JP2002090753A - Spacer for liquid crystal display device, method for dispersing the same, liquid crystal display device, and method for manufacturing liquid crystal display device - Google Patents

Abstract

(57) [Summary] PROBLEM TO BE SOLVED: To disperse evenly and uniformly on a substrate by a dry dispersing method, and to disperse a single particle state on a substrate by a dry dispersing method even if a surface treatment that can make dispersing particularly difficult is applied. Provided are a spacer for a liquid crystal display device, a method for dispersing the same, a liquid crystal display device, and a method for manufacturing the liquid crystal display device. SOLUTION: This is a spacer for a liquid crystal display device in which a surface treatment layer made of a thermoplastic resin is formed on the surface of spacer base particles, and the spacer base particles and the surface are sprayed by a dry spray method. The treatment layer is a spacer for a liquid crystal display device that is charged to the same polarity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a liquid crystal display device.
The present invention relates to a spacer for a liquid crystal display device for forming and maintaining a thickness of a liquid crystal layer between two substrates, a method for dispersing the spacer, a liquid crystal display device, and a method for manufacturing a liquid crystal display device.

[0002]

2. Description of the Related Art As shown in FIG. 1, a liquid crystal display device has a structure in which liquid crystal is injected into a gap between two substrates and an electric field is applied to a selective portion to display information such as a specific figure or character. is there. It is a spacer for a liquid crystal display device (hereinafter, also referred to as a spacer) that keeps the gap between the two substrates constant.

Since the spacer is randomly present in the gap between the substrates, that is, in the liquid crystal, the orientation of the liquid crystal molecules is disturbed at the interface between the liquid crystal and the spacer, and light leaks around the spacer, causing a reduction in contrast. I have. As a preventive measure, a spacer having a surface treatment layer formed on the spacer surface so as not to disturb the alignment of the liquid crystal has been put to practical use.

Further, as disclosed in Japanese Patent Application Laid-Open No. 2000-155322, it is possible to prevent the movement of the spacer in the manufacturing process of the liquid crystal display panel and to prevent the display quality from deteriorating due to the movement of the spacer after the completion of the liquid crystal display device. To form a surface treatment layer made of a thermoplastic resin on the surface of the spacer base material particles, and use a heating process during the production of the liquid crystal display panel to melt the surface treatment layer and fix the spacer to the substrate. Have been used at the same time.

When manufacturing a liquid crystal display device, it is necessary to uniformly and uniformly spread the spacers on the substrate without agglomerating the spacers. Conventionally, for spraying the spacers on the substrate, a wet spraying method in which the spacers are dispersed in a liquid such as Freon and sprayed on the substrate and the liquid is vaporized at the same time has been used. However, the use of liquids such as chlorofluorocarbons has been restricted or prohibited due to environmental problems and the like.
A dry spraying method of spraying spacers using air, nitrogen gas, or the like, as disclosed in Japanese Patent No. 1-64858, has come to be used frequently.

In the dry spraying method, a spacer is put on a gas flow and spread on a substrate through a thin pipe.
At this time, the spacers are charged to a single polarity by repeating contact and collision with the inner wall of the pipe, and become a single particle state by the electrostatic repulsion of the spacers, and are dispersed on the substrate. FIG. 2 shows a schematic view of the dry sprayer. The spacer is measured in a predetermined amount by a measuring (supplying) feeder, and is sprayed on the substrate via a pipe by a gas such as nitrogen.

However, since the spacer on which the surface treatment layer is formed has a structure in which a new surface is formed on the surface of the spacer base material particles, the spacer exhibits a charging behavior different from that of the conventional spacer, and when the spacer is sprayed on the substrate. However, there is a problem in that a problem of agglomeration or beading or the like easily occurs. Further, even with the non-surface treated spacer, if the chargeability at the time of spraying is insufficient, defects such as aggregation and a decrease in the number of sprays occur. When the spacers cause aggregation, etc.
Defects such as non-uniform gaps and recognition of display defects occur, which degrade display quality and lower product yield.

[0008]

SUMMARY OF THE INVENTION In view of the above, the present invention has been made in consideration of the above circumstances, and the present invention has been made in view of the above circumstances. A spacer for a liquid crystal display device that can be sprayed in a single particle state on the spacer, a method of spraying the spacer, a liquid crystal display device,
It is another object of the present invention to provide a method for manufacturing a liquid crystal display device.

[0009]

A first aspect of the present invention is a spacer for a liquid crystal display device in which a surface treatment layer made of a thermoplastic resin is formed on the surface of a spacer base particle, wherein the spacer is sprayed by a dry spraying method. Accordingly, the spacer base particles and the surface treatment layer are spacers for a liquid crystal display device charged to the same polarity.

[0010] The present invention 2 is a spacer for a liquid crystal display device, wherein a surface treatment layer made of a thermoplastic resin is formed on the surface of the spacer base material particles. The particles and the surface treatment layer are charged to different polarities, and the thickness of the surface treatment layer is 250
ス ペ ー サ The above is a spacer for a liquid crystal display device.

[0011] The present invention 3 is a liquid crystal which is positively charged by being sprayed by a dry spraying method and has at least a surface thereof containing an amino group or a group containing a structure represented by the following general formula (1). It is a spacer for a display device.

[0012]

Embedded image

A fourth aspect of the present invention is a method of spraying the spacer for a liquid crystal display device according to the first, second, or third aspect of the present invention, wherein the spacer for a liquid crystal display device is sprayed by a dry spraying method. This is a method of spraying a spacer for a liquid crystal display device, which is positively charged and has a dew point of a gas used for dry spraying of -75 to -50 ° C.

A fifth aspect of the present invention is a method of spraying a spacer for a liquid crystal display device according to the first or second aspect of the present invention, wherein the spacer for a liquid crystal display device is sprayed by a dry spraying method. This is a method of spraying a spacer for a liquid crystal display device, which is negatively charged and has a dew point of a gas used for dry spraying of −60 to −20 ° C. Hereinafter, the present invention will be described in detail.

The spacer for a liquid crystal display device of the present invention 1 has a surface treatment layer made of a thermoplastic resin formed on the surface of the spacer base particle. The constituent material of the spacer base particles is not particularly limited, and may be any of an inorganic material and an organic material. The inorganic material is not particularly limited, and examples thereof include silicate glass, borosilicate glass, lead glass, soda-lime glass, alumina, and alumina silicate. The organic material is not particularly limited, and examples thereof include a synthetic resin.

As the spacer base particles, those made of a synthetic resin are preferably used. In the case of using the spacer base particles made of the above-mentioned inorganic material, in general, it is often difficult to control the charge because the composition cannot be arbitrarily changed. Further, since the thermal expansion coefficient of the liquid crystal is largely different from that of the liquid crystal, the liquid crystal cannot follow the temperature change and may cause a defect such as low-temperature foaming.
On the other hand, when using spacer base particles made of an organic material such as a synthetic resin, a monomer having various charging characteristics can be arbitrarily mixed, so that the composition can be easily changed for charge control, Since the coefficient of thermal expansion does not change much, problems such as low-temperature foaming do not occur.

Examples of the above synthetic resin include those obtained by polymerizing a monomer having an ethylenically unsaturated group. The monomer having an ethylenically unsaturated group includes a non-crosslinkable monomer and a crosslinkable monomer.

The non-crosslinkable monomer includes, for example,
Styrene monomers such as styrene and α-methylstyrene;
Carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, and maleic anhydride; methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) A) alkyl (meth) acrylates such as acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate; Hydroxyl group-containing (meth) acrylates such as glycerol (meth) acrylate and polyoxyethylene (meth) acrylate; oxygen atom-containing (meth) acrylates such as glycidyl (meth) acrylate;
Amino group-containing (meth) acrylates such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate; acid amides and imides such as (meth) acrylamide, maleimide and phenylmaleimide; and nitriles such as (meth) acrylonitrile Monomers; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether; acid vinyl esters such as vinyl acetate, vinyl butyrate, vinyl laurate, and vinyl stearate; unsaturated hydrocarbons such as ethylene, propylene, and isoprene; Examples include halogen-containing monomers such as fluoromethyl (meth) acrylate, pentafluoroethyl (meth) acrylate, vinyl chloride, vinyl fluoride, and chlorostyrene.

Examples of the crosslinkable monomer include tetramethylolmethanetetra (meth) acrylate, tetramethylolmethanetri (meth) acrylate, tetramethylolmethanedi (meth) acrylate, and trimethylolpropanetri (meth) acrylate. , Dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate, glycerol di (meth)
Polyfunctional (meth) acrylates such as acrylate, polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate; triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallyl acrylamide, diallyl ether Silane-containing monomers such as γ- (meth) acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, and vinyltrimethoxysilane.

These monomers having an ethylenically unsaturated group may be used alone or in combination of two or more. Considering the mechanical strength, the spacer base particles preferably contain at least 20% by weight of a crosslinkable monomer as a component of the synthetic resin.

As a method for producing the spacer base particles used in the present invention by polymerizing the above-mentioned monomer having an ethylenically unsaturated group, for example, a method of suspension polymerization in the presence of a radical polymerization initiator (particularly, Japanese Unexamined Patent Publication (Kokai) No. Hei 6-273774), a method of polymerizing non-crosslinked seed particles by swelling a monomer together with a radical polymerization initiator (JP-A-1-81810).
And other known methods.

The spacer base particles preferably have an average particle size in the range of 0.1 to 100 μm.
Those having a range of 0 μm are more preferable. The spacer base particles may be colorless and transparent, or may be colored with a pigment, a dye, or the like, if necessary, and provided with a light-shielding property.

As for the mechanical strength of the spacer base particles, the 10% K value is preferably 250 to 1000 because it functions as a gap retaining material for the spacer for a liquid crystal display device. In addition, the 10% K value means that the spacer base particles are formed by using a micro compression tester (PCT-200, manufactured by Shimadzu Corporation) with a diameter of 50 μm made of diamond in accordance with Japanese Patent Publication No. 6-503180. On the smooth end of the cylinder,
The compression hardness is 0.27 g / sec and the maximum test load is 10 g.

K = (3 / √2) · F · S^-3/2・ R^-1/2  F: Load value at 10% compression deformation of spacer base particles
(Kg) S: Compressive deformation at 10% compressive deformation of spacer base particles
Position (mm) R: Radius of spacer base material particles (mm)

If the 10% K value is less than 250, the strength of the spacer base particles is not sufficient, so that the spacer is broken when assembling the liquid crystal display device, and an appropriate gap is hardly formed. On the other hand, if the 10% K value exceeds 1000, abnormalities such as low-temperature foaming may occur when incorporated into a liquid crystal display device.

The thermoplastic resin is not particularly restricted but includes, for example, polyethylene resins, polypropylene resins, polyvinyl chloride resins, polystyrene resins, polycarbonate resins, acrylic resins and the like.

Examples of the method of forming a surface treatment layer of a thermoplastic resin on the surface of the spacer base particles include a method of coating the spacer base particles with a thermoplastic resin, and a method of coating a polymerizable monomer on the surface of the spacer base particles. And a known method such as a method of introducing a surface treatment layer made of a thermoplastic resin by graft polymerization. In the case of the former method, the latter method is preferable because the coating layer may peel off from the spacer base material particles and contaminate the liquid crystal.

The method for introducing the surface treatment layer by the graft polymerization is not particularly limited. One of the methods for introducing the surface treatment layer by the graft polymerization is, for example, as follows.
When a reducing group is present on the surface of the spacer base material particles, an oxidizing agent is reacted to generate radicals on the surface of the spacer base material particles, and the polymerizable monomer is graft-polymerized from the radicals to form a surface treatment layer. Forming method. Examples of the reducing group include a hydroxyl group, a thiol group, an amino group, an aldehyde group, and a mercapto group.

Examples of the oxidizing agent include cerium salts, persulfates, hydrogen peroxide, dimethylaniline, periodate, permanganate, alkylboron and the like. Of these, cerium salts are preferred. 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 nitrate, cerium ammonium pyrophosphate, and cerium iodide.

The above-mentioned spacer base particles having a reducing group are dispersed in a solvent, and a polymerizable monomer and a cerium salt are added thereto to carry out a polymerization reaction. At this time, in order to increase the reaction rate of the polymerization system, the pH may be adjusted to 6 or less by adding an acid or a salt such as nitric acid.

As another method for introducing a surface treatment layer by the above graft polymerization, a compound having a functional group capable of reacting with a functional group on the surface of the spacer base material particles and having a polymerizable double bond is used. After reacting with the functional groups on the surface of the spacer base particles to obtain spacer base particles having a double bond introduced on the surface, a polymerization initiator is acted on the spacer base particles in the presence of a polymerizable monomer. And performing a graft polymerization reaction.

The combination of the functional group on the surface of the spacer base particles with the functional group of the compound having a double bond is not particularly limited. For example, a functional group containing an active hydrogen such as a hydroxyl group or an amino group and an isocyanate group may be used. And combinations with functional groups such as carboxylic acid halides, alkoxyl groups, and epoxy groups.

Examples of the polymerizable monomer used in the surface treatment layer composed of the thermoplastic resin include the above-mentioned non-crosslinkable monomers. These polymerizable monomers may be used alone or in combination of two or more. In addition, it is possible to prevent abnormal orientation around the spacer and to improve the adhesion to the substrate by the thickness and the composition of the surface treatment layer.

The glass transition point of the thermoplastic resin is preferably at least room temperature. If the glass transition point of the thermoplastic resin is lower than room temperature, self-aggregation of the spacers occurs, making dry spraying difficult. More preferably, it is 50 ° C. or higher.

The spacer for a liquid crystal display device according to the first aspect of the present invention is characterized in that the spacer base particles and the surface treatment layer are charged to the same polarity by being sprayed by a dry spraying method. The dry spraying method is a method in which a spacer is put on a gas flow of air, nitrogen, or the like, and is sprayed on a substrate through a thin pipe. At this time, the spacer contacts the inner wall of the pipe,
By repeating collisions, the spacers are charged to a single polarity, and become a single particle state by the electrostatic repulsion between the spacers, and are dispersed on the substrate.

The charging of the spacer depends on the so-called charging sequence of the spacer material and the piping material used for spraying. For example, if the piping material has a strong negative charge tendency, the spacer will have a positive charge tendency. Conversely, if the piping material has a strong positive charge, the spacer will have a negative charge. The charge of the spacer is
It is also affected by other constituent materials other than the spacer base particles and the surface treatment layer, the gas used, the dew point, the pipe used, the spray environment, and the like.

Basically, the charging behavior is a phenomenon in the vicinity of the spacer surface. Generally used spacer base particles have a particle size of about 1 to 10 μm, and a surface treatment layer is formed on the surface. Therefore, the thickness of the surface treatment layer is as thin as several hundreds to several thousand degrees. In this case, it was found that the charging behavior of the spacer tends to be influenced by both the spacer base particles and the surface treatment layer. For example, even if the same surface treatment layer is formed, if the spacer base material particles are different, the obtained spacers will be dispersed in different states. This is because the surface treatment layer of the spacer is thin, so that the charging characteristics of both the spacer base particles and the surface treatment layer appear.

As a result of the investigation, it has been found that when the surface treatment layer and the spacer base particles are charged to the same pipe with opposite polarities, aggregation or the like is likely to occur. That is, for example, when the surface treatment layer is positively charged with respect to the same pipe material, if a material that also positively charges the spacer base particles is selected, a uniform dispersion state without aggregation or the like can be obtained.

The chargeability of the spacer base particles and the surface treatment layer generally depends on the type and content of the polymerizable monomers constituting each, and depends on the piping material used for spraying and the polymerizability. Positive and negative charging properties are determined by the charging sequence with the monomer, and the strength can be controlled by the content of the polymerizable monomer. The chargeability between the spacer base particles and the surface treatment layer is greatly affected by the dew point of the gas used when the pipe used for spraying is SUS316 (electrolytic polishing product), but usually has the following tendency. . (1) When the polymerizable monomer constituting the spacer base material particle / surface treatment layer contains the following, it is likely to be positively charged; alkyl group, amino group, amide group, imide group, etc. (2) Spacer When the following are contained in the polymerizable monomers constituting the base particles and the surface treatment layer, they are easily negatively charged; halogen groups such as chlorine and fluorine, nitrile groups, carboxyl groups, hydroxyl groups, etc.

In order to confirm the charging polarity of the surface treatment layer alone with respect to the spraying pipe, a thermoplastic resin having the same composition as that of the surface treatment layer is prepared, crushed, powdered, and dispersed in the same manner as the spacer. Can be confirmed by

The spacer for a liquid crystal display device according to the second aspect of the invention has a surface treatment layer made of a thermoplastic resin formed on the surface of the spacer base particle. Examples of the spacer base particles and the thermoplastic resin include those similar to the first embodiment.

The spacer for a liquid crystal display device according to the second aspect of the invention is sprayed by a dry spray method, whereby the spacer base particles and the treatment layer are charged to different polarities, and the thickness of the surface treatment layer is 250 ° or more. It is characterized by the following. The composition of the spacer base particles is determined from the viewpoint of hardness and recovery rate, and the composition of the surface treatment layer is determined based on the type of liquid crystal used and the like. Therefore, if a suitable composition is selected from this viewpoint,
In some cases, the charging polarities of both spraying pipes are not always the same. Even if the spacer base particles and the surface treatment layer are charged to different polarities with respect to the same pipe,
It has been found that if the thickness of the surface treatment layer is not less than a certain value, it is possible to uniformly spread the surface treatment layer depending on the charging polarity. That is, in the present invention 2, even if the charge polarity of the spacer base particles and the surface treatment layer are different, it is possible to realize a uniform spraying state by setting the thickness of the surface treatment layer to 250 ° or more. It was completed based on the knowledge that

The spacer for a liquid crystal display device according to the third aspect of the present invention is positively charged by being sprayed by a dry spraying method.
Further, at least on the surface thereof, an amino group or a group containing a structure represented by the general formula (1) (hereinafter, also referred to as an amino group or the like) is provided. In the following, the spacer before the introduction of the amino group or the like is referred to as an untreated spacer.

When a surface-treated spacer or the like is used, the spacer is generally positively charged and sprayed in many cases. At this time, if the positive charge amount of the spacer is large, the spacer becomes a single particle state due to the electrostatic repulsion, and the bonding and aggregation of the spacer are suppressed. In addition, when the spacers fall onto the substrate, random dispersion can be achieved by uniformly dispersing the spacers without approaching other spacers by the electrostatic repulsive force near the spacers. However, if the charge amount of the spacer is small, the charge amount varies from spacer to spacer, or if the positive chargeability of the spacer is unstable, such as a mixture of positive and negative charged particles, sufficient electrostatic repulsion occurs. In this case, defects such as bonding and agglomeration of the spacers occur, and the distribution density of the spacers on the substrate varies, resulting in a non-uniform distribution state. The present inventors have proposed a spacer for a liquid crystal display device characterized in that the spacer is positively charged with respect to a pipe used in dry spraying, and at least an amino group or a compound represented by the above general formula (1) is provided on the surface of the spacer. It has been found that the positive chargeability is stabilized by having a group containing such a structure, and the present invention has been completed.

