JPH0950036A - Liquid crystal display spacer and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to prohibit the orientation of liquid crystal molecules on spacer surfaces and to prevent the abnormal orientation around and between the spacers by forming the surfaces of the spacers to a rough shape. SOLUTION: This liquid crystal display device is composed of a pair of substrates 8, 10, nematic liquid crystals 11 enclosed between these substrates 8 and 10, a sealing member 1 packed around the substrates 8, 10 and polarization sheets 12, 13 formed on the substrates 8, 10 to cover their surfaces as constituting materials. The spacers 9 are arranged between the substrates 8 and 10 in order to maintain the specified gap between a pair of the substrates 8 and 10. In such a case, the area ratio (Sa /S0 ) of the surface area (S0 ) calculated on assumption that the surfaces of the polymer particle are smooth and the actually measured surface area (Sa ) in the particles used as the spacers 9 specified to 1.2 to 8. The polymer particulates are obtd. by polymerizing polymerizable monomers or a mixture composed of the polymerizable monomers in the presence of a polymerizable initiator by a method, such as suspension polynm. or seed polymn.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display spacer and a liquid crystal display device. More specifically, the present invention relates to a liquid crystal display spacer and a liquid crystal display device that prevent abnormal alignment of liquid crystal around the spacers and between the spacers in the initial state and when a high voltage is applied, thereby enabling uniform display.

[0002]

2. Description of the Related Art As shown in FIG. 1, a conventional TN (twisted nematic) mode liquid crystal display device using a spacer includes a pair of substrates 8 and 10, and the substrates 8 and 1.
Nematic liquid crystal 11 enclosed between 0 and substrates 8 and 1
The sealing member 1 filled around 0 and the polarizing sheets 12 and 13 coated on the surfaces of the substrates 8 and 10 are used as constituent materials,
In order to keep the gap between the pair of substrates 8 and 10 constant, a spacer 9 is arranged between the substrates 8 and 10.

The substrates 8 and 10 have a pattern of transparent electrodes 3 and 6 made of an ITO film or the like formed on one surface of glass transparent substrates 2 and 5, and a polyimide film or the like on the other surface of the transparent substrates 2 and 5. The alignment control films 4 and 7 are covered. The orientation control films 4 and 7 are subjected to orientation control processing by rubbing.

As the spacer 9, an organic or inorganic material is used. Examples of the inorganic material spacer include those containing aluminum oxide, silicon dioxide and the like (for example, JP-A-63-73225 and JP-A-1-59).
974, etc.). In addition, the spacer made of an organic material is easy to follow the change in thickness due to thermal expansion and contraction of the liquid crystal layer,
Further, it is characterized in that the spacer migration in the cell is small, and polystyrene-based or benzoguanamine-based polymers are mainly used (for example, JP-A-60-200).
No. 228, JP-A-1-293316, etc.).

In the spacer used in such a liquid crystal display device, an abnormality of the liquid crystal around the liquid crystal spacer is generated immediately after the cell of the liquid crystal display device made by using these is made (hereinafter referred to as an initial state) and when a high voltage is applied. There is a problem that orientation occurs. In particular, in a display device using STN (Super Twisted Nematic) liquid crystal, there is a problem that the tendency becomes remarkable and a uniform image cannot be held.

The cause of this abnormal alignment is that the liquid crystal molecules are aligned around the spacer, and it is estimated that the size of the abnormal alignment depends on the degree of alignment of the liquid crystal molecules. In order to solve these problems, studies are being conducted to change the dielectric constant of the spacer (JP-A-6-67182) and the spacer surface composition (JP-A-6-118421). However, as a spacer used in these display devices, a spacer having a smooth surface has been conventionally used, so that it is not possible to sufficiently prevent abnormal alignment of liquid crystal molecules.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal display in which abnormal alignment of liquid crystal does not occur around the spacer for liquid crystal display and a uniform and good image can be obtained. An object of the present invention is to provide a spacer for liquid crystal display capable of manufacturing a device and a liquid crystal display device using the spacer.

[0008]

The spacer for liquid crystal display according to the invention of claim 1 (hereinafter referred to as the first invention) is calculated as a polymer fine particle used for the spacer, assuming that the surface of the fine particle is smooth. The area ratio (S _a / S ₀ ) between the measured surface area (S ₀ ) and the actually measured surface area (S _a ) is 1.2 to 8.

