JP2000347193A - Liquid crystal display element spacer and liquid crystal display element - Google Patents

Abstract

(57) [Summary] (Modifications) [PROBLEMS] To provide a liquid crystal display device having high quality display performance without adversely affecting the liquid crystal such as disturbing the alignment of the liquid crystal even when an impact is applied to the liquid crystal display device. Spacer, and
A liquid crystal display device using the spacer is provided. A spacer used in a liquid crystal display element, wherein the spacer is filled in a column and used as a stationary phase,
The solubility parameter is 8.5 to 23.5 (cal / cm
³ ) In the elution peak shape obtained when liquid crystal molecules are flown into a system using the liquid as the mobile phase, the retention time of the elution peak is t (min), and the peak at 50% of the elution peak height is the peak. When the width is W _1/2 (minute), the column length used for the measurement is L (mm), and the average particle size of the liquid crystal display element spacer filled in the column is D (mm), the following formula (1) is used. A spacer having a parameter (P value) of 25 or more. P value = (t / W _1/2 ) ² × D / L (1)

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 spacer for a liquid crystal display device.

[0002]

2. Description of the Related Art In general, a liquid crystal display element has a substrate on which an alignment film, a transparent electrode, etc. are formed, opposed to each other at a predetermined interval via a spacer, and the periphery thereof is sealed with a sealing material.
It is manufactured by injecting liquid crystal into the gap and sealing the inlet.

In this liquid crystal display device, the spacer is 2
It is used to keep the distance between two substrates constant,
The spacer is required to be chemically stable in the liquid crystal, not to disturb the alignment of the liquid crystal, not to move, and the like.

Conventionally, in this type of liquid crystal display device, the orientation of liquid crystal molecules may be irregular at the interface between the liquid crystal and the spacer. When such an abnormal orientation occurs, when the liquid crystal display element is turned on and operated, a phenomenon called so-called light leakage in which light from the backlight is transmitted occurs. For this reason, it is known that the contrast of the liquid crystal display element is reduced and display quality may be impaired.

[0005] Further, light leakage due to such an abnormal orientation tends to occur and increase particularly when a strong shock is applied to the liquid crystal display element screen. Because the light leak does not disappear,
This significantly reduces the contrast of the liquid crystal display element, which is a serious problem.

Several methods have been proposed to eliminate such an abnormal orientation.
No. 19 discloses a spacer in which a layer having an alkyl group is formed on the surface by coating the surface of the fine particles with a silane coupling agent having an alkyl group in order to prevent abnormal alignment of the liquid crystal. .

However, even with such a spacer having an alkyl group introduced on its surface, if a strong impact is given to the screen of the liquid crystal display device, light may escape from around the spacer. If light escape occurs in many spacers existing in the pixel, the contrast of the liquid crystal display element is significantly reduced, and display quality is impaired.

Although the phenomenon of light leakage after the application of an impact has not yet been clearly elucidated, one of the causes is that when a liquid crystal display element is subjected to an impact, the spacer surface and the liquid crystal vibrate violently, It is considered that this mechanical impact changes or destroys the surface molecular structure and fluctuates the hydrophobicity of the surface layer. This structural change is more likely to occur as the density of the hydrophobic portion on the surface is lower, and when the surface layer contains a hydrophilic portion such as a hydroxyl group, the hydrophobicity of the surface is further greatly changed. As a result, it is considered that the alignment of the liquid crystal molecules is disturbed at the interface between the liquid crystal and the spacer, and light leakage is generated and increased. Therefore, there is a need for a liquid crystal display element spacer in which the liquid crystal around the spacer does not exhibit abnormal alignment even when the liquid crystal display element is subjected to an impact.

[0009]

SUMMARY OF THE INVENTION In view of the above situation, the present invention provides a liquid crystal having a high quality display performance without adversely affecting the liquid crystal, such as disturbing the alignment of the liquid crystal even when a shock is applied to the liquid crystal display element. It is an object to provide a spacer for a liquid crystal display element from which a display element can be obtained, and a liquid crystal display element using the spacer for a liquid crystal display element.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a spacer for a liquid crystal display element used for a liquid crystal display element, wherein the spacer for a liquid crystal display element is filled in a column and used as a stationary phase, and the solubility parameter is 8. 5 to 23.5 (cal / c
m ³ ) In the elution peak shape obtained when liquid crystal molecules are introduced into a system using a liquid as the mobile phase, the retention time of the elution peak is t (min), and the retention time of the elution peak is 50% of the height. When the peak width is W _1/2 (minute), the column length used for measurement is L (mm), and the average particle diameter of the liquid crystal display element spacer filled in the column is D (mm), the following formula (1) is used. ) Is a spacer for a liquid crystal display element having a parameter (P value) of 25 or more. P value = (t / W _1/2 ) ² × D / L (1) Hereinafter, the present invention will be described in detail.

