JPH11228698A - Fine particles of organopolysiloxane, production of the same and liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide fine particles for spacer capable of uniformly spraying on a substrate, having excellent elastic properties and uniform particle size. SOLUTION: This organopolysiloxane fine particles mainly comprising polysiloxane having (a) hydrocarbon groups and (b) OH groups directly bonded to silicon atoms in the particles, in which (i) carbons contained in the hydrocarbon groups directly bonding to silicon atoms is 5 to 35 wt.%. based on the weight of the particles, (ii) OH groups directly bonding to siliconfatoms is 1 to 8 meq/g based on the weight of the particles, and manifests (iii) 150 to 900 kg/ mm<2> of compressive elasticity modulus at 10% compression, (iv) 20 to 60% of average compressive strain rate (Cr)<m> , (v) 60 to 90% of average elastic recovery (Rt)<m> , (v) 0.5 to 50/2 μm of the average particle size.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to organopolysiloxane fine particles, a method for producing the same, and a liquid crystal display device in which the organopolysiloxane fine particles are interposed as spacers between electrodes of a liquid crystal cell. More specifically, the present invention relates to organopolysiloxane fine particles having excellent dispersibility, a method for producing the same, and a liquid crystal display device in which the organopolysiloxane fine particles are interposed as spacers between electrodes of a liquid crystal cell.

[0002]

BACKGROUND OF THE INVENTION A spacer is interposed between a pair of electrodes provided in a liquid crystal cell for a liquid crystal display device, and a liquid crystal material is sealed to form a liquid crystal layer. If it is not uniform, the image displayed on the liquid crystal cell may cause color unevenness or decrease in contrast at the time of lighting. Also, when switching the display image at a high speed or displaying an image with a wide viewing angle, it is required that the thickness of the liquid crystal layer inside the liquid crystal cell be uniform.

Further, in order to display a large screen without color unevenness in a currently used STN mode large screen liquid crystal display device, it is necessary to further uniform the thickness of the liquid crystal layer inside the liquid crystal cell. Have been.

Conventionally, in order to make the thickness of the liquid crystal layer inside the liquid crystal cell uniform, spherical particles having a uniform particle size are scattered and interposed between the electrodes of the liquid crystal cell, that is, a spacer between the electrodes of the liquid crystal cell. Organic particles such as polystyrene, silica fine particles, and the like are used as such particles.

However, when organic resin particles such as polystyrene are used as spacers between electrodes of a liquid crystal cell, these organic resin particles are too soft to maintain a uniform thickness of a liquid crystal layer inside the liquid crystal cell. There was a problem that it was difficult. For example, when a non-uniform pressure is applied to the liquid crystal layer inside the liquid crystal cell, the spacer is deformed in accordance with the variation in the pressure, and the thickness of the liquid crystal layer inside the liquid crystal cell cannot be maintained uniform.

When silica fine particles are used as a spacer between electrodes of a liquid crystal cell, if the particle size distribution of the silica fine particles is not sharp, the compression deformation of the silica fine particles is small, and the thickness of the liquid crystal layer inside the liquid crystal cell is reduced. However, there is also a problem that the non-uniformity is obtained. Further, when the liquid crystal display device is exposed to a low temperature, since the thermal expansion coefficient of the liquid crystal layer and the thermal expansion coefficient of the spacer are different inside the liquid crystal cell, a gap is formed between the electrode of the liquid crystal cell and the liquid crystal layer, so-called. There is also a problem that low-temperature bubbles are generated.

In order to solve the above problems, JP-A-6-250193 discloses that silica particles are prepared by hydrolyzing a hydrolyzable silicon compound, for example, tetraethoxysilane. It has been proposed to use silica fine particles in which silanol groups on the surface are esterified with an organic compound as a spacer between electrodes of a liquid crystal cell.

The silica fine particles produced by this method have appropriate hardness and mechanical resilience, and thus are suitable as spacers between electrodes of a liquid crystal cell. It was insufficient as a spacer between electrodes.

The fine particles conventionally used as the spacer particles are organic fine particles such as polystyrene, or inorganic particles such as silica, and are substantially hydrophobic or hydrophilic. For this reason, among such fine particles, when wet-spraying on the electrode substrate, there were some solvents in which the fine particles did not monodisperse depending on the solvent and could not be uniformly sprayed. Further, among such fine particles, when dry-spraying on the electrode substrate, there are also particles that are not charged uniformly due to charging of the fine particles, and furthermore, such fine particles tend to adhere to portions other than the electrode substrate. There was a problem.

As described above, even in the case of spacer particles having a uniform particle size and excellent elastic properties, the spacer particles may not be uniformly dispersed, and the effect based on the characteristics may not be sufficiently exhibited.

Japanese Patent Application Laid-Open No. Hei 7-140472 discloses that R ′ _m Si (OR ² ) _4-m (wherein R ′ and R ² each represent a specific organic group, and m represents 0 to 3). Is obtained by hydrolyzing and polycondensing the organosilicon compound represented by the formula (1), followed by heat treatment at a temperature of 100 to 1000 ° C. to obtain spacer particles for a liquid crystal cell having a specific compression modulus. Have been. The compression modulus of the spacer particles is controlled by the amount of residual organic groups after a part of the organic groups present inside the particles are thermally decomposed in the heat treatment step.

However, if the particle diameter is different, the amount of organic groups remaining inside the particles after the above heat treatment step is different.
It is difficult to control the amount of residual organic groups, and therefore, there is a large variation in the compressive deformation rate of each particle. Therefore, it is difficult to control the compression elastic modulus of spacer particles for liquid crystal cells by the amount of organic groups remaining inside the particles. There was a point. Also, since the amount of residual organic groups is different between the surface and the inside of the particle, the compression modulus is not uniform over the entire particle,
Further, voids are generated in the organic group portions inside the particles thermally decomposed in the heat treatment step, and as a result, there is a problem that the compressive strength of the obtained spacer particles for a liquid crystal cell is reduced.

For this reason, the present inventors produced organopolysiloxane fine particles by a specific method using an organosilicon compound. As a result, the amount of organic groups inside the fine particles was controlled without the heat treatment step as described above. And found that organopolysiloxane microparticles having a high elastic recovery rate and a uniform particle size can be obtained (Japanese Patent Application No. 7-2).
No. 13800).

However, since the obtained organopolysiloxane fine particles are hydrophobic, when they are used as spacers between electrodes, they may not be uniformly dispersed on the substrate in some cases. For this reason, depending on the application, it was necessary to make a part of the obtained hydrophobic organopolysiloxane fine particles hydrophilic. For this reason, a new treatment step such as hydrophilicity is required, and depending on the treatment, the compressive strength of the organopolysiloxane fine particles may be impaired.