The fine polymer particles used as the spacer for liquid crystal display in the first invention are prepared by a method such as suspension polymerization or seed polymerization of a polymerizable monomer or a mixture of polymerizable monomers in the presence of a polymerization initiator. It can be obtained by polymerizing.

As the above-mentioned polymerizable monomer, an ethylenically unsaturated monomer or the like is preferably used, and examples thereof include styrene and α.
-Styrene derivatives such as methylstyrene, p-methylstyrene, p-chlorostyrene and chloromethylstyrene; vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; unsaturated nitriles such as acrylonitrile;
Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, (meth) acrylic acid 2
-(Meth) acrylic acid ester derivatives such as ethylhexyl, stearyl (meth) acrylate, ethylene glycol (meth) acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) acrylate, cyclohexyl (meth) acrylate; butadiene, Examples thereof include polymers such as conjugated dienes such as isoprene. These may be used alone or in combination of two or more.

In particular, from the viewpoint of improving the strength of the spacer, it is preferable to use the ethylenically unsaturated monomer and a crosslinkable monomer having two or more ethylenically unsaturated groups in combination.

Examples of the crosslinkable monomer having two or more ethylenically unsaturated groups include divinylbenzene, ethylene oxide di (meth) acrylate, tetraethylene oxide di (meth) acrylate, 1,6-hexanediol acrylate, Neopentyl glycol diacrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane triacrylate, tetramethylolpropane tetra (meth) acrylate,
Examples thereof include diallyl phthalate and its isomers, triallyl isocyanurate and its derivatives. These may be used alone or in combination of two or more.

When the ethylenically unsaturated monomer and the crosslinkable monomer are used in combination, the ratio of the crosslinkable monomer is such that the total amount of the monomer (polymerizable monomer + crosslinkable monomer) is 10 to 95% by weight is preferable.

Examples of the polymerization initiator used in the first invention include benzoyl peroxide, lauroyl peroxide, orthochlorobenzoyl peroxide, orthomethoxybenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, and t. -Butylperoxy-2-ethylhexanoate, organic peroxides such as di-t-butylperoxide; azobisisobutyronitrile, azobiscyclohexacarbonitrile, azobis (2,4-dimethylbereronitrile) ) And other azo compounds.

In the polymer fine particles used as the spacer for liquid crystal display, the area ratio (S) between the surface area (S ₀ ) calculated as a smooth surface of the fine particles and the actually measured surface area (S _a ). _a / S ₀ ) is limited to 1.2 to 8, preferably 1.2 to 4. Area ratio (S _a /
When S ₀ ) is smaller than 1.2, abnormal alignment of liquid crystal on the surface of the spacer is likely to occur, and when it is larger than 8, the strength of the spacer is lowered, so that it cannot be used as a spacer for liquid crystal display.

As a method for synthesizing the above-mentioned polymer fine particles having a rough surface by suspension polymerization and seed polymerization, for example, the method disclosed in Japanese Patent Publication No. 1-23945 can be cited.

The surface area of the polymer fine particles can be measured using a multipoint specific surface area measuring apparatus using a gas adsorption method. The actual measurement is performed using a high-precision specific surface area measuring device (“BELSORP28SA” manufactured by Bell Japan Ltd.)
_Two gases were used.

The average particle size of the polymer particles used as the spacer for the liquid crystal display is preferably 1 to 15 μm.

If the particle size distribution Cv value [(standard deviation / average particle size) × 100] of the above-mentioned polymer fine particles becomes large, the gap distance of the liquid crystal display device varies, which causes deterioration of the image. Is preferred.

As for the mechanical strength of the polymer fine particles, the 10% K value is preferably 250 to 700 kgf / mm ² , and the recovery rate after compression deformation is preferably 30 to 80%.

The K value referred to here is the table 6-5031.
According to No. 80 publication, a fine compression tester (“PCT-200” manufactured by Shimadzu Corporation) was used to apply the above polymer fine particles to a smooth end face of a diamond cylinder having a diameter of 50 mμ and a compression rate of 0.27 g / It is a value calculated from the following formula (1) after being compressed until the maximum test load is 10 g in seconds. K = (3 / √2) × F × S ^−3/2 × R ^−1/2 (1) [where F, S, and R are at 10% compression deformation of polymer particles] The load value (kg), the compression displacement (mm), and the radius (mm) of the polymer particles are shown below.

