JP2007233132A - Substrate with protrusion for alignment control and liquid crystal display device using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate for a liquid crystal display device with minute protrusions for alignment control having an exact cross-sectional shape and exact dimensions, and an MVA-LCD using the same. <P>SOLUTION: The protrusions for alignment control are formed by curing a negative photosensitive resin composition containing (A) a binder resin, (B) a photopolymerizable monomer, (C) a photopolymerization initiator and (D) a polymerization inhibitor, wherein the content of the polymerization inhibitor (D) in the negative photosensitive resin composition is confined to 0.001-0.3 wt.% when the total amount of the binder resin (A), the photopolymerizable monomer (B) and the photopolymerization initiator (C) is considered to be 100 wt.%. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vertically aligned (VA) type liquid crystal display (LCD), and more particularly, to an alignment control protrusion used in an alignment-divided vertical alignment (MVA, multi domain vertically aligned) type LCD. The present invention relates to a substrate having the same and a liquid crystal display device using the same.

  MVA-LCD (Multi-Domain Vertical Alignment-Liquid Crystal Display) is controlled so that the liquid crystal molecules are tilted in multiple directions within a single pixel. It is a vertical alignment type liquid crystal display device in which alignment control projections are provided on a substrate so as to perform gradation display, and is said to be a liquid crystal display device having excellent contrast, viewing angle characteristics, and response speed.

  FIGS. 1A and 1B are explanatory views schematically showing the operation of the MVA-LCD in its cross section. As shown in FIGS. 1A and 1B, a general MVA-LCD 10 is configured by sandwiching liquid crystal molecules 15 between two substrates 11 and 12. The substrate 11 is a substrate located on the back side when viewed from the screen observer, and is provided with a TFT (not shown) for driving a liquid crystal and an alignment control protrusion 13. The substrate 12 is a substrate positioned on the screen observer, and is provided with a color filter layer (not shown) for coloring display light transmitted through the liquid crystal 15 and an alignment control protrusion 14. The alignment control protrusions 13 and the alignment control protrusions 14 are alternately arranged.

  FIG. 1A shows a state when no voltage is applied. When no voltage is applied, the liquid crystal molecules 15 are vertically aligned between the two substrates, but in the vicinity of the alignment control protrusion 13 and the alignment control protrusion 14, The liquid crystal molecules 15 are slightly inclined due to the influence of the inclined surfaces of the protrusions 13 and 14. FIG. 1B shows a state when a voltage is applied. When a voltage is applied, the liquid crystal molecules 15 near the slopes of the protrusions 13 and 14 are tilted, and the liquid crystal molecules other than the tilted portions are sequentially aligned in the same orientation. It becomes like this. That is, by providing a protrusion in place of the rubbing treatment, the alignment of liquid crystal molecules when a voltage is applied can be controlled.

  The shape of the alignment control protrusion is not particularly limited as long as the liquid crystal molecules on the pixel are regularly divided into two or more, but the shape when viewed from the direction perpendicular to the substrate is a dot. It is preferable to have regularity such as a shape, a stripe shape, or a zigzag shape. Moreover, it is preferable that the cross-sectional shape when viewed from a direction horizontal to the substrate is a semicircular shape, a semi-elliptical shape, or a polygonal shape such as a triangle. In particular, it is essential that the side surface has a forward taper as shown in FIG. In the case of non-taper (b) or reverse taper (c), not only the tilt direction of liquid crystal molecules cannot be controlled, but also display unevenness due to disturbance or reduction in luminance is caused, so the cross-sectional shape is very important. Element.

  Conventionally, such alignment control protrusions are formed by a photolithography method using a positive photosensitive resin composition containing a novolac resin as a main component. That is, a positive photosensitive resin composition is applied onto a substrate, dried to form a film, and then partially exposed and developed through a photomask to form the protrusions. It is common to carry out heat curing (post-bake) after development (see Patent Document 1 and Non-Patent Document 1).