In the spacer for a liquid crystal display element of the present invention, the above-mentioned spacer for a liquid crystal display element is filled in a column and used as a stationary phase, and has a solubility parameter of 8.5 to 23.5 (c).
al / cm ³ ), the P value is 25 or more in the elution peak shape obtained when liquid crystal molecules are introduced into a system using a liquid as the mobile phase.

The P value, which is a parameter of the present invention, is obtained from the above equation (1), where t is the time from the injection of liquid crystal molecules until the peak top of the elution peak elutes, and W _1/2 is the elution peak. Shows the peak width at the 50% part, that is, the half width. (T / W _1/2 ) ² in the above formula (1) is a term proportional to the number of theoretical plates indicating the sharpness of the elution peak. D indicates the average particle size of the liquid crystal display element spacer filled in the column. Generally, the larger the D, the smaller the theoretical plate number, and the smaller the D, the larger the theoretical plate number. Also,
L indicates the length of the column used for the measurement. As L increases, the number of theoretical plates increases, and as L decreases, the number of theoretical plates decreases. Usually, the number of theoretical plates is an index affected by D and L, but the P value in the present invention is a parameter obtained by correcting the sharpness of the elution peak with the average particle size and the column length, and the liquid crystal display filled in the column is used. This indicates the degree of resolution of the elution peak possessed by the particle itself, irrespective of the average particle diameter of the element spacer and the column length.

The present inventors used a liquid crystal display element spacer packed in a column as a stationary phase and used a liquid having a solubility parameter of 8.5 to 23.5 (cal / cm ³ ) as a mobile phase. In the elution peak shape obtained when liquid crystal molecules were introduced into the system, it was found that a spacer for a liquid crystal display element having the above-mentioned P value of 25 or more did not cause abnormal alignment even when an impact was applied.

That is, when liquid crystal molecules are introduced into a column filled with the above-mentioned spacer for a liquid crystal display element, the liquid crystal molecules dissolved in the mobile phase are mixed with the hydrophobic portion existing on the surface of the spacer filled in the column. Flows toward the column end together with the mobile phase while repeating adsorption and desorption by hydrophobic interaction between the two. The linear velocities of the individual liquid crystal molecules in the column are relatively slower than the linear velocities of the mobile phase because they are held on the stationary phase by hydrophobic interaction. Therefore, the liquid crystal molecules become elution peaks and are detected on the chromatogram. The retention time becomes longer as the retention force becomes stronger, and the retention time becomes shorter as the retention force becomes smaller. At this time, between the individual liquid crystal molecules and the spacer surface, if the rate of adsorption and desorption is fast and there is no large difference between the individual, the elution peak becomes sharp, but the rate of adsorption and desorption is slow, and If there is individual variation, the elution peak becomes broad.

At this time, the rate of adsorption and desorption greatly depends on the density of the hydrophobic portions on the spacer surface. If the hydrophobic portions on the spacer surface are dense, desorption of liquid crystal molecules is performed only on the very surface of the spacer. Therefore, the adsorption / desorption speed increases,
As the hydrophobic portion is rougher, the liquid crystal molecules penetrate deeper into the surface of the spacer, and the adsorption / desorption speed becomes slower. as a result,
The resulting elution peak becomes broad and lowers the P value.

When a hydrophilic portion such as a hydroxyl group is contained in the spacer surface layer, a part of liquid crystal molecules causes abnormal desorption, and the rate of adsorption and desorption of individual liquid crystal molecules varies. The resulting eluting peak becomes broad and also reduces the P value.

When the liquid crystal display element receives an impact, the surface of the spacer and the liquid crystal vibrate violently, and the mechanical impact changes or destroys the surface molecular structure and changes the hydrophobicity of the surface layer, thereby causing the orientation of the liquid crystal to change. Of the light, causing light leakage. Such a structural change is more likely to occur as the density of the hydrophobic portion on the surface is lower, and when the surface layer contains a hydrophilic portion such as a hydroxyl group, the influence is more likely to occur. For this reason, it is considered that the spacer for a liquid crystal display element having a low P value causes disorder in the alignment of liquid crystal molecules at the interface between the liquid crystal and the spacer, and easily causes and increases light leakage.