[0015]

An object of the present invention is to solve the above-mentioned problems in the prior art, which can be uniformly dispersed on a substrate, has excellent elastic properties, and has a particle size. The object of the present invention is to provide a spacer fine particle having uniformity, a method for producing the spacer fine particle, and a liquid crystal display device in which the spacer fine particle is interposed as a spacer between electrodes of a liquid crystal cell. And

[0016]

SUMMARY OF THE INVENTION The organopolysiloxane fine particles according to the present invention contain, in the particles, hydrocarbon groups directly bonded to silicon atoms.
(a) and an organopolysiloxane fine particle mainly composed of a polysiloxane having an OH group (b) directly bonded to a silicon atom, wherein (i) a hydrocarbon group directly bonded to a silicon atom
The amount of carbon contained in (a) is 5 to 3 with respect to the weight of the fine particles.
(Ii) O directly bonded to silicon atoms
The amount of the H group (b) is 1 to 8 meq / g with respect to the fine particles, and (ii)
i) 10% compression modulus is 150 to 900 kg / mm ² , (iv) average compression deformation (C _r ) ^m is 20 to 60%, and (v) average elastic recovery (R _r ) ^m is 60 to 90%. (Vi) the average particle size is 0.5
５０50 μm.

The polyorganosiloxane fine particles according to the present invention
The method for manufacturing a child comprises the following steps (a) to (e).
It is a sign. (a) Equation (1): Si (OR¹)_FourOrganosilicon compound represented by
And equation (2): R'Si (OR ^Two)_ThreeOrganosilicon compound represented by
Mixture in a mixed solvent of water and an organic solvent.
Preparation of seed particle dispersion by disassembly and condensation polymerization
Where R¹And R^TwoIs a hydrogen atom or
Selected from kill, alkoxyalkyl and acyl groups
Wherein R ′ is a substituted or substituted organic group having 1 to 10 carbon atoms.
Is a group having 1 to 10 carbon atoms selected from unsubstituted hydrocarbon groups.
It is a machine base. (B) adding an alkali to the seed particle dispersion to form a seed;
(C) maintaining the pH of the seed particle dispersion at 6 to 9;
Meanwhile, the dispersion of the compound represented by the following formula (3) or (4)
One or more, and if necessary, represented by (5)
Compound and hydrolyze / condensate to form seed particles.
R′Si (OR)^Two)_Three (3) R'R "Si (OR^Three)_Two (Four)

[0018]

Embedded image

[0019] (wherein, R ^2, R 'is the same groups, R "is an organic group having 1 to 10 carbon atoms selected from substituted or unsubstituted hydrocarbon group, R ³ is a hydrogen atom or an alkyl group, an organic group having 1 to 10 carbon atoms selected from alkoxyalkyl groups and acyl groups, R ⁴ is,
A propyl or butyl group, Y is an organic group selected from a methyl group, a methoxy group, an ethyl group and an ethoxy group; M is an element selected from Groups 2 to 15 of the periodic table; N is an integer of 1 to 4, and m + n is an integer of 2 to 4. (D) a step of heating and aging the dispersion of the spherical fine particles, and (e) heating the spherical fine particles in a water-containing atmosphere at 100 to 600 ° C.
Process.

According to the above-mentioned method, organopolysiloxane fine particles having the above-mentioned properties can be produced. The liquid crystal display device according to the present invention has a liquid crystal cell provided with a pair of electrodes, and the organopolysiloxane fine particles according to the present invention are interposed as spacers between the electrodes.

[0021]

DETAILED DESCRIPTION OF THE INVENTION The organopolysiloxane fine particles according to the present invention and a method for producing the same will be described below.

[Organopolysiloxane Fine Particles] First,
The organopolysiloxane fine particles according to the present invention will be specifically described.

The fine particles according to the present invention are organopolysiloxane fine particles mainly composed of a polysiloxane having a hydrocarbon group (a) and an OH group (b) directly bonded to a silicon atom in the particles. The silicon content in such organopolysiloxane fine particles is preferably 50% in terms of SiO _2.
It is desirable that the content be from 90 to 90% by weight, more preferably from 60 to 80% by weight. Such fine particles are considered to have a so-called three-dimensional network structure based on a ladder structure.

The hydrocarbon group (a) directly bonded to a silicon atom includes a substituted or unsubstituted hydrocarbon group having 1 to 10 carbon atoms. Examples of the unsubstituted hydrocarbon group include an alkyl group (chain alkyl group or cyclic alkyl group), an alkenyl group, an aralkyl group, an aryl group, and the like.
The substituted hydrocarbon group is a group in which part or all of the hydrogen atoms of the unsubstituted hydrocarbon group is substituted with a non-hydrocarbon group or an element other than hydrogen, and specifically, a CH ₂ Cl group, CH ₂ F
Groups, γ-methacryloxypropyl group, γ-glycidoxypropyl group, aminopropyl group, 3,4-epoxycyclohexylethyl group, γ-mercaptopropyl group, trifluoropropyl group and the like. Such a hydrocarbon group (a) can be used as R'Si (OR ² ) ₃ or R'R "S used as a raw material when producing organopolysiloxane fine particles.
It is a group derived from R ′ and R ″ directly bonded to a silicon atom in the organosilicon compound represented by i (OR ³ ) _2. Such an organosilicon compound will be described later.

In the present invention, the hydrocarbon group directly bonded to the silicon atom in the organopolysiloxane fine particles is used.
The amount of carbon in (a) is from 5 to 35% by weight, preferably 10%.
It is desirably about 30% by weight.

If the amount of carbon is less than 5% by weight, fine particles having sufficient elastic properties cannot be obtained, the 10% compression elastic modulus described later exceeds 900 kg / mm ² , and the average elastic recovery rate increases. Low organopolysiloxane fine particles may result. If the carbon content is higher than 35% by weight,
In some cases, the organopolysiloxane fine particles have a 10% compression modulus lower than 150 kg / mm ^{2 and} a low average elastic recovery.

The determination of the amount of carbon is usually performed by using R'Si (OR ² ) ₃ or R'R "Si (OR ³ ),
It is calculated from the amounts of R ′ and R ″ contained in the organosilicon compound represented by ₂ .

In the present invention, the amount of the OH group (b) directly bonded to the silicon atom is desirably 1 to 8 meq / g, preferably 2 to 6 meq / g, based on the particle. When the amount of the OH group (b) is less than 1 meq / g, the sprayability in a dry system is reduced,
If it exceeds 8 meq / g, the elastic properties of the fine particles may be insufficient. The amount of the OH group (b) is calculated using a differential thermal analyzer, assuming that the weight loss of the organopolysiloxane fine particles at 100 to 350 ° C. is the generation of water due to the elimination of the OH group.

The 10% compression modulus of the organopolysiloxane fine particles according to the present invention is 150 to 900 kg.
/ mm ² , and preferably in the range of 200 to 700 kg / mm ² .