The recovery rate after compressive deformation is a special table.
In accordance with Japanese Unexamined Patent Publication No. 6-503180, the above micro compression test
Using a tester, load polymer particles at a rate of 0.27 g / sec.
After adding weight and compressing to a load of 1g, reversely load 0.1g
Until the point where you want to start reducing the load
Displacement L to the point of reversal depending on the test method)
₁And the displacement L from the point of reversal to the point where the origin load value is taken₂To
Measure the ratio of both (L₂/ L₁) Is expressed as a percentage (%)
It is defined by the value.

Next, the invention according to claim 2 (hereinafter referred to as the second invention) will be described. The spacer for liquid crystal display of the second invention is characterized in that the polymer fine particles used in the first invention are formed of a fluorine-based polymer having a fluorine content of 2 to 40% by weight.

The fine polymer particles used in the second invention are formed of a fluoropolymer. The above-mentioned fluorine-based polymer is a method in which a polymer synthesized by suspension polymerization or seed polymerization in the first invention is used as seed particles, and a fluorine-based monomer is further added for polymerization, or a configuration including a fluorine-based monomer from the beginning. Examples include a method of adding components and polymerizing.

As the above-mentioned fluorine-based monomer, trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, pentafluoropropyl (meth) acrylate, octafluoroamyl (meth)
(Meth) acrylic acid ester derivatives such as acrylate, heptadecafluorodecyl (meth) acrylate, perfluorobutylethyl (meth) acrylate; vinylidene fluoride, trifluorochloroethylene, trifluoroethylene, tetrafluoroethylene, trifluoro Examples thereof include fluorinated compounds such as propylene and hexafluoropropylene.

When the fluorine content in the above-mentioned fluorine-containing polymer is small, the effect of preventing aggregation as a spacer is not sufficient, and when it is large, the adhesiveness to the substrate (here, the adhesiveness means that an air gun of 2 kg / cm ³ is used). It is limited to 2 to 40% by weight, preferably 4 to 30% by weight, since the spacer remains on the substrate when sprayed).

The fluorine content in the above-mentioned fluorine-containing polymer can be determined by subjecting the solution obtained by the flask combustion method to ion chromatography (DIONEX 2000i) to quantify F ⁻ ion.

In the polymer fine particles of the second invention, the area ratio (S _a / S) between the surface area (S ₀ ) calculated assuming that the surface of the fine particles is smooth and the surface area (S _a ) actually measured.
₀ ) is limited to 1.2 to 8, and preferably 1.2 to 4 for the same reason as in the first invention.

Next, the invention according to claim 3 (hereinafter referred to as the third invention) will be described. In the liquid crystal display device of the third invention, two glass substrates on which an alignment film and a transparent electrode are arranged are opposed to each other via the liquid crystal display spacer of the first invention or the second invention, and a liquid crystal is interposed between the glass substrates. It is characterized by being enclosed.

As the above liquid crystal display device, for example, FIG.
The ones shown in are listed.

[0031]

The liquid crystal display spacer of the present invention makes it possible to prevent the alignment of liquid crystal molecules on the spacer surface and prevent abnormal alignment around and between the spacers by roughening the surface. Further, it is considered that the spacers do not aggregate with each other in the spacer manufacturing step and have good sprayability on the substrate.

[0032]

Embodiments of the present invention will be described below. (Example 1) [Production of seed particles (A)] 1.2 parts by weight of polyvinylpyrrolidone (weight average molecular weight 30,000), 0.57 parts by weight of aerosol OT (manufactured by Wako Pure Chemical Industries: anionic surfactant) and azobis While stirring a solution prepared by dissolving 1.43 parts by weight of isobutyronitrile in 83.8 parts by weight of ethanol, 20 parts by weight of styrene was added under stirring in a nitrogen stream, and the temperature was raised to 70 ° C. to carry out a polymerization reaction for 24 hours. Then, seed particles (A) were obtained. The seed particles (A) have a weight average molecular weight (Mw).
The average particle size was 9,000 and the average particle size was 3.2 μm.

[Synthesis of Spacer] To 5 parts by weight of the seed particles (A), 200 parts by weight of ion-exchanged water and 0.13 part by weight of sodium lauryl sulfate were added and uniformly dispersed, and then 31.5 parts by weight of divinylbenzene and Mix 3 parts by weight of benzoyl peroxide and disperse with a homogenizer.
Finely emulsified to 0.2 μm. The obtained emulsion was added to the dispersion liquid of seed particles (A), and stirred at 25 ° C. at a rotation speed of 200 rpm for 3 hours to be absorbed by the seed particles (A).
Polyvinylpyrrolidone (weight average molecular weight 3
After adding 100 parts by weight of a 3% by weight aqueous solution of
1 at 70 ° C under nitrogen stream while stirring at rpm.
Polymerization was performed for 2 hours. Polymer particles were taken out from the obtained dispersion liquid by centrifugation, and the dispersant was completely washed with ion-exchanged water and methanol heated to 80 ° C. or higher and then dried to obtain a spacer for liquid crystal display.

Average particle size, Cv value, 1 of the above spacer
The 0% K value, the recovery rate after compression deformation and the surface area ratio were measured by the following methods, and the results are shown in Table 1. (A) Average particle size Measured using a laser diffraction / scattering particle size analyzer "9220 FRA" manufactured by Microtrac. (B) Cv value (particle size distribution) The Cv value was calculated from the particle size measurement result of (a). (C) 10% K value and recovery rate after compression deformation It was calculated from the result of measurement using a micro compression tester “PCT-200 type” manufactured by Shimadzu Corporation. (D) Surface area ratio High-precision specific surface area measuring device "BELSORP" manufactured by Bell Japan
28SA "was used and measured with CO ₂ gas.

[Evaluation of Liquid Crystal Display Device] Substrate size 50 (mm) × 50 using the spacer synthesized by the above method
(Mm) and a cell gap of 6.0 μm, an STN type liquid crystal display device was prepared, and cell evaluation was performed as follows. A cell display characteristic in the initial state was evaluated by applying a voltage of Ac3V to the liquid crystal display device, and then 400 Hz, 2
After applying a voltage of 0 to 50 V, a voltage of 3 V was further applied to evaluate the cell display characteristics in the voltage applied state. As a result, no abnormal orientation was observed around the spacer immediately after the cell was formed and after the charge was applied.

Example 2 Seed particles (B) were synthesized in the same manner as the seed particles (A) except that the addition amount of styrene was changed to 15 parts by weight. To the seed particles (B), 200 parts by weight of ion-exchanged water and 0.13 parts by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately
45.5 parts by weight of divinylbenzene, 19.5 parts by weight of n-butyl methacrylate and 3 parts by weight of benzoyl peroxide were mixed and dispersed by a homogenizer, and finely dispersed and emulsified to 0.2 μm to obtain an emulsion. The obtained emulsion was added to the dispersion liquid of the seed particles (B), and stirred at 25 ° C. at a rotation speed of 200 rpm for 3 hours to be absorbed by the seed particles (B). Next, after obtaining a spacer for liquid crystal display from the obtained dispersion liquid in the same manner as in Example 1, the same evaluation as in Example 1 was performed, and the results are shown in Table 1. Further, a liquid crystal display device was manufactured from the liquid crystal display spacer in the same manner as in Example 1 and evaluated in the same manner as in Example 1, but no abnormal alignment was observed around the spacer immediately after cell formation and after charge was applied. It was

Example 3 Seed particles (C) were synthesized in the same manner as the seed particles (A) except that the addition amount of styrene was changed to 10 parts by weight. To the seed particles (C), 200 parts by weight of ion-exchanged water and 0.13 parts by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately
Divinylbenzene (45.5 parts by weight), pentafluoropropyl methacrylate (19.5 parts by weight) and benzoyl peroxide (3 parts by weight) were mixed and dispersed by a homogenizer.
Finely emulsified to 2 μm to obtain an emulsion. The obtained emulsion is added to the dispersion liquid of seed particles (C), and the mixture is added at 25 ° C. for 200 r.
The mixture was stirred for 3 hours at a rotation speed of pm and absorbed by the seed particles (C). Then, after obtaining a spacer for liquid crystal display from the obtained dispersion liquid in the same manner as in Example 1, the same evaluation as in Example 1 was performed, and the results are shown in Table 1. Furthermore, a liquid crystal display device was manufactured in the same manner as in Example 1 using the liquid crystal display spacers, and then the same evaluation as in Example 1 was performed. However, abnormality was observed around the spacer both immediately after cell formation and after charge was applied. No orientation was observed.

Example 4 In a separable flask, 80 parts by weight of divinylbenzene, 20 parts by weight of styrene, 40 parts by weight of toluene, and 50% by weight of a 3% polyvinyl alcohol aqueous solution were used.
0 parts by weight and 15 parts by weight of benzoyl peroxide were stirred, heated to 80 ° C., and then polymerized for 24 hours. The polymer particles were taken out from the obtained dispersion by centrifugation and
After thoroughly washing the dispersant with ion-exchanged water and methanol heated to a temperature of not less than 0 ° C., a spacer for liquid crystal display was obtained by classification. Then, for the obtained liquid crystal display spacer,
The same evaluation as in Example 1 was performed, and the results are shown in Table 1. Further, a liquid crystal display device was manufactured in the same manner as in Example 1 using a spacer for liquid crystal display, and then the same evaluation as in Example 1 was carried out. Was not recognized.

Comparative Example 1 To the seed particles (B) obtained in Example 3, 200 parts by weight of ion-exchanged water and 0.13 parts by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately, 250 parts by weight of divinylbenzene and 3 parts by weight of benzoyl peroxide are mixed and dispersed by a homogenizer,
Finely emulsified to 0.2 μm to obtain an emulsion. The obtained emulsion is added to the dispersion liquid of seed particles (B), and the mixture is heated at 25 ° C. for 20
The seed particles (B) were absorbed by stirring at a rotation speed of 0 rpm for 3 hours. Then, after obtaining a spacer for liquid crystal display from the obtained dispersion liquid in the same manner as in Example 1, the same evaluation as in Example 1 was performed, and the results are shown in Table 1. further,
After a liquid crystal display device was manufactured in the same manner as in Example 1 using the spacers for liquid crystal display, the same evaluation as in Example 1 was carried out. As a result, abnormal orientation appeared in a part around the spacer from the initial state and the charge After application, 95% or more of the spacers and abnormal alignment occurred between the spacers.

The ratio (%) of abnormal orientation is shown by the ratio (percentage) of the total number of spacers and the number of spacers showing abnormal alignment.

Comparative Example 2 A spacer for liquid crystal display was obtained in the same manner as in Example 1 except that the particles (A) obtained in Example 1 were used and 5 parts by weight of divinylbenzene was used. The same evaluation as in Example 1 was performed, and the results are shown in Table 1. The recovery rate could not be measured because no recovery was observed. In addition, the spacer was cracked in the manufacturing process of the liquid crystal display device using the spacer, and the evaluation could not be performed.

Comparative Example 3 A spacer for liquid crystal display was obtained in the same manner as in Example 4 except that toluene was not used in the synthesis of the spacer, and then the same evaluation as in Example 1 was carried out. The results are shown in Table 1. Furthermore, using a liquid crystal display spacer in the same manner as in Example 1,
After manufacturing a liquid crystal display device, the same evaluation as in Example 1 was performed. As a result, abnormal alignment appeared in a part around the spacer from the initial state, and after application of charge, 95% or more of the abnormal alignment around the spacer and between the spacers. There has occurred.

[0043]

[Table 1]

(Example 5) Seed particles (A) of Example 1
To 5 parts by weight, 200 parts by weight of ion-exchanged water and 0.13 part by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately, 22.1 parts by weight of divinylbenzene, 9.5 parts by weight of pentafluoropropyl methacrylate and 3 parts by weight of benzoyl peroxide were mixed and dispersed with a homogenizer.
Finely emulsified to 0.2 μm to obtain an emulsion. The obtained emulsion was added to the dispersion liquid of seed particles (A), and the mixture was added at 25 ° C for 20
The seed particles (A) were absorbed by stirring at a rotation speed of 0 rpm for 3 hours. Then using the dispersion obtained, Example 1
After the liquid crystal display spacer was obtained in the same manner as described above, the same evaluation as in Example 1 was performed, and the results are shown in Table 2. Further, from the liquid crystal display spacer in the same manner as in Example 1,
After the liquid crystal display device was manufactured, the same evaluation as in Example 1 was performed, but no abnormal alignment was observed around the spacer immediately after the cell was manufactured and after the charge was applied. The spraying property was evaluated by a dry spraying method.