The rate of adsorption and desorption of liquid crystal molecules on the spacer surface in the column is affected not only by the hydrophobic density of the surface layer and the hydrophilic portion exposed on the outermost surface of the spacer, but also by the composition near the surface. Conceivable. For this reason, even if the hydrophilic portion is not exposed on the surface, the hydrophilic portion that is changed or exposed due to vibration or the like also reduces the sharpness of the elution peak, thereby lowering the P value. When such a spacer is used in a liquid crystal display device, the impact similarly disturbs the alignment of the liquid crystal around the spacer, causing and increasing light leakage.
In addition, the "stable" hydrophilic portion, which does not change or expose due to vibration, does not affect the rate of adsorption and desorption of liquid crystal molecules. Does not increase. The density of the hydrophobic portion on the particle surface described above can be relatively compared by a known analysis method such as TOF-SIMS or pyrolysis GC.

When a liquid crystal display element spacer having a P value of less than 25 is used for a liquid crystal display element, the performance of preventing abnormal alignment is not sufficient, and light leakage occurs around the spacer from the beginning, or the initial state is abnormal. Even if it does not cause orientation, it gives off light around the spacer by giving an impact,
The quality of the liquid crystal display element is deteriorated. On the other hand, when a liquid crystal display element having a liquid crystal display element having a P value of 25 or more according to the present invention is used, even if the liquid crystal display element is subjected to impact, the alignment state of the liquid crystal does not become irregular and abnormal. The liquid crystal display element does not have an adverse effect such as light leakage due to alignment.

The liquid used for the mobile phase is not particularly limited as long as it has a solubility parameter of 8.5 to 23.5 (cal / cm ³ ). For example, water, methanol, ethanol, n-propanol, i -Butanol, acetonitrile, tetrahydrofuran and the like. Liquids having such a solubility parameter may be used alone or in combination of two or more. If the solubility parameter of the liquid used for the mobile phase is less than 8.5 (cal / cm ³ ),
The hydrophobic interaction between the liquid crystal display element spacer and the liquid crystal molecules is reduced, making the measurement difficult. On the other hand, when the solubility parameter exceeds 23.5 (cal / cm ³ ), the hydrophobic interaction becomes too strong, and the liquid crystal molecules are irreversibly adsorbed and cannot be obtained as an elution peak. The solubility parameter is an amount defined by (ΔE ^V / V) ^1/2 . Here Delta] E ^V is the molar vaporization energy of the liquid, V is the molar volume.

Examples of the spacer for a liquid crystal display element having the above-mentioned properties include those having a functional group exhibiting a hydrophobic interaction with liquid crystal introduced on the surface. The functional group showing a hydrophobic interaction with the liquid crystal is not particularly limited, for example, lauryl group, methyl group, ethyl group, cetyl group, stearyl group, butyl group, hexyl group, octyl group, behenyl group, isobutyl group, isobutyl group, alkyl groups such as t-butyl group, phenyl group, t-butylphenyl group, isobornyl group, norbornyl group and adamantyl group; and acyl groups such as octanoyl group, lauroyl group, myristoyl group, palmitoyl group and stearoyl group.

As a method for introducing the above functional group onto the surface of the spacer for a liquid crystal display element, for example, after impregnating the surface of the spacer having a reducing group with the polymerizable monomer having the above functional group, a cerium salt, a permeate A radical is generated on the surface of the spacer by reacting an oxidizing agent such as a sulfate,
A method of forming a graft polymerization layer on the surface of the spacer starting from the above radicals and the like can be mentioned.

The polymerizable monomer having the above functional group is not particularly limited. For example, lauryl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, stearyl (meth) acrylate, cetyl (meth) Acrylate, butyl (meth) acrylate,
Hexyl (meth) acrylate, octyl (meth) acrylate, behenyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, phenyl (meth) acrylate, t-butylphenyl (meth) acrylate, isobornyl (meth) A) acrylate, norbornyl (meth) acrylate, adamantyl (meth) acrylate, vinyl octanoate, vinyl laurate, vinyl myristate, vinyl palmitate, vinyl stearate and the like. These polymerizable monomers having a functional group may be used alone or in combination of two or more.

Further, a method of introducing a polymerizable monomer having a reactive group on the surface of the spacer and then reacting the compound having the functional group with the above-mentioned method may be used. The polymerizable monomer having a reactive group is not particularly limited, for example, a carboxyl group, a hydroxyl group, an amino group, an amide group, an epoxy group,
A polymerizable monomer having a reactive group such as a sulfone group, a mercapto group, and an isocyanate group; a vinyl monomer that generates the above-described reactive group by means such as hydrolysis, addition, condensation, and ring opening; Is mentioned. Specifically, for example,
(Meth) acrylic acid, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, glyceroyl (meth) acrylate, (meth) acrylamide, dimethylaminopropyl (meth) acrylate, polyethylene Glycol (meth) acrylate and the like. These polymerizable monomers having a reactive group may be used alone or in combination of two or more.