The amino group is not particularly restricted but includes, for example, -NH ₂ , -NH-CH ₃ , -NH-C ₂ H ₅ ,
_{-NH-C 3 H 7, -NH} -Ph, -NH-C 12 H 25,
_{-NH-C 18 H 37, -N} (CH 3) 2, -N (C 2 H
₅ ) ₂ , -N (C ₃ H ₇ ) ₂ , -N (CH ₃ ) (C ₂ H
_{5), - N (CH 3} ) 3 Cl, -N (C 2 H 5) 3 C
_{l, -N (C 3 H 7} ) 3 Cl, -N (CH 3) 3 HCO
_{3, -N (C 2 H 5} ) 3 HCO 3, -N (C 3 H 7) 3
HCO _{3 and the} like. Examples of the amino group include those containing a heterocyclic ring such as pyridine and imidazole, and salts thereof.

Examples of the group containing the structure represented by the general formula (1) include a carbamoyl group represented by the following general formula (2) and a derivative thereof, and an imide represented by the following general formula (3) And carbamates represented by the following general formula (4) and derivatives thereof, and the like.

[0047]

Embedded image

In the formula, R ¹ and R ² represent hydrogen or a group having 1 to 1 carbon atoms.
Represents 18 alkyl groups.

[0049]

(Equation 4)

In the formula, R ³ represents hydrogen or an alkyl group having 1 to 18 carbon atoms.

[0051]

(Equation 5)

In the formula, R ⁴ and R ⁵ are hydrogen or a group having 1 to 1 carbon atoms.
Represents 18 alkyl groups. R ^{1 to} R ⁵ may be a saturated alkyl group or an unsaturated alkyl group, and may have another substituent such as a hydroxyl group. When R ^{1 to} R ⁵ contain a long-chain alkyl group, they are also effective in preventing abnormal orientation around the spacer. The group containing the structure represented by the general formula (1) also includes a ureyl group, nylon, peptide and the like.

The method for introducing an amino group or the like into the surface of the untreated spacer is not particularly limited. For example, a polymerizable monomer containing an amino group or the like and a polymerizable monomer similar to that used in the present invention 1 are used. A method of copolymerizing with a monomer is exemplified. Examples of the polymerizable monomer containing an amino group or the like include amino group-containing (meth) such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and hydroxypropyltrimethylammonium (meth) acrylate. Examples include acrylates, amides and imides such as (meth) acrylamide, maleimide, methylmaleimide, phenylmaleimide, and N-vinylacetamide.

Further, for example, glycidyl (meth) acrylate is reacted with various primary and secondary amines under an appropriate catalyst, or a polymerizable monomer having an active hydrogen such as 2-hydroxyethyl (meth) acrylate is used. By reacting the polymer with various isocyanates or the like, a polymerizable monomer containing an arbitrary amino group or the like can be synthesized.
Examples of the isocyanates include methyl isocyanate, butyl isocyanate, phenyl isocyanate, allyl isocyanate, methacryloyloxyethyl isocyanate, and the like. These polymerizable monomers containing an amino group or the like may be used alone,
More than one species may be used in combination.

When the untreated spacer has a reactive group such as an ethylene oxide group, a hydroxyl group, a carboxyl group, or a silanol group or a substituent having an active hydrogen on the surface thereof,
The amino group and the like can be introduced into the surface of the untreated spacer by reacting the untreated spacer with the primary and secondary amines and the isocyanates.

The spacer for a liquid crystal display device according to the third aspect of the present invention may have no surface treatment layer formed on the surface thereof. However, a surface treatment layer made of a thermoplastic resin is formed on the surface of the spacer base particles. Preferably, it is Examples of the spacer base particles and the thermoplastic resin used in the third aspect of the invention include those similar to those used in the first aspect of the invention.

In the case where the spacer for a liquid crystal display device of the present invention 3 has a structure in which a surface treatment layer made of a thermoplastic resin is formed on the surface of the spacer base particles, a method for introducing the amino group or the like into the surface treatment layer is as follows. Is not particularly limited, for example, a method of polymerizing a polymerizable monomer containing an amino group or the like in the same manner as the above-described method for introducing into an untreated spacer and coating the same on a surface treatment layer, containing an amino group or the like A method of mixing a polymerizable monomer to be formed with a polymerizable monomer constituting a thermoplastic resin and graft-polymerizing the mixture onto spacer base material particles.

In addition, similarly to the above-described method for introducing into the untreated spacer, after forming a surface treatment layer having a reactive group such as an ethylene oxide group, a hydroxyl group or a carboxyl group or active hydrogen on the surface of the spacer base material particle, An amino group or the like can be introduced by reacting with a primary or secondary amine or the above-mentioned isocyanates.

Specifically, for example, a method of coating the spacer base particles with a thermoplastic resin containing active hydrogen such as polyvinyl alcohol or a polymerizable monomer mixture containing 2-hydroxyethyl (meth) acrylate Is graft-polymerized on the surface of the spacer base material particles, and then modified using the above-mentioned isocyanates or the like.

When the spacers are sprayed using a spray pipe made of SUS316 (electropolished product), for example, halogen groups such as chlorine and fluorine, nitrile groups, carboxyl groups, hydroxyl groups, etc. are present in the untreated spacers or the surface treatment layer. Then, the negative side is charged. In this case, more amino groups and the like are required to obtain a stable positive charge. Therefore, when only dry spraying is important, it is better to add a large amount of amino groups and the like, but on the other hand, when the content of amino groups and the like is large, abnormal orientation around the spacer becomes remarkable. Occurs.

In order to exhibit stable positive charging characteristics and not to cause abnormal orientation around the spacer, the content of the amino group or the like in the untreated spacer or the surface treatment layer is determined by adjusting the content of the polymerizable monomer composition. When converted as a mixing ratio of a polymerizable monomer containing an amino group or the like, 0.01 to 5
It is preferably 0 mol%. When the amount is less than 0.01 mol%, the chargeability may vary, and when the amount exceeds 50 mol%, the orientation characteristics around the spacer may be impaired. More preferably, it is 0.1 to 25 mol%. Further, as the polymerizable monomer containing the amino group or the like, 4
When a secondary ammonium chloride is used, the specific resistance of the liquid crystal may be hindered.

