KR100969330B1 - Alignment agent of liquid crystal, alignment film of liquid crystal including the same, and liquid crystal display including the same - Google Patents

Abstract

The present invention includes a polysiloxane polymer prepared by polymerizing any one first alkoxy silane compound selected from the group consisting of compounds represented by the following Chemical Formulas 1 to 3 and a second alkoxy silane compound represented by the following Chemical Formula 4, and a solvent: It provides a liquid crystal photo-alignment agent.

[Formula 1]

Si (R ₁ ) ₄

(2)

Si (R ₂ ) ₄

(3)

(R ₄ ) ₃ Si- (R ₃ ) _n -Si (R ₄ ) ₃

[Chemical Formula 4]

Si (R ₅ ) ₄

The definitions for R ₁ to R ₅ are as described in the detailed description of the specification. The liquid crystal photoalignment agent has excellent liquid crystal photoalignment and vertical alignment force due to polarized ultraviolet light, has a long lifetime, stable pretilt angle retention, improved afterimage characteristics, and excellent liquid crystal photoalignment and chemical resistance. The display quality of (LCD) can be improved, and it is suitable for use as a liquid crystal photoalignment agent for LCD TVs. In addition, the liquid crystal photoalignment agent is easily stripped by a rework solvent due to poor printing.

Photo alignment, liquid crystal alignment, liquid crystal alignment agent, polysiloxane, pretilt angle, voltage holding ratio, liquid crystal photo alignment, alignment stability

Description

Liquid crystal photo-alignment agent, a liquid crystal photo-alignment film comprising the same, and a liquid crystal display device comprising the same ALIGNMENT AGENT OF LIQUID CRYSTAL, ALIGNMENT FILM OF LIQUID CRYSTAL INCLUDING THE SAME

The present invention relates to a liquid crystal photoalignment agent used in a liquid crystal display device, a liquid crystal photoalignment film including the same, and a liquid crystal display device including the same. More particularly, the liquid crystal photoalignment and vertical alignment force due to polarized ultraviolet rays are excellent. Long lifespan, stable pretilt angle maintenance, improved afterimage property, excellent liquid crystal photo-alignment and chemical resistance, and easy liquid stripping by rework solvent due to poor printing An optical alignment agent, a liquid crystal photoalignment film including the same, and a liquid crystal display including the same.

In the current liquid crystal device (LCD), a liquid crystal photo-alignment agent is generally applied to a glass substrate on which a transparent indium-tin oxide (ITO) conductive film is deposited, and then cured with heat to form an alignment layer. Two substrates are bonded to each other in opposition to inject a liquid crystal, or a liquid crystal is dropped into one of the substrates, and then the opposing substrates are bonded to each other. The liquid crystal dropping method is adopted in the 5th generation or larger line.

The liquid crystal photoalignment agent generally used is a solution in which a polymer resin which forms an alignment film after application is dissolved in a solvent. The polymer resin used here is a polyamic acid obtained by condensation of an aromatic acid dianhydride and an aromatic diamine or imidization by dehydrating and ring-closing it. Polyimide is used.

However, when only aromatic acid dianhydrides and aromatic diamines are used as described above, the thermal stability, chemical resistance, mechanical properties, and the like are excellent, but transparency and solubility are degraded by charge transfer complexes, and electro-optic properties are degraded. There is a problem. In order to solve this problem, there has been an attempt to improve the problem by introducing an aliphatic cyclic acid dianhydride monomer or an aliphatic cyclic diamine (Japanese Patent Laid-Open No. 11-84391). In addition, functional diamines having side chains or functional acid dianhydrides having side chains and the like have been introduced for increasing the line diameter square and stability of liquid crystals (Japanese Patent Laid-Open No. 06-136122).

In addition, the development of a vertical alignment layer that can be applied in a vertical alignment mode (VA mode) constituting the LCD panel by aligning the liquid crystal perpendicular to the surface (US Patent No. 5,420,233). The vertical alignment mode has a large viewing angle and does not require an orientation process such as rubbing, so that it is easy to be enlarged. In the case of large display devices larger than 40 inches, many panel makers adopt the vertical alignment mode.

However, as the vertical alignment type liquid crystal display device is enlarged, various problems are difficult to solve with the conventional liquid crystal photoalignment agent. In particular, in the case of the polyamic acid aligning agent is subjected to the printing step and curing step of about 200 ℃ in the LCD manufacturing process, the imidation ratio is about 20 to 70%, so that there is a large amount of carboxyl groups that are not imidized due to the imidization surface. These uncured carboxyl groups are known to adsorb with the ionic impurities in the liquid crystal, thereby lowering the voltage holding ratio and promoting afterimage generation.

In the case of the polyimide aligning agent, since it is impossible to achieve 100% imidization, there is a material problem in which afterimages develop in long-term driving. In addition, functional diamine compounds having side chain groups are introduced into the polymer main chain in order to realize vertical alignment. In this case, hydrophobic side chains lower the surface tension of the alignment layer to express high diameter squares of 80 to 89 °. . However, long-chain alkyl groups having 6 to 24 carbon atoms, which are used as side chains of functional diamines, have a problem in that staining occurs on the screen due to a decrease in line diameter squares when subjected to physical shocks such as liquid crystal dropping.

Therefore, research on inorganic alignment films has been continued for a long time in order to overcome the limitations of the organic polyimide alignment films. Inorganic alignment films have a large strength as next-generation alignment films because they have less change in physical properties of the organic alignment films and do not oxidize or generate ionic impurities even at high temperatures, resulting in fewer display problems such as afterimages and stains during long-term operation.

The inorganic alignment film may be formed using an inorganic deposition method in which an inorganic film is formed on an LCD substrate using a method such as chemical vapor deposition (CVD) of silicon oxide or silane monomer.

Alternatively, the tetraalkoxy silane monomer is subjected to hydrocondensation polymerization to obtain polysiloxane resin, which is dissolved in a suitable solvent to form an alignment solvent similar to an existing organic alignment layer, which is then coated on a substrate and cured at a temperature of 80 to 400 ° C. There is a wet method of forming a film (Korean Patent Publication No. 1997-0062769).

The inorganic deposition method has a disadvantage in that deposition time is long, process cost is high, and application becomes difficult as the substrate size increases. On the other hand, the wet method can be said to be the best method for commercialization in that it can be applied to the same process as the existing polyimide alignment film as it is.

Particularly, Korean Laid-Open Publication No. 1997-0062769 does not use hydrolysis and condensation polymerization methods using water and an acid catalyst generally known in the process of polymerizing polysiloxane, and uses no water using oxalic acid and ethanol solution. Suggest. For example, if water is present, such as terraalkoxysilane, the polymerization proceeds vigorously to form gels or precipitates, and polymerization in oxalic acid and ethanol solution enables stable polymerization without precipitation or gels, and facilitates molecular weight control. Done.

However, in the case of forming a film by polymerizing a silane compound with the composition mentioned in Korean Patent Publication No. 1997-0062769 and forming a film by coating and curing the electrode on the electrode substrate, the film is not dissolved in the stripper solvent and the film damage due to foreign matters The disadvantage is that rework is not possible when it occurs.

In addition, Korean Laid-Open Publication No. 1997-0062769 proposes to use 5 to 43 mol% of a trialkoxy silane compound having a long chain alkyl group with respect to 1 mol of the tetraalkoxysilane compound. However, the silane compound having a long chain alkyl group is usually introduced to increase the pretilt angle of the liquid crystal. Unlike the organic alignment layer such as polyimide, the silicon alignment layer does not increase the diameter of the square due to the introduction of many long chain alkyl groups. In addition, when the long chain alkyl group is used in an amount of 5 mol% or more, the crosslinking rate is lowered during curing and voids are generated during film formation, which hinders the control of the liquid crystal and may cause residual images as impurities are eluted through the voids.

In addition, Korean Laid-Open Patent Publication No. 2006-0043402 is a conventional technology in which photo-alignment is imparted by introducing a photoreaction functional group such as a chalcone group into a silicon-based alignment layer. However, the technology of the photo-alignment silicon alignment film is still unfamiliar, and the Korean Laid-Open Patent Publication No. 2006-0043402 also relates to the silicon alignment layer, and the synthesis examples related to the photo-alignment are very fragmentary and technically insufficient. .

An object of the present invention is excellent in liquid crystal photo-alignment and vertical alignment force by polarized ultraviolet light, long life, stable pretilt angle maintenance, improved after-image characteristics, excellent liquid crystal photo-alignment and chemical resistance, printing failure It is to provide a liquid crystal photo-alignment agent that can be easily removed by the solvent during the rework due to.

Another object of the present invention is to provide a liquid crystal photoalignment film comprising the liquid crystal photoalignment agent.

Still another object of the present invention is to provide a liquid crystal display device including the liquid crystal photoalignment film.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by the average person from the following description.

According to an embodiment of the present invention, a polysiloxane prepared by polymerizing any one alkoxy silane compound selected from the group consisting of compounds represented by the following Chemical Formulas 1 to 3 and a second alkoxy silane compound represented by the following Chemical Formula 4 A liquid crystal photoalignment agent comprising a polymer and a solvent is provided.

[Formula 1]

Si (R ₁ ) ₄

(In the formula 1,

The four R ₁ are each independently a substituent selected from the group consisting of a hydroxy, an alkoxy group having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms)

[Formula 2]

Si (R ₂ ) ₄

(In Formula 2,

The four R _{2 's} each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, hydroxy, an alkoxy group having 1 to 5 carbon atoms, and 6 to 12 carbon atoms. Is any one substituent selected from the group consisting of aryloxy groups,

One or _two of the four R ₂ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, and 2 or 3 are hydroxy Oxy, alkoxy having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms).

(3)

(R ₄ ) ₃ Si- (R ₃ ) _n -Si (R ₄ ) ₃

(In Chemical Formula 3,

R ₃ is any one selected from the group consisting of an alkylene group or a fluoroalkylene group having 1 to 8 carbon atoms, an arylene group or a fluorarylene group having 6 to 20 carbon atoms, and n is an integer of 0 to 8,

Each of R ₆ is independently a substituent selected from the group consisting of hydroxy, alkoxy having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms)

[Formula 4]

Si (R ₅ ) ₄

(In Formula 4,

The four R ₅ are each independently a group consisting of a cumarine group, a chalcone group, a cinnamate group, a hydroxy group, an alkoxy group having 1 to 5 carbon atoms, and an aryloxy group having 6 to 20 carbon atoms. Any substituent selected from

One or two of the four R ₅ are each independently selected from the group consisting of a cumarine group, a chalcone group, and a cinnamate group, and two or three groups thereof are hydroxy and 1 to 3 carbon atoms. Alkoxy of 5 and an aryloxy group having 6 to 20 carbon atoms)

According to another embodiment of the present invention provides a liquid crystal photoalignment film prepared by applying the liquid crystal photoalignment agent to a substrate.

According to another embodiment of the present invention, a liquid crystal display including the liquid crystal photoalignment layer is provided.

Other specific details of embodiments of the present invention are included in the following detailed description.

The liquid crystal photo-alignment agent of the present invention is excellent in liquid crystal photo-alignment and vertical alignment force by polarized ultraviolet light, long life, stable pretilt angle maintenance, improved after-image characteristics, excellent liquid crystal photo-alignment and chemical resistance, etc. The display quality of a display device (LCD) can be improved and it is suitable for use as a liquid crystal photoalignment agent for LCD TVs. In addition, the liquid crystal photoalignment agent is easily stripped by a rework solvent due to poor printing.

Hereinafter, embodiments of the present invention will be described in detail. However, it should be understood that the present invention is not limited thereto, and the present invention is only defined by the scope of the following claims.

According to an embodiment of the present invention, a polysiloxane prepared by polymerizing any one alkoxy silane compound selected from the group consisting of compounds represented by the following Chemical Formulas 1 to 3 and a second alkoxy silane compound represented by the following Chemical Formula 4 A liquid crystal photoalignment agent comprising a polymer and a solvent is provided.

[Formula 1]

Si (R ₁ ) ₄

(In the formula 1,

The four R ₁ are each independently a substituent selected from the group consisting of a hydroxy, an alkoxy group having 1 to 5 carbon atoms, and an aryloxy group having 6 to 20 carbon atoms)

[Formula 2]

Si (R ₂ ) ₄

(In Formula 2,

The four R _{2 's} each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, hydroxy, an alkoxy group having 1 to 5 carbon atoms, and 6 to 12 carbon atoms. Is any one substituent selected from the group consisting of aryloxy groups,

One or _two of the four R ₂ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, and 2 or 3 are hydroxy Oxy, alkoxy having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms).

(3)

(R ₄ ) ₃ Si- (R ₃ ) _n -Si (R ₄ ) ₃

(In Chemical Formula 3,

R ₃ is any one selected from the group consisting of an alkylene group or a fluoroalkylene group having 1 to 8 carbon atoms, an arylene group or a fluorarylene group having 6 to 20 carbon atoms, and n is an integer of 0 to 8,

Each of the six R _{4 's} is independently a substituent selected from the group consisting of hydroxy, alkoxy having 1 to 5 carbon atoms, and aryloxy group having 6 to 20 carbon atoms)

[Formula 4]

Si (R ₅ ) ₄

(In Formula 4,

The four R ₅ are each independently a group consisting of a coumarin group, a chalcone group, a cinnamate group, a hydroxy group, an alkoxy group having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms. Any substituent selected from

One or two of the four R ₅ are each independently selected from the group consisting of a cumarine group, a chalcone group, and a cinnamate group, and two or three groups thereof are hydroxy and 1 to 3 carbon atoms. Alkoxy of 5 and an aryloxy group having 6 to 12 carbon atoms)

Substituted herein, unless specified otherwise, a hydrogen atom is a halogen group, an alkyl group of 1 to 30 carbon atoms, a haloalkyl group of 1 to 30 carbon atoms, an aryl group of 6 to 30 carbon atoms, a heteroaryl group of 2 to 30 carbon atoms, carbon atoms It means substituted with any one substituent selected from the group consisting of 1 to 18 alkoxy groups, and combinations thereof.

In addition, in the present specification, hetero means a carbon atom substituted with any one hetero atom selected from the group consisting of N, O, S, and P unless otherwise specified.

The liquid crystal photo-alignment agent can impart orientation to the surface of the film by irradiation with polarized ultraviolet light for a short time, which can be said to be innovative in terms of effects and economy compared to conventional methods. In addition, since the uniform inorganic alignment layer made of Si-O ₂ can be formed through the liquid crystal photoalignment agent, material instability of the organic alignment layer made of the existing polyimide or polyamic acid, that is, thermal decomposition and elution by ion impurities It can be free from problems such as. Therefore, the liquid crystal photoalignment film manufactured using the liquid crystal photoalignment agent has excellent performances such as long-term reliability, high voltage retention (VHR), pretilt angle stability, uniform liquid crystal photoalignment, and chemical resistance.

Any one first alkoxy silane compound selected from the group consisting of the compounds represented by Formulas 1 to 3, and combinations thereof and the second alkoxy silane compounds represented by Formula 4 may be polymerized in an optimal combination, thereby To maximize.

The polysiloxane preferably contains 5 to 95 mole% of any one alkoxy silane compound selected from the group consisting of compounds represented by Formulas 1 to 3, and combinations thereof with respect to the entire polysiloxane. As the second alkoxy silane compound, the compound represented by Chemical Formula 4 is preferably included in an amount of 5 to 95 mol%.

In addition, the polysiloxane preferably contains 10 to 70 mol% of the compound represented by Formula 1 with respect to the entire polysiloxane, and preferably includes 0.01 to 10 mol of the compound represented by Formula 2, It is preferable to include 5 to 30 mol% of the compound represented by the formula (3). The compound represented by the formula (4) is preferably included in 5 to 80 mol%.

Hereinafter, the specific form of the said alkoxy silane compound, and the function and effect of each are demonstrated in detail.

In Formula 1, the alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, or a pentoxy group. Preferred examples of the alkoxy silane compound represented by the formula (1) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane and the like, and furthermore, tetramethoxysilane or tetraethoxysilane It can be used preferably. The compounds may also be used in combination as a mixture of two or more.

When the polysiloxane is polymerized with the tetraalkoxy silane represented by the above formula (1), the degree of crosslinking of the polymer becomes dense and stable, so that the reliability of the alignment film can be greatly increased, and it is preferable to introduce a high content into the polymer. However, when the tetraalkoxy silane is included in a high content, the chemical resistance-solvent resistance of the alignment layer is increased, thereby making it insoluble in the stripper solvent and thus making it impossible to rework.

In Formula 2, one of the four R _{2 is} selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, and three are hydroxy and 1 carbon atom. Alkoxy of 5 to 5, and an aryloxy group of 6 to 12 carbon atoms. Alternatively, _two of the four R ₂ may be each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, and each two are independently Hydroxy, alkoxy having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms.

When said R <_2> is a C1-C18 alkyl group or a fluoroalkyl group, it is more preferable that the said alkyl group is a C8-18 long-chain alkyl group.

As the unsubstituted alkyl group, a hexyl group, heptyl group, octyl group, dodecyl group, hexadecyl group, octadecyl group or the like can be preferably used. As the fluoroalkyl group, trifluoropropyl group, heptafluoropentyl group, heptafluoroisopentyl group, tridecafluorooctyl group, or heptadecafluorodecyl group can be preferably used.

Preferred examples of the alkoxy silane represented by Formula 2 are hexyltrimethoxysilane, hexyltriethoxysilane, heptyltrimethoxysilane, heptyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, dode Unsubstituted alkyltrialkoxy silanes such as siltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, or octadecyltriethoxysilane are preferred. Can be used.

In addition, preferred examples of the alkoxy silane represented by Formula 2 include trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, heptafluoropentyltrimethoxysilane, heptafluoropentyltriethoxysilane, Fluoroalkyl trialkoxy silanes such as tridecafluorooctyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, or heptadecafluorodecyltriethoxysilane are preferred. Can be used.

The trialkoxy silane having the long-chain alkyl group plays a key role in determining the alignment and pretilt angle of the liquid crystal, but when used in an appropriate amount or more, the electrical properties and reliability of the alignment layer are deteriorated, so that the liquid crystal photo-alignment characteristics are not compromised. It is desirable to minimize the amount used.

In the formula (3), the alkoxy group is preferably an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, or a pentoxy group.

R ₃ is any one selected from the group consisting of an alkylene group or fluoroalkylene group having 1 to 8 carbon atoms, and an arylene group or fluorarylene group having 6 to 20 carbon atoms, and n is preferably an integer of 0 to 8. More preferably, R ₃ is a methylene group or a phenylene group.

Preferred examples of the alkoxy silane compound represented by Formula 3 include hexa methoxy disilane, bis trimethoxy disilyl methane, bis trimethoxy dissilyl ethane, bis trimethoxy dissilyl propