JP3333134B2 - Liquid crystal display element spacer and liquid crystal display element using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a spacer for a liquid crystal display device and a liquid crystal display device using the same.

[0002]

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

The substrates 8 and 10 are made of glass transparent substrates 2 and
5, a pattern of transparent electrodes 3 and 6 made of an ITO film or the like is formed on one side, and the surfaces of the transparent electrodes 3 and 6 and the transparent substrates 2 and 5 are coated with alignment control films 4 and 7 made of a polyimide film or the like. Is obtained by The alignment control films 4 and 7 are subjected to an alignment control process by rubbing.

As a material for the spacer 9, generally,
Organic or inorganic materials are used. Examples of the spacer made of an inorganic material include those containing aluminum oxide, silicon dioxide, and the like (see, for example, JP-A-63-73225, JP-A-1-599974). But,
Conventional inorganic spacers have a high hardness, which damages the alignment film, and makes it difficult for the thickness change due to thermal expansion and shrinkage to follow the substrate, thereby causing poor gap unevenness.

Further, the spacer made of an organic material has an appropriate hardness that does not damage the alignment film, easily follows a change in thickness due to thermal expansion or thermal shrinkage, and further has a feature that spacer movement in a cell is small. There are mainly used polystyrene-based or benzoguanamine-based polymers (for example, JP-A-60-200288, JP-A-1-29331).
No. 6).

However, the liquid crystal display device manufactured using the above-described spacer has a problem that abnormal alignment of liquid crystal occurs around the liquid crystal spacer immediately after the cell is manufactured (hereinafter referred to as an “initial state”) and after a high voltage is applied. there were. In particular, a display device using a super twisted nematic (STN) liquid crystal has a problem that the tendency is remarkable and a uniform image cannot be maintained. The cause of the abnormal alignment is that the liquid crystal molecules are aligned around the spacer, and the magnitude of the abnormal alignment is estimated to depend on the degree of alignment of the liquid crystal molecules.

In order to solve such an abnormal orientation, the dielectric constant of the spacer (see Japanese Patent Application Laid-Open No. 6-67182)
Further, studies have been made to change the spacer surface composition (see JP-A-6-118421). However, if the composition of the polymer is largely changed in order to prevent abnormal alignment, there is a problem that the particles become fragile particles which do not have the necessary strength for the spacer and are broken when the liquid crystal display element is assembled.

Further, in a liquid crystal display device manufactured using a conventional spacer, there is a problem that the spacer moves due to vibration or the like at the time of injecting liquid crystal or transporting after manufacturing, and this moving portion causes display unevenness. there were. In particular, in recent years, with the spread of in-vehicle televisions, navigation systems, and the like, the use of liquid crystal display devices in places with severe vibration has increased, and thus spacers with higher adhesiveness have been required.

In response to such demands, it has been proposed that the surface of the particles is coated with an adhesion layer of a low melting point synthetic resin or wax having adhesion to the substrate (Japanese Patent Application Laid-Open No. Sho 63).
-94224). However, such a spacer has a problem that the adhesion layer is easily peeled off from the particle surface, and the peeled adhesion layer is mixed into the liquid crystal, thereby deteriorating the display performance of the liquid crystal display device.

In view of this, the inside of the particles must have sufficient strength, and only the surface of the particles has a composition suitable for preventing abnormal orientation.
So-called core-shell type spacers having a composition excellent in adhesion have been studied. However, there have been problems such as the inability to uniformly modify the entire surface and the necessity of a complicated multi-step operation for forming a shell layer.

[0011]

SUMMARY OF THE INVENTION In view of the above, the present invention has been developed, while maintaining the mechanical strength required for a spacer.
It is an object of the present invention to provide a core-shell type liquid crystal display element spacer in which a shell layer is provided with functions such as abnormal alignment prevention performance and adhesion performance, and a liquid crystal display element using the same.

[0012]

A spacer for a liquid crystal display element according to claim 1 (hereinafter referred to as "the present invention 1") is obtained by reacting an oxidizing agent with fine particles having a reducing group on the surface to form a surface of the fine particles. A spacer for a liquid crystal display element, which is formed by generating radicals and forming a polymerized layer on the surface of the fine particles starting from the radicals.

According to a second aspect of the present invention, there is provided the spacer for a liquid crystal display element according to the first aspect, wherein the oxidizing agent is a cerium salt.

According to a third aspect of the present invention, there is provided a spacer for a liquid crystal display element (hereinafter referred to as "the present invention 2"), wherein an oxidizing agent is reacted with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. A spacer for a liquid crystal display element, wherein a reactive graft polymer layer is formed on the surface of the fine particles by reacting a polymerizable monomer having an epoxy group with a radical as a starting point.

According to a fourth aspect of the present invention, there is provided a liquid crystal display element spacer (hereinafter referred to as "the present invention 3") which comprises reacting an oxidizing agent with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. Starting from a radical, by reacting a polymerizable monomer having an epoxy group and a polymerizable monomer having an ethylene glycol group, a reactive graft polymer layer is formed on the surface of the fine particles. For a liquid crystal display element.

The spacer for a liquid crystal display element according to the fifth aspect (hereinafter referred to as "the present invention 4") reacts an oxidizing agent with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. By reacting a polymerizable monomer having a long-chain alkyl group with a radical as a starting point, a graft polymer layer having a long-chain alkyl group is formed on the surface of the fine particles. It is.

The spacer for a liquid crystal display element according to claim 6 (hereinafter referred to as "the present invention 5") is obtained by reacting an oxidizing agent with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. By reacting a polymerizable monomer having a functional group with a radical as a starting point, a graft-polymerized layer having a functional group is formed on the surface of the fine particles, and further, a long-chain alkyl group is formed on the graft-polymerized layer having the functional group. A spacer for a liquid crystal display element, characterized by reacting a compound.

The spacer for a liquid crystal display element according to claim 7 (hereinafter referred to as "the present invention 6") is obtained by reacting an oxidizing agent with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. By reacting a polymerizable monomer having a functional group with a radical as a starting point, a graft polymer layer having a functional group is formed on the surface of the fine particles, and further, a polymerizable vinyl is formed on the graft polymer layer having the functional group. After introducing a group and / or an active group having a polymerization initiation ability, a polymerizable monomer having an epoxy group is reacted to form a graft polymer layer having an epoxy group on the surface of the graft polymer layer having the functional group. This is a spacer for a liquid crystal display element, which is characterized by being formed.

The spacer for a liquid crystal display element according to claim 8 (hereinafter referred to as "the present invention 7") is obtained by reacting an oxidizing agent with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. By reacting a polymerizable monomer having a functional group with a radical as a starting point, a graft polymer layer having a functional group is formed on the surface of the fine particles, and further, a polymerizable vinyl is formed on the graft polymer layer having the functional group. After introducing a group and / or an active group having a polymerization initiating ability, a polymerizable monomer having a long-chain alkyl group is reacted, whereby a graft having a long-chain alkyl group on the surface of the graft polymerization layer having the functional group is obtained. This is a spacer for a liquid crystal display element, which is formed by forming a polymer layer.

In a ninth aspect of the present invention, there is provided a liquid crystal display device (hereinafter referred to as "the present invention 8") in which an alignment film and a transparent electrode are arranged.
Claims 1, 2, 3, 4, 5, 6, 7
Or a liquid crystal display element opposed to the liquid crystal display element via a spacer for a liquid crystal display element according to claim 8, wherein liquid crystal is sealed between the glass substrates.

The spacer for a liquid crystal display element according to the first aspect of the present invention is a so-called core-shell type spacer in which a shell layer made of a polymerizable monomer is formed on the surface of the core fine particles.

Since the fine particles used in the present invention 1 function as core particles of a spacer for a liquid crystal display element, various performances are required in terms of particle diameter, particle diameter distribution, mechanical strength, and the like.

The fine particles preferably have a particle size of 1 to 10 μm. The particle size distribution of the fine particles is preferably 10% or less as a CV value obtained by dividing the standard deviation by the particle size. The mechanical strength of the fine particles preferably has a 10% K value of 250 to 1,000. If it is less than 250, the strength of the fine particles is not sufficient, so that the spacer is broken when assembling the liquid crystal display element and an appropriate gap does not appear. The alignment film is damaged, and display abnormalities occur.

Incidentally, the above 10% K value is defined as Table 6-5.
No. 03180, a micro compression tester (PCT
-200, manufactured by Shimadzu Corporation), the fine particles are compressed at a compression endurance of 0.27 g / sec and a maximum test load of 10 g on a smooth end surface of a diamond-made cylinder having a diameter of 50 μm. .

K = (3 / √2) ・ FS-3 / 2 ・ R-1 / 2 F: Overload value at 10% compressive deformation of fine particles (kg) S: Compressive displacement at 10% compressive deformation of fine particles (Mm) R: radius of fine particles (mm)

In the present invention 1, the fine particles have a reducing group on the surface. The reducing group is not particularly limited, and includes, for example, a hydroxyl group, a thiol group, an aldehyde group, a mercapto group, an amino group and the like.

The method for obtaining the above-mentioned fine particles having a reducing group on the surface is not particularly limited. For example, a method by a polymerization method such as emulsion polymerization, suspension polymerization, seed polymerization, dispersion polymerization, and dispersion seed polymerization; A method using an agent; a method using a surfactant, and the like. Further, inorganic fine particles having the above reducing group on the surface may be used.

As the method by the above polymerization method, for example,
A reducing group-containing monomer, and another monomer copolymerizable with the reducing group-containing monomer and / or a crosslinkable monomer copolymerizable with the reducing group-containing monomer. To obtain fine particles.

The reducing group of the reducing group-containing monomer is not particularly limited, and includes, for example, a hydroxyl group, a thiol group, an aldehyde group, a mercapto group, an amino group and the like. The reducing group-containing monomer is not particularly limited, and examples thereof include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, 2-methacryloyloxyethyl succinic acid, and 2-methacryloyloxy. (Meth) acrylic acid ester derivatives such as phthalic acid, mono [2 (meth) acryloyloxyethyl] acid phosphate, glycerol mono (meth) acrylate, glycerin di (meth) acrylate; styrene derivatives; vinyl esters; conjugated dienes, etc. Is mentioned.

The other monomer copolymerizable with the reducing group-containing monomer is not particularly limited. For example, styrene, α-methylstyrene, p-methyl Styrene derivatives such as styrene, p-chlorostyrene and chloromethylstyrene; vinyl esters such as vinyl chloride, vinyl acetate and vinyl propionate;
Unsaturated nitriles such as acrylonitrile; methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, ethylene glycol (meth) Acrylate, trifluoroethyl (meth)
(Meth) acrylate derivatives such as acrylate, pentafluoropropyl (meth) acrylate and cyclohexyl (meth) acrylate; and conjugated dienes such as butadiene and isoprene.

