of crosslinking of the polymer, two ethylene groups are used. The compound having a polyunsaturated group may be used in the range of 40% by weight or less.

Further, the type of the above-mentioned monomer and the amount thereof used are extremely important. If the ratio is deviated from this ratio, the pigment will be contained in the monomer even if an appropriate amount of (meth) acrylonitrile described later is used. It becomes difficult to disperse it uniformly.

The (meth) acrylonitrile is used in an amount of 5 to 50 parts by weight, preferably 10 to 40 parts by weight, based on 100 parts by weight of the above monomers. When the amount of the (meth) acrylonitrile used is less than 5 parts by weight, the dispersibility of the pigment in the monomer is lowered. On the contrary, when the amount of the (meth) acrylonitrile used exceeds 50 parts by weight, the ethylenically unsaturated group The amount of the monomer having a is relatively small, and the mechanical strength of the obtained colored polymer fine particles is lowered.

The pigment used in the present invention may be a commercially available ordinary organic pigment or inorganic pigment, and these pigments may be used alone or in admixture of two or more. . The average particle size of the pigment is preferably 1 micron or less, more preferably 0.05 to 0.5 μm.

As the organic pigment, quinacridone red,
Para Red, Chlorinated Para, Litol Rubin, Pigment Scar Red, Mader Lake, Alizarin Maroon, Helio Bordeaux, Thioindigo, Toluidine Maroon, Carbazole Dioxazine Violet, Red Lake C, Pyrazolone Red, Naphthol Red, Anthraquinone Red, Isoindolinone Red, Anthraquinone Yellow. , Benzidine yellow, hansa yellow, benzidine yellow toluidine, benzidine orange, disazo red, dianisidine orange, pyranthrone orange, GR perinone orange, isoindolinone yellow, flavanthrone yellow, anthrapyrimidine yellow, nickel azo yellow, phthalocyanine blue,
Examples include phthalocyanine green, pigment green B, indanthrone blue, and aniline black.

As the inorganic pigment, 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. Examples include blue, chrome green, emerald green, cobalt green, carbon black, and the like.

The amount of these pigments used is generally 1 based on the total amount of the above-mentioned monomer and (meth) acrylonitrile.
-50% by weight is preferable, and 3-30% by weight is more preferable. When the amount of the pigment used is less than 1% by weight, it is difficult to color the polymer fine particles in a dark color.
If it exceeds 0% by weight, the mechanical strength of the polymer fine particles decreases.

The following method is suitable as a specific method for producing the colored polymer fine particles of the present invention.

First, an appropriate amount of a monomer comprising a compound having the above-mentioned specific ethylenically unsaturated group, (meth) acrylonitrile and a pigment are mixed, and the pigment is mixed with the above-mentioned monomer (meth).
Disperse evenly in acrylonitrile. A ball mill, a bead mill, a sand mill, an attritor, a sand grinder, a nanomizer, or the like is used for mixing and dispersing the pigment. In this case, if necessary, for example, a known pigment dispersant such as Disparlon (trade name) manufactured by Kusumoto Kasei is used.

Next, a mixed liquid of the above-mentioned monomer, (meth) acrylonitrile and pigment is suspended in an aqueous medium in the form of fine particles. Water is generally used as the aqueous medium. Then, in this aqueous medium, an appropriate amount of a water-soluble suspension stabilizer is usually dissolved or a slightly water-soluble suspension stabilizer is dispersed and used.

As the water-soluble suspension stabilizer, polyvinyl alcohol, polyacrylic acid, polymethacrylic acid, gelatin, methyl cellulose, polymethacrylamide, polyethylene glycol, polyethylene oxide monostearate, sorbitan tetraoleate, glycerin monooleate. Water-soluble organic compounds such as dodecylbenzenesulfonic acid are used.

Further, as a sparingly water-soluble suspension stabilizer, barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, magnesium carbonate, calcium phosphate, magnesium phosphate colloid (mixture of sodium diphosphate and sodium chloride), colloidal A poorly water-soluble inorganic compound such as silica or aluminum oxide is used.

For suspending a mixture of the above-mentioned monomer, (meth) acrylonitrile and pigment in the form of fine particles in an aqueous medium, for example, the total amount of the monomer and (meth) acrylonitrile in the above mixed solution is added. 200 to 1000 parts by weight of an aqueous medium is mixed with 100 parts by weight, and the mixture is stirred with a stirring blade. By changing the stirring speed of the stirring blade and the viscosity of the aqueous medium, the particle size of the polymerizable monomer suspension particles and the particle size distribution can be adjusted. The average particle size of the suspended particles is generally adjusted to the range of 0.1 to 300 μm.

In order to carry out suspension polymerization of the (meth) acrylonitrile and the particulate monomer in which the pigment is dispersed,
The radical polymerization initiator is added to the above suspension in advance, or is added immediately before heating, and the radical polymerization initiator is decomposed by heating this to polymerize the monomer and (meth) acrylonitrile. Let

As the radical polymerization initiator, a usual oil-soluble radical polymerization initiator composed of an azonitrile compound or an organic peroxide is used. The polymerization initiator consisting of azonitrile compounds, 2,2 ^'- azobisisobutyronitrile, ^2,2' - azobis-2,4 ^'- dimethyl valeronitrile, ^2,2' - azobis - methylbutyronitrile , 2,2 ^'- azobis - the like methyl f script nitrile.

Examples of the radical polymerization initiator composed of an organic peroxide include acetyl peroxide, decanoyl peroxide, lauroyl peroxide, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and peroxide. Diisopropyl carbonate, di-2-ethylhexyl peroxide dicarbonate, acetylcyclohexylsulfonyl peroxide, t-butyl perisobutyrate, t-butyl perbivalate, t-butyl per-2-ethylhexanoate, di-t-butyl peroxide, Examples thereof include t-butyl cumyl peroxide and dicumyl peroxide.

These radical polymerization initiators are generally used in the range of 0.5 to 15 parts by weight based on 100 parts by weight of the total amount of the monomer and (meth) acrylonitrile. When the amount of the initiator is less than 0.5 part by weight, the polymerization rate is remarkably reduced,
It is not necessary to use more than 15 parts by weight of initiator. The polymerization temperature varies depending on the type of radical polymerization initiator used, but is generally about 40 to 150 ° C. The polymerization time is generally about 30 minutes to 10 hours.

In this way, colored polymer fine particles are produced. The colored polymer fine particles are separated by means such as filtration or centrifugation, washed with water or the like, and then dried by heating or reduced pressure to obtain colored polymer fine particles. It is considered a product. The colored polymer fine particles generally have an average particle diameter of about 0.1 to 300 μm, and the pigment is uniformly dispersed inside the polymer fine particles.

The colored polymer fine particles have excellent solvent resistance (the property that the pigment is not extracted by the organic solvent) and are usually used as they are, but if they are surface-treated with a silane coupling agent in advance. The solvent resistance can be further improved.

As the silane coupling agent used for this purpose, γ-aminopropyltrimethoxysilane, N
-Β- (aminoethyl) -γ-aminopropyltrimethoxysilane, 3- [N-allyl-N- (2-aminoethyl)] aminopropyltrimethoxysilane, 3- [N-
Amino-based silane coupling such as allyl-N-glycidyl) aminopropyltriethoxysilane, 3- [N-allyl-N-methacryl) aminopropyltrimethoxysilane, 3- [N, N-diglycidyl) aminopropyltrimethoxysilane Agents are preferred.

Further, N, N-bis [3- (methyldimethoxysilyl) propyl] amine, N, N-bis [3-
(Trimethoxysilyl) propyl] amine, N, N-bis [3- (methyldimethoxysilyl) propyl] ethylenediamine, N, N-bis [3- (trimethoxysilyl) propyl] ethylenediamine, N-glycidyl-
Amide-based silane coupling agents such as N, N-bis [3- (methyldimethoxysilyl) propyl] amine and N-glycidyl-N, N-bis [3- (trimethoxysilyl) propyl] amine are also suitable.

In addition, vinyl-based silane coupling agents such as vinyltriethoxysilane and vinyl-tris (2-methoxyethoxy) silane, methacrylic-based silane coupling agents such as γ-methacryloxypropyltrimethoxysilane, γ-glycid Glycidyl-based silane coupling agents such as xypropyltrimethoxysilane and mercapto-based silane coupling agents such as γ-mercaptopropyltrimethoxysilane are also used.

The colored polymer fine particles thus obtained are
It is used for various purposes such as a labeling material, a carrier for a diagnostic reagent, and a spacer for a liquid crystal display element, and is particularly suitable as a spacer for a liquid crystal display element.

To prepare a liquid crystal display device using the above-mentioned colored polymer fine particles as a spacer for a liquid crystal display device,
For example, the following method is adopted.

First, two transparent substrates with electrodes are prepared. Then, a sealing material made of a light or thermosetting adhesive in which a peripheral spacer is dispersed is applied to the peripheral portion of one transparent substrate in a frame shape, leaving the liquid crystal injection port. On the other surface of the other transparent substrate, an aqueous dispersion of the colored polymer fine particles whose particle size has been adjusted by classification is sprayed as a spacer for a liquid crystal display device and dried.

After that, one of the transparent substrates is placed on the other transparent substrate, and they are opposed to each other with a certain gap therebetween through the sealant and the spacer for the liquid crystal display device, and the peripheral sealant is exposed to light or heat. And cured to form a cell.

Next, after injecting liquid crystal into the cell through the liquid crystal injection port, the liquid crystal injection port is closed with a light or thermosetting liquid crystal injection port sealant, and the sealant is cured by light or heat. The liquid crystal injection port is sealed by the above to produce a liquid crystal display element.
In the obtained liquid crystal display element, the liquid crystal display element spacers are scattered over the entire surface of the substrate in contact with the liquid crystal in the cell gap.

The liquid crystal is generally a nematic liquid crystal,
In particular, nematic liquid crystals having a positive dielectric anisotropy are used, but cholesteric liquid crystals and smectic liquid crystals can also be used.

[0048]

As in the present invention, a unit amount consisting of 100 to 60% by weight of a compound having three or more ethylenically unsaturated groups and 0 to 40% by weight of a compound having two ethylenically unsaturated groups in advance. 100 parts by weight of the body, 5 to 50 parts by weight of (meth) acrylonitrile, and the pigment are uniformly mixed,
When suspended in an aqueous medium in the form of fine particles, (meth)
Since acrylonitrile has a very strong electron-withdrawing force due to the cyano group, it has a high affinity with the surface of pigment particles, and (meth)
It is considered that acrylonitrile collects near the surface of the pigment particles. As a result, it is assumed that the intermolecular force between the pigment particles is weakened, the pigment particles hardly agglomerate, and the pigment is uniformly dispersed in the fine particle droplets of the monomer.

When suspension polymerization is carried out in a state where the pigment is uniformly dispersed in the fine particle droplets of the monomer, the (meth) acrylonitrile existing near the surface of the pigment particle is copolymerized with the monomer. To form a copolymer and coat the surface of the pigment particles. In this way, the aggregation of pigment particles is reliably prevented,
Colored polymer fine particles in which pigment particles are uniformly dispersed inside the polymer fine particles are obtained.

When the pigment particles are uniformly dispersed in the polymer fine particles as described above, the mechanical strength is increased and a uniform and dark color is obtained as compared with the polymer fine particles in which the pigment particles are dispersed in an aggregated state. Will be colored.

Moreover, since the monomer is composed of a compound having a specific ethylenically unsaturated group as described above, the fine polymer particles obtained by the polymerization of this monomer have an appropriate crosslinked structure, It is presumed that the crosslinked structure and the molecular structure of the (meth) acrylonitrile-based copolymer are combined to improve the mechanical strength and solvent resistance (the property that the pigment is not extracted by the organic solvent) of the colored polymer particles.

In particular, when the colored polymer fine particles as described above are used as a spacer for a liquid crystal display device, the spacer for a liquid crystal display device is excellent in mechanical strength and solvent resistance and is uniformly and deeply colored. The visible light transmittance can be made almost zero, and as a result, when displaying with this liquid crystal display element, the spacers for the liquid crystal display element in the liquid crystal layer are not visually recognized as white dots in the dark part, It is possible to prevent a decrease in display contrast.

[0053]

EXAMPLES Examples and comparative examples of the present invention will be shown below. Example 1 (1) Production of colored polymer fine particles 85.5 g of tetramethylolmethane triacrylate, 28.5 g of divinylbenzene, and acrylonitrile 36.
0 g was evenly mixed, 14.5 g of aniline black was added as a pigment, and the pigment was uniformly dispersed using a bead mill for 48 hours.

2.0 g of benzoyl peroxide was uniformly mixed with the monomer mixture of the pigment dispersion, and this was mixed at a concentration of 3% by weight.
Was poured into 850 g of the polyvinyl alcohol aqueous solution and thoroughly stirred, and this was suspended in the form of fine particles having a particle size of about 3 to 10 μm with a homogenizer.

This suspension was transferred to a 2 liter separable flask equipped with a thermometer, a stirrer and a reflux condenser,
The mixture was heated to 85 ° C. with stirring in a nitrogen atmosphere for 7 hours to carry out a polymerization reaction, and further heated at 90 ° C. for 3 hours to carry out a polymerization reaction.

Thereafter, the polymerization reaction liquid was cooled, and the produced colored polymer fine particles were filtered, sufficiently washed with water and dried to obtain 145 g of colored polymer fine particles having a particle diameter of about 3 to 10 μm. The colored polymer particles were classified to obtain colored polymer particles having a desired particle size distribution.

(2) Performance Evaluation / Coloring State of Colored Polymer Fine Particles When the color density of the above colored polymer fine particles was visually observed, it was black and dark and uniformly colored. Further, when the surface and the cut surface of the colored polymer particles were observed by a scanning electron microscope, it was confirmed that the pigment was uniformly dispersed inside the polymer particles.

Mechanical strength The colored polymer fine particles (average particle size 6.67 μm, standard deviation 0.35 μm) whose particle size was adjusted by classification using a micro compression tester (PCT-20 manufactured by Shimadzu Corporation) Was measured for mechanical strength. This mechanical strength is 10% compressive deformation strength (K ₁₀ value) (kgf / mm ² ) in one fine particle sample.
Also, the recovery rate (%) of the compressive deformation during gradual loading was evaluated.

[0059] Here, the strength of 10% compression deformation of particle samples (K _{10 ^{value), K 10 = 3/2 1/2}} · F · S -3/2 · R
It is expressed by ^-1/2 , F is the compressive load (kgf), S is the displacement (mm) during 10% compressive deformation, and R is the particle size (mm) of the fine particle sample. As a result, the K ₁₀ value was 480 ± 20 (kgf / mm ² ), and the recovery rate was 6
At 4.4%, the mechanical strength is excellent. Solvent resistance: 1 g of the colored polymer fine particles was added to 50 ml of an ethanol solvent and an acetone solvent, allowed to stand at 20 ° C. for 7 days and then filtered, and the maximum absorption and transmittance of the filtrate was measured in the visible light region. As a result, the transmittance of the ethanol solvent was 98.6.
%, And 97.5% with an acetone solvent, there is almost no pigment extraction (decolorization) with an organic solvent, and solvent resistance is excellent.

(3) Fabrication of Liquid Crystal Display Element As shown in a sectional view of FIG. 1, a transparent electrode (ITO thin film) 2
A sealing material 5 made of an epoxy acrylate-based photo-curing adhesive in which milled glass fibers with a diameter of 6.48 μm (peripheral spacer) are dispersed around the periphery of one transparent glass substrate 1 on which the Screen printing is carried out in the shape of a frame while leaving the number 6.

Further, on the entire surface of the other transparent glass substrate 1 on which the transparent electrode (ITO thin film) 2 is vapor-deposited, the colored polymer fine particles (average particle size 6 An aqueous dispersion having a density of 0.67 μm and a standard deviation of 0.35 μm) was sprayed at about 100 particles / mm ² and dried.

After that, the one transparent glass substrate 1 is placed on the other transparent glass substrate 1, and they are opposed to each other with a certain gap therebetween via the sealing material 5 and the spacer A for liquid crystal display element, and the mercury lamp is opposed to this. By irradiating ultraviolet rays,
The sealing material 5 was photo-cured to form a cell. In addition, 3 is an alignment film and 4 is a polarizing plate.

After injecting the nematic liquid crystal 8 into the cell through the liquid crystal injection port 6, the liquid crystal injection port 6 is closed with a photocurable liquid crystal injection port sealant 7, and the above-mentioned sealing is performed by irradiating ultraviolet rays with a mercury lamp. The agent 7 was cured and the liquid crystal injection port 6 was sealed to produce a liquid crystal display element 9.

(4) Evaluation of Display Quality of Liquid Crystal Display Element Ten liquid crystal display elements were produced under the same conditions as above, and the gap between the substrates of each liquid crystal display element was measured. The gap was 6.35 ± 0. It was 05 μm.