The compound having a functional group is not particularly limited, and examples thereof include carboxylic acids, halides and salts thereof; alcohols; sulfonic acids, halides and salts thereof, and amines. These compounds having a functional group may be used alone or in combination of two or more. By using such a method, a functional group having a hydrophobic interaction with the liquid crystal can be introduced to the surface of the spacer.

The material of the fine particles used for manufacturing the spacer for a liquid crystal display device of the present invention is not particularly limited, and may be an inorganic material or 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.

However, when an inorganic material is used as the material of the fine particles, the coefficient of thermal expansion is greatly different from that of the liquid crystal, so that it cannot follow the temperature change and may cause a defect such as low-temperature foaming. Therefore, it is preferable to use an organic material whose coefficient of thermal expansion does not largely differ from that of the liquid crystal.

The organic material is not particularly limited, but a polymer of a polymerizable monomer having an ethylenically unsaturated group is preferably used. Further, since the fine particles function as core particles of the liquid crystal display device spacer of the present invention,
Considering its mechanical strength, it is a fine particle obtained by polymerizing a polymerizable monomer having an ethylenically unsaturated group, and the polymerizable monomer having the ethylenically unsaturated group is at least 20% by weight. Is preferably a polymerizable monomer having two or more ethylenically unsaturated groups.

The organic material is not particularly restricted but includes, for example, epoxy resins, phenol resins, melamine resins,
And unsaturated polyester resins. However, considering its mechanical strength, it is a fine particle obtained by polymerizing a monomer having an ethylenically unsaturated group, and the polymerizable monomer having the ethylenically unsaturated group is at least 20% by weight. Is preferably a polymerizable monomer having two or more ethylenically unsaturated groups.

The polymerizable monomer having two or more ethylenically unsaturated groups is not particularly restricted but includes, for example, tetramethylolmethanetetra (meth) acrylate, tetramethylolmethanetri (meth) acrylate, tetramethylolmethane Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate, glycerol di (meth) acrylate, polyethylene glycol di Polyfunctional (meth) acrylates such as (meth) acrylate and polypropylene glycol di (meth) acrylate; triallyl (iso) cyanurate, triallyl trimellitate and the like;
Examples include divinylbenzene, diallyl phthalate, diallyl acrylamide and the like.

The fine particles may be composed of only the polymerizable monomer having two or more ethylenically unsaturated groups, or may be a polymerizable monomer having two or more ethylenically unsaturated groups. It may be obtained by copolymerizing a polymerizable monomer having another ethylenically unsaturated group with a polymerizable monomer having an ethylenically unsaturated group. The other polymerizable monomers are not particularly limited, and include, for example, styrene monomers such as styrene and α-methylstyrene, and (meth) acrylates such as methyl (meth) acrylate. The polymerizable monomer having two or more ethylenically unsaturated groups and the other polymerizable monomer having an ethylenically unsaturated group may be used alone or in combination of two or more.

The mechanical strength of the spacer for a liquid crystal display device of the present invention preferably has a 10% K value of 2500 to 15000. If it is less than 2500, the strength of the particles is not sufficient, so that the spacer is broken when assembling the liquid crystal display device, and it is difficult to form an appropriate gap. Further, when packing the column, the particles may be crushed by the pressure at the time of packing. 1500
If it exceeds 0, low-temperature foaming may occur when incorporated into a display device.

In the present specification, the 10% K value is defined as a diamond cylinder having a diameter of 50 μm using a micro compression tester (PCT-200, manufactured by Shimadzu Corporation) according to Japanese Patent Application Laid-Open No. 6-503180. Is a value obtained by compressing the fine particles of the spacer obtained on the smooth end face with a compression hardness of 0.27 g / sec and a maximum test load of 10 g, and calculating from the following equation. K = (3 / √2) ・^FS -3 / 2 ・ R- ¹ / ² (N / mm ² ) F: Load value at 10% compressive deformation of fine particles (N) S: 10% compressive deformation of fine particles Compression displacement at (mm) R: radius of fine particles (mm)

The shape of the spacer for a liquid crystal display element is not particularly limited, and may be, for example, a sphere, an ellipse sphere, a column, or the like. A sphere is preferable for filling a column and measuring a P value. When the shape of the spacer for a liquid crystal display element is spherical, the particle size is preferably 0.1 to 100 μm, and more preferably 1 to 10 μm. The spacer for a liquid crystal display element of the present invention may be colored by various known methods.