  However, in recent years, as the resolution of MVA-LCD has been increased, the alignment control protrusions have also been required to have higher definition. For example, when a 2.4-inch mobile phone with a conventional resolution of QVGA (320 × 240 pixels) has a resolution of VGA (640 × 480 pixels), the width of one pixel is about 75 μm to about It will be as narrow as 25 μm. Therefore, the alignment control projection pattern formed in a pixel having a width of 25 μm needs to be smaller. Furthermore, with the diversification of products, the sizes (height and line width) required for the alignment control protrusions and the tapered shape of the side surface are various, and it is required to flexibly cope with these.

  However, when a novolac-type positive photosensitive resin composition is used as a material for forming the alignment control protrusion, it is difficult to form the fine pattern as described above. That is, the novolac resin has a very large heat flow in the post-bake process, and this causes the projection pattern to spread in the horizontal direction, so that a fine pattern cannot be formed. Further, common defects derived from fine defects of the mask are likely to occur, and the yield is adversely affected, so that there is a problem in cost and process.

  On the other hand, a method of forming alignment control protrusions by applying a negative photosensitive resin composition and a photolithography method is also known (see Patent Document 2). When forming alignment control protrusions by this method, alignment control protrusions that are larger than the photomask pattern were easily formed. For this reason, in order to make the pattern of the alignment control protrusion fine, the dimension of the mask pattern must be made smaller than this. For this reason, there is a problem that mask design becomes difficult and fine alignment control protrusions cannot be formed.

By reducing the exposure amount and the sensitivity of the negative photosensitive resin composition to reduce the degree of curing thereof, the size of the formed alignment control protrusion can be made closer to the mask pattern. For example, the sensitivity of the negative photosensitive resin composition is reduced by reducing the amount of initiator or monomer or using a monomer having a small number of functional groups. In this case, although the resolution is improved and the size of the alignment control protrusion approaches the size of the mask pattern, there is a problem that the cross-sectional shape and dimensions of the alignment control protrusion are likely to vary. Further, in such a method, since there are many parameters to be controlled, it is disadvantageous in terms of time and cost to cope with diversifying sizes and tapered shapes.
Japanese Patent No. 2947350 Japanese Patent Application Laid-Open No. 11-2487213 Electronic Journal October 1997 P.I. 33

  The present invention has been made to solve the above-mentioned problems, and includes a substrate for a liquid crystal display device having a fine alignment control protrusion and a protrusion having an accurate cross-sectional shape and dimensions. An object of the present invention is to provide an MVA-LCD using this.

That is, the invention according to claim 1 is a substrate with an alignment control protrusion having a protrusion for controlling the alignment direction of the liquid crystal while constituting a liquid crystal display device by sandwiching a liquid crystal with an opposing substrate.
The alignment control protrusion is formed by curing a negative photosensitive resin composition containing (A) a binder resin, (B) a photopolymerizable monomer, (C) a photopolymerization initiator, and (D) a polymerization inhibitor. Has been
And the content of (D) polymerization inhibitor in the said negative photosensitive resin composition is the sum total of three of (A) binder resin, (B) photopolymerizable monomer, and (C) photoinitiator. A substrate with protrusions for orientation control, characterized by being in the range of 0.001 to 0.3% by weight when it is 100% by weight.

  The invention according to claim 2 is the substrate with alignment control protrusions according to claim 1, wherein the polymerization inhibitor (D) contains a hydroquinone polymerization inhibitor.

  The invention according to claim 3 is the substrate with alignment control protrusions according to claim 1 or 2, wherein the binder resin (A) is a resin having alkali solubility.

  The invention according to claim 4 is the substrate with alignment control protrusions according to any one of claims 1 to 3, wherein the substrate includes a color filter layer that colors transmitted light.

  The invention according to claim 5 is a liquid crystal display device using the substrate with alignment control protrusions according to any one of claims 1 to 4.

  In the present invention, when the content of the (D) polymerization inhibitor is 100% by weight, the total of (A) the binder resin, (B) the photopolymerizable monomer, and (C) the photopolymerization initiator is 100% by weight. Since the negative control photosensitive resin composition in the range of 0.001 to 0.3% by weight is used to form the alignment control protrusions, as can be seen from the examples described later, excellent resolution and An alignment control protrusion having shape stability can be formed. Therefore, an MVA-LCD having no display unevenness and high definition and a high viewing angle can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail.