The spacer for a liquid crystal display device according to the third aspect of the present invention preferably has a charge amount of 60 μC / g or more when the dew point of the gas used for dry spraying is −75 to −50 ° C. When the dew point of the gas used for dry spraying is −75 to −50 ° C. and the charge amount of the spacer is 60 μC / g or more,
It has a sufficient electrostatic repulsion, exhibits stable positive charging characteristics, and is unlikely to cause problems during dry spraying such as aggregation of spacers and a decrease in the number of sprays. When the charge amount of the spacer is less than 60 μC / g, the electrostatic repulsive force is not sufficient, and the aggregation of the spacer is liable to occur. The electric repulsive force becomes insufficient, and uneven distribution and the like are likely to occur.

In this specification, the charge amount of the spacer means the charge amount at the time of spraying. As a method for measuring the charge amount of the powder, a blow-off method, an ESPART analyzer (manufactured by Hosokawa Micron Corporation) and the like are generally known. However, these methods mix the powder with iron powder or the like and stir the powder. Is to measure the charge amount of the sample. However, the charging at the time of spraying is caused by repeated contact and collision of the spacer with the inner wall of the pipe, and thus basically differs from charging behavior due to contact with iron powder or the like. Since the charge varies depending on the contacting party, the charge amount of the spacer at the time of spraying cannot be grasped from the charge amount with iron powder or the like. Also, as described above, since the charge amount of the spacer changes depending on the gas and moisture content used, it is not possible to grasp the relationship between the charge amount at the time of spraying the spacer and the chargeability due to contact with iron powder or the like. Have difficulty.

The charge amount of the spacer in the present invention is measured by a suction type Faraday gauge or the like, or a method based thereon. The suction-type Faraday gauge is a device in which two insulated metal containers are formed inside and outside. A filter is installed in the inside container, the charged particles are collected in the filter part by a suction pump, and the potential difference between the inner and outer containers is measured. Measure the amount of charge of the collected charged particles by measuring,
Next, the amount of charge is calculated by measuring the weight of the collected charged particles. The method of measuring the charge amount of the spacer in the present invention is, specifically, by installing a suction type Faraday gauge under the nozzle from which the spacer is discharged, and by suction-collecting the spacer sprayed from the nozzle. is there.

According to the spacer for a liquid crystal display device of the present invention, the charging characteristics are stable, and a dispersed state without aggregation or beads can be obtained. Further, by using a gas having a dew point suitable for the charging polarity, a more stable spraying state can be obtained.
A liquid crystal display device having high quality display performance using the spacer for a liquid crystal display device of the present invention is also one of the present invention.

The method for spraying a spacer for a liquid crystal display device according to the present invention 4 is a method for spraying the spacer for a liquid crystal display device according to the present invention 1, 2 or 3 by a dry spraying method. And the gas used for dry spraying has a dew point of −75 to −50 ° C.

The charging behavior of the spacer in dry spraying is as follows.
Basically, it depends on the charging sequence of the spacer material and the spray piping material, but is also affected by the moisture content of the gas used. When the spacer is positively charged with respect to the pipe, if the dew point of the gas used is −75 to −50 ° C., the gas can be sprayed on the substrate in a single particle state.

The amount of water in the gas can be determined by measuring the dew point. It is known that moisture in a gas exhibits negative ion behavior while passing through a pipe. Therefore, when the spacer is positively charged and the gas has a large amount of moisture, that is, when the dew point of the gas is higher than -50 ° C, the charge of the positively charged spacer tends to be neutralized. , The electrostatic repulsion between the spacers is reduced, which causes agglomeration, beads, and the like. On the other hand, when the spacer is positively charged, it is not a big problem that the gas is dry, that is, the dew point of the gas is lower than -75 ° C. May be seen. This is presumably because the charge amount rises excessively and reaches charge saturation, which causes a discharge-like phenomenon and conversely causes a decrease in the charge amount. In the present invention, the adjustment of the dew point can be performed by passing the dry gas through the inside of the tubular moisture permeable membrane.

The method for spraying the spacer for a liquid crystal display device according to the present invention 5 is a method for spraying the spacer for a liquid crystal display device according to the invention 1 or 2 by a dry spraying method. The gas used for dry spraying has a dew point of −60 to −20 ° C.

When the spacer is negatively charged, the gas used can be sprayed on the substrate in a single particle state if the dew point of the gas used is -60 to -20 ° C. Since the moisture in the gas shows the behavior of negative ions while passing through the pipe, when the spacer is negatively charged, the water showing the behavior of the negative ions tends to increase the charge amount of the spacer, so that the electrostatic charge is increased. The repulsive force increases, and a uniform dispersion state can be obtained. However, the gas has too much moisture, ie, the dew point of the gas is -2.
If the temperature is higher than 0 ° C., the spacers may be aggregated by water crosslinking and coalescing. On the other hand, if the gas is too dry, that is, if the dew point of the gas is lower than −60 ° C., negative charging tends to be difficult, and a rosary-like scattered state may appear.

In the inventions 1 to 5, pipes used for spraying by the dry spraying method include, for example, SUS and N
Metal pipes of i, Ti, Cu, Al and the like; resin pipes of Teflon (registered trademark) type, nylon type, polyethylene type, silicon type and the like. In the present inventions 1 to 5, examples of the gas used for spraying by the dry spraying method include nitrogen and air.

The present invention also relates to a method for manufacturing a liquid crystal display device, wherein the method for manufacturing a liquid crystal display device has a spacer dispersing step using the method for distributing spacers for a liquid crystal display device according to the fourth or fifth aspect of the present invention. It is.

[0073]

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 (Confirmation of Charging Polarity of Spacer Base Particle 1) Micropearl SP containing divinylbenzene as a main component as spacer base particle 1 (average particle size: 4.50 μm, 10% K value: 580, pool water) Chemical Industry Co., Ltd.) was prepared. As a dry sprayer, D
Using ISPA-μR (manufactured by Nisshin Engineering Co., Ltd.), SUS316 (electrolytic polishing product) was installed as a pipe so that it was electrically floated from the apparatus housing ground and grounded via an electrometer. The spacer base particles 1 were sprayed by a dry-type spraying apparatus equipped with the above-mentioned piping, and the flow of charge between the piping and the spacer base particles 1 was measured to confirm the charged polarity of the spacer base particles 1. Dew point -6
When a nitrogen gas at 0 ° C. was used and sprayed on the glass substrate, the spacer base particles 1 were positively charged, and a single-particle spray state without aggregation was obtained. In the following examples and comparative examples, the number of sprayed spacers, the presence or absence of aggregation,
The dispersion of the application was visually observed using a magnifying glass.
The amount of charge of the spacer and the like was measured using a suction type Faraday gauge.