Example 6 Seed particles (B) of Example 2
To 5 parts by weight, 200 parts by weight of ion-exchanged water and 0.13 part by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately, 45.5 parts by weight of divinylbenzene, 19.5 parts by weight of trifluoroethyl methacrylate and 3 parts by weight of benzoyl peroxide were mixed and dispersed by a homogenizer,
Finely emulsified to 2 μm to obtain an emulsion. The obtained emulsion is added to the dispersion liquid of seed particles (B), and the mixture is added at 25 ° C. for 200 r.
The seed particles (B) were absorbed by stirring for 3 hours at a rotation speed of pm. Then, using the obtained dispersion liquid, a spacer for liquid crystal display was obtained in the same manner as in Example 1, and then the same evaluation as in Example 1 was carried out. The results are shown in Table 2. Further, a liquid crystal display device was manufactured from the spacer for liquid crystal display in the same manner as in Example 1, and then the same evaluation as in Example 1 was performed. However, abnormal alignment was observed around the spacer both immediately after cell formation and after charge was applied. I couldn't do it.

(Example 7) Seed particles (C) of Example 3
To 5 parts by weight, 200 parts by weight of ion-exchanged water and 0.13 part by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately, divinylbenzene 40 parts by weight, tetrafluoropropyl methacrylate 30 parts by weight and benzoyl peroxide 3
Mix parts by weight and disperse with a homogenizer.
m was finely dispersed and emulsified to obtain an emulsion. The obtained emulsion was added to the dispersion liquid of seed particles (C) and stirred at 25 ° C. at a rotation speed of 200 rpm for 3 hours to be absorbed by the seed particles (C).
Next, after using the obtained dispersion liquid in the same manner as in Example 1 to obtain a spacer for liquid crystal display, the same evaluation as in Example 1 was carried out, and the results are shown in Table 2. Further, a liquid crystal display device was manufactured from the spacer for liquid crystal display in the same manner as in Example 1, and then the same evaluation as in Example 1 was performed. However, abnormal alignment was observed around the spacer both immediately after cell formation and after charge was applied. I couldn't do it.

Example 8 In a separable flask, 80 parts by weight of divinylbenzene, 20 parts by weight of pentafluoropropyl methacrylate, 40 parts by weight of toluene, 500 parts by weight of a 3% by weight polyvinyl alcohol aqueous solution and 15 parts by weight of benzoyl peroxide were stirred. After heating to 80 ° C., polymerization was carried out for 24 hours. Polymer particles were taken out from the obtained dispersion by centrifugation, and the dispersant was thoroughly washed with ion-exchanged water and methanol heated to 80 ° C. or higher, and then classified to obtain a spacer for liquid crystal display. The obtained liquid crystal display spacer was evaluated in the same manner as in Example 1, and the results are shown in Table 2. Furthermore, after producing a liquid crystal display device from the liquid crystal display spacer in the same manner as in Example 1,
The same evaluation as in Example 1 was performed, but no abnormal orientation was observed around the spacer immediately after the cell was formed and after the charge was applied.

(Comparative Example 4) Seed particles (B) of Example 2
To 5 parts by weight, 200 parts by weight of ion-exchanged water and 0.13 part by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately, 250 parts by weight of divinylbenzene, 50 parts by weight of pentafluoropropyl methacrylate and 3 parts by weight of benzoyl peroxide were mixed and dispersed with a homogenizer to obtain 0.2
Finely emulsified to μm to obtain an emulsion. The obtained emulsion was added to the dispersion liquid of the seed particles (B) obtained in Example 2,
The mixture was stirred at 25 ° C. and a rotation speed of 200 rpm for 3 hours and absorbed by the seed particles (B). Next, after using the obtained dispersion liquid in the same manner as in Example 1 to obtain a spacer for liquid crystal display, the same evaluation as in Example 1 was carried out, and the results are shown in Table 2. Further, after manufacturing a liquid crystal display device from the liquid crystal display spacer in the same manner as in Example 1, the same evaluation as in Example 1 was performed. As a result, abnormal alignment appeared in a part around the spacer from the initial state, and charge was applied. After that, 95% or more of the abnormal orientation occurred around the spacers and between the spacers.