If the 10% compression modulus is less than 150 kg / mm ² , the thickness of the liquid crystal layer inside the liquid crystal cell may not be kept uniform due to the softness of the particles, and the pressure applied to each particle may be reduced. As a result, it is necessary to increase the number of sprays in order to suppress the deformation of the particles, and accordingly, quality and economic efficiency may decrease. On the other hand, when it is higher than 900 kg / mm ² , the above-mentioned low-temperature bubbles may be generated.

The method of evaluating the 10% compression modulus is as follows. The 10% compression modulus was measured using a micro compression tester (MCTM-200 manufactured by Shimadzu Corporation) as a measuring device, and using one fine particle having a particle size of D as a sample.
A load is applied to the sample at a constant loading speed, the particles are deformed until the compression displacement becomes 10% of the particle diameter, the load at 10% displacement and the compression displacement (mm) are obtained, and the particle size and the obtained compression load are obtained. , And the compression displacement are substituted into the following equation to determine by calculation.

K = (3 / √2) × F × S ^−3/2 × D ^−1/2 where K: 10% compression modulus (Kg / mm ² ) F: Compression load (Kg) S: Compressive displacement (mm) D: Particle diameter (mm)

In the present specification, 10% compression modulus was measured for each of 10 particles, and the average value of these values was used to evaluate the 10% compression modulus of the particles. The organopolysiloxane fine particles according to the present invention have an average elastic recovery (R _r ) ^m
Is in the range of 40 to 90%, preferably 70 to 90%. When the average elastic recovery is less than 40%, a predetermined liquid crystal layer cannot be maintained at a uniform thickness, and image unevenness may occur. 9 average elastic recovery
If it is higher than 0%, there is a problem that the liquid crystal display device is liable to cause display unevenness when receiving a shock and vibrating.

Further, the organopolysiloxane fine particles according to the present invention have an average compressive deformation (C _r ) ^m of 20 to 60%, preferably 25 to 50%. When the average compressive deformation ratio is less than 20%, the above-mentioned low-temperature bubbles may be generated because the particles are too hard.
If the average compressive deformation rate is higher than 60%, the thickness of the liquid crystal layer inside the liquid crystal cell may not be kept uniform because the particles are soft, and the pressure applied to the individual particles may be reduced. It is necessary to increase the number of sprays in order to suppress the deformation of, and the quality and economy may be reduced accordingly.

The average elastic recovery rate and the average compressive deformation rate are as follows:
It is determined as follows. Using the micro compression tester (MCTM-200 manufactured by Shimadzu Corporation), using a single fine particle having a particle size of D as a sample, load the sample at a constant load speed to a predetermined load value (reversal load value). Load,
When the particles are deformed, the displacement increases from zero according to curve A as the load increases, as shown in FIG.

Next, when the load is unloaded to a constant load value (origin load value) at the same unloading speed as the above-mentioned loading speed, the displacement gradually decreases according to the curve B. When the difference between the amount of displacement of the origin load value when the load and the displacement of the inverted load value and L _1, the difference in the amount of displacement of the load and each of the origin load value at the time of unloading and L _2, the sample Average elastic recovery rate R _r and compressive deformation rate C _r
Is calculated by the following formula: R _r = [(L ₁ −L ₂ ) / L ₁ ] × 100 _Cr = (L ₁ / D) × 100

In the present specification, the elastic recovery rate and the compressive deformation rate of each of the particles when the load value for the origin is set to 0.1 g and the reversal load value is set to 1.0 g for the ten particles are determined according to the above equations. The average elastic recovery rate and average compressive deformation rate of the particles were evaluated based on these average values.

Further, a load exceeding the above-mentioned reversal load value and the load value when the particles are broken are defined as the compressive strength. The average particle size of the organopolysiloxane fine particles according to the present invention is 0.5 to 50 μm, preferably 1 to 20 μm.
Is desirably within the range. Such an average particle diameter is set in consideration of the type of the liquid crystal display device, the required thickness of the liquid crystal layer, and the elastic characteristics. The average particle size is measured by observing a scanning electron micrograph.

It is desirable that such particles have a coefficient of variation CV of the particle diameter of 5% or less, preferably 1 to 3%. If the variation coefficient of the particle size exceeds 5%, the thickness of the liquid crystal layer cannot be kept uniform, which may cause image unevenness. Note that such a variation coefficient CV value is calculated by the following equation.

CV = (standard deviation of particle size (σ) / average particle size)
(Dn)) × 100

[0041]

(Equation 1)

Di: Particle size of individual particles Further, the agglomeration rate of the organopolysiloxane fine particles is desirably 5% or less, preferably 3% or less. Such agglomeration rate can be measured by a scanning electron microscope (SEM).
According to the observation of the photograph, a particle obtained by aggregating a plurality of particles is also represented as one particle, which is represented by a ratio of agglomerated particles in a total of 100 particles. If the agglomeration rate is more than 5%, it becomes difficult to uniformly spray, the spraying efficiency decreases, and cells with a uniform cell gap may not be obtained.

[Method for Producing Organopolysiloxane Fine Particles] Next, a method for producing the organopolysiloxane fine particles according to the present invention will be described.

The organopolysiloxane fine particles according to the present invention are produced by the following steps. (a) Step of preparing seed particle dispersion In the present invention, first, an organosilicon compound (a-1) represented by the formula (1): Si (OR ¹ ) ₄ and a formula (2): R′Si ( A mixture of the organosilicon compound (a-2) represented by OR ² ) ₃ is hydrolyzed and polycondensed in a mixed solvent of water and an organic solvent to prepare a dispersion of seed particles.

As a method for preparing such seed particles,
A conventionally known method can be adopted. R ¹ and R ² in the above formula
Represents a hydrogen atom or an organic group having 1 to 10 carbon atoms selected from an alkyl group, an alkoxyalkyl group and an acyl group. The organosilicon compound (a-1) and the organosilicon compound (a-
And 2) are preferably the same group from the viewpoint that they are simultaneously hydrolyzed in a mixed solvent of water and an organic solvent, and co-condensation-polymerizes these hydrolysates.

R ′ in the above formula represents a hydrocarbon group having 1 to 10 carbon atoms selected from a substituted or unsubstituted hydrocarbon group. Among them, examples of the unsubstituted hydrocarbon group include an alkyl group (chain alkyl group or cyclic alkyl group), an alkenyl group, an aralkyl group, an aryl group, and the like.
The substituted hydrocarbon group is a group in which part or all of the hydrogen atoms of a hydrocarbon are substituted with a non-hydrocarbon group or an element other than hydrogen, specifically, a CH ₂ Cl group, a CH ₂ F group, a chloromethyl group. Groups, γ-methacryloxypropyl group, γ-glycidoxypropyl group, aminopropyl group, 3,4-epoxycyclohexylethyl group, γ-mercaptopropyl group, trifluoropropyl group and the like.