The crosslinking monomer copolymerizable with the above-mentioned reducing group-containing monomer is not particularly restricted but includes, for example, divinylbenzene, polyethylene glycol di (meth) acrylate, 1,6-hexanediol di (meth ) Acrylate, neopentyl glycol di (meth) acrylate,
Examples include trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolpropanetetra (meth) acrylate, diallyl phthalate and its isomers, triallyl isocyanurate and its derivatives, and the like.

Further, particles were prepared from radical polymerizable monomers such as γ-methacryloxypropyltrimethoxysilane having a reactive point in the side chain, and sufficient mechanical strength was obtained by a cross-linking reaction of the side chain portion. You may use something.

The reducing group-containing monomer, the other monomer, and the crosslinking monomer may be used alone.
Two or more kinds may be used in combination. However, from the viewpoint of the strength of the obtained spacer for a liquid crystal display element, it is desirable that the above-mentioned crosslinkable monomer accounts for 30% or more of all monomers.

The polymerization initiator used for copolymerizing the reducing group-containing monomer with the other monomer and / or the crosslinkable monomer is not particularly limited. Benzoyl oxide, lauroyl peroxide, orthochlorobenzoyl peroxide, orthomethoxybenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, t-butylperoxy-2-ethylhexanoate, di-t-butyl peroxide Organic peroxides such as;
Examples include azo compounds such as azobisisobutyronitrile, azobiscyclohexacarbonitrile, and azobis (2,4-dimethylvaleronitrile). Usually, the amount of the polymerization initiator to be used is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the total of the monomers.

The reducing group-containing monomer, the other monomer, the crosslinkable monomer and the polymerization initiator may be charged in their entirety first, or may be partially charged and then the remaining amount may be added stepwise. It may be supplied continuously or continuously. In the polymerization, the reaction system may be replaced with an inert gas such as nitrogen in order to prevent the polymerization from being inhibited by oxygen. At the time of polymerization, a dispersion stabilizer can be used as necessary. As the dispersion stabilizer, a polymer soluble in a medium, a nonionic or ionic surfactant, or the like can be appropriately used.

As a method using the above-mentioned polymer protective agent,
For example, a method of introducing a reducing group into the surface of the obtained fine particles by using a polymer protecting agent having a reducing group at the time of polymerizing the fine particles can be mentioned. The polymer protective agent is not particularly limited as long as it contains a reducing group. For example, polyvinyl alcohol, a polyvinyl alcohol derivative, cellulose, cellulose acetate, starch, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, poly (meta) ) Water-soluble polymers such as acrylic acid (sodium salt).

As a method of using the above-mentioned surfactant, for example, a reactive surfactant having a reducing group is used at the time of polymerizing fine particles to introduce a reducing group onto the surface of the obtained fine particles. Method and the like. The fine particles having a reducing group on the surface thereof are not limited to fine particles obtained by polymerizing a reducing group-containing monomer as described above,
Polymer fine particles such as benzoguanamine, nylon, polyester, and protein, and fine particles made of an inorganic compound having a reducing group on the surface may be used.

The fine particles may be colored fine particles for improving the contrast of the liquid crystal display device. The colored fine particles are not particularly limited, and include, for example,
Those obtained by treating the fine particles with carbon black, disperse dye, acid dye, basic dye, metal oxide, etc .; those formed by forming an organic film on the surface of the fine particles and dissolving or carbonizing at a high temperature, etc. Is mentioned.
When the material forming the fine particles has a color, it can be used as the colored fine particles without coloring.

The method for producing the above-mentioned colored fine particles is not particularly limited. For example, a composition obtained by dispersing a pigment in the above-mentioned reducing group-containing monomer or the like is mixed with an aqueous medium in the presence of the above-mentioned polymerization initiator. And a method of carrying out suspension polymerization in water.

The pigment used in producing the above colored fine particles is not particularly limited, and examples thereof include inorganic color pigments such as carbon black, graphite, iron black, chromium green, cobalt green, and chromium oxide; brilliant carmine BS, lake Azo or condensed azo organic coloring pigments such as Carmine FB, Brilliant Fast Scarlet, Lake Red 4R, Permanent Red R, Fast Red FGR, Toluidine Malon, Bisazo Yellow, First Yellow G, Bisazo Orange, Vulcan Orange, Pyrazolone Red, etc. Phthalocyanine-based organic coloring pigments such as phthalocyanine blue, fast ska blue, and phthalocyanine green; dye lake organic coloring pigments such as yellow lake, rose lake, violet lake, blue lake, and green lake; Futaron organic coloring pigments. These may be used alone or in combination of two or more.

The amount of the pigment added is 1 to 100 parts by weight of the total amount of the monomers used for producing the colored fine particles.
-180 parts by weight is preferred. If the amount is less than 1 part by weight, it becomes difficult to obtain a dark color, and if the amount exceeds 180 parts by weight, the mechanical strength of the obtained fine particles may not be obtained. More preferably, it is 3 to 160 parts by weight.

The method for uniformly dispersing the pigment in the reducing group-containing monomer and the like is not particularly limited.
Ball mill, bead mill, sand mill, attritor,
Examples thereof include a method using a sand grinder, a nanomizer, and the like.

When dispersing the pigment in the reducing group-containing monomer or the like, a dispersant may be added to improve the dispersibility of the pigment. The dispersant is not particularly limited and includes, for example, water-soluble polymers such as polyvinyl alcohol, starch, methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, and sodium polymethacrylate; barium sulfate, calcium sulfate, aluminum sulfate, calcium carbonate, calcium phosphate, Examples include talc, clay, diatomaceous earth, and metal oxide powder. The amount of the dispersant added is 0.01 to 100 parts by weight of the total amount of the monomers used for producing the colored fine particles.
-20 parts by weight are preferred.

In the present invention 1, an oxidizing agent is reacted with the fine particles having a reducing group on the surface to generate a radical on the surface of the fine particle, and the polymerizable monomer is reacted with the radical as a starting point. A polymer layer is formed on the surface of the fine particles.

The oxidizing agent is not particularly limited as long as it is capable of oxidizing the surface of the fine particles having the above-mentioned reducing group to generate radicals, and includes, for example, persulfate, cerium salt, persulfate, and the like. Hydrogen oxide, dimethylaniline,
Examples thereof include sodium periodate, potassium permanganate, and alkyl boron. Further, in order to increase the reaction rate of the polymerization system, an acid such as nitric acid or a salt may be added.

The concentration of the oxidizing agent is 0.0001 to 20 with respect to the total amount of the monomers used for producing the fine particles.
Molar% is preferred. When it is less than 0.0001 mol%,
When the rate of generation of the radical that becomes the graft polymerization start point on the fine particles decreases, and exceeds 20 mol%, the excess oxidizing agent reacts with the once generated radical to extinguish the start point, and the polymerization start point is reduced. Resulting in.

In the present invention 1, a cerium salt is suitably used as the oxidizing agent. The cerium salt is not particularly limited as long as it is tetravalent, and examples thereof include cerium sulfate, cerium nitrate, cerium ammonium sulfate, cerium ammonium pyrophosphate, and cerium iodide.

The polymerizable monomer is not particularly limited as long as it is a radical polymerizable monomer, and a polymer having a property desired to be imparted to the obtained liquid crystal display element spacer may be used. For example, when it is desired to impart hydrophilicity to the obtained liquid crystal display element spacer, hydroxyethyl (meth) acrylate, methoxypolyethylene glycol (meth)
A hydroxyl group such as acrylate; a monomer having an ethylene glycol component; When it is desired to impart hydrophobicity to the obtained spacer for a liquid crystal display element, (meth)
Alkyl (meth) acrylates such as butyl acrylate and stearyl (meth) acrylate; fluorine-containing (meth) acrylates such as trifluoroethyl (meth) acrylate and pentafluoropropyl (meth) acrylate; styrene, p-chlorostyrene and the like Styrene derivatives; glycidyl (meth) acrylate, (meth) acrylic acid, (meth) acrylamide, and the like having a reactive site. When it is desired to impart reactivity to the shell layer of the obtained spacer for a liquid crystal display element, a monomer having an epoxy group such as glycidyl (meth) acrylate and further a carboxylic acid group in addition to the above-mentioned hydroxyl group may be used. No. These may be used alone or in combination of two or more. Further, other polymerizable monomers copolymerizable with these polymerizable monomers may be used in combination.

A method for forming a polymer layer on the surface of the fine particles by generating a radical on the fine particles having the reducing group on the surface by using the cerium salt and further reacting the polymerizable monomer with the radical is described. For example, there is a method in which fine particles having a reducing group on the surface are dispersed in a solvent, and the polymerizable monomer and the cerium salt are added thereto, and a polymerization reaction is performed.

The reaction temperature during the polymerization reaction is not particularly limited, but is preferably 0 to 90 ° C. from the viewpoint of the stability of the cerium salt complex. More preferably, 10-5
0 ° C. Although the type of the solvent is not particularly limited, particularly when an alcohol is used, the cerium salt reacts with the alcohol which is a solvent, and particularly, the type of the alcohol (1,2-glycol>primary> secondary) > 3rd grade)
Therefore, a tertiary alcohol such as t-butyl alcohol is preferably used.

When the graft polymerization reaction is unlikely to occur with the cerium salt alone, or in order to increase the reaction rate of the polymerization reaction system, an appropriate acid is added to the polymerization system and the reaction is performed in an acidic region. Can be. The acid is not particularly limited, and examples thereof include nitric acid, sulfuric acid, hydrochloric acid, and formic acid. The acidic range of the polymerization reaction system is preferably pH 6 or lower, and more preferably lower. This is because when the pH is high, the cerium salt is less likely to dissociate.

Further, various reactions can be further carried out on the reactive sites on the fine particles on which the polymer layer obtained as described above is formed. The compound used in such a reaction is not particularly limited, and for example, a compound having an isocyanate group, an amino group, a carboxylic acid group, a carboxylic acid chloride, an epoxy group, a hydroxyl group, or the like can be used.

In the present invention 2, the oxidizing agent is reacted with the fine particles having a reducing group on the surface to generate a radical on the surface of the fine particle, and the polymerizable monomer having an epoxy group is reacted with the radical as a starting point. This is a spacer for a liquid crystal display element in which a reactive graft polymer layer is formed on the surface of the fine particles.

The fine particles having a reducing group on the surface used in the present invention 2 are the same as the fine particles having a reducing group on the surface described in detail in the description of the present invention 1.

The oxidizing agent used in the present invention 2 is the same as the oxidizing agent described in detail in the description of the present invention 1.