Comparative Example 5 To the seed particles (B) obtained in Example 2, 200 parts by weight of ion-exchanged water and 0.13 parts by weight of sodium lauryl sulfate were added and uniformly dispersed. Separately, 65 parts by weight of divinylbenzene and 3 parts by weight of benzoyl peroxide were mixed and dispersed with a homogenizer to give 0.2
Finely emulsified to μm to obtain an emulsion. The obtained emulsion is added to the dispersion liquid of the seed particles (B), and the temperature is 25 ° C. and 200 rp.
The seed particles (B) were absorbed by stirring for 3 hours at a rotation speed of m. Then, using the obtained dispersion liquid, a spacer for liquid crystal display was obtained in the same manner as in Example 1, and then the same evaluation as in Example 1 was carried out. The results are shown in Table 2. Further, a liquid crystal display device was produced from the liquid crystal display spacer in the same manner as in Example 1, and then the same evaluation as in Example 1 was performed.
Abnormal orientation was not observed around the spacer both immediately after cell formation and after charge was applied.

Comparative Example 6 A liquid crystal display spacer was obtained in the same manner as in Example 5 except that the amount of divinylbenzene used was changed to 5 parts by weight in the preparation of the emulsion, and then the same procedure as in Example 1 was performed. The evaluation was performed, and the results are shown in Table 2.
The recovery rate could not be measured because no recovery was observed. Further, an attempt was made to manufacture a liquid crystal display device from the liquid crystal display spacer in the same manner as in Example 1, but the spacer was cracked in the manufacturing process and could not be evaluated.

COMPARATIVE EXAMPLE 7 From 80 parts by weight of divinylbenzene, 60 parts by weight of n-butyl acrylate, 40 parts by weight of toluene, 500 parts by weight of a 3% aqueous solution of polyvinyl alcohol and 15 parts by weight of benzoyl peroxide, Example 4 was obtained.
Polymerization was carried out in the same manner as above to produce a spacer for liquid crystal display.
Then, after obtaining a spacer for liquid crystal display from the obtained dispersion liquid in the same manner as in Example 1, the same evaluation as in Example 1 was performed, and the results are shown in Table 2. Further, after manufacturing a liquid crystal display device from the liquid crystal display spacer in the same manner as in Example 1, the same evaluation as in Example 1 was performed. As a result, abnormal alignment appeared in a part around the spacer from the initial state, and charge was applied. After that, 95% or more of the abnormal orientation occurred around the spacers and between the spacers.

[0052]

[Table 2]

[0053]

The liquid crystal display spacer of the present invention has the above-mentioned constitution, and in the initial state of voltage application and when a high voltage is applied, abnormal alignment of liquid crystal does not occur around and between the spacers, so that a uniform liquid crystal is obtained. It is possible to create a display device.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing a liquid crystal display device.

[Explanation of symbols]

 1 Sealing member 2 Transparent substrate 3 Transparent electrode 4 Alignment control film 5 Transparent substrate 6 Transparent electrode 7 Alignment control film 8 Substrate 9 Spacer 10 Substrate 11 Nematic liquid crystal 12, 13 Polarizing sheet

Claims (3)

[Claims] 1. In a polymer fine particle used as a spacer for liquid crystal display, the area ratio of the surface area (S ₀ ) calculated assuming that the surface of the fine particle is smooth and the surface area (S _a ) actually measured ( liquid crystal display spacers S _a / S ₀₎ is characterized in that it is a 1.2 to 8. 2. The spacer for liquid crystal display according to claim 1, wherein the polymer fine particles are formed of a fluorine-based polymer having a fluorine content of 2 to 40% by weight. 3. The two glass substrates on which the alignment film and the transparent electrode are arranged are opposed to each other with the spacer for liquid crystal display according to claim 1 or 2, and liquid crystal is sealed between the glass substrates. Liquid crystal display device characterized by.