Specific examples of the organosilicon compound (a-1) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetramethylmethoxysilane,
Examples include tetraethylethoxysilane and tetraacetoxysilane.

Specific examples of the organosilicon compound (a-2) include methyltrimethoxysilane, methyltriethoxysilane, methyltriisopropoxysilane, methyltris (methoxyethoxy) silane, ethyltrimethoxysilane, vinyltrimethoxysilane, Phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-
Glycidoxypropyltrimethoxysilane, methyltriacetoxysilane, phenyltriacetoxysilane and the like can be mentioned.

In the step (a), the mixing ratio of the organosilicon compound (a-1) and the organosilicon compound (a-2) is determined based on 1 mol of the organosilicon compound (a-1). 2) 0.1 to 3.
Preferably, 0 moles are mixed.

In the step (a), a mixed solvent of water and an organic solvent is used as a solvent. It is preferable that water is contained at a ratio of 10 to 100 parts by weight with respect to 100 parts by weight of the organic solvent.

As the organic solvent, any organic solvent compatible with water can be used without any particular limitation. For example, it is selected from alcohols, glycols, glycol ethers, ketones and the like. One or two
More than one species is used.

In step (a), an alkali such as ammonia is added to a solvent as a catalyst for hydrolysis of the organosilicon compounds (a-1) and (a-2). It is preferable that the mixed solvent with the solvent is kept alkaline.

The organosilicon compounds (a-1) and (a-2) are simultaneously hydrolyzed in a mixed solvent of water and an organic solvent, and these hydrolysates are copolycondensed to prepare seed particles. However, when the mixed solvent of water and the organic solvent is kept alkaline, these reactions are promoted.

The above reaction temperature is preferably about 10 to 20 ° C. The concentration of the seed particles in the seed particle dispersion liquid obtained as described above is preferably about 0.05 to 5% by weight in terms of SiO ₂ .

The average particle size of the obtained seed particles is preferably 0.05 to 2.0 μm. (b) seed particle stabilization stepIn the present invention, the seed particle dispersion obtained in step (a),
Stabilize the seed particles by adding alkali (note that
In the present specification, the dispersion liquid of the seed particles stabilized by adding the alkali is sometimes referred to as a heel sol).

When the dispersion is stabilized by adding an alkali as described above, precipitation due to aggregation of the seed particles can be prevented. Note that if the seed particles are aggregated,
In (c), the hydrolyzate of the organosilicon compound adheres to the joints of the aggregated particles, and the particles may grow from the joints, so that particles having a uniform particle diameter may not be obtained.

As the alkali added to stabilize the dispersion, ammonia gas, aqueous ammonia, alkali metal hydroxides such as sodium hydroxide, quaternary ammonium salts, amines and the like are used. These can be used alone or in combination. Also,
In order to stabilize the dispersion, the dispersion may be irradiated with ultrasonic waves. Furthermore, it is desirable that the stabilized dispersion is brought into contact with a cation exchange resin to reduce alkali and ammonia, and the alkali at this time has an alkali concentration in the finally produced fine particles of 100 ppm or less, preferably It is desirable that the content be reduced to 50 ppm or less, particularly preferably 10 ppm or less.

(C) Step of Growing Seed Particles Next, the heel sol obtained in the above step (b) is added to an alkali and one or more kinds of organosilicon compounds represented by the following formula (3) or (4). , And, if necessary, by adding an acetylacetonato chelate compound represented by the following formula (5) and subjecting it to hydrolysis and polycondensation, to grow seed particles to form a dispersion of spherical fine particles having an arbitrary particle size. Prepare.

Formula (3): R′Si (OR ² ) ₃ (In the formula (3), R ² and R ′ are the same groups as described above, and the formula (2)
In the step (c), the organosilicon compound represented by is referred to as an organosilicon compound (c-1). Formula (4): R′R ″ Si (OR ³ ) ₂ (In Formula (4), R ′ and R ″ may be the same or different, and each represents a substituted or unsubstituted hydrocarbon group. And R ³ is the same group as R ^1, and the organosilicon compound represented by the formula (4) is referred to as an organosilicon compound (c-2). Equation (5):

[0060]

Embedded image

(In the formula (5), R ⁴ is a propyl or butyl group, Y is one kind of an organic group selected from a methyl group, a methoxy group, an ethyl group and an ethoxy group, and M is
An element selected from Groups 2 to 15 of the periodic table,
m is an integer of 0 to 3; n is an integer of 1 to 4;
+ N is an integer of 2 to 4. ) The organosilicon compound (c-1) used in this step (c) and
When R ′ in (c-2) and R ″ in the organosilicon compound (c-2) both have a large number of carbon atoms, the organosilicon compound (c-
When 1) and / or (c-2) are added to the seed particle dispersion, a gel is easily generated in the seed particle dispersion, and the growth of the seed particles becomes difficult.

Accordingly, R ′ and R ″ are each preferably a group having a small number of carbon atoms such as a methyl group, a vinyl group, a trifluoromethyl group, a phenylamino group, etc. The organosilicon compound (c-1) )), The organosilicon compound (a-2) used in the step (a) can be used.

Specific examples of the organosilicon compound (c-2) include dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldiethoxysilane, phenylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, dimethylacetoxysilane and the like. Is mentioned.

As a specific example of the acetylacetonato chelate compound represented by the above formula (5), dibutoxy-
Bisacetylacetonatozirconium, tributoxy
Monoacetylacetonatozirconium, triisopropoxy-monoacetylacetonatotitanium, dibutoxy-bisacetylacetonatotitanium, lead bisacetylacetonato, trisacetylacetonatoiron, dibutoxy-bisacetylacetohafnium, tributoxy-monoacetylacetonatohafnium And the like.

In the step (c), only the organosilicon compound (c-2) may be added to the seed particle dispersion, but at least about 50 mol% or more of the organosilicon compound (c-1) should be added. Is preferred.

In the step (c), the compound of the above (3) to (5)
In addition to the product, the above formula (1): Si (OR ¹)_FourOrganic represented by
A small amount of a silicon compound may be added. In the above step (c),
When adding the compound to the heel sol, the addition speed of the compound
If the temperature is too fast, the seed particles will aggregate in the heel sol
Or the seed particles grow unevenly,
An organopolysiloxane fine particle with a sharp particle size distribution
Particles may not be obtained. Therefore, the addition of compounds
The rate is 0.001 to 1 g of water contained in the dispersion medium.
It is preferably 0.05 g / hour.

In the present invention, in the step (c), the compound is added to grow the seed particles while maintaining the pH of the seed particle dispersion in the range of 6 to 9. Dispersion pH
Is smaller than 6 or higher than 9, the dispersibility of the obtained fine particles may be reduced.