The polymerizable monomer having an epoxy group used in the present invention 2 is not particularly limited.
Glycidyl (meth) acrylate, glycidyl allyl ether, (meth) acrylate containing an alicyclic epoxy, and the like are included. These may be used alone or in combination of two or more.

Further, in addition to the polymerizable monomer having an epoxy group, another monomer copolymerizable with the polymerizable monomer having an epoxy group may be copolymerized. The other monomer is not particularly limited, and examples thereof include styrene, α-methylstyrene, p-methylstyrene, and p-methylstyrene.
Styrene derivatives such as chlorostyrene and chloromethylstyrene; vinyl esters such as vinyl acetate and vinyl propionate; unsaturated nitriles such as acrylonitrile; methyl (meth) acrylate, ethyl (meth) acrylate;
Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethylene glycol (meth) acrylate, trifluoroethyl (meth) acrylate, cyclohexyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate And (meth) acrylate derivatives such as hydroxybutyl (meth) acrylate, glycerol mono (meth) acrylate and glycerin di (meth) acrylate. These may be used alone,
More than one species may be used in combination.

In forming the reactive graft polymerization layer, the reaction temperature during the graft polymerization reaction is not particularly limited, but from the viewpoint of the reaction time and the viscosity of the system.
0-100 ° C is preferred.

The solvent used in the graft polymerization reaction is not particularly limited, but from the viewpoint of the solubility of the oxidizing agent,
Water alone or a mixture of water and a polar organic solvent is preferred. The polar organic solvent is not particularly limited and includes, for example, alcohols such as methanol, ethanol, propanol, i-propanol, butanol, t-butyl alcohol; ketones such as acetone and methyl ethyl ketone; ethers such as methyl ether; dimethyl Sulfoxide, dimethylformamide and the like. These may be used alone or in combination of two or more.

The spacer for a liquid crystal display element according to the second aspect of the present invention does not peel off the graft polymer layer from the surface of the fine particles and has high adhesion to the substrate. Therefore, in the liquid crystal display device using the liquid crystal display device spacer of the second aspect of the present invention, the liquid crystal is not contaminated, and there is no display unevenness due to the movement of the spacer.

The present invention 3 provides a method in which an oxidizing agent is reacted with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles. A spacer for a liquid crystal display element, wherein a reactive graft polymerization layer is formed on the surface of the fine particles by reacting a polymerizable monomer having a glycol group.

The fine particles having a reducing group on the surface used in the present invention 3 are the same as the fine particles having a reducing group on the surface described in detail in the description of the present invention 1. The oxidizing agent used in the present invention 3 is the same as the oxidizing agent described in detail in the description of the present invention 1.

The polymerizable monomer having an epoxy group used in the present invention 3 is the same as the polymerizable monomer having an epoxy group described in detail in the description of the present invention 2. The polymerizable monomer having an ethylene glycol group used in the present invention 3 is polyethylene glycol monomethacrylate, methoxy polyethylene glycol monomethacrylate, polyethylene glycol polypropylene glycol monomethacrylate, polyethylene glycol polytetramethylene glycol monomethacrylate, polyethylene glycol polypropylene glycol monomethacrylate. Octanol ether methacrylate and the like. These may be used alone or in combination of two or more.

Further, in addition to the polymerizable monomer having an epoxy and the polymerizable monomer having an ethylene glycol group, the polymerizable monomer having an epoxy and the polymerizable monomer having an ethylene glycol group can be used. Other copolymerizable monomers may be copolymerized. The other monomer is not particularly limited. For example, in the description of the present invention 2, those similar to those exemplified as the other monomer copolymerizable with the polymerizable monomer having epoxy can be used. No.

In forming the reactive graft polymerization layer, the reaction temperature during the graft polymerization reaction is not particularly limited, but from the viewpoint of the reaction time and the viscosity of the system,
0-100 ° C is preferred.

The solvent used in the graft polymerization reaction is not particularly limited, but from the viewpoint of the solubility of the oxidizing agent,
Water alone or a mixture of water and a polar organic solvent is preferred. The polar organic solvent is not particularly limited, and includes, for example, those similar to the polar organic solvents exemplified in the description of the present invention 2.

The spacer for a liquid crystal display element according to the third aspect of the present invention does not peel off the graft polymer layer from the surface of the fine particles and has high adhesion to the substrate. Therefore, in the liquid crystal display element using the liquid crystal display element spacer according to the third aspect of the invention, the liquid crystal is not contaminated, and there is no display unevenness due to the movement of the spacer.

The present invention 4 relates to a polymerizable monomer having a long-chain alkyl group starting from the radical by generating a radical on the surface of the fine particle by reacting the oxidizing agent with the fine particle having a reducing group on the surface. To form a graft polymerized layer having a long-chain alkyl group on the surface of the fine particles.

The fine particles having a reducing group on the surface used in the present invention 4 are the same as the fine particles having a reducing group on the surface described in detail in the description of the present invention 1. The oxidizing agent used in the present invention 4 is the same as the oxidizing agent described in detail in the description of the present invention 1.

The polymerizable monomer having a long-chain alkyl group used in the present invention 4 is not particularly limited.
A compound having 6 or more carbon atoms is preferable because it has an excellent effect of preventing abnormal orientation. The polymerizable monomer having such a long-chain alkyl group is not particularly limited. For example, hexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (Meth) acrylate, isodecyl (meth) acrylate, tridecyl (meth) acrylate, stearyl (meth) acrylate, behenyl (meth) acrylate, cetyl (meth) acrylate, nonylphenoxyethyl (meth) acrylate, lauryl polyoxyethylene (meth) Acrylate and the like. These may be used alone,
More than one species may be used in combination.

In addition to the polymerizable monomer having a long-chain alkyl group, another monomer copolymerizable with the polymerizable monomer having a long-chain alkyl group may be copolymerized. . The other monomer is not particularly limited. For example, in the description of the present invention 2, those similar to those exemplified as the other monomer copolymerizable with the polymerizable monomer having epoxy can be used. No.

In forming the graft polymerization layer having a long-chain alkyl group, the reaction temperature during the graft polymerization reaction is not particularly limited, but is preferably 30 to 100 ° C. from the viewpoint of the reaction time and the viscosity of the system.

The solvent used in the graft polymerization reaction is not particularly limited. However, from the viewpoint of the solubility of the oxidizing agent and the polymerizable monomer having a long-chain alkyl group, non-polar solvents such as hexane , Heptane, octane,
Benzene, toluene, etc., as polar solvents, for example,
Water, methanol, ethanol, propanol, i-propanol, butanol, alcohols such as t-butyl alcohol; ketones such as acetone and methyl ethyl ketone; ethers such as methyl ether; dimethyl sulfoxide, dimethylformamide and the like. These may be used alone or in combination of two or more.

The present invention 5 relates to a method of reacting a polymerizable monomer having a functional group with the radical as a starting point by reacting an oxidizing agent with fine particles having a reducing group on the surface to generate a radical on the surface of the fine particle. Thus, a graft polymer layer having a functional group is formed on the surface of the fine particles, and a spacer for a liquid crystal display element is obtained by reacting a long-chain alkyl compound with the graft polymer layer having the functional group.

The fine particles having a reducing group on the surface used in the present invention 5 are the same as the fine particles having a reducing group on the surface described in detail in the description of the present invention 1. The oxidizing agent used in the present invention 5 is the same as the oxidizing agent described in detail in the description of the present invention 1.

The polymerizable monomer having a functional group used in the present invention 5 is not particularly limited, and examples thereof include a carboxyl group, a hydroxyl group, an amino group, an amide group, an epoxy group, a sulfone group, a mercapto group, and an isocyanate group. A polymerizable monomer having a functional group of: hydrolysis, addition, condensation,
Examples include vinyl monomers that generate the above-described functional groups by means such as ring opening. Such monomers are not particularly limited, and include, for example, (meth) acrylic acid, 2-
(Meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl phthalic acid, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycerol (meth) acrylate alkylate, N-vinylformamide , N-vinylacetamide, (meth) acrylamide, glycidyl (meth) acrylate, γ-methacryloxypropyltrimethoxysilane, styrene p-sulfonate, 2-
(Acryloylamino) -2-methylpropanesulfonic acid, (meth) acryloyl isocyanate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, allyl alcohol, itaconic acid, crotonic acid, allyl glycidyl ether, dimethylaminoethyl (Meth) acrylate, dimethylaminopropyl (meth) acrylate and the like. These may be used alone or in combination of two or more. Further, in addition to the polymerizable monomer having a functional group, another monomer copolymerizable with the polymerizable monomer having the functional group may be copolymerized.

In forming the graft polymerization layer having the functional group, the reaction temperature during the graft polymerization reaction is not particularly limited, but is preferably 30 to 100 ° C. from the viewpoint of the reaction time and the viscosity of the system.

The solvent used in the graft polymerization reaction is not particularly limited, but from the viewpoint of the solubility of the oxidizing agent,
Water alone or a mixture of water and a polar organic solvent is preferred. The polar organic solvent is not particularly limited, and examples thereof include those similar to the polar organic solvents exemplified in the description of the present invention 2.

The spacer for a liquid crystal display device according to the fifth aspect of the present invention is obtained by further reacting a long-chain alkyl compound with the above-mentioned graft polymer layer having a functional group. The long-chain alkyl compound is not particularly limited. For example, long-chain alkyl carboxylic acids and halides and salts thereof, long-chain alkyl alcohols, long-chain alkyl sulfonic acids and halides and salts thereof, long-chain alkylamines, Long-chain alkylmethoxysilane, long-chain alkyl chloride, long-chain alkyl bromide, long-chain glycidyl, long-chain alkyl isocyanate, and the like. The alkyl group of the long-chain alkyl compound preferably has 6 to 30 carbon atoms. These may be used alone or in combination of two or more.

The method of reacting the above-mentioned long-chain alkyl compound with the above-mentioned graft-polymerized layer having a functional group varies depending on the type of the long-chain alkyl compound used. Examples thereof include methyl ethyl ketone, tetrahydrofuran, toluene, xylene, ethyl acetate and the like. In an organic solvent. Further, a catalyst such as an acid and an alkali can be used as required for the reaction.

According to the present invention 6, the fine particles having a reducing group on the surface are reacted with an oxidizing agent to generate radicals on the surface of the fine particles, and the polymerizable monomer having a functional group is reacted with the radical as a starting point. By forming a graft polymerization layer having a functional group on the surface of the fine particles, and further introducing a polymerizable vinyl group and / or an active group having a polymerization initiating ability into the graft polymerization layer having the functional group, A spacer for a liquid crystal display element, wherein a graft polymer layer having an epoxy group is formed on the surface of the graft polymer layer having a functional group by reacting a polymerizable monomer having an epoxy group.