The spacer for a liquid crystal display element of the present invention preferably has a long-chain alkyl group having 4 to 22 carbon atoms on its surface, and more preferably has 8 to 22 carbon atoms, from the viewpoint of preventing abnormal alignment.
More preferably, it has a long-chain alkyl group of 22. When a liquid crystal display element spacer having these alkyl groups is used for a liquid crystal display element, it is known that liquid crystal molecules are vertically aligned to suppress light leakage,
At the same time, it is considered that the compound has a function of inhibiting the adsorption of the liquid crystal molecules to the hydrophilic portion under the influence of the long hydrophobic chain.

The liquid crystal display element spacer of the present invention having such a structure does not adversely affect the liquid crystal such as disturbing the alignment of the liquid crystal. Further, the spacer for a liquid crystal display element of the present invention can be suitably used for a liquid crystal display element. The liquid crystal display element will be described with reference to FIG.

As shown in FIG. 1, the above-mentioned liquid crystal display element has a polarizing sheet 1 provided on one surface, and an insulating film 3, a transparent electrode 4 and an alignment film 5 sequentially provided on a surface opposite to the surface provided with the polarizing sheet 1. A pair of transparent substrates 2 stacked and arranged so that the alignment films 5 face each other, and a liquid crystal injected between the alignment films 5 and the liquid crystal display element spacers 7 held between the facing alignment films 5. 6, and a sealing material 8 formed on the periphery.

The above-mentioned liquid crystal display element can be manufactured, for example, by the following method. First, an insulating film 3 made of SiO ₂ or the like is formed on a surface of the two transparent substrates 2 on which the polarizing sheet 1 is provided on one surface and on a surface opposite to the surface on which the polarizing sheet 1 is provided. A transparent electrode 4 made of ITO or the like is patterned by photolithography. Thereafter, an alignment film 5 made of polyimide or the like is formed on each transparent electrode 4, and a spacer 7 for a liquid crystal display element is sprayed on the alignment film 5 of one transparent substrate 2.

Thereafter, the substrate on which the spacers 7 for the liquid crystal display element are sprayed is replaced with the substrate on which the other spacers are not sprayed.
The alignment film 5 is disposed so as to face the substrate, an adhesive layer is formed around the substrate using a sealing material 8 around the substrate, and a substrate on which spacers for liquid crystal display elements are scattered and a substrate on which spacers are not scattered. And a liquid crystal 6 is injected between these substrates to produce a liquid crystal cell, and wiring is provided in the obtained liquid crystal cell to produce a liquid crystal display element 10.

When the liquid crystal display element spacers are sprayed on the substrate, the spray density is 10 to 1000 pieces / mm.
² is preferred. If the scatter density is less than 10 cells / mm ² , the gap of the liquid crystal cell may not be uniform, and if the scatter density exceeds 1000 cells / mm ² , the contrast of the liquid crystal display element decreases due to the presence of the spacer for the liquid crystal display element. May be. The liquid crystal display device having such a configuration has high-quality display performance. The above liquid crystal display device is also one of the present invention.

Since the liquid crystal display element of the present invention uses the spacer for a liquid crystal display element of the present invention, the liquid crystal around the spacer hardly causes abnormal alignment even when subjected to an impact, and has high quality display performance. is there.

[0042]

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) 3% aqueous solution of polyvinyl alcohol 8
A mixture of 50 parts by weight of divinylbenzene, 50 parts by weight of tetramethylolmethanetetraacrylate, and 3 parts by weight of benzoyl peroxide was added to 00 parts by weight, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. by a stream of nitrogen while 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 resulting fine particles had an average particle size of 5.2 μm, a CV value of 3%, and a 10% K value of 5600 N /
mm ² .

(Surface Treatment of Fine Particles) To a separable flask were added 10 parts by weight of the fine particles prepared as described above, 50 parts by weight of ion-exchanged water, and 30 parts by weight of hydroxyethyl methacrylate, followed by stirring. Next, nitrogen gas was introduced into the system, and the mixture was stirred at 50 ° C. for 5 hours. To this, 20 parts by weight of a 0.1 mol / L ceric ammonium nitrate solution prepared 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 through a membrane filter having a pore size of 3 μm. The obtained fine particles were washed with methanol and acetone, and dried under reduced pressure with a vacuum drier.