For such pH adjustment, an alkali such as ammonia is usually used. In the present invention, in particular, it is desirable that such a fluctuation in pH at the growth stage be in a range of ± 30%, preferably ± 10% with respect to the pH at the initial stage of compound addition. For this reason, when adding the compound to the seed particle dispersion, it is desirable to simultaneously and continuously add an alkaline aqueous solution.

As described above, when the alkali and one or more of the compounds represented by the above formula (3) or (4) and, if necessary, the above formula (5) are added to the seed particle dispersion, These compounds are hydrolyzed and then the hydrolysates or hydrolysates are polycondensed on the surface of the seed particles to be laminated, whereby the seed particles grow.

The reaction temperature in step (c) is lower than the reaction temperature in step (a), and is preferably in the range of about -10 to 20 ° C. (d) aging step Then, the fine particle dispersion obtained in the step (c) is subjected to a step
The spherical fine particles are aged while maintaining the same temperature as (c) or a higher temperature. By this step, the particle diameter of the obtained fine particles becomes more uniform. The aging temperature and time are preferably maintained at a temperature of about 20 to 90 ° C, preferably 50 to 80 ° C, for about 0.5 to 24 hours.

When the aging temperature is lower than 20 ° C., particles having a fine particle diameter are newly formed, and since the silica component is not sufficiently precipitated, a large amount of the silica component remains after being dissolved, making it difficult to obtain monodispersed particles. Sometimes. Aging temperature is 90
If the temperature is higher than ° C., the particles may aggregate with each other or may form fused particles.

The matured spherical fine particles are separated from the spherical fine particle dispersion by a centrifugation method or the like, and dried if necessary. (e) Water-containing atmosphere treatment step After the separation, the spherical fine particles are subjected to a heat treatment in a water-containing atmosphere. The heating temperature at this time is preferably in the range of 100 to 600C, preferably 150 to 500C.

If the heating temperature is lower than 100 ° C., the elasticity of the fine particles may decrease, and if the heating temperature exceeds 600 ° C., the dispersibility of the fine particles may decrease. As the moisture-containing atmosphere, air containing moisture and / or an inert gas is used, and the proportion of moisture at this time is preferably in the range of 20 to 90% in terms of relative humidity, and particularly preferably 50 to 80%. % Is desirable.

In such a moisture-containing atmosphere treatment,
In order to promote and complete the polycondensation of the organopolysiloxane in the spherical fine particles, if necessary, the spherical particles may be calcined, or the spherical fine particles may be irradiated with electromagnetic waves such as ultraviolet rays.

Through the steps described above, polysiloxane having a hydrocarbon group (a) directly bonded to a silicon atom and an OH group (b) directly bonded to a silicon atom is contained in the particles as a main component. Then, organopolysiloxane fine particles having the characteristics (i) to (vi) can be produced.

Finally, the liquid crystal display device according to the present invention will be specifically described.

The liquid crystal display device according to the present invention has a liquid crystal cell having a pair of electrodes, wherein the organopolysiloxane fine particles are interposed as spacers between the electrodes.

The liquid crystal cell has the same structure as a known liquid crystal cell except that the organopolysiloxane fine particles according to the present invention are interposed and the distance between the electrodes of the liquid crystal cell is kept constant by the fine particles. ing.

In the liquid crystal display device according to the present invention, organopolysiloxane fine particles may be interposed as spacers between the electrodes of the liquid crystal cell over the entire electrode surface.
It may be interposed in the adhesive layer at the peripheral portion between the electrodes.

When the organopolysiloxane fine particles according to the present invention are used as a spacer between electrodes of a liquid crystal cell, the number of sprays can be reduced, and damage to the electrode surface or the protective film can be reduced. Further, when the organopolysiloxane fine particles according to the present invention are used, the thickness of the liquid crystal layer inside the liquid crystal cell caused by the small compression deformation of the spacer particles becomes nonuniform, and the heat of the liquid crystal layer inside the liquid crystal cell is reduced. Low-temperature bubbles generated due to the difference between the expansion coefficient and the thermal expansion coefficient of the spacer can be reduced.

When the organopolysiloxane fine particles according to the present invention are used as a spacer between electrodes of a liquid crystal cell, the particle size and CV value of the organopolysiloxane fine particles are selected according to the required cell gap size and uniformity. Is done. When used as an interelectrode spacer in this way, the uniformity of the particle size is particularly important, and the CV value as an index thereof is desirably 5% or less, particularly preferably in the range of 1 to 3%.

When the organopolysiloxane fine particles according to the present invention are used as a spacer between electrodes of a liquid crystal cell, the organopolysiloxane fine particles are applied to one of the electrode surfaces (if a protective film is formed on the electrode surface, the surface of the protective film is protected). ) Is uniformly dispersed by a wet method or a dry method, and then on the organopolysiloxane fine particles dispersed on one electrode surface (or the surface of the protective film), and on the other electrode surface (or the surface of the protective film).
The liquid crystal material is filled in the cell gap formed by this, and the peripheral portions of both electrode surfaces are bonded with a sealing resin, and sealed, thereby providing a liquid crystal display device according to the present invention. The liquid crystal cell used is obtained. In this case, the organopolysiloxane fine particles according to the present invention may be mixed in the sealing resin.

In the liquid crystal cell used in the liquid crystal display device according to the present invention, the sealing resin in which the organopolysiloxane fine particles according to the present invention are mixed is applied to the periphery of one electrode surface (or the surface of the protective film). Is applied except for the liquid crystal material injection port, and then the other electrode surface (or the surface of the protective film) is placed and overlapped. After the liquid crystal material is injected from the liquid crystal material injection port, the liquid crystal material is injected. It can also be obtained by sealing the inlet with a sealing resin.

[0084]

According to the present invention, organopolysiloxane fine particles having a low agglomeration rate, a very sharp particle size distribution, and a high compression modulus, elastic recovery rate and compression deformation rate are provided.

Since such organopolysiloxane fine particles have a hydrophilic group in addition to a hydrophobic group, they are uniformly dispersed in a solvent containing water and the like in particular, and thus have excellent dispersibility. Is provided.

In addition, since the fine particles have a hydrophilic group, the charge of the fine particles is suppressed by the dry spraying, and the organopolysiloxane fine particles which are less likely to adhere to portions other than the electrode surface or the protective film are provided.

When the organopolysiloxane fine particles according to the present invention are used as a spacer between electrodes of a liquid crystal cell, the particle size distribution of the fine particles is sharp, so that the thickness of the liquid crystal layer formed between the electrodes of the liquid crystal cell is made uniform. Can be held. Also, since the compression modulus is high, the number of sprays per unit area can be reduced. Further, since the fine particles have a high elastic recovery rate and a high compressive deformation rate, low-temperature bubbles generated inside the liquid crystal cell can be prevented, and a high-performance liquid crystal display device without image unevenness can be provided.