(Surface Treatment of Spacer Base Particles 1) A mixture of 20 parts by weight of dimethylformamide, 4 parts by weight of isobornyl methacrylate, 4 parts by weight of isobutyl methacrylate, and 2 parts by weight of lauryl methacrylate was mixed with 1 part by weight of the spacer base particles 1. After the mixture was sufficiently dispersed by a sonicator, the mixture was uniformly stirred. Under a nitrogen atmosphere, 2 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 2N nitric acid aqueous solution was added thereto, and graft polymerization was performed at 40 ° C. for 4 hours. After the completion of the polymerization, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration with a 3 μm membrane filter. The obtained spacer was sufficiently washed with THF and methanol, and then dried under reduced pressure at room temperature with a vacuum drier. The obtained spacer was measured for particle diameter difference before and after graft polymerization using a Coulter counter, and the thickness of the graft polymerization layer was determined to be 200 °. Put the obtained surface-treated spacer into the sprayer,
Upon spraying, the spacer was positively charged, and a single-particle scattered state without aggregation was obtained.

(Confirmation of Charge Polarity of Surface Treatment Layer) In order to confirm the charge polarity of the resin having the same composition as the surface treatment layer, dimethylformamide 20 parts by weight, isobornyl methacrylate 4 parts by weight, isobutyl methacrylate 4 parts by weight, lauryl 2 parts by weight of methacrylate and 0.2 parts by weight of benzoyl peroxide were sufficiently mixed and polymerized at 90 ° C. for 8 hours while stirring under a nitrogen atmosphere. Thereafter, the solvent and the residual monomer were removed using an evaporator, and the obtained resin was crushed in a mortar, turned into a powder, and sprayed in the same manner as a spacer. As a result, the resin was positively charged.

(Comparative Example 1) (Preparation of spacer base particle 2) 40 parts by weight of acrylonitrile and 60 parts by weight of divinylbenzene were added to 800 parts by weight of a 3% by weight aqueous solution of polyvinyl alcohol (GH-20, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.). And a mixed solution of 2 parts by weight of benzoyl peroxide, 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 while stirring, and the reaction was carried out for 15 hours, followed by washing with hot ion-exchanged water. The obtained particles were classified to obtain spacer base particles 2 (average particle size: 4.88 μm, 10% K value: 710). The obtained spacer base particles 2 were put into a spraying machine and sprayed in the same manner as in Example 1. As a result, the spacer was negatively charged, and a single-particle sprayed state without aggregation was obtained.

The spacer base particles 2 were subjected to the same surface treatment as in Example 1, and the difference in particle diameter before and after graft polymerization was measured using a Coulter counter in the same manner as in Example 1 to reduce the thickness of the graft polymerization layer. When asked, it was 200Å.

The obtained spacer having been subjected to the surface treatment was put into a sprayer and sprayed in the same manner as in Example 1.
The spacer was charged positively and negatively, and agglomeration and scattered beads were generated.

Example 2 Using spacer base particles 2,
The same surface treatment as in Example 1 was performed except that the reaction time was extended to 6 hours. At this time, the particle size difference before and after the graft polymerization was measured using a Coulter counter as in Example 1, and the thickness of the graft polymerization layer was determined to be 300 °.

The spacer having been subjected to the surface treatment was put into a spraying machine and sprayed in the same manner as in Example 1. As a result, the spacer was positively charged, and a single-particle dispersed state without aggregation was obtained. .

(Reference Example 1) Using the surface-treated spacer obtained in Example 1, water was added to nitrogen gas, the dew point of nitrogen gas was set to -40 ° C, and spraying was performed in the same manner as in Example 1. . The spacer was positively charged by spraying, but compared to Example 1, a bead-like spraying state of 2-3 particles was observed.

Example 3 To a mixture of 20 parts by weight of dimethylformamide, 4 parts by weight of methyl methacrylate, and 6 parts by weight of 2-hydroxyethyl methacrylate, 1 part by weight of the spacer base particles 2 obtained in Comparative Example 1 was added. After sufficiently dispersing with a sonicator, the mixture was uniformly stirred. Under a nitrogen atmosphere, 2 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 2N aqueous nitric acid solution was added, and graft polymerization was performed at 40 ° C. for 4 hours.

After the completion of the polymerization, the reaction solution was taken out, and the particles and the reaction solution were separated by a 3 μm membrane filter. After the obtained spacer was sufficiently washed with THF and methanol, it was dried under reduced pressure at room temperature with a vacuum drier.

For the obtained spacer, the particle diameter difference before and after graft polymerization was measured using a Coulter counter in the same manner as in Example 1, and the thickness of the graft polymerization layer was determined.
It was 200Å. When the obtained surface-treated spacer was sprayed in the same manner as in Example 1, a scattered state of single particles was obtained.

In order to confirm the charging polarity of the resin having the same composition as that of the above-mentioned surface treatment layer, a resin for the surface treatment layer was prepared in the same manner as in Example 1, powdered, and sprayed as in Example 1, and charged. When the polarity was confirmed, it was negatively charged.

When the spacers were sprayed in the same manner as described above using a more dry nitrogen gas and a dew point of -73 ° C., a rosary of 2 to 3 particles was observed compared to the above. Next, moisture is added to the nitrogen gas, and the dew point is set to −40.
℃ and sprayed spacers as above,
The scattering state of single particles came to be seen. Next, moisture was further added to the nitrogen gas, the dew point was adjusted to -10 ° C, and the spacers were sprayed in the same manner as described above. As a result, a beaded spraying state of 2 to 3 particles came to be seen.

(Example 4) [Spacer spraying condition] A dry sprayer (DISPA-μR, manufactured by Nisshin Engineering Co., Ltd.) was used, and SU was used as a pipe.
Equipped with S316 (electropolishing product). The pipe was electrically floated from the apparatus housing ground, and installed so as to be grounded via an electrometer. The charge of the spacer between the pipe and the spacer was measured to confirm the charged polarity of the spacer. Nitrogen gas was used as the gas, and the dew point was controlled at -60 ° C. Using this device, Micropearl SPS-2045
(Manufactured by Sekisui Chemical Co., Ltd.) and the number of sprays is about 200
The spraying time and the number of rotations of the feeder were set so that the number of pieces / mm ² was obtained.