The fine particles having a reducing group on the surface used in the sixth invention are the same as the fine particles having a reducing group on the surface described in detail in the description of the first invention. The oxidizing agent used in the present invention 6 is the same as the oxidizing agent described in detail in the description of the present invention 1.

The graft-polymerized layer having a functional group in the present invention 6 is the same as the graft-polymerized layer having a functional group described in detail in the description of the present invention 5.

In the present invention 6, a polymerizable vinyl group and / or an active group having a polymerization initiating ability are introduced into the graft polymerization layer having the above functional group. As a method of introducing a polymerizable vinyl group into the graft polymerization layer having the functional group,
For example, a method in which a compound having a functional group capable of reacting with the functional group of the graft polymerization layer having a functional group and a compound having a polymerizable vinyl group is reacted with the graft polymerization layer having the functional group, and the like can be mentioned. Such compounds are not particularly restricted but include, for example, (meth) acryloxyoxyethyl isocyanate, (meth) acryloyl isocyanate, (meth) acrylic acid, (meth) acrylic chloride, (meth) acrylamide, glycidyl (meth) acrylate And the like.

As a method for introducing an active group capable of initiating polymerization into the above-mentioned graft polymerization layer having a functional group, for example, a method having a functional group capable of reacting with a functional group of the above-mentioned graft polymerization layer having a functional group is used. A method of reacting an oxide, an azo compound, or the like with the graft polymerization layer having the above functional group is exemplified. Such compounds are not particularly restricted but include, for example, 4,4-azobis-4-cyano-valeric acid, 2,2-azobis-2- (2-imidazoline) propane and the like.

According to the sixth aspect of the present invention, after the active group having a polymerizable vinyl group and / or the active group having a polymerization initiation ability is introduced into the graft polymerization layer having the functional group, the polymerization group having an epoxy group is further added. The reactive monomer is reacted.

The polymerizable monomer having an epoxy group used in the present invention 6 is the same as the polymerizable monomer having an epoxy group described in detail in the description of the present invention 2.

Further, in addition to the polymerizable monomer having an epoxy group, another monomer copolymerizable with the polymerizable monomer having an epoxy group may be copolymerized. The other monomer is not particularly limited, and may be, for example, the same as those exemplified as the other monomer copolymerizable with the polymerizable monomer having an epoxy group in the description of the present invention 2. Is mentioned.

The spacer for a liquid crystal display element according to the sixth aspect of the present invention does not peel off the graft polymer layer from the surface of the fine particles and has high adhesion to the substrate. Therefore, in the liquid crystal display device using the liquid crystal display device spacer of the sixth invention, the liquid crystal is not contaminated, and there is no display unevenness due to the movement of the spacer.

In the present invention 7, a fine particle having a reducing group on its surface is reacted with an oxidizing agent to generate a radical on the surface of the fine particle, and a polymerizable monomer having a functional group is reacted with the radical as a starting point. By forming a graft polymerization layer having a functional group on the surface of the fine particles, and further introducing a polymerizable vinyl group and / or an active group having a polymerization initiating ability into the graft polymerization layer having the functional group, By reacting a polymerizable monomer having a long-chain alkyl group to form a graft-polymerized layer having a long-chain alkyl group on the surface of the graft-polymerized layer having the functional group, for a liquid crystal display element. It is a spacer.

The fine particles having a reducing group on the surface used in the present invention 7 are the same as the fine particles having a reducing group on the surface described in detail in the description of the present invention 1. The oxidizing agent used in the present invention 7 is the same as the oxidizing agent described in detail in the description of the present invention 1.

The graft-polymerized layer having a functional group in the present invention 7 is the same as the graft-polymerized layer having a functional group described in the description of the present invention 5 in detail.

In the present invention 7, a polymerizable vinyl group and / or an active group capable of initiating polymerization are introduced into the graft polymerization layer having the functional group. The method of introducing a polymerizable vinyl group into the graft polymerization layer having a functional group is the same as the method described in detail in the description of the spacer for a liquid crystal display element of the sixth invention.

The method for introducing an active group capable of initiating polymerization into the graft polymerization layer having a functional group is the same as the method described in detail in the description of the present invention 6.

In the present invention 7, after the active group having a polymerizable vinyl group and / or the active group having a polymerization initiating ability is introduced into the graft polymerization layer having the functional group, a long-chain alkyl group is further added. The polymerizable monomer having is reacted.

The polymerizable monomer having a long-chain alkyl group used in the present invention 7 is the same as the polymerizable monomer having a long-chain alkyl group described in detail in the description of the present invention 4.

In addition to the polymerizable monomer having a long-chain alkyl group, another monomer copolymerizable with the polymerizable monomer having a long-chain alkyl group may be copolymerized. . The other monomer is not particularly limited. For example, in the description of the spacer for a liquid crystal display element of the second embodiment, the other monomer copolymerizable with the polymerizable monomer having an epoxy group is exemplified. And the like.

The present invention 8 relates to a liquid crystal display element spacer according to the present invention 1, a liquid crystal display element spacer according to the present invention 2, and a liquid crystal display element spacer according to the present invention 3.
, The liquid crystal display element spacer of the present invention 4, the liquid crystal display element spacer of the present invention 5, the liquid crystal display element spacer of the present invention 6, or the liquid crystal display element spacer of the present invention 7 And a liquid crystal display element in which liquid crystal is sealed between the glass substrates. Examples of the liquid crystal display element include those shown in FIG.

[0099]

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

Example 1 (Preparation of fine particles having a reducing group on the surface) A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was homogenized. The particle size was adjusted by stirring.
Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream while stirring,
The reaction was performed for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5, and the following operation was performed using the fine particles as seed particles.

(Preparation of Fine Particles Having Polymerized Layer) In a separable flask, 250 parts by weight of ion-exchanged water, 5 parts by weight of methyl methacrylate and 5 parts by weight of seed particles obtained by the above operation were added, and sufficiently dispersed by a sonicator. After that, stirring was performed uniformly. Introduce nitrogen gas into the system
Stirring was continued at 0 ° C. for 3 hours. To this, 12.5 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 1N aqueous nitric acid solution was added and reacted for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The fine particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure with a vacuum dryer.

Using the fine particles, evaluation of the mechanical strength of the spacer and analysis of the surface composition were performed by the following methods. result,
The mechanical strength (10% K value) was 420 kgf / mm2, and as a result of TOF-SIMS analysis, methyl methacrylate was present on the spacer surface.

(Evaluation of Mechanical Strength) Micro Compression Tester (PC
Using a T-200 (manufactured by Shimadzu Corporation), the obtained fine particles were subjected to a compression test at a compression rate of 0.27 g / sec and a maximum test load of 10 g using a diamond-made cylindrical smooth end face having a diameter of 50 μm. The K value was determined from this. K = (3 / √2) · FS · 3/2 · R-1 / 2 F: Overload value at 10% compressive deformation of fine particles (kg) S: Compressive displacement at 10% compressive deformation of fine particles (mm) R: radius of fine particles (mm)

(Surface Composition Analysis) Analysis was performed by a time-of-flight secondary ion mass spectrometer (TOF-SIMS). According to this apparatus, the area of 0.2 μm square is reduced to 0.0 mm in the thickness direction.
Only the polar surface of about 1 μm can be analyzed, and the ratio of the polymer constituting the surface of each composition can be calculated from the count number of the detected mass spectrum.

Example 2 In the synthesis of fine particles having a polymerized layer, lauryl acrylate 8 was used in place of methyl methacrylate as a polymerizable monomer.
The same operation as in Example 1 was performed except that parts by weight were used. The spacer was evaluated using the fine particles. As a result, the mechanical strength (10% K value) was 420 kgf / mm2, and as a result of TOF-SIMS analysis, lauryl acrylate was present on the spacer surface.

Example 3 The same operation as in Example 1 was carried out except that 5 parts by weight of hydroxy methacrylate was used instead of methyl methacrylate as a polymerizable monomer for synthesizing fine particles having a polymerized layer. As a result of TOF-SIMS analysis, hydroxyethyl methacrylate was present on the spacer surface.

Further, 2 parts by weight of the obtained fine particles and 30 parts by weight of toluene were stirred at 60 ° C. in a separable flask, and then added with 0.04 parts of dibutyltin dilaurate.
Parts by weight were dissolved in 4 parts by weight of toluene and added. To this was added 5 parts by weight of propyl isocyanate dissolved in 5 parts by weight of toluene and reacted at 80 ° C. for 6 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The fine particles were sufficiently washed with acetone, and dried under reduced pressure with a vacuum drier.

The spacer was evaluated using the fine particles. As a result, the mechanical strength (10% K value) was 420 kgf / m.
m2, and as a result of TOF-SIMS analysis, a propyl group was present on the spacer surface.

Example 4 60 parts by weight of tetramethylol methane triacrylate
20 parts by weight of divinylbenzene and 20 parts by weight of acrylonitrile were uniformly mixed, 12 parts by weight of carbon black was added thereto, and the carbon black was uniformly dispersed over 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide was uniformly mixed with the monomer mixture, and further added to 850 parts by weight of a 3% aqueous solution of polyvinyl alcohol. After well-stirring and particle size adjustment, the temperature was raised to 80 ° C. under a nitrogen stream, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm.
m, CV value = 5, and using these fine particles as seed particles, a production operation of fine particles having a polymerized layer was performed in the same manner as in Example 1.

The spacer was evaluated using the fine particles. As a result, the mechanical strength (10% K value) was 420 kgf / m.
m2, and as a result of TOF-SIMS analysis, methyl methacrylate was present on the spacer surface.

Example 5 Surfactant Hitenol N-08 (Daiichi Kogyo Seiyaku Co., Ltd.)
A mixture of 80 parts by weight of divinylbenzene, 20 parts by weight of hydroxyethyl methacrylate, and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of the above, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5. Using these fine particles as seed particles, a production operation of fine particles having a polymerized layer was performed in the same manner as in Example 2.

The evaluation of the spacer was performed using the fine particles. As a result, the mechanical strength (10% K value) was 400 kgf / m.
m2, and as a result of TOF-SIMS analysis, lauryl acrylate was present on the spacer surface.

Example 6 A separable flask was charged with 60 parts by weight of a 10% hydrogen peroxide solution, 70 parts by weight of acetone and 5 parts by weight of the seed particles obtained in Example 1 and stirred for 30 minutes. 50 parts by weight and 20 parts by weight of iron sulfate heptahydrate.
Stirred at C for 3 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The fine particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure with a vacuum dryer.

The evaluation of the spacer was performed using the fine particles. As a result, the mechanical strength (10% K value) was 420 kgf / m.
m2, and as a result of TOF-SIMS analysis, methyl methacrylate was present on the spacer surface.