[Production of substrate with protrusions for orientation control]
As an example of the alignment control projection substrate, a description will be given below of an example in which a color filter layer is provided on a transparent substrate and the alignment control projection is formed thereon. However, the present invention does not necessarily require a color filter layer and is not limited to the following description.

  As an example of the substrate with alignment control protrusions of the present invention, a color filter layer, a transparent conductive film layer, and an alignment control protrusion provided in this order on a transparent substrate, or a color filter layer and a transparent conductive film The structure which provided the layer, the processus | protrusion for orientation control, the alignment film layer in this order, or the laminated body structure which provided the transparent protective film layer between arbitrary layers as needed can be mentioned. The color filter layer includes a black matrix for improving contrast and a colored pixel layer for coloring transmitted light. The colored pixel layers have red, green, and blue colors, respectively. The alignment control projection substrate is opposed to a counter substrate on which an electrode such as a thin film transistor is formed to constitute an LCD through a liquid crystal layer.

  The substrate having transparency is preferably a plate-like substrate, and examples thereof include glass or a plastic sheet or film such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyethersulfone or polyacrylate. Further, since post-baking is performed after forming the alignment control protrusions, a glass substrate excellent in heat resistance is preferable, and furthermore, a glass having a low coefficient of thermal expansion and excellent dimensional stability in the heating process should be selected. Is preferred.

The black matrix constituting the color filter layer can be formed using a known method. For example, a thin film of a metal or metal oxide such as chromium or titanium is formed on a substrate by a method such as sputtering, and then patterned by a technique such as etching. Alternatively, light-shielding fine particles such as carbon black and metal oxides and colorants such as pigments or dyes are mixed in the photosensitive resin composition, and this is formed as a photosensitive resin layer on the substrate to perform photolithography. Formed by law. Alternatively, when forming a colored pixel layer composed of red, green, blue, etc., which will be described later, these layers may be formed by laminating layers of these colors, etc. Also good.

  The colored pixel layer is provided in the opening of the black matrix, and a pixel pattern composed of three primary colors, usually a red pixel pattern, a green pixel pattern, and a blue pixel pattern, is arranged in a desired shape. As the formation method, there are already known methods such as a pigment dispersion method, a dye method, an electrodeposition method, a printing method, a transfer method and a method of forming each pixel by ink jetting. In the present invention, any method is used. Also good.

Next, a transparent conductive film layer is provided on the substrate on which the color filter layer is formed. The transparent conductive film layer is provided to control the behavior of the liquid crystal sandwiched between the substrates by transmitting an electric signal, and the transparent conductive film layer is provided on at least one of the opposing liquid crystal display device substrates. It is essential. Normally, the transparent conductive film layer is formed immediately below the alignment control protrusion, but it can also be provided on the alignment control protrusion by vapor deposition or the like. The transparent conductive film layer is made of a material that is transparent, conductive, and can be formed into a thin film. Usually, an ITO (indium and tin composite oxide) film is used, and the other is IZO (indium and zinc composite oxide). And SnO ₂ (tin dioxide) film are selected and formed by a method such as sputtering or vacuum deposition.

  Subsequently, alignment control protrusions are formed. On the substrate, the negative photosensitive resin composition of the present invention is applied to a bar coater, applicator, wire bar, spin coater, roll coater, slit coater, curtain coater, die coater, comma coater, or other known coating methods. Laminate using. The negative photosensitive resin composition may be diluted with a solvent, prepared as a photosensitive solution, and coated on the substrate by the above method. In this case, the solvent needs to be removed after coating on the substrate. is there. Thereafter, pattern exposure is performed by irradiating light through a photomask having a predetermined pattern, then developing with an alkali developer, and unexposed portions are dissolved and removed to form alignment control protrusions. it can.