[Liquid Crystal Cell Manufacturing Conditions] Rubbing treatment was performed on a pair of glass plates (150 mm × 150 mm) on which a polyimide (Nissan Chemical Industries, SE-7210) alignment film was formed, and spacers were sprayed under the above spraying conditions. , The rubbing direction is set to 180 °, and the sealing agent (main agent: SE4500, curing agent: HAVEN CHEMIC)
(Manufactured by AL Co.). After this, 16
The treatment was performed at 0 ° C. for 90 minutes to cure the sealant, thereby producing an empty cell. After injecting an IPS type liquid crystal (JC-5014, manufactured by Chisso Corporation) into the obtained empty cell, the injection port was closed with an adhesive to prepare a liquid crystal cell, and further heat-treated at 120 ° C. for 30 minutes. The liquid crystal cell obtained in this manner is sandwiched between polarizing films, and a backlight is applied to display unevenness.
Spots and the like were observed.

[Preparation of Spacer 1] 90 parts by weight of divinylbenzene, 10 parts by weight of dimethylaminoethyl methacrylate, and benzoyl peroxide were added to 800 parts by weight of a 3% by weight aqueous solution of polyvinyl alcohol (GH-20, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.). 2 parts by weight of the mixed solution 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.
The obtained particles were washed with hot ion-exchanged water and methanol and subjected to a classification operation to obtain an average particle size of 4.45 μm and a CV value of 3.
0% spacer 1 was obtained. The 10% K value of the spacer 1 was 580 when measured by the above method. When the obtained spacer 1 was sprayed under the above spacer spraying conditions, the number of sprays was about 220 pieces / mm ² , and the charge amount was +9.
The concentration was 0 μC / g, and no aggregation of the spacers and no uneven dispersion were observed. In addition, when the cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, the color tone was uniform, and no display unevenness or spots were observed.

(Example 5) [Preparation of spacer 2] 1 part by weight of 2-hydroxyethyl methacrylate, 2 parts by weight of methacryloyloxyethyl isocyanate, and 0.2 parts by weight of dibutyltin dilaurate were dissolved in 10 parts by weight of THF. The reaction was carried out at 60 ° C. for 5 hours while stirring under a nitrogen atmosphere. The reaction mixture was distilled to obtain a crosslinkable monomer having a carbamoyl group. Polyvinyl alcohol (GH-2, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.)
A mixture of 60 parts by weight of divinylbenzene, 40 parts by weight of the crosslinkable monomer and 2 parts by weight of benzoyl peroxide was added to 800 parts by weight of the 3% by weight aqueous solution of 0), and the mixture was stirred with a homogenizer to adjust the particle size. went. Thereafter, the temperature was raised to 80 ° C. under a nitrogen stream with stirring, and the reaction was carried out for 15 hours.
The obtained particles were washed with hot ion-exchanged water and methanol and subjected to a classification operation to obtain an average particle diameter of 4.33 μm and a CV value of 3.
0% spacer 2 was obtained. The 10% K value of the spacer 2 was 610 as measured by the method described above. When the obtained spacer 2 was sprayed under the above-described spacer spraying conditions, the number of sprays was about 210 pieces / mm ² , and the charge amount was +8.
The concentration was 0 μC / g, and no aggregation of the spacers and no uneven dispersion were observed. In addition, when the cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, the color tone was uniform, and no display unevenness or spots were observed.

(Example 6) [Preparation of untreated spacer 3] 3% by weight aqueous solution of polyvinyl alcohol (GH-20, manufactured by Nippon Synthetic Chemical Industry) 80
A mixture of 70 parts by weight of divinylbenzene, 20 parts by weight of acrylonitrile, 10 parts by weight of 2-hydroxyethyl methacrylate, and 2 parts by weight of benzoyl peroxide was added to 0 parts by weight, 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 while stirring,
The reaction was performed for 15 hours. The obtained particles were washed with hot ion-exchanged water and methanol and then classified to obtain an untreated spacer 3 having an average particle size of 4.29 μm and a CV value of 3.0%. The 10% K value of the untreated spacer 3 was 660 as measured by the method described above.

[Introduction of Amino Group, etc., Production of Spacer 4]
While irradiating ultrasonic waves to 100 parts by weight of dehydrated THF, 10 parts by weight of the untreated spacer 3 and 0.2 parts by weight of dibutyltin dilaurate were uniformly dispersed. While stirring this dispersion under a nitrogen atmosphere, 10 parts by weight of lauryl isocyanate was added dropwise and reacted at 60 ° C. for 5 hours. After the reaction, the spacer was collected by filtration, dispersed again in 100 parts by weight of THF, and washed. This operation was repeated several times, and the spacer was sufficiently washed and dried in vacuum. When the obtained spacer 4 was sprayed under the above-described spacer spraying conditions, the number of sprays was about 200.
Pcs / mm ² , the charge amount was +65 μC / g, and almost no aggregation or uneven dispersion of the spacer was observed. Also,
When a cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, the color tone was uniform as in Example 4, and no display unevenness or stain was observed. Also, light leakage around the spacer was smaller than in the case where SPS-2045 was used.

(Comparative Example 2) When the untreated spacer 3 obtained in Example 6 was directly sprayed under the above-mentioned spacer spraying conditions, the spraying number was as small as about 50 pieces / mm ^2, and the charge amount was +10 μC / g. And large cohesion and uneven dispersion were observed in some places. In addition, when a cell was manufactured in accordance with the above-described liquid crystal cell manufacturing conditions, display unevenness and spots were confirmed.

(Example 7) [Production of surface-treated spacer 5] 40 parts by weight of dimethylformamide, 6 parts by weight of lauryl methacrylate, 14 parts by weight of methyl methacrylate, 2 parts by weight of acrylamide and the untreated material obtained in Example 6 After adding 2 parts by weight of the spacer 3 and sufficiently dispersing it with a sonicator, the mixture was uniformly stirred. Nitrogen gas was introduced into the system, and 5 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution adjusted with a 2N aqueous nitric acid solution was added thereto, followed by reaction at 50 ° C. for 8 hours. After the completion of the polymerization reaction, take out the reaction solution, 3 μm
The particles were collected by a membrane filter. The spacer was sufficiently washed with THF and methanol in the same manner as in Example 5, and then dried under vacuum. When the obtained spacer 5 was sprayed under the above-described spacer spraying conditions, the number of sprays was about 210
Pcs / mm ² , the charge amount was +80 μC / g, and no aggregation of the spacers and no uneven dispersion were observed. In addition, when the cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, the color tone was uniform as in Example 4, and no display unevenness or stain was observed. In addition, light leakage around the spacer is also SPS-2.
045 was smaller.