Comparative Example 1 Seed particles were prepared using the surfactant Hitenol N-08 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) instead of polyvinyl alcohol, and then fine particles having a polymerized layer were produced in the same manner as in Example 1. Was prepared. The spacer was evaluated using the fine particles. As a result, the mechanical strength (10% K value) was 420 kgf.
/ Mm 2, and as a result of TOF-SIMS analysis, divinylbenzene was present on the spacer surface, and the presence of methyl methacrylate could not be confirmed.

Comparative Example 2 200 parts by weight of ion-exchanged water, 5 parts by weight of methyl methacrylate and 5 parts by weight of the seed particles obtained in Example 1 were added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly dispersed. Stirring was performed. Introduce nitrogen gas into the system,
Stirring was continued at 30 ° C. for 3 hours. To this was added 0.1 parts by weight of benzoyl peroxide and reacted for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The fine particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure with a vacuum dryer. The spacer was evaluated using the fine particles. As a result, the mechanical strength (10% K value) was 420 kgf / mm2, and as a result of TOF-SIMS analysis, divinylbenzene was present on the spacer surface, and the presence of methyl methacrylate could not be confirmed.

Comparative Example 3 The same operation as in Example 1 was performed except that 20 parts by weight of divinylbenzene and 80 parts by weight of lauryl acrylate were used for synthesizing fine particles having a reducing group on the surface. The spacer was evaluated using the fine particles. As a result, the obtained fine particles were very fragile, and the mechanical strength (10% K value) could not be measured. As a result of TOF-SIMS analysis, lauryl acrylate and divinylbenzene were present on the spacer surface.

Example 7 Seed particles were produced in the same manner as in Example 1 except that hydroxyethyl cellulose was used in place of polyvinyl alcohol, and then fine particles having a polymerized layer were produced in the same manner as in Example 1. The spacer was evaluated using the fine particles.
As a result, the mechanical strength (10% K value) was 420 kgf / mm2.
As a result of TOF-SIMS analysis, methyl methacrylate was present on the spacer surface.

Example 8 (Preparation of fine particles having a reducing group on the surface) A mixed solution of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was homogenized. The particle size was adjusted by stirring.
Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream while stirring,
The reaction was performed for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5. When surface analysis was performed by TOF-SIMS,
OH groups derived from polyvinyl alcohol were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Reactive Graft Polymerization Layer) Into a separable flask, 95 parts by weight of ion-exchanged water, 5 parts by weight of glycidyl methacrylate, 5 parts by weight of methyl methacrylate and 5 parts by weight of seed particles obtained by the above operation were added. After sufficiently dispersing with a sonicator, the mixture was uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. To this, 10 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution was added and reacted for 5 hours.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier. About the obtained particles,
The dissolution test and evaluation of the adhesion to the liquid crystal were performed by the following methods. The results are shown in Table 1.

(Dissolution Test for Liquid Crystal) 0.1 g of the obtained particles was weighed with a liquid crystal (ZLI-4720-00, manufactured by Merck Ltd.).
0) Dispersed in 2 mL and left at 80 ° C. for 200 hours. Thereafter, the liquid crystal was collected, and the purity of the liquid crystal was examined by gas chromatography.

(Adhesion Test) The obtained particles were coated with a polyimide alignment film and cured to form a glass substrate (manufactured by Nissan Chemical Industries, Ltd .: Sunever 150), and then spin-coated at 230 ° C. × 1.
Time firing). This substrate was heated at 120 ° C. for 10 minutes,
After heating under a temperature condition of 150 ° C. × 1 hour, an air blow test was performed. In the air blow test, after measuring the number of particles in a predetermined visual field with an optical microscope, an air gun (3 kgf /
(cm 2), air was blown from a distance of 10 cm from the substrate for 5 seconds, and the number of remaining particles was measured again.

Example 9 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 8 was performed. (Formation of Reactive Graft Polymerization Layer) The same operation as in Example 8 was performed except that hydroxyethyl methacrylate was used instead of methyl methacrylate. About the obtained particle, the dissolution test with respect to the liquid crystal and the evaluation of the adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

Example 10 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 8 was performed. (Formation of Reactive Graft Polymerization Layer) The same operation as in Example 8 was carried out except that glycidyl allyl ether was used instead of glycidyl methacrylate and hydroxyethyl methacrylate was used instead of methyl methacrylate. About the obtained particle, the dissolution test with respect to the liquid crystal and the evaluation of the adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

Example 11 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 8 was performed.

(Formation of Reactive Graft Polymerization Layer) In a separable flask, 100 parts by weight of ion-exchanged water, 30 parts by weight of isopropyl alcohol, glycidyl methacrylate 4
After adding 5 parts by weight and 5 parts by weight of the seed particles obtained by the above operation and sufficiently dispersing with a sonicator, the mixture was uniformly stirred. Further, 0.15 parts by weight of ammonium persulfate and 0.003 parts by weight of sodium bisulfite were added,
The mixture was sufficiently dissolved and stirred. The system was once depressurized with a pump, and then nitrogen gas was introduced and stirring was continued for 30 minutes.
The temperature was raised to 50 ° C., and the reaction was continued for 2 hours. Two hours later, the system was cooled, and the reaction was stopped by adding 100 parts by weight of tetrahydrofuran and a small amount of hydroquinone.

After completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran, and dried under reduced pressure with a vacuum drier. About the obtained particle, the dissolution test with respect to the liquid crystal and the evaluation of the adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

Example 12 (Preparation of fine particles having a reducing group on the surface) 50 parts by weight of trimethylolpropane triacrylate, 40 parts by weight of divinylbenzene, and 10 parts by weight of acrylonitrile were uniformly mixed, and 12 parts by weight of carbon black was added thereto. Was added and stirred for 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide were uniformly mixed with the monomer mixture, and further mixed with a 3% aqueous solution of polyvinyl alcohol 85%.
0 parts by weight. After sufficient stirring and particle size adjustment, the mixture was heated to 80 ° C. under a nitrogen stream and reacted for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm, a CV value of 5.0, and were black. When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface.
The following operation was performed using these fine particles as seed particles.

(Formation of Reactive Graft Polymerization Layer) Example 8
The same operation as described above was performed. About the obtained particle, the dissolution test with respect to the liquid crystal and the evaluation of the adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

Example 13 (Preparation of fine particles having a reducing group on the surface) In 800 parts by weight of a 3% aqueous solution of surfactant Hytenol N-08 (manufactured by Daiichi Kogyo Seiyaku), 80 parts by weight of divinylbenzene, A mixture of 20 parts by weight of ethyl methacrylate and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The resulting fine particles had an average particle size of 6.0 μm and a CV
Value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Reactive Graft Polymerization Layer) Example 8
The same operation as described above was performed. About the obtained particle, the dissolution test with respect to the liquid crystal and the evaluation of the adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

Comparative Example 4 A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was stirred with a homogenizer to adjust the particle size. 80 ° C under a nitrogen stream with stirring
And the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm,
V value was 5.0. With respect to the obtained fine particles, a dissolution test on liquid crystals and evaluation of adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

Comparative Example 5 To 80 g of the fine particles obtained in Comparative Example 4, 5 g of 0.2 μm methyl methacrylate-glycidyl methacrylate copolymer particles were mixed and adsorbed in an alcohol solvent.
This was coated by heat treatment to synthesize particles having a reaction layer. About the obtained particle, the dissolution test with respect to the liquid crystal and the evaluation of the adhesion were performed in the same manner as in Example 8. The results are shown in Table 1.

[0135]

[Table 1]

Example 14 (Preparation of fine particles having a reducing group on the surface) A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was homogenized. The particle size was adjusted by stirring.
Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream while stirring,
The reaction was performed for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5. When surface analysis was performed by TOF-SIMS,
OH groups derived from polyvinyl alcohol were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Reactive Graft Polymerization Layer) In a separable flask, 95 parts by weight of ion-exchanged water, 5 parts by weight of glycidyl methacrylate, methoxypolyethylene glycol monomethacrylate (number of ethylene glycol units = 9) (manufactured by NOF Corporation: PMA) -400) 5 parts by weight and 5 parts by weight of the seed particles obtained by the above operation were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. To this, 10 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution was added and reacted for 5 hours.

After completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier. About the obtained particles,
The mechanical strength was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Example 15 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 14 was performed.

(Formation of Reactive Graft Polymerization Layer) Methoxy polyethylene glycol monomethacrylate (number of ethylene glycol units = 9) (manufactured by NOF Corporation: PMA-
400) instead of methoxypolyethylene glycol monomethacrylate (number of ethylene glycol units =
9) The same operation as in Example 14 was performed except that (manufactured by NOF Corporation: PMA-4000) was used. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and adhesion of liquid crystal were evaluated in Example 8.
Was performed in the same manner as described above. The results are shown in Table 2.

Example 16 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 14 was performed.

(Formation of Reactive Graft Polymerization Layer) The same operation as in Example 14 was performed except that glycidyl allyl ether was used instead of glycidyl methacrylate. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Example 17 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 14 was performed.

(Formation of Reactive Graft Polymerization Layer) In a separable flask, 100 parts by weight of ion-exchanged water, 30 parts by weight of isopropyl alcohol, glycidyl methacrylate 4
0 parts by weight, 10 parts by weight of methoxypolyethylene glycol monomethacrylate (the number of ethylene glycol units = 9) (manufactured by NOF Corporation: PMA-400) and 5 parts by weight of seed particles obtained by the above operation were added, and the mixture was sufficiently dispersed with a sonicator. After that, stirring was performed uniformly. Further, 0.15 parts by weight of ammonium persulfate and 0.003 parts by weight of sodium bisulfite were added, sufficiently dissolved, and stirred. The system was once depressurized with a pump, and then nitrogen gas was introduced and stirring was continued for 30 minutes. The temperature was raised to 50 ° C., and the reaction was continued for 2 hours. Two hours later, the system was cooled, and the reaction was stopped by adding 100 parts by weight of tetrahydrofuran and a small amount of hydroquinone.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran, and dried under reduced pressure with a vacuum drier. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Example 18 (Preparation of fine particles having a reducing group on the surface) 50 parts by weight of trimethylolpropane triacrylate, 40 parts by weight of divinylbenzene, and 10 parts by weight of acrylonitrile were uniformly mixed, and 12 parts by weight of carbon black was added thereto. Was added and stirred for 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide were uniformly mixed with the monomer mixture, and further mixed with a 3% aqueous solution of polyvinyl alcohol 85%.
0 parts by weight. After sufficient stirring and particle size adjustment, the mixture was heated to 80 ° C. under a nitrogen stream and reacted for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm, a CV value of 5.0, and were black. When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface.
The following operation was performed using these fine particles as seed particles.