  Examples of the pattern exposure include an ultra-high pressure mercury lamp, a high-pressure mercury lamp, a medium-pressure mercury lamp, a low-pressure mercury lamp, a xenon lamp, and a halogen lamp, but are not limited thereto and can be performed by other known methods.

  The alignment control protrusions in the present invention are post-baked after the photolithography process, thereby promoting the curing of the alignment control protrusions and improving the adhesion to the substrate, and further imparting solvent resistance and chemical resistance. In addition, the shape can be made smooth by appropriate heat shrinkage and heat flow, and the orientation of liquid crystal molecules can be further improved.

  Next, an alignment film layer is provided on the substrate as necessary. The alignment film layer is provided for vertically aligning the liquid crystal compound. A transparent and insulating material is used for the alignment film layer, and generally a polyimide resin or the like is used. The alignment film layer is formed by forming a polyimide resin solution, a polyamic acid solution, or the like by a known coating method or printing method, and then baking.

The transparent protective film layer has a function of flattening a step generated when the black matrix and the colored pixel layer are formed. As a material for forming the transparent protective film layer, photocurable, thermosetting, light and thermosetting resin compositions, resin cured products such as epoxy, acrylic and polyimide, or inorganic compounds by sputtering or vapor deposition, etc. Any material can be used as long as the object can be achieved. In consideration of the surface state of the color filter layer, it can be formed in the range of 0.5 to 3 μm.

In addition, the alignment control protrusion of the present invention is not limited to the case of using this layer structure, and the alignment control protrusion can be formed in any layer as required.
[Negative photosensitive resin composition]
The negative photosensitive resin composition of the present invention comprises (A) a binder resin, (B) a photopolymerizable monomer, (C) a photopolymerization initiator, (D) a polymerization inhibitor and a solvent.

  It is preferable that (A) binder resin of the negative photosensitive resin composition in this invention has alkali solubility. In this case, the negative photosensitive resin composition can be developed with an alkaline aqueous solution and can be used in a conventional process, which is advantageous in terms of cost and is preferable from the viewpoint of the environment. Moreover, a resin having radical crosslinkability is preferable from the viewpoint of sensitivity, development stability, solvent resistance, and the like, and a resin having an aromatic ring is preferable from the viewpoint of electrical characteristics. Such a resin is not particularly limited, and examples thereof include resins having phenolic hydroxyl groups, epoxy resins, and modified products thereof.

  Examples of the resin having a phenolic hydroxyl group include a cresol novolac resin, polyvinylphenol, and a copolymer of p-vinylphenol and styrene. Polyvinylphenol can be obtained by polymerizing hydroxystyrenes having a substituent group or hydroxystyrenes having no substituent group alone or two or more thereof in the presence of a radical polymerization initiator or a cationic polymerization initiator. . Examples of the hydroxystyrenes having a substituent include 2- (p-hydroxyphenyl) propylene. Moreover, p-hydroxystyrene can be illustrated as hydroxystyrenes without a substituent.

  The epoxy resin can be used without any limitation as long as it has alkali developability, and among them, an unsaturated monobasic acid and a phenol compound are added to the polyfunctional epoxy resin, Those crosslinked with an acid anhydride are particularly preferred. These resins may be used in combination of two or more in consideration of developability, sensitivity, thermoplasticity and the like.

  The weight average molecular weight Mw of the binder resin of the present invention is preferably in the range of 2000 to 40000, more preferably in the range of 2000 to 15000, from the viewpoint of strength and developability. In addition, Mw is the weight average molecular weight of polystyrene conversion measured by GPC method.

  Examples of the photopolymerizable monomer (B) in the present invention include a monomer having a vinyl group or an allyl group, an oligomer, and a polymer having a vinyl group or an allyl group at the terminal or side chain. Such compounds include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, cyclohexyl (meth) acrylate, polyethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol. Various acrylic esters and methacrylic esters such as hexa (meth) acrylate, tricyclodecanyl (meth) acrylate, melamine (meth) acrylate, epoxy (meth) acrylate, (meth) acrylic acid, styrene, vinyl acetate, (meta ) Acrylamide, N-hydroxymethyl (meth) acrylamide, acrylonitrile, urethane acrylate, polyfunctional (meth) acrylate having urethane group polyester, etc. Kill, but not limited thereto. Moreover, you may use these in mixture of 2 or more types as needed.