After drying, 10 parts by weight of fine particles were dispersed in 100 parts by weight of tetrahydrofuran, and triethylamine 4
0 parts by weight were added. After a mixture of 10 parts by weight of myristic acid chloride and 10 parts by weight of acetyl chloride was added dropwise under nitrogen reflux, the mixture was reacted at 60 ° C. for 3 hours. After completion of the reaction, the particles and the reaction solution were separated by filtration with a membrane filter having a pore size of 3 μm. The obtained particles were washed with methanol and tetrahydrofuran several times each, and then dried under reduced pressure using a vacuum drier to obtain a surface-treated spacer for a liquid crystal display element. The P value of the elution peak of the liquid crystal molecule was measured by the following evaluation method using the obtained spacer as a stationary phase. Further, the obtained spacer was observed for light leakage according to the method for evaluating abnormal liquid crystal orientation described below. The results are shown in Table 1.

<Evaluation method> (Measurement of P value)
The resulting liquid crystal display element spacer was filled in this column while flowing n-propanol at a constant pressure (20 MPa) using a HPLC (high performance liquid chromatography) pump, and used as an evaluation column. The liquid crystal molecules 5CB and PTP- represented by the following structural formulas (1) and (2)
0.01 mol of each of n-propanol 1
The sample was dissolved in 000 mL to obtain a measurement sample.

The obtained measurement sample was analyzed by the liquid chromatography apparatus shown in FIG. 2 under the following measurement conditions.
In the liquid chromatography apparatus 20, the liquid sending pump 22
The measurement sample is automatically injected by the autosampler 23 into the mobile phase 21 sent by the above. Thereafter, the measurement sample and the mobile phase 21 are sent to the spacer packed column 24, and are further detected by the ultraviolet ray detector 25, so that the recorder 2
In step 6, a chromatogram can be obtained. The P value at the elution peak of the liquid crystal molecules can be calculated from the obtained chromatogram. In all the columns used for the P value measurement, the fitting on the column-in side was removed, and it was confirmed that no gap was generated at the column entrance.

[0048]

Embedded image

(Column size) Column (1) Inner diameter 6 mm, length 75 mm Column (2) Inner diameter 6 mm, length 150 mm

The measurement conditions were as follows. (1) Mobile phase The following three types of mobile phases (1) to (3) were used as mobile phases. 13. Mobile phase (1) Methanol (solubility parameter;
5): water (solubility parameter; 23.4) = 1: 1 mobile phase (2) acetonitrile (solubility parameter; 1)
1.9): Water = 1: 1 Mobile phase (3) Tetrahydrofuran (solubility parameter: 9.1): Water = 1: 1 (2) Flow rate 1 mL / min (3) Column temperature 40 ° C. (4) UV detection Used wavelength 280nm

(Evaluation of Liquid Crystal Abnormal Alignment) The coordination of the liquid crystal was determined to be STN type liquid crystal display device, TN type liquid crystal display device, IP
The following (1) to (1) to serve as indices of the S-type liquid crystal display device
The three-mode liquid crystal display device of (3) was manufactured and evaluated. The evaluation was performed in three stages of ○, Δ, and ×, and each was evaluated as follows. ；: Little or no light leakage Δ: slight light leakage ×: significant light leakage

[0052] (1) on one side of the STN mode cell pair of transparent glass plates (150 mm × 150 mm), after depositing the SiO ₂ film by a CVD method, SiO ₂
A polyimide intermediate (LP-64, manufactured by Toray Industries, Inc.) is formed by spin coating on a glass substrate with an ITO film obtained by forming an ITO film on the entire surface of the film by sputtering, and baking at 280 ° C. for 90 minutes. Thus, a polyimide alignment film was formed. After this glass plate was subjected to a rubbing treatment, a synthesized spacer was placed on the side of the alignment film of one of the above substrates by using a dry sprayer (DISPA-μR, manufactured by Nisshin Engineering Co., Ltd.) by 1 mm ^2. 100 per
Sprayed to ~ 200. A peripheral sealing agent (main agent: SE4500, curing agent: HAV) is provided around the other substrate.
EN CHEMICAL Co., Ltd.), the rubbing direction (twist angle) was arranged so as to oppose to 240 °, and the two were bonded to each other. Produced. After injecting STN type liquid crystal (S-811 manufactured by Merck) into the obtained empty cell, the injection port is closed with an adhesive to prepare a liquid crystal cell.
Further, heat treatment was performed at 120 ° C. for 30 minutes.

The thus obtained STN mode liquid crystal cell was sandwiched between two polarizing films so as to be in a normally black display mode, and the degree of light leakage was observed with a microscope while applying a voltage of about 5V. Subsequently, the edge of the liquid crystal cell was strongly hit 100 times with a rubber mallet to give an impact, and the degree of light leakage around the spacer was similarly observed.