(Formation of Reactive Graft Polymerization Layer) Example 1
The same operation as in No. 4 was performed. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Example 19 (Preparation of fine particles having a reducing group on the surface) In 800 parts by weight of a 3% aqueous solution of surfactant Hytenol N-08 (manufactured by Daiichi Kogyo Seiyaku), 80 parts by weight of divinylbenzene, A mixture of 20 parts by weight of ethyl methacrylate and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The resulting fine particles had an average particle size of 6.0 μm and a CV
Value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Reactive Graft Polymerization Layer) Example 1
The same operation as in No. 4 was performed. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Comparative Example 6 A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was stirred with a homogenizer to adjust the particle size. 80 ° C under a nitrogen stream with stirring
And the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm,
V value was 5.0. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Comparative Example 7 0.2 μm of methoxypolyethylene glycol monomethacrylate (the number of ethylene glycol units = 9) (manufactured by NOF Corporation: PM) was added to 80 g of the fine particles obtained in Comparative Example 6.
A-400) -Glycidyl methacrylate copolymer particles 5
g was adsorbed by mixing in an alcohol solvent. This was coated by heat treatment to synthesize particles having a reaction layer. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

Comparative Example 8 Surfactant Hytenol N-08 (Daiichi Kogyo Seiyaku)
Glycidyl methacrylate 50 parts by weight, methoxypolyethylene glycol monomethacrylate (number of ethylene glycol units = 9) in 800 parts by weight of a 3% aqueous solution of
A mixture of 50 parts by weight (manufactured by NOF Corporation: PMA-400) and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm.
m, CV value = 5.0. About the obtained particles,
The mechanical strength was evaluated in the same manner as in Example 1, and the dissolution test and the adhesion of the liquid crystal were evaluated in the same manner as in Example 8. The results are shown in Table 2.

[0153]

[Table 2]

Example 20 (Preparation of fine particles having a reducing group) Divinylbenzene 10 was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol.
A mixture of 0 parts by weight and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5.
When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft-Polymerized Layer Having Long-Chain Alkyl Group) A separable flask was charged with 95 parts by weight of ion-exchanged water, 10 parts by weight of lauryl acrylate and 5 parts by weight of seed particles obtained by the above operation. After sufficiently dispersing the mixture, the mixture was uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. To this, 10 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 1N aqueous nitric acid solution was added and reacted for 5 hours.

After completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier. About the obtained particles,
The mechanical strength was evaluated in the same manner as in Example 1, and the orientation state was evaluated by the following method. The results are shown in Table 3.

(Evaluation of orientation state) The obtained particles were sprayed, and the substrate size was 50 × 50 mm and the cell gap was 6.0 μm.
m STN type liquid crystal display devices were manufactured, and the alignment state of the liquid crystal was evaluated as follows. Observation and comparison of the initial state of the liquid crystal display device (state in which AC 3 V is applied to the device after cell production) and the voltage applied state (state in which a voltage of 400 Hz, AC 50 V is applied to the device for 5 seconds, and then AC 3 V is applied) using a polarizing microscope. However, when light leakage occurred around the particles after voltage application, it was evaluated that abnormal orientation occurred.

Example 21 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 20 was performed. (Formation of Graft Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 20 was performed, except that octyl methacrylate was used instead of lauryl acrylate.
The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 20. The results are shown in Table 3.

Example 22 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 20 was performed.

(Formation of Graft Polymerization Layer Having Long-Chain Alkyl Group) In a separable flask, 50 parts by weight of ion-exchanged water, 80 parts by weight of isopropyl alcohol, 45 parts by weight of stearyl methacrylate, and 5 parts by weight of seed particles obtained by the above operation The mixture was added and dispersed sufficiently by a sonicator, and then uniformly stirred. Further, 0.15 parts by weight of ammonium persulfate and 0.003 parts by weight of sodium bisulfite were added, sufficiently dissolved, and stirred. The system was once depressurized with a pump, and then nitrogen gas was introduced and stirring was continued for 30 minutes. The temperature was raised to 50 ° C., and the reaction was continued for 2 hours. After 2 hours, the system was cooled and tetrahydrofuran 1
The reaction was stopped by adding 00 parts by weight and a small amount of hydroquinone.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran, and dried under reduced pressure with a vacuum drier. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 20. The results are shown in Table 3.

Example 23 (Preparation of fine particles having a reducing group on the surface) Trimethylolpropane triacrylate (50 parts by weight), divinylbenzene (40 parts by weight) and acrylonitrile (10 parts by weight) were uniformly mixed, and carbon black (12 parts by weight) was added thereto. Was added and stirred for 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide were uniformly mixed with the monomer mixture, and further mixed with a 3% aqueous solution of polyvinyl alcohol 85%.
0 parts by weight. After sufficient stirring and particle size adjustment, the mixture was heated to 80 ° C. under a nitrogen stream and reacted for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm, a CV value of 5.0, and were black. When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface.
The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 20 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 20. The results are shown in Table 3.

Example 24 (Preparation of fine particles having a reducing group on the surface) In 800 parts by weight of a 3% aqueous solution of surfactant Hytenol N-08 (manufactured by Daiichi Kogyo Seiyaku), 80 parts by weight of divinylbenzene, A mixture of 20 parts by weight of ethyl methacrylate and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The resulting fine particles had an average particle size of 6.0 μm and a CV
Value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft-Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 20 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 20. The results are shown in Table 3.

Comparative Example 9 A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was stirred with a homogenizer to adjust the particle size. 80 ° C under a nitrogen stream with stirring
And the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm,
V value = 5. About the obtained fine particles, Example 2
The mechanical strength and the orientation state were evaluated in the same manner as in the case of 0. The results are shown in Table 3.

Comparative Example 10 Surfactant Hitenol N-08 (Daiichi Kogyo Seiyaku)
A mixture of 20 parts by weight of divinylbenzene, 80 parts by weight of stearyl methacrylate and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of the above, and the particle size was adjusted by stirring with a homogenizer. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles have an average particle size =
6.0 μm, CV value = 5. The obtained fine particles were evaluated for mechanical strength and orientation state in the same manner as in Example 20. The results are shown in Table 3.

Comparative Example 11 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 20 was performed. (Formation of Graft Polymerized Layer) The same operation as in Example 20 was performed except that 10 parts by weight of methyl methacrylate was used instead of lauryl acrylate. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 20. The results are shown in Table 3.

[0169]

[Table 3]

Example 25 (Preparation of fine particles having a reducing group on the surface) A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was homogenized. The particle size was adjusted by stirring.
Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream while stirring,
The reaction was performed for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5. When surface analysis was performed by TOF-SIMS,
OH groups derived from polyvinyl alcohol were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
95 parts by weight of ion-exchanged water, 10 parts by weight of hydroxyethyl methacrylate, and 5 parts by weight of the seed particles obtained by the above operation were added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. To this, 10 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 1N aqueous nitric acid solution was added and reacted for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Reaction of Long-Chain Alkyl Compound) To a separable flask, 80 parts by weight of toluene and 5 parts by weight of the particles obtained by the above operation were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Next, 0.05 parts by weight of di-n-butyltin dilaurate was added, and after sufficient stirring, a solution of 5 parts by weight of stearyl isocyanate dissolved in 10 parts by weight of toluene was added dropwise. 60 ℃ system
And the reaction was continued for 5 hours.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration through a 3 μm membrane filter. The particles were sufficiently washed with toluene and acetone, and dried under reduced pressure with a vacuum drier. The mechanical strength of the obtained particles was evaluated in the same manner as in Example 1, and the orientation state was evaluated in the same manner as in Example 20. The results are shown in Table 4.

Example 26 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 25 was performed. (Formation of Graft Polymer Layer Having Functional Group) The same operation as in Example 25 was performed.

(Reaction of Long-Chain Alkyl Compound) In a separable flask, 150 parts by weight of tetrahydrohyran, 20 parts by weight of triethylamine and 5 parts by weight of the particles obtained by the above operation were added, and the mixture was sufficiently dispersed by a sonicator. Was stirred. Next, a solution in which 10 parts by weight of stearic acid chloride was dissolved in 20 parts by weight of tetrahydrofuran was dropped into the system. The system was kept at 30 ° C. and stirred for 3 hours to continue the reaction.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran and methanol, and dried under reduced pressure with a vacuum drier. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 25.

Example 27 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 25 was performed. (Formation of Graft Polymerized Layer Having Functional Group) The same operation as in Example 25 was performed except that 10 parts by weight of methacrylic acid was used instead of hydroxyethyl methacrylate.

(Reaction of long-chain alkyl compound) In a separable flask, 60 parts by weight of toluene and triethylamine 1
Then, 10 parts by weight of the particles obtained by the above operation and 10 parts by weight of the particles obtained above were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Next, a solution of 10 parts by weight of stearyl glycidyl dissolved in 10 parts by weight of toluene was dropped into the system. The reaction was continued by stirring the system at reflux temperature for 6 hours.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration through a 3 μm membrane filter. The particles were sufficiently washed with toluene and methanol, and dried under reduced pressure with a vacuum drier. About the obtained particles,
The mechanical strength and the orientation state were evaluated in the same manner as in Example 25. The results are shown in Table 4.

Example 28 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 25 was performed.

(Formation of Graft Polymerized Layer Having Functional Group)
100 parts by weight of ion-exchanged water, 30 parts by weight of isopropyl alcohol, 45 parts by weight of glycidyl methacrylate and 5 parts by weight of the seed particles obtained by the above operation are added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly stirred. Was done. In addition, ammonium persulfate 0.1.
15 parts by weight and 0.003 parts by weight of sodium bisulfite were added, sufficiently dissolved, and stirred. The system was once depressurized with a pump, and then nitrogen gas was introduced and stirring was continued for 30 minutes. The temperature was raised to 50 ° C., and the reaction was continued for 2 hours.
Two hours later, the system was cooled, and the reaction was stopped by adding 100 parts by weight of tetrahydrofuran and a small amount of hydroquinone.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran, and dried under reduced pressure with a vacuum drier.

(Reaction of long-chain alkyl compound) A separable flask was charged with 60 parts by weight of toluene and 1 part of triethylamine.
Then, 10 parts by weight of the particles obtained by the above operation and 10 parts by weight of the particles obtained above were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Next, a solution in which 10 parts by weight of stearylamine was dissolved in 10 parts by weight of toluene was dropped into the system. The reaction was continued by stirring the system at reflux temperature for 6 hours.

After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration through a 3 μm membrane filter. The particles were sufficiently washed with toluene and methanol, and dried under reduced pressure with a vacuum drier. About the obtained particles,
The mechanical strength and the orientation state were evaluated in the same manner as in Example 25. The results are shown in Table 4.