The amount of these (B) photopolymerizable monomers can be in the range of 20 to 300% by weight, preferably 30 to 120% by weight, based on the (A) binder resin. If it is 20% by weight or less, the sensitivity is lowered, and if it is 300% by weight or more, the tackiness of the coating film is too large, causing mask contamination at the time of exposure, and the electrical characteristics of the alignment control protrusions formed are also poor. Become.

  The photopolymerization initiator (C) used in the present invention includes benzophenone, 4,4′-bis (dimethylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, 2-ethylanthraquinone, phenanthra. Quinone, benzyldimethyl ketal, benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, ethyl benzoin, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane-1- ON, Lophine dimers such as 2- (o-chlorophenyl) -4,5-diphenylimidazolyl dimer, N-aryl glycines such as N-phenylglycine, organic azides such as 4,4′-diazidochalcone Kind, 3, ', And organic peroxides such as 4,4'-tetra (tert- butylperoxy carboxyl) benzophenone.

  The above (C) photopolymerization initiator is used alone or in combination of two or more. As the sensitizer, for example, α-acyloxime ester, acylphosphine oxide, methylphenylglyoxylate, benzyl, 9,10- Compounds such as phenanthrenequinone, camphorquinone, ethylanthraquinone, 4,4'-diethylisophthalophenone, 4,4'-diethylaminobenzophenone, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 3-mercaptopropionic acid are also used in combination. be able to.

  The amount of these (C) photopolymerization initiators is preferably 0.1 to 30% by weight, more preferably 3 to 20% by weight, based on (A) the binder resin.

  As the polymerization inhibitor (D) of the present invention, hydroquinone, such as hydroquinone and methoquinone can be used, but pyrogallol, tert-butylcatechol, cuprous chloride, 2,6-di-tert. A combination with -butyl-p-cresol is also possible.

  (D) The amount of the polymerization inhibitor is 0.001 to 1 when the total of (A) binder resin, (B) photopolymerizable monomer, and (C) photopolymerization initiator is 100% by weight. 0.3 weight% is preferable, More preferably, it is 0.005-0.1 weight%. If it is 0.001% by weight or less, the effect of adding a polymerization inhibitor is insufficient, and if it exceeds 0.3% by weight, the sensitivity is lowered or the adhesion is lowered, or the cross-sectional shape approaches from a forward taper to a non-taper. This makes it impossible to control the orientation of the liquid crystal.

  In addition to the above-mentioned components, the negative photosensitive resin composition of the present invention is compatible with additives as necessary, such as for improving applicability, adhesion, heat resistance, and chemical resistance, such as a plasticizer. Stabilizers, surfactants, colorants, leveling agents, coupling agents, fillers, and the like can be added as long as the object or effect of the present invention is not impaired.

Solvents used to make a negative photosensitive resin as a sensitizing solution include dichloroethane, chloroform, acetone, 2-butanone, cyclohexanone, ethyl acetate, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, 2-ethylethoxy. Acetate, 2-butoxyethyl acetate, 2-methoxyethyl ether, 2-ethoxyethyl ether, 2- (2-ethoxyethoxy) ethanol, 2- (2-butoxyethoxy) ethanol, 2- (2-ethoxyethoxy) ethyl acetate 2- (2-butoxyethoxy) ethyl acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, tetrahydrofuran, 1,4-dioxy Emissions, and the like.

  Hereinafter, although an example is given and explained about an embodiment of the invention, the present invention is not limited to an example mentioned below. Further, since the negative photosensitive resin composition used in the present invention is extremely sensitive to light, it is necessary to prevent exposure to unnecessary light such as natural light, and all operations are performed under a yellow or red lamp. It goes without saying that it will be done.