(Example 8) [Preparation of surface-treated spacer 6] 1 part by weight of 2-hydroxyethyl methacrylate, 2 parts by weight of lauryl isocyanate, and 0.2 part by weight of dibutyltin dilaurate were added to TH.
F10 parts by weight and stirred under a nitrogen atmosphere.
The reaction was performed at 0 ° C. for 5 hours. The reaction mixture was distilled to obtain a polymerizable monomer having a carbamoyl group. This polymerizable monomer (4 parts by weight), dimethylformamide (40 parts by weight), lauryl methacrylate (6 parts by weight), methyl methacrylate (14 parts by weight), and 2 parts by weight of the untreated spacer 3 obtained in Example 6 were added. Surface treatment was carried out in the same manner as in Example 7 to obtain a spacer 6. When the obtained spacers 6 were sprayed under the above-described spacer spraying conditions, the number of sprays was about 210 pieces / m.
m ² , the charge amount was +75 μC / g, and almost no coagulation of spacers or uneven dispersion was observed. Further, when the cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, the color tone was uniform as in Example 4, and no display unevenness or spots were observed. In addition, light leakage around the spacer is also SPS-
2045 was smaller.

(Comparative Example 3) [Preparation of untreated spacer 7] An untreated spacer 7 was obtained in the same manner as in Example 6, except that 2 parts by weight of acrylamide was not added. When the untreated spacer 7 was sprayed under the above-described spacer spraying conditions, the spraying number was as small as about 120 pieces / mm ² , the charge amount was +50 μC / g, and rosary-like aggregation and scattering unevenness were observed in some places. Was. When a cell was manufactured in accordance with the above-described liquid crystal cell manufacturing conditions, light leakage around the spacer was almost the same as in Example 7, but slight display unevenness and stains were confirmed.

(Example 9) [Preparation of surface-treated spacer 8] 40 parts by weight of dimethylformamide, 6 parts by weight of lauryl methacrylate, 14 parts by weight of methyl methacrylate, 2 parts by weight of 2-hydroxyethyl methacrylate, and Example 6 2 parts by weight of the untreated spacer 3 obtained in the above was added and the surface treatment was carried out in the same manner as in Example 7 to obtain a spacer 8.

[Introduction of Amino Group and the Like into Spacer 8] A carbamoyl group was introduced into the obtained spacer 8 with lauryl isocyanate in the same manner as in Example 6 to obtain a spacer 9. When the spacers 9 were sprayed under the above-described spacer spraying conditions, the number of sprays was about 220 pieces / mm ² , the charge amount was +90 μC / g, and aggregation of the spacers and unevenness in spraying were hardly observed. In addition, when the cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, the color tone was uniform as in Example 4, and no display unevenness or stain was observed.
Also, light leakage around the spacer was smaller than in the case where SPS-2045 was used.

(Comparative Example 4) When the spacer 8 obtained in Example 9 was sprayed as it was under the above spacer spraying conditions, the number of sprays was as small as about 100 pieces / mm ² and the charge amount was +.
It was 30 μC / g, and aggregation and scattering unevenness were observed in some places. When a cell was manufactured according to the above-described liquid crystal cell manufacturing conditions, light leakage around the spacer was almost the same as in Example 7, but display unevenness and stains were confirmed.

[0101]

According to the present invention having the above-described structure, the spacers can be evenly sprayed on the substrate in a single particle state by the dry spraying method without causing poor spreading such as aggregation of the spacers and insufficient number of sprays. This makes it possible to reduce the spacer dispersion defect in the production of the liquid crystal display device and improve the yield, and at the same time, it is possible to obtain a liquid crystal display device free from display defects such as display unevenness and spots.

[Brief description of the drawings]

FIG. 1 is a diagram showing an outline of a liquid crystal display device.

FIG. 2 is a diagram showing an outline of a dry sprayer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polarizer 2 Black matrix 3 Color filter 4 Overcoat 5 Alignment film 6 Transparent electrode 7 Substrate 8 Liquid crystal 9 Spacer 10 Sprayer main body 11 Piping 12 Spacer metering (supply) feeder 13 Stage

Claims (9)

[Claims] 1. A spacer for a liquid crystal display having a surface treatment layer made of a thermoplastic resin formed on the surface of a spacer base particle, wherein the spacer base particle and the spacer base particle are dispersed by a dry dispersion method. The surface treatment layer is a spacer for a liquid crystal display device, which is charged to the same polarity. 2. A spacer for a liquid crystal display in which a surface treatment layer made of a thermoplastic resin is formed on the surface of a spacer base particle, wherein the spacer base particle and the spacer base particle are sprayed by a dry spray method. The surface treatment layer is a spacer for a liquid crystal display device, which is charged to a different polarity and has a thickness of 250 ° or more. 3. It is characterized in that it is positively charged by being sprayed by a dry spraying method, and has an amino group or a group containing a structure represented by the following general formula (1) on at least its surface. For liquid crystal display devices. Embedded image 4. The spacer for a liquid crystal display device according to claim 3, wherein a surface treatment layer made of a thermoplastic resin is formed on the surface of the spacer base particles. 5. The dew point of the gas used for dry spraying is -75 to
5. The spacer for a liquid crystal display device according to claim 3, wherein the charge amount at -50 [deg.] C. is 60 [mu] C / g or more. 6. A method for spraying a spacer for a liquid crystal display device according to claim 1, 2, 3, 4, or 5, wherein the spacer for a liquid crystal display device is sprayed by a dry spraying method. A method of spraying spacers for a liquid crystal display device, characterized in that the pipe is positively charged and the dew point of gas used for dry spraying is -75 to -50 ° C. 7. A method for spraying a spacer for a liquid crystal display device according to claim 1 or 2, wherein the spacer for a liquid crystal display device is sprayed by a dry spraying method. A method for spraying a spacer for a liquid crystal display device, wherein the charged gas has a dew point of −60 to −20 ° C. used for dry spraying. 8. A liquid crystal display device using the spacer for a liquid crystal display device according to claim 1, 2, 3, 4, or 5. 9. A method for manufacturing a liquid crystal display device according to claim 8, comprising a spacer dispersing step using the method for dispersing spacers for a liquid crystal display device according to claim 6 or 7. Manufacturing method.