(2) TN mode cell A polyimide alignment film (manufactured by Nissan Chemical Industries, Ltd., SE-7210) was arranged on a pair of transparent glass plates with an ITO film obtained in the same manner as in the STN cell by the spin coating method. After baking, a rubbing treatment was performed. Next, the synthesized spacer was sprayed in the same manner as the STN cell, and the rubbing direction was 9
They were arranged facing each other so as to be at 0 °, and were bonded together using the same sealant. Thereafter, treatment was performed at 160 ° C. for 90 minutes to cure the sealing material, thereby producing an empty cell. In the obtained empty cell, a TN type liquid crystal (MLC-622, manufactured by Merck & Co.)
After injecting 2), 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 arranged in a cross nicol so as to be in a normally white display mode, and a voltage of 7 V is applied to the liquid crystal cell using a microscope in the same manner as in the STN mode liquid crystal cell. The degree of light leakage before and after the application was observed.

(3) IPS mode cell A rubbing treatment is performed on a pair of glass plates without an ITO film on which a polyimide alignment film is formed in the same manner as in the TN cell, and the synthesized spacer is dispersed in the same manner as in the STN cell. Then, they were arranged facing each other so that the rubbing direction was 180 °, and they were bonded together using the same sealing agent. Thereafter, the sealing material is cured by treating at 160 ° C. for 90 minutes,
An empty cell was prepared. In the obtained empty cell, an IPS type liquid crystal containing no chiral agent (MLC-660, manufactured by Chisso Corporation) was used.
After injecting 1), 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 thus obtained is sandwiched between polarizing films arranged in crossed Nicols so as to be in a normally black display mode, and before and after the application of an impact using a microscope with no voltage applied, similarly to the STN cell. The degree of light leakage was observed.

Example 2 A spacer for a liquid crystal display device was obtained in the same manner as in Example 1 except that stearic acid chloride was used instead of myristate chloride. The P value of the elution peak of the liquid crystal molecule was measured by the same evaluation method as in Example 1 using the obtained spacer as a stationary phase. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 3 (Preparation of fine particles) 3% aqueous solution of polyvinyl alcohol 8
A mixture of 30 parts by weight of divinylbenzene, 70 parts by weight of tetramethylolmethanetetraacrylate, and 3 parts by weight of benzoyl peroxide was added to 00 parts by weight, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. by a stream of nitrogen while 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 resulting fine particles had an average particle size of 4.0 μm, a CV value of 3%, and a 10% K value of 6300 N /
mm ² .

(Surface treatment of fine particles) In a separable flask, 10 parts by weight of the fine particles prepared by the above operation, 50 parts by weight of ion-exchanged water, 10 parts by weight of lauryl methacrylate, 5 parts by weight of methyl methacrylate, 5 parts by weight of isobornyl methacrylate Was added and stirred. Next, nitrogen gas was introduced into the system, and stirring was continued at 30 ° C. for 3 hours. to this,
A 0.1 mol / L ceric ammonium nitrate solution 10 prepared 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 through a membrane filter having a pore size of 3 μm. The obtained fine particles were sufficiently washed with tetrahydrofuran and acetone, and dried under reduced pressure with a vacuum drier. After the drying was completed, the P value of the elution peak of the liquid crystal molecules was measured by the same evaluation method as in Example 1 using the obtained liquid crystal display element spacer as a stationary phase. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 4 (Preparation of fine particles) The same method as in Example 3 was used. (Surface Treatment of Fine Particles) A spacer for a liquid crystal display element was obtained in the same manner as in Example 3 except that cetyl methacrylate was used instead of lauryl methacrylate. Using the obtained spacer for a liquid crystal display element as a stationary phase, the P value of the elution peak of liquid crystal molecules was measured by the same evaluation method as in Example 1. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 5 (Preparation of fine particles) 3% aqueous solution of polyvinyl alcohol 8
A mixture of 70 parts by weight of divinylbenzene, 30 parts by weight of dipentaerythritol hexaacrylate, 15 parts by weight of acrylonitrile, and 3 parts by weight of benzoyl peroxide was added to 00 parts by weight, and the mixture was stirred with a homogenizer to adjust the particle size. Thereafter, the temperature was raised to 80 ° C. by a stream of nitrogen while 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 resulting fine particles had an average particle size of 6.0 μm, a CV value of 3%, and a 10% K value of 5000 N / mm ² .

(Surface Treatment of Fine Particles) The fine particles were subjected to a surface treatment in the same manner as in Example 1. Using the obtained spacer for a liquid crystal display element as a stationary phase, the P value of the elution peak of liquid crystal molecules was measured by the same evaluation method as in Example 1. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 The P value of the elution peak of liquid crystal molecules was measured by the same evaluation method as in Example 1 except that the fine particles obtained in Example 1 were used as a stationary phase without surface treatment. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. Table 1 shows the results
It was shown to.

Comparative Example 2 (Preparation of fine particles) The same procedure as in Example 1 was carried out. (Surface treatment of fine particles) In a separable flask, 10 parts by weight of the fine particles prepared by the above operation, 100 parts by weight of hexane,
Add 1 part by weight of tridecyltriethoxysilane,
For 1 hour with stirring. After completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration through a membrane filter having a pore size of 3 μm. The obtained fine particles were dried under reduced pressure at 140 ° C. for 1 hour using a vacuum dryer. After the drying is completed, the obtained liquid crystal display element spacer is used as a stationary phase and the P of the elution peak of the liquid crystal molecule is determined in the same manner as in Example 1.
The value was measured. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 In 800 parts by weight of a 3% aqueous solution of polyvinyl alcohol, 30 parts by weight of divinylbenzene, 50 parts by weight of tetramethylolmethanetetraacrylate, and cetyl methacrylate 2
0 parts by weight, a mixture of 3 parts by weight of benzoyl peroxide was added,
The particle size was adjusted by stirring with a homogenizer. Thereafter, the temperature was raised to 80 ° C. by nitrogen gas stream while stirring,
The reaction was performed for 15 hours. After completion of the reaction, the reaction solution was taken out, and the particles and the reaction solution were separated by filtration through a membrane filter having a pore size of 3 μm. After the obtained fine particles were washed with hot ion-exchanged water and methanol, a classification operation was performed. These fine particles had an average particle size of 5.0 μm, a CV value of 3%, and a K value of 42%.
00 N / mm ² .

Using the obtained spacer for a liquid crystal display element as a stationary phase, the P value of the elution peak of liquid crystal molecules was measured by the same evaluation method as in Example 1. Further, a liquid crystal display element was manufactured using the above-described spacer for a liquid crystal display element, and the abnormal liquid crystal orientation was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0068]

[Table 1]

From Table 1, it can be seen that the liquid crystal display device using the spacer for a liquid crystal display device obtained in Examples 1 to 5, in which the P value of the elution peak of the liquid crystal molecule is 25 or more, has an increased abnormal orientation even when subjected to impact. No display quality was exhibited.
On the other hand, in the liquid crystal display devices using the liquid crystal display device spacers obtained in Comparative Examples 1 to 3, an increase in abnormal alignment after impact was observed.

Further, in order to compare the density of the hydrophobic portion between the liquid crystal display element spacer obtained in Comparative Example 3 and the liquid crystal display element spacer obtained in Example 4, the TOF-SI
When the surface amounts of both cetyl methacrylates were relatively compared using MS, Example 4 clearly showed a higher value.

[0071]

Since the liquid crystal display element spacer of the present invention has the above-described structure, it does not adversely affect the liquid crystal such as disturbing the alignment of the liquid crystal even when subjected to a strong shock, and has a high quality display performance. A display element can be obtained. Further, by using the spacer for a liquid crystal display element of the present invention, a liquid crystal display element having high-quality display performance can be obtained without adversely affecting the liquid crystal such as disturbing the alignment of the liquid crystal even when subjected to a strong shock.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a liquid crystal display device using a liquid crystal display device spacer of the present invention.

FIG. 2 is a schematic diagram of a liquid chromatography apparatus used in Examples.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Polarizing sheet 2 Transparent substrate 3 Insulating film 4 Transparent electrode 5 Alignment film 6 Liquid crystal 7 Liquid crystal display element spacer 8 Sealing material 10 Liquid crystal display element 20 Liquid chromatography 21 Mobile phase 22 Liquid feed pump 23 Autosampler 24 Spacer filled column 25 Ultraviolet Detector 26 Recorder

Claims (3)

[Claims] 1. A spacer for a liquid crystal display element used for a liquid crystal display element, wherein the spacer for a liquid crystal display element is filled in a column and used as a stationary phase, and a solubility parameter is 8.
In the elution peak shape obtained when liquid crystal molecules are flown into a system using a liquid of 5 to 23.5 (cal / cm ³ ) as a mobile phase, the retention time of the elution peak is t (min),
The peak width at 50% of the elution peak height is W _1/2
(Min), the column length used for the measurement is L (mm), and the average particle size of the liquid crystal display element spacer filled in the column is D
A parameter (P value) represented by the following formula (1) is 25 or more when (mm), and is a spacer for a liquid crystal display element. P value = (t / W _1/2 ) ² × D / L (1) 2. The spacer for a liquid crystal display device according to claim 1, wherein the spacer has a long-chain alkyl group having 4 to 22 carbon atoms on the surface. 3. A liquid crystal display device comprising the liquid crystal display device spacer according to claim 1.