[Example 1]
A Cr thin film was formed on a transparent substrate by sputtering, and a black matrix was formed by a photoetching method. On this, a red photosensitive resin composition is applied, exposed, developed, and post-baked to form a red pixel pattern, and then the same processing is performed on the green photosensitive resin composition and the blue photosensitive resin composition. A green pixel pattern and a blue pixel pattern were formed. Next, an ITO film was formed on the entire surface by sputtering to form a transparent conductive film layer.

  Next, a negative photosensitive resin composition having the following composition was prepared.

Binder resin ("Maruka Linker M" manufactured by Maruzen Petrochemical Co., Ltd.)
20g
16 g of photopolymerizable monomer ("Aronix M-402" manufactured by Toa Gosei Co., Ltd.)
Photoinitiator (Ciba Specialty Chemicals “IrgOXE01”) 3.5g
Polymerization inhibitor hydroquinone (manufactured by Kanto Chemical Co., Inc.) 0.004 g
Cyclohexanone (manufactured by Kanto Chemical)
110g
This negative photosensitive resin composition was applied to the substrate with a spin coater to form a coating film of the photosensitive resin composition having a thickness of 1.9 μm. After pre-baking, light of an ultrahigh-pressure mercury lamp was irradiated through a photomask having an octagonal opening pattern with a diameter of 8 μm, followed by alkali development to form a dot pattern. Subsequently, post-baking was performed at 230 ° C. for 30 minutes to obtain a substrate with alignment control protrusions. The exposure amount was 150 mJ / cm ² .

  Table 1 shows the evaluation results of the dimensions (lower bottom line width), cross-sectional shape, and pattern stability of the obtained alignment control protrusions. The dimensional evaluation was performed using an optical microscope. The cross-sectional shape was evaluated using a scanning electron microscope (SEM). The evaluation rank was ◯: a forward tapered shape, or a non-tapered shape and a reverse tapered shape. Concerning shape stability, at least 1 out of 5 measurement points, the above dimensions are shifted from the average value by 0.3 μm or more, or the cross-sectional shape is x, otherwise, Was marked as ○. In Table 1, the polymerization inhibitor weight% is the weight of (D) polymerization inhibitor divided by the total weight of (A) binder resin, (B) photopolymerizable monomer, and (C) photopolymerization initiator. Represents a thing.

[Example 2]
A negative photosensitive resin composition was prepared in the same manner as in Example 1 except that the amount of 0.004 g of polymerization inhibitor hydroquinone (manufactured by Kanto Chemical Co., Inc.) was increased to 0.015 g. A color filter substrate having was obtained. Table 1 shows the evaluation results of the obtained alignment control protrusions.

[Example 3]
A negative photosensitive resin composition was prepared in the same manner as in Example 2 except that 0.006 g of methoquinone was used instead of 0.004 g of the polymerization inhibitor hydroquinone (manufactured by Kanto Chemical Co., Inc.), and this was used for orientation. A color filter substrate having control protrusions was obtained. Table 1 shows the evaluation results of the obtained alignment control protrusions.

[Comparative Example 1]
Except for the polymerization inhibitor hydroquinone (manufactured by Kanto Chemical Co., Inc.), a negative photosensitive resin composition was prepared in the same manner as in Example 1, and a color filter substrate having alignment control protrusions was obtained using this. . Table 1 shows the evaluation results of the obtained alignment control protrusions.

[Comparative Example 2]
A negative photosensitive resin composition was prepared in the same manner as in Example 1 except that the amount of the polymerization inhibitor hydroquinone (manufactured by Kanto Chemical Co., Inc.) was increased to 0.15 g, and this was used to form alignment control protrusions. However, a large amount of peeling occurred, and it was not possible to obtain a color filter substrate of a level that can be evaluated. The exposure amount was 250 mJ / cm ² and sufficient exposure was performed.

[Comparative Example 3]
Photopolymerization initiator (Ciba Specialty Chemicals “IrgOXE01”) 3.5 g was reduced to 1.5 g, and the polymerization inhibitor hydroquinone (Kanto Chemical Co., Ltd.) was removed. Then, a negative photosensitive resin composition was prepared, and an exposure amount was 250 mJ / cm ² using this to obtain a color filter substrate having alignment control protrusions. Table 1 shows the evaluation results of the obtained alignment control protrusions.

表１に示すように、重合禁止剤としてハイドロキノンあるいはメトキノンを適正量添加して得られるネガ型感光性樹脂組成物を調整し、これを用いて配向制御用突起を形成した実施例１〜３では、マスク開口に対して＋３μm以下で断面形状およびパターン安定性も良好な配向制御用突起を形成することができた。さらに、安定性を悪化させることなく、適正量の重合禁止剤によって寸法の調整が可能であることから、多様な要求スペックにも容易に対応可能であることも確認できた。

As shown in Table 1, in Examples 1 to 3 in which a negative photosensitive resin composition obtained by adding an appropriate amount of hydroquinone or methoquinone as a polymerization inhibitor was prepared, and alignment control protrusions were formed using this. Further, alignment control protrusions having a cross-sectional shape and a good pattern stability of +3 μm or less with respect to the mask opening could be formed. Furthermore, since it is possible to adjust the dimensions with an appropriate amount of polymerization inhibitor without deteriorating the stability, it was also confirmed that various required specifications can be easily accommodated.

  On the other hand, in Comparative Example 1 in which no hydroquinone polymerization inhibitor was added, the size of the alignment control protrusion (12.1 μm) was larger than that of the mask pattern (8 μm), and a fine pattern was formed. I couldn't. Further, in Comparative Example 2 in which the polymerization inhibitor was more than the appropriate amount, the adhesion was remarkably lowered, and the remaining pattern was reverse tapered. Further, in Comparative Example 3 in which the amount of the initiator was reduced, the characteristics of the dimensions and the cross-sectional shape were good, but the sensitivity was lowered and the shape stability was deteriorated, and the alignment control projection having good characteristics was not obtained.

An MVA-LCD was produced using the color filter substrate having the alignment control protrusions obtained in Examples 1 to 3. As a result, this MVA-LCD was excellent in display performance with high definition, high viewing angle and no display unevenness. Was shown.
The present invention provides a substrate for a liquid crystal display device having a liquid crystal alignment control projection having excellent resolution, cross-sectional shape, and shape stability, and further, by using this substrate, display unevenness with high definition and high viewing angle. It is possible to provide an MVA-LCD that exhibits excellent display characteristics without any problems.

Explanatory drawing which shows the liquid crystal display device using the board | substrate with the protrusion for orientation control. Plane explanatory drawing which shows the shape of the protrusion for orientation control.

Explanation of symbols

10 ... MVA-LCD
DESCRIPTION OF SYMBOLS 11 ... Back side substrate 12 ... Observer side substrate 13 ... Orientation control protrusion 14 ... Orientation control protrusion 15 ... Liquid crystal molecule

Claims (5)

In a substrate with an alignment control protrusion having a protrusion for controlling the alignment direction of the liquid crystal while constituting a liquid crystal display device by sandwiching a liquid crystal with an opposing substrate,
The alignment control protrusion is formed by curing a negative photosensitive resin composition containing (A) a binder resin, (B) a photopolymerizable monomer, (C) a photopolymerization initiator, and (D) a polymerization inhibitor. Has been
And the content of (D) polymerization inhibitor in the said negative photosensitive resin composition is the sum total of three of (A) binder resin, (B) photopolymerizable monomer, and (C) photoinitiator. A substrate with protrusions for orientation control, characterized by being in the range of 0.001 to 0.3% by weight when it is 100% by weight.   2. The substrate with alignment control protrusions according to claim 1, wherein the polymerization inhibitor (D) contains a hydroquinone polymerization inhibitor.   The substrate with alignment control protrusions according to claim 1, wherein the (A) binder resin is an alkali-soluble resin.   The said board | substrate is provided with the color filter layer which colors the transmitted light, The board | substrate with an orientation control protrusion in any one of Claims 1-3 characterized by the above-mentioned.   A liquid crystal display device using the substrate with alignment control protrusions according to claim 1.

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