When a negative type display showing a dark level was applied without applying a voltage, the spacers in the liquid crystal layer were not visually recognized as white spots in the dark part, and the display contrast of the liquid crystal display element was good. The above results are summarized in Table 1.

Examples 2 to 6 and Comparative Examples 1 to 3 In Example 1, compounds having 3 or more ethylenically unsaturated groups, compounds having 2 ethylenically unsaturated groups, (meth) acrylonitrile and pigment Was changed as shown in Table 1 and Table 2. Other than that was performed like Example 1. The results are summarized in Tables 1 and 2.

[0067]

[Table 1]

[0068]

[Table 2]

[0069]

INDUSTRIAL APPLICABILITY As described above, the colored polymer fine particles of the present invention are compound 1 having three or more ethylenically unsaturated groups.
Polymer fine particles obtained by polymerizing 100 parts by weight of a monomer composed of 0 to 60% by weight and 0 to 40% by weight of a compound having two ethylenically unsaturated groups, and 5 to 50 parts by weight of (meth) acrylonitrile. The pigment is uniformly dispersed inside the pigment, whereby it is colored darkly and has excellent mechanical strength and solvent resistance (the property that the pigment is not extracted by the organic solvent).

The method for producing fine colored polymer particles according to the present invention comprises 100 to 60% by weight of a compound having 3 or more ethylenically unsaturated groups and 0 to 40% by weight of a compound having 2 ethylenically unsaturated groups. % Of the monomer, 5 to 50 parts by weight of (meth) acrylonitrile, and the pigment are uniformly mixed and suspended in an aqueous medium in the form of fine particles to carry out polymerization. By this, it is possible to obtain colored polymer fine particles in which the pigment is uniformly dispersed and colored in a dark color, and which has excellent mechanical strength and solvent resistance (the property that the pigment is not extracted by the organic solvent).

Moreover, according to the method for producing colored polymer fine particles of the present invention, the production of the polymer fine particles and the uniform dispersion of the pigment inside the polymer fine particles are carried out at once in one polymerization step. The process is simplified and the colored polymer fine particles can be manufactured at low cost.

Therefore, the colored polymer fine particles of the present invention can be suitably used as a labeling material, a carrier for a diagnostic reagent, a spacer for a liquid crystal display device and the like. In particular, when used as a spacer for a liquid crystal display element, when the obtained liquid crystal display element is displayed, the spacer in the liquid crystal layer is not visually recognized as a white dot in the dark part, and the deterioration of the display contrast of the liquid crystal display element is prevented. The advantage is that

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing an example of a liquid crystal display element of the present invention.

[Explanation of symbols]

 1 Transparent Glass Substrate 2 Transparent Electrode 3 Alignment Film 4 Polarizing Plate 5 Sealing Material 6 Liquid Crystal Injection Port 7 Liquid Crystal Injection Port Sealant 8 Liquid Crystal 9 Liquid Crystal Display Element A Spacer for Liquid Crystal Display Element

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location G02F 1/1339 500 8507-2K

Claims (4)

[Claims] 1. A monomer 100 comprising 100 to 60% by weight of a compound having 3 or more ethylenically unsaturated groups and 0 to 40% by weight of a compound having 2 ethylenically unsaturated groups.
Colored polymer fine particles, wherein the pigment is uniformly dispersed inside the polymer fine particles obtained by polymerizing 5 parts by weight of (meth) acrylonitrile and 5 parts by weight of (meth) acrylonitrile. 2. A monomer 100 comprising 100 to 60% by weight of a compound having three or more ethylenically unsaturated groups and 0 to 40% by weight of a compound having two ethylenically unsaturated groups.
Parts by weight, 5 to 50 parts by weight of (meth) acrylonitrile and a pigment are uniformly mixed, and the mixture is suspended in an aqueous medium in the form of fine particles to carry out polymerization, and a method for producing fine particles of a colored polymer. . 3. A spacer for a liquid crystal display device, comprising the colored polymer fine particles according to claim 1 or the colored polymer fine particles obtained by the production method according to claim 2. 4. A liquid crystal display device comprising two transparent substrates with electrodes arranged so that the electrodes face each other, and liquid crystal is sealed in the gap between the substrates, wherein the entire surface of the substrate in contact with the liquid crystal in the gap is covered. A liquid crystal display device comprising the liquid crystal display device spacers as described above.