Example 29 (Preparation of fine particles having a reducing group on the surface) Trimethylolpropane triacrylate (50 parts by weight), divinylbenzene (40 parts by weight) and acrylonitrile (10 parts by weight) were uniformly mixed, and carbon black (12 parts by weight) was added thereto. Was added and stirred for 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide were uniformly mixed with the monomer mixture, and further mixed with a 3% aqueous solution of polyvinyl alcohol 85%.
0 parts by weight. After sufficient stirring and particle size adjustment, the mixture was heated to 80 ° C. under a nitrogen stream and reacted for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm, a CV value of 5.0, and were black. When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface.
The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 25 was performed. (Reaction of long-chain alkyl compound) The same operation as in Example 25 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 25. The results are shown in Table 4.

Example 30 (Preparation of fine particles having a reducing group on the surface) In 800 parts by weight of a 3% aqueous solution of surfactant Hytenol N-08 (manufactured by Daiichi Kogyo Seiyaku), 80 parts by weight of divinylbenzene, A mixture of 20 parts by weight of ethyl methacrylate and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The resulting fine particles had an average particle size of 6.0 μm and a CV
Value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 25 was performed. (Reaction of long-chain alkyl compound) The same operation as in Example 25 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 25. The results are shown in Table 4.

Example 31 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 25 was performed, except that hydroxypropyl cellulose was used instead of polyvinyl alcohol. T
When surface analysis was performed by OF-SIMS, OH groups derived from hydroxypropyl cellulose were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 25 was performed. (Reaction of long-chain alkyl compound) The same operation as in Example 25 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 25. The results are shown in Table 4.

Comparative Example 12 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 25 was performed. (Formation of Graft Polymerized Layer) The same operation as in Example 26 was performed except that propyl acid chloride was used instead of stearic acid chloride. About the obtained particles,
The mechanical strength and the orientation state were evaluated in the same manner as in Example 25. The results are shown in Table 4.

[0192]

[Table 4]

Example 32 (Preparation of fine particles having a reducing group on the surface) A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was homogenized. The particle size was adjusted by stirring.
Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream while stirring,
The reaction was performed for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5. When surface analysis was performed by TOF-SIMS,
OH groups derived from polyvinyl alcohol were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
95 parts by weight of ion-exchanged water, 10 parts by weight of hydroxyethyl methacrylate, and 5 parts by weight of the seed particles obtained by the above operation were added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. To this, 10 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 1N aqueous nitric acid solution was added and reacted for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Introduction of Polymerizable Vinyl Group) To a separable flask, 100 parts by weight of toluene and 5 parts by weight of the particles obtained by the above operation were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Further, di-n-butyltin dilaurate diluted with 10 parts by weight of toluene 0.0
5 parts by weight was added and sufficiently stirred. 5 parts by weight of methacryloxyethyl isocyanate diluted with 10 parts by weight of toluene was added dropwise thereto, and after completion of the addition, the temperature of the system was raised to 80 ° C., and the reaction was continued for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Formation of Graft Polymerization Layer Having Epoxy Group) In a separable flask, 50 parts by weight of toluene, 50 parts by weight of glycidyl methacrylate and 5 parts by weight of the particles obtained by the above operation were added, and sufficiently dispersed by a sonicator. Thereafter, stirring was performed uniformly. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 1 hour. Then change the system to 6
The temperature was raised to 0 ° C., and 0.1 part by weight of benzoyl peroxide dissolved in 10 parts by weight of toluene was added dropwise. After continuing the reaction for 4 hours, 0.1 part by weight of benzoyl peroxide dissolved in 10 parts by weight of toluene was further added dropwise, and the reaction was continued for 4 hours. After completion of the reaction, the reaction solution was taken out, and the released homopolymer was recovered with toluene. After that, the particles and toluene were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with toluene and acetone, and dried under reduced pressure with a vacuum drier. The mechanical strength of the obtained particles was determined in Example 1.
The liquid crystal dissolution test and the evaluation of adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Example 33 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Functional Group) The same operation as in Example 32 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Epoxy Group) The same operation as in Example 32 was performed except that glycidyl methacrylate was 30 parts by weight and methyl methacrylate 20 parts by weight instead of 50 parts by weight of glycidyl methacrylate.
About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Example 34 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Functional Group) The same operation as in Example 32 was performed. (Introduction of an active group having a polymerization initiating ability) 30 parts by weight of dimethylformamide, 5 parts by weight of triethylamine, and 5 parts by weight of the particles obtained by the above operation were added to a separable flask, and sufficiently dispersed by a sonicator. Was stirred. To this, 5 parts by weight of 4,4-azobis-4-cyanovaleric acid chloride dissolved in 10 parts by weight of dimethylformamide was added dropwise. After the reaction was continued for 4 hours, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with dimethylformamide, methanol and acetone, and dried under reduced pressure with a vacuum drier. (Formation of Graft Polymerized Layer Having Epoxy Group) To a separable flask were added 50 parts by weight of toluene, 30 parts by weight of glycidyl methacrylate, 20 parts by weight of methyl methacrylate, and 5 parts by weight of the particles obtained by the above operation.
After sufficiently dispersing with a sonicator, the mixture was uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 1 hour. Next, the temperature of the system was raised to 70 ° C., and the reaction was continued for 7 hours.

After the completion of the reaction, the reaction solution was taken out, the homopolymer liberated was recovered with toluene, and then the particles and toluene were separated by filtration with a 3 μm membrane filter.
The particles were sufficiently washed with toluene and acetone, and dried under reduced pressure with a vacuum drier. About the obtained particles,
The mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Example 35 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 32 was performed.

(Formation of Graft Polymerized Layer Having Functional Group)
100 parts by weight of ion-exchanged water, 30 parts by weight of isopropyl alcohol, 45 parts by weight of glycidyl methacrylate and 5 parts by weight of the seed particles obtained by the above operation are added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly stirred. Was done. In addition, ammonium persulfate 0.1.
15 parts by weight and 0.003 parts by weight of sodium bicarbonate were added, sufficiently dissolved, and stirred. The system was once depressurized with a pump, and then nitrogen gas was introduced and stirring was continued for 30 minutes.
The temperature was raised to 50 ° C., and the reaction was continued for 2 hours. Two hours later, the system was cooled, and the reaction was stopped by adding 100 parts by weight of tetrahydrofuran and a small amount of hydroquinone. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran, and dried under reduced pressure with a vacuum drier.

(Introduction of Polymerizable Vinyl Group) To a separable flask, 80 parts by weight of toluene and 5 parts by weight of the particles obtained by the above operation were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Further, 5 parts by weight of methacrylic acid diluted with 10 parts by weight of toluene was added and sufficiently stirred. Next, the temperature of the system was raised to 60 ° C., and the reaction was continued for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Formation of Graft Polymerized Layer Having Epoxy Group) The same operation as in Example 32 was performed. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Example 36 (Production of fine particles having a reducing group on the surface) 50 parts by weight of trimethylolpropane triacrylate, 40 parts by weight of divinylbenzene, and 10 parts by weight of acrylonitrile were uniformly mixed, and 12 parts by weight of carbon black was added thereto. Was added and stirred for 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide were uniformly mixed with the monomer mixture, and further mixed with a 3% aqueous solution of polyvinyl alcohol 85%.
0 parts by weight. After sufficient stirring and particle size adjustment, the mixture was heated to 80 ° C. under a nitrogen stream and reacted for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm, a CV value of 5.0, and were black. When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface.
The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 32 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Epoxy Group) Example 3
The same operation as in Example 2 was performed. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Example 37 (Preparation of fine particles having a reducing group on the surface) In 800 parts by weight of a 3% aqueous solution of surfactant Hytenol N-08 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 80 parts by weight of divinylbenzene, A mixture of 20 parts by weight of ethyl methacrylate and 2 parts by weight of benzoyl peroxide was added, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The resulting fine particles had an average particle size of 6.0 μm and a CV
Value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 32 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Epoxy Group) Example 3
The same operation as in Example 2 was performed. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Comparative Example 13 A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was stirred with a homogenizer to adjust the particle size. 80 ° C under a nitrogen stream with stirring
And the reaction was carried out for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm,
V value = 5. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Comparative Example 14 To 80 g of the fine particles obtained in Comparative Example 13, 5 g of methyl methacrylate-glycidyl methacrylate copolymer particles of 0.2 μm were mixed and adsorbed in an alcohol solvent. This was coated by heat treatment to synthesize particles having a reaction layer. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Comparative Example 15 Surfactant Hitenol N-08 (Daiichi Kogyo Seiyaku Co., Ltd.)
A mixture of 20 parts by weight of divinylbenzene, 80 parts by weight of hydroxyethyl methacrylate, and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of the above, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After washing the obtained fine particles with hot water and methanol,
A classification operation was performed. The obtained fine particles have an average particle size of 6.
0 μm, CV value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

Comparative Example 16 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Functional Group) The same operation as in Example 32 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 32 was performed. (Formation of Graft Polymerized Layer Having Epoxy Group) Instead of glycidyl methacrylate, methyl methacrylate 5
The same operation as in Example 32 was performed except that the amount was 0 part by weight. About the obtained particles, the mechanical strength was evaluated in the same manner as in Example 1, and the liquid crystal dissolution test and the evaluation of the adhesion were performed in the same manner as in Example 8. Table 5 shows the results.

[0212]

[Table 5]

Example 38 (Preparation of fine particles having a reducing group on the surface) A mixture of 100 parts by weight of divinylbenzene and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, and the mixture was homogenized. The particle size was adjusted by stirring.
Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream while stirring,
The reaction was performed for 15 hours. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm and a CV value of 5. When surface analysis was performed by TOF-SIMS,
OH groups derived from polyvinyl alcohol were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
95 parts by weight of ion-exchanged water, 10 parts by weight of hydroxyethyl methacrylate, and 5 parts by weight of the seed particles obtained by the above operation were added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. To this, 10 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 1N aqueous nitric acid solution was added and reacted for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Introduction of Polymerizable Vinyl Group) To a separable flask, 100 parts by weight of toluene and 5 parts by weight of the particles obtained by the above operation were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Further, di-n-butyltin dilaurate diluted with 10 parts by weight of toluene 0.0
5 parts by weight was added and sufficiently stirred. 5 parts by weight of methacryloxyethyl isocyanate diluted with 10 parts by weight of toluene was added dropwise thereto, and after completion of the addition, the temperature of the system was raised to 80 ° C., and the reaction was continued for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Formation of Graft Polymerization Layer Having Long-Chain Alkyl Group) In a separable flask, 50 parts by weight of toluene,
After 50 parts by weight of stearyl methacrylate and 5 parts by weight of the particles obtained by the above operation were added and sufficiently dispersed by a sonicator, the mixture was uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 1 hour. Next, the temperature of the system was raised to 60 ° C., and 0.1 part by weight of benzoyl peroxide dissolved in 10 parts by weight of toluene was added dropwise. After continuing the reaction for 4 hours, 0.1 part by weight of benzoyl peroxide dissolved in 10 parts by weight of toluene was further added dropwise, and the reaction was continued for 4 hours.