[0088]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0089]

Example 1 [Preparation of Seed Particles] A solution (solution A) was prepared by dissolving 8 g of methyltrimethoxysilane and 8 g of tetramethoxysilane in 350 g of ethanol. On the other hand, a mixed solution (solution B) of 6 g of pure water, 78 g of 28% ammonia water, and 350 g of ethanol was prepared.

The above solution A and solution B were mixed and stirred at 20 ° C. for 3 hours to carry out hydrolysis and polycondensation of alkoxysilane to prepare a seed particle dispersion. 3.3% aqueous 1% by weight potassium hydroxide solution was added to the resulting seed particle dispersion.
g was added to stabilize the seed particles (a heel sol). The pH at this time was 12. The average particle size of the seed particles in this seed particle dispersion was measured using a centrifugal particle size distribution analyzer (CAPA-500, manufactured by Horiba, Ltd.).
It was 0.15 μm.

[Growth of Seed Particles] The seed particle dispersion was heated and concentrated until the obtained seed particle dispersion reached 160 g, and then the amounts of alkali and ammonia were reduced using 10 cc of a cation exchange resin. 5000 g of pure water and 250 g of butanol were added to the seed particle dispersion. The seed particle dispersion thus diluted was cooled to 0 ° C., and while maintaining this temperature, 500 g of methyltrimethoxysilane was added dropwise to the seed particle dispersion at a rate of 0.005 g / pure water-g · hour. . At this time, together with methyltrimethoxysilane, an aqueous ammonia solution having a concentration of 0.028% was added at an addition rate of about 0.012 g / pure water-g · hour, and while maintaining the pH of the seed particle dispersion at 8.5. Then, methyltrimethoxysilane was hydrolyzed and polycondensed on the seed particles to grow the seed particles.

After stirring at 20 ° C. for 2 hours, the mixture was further heated to 80 ° C. and aged for 5 hours. After aging, the fine particles were separated from the liquid, dried, and heated at 250 ° C. while supplying air at a relative humidity of 50%.

With respect to the obtained organopolysiloxane fine particles, the amount of OH groups and carbon directly bonded to silicon, the average particle size, the CV value, the 10% compression modulus, the average elastic recovery (R _r ) ^m and the average The compression deformation rate (C _r ) ^m was measured.

The amount of the OH group was calculated from the weight loss in the temperature range of 100 to 350 ° C. by the differential thermal analysis as described above. As a result, the OH group content was 6% by weight based on the particles.
(5.3 meq / g). In addition, since the amount of carbon cannot be accurately determined by chemical analysis or the like, it was calculated from the amount of alkoxysilane used in the production as follows.

In the case of Example 1, since 8 g of methyltrimethoxysilane and 8 g of tetramethoxysilane were used as alkoxysilane in the production process of seed particles and 500 g of methyltrimethoxysilane were used in the particle growth process, The amount is calculated as follows.

Amount of carbon in hydrocarbon groups directly bonded to silicon atoms in seed particles: 8 g of CH ₃ —Si— (OCH ₃ ) ₃ is converted to CH ₃ —S
When converted to iO _3/2 , it is 3.94 g, and the carbon content is 3.94 x 1
2 / (15 + 28 + 24) = 0.71g.

When 8 g of Si— (OCH ₃ ) ₄ is converted into SiO ₂ ,
3.16 g, and the carbon content is 0 g. Carbon amount in methyltrimethoxysilane used during grain growth: 500 g of CH ₃ —Si— (OCH ₃ ) ₃ is 246.32 g in terms of CH ₃ —SiO _3/2 , and the carbon amount is 246.32 × 12 / (15 + 2
8 + 24) = 44.11 g.

The total carbon amount is the total amount of the carbon amount in the seed particles and the carbon amount in the methyltrimethoxysilane used during growth, and is 0.71 + 44.11 = 44.82 g. This total carbon amount is the total fine particle weight (3.94 + 3.16 + 246.32 = 253.42 g)
To 17.7% by weight. In consideration of the measured OH group content (4.8% by weight in terms of H ₂ O), the amount of carbon directly bonded to silicon in the particles is (1-0.048) × 0.177 =
0.169, ie 16.9% by weight.

The average particle size of the organopolysiloxane fine particles was measured by observation with a scanning electron microscope photograph, and the CV value was calculated from the average particle size. The 10% compressive modulus, the average elastic recovery (R _r ) ^m and the average compressive deformation (C _r ) ^m were measured by the methods described above.

Table 1 shows the results.

[0101]

[Example 2] [Preparation of seed particles] Liquid A and liquid B prepared in Example 1 were mixed, stirred at 25 ° C for 3 hours, and hydrolyzed and polycondensed with alkoxysilane to obtain a seed particle dispersion. Prepared. Further, 3.3 g of a 1% by weight aqueous solution of potassium hydroxide was added, and ultrasonic treatment was further performed for 10 minutes to stabilize the seed. The pH at this time was 12. The average particle size of the seed particles in the seed particle dispersion was 0.15 μm as measured by a centrifugal particle size distribution measuring method.
m.

[Growth of Seed Particles] The obtained seed particle dispersion was concentrated by heating to 160 g, and then the amount of alkali and ammonia was reduced using 10 cc of a cation exchange resin. Pure water 50 was added to the seed particle dispersion.
After the addition of 00 g and 250 g of butanol, the seed particle dispersion was cooled to 0 ° C. and, while maintaining this temperature,
Methyltrimethoxysilane 40 was added to this seed particle dispersion.
A mixed solution of 0 g and 100 g of vinyltrimethoxysilane was added dropwise at an addition rate of 0.005 g / pure water-g · hour. At this time, an ammonia aqueous solution having a concentration of 0.028% was added to about 0.02%.
The pH of the seed particle dispersion was maintained at 8.0 while adding at a rate of 12 g / pure water-g · hour, and methyltrimethoxysilane and vinyltrimethoxysilane were hydrolyzed and polycondensed on the seed particles. To grow the seed particles.

Next, after stirring at 20 ° C. for 2 hours, the mixture was further heated to 80 ° C. and aged for 5 hours. After aging, the fine particles were separated from the liquid, dried, and then heated at 220 ° C. while supplying air at a relative humidity of 60%.

For the obtained organopolysiloxane fine particles, the amount of carbon in the hydrocarbon group directly bonded to silicon,
Amount of OH groups bonded to silicon, average particle size, CV value, 10%
The compression modulus, the average elastic recovery (R _r ) ^m and the average compression deformation (C _r ) ^m were measured.

Table 1 shows the results.

[0106]

Example 3 Fine particles obtained in the same manner as in Example 1 were
Separated from the fine particle dispersion, dried, and heated at 400 ° C. while supplying air at a relative humidity of 70% to obtain organopolysiloxane fine particles.