After the completion of the reaction, the reaction solution was taken out, and the released homopolymer was recovered with toluene. After that, the particles and toluene were separated by filtration with a 3 μm membrane filter.
The particles were sufficiently washed with toluene and acetone, and dried under reduced pressure with a vacuum drier. About the obtained particles,
The mechanical strength was evaluated in the same manner as in Example 1, and the orientation state was evaluated in the same manner as in Example 20. Table 6 shows the results
It was shown to.

Example 39 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 38 was performed. (Formation of Graft Polymer Layer Having Functional Group) The same operation as in Example 38 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 38 was performed.

(Formation of Graft-Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 38 was carried out except that 30 parts by weight of octyl methacrylate and 20 parts by weight of methyl methacrylate were used instead of stearyl methacrylate. Was. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 38. The results are shown in Table 6.

Example 40 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 38 was performed. (Formation of Graft Polymer Layer Having Functional Group) The same operation as in Example 38 was performed.

(Introduction of Active Group Having Polymerization Initiating Ability) A separable flask was charged with 30 parts by weight of dimethylformamide,
After 5 parts by weight of triethylamine and 5 parts by weight of the particles obtained by the above operation were added and sufficiently dispersed by a sonicator, the mixture was uniformly stirred. To this, 5 parts by weight of 4,4-azobis-4-cyanovaleric acid chloride dissolved in 10 parts by weight of dimethylformamide was added dropwise. After the reaction was continued for 4 hours, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with dimethylformamide, methanol and acetone, and dried under reduced pressure with a vacuum drier.

(Formation of Graft Polymerization Layer Having Long-Chain Alkyl Group) A separable flask was charged with 50 parts by weight of toluene,
After 50 parts by weight of stearyl methacrylate and 5 parts by weight of the particles obtained by the above operation were added and sufficiently dispersed by a sonicator, the mixture was uniformly stirred. Nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 1 hour. Next, the temperature of the system was raised to 70 ° C., and the reaction was continued for 7 hours.

After completion of the reaction, the reaction solution was taken out, and the released homopolymer was recovered with toluene. After that, the particles and toluene were separated by filtration with a 3 μm membrane filter.
The particles were sufficiently washed with toluene and acetone, and dried under reduced pressure with a vacuum drier. About the obtained particles,
Evaluation of mechanical strength and orientation was performed in the same manner as in Example 38. The results are shown in Table 6.

Example 41 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 38 was performed.

(Formation of Graft Polymerized Layer Having Functional Group)
100 parts by weight of ion-exchanged water, 30 parts by weight of isopropyl alcohol, 45 parts by weight of glycidyl methacrylate and 5 parts by weight of the seed particles obtained by the above operation are added to a separable flask, sufficiently dispersed by a sonicator, and then uniformly stirred. Was done. In addition, ammonium persulfate 0.1.
15 parts by weight and 0.003 parts by weight of sodium bicarbonate were added, sufficiently dissolved, and stirred. The system was once depressurized with a pump, and then nitrogen gas was introduced and stirring was continued for 30 minutes.
The temperature was raised to 50 ° C., and the reaction was continued for 2 hours. Two hours later, the system was cooled, and the reaction was stopped by adding 100 parts by weight of tetrahydrofuran and a small amount of hydroquinone. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with tetrahydrofuran, and dried under reduced pressure with a vacuum drier.

(Introduction of Polymerizable Vinyl Group) To a separable flask, 80 parts by weight of toluene and 5 parts by weight of the particles obtained by the above operation were added, sufficiently dispersed by a sonicator, and then uniformly stirred. Further, 5 parts by weight of methacrylic acid diluted with 10 parts by weight of toluene was added and sufficiently stirred. Next, the temperature of the system was raised to 60 ° C., and the reaction was continued for 5 hours. After the completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The particles were sufficiently washed with ethanol and acetone, and dried under reduced pressure using a vacuum drier.

(Formation of Graft Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 38 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 38. The results are shown in Table 6.

Example 42 (Preparation of fine particles having a reducing group on the surface) 50 parts by weight of trimethylolpropane triacrylate, 40 parts by weight of divinylbenzene, and 10 parts by weight of acrylonitrile were uniformly mixed, and 12 parts by weight of carbon black was added thereto. Was added and stirred for 48 hours using a bead mill. 2 parts by weight of benzoyl peroxide were uniformly mixed with the monomer mixture, and further mixed with a 3% aqueous solution of polyvinyl alcohol 85%.
0 parts by weight. After sufficient stirring and particle size adjustment, the mixture was heated to 80 ° C. under a nitrogen stream and reacted for 15 hours. After the obtained fine particles were washed with hot water and methanol, a classification operation was performed. The obtained fine particles had an average particle size of 6.0 μm, a CV value of 5.0, and were black. When surface analysis was performed by TOF-SIMS, OH groups derived from polyvinyl alcohol were confirmed on the surface.
The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 38 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 38 was performed. (Formation of Graft Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 38 was performed. About the obtained particles,
Evaluation of mechanical strength and orientation was performed in the same manner as in Example 38. The results are shown in Table 6.

Example 43 Surfactant Hytenol N-08 (Daiichi Kogyo Seiyaku Co., Ltd.)
A mixture of 80 parts by weight of divinylbenzene, 20 parts by weight of hydroxyethyl methacrylate, and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of a 3% aqueous solution of the above, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours. After washing the obtained fine particles with hot water and methanol,
A classification operation was performed. The obtained fine particles have an average particle size of 6.
0 μm, CV value = 5.0. When surface analysis was performed by TOF-SIMS, OH groups derived from hydroxyethyl methacrylate were confirmed on the surface. The following operation was performed using these fine particles as seed particles.

(Formation of Graft Polymerized Layer Having Functional Group)
The same operation as in Example 38 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 38 was performed. (Formation of Graft Polymerized Layer Having Long-Chain Alkyl Group) The same operation as in Example 38 was performed. About the obtained particles,
Evaluation of mechanical strength and orientation was performed in the same manner as in Example 38. The results are shown in Table 6.

Comparative Example 17 (Preparation of fine particles having a reducing group on the surface) The same operation as in Example 38 was performed. (Formation of Graft Polymer Layer Having Functional Group) The same operation as in Example 38 was performed. (Introduction of Polymerizable Vinyl Group) The same operation as in Example 38 was performed.

(Formation of Graft-Polymerized Layer Having Long-Chain Alkyl Group) Example 3 was repeated except that 50 parts by weight of methyl methacrylate was used instead of stearyl methacrylate.
The same operation as in No. 8 was performed. The obtained particles were evaluated for mechanical strength and orientation state in the same manner as in Example 38. The results are shown in Table 6.

[0234]

[Table 6]

[0235]

Since the spacer for a liquid crystal display element of the present invention has the above-described structure, it has a function such as an abnormal alignment preventing property while maintaining the mechanical strength required for the spacer. Therefore, by using the spacer for a liquid crystal display element of the present invention, it is possible to easily improve the abnormal alignment phenomenon of the liquid crystal, the adhesion of the spacer, the dispersibility, etc. Can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a liquid crystal display device of the present invention.

[Description of Signs] 1 seal 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 polarizing sheet 13 polarizing sheet

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-101713 (JP, A) JP-A-8-43834 (JP, A) JP-A-7-300586 (JP, A) JP-A-7-300 300587 (JP, A) JP-A-1-144429 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02F 1/1339

Claims (9)

(57) [Claims] An oxidizing agent is reacted with fine particles having a reducing group on the surface thereof to generate radicals on the surface of the fine particles.
A spacer for a liquid crystal display element, wherein a polymer layer is formed on the surface of the fine particles starting from the radical. 2. The spacer according to claim 1, wherein the oxidizing agent is a cerium salt. An oxidizing agent is reacted with the fine particles having a reducing group on their surface to generate radicals on the surface of the fine particles.
A spacer for a liquid crystal display element, wherein a reactive graft polymer layer is formed on the surface of the fine particles by reacting a polymerizable monomer having an epoxy group with the radical as a starting point. 4. A method in which an oxidizing agent is allowed to react with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles.
By reacting a polymerizable monomer having an epoxy group and a polymerizable monomer having an ethylene glycol group with the radical as a starting point, a reactive graft polymer layer is formed on the surface of the fine particles. For a liquid crystal display element. 5. A method in which an oxidizing agent is reacted with fine particles having a reducing group on the surface to generate radicals on the surface of the fine particles.
Starting from the radical, a polymerizable monomer having a long-chain alkyl group is reacted to form a graft polymer layer having a long-chain alkyl group on the surface of the fine particles. Spacer. 6. A fine particle having a reducing group on the surface thereof is reacted with an oxidizing agent to generate a radical on the surface of the fine particle.
By reacting a polymerizable monomer having a functional group with the radical as a starting point, a graft polymer layer having a functional group is formed on the surface of the fine particles, and further a long chain is formed on the graft polymer layer having the functional group. A spacer for a liquid crystal display element, characterized by reacting an alkyl compound. 7. A fine particle having a reducing group on the surface thereof is reacted with an oxidizing agent to generate a radical on the surface of the fine particle.
By reacting a polymerizable monomer having a functional group with the radical as a starting point, a graft-polymerized layer having a functional group is formed on the surface of the fine particles. After introducing a vinyl group and / or an active group having a polymerization initiating ability, by reacting a polymerizable monomer having an epoxy group, a graft polymerization layer having an epoxy group is formed on the surface of the graft polymerization layer having the functional group. A spacer for a liquid crystal display element, characterized by being formed. 8. A fine particle having a reducing group on the surface thereof is reacted with an oxidizing agent to generate a radical on the surface of the fine particle,
By reacting a polymerizable monomer having a functional group with the radical as a starting point, a graft-polymerized layer having a functional group is formed on the surface of the fine particles. After introducing a vinyl group and / or an active group having a polymerization initiating ability, a polymerizable monomer having a long-chain alkyl group is reacted to have a long-chain alkyl group on the surface of the graft polymer layer having the functional group. A spacer for a liquid crystal display element, comprising a graft polymerized layer. 9. A glass substrate on which an alignment film and a transparent electrode are arranged, facing each other via a spacer for a liquid crystal display element according to claim 1, 2, 3, 4, 5, 6, 7, or 8. A liquid crystal display element, wherein a liquid crystal is sealed between the glass substrates.