For the obtained organopolysiloxane fine particles, the amount of carbon in the hydrocarbon group directly bonded to silicon,
Amount of OH groups directly bonded to silicon, average particle size, CV value, 1
The 0% compression modulus, the average elastic recovery (R _r ) ^m and the average compression deformation (C _r ) ^m were measured.

Table 1 shows the results.

[0109]

Comparative Example 1 [Preparation of Seed Particles] A solution (solution A) was prepared by dissolving 8 g of methyltrimethoxysilane and 8 g of tetramethoxysilane in 350 g of ethanol. On the other hand, a mixed solution (solution B) of 6 g of pure water, 78 g of 28% ammonia water, and 350 g of ethanol was prepared.

The liquids A and B were mixed, stirred at 20 ° C. for 3 hours, and the alkoxysilane was hydrolyzed and polycondensed to obtain a seed particle dispersion. The average particle size of the seed particles in the seed particle dispersion was 0.15 μm as measured by a centrifugal particle size distribution measuring method.

[Growth of Seed Particles] After the seed particle dispersion was heated and concentrated until the obtained seed particle dispersion reached 160 g, pure water 5000 was added to the concentrated seed particle dispersion.
g and 250 g of butanol were added. 0.28% aqueous ammonia 100 was added to the seed particle dispersion thus diluted.
g was added. The pH at this time was 10.5. The seed particle dispersion to which the aqueous ammonia was added was cooled to -5 ° C.
While maintaining the temperature, 500 g of methyltrimethoxysilane was added to the seed particle dispersion in an amount of 0.005.
g / pure water-g · hour was added dropwise, and methyltrimethoxysilane was hydrolyzed and polycondensed on the seed particles to grow the seed particles. The pH after dropping was 8.5.

After completion of the dropwise addition, the liquid was heated to 60 ° C., and stirred at this temperature for 5 hours to ripen the grown seed particles.
After aging, the fine particles are separated from the liquid, dried, and dried in air for 30 minutes.
Baking at 0 ° C.

For the obtained organopolysiloxane fine particles, the amount of carbon in the hydrocarbon group directly bonded to silicon,
Amount of OH groups bonded to silicon, average particle size, CV value, 10%
The compression modulus, the average elastic recovery (R _r ) ^m and the average compression deformation (C _r ) ^m were measured, and the results are shown in Table 1.

[0114]

Comparative Example 2 [Growth of Seed Particles] The seed particle dispersion obtained in Comparative Example 1 was heated and concentrated to 160 g, and 5000 g of pure water and 250 g of butanol were added to the concentrated seed particle dispersion. . 10 g of 28% aqueous ammonia was added to the seed particle dispersion thus diluted. The pH at this time was 13. The seed particle dispersion to which the aqueous ammonia was added was cooled to −5 ° C., and while maintaining this temperature, 450 g of methyltrimethoxysilane and dimethylmethoxysilane 5 were added to the seed particle dispersion.
0 g of the mixed solution was added dropwise at an addition rate of 0.005 g / pure water-g · hour, and methyltrimethoxysilane and dimethylmethoxysilane were hydrolyzed and polycondensed on the seed particles to grow the seed particles. The pH after completion of the dropwise addition was 10.

After the completion of the dropwise addition, the liquid was heated to 60 ° C. and stirred at this temperature for 5 hours to ripen the grown seed particles.
The obtained fine particles are separated from the liquid, dried, and then dried in air.
Baking at 0 ° C.

For the obtained organopolysiloxane fine particles, the amount of carbon in the hydrocarbon group directly bonded to silicon,
Amount of OH groups bonded to silicon, average particle size, CV value, 10%
The compression modulus, average elastic recovery (R _r ) ^m and average compression deformation (C _r ) ^m were measured.

Table 1 shows the results.

[0118]

[Table 1]

[0119]

Embodiment 4 A pair of transparent substrates with transparent electrodes used for a liquid crystal cell of a liquid crystal display device were prepared. In this transparent substrate with a transparent electrode, an ITO thin film as a transparent electrode and an alignment film for aligning liquid crystal compound molecules contained in a liquid crystal material in a predetermined direction are formed on one surface of a glass substrate in this order.

Next, the organopolysiloxane fine particles obtained in Example 1 were sprayed on the surface of the alignment film formed on one of the transparent substrates with a transparent electrode. Spraying method is pure water 350cc,
120 cc of isopropyl alcohol, ethyl alcohol 3
A dispersion liquid was prepared by dispersing the organopolysiloxane fine particles obtained in Example 1 in a 0 cc mixed solvent so as to have a concentration of 1% by weight while irradiating ultrasonic waves with stirring. Using a spray nozzle (Lumina PR-10) having a nozzle diameter of 0.5 mmφ, the spray liquid was sprayed at a pressure of 3 kg / cm ² at a distance of 70 cm between the nozzle and the alignment film surface.

At this time, the average particle scattering density was 130 particles /
a mm ^2, the maximum value of the dispersion density 147 / mm ^2, the minimum value is 114 pieces / mm ^2, the variation was 13%.
In addition, no aggregates (adhered particles) of a plurality of particles were observed in each surface where the scatter density was measured. The spray density was measured as follows using a liquid crystal spacer counter device (ED-7510, manufactured by EDEC Co., Ltd.). Specifically, 10 imaginary horizontal lines and 10 imaginary vertical lines were provided at equal intervals on the scatter surface, the scatter density at 100 intersections was determined, and the average of the calculated values was taken as the average particle scatter density. The dispersion of the application density was calculated from the average particle application density calculated above.

Then, the surface of the alignment film formed on the other transparent substrate with a transparent electrode was brought into contact with the dispersed organopolysiloxane fine particles, and the two transparent substrates with a transparent electrode were overlapped. A liquid crystal material was filled in the gap between the alignment films of the transparent substrates with both transparent electrodes thus formed, and the peripheral portions of both substrates were bonded together with a sealing resin to form a liquid crystal cell. In addition, the created liquid crystal cell is driven in the STN mode.

The operation of cooling the liquid crystal cell prepared as described above from room temperature to −40 ° C. was repeated 10 times, and bubbles were observed each time at −40 ° C., but low-temperature bubbles were observed inside the liquid crystal cell. Was not done.

Further, when the liquid crystal cell prepared as described above was mounted on a liquid crystal display and the liquid crystal display was driven, no unevenness of the displayed image was observed.

[0125]

Example 5 In the same manner as in Example 4, the organopolysiloxane fine particles obtained in Example 2 were sprayed on the surface of the alignment film formed on the transparent substrate with a transparent electrode.

The average particle distribution density was 125 particles / mm ² , the maximum value of the distribution density was 135 particles / mm ² , and the minimum value was 11 particles / mm ² .
4 pieces / mm ² , and the variation was 9%. Aggregates of multiple particles (coherent particles) on the surface where the scatter density was measured
Was not observed.

Next, the surface of the alignment film formed on the other transparent substrate with a transparent electrode was brought into contact with the dispersed organopolysiloxane fine particles, and the two transparent substrates with a transparent electrode were overlapped. The operation of cooling to −40 ° C. was repeated 10 times, and bubbles were observed each time at −40 ° C., but no low-temperature bubbles were observed inside the liquid crystal cell.

Further, when the liquid crystal cell prepared as described above was mounted on a liquid crystal display and the liquid crystal display was driven, no unevenness of the displayed image was observed.

[0129]

Example 6 In the same manner as in Example 4, the organopolysiloxane fine particles obtained in Example 3 were sprayed on the surface of the alignment film formed on the transparent substrate with a transparent electrode.

The average particle distribution density was 123 particles / mm ² , the maximum value of the distribution density was 143 particles / mm ² , and the minimum value was 10 particles / mm ² .
The number was 5 / mm ² and the variation was 16%. No aggregates (adhered particles) of a plurality of particles were observed on the surface where the scatter density was measured.

Then, the surface of the alignment film formed on the other transparent substrate with a transparent electrode is brought into contact with the dispersed organopolysiloxane fine particles, and the two transparent substrates with a transparent electrode are overlapped. The operation of cooling to −40 ° C. was repeated 10 times, and bubbles were observed each time at −40 ° C., but no low-temperature bubbles were observed inside the liquid crystal cell.

Further, when the liquid crystal cell prepared as described above was mounted on a liquid crystal display device and the liquid crystal display device was driven, no unevenness of the displayed image was observed.

[0133]

Comparative Example 3 In the same manner as in Example 4, the organopolysiloxane fine particles obtained in Comparative Example 1 were sprayed on the surface of an alignment film formed on a transparent substrate with a transparent electrode.

The average particle distribution density was 128 particles / mm ² , the maximum value of the distribution density was 173 particles / mm ² , and the minimum value was 90 particles / mm ² .
Pieces / mm ² , and the variation was 36%. In addition, agglomerates of a plurality of particles were present on the surface where the spray density was measured.

Then, the surface of the alignment film formed on the other transparent substrate with a transparent electrode was brought into contact with the dispersed organopolysiloxane fine particles, and the two transparent substrates with a transparent electrode were overlapped. The operation of cooling to −40 ° C. was repeated 10 times, and air bubbles were observed at −40 ° C. every time. As a result, low-temperature air bubbles were observed inside the liquid crystal cell after the eighth cooling operation.

When the liquid crystal cell thus produced was mounted on a liquid crystal display device and the liquid crystal display device was driven, display image unevenness was observed.

[0137]

Comparative Example 4 In the same manner as in Example 4, the organopolysiloxane fine particles obtained in Comparative Example 2 were sprayed on the surface of an alignment film formed on a transparent substrate with a transparent electrode.

The average particle density was 120 particles / mm ² , the maximum value was 166 particles / mm ² and the minimum value was 78.
Pieces / mm ² , and the variation was 38%. In addition, agglomerates of a plurality of particles were present on the surface where the spray density was measured.

Next, the surface of the alignment film formed on the other transparent substrate with a transparent electrode was brought into contact with the dispersed organopolysiloxane fine particles, and the two transparent substrates with a transparent electrode were overlapped. The operation of cooling from −40 ° C. to −40 ° C. was repeated 10 times, and bubbles were observed at −40 ° C. each time. As a result, low-temperature bubbles were observed inside the liquid crystal cell after the fifth cooling operation.

When the liquid crystal cell thus produced was mounted on a liquid crystal display device and the liquid crystal display device was driven, display image unevenness was observed.

[Brief description of the drawings]

FIG. 1 is a drawing for explaining an elastic recovery rate and a compressive deformation rate.

Claims (4)

[Claims] 1. Organopolysiloxane fine particles containing, as a main component, a polysiloxane having a hydrocarbon group (a) directly bonded to a silicon atom and an OH group (b) directly bonded to a silicon atom in the particle. (I) the amount of carbon contained in the hydrocarbon group (a) directly bonded to the silicon atom is 5 to 35% by weight based on the weight of the fine particles, and (ii) the OH group directly bonded to the silicon atom ( the amount of b) is a 1~8meq / g with respect to fine particles, is (iii) 10% compressive elasticity modulus 150~900Kg / mm ^2, (iv) an average pressure change rate (C _r) ^m 20~60 %, (V) an average elastic recovery (R _r ) ^m of 60 to 90%, and (vi) an average particle diameter of 0.5 to 50 μm. 2. An organopoly comprising the following steps (a) to (e):
A method for producing siloxane fine particles. (a) Equation (1): Si (OR¹)_FourOrganosilicon compound represented by
And equation (2): R'Si (OR ^Two)_ThreeOrganosilicon compound represented by
Mixture in a mixed solvent of water and an organic solvent.
Preparation of seed particle dispersion by disassembly and condensation polymerization
Where R¹And R^TwoIs a hydrogen atom or
Selected from kill, alkoxyalkyl and acyl groups
Wherein R ′ is a substituted or substituted organic group having 1 to 10 carbon atoms.
Is a group having 1 to 10 carbon atoms selected from unsubstituted hydrocarbon groups.
It is a machine base. (B) adding an alkali to the seed particle dispersion to form a seed;
(C) maintaining the pH of the seed particle dispersion at 6 to 9 while stabilizing the solution.
The seed particle dispersion is represented by the following formula (3) or (4)
One or more compounds, and if necessary (5)
The compound represented by
A step of preparing a spherical fine particle dispersion by growing particles, R'Si (OR^Two)_Three (3) R'R "Si (OR^Three)_Two (4)(Where R^Two, R ′ are the same groups as described above, and R ″ is
1 to 1 carbon atoms selected from substituted or unsubstituted hydrocarbon groups
10 organic groups, R^ThreeIs a hydrogen atom or an alkyl
Selected from a group, an alkoxyalkyl group and an acyl group
An organic group having 1 to 10 carbon atoms;^FourIs propyl or
Is a butyl group, Y is a methyl group, a methoxy group, an ethyl group and an ethoxy group.
And M is an organic group selected from the following groups:
M is an integer of 0 to 3; n is an integer of 1 to 4;
+ N is an integer of 2 to 4. (D) a step of heating and aging the dispersion of the spherical fine particles, and (e) subjecting the spherical fine particles to a water-
Step of treating at ° C. 3. The organopolysiloxane microparticles obtained by the method according to claim 2 have the physical properties according to claim 1.
3. The method for producing organopolysiloxane fine particles according to 1.). 4. A liquid crystal display device comprising a liquid crystal cell having a pair of electrodes, wherein the organopolysiloxane fine particles according to claim 1 are interposed as spacers between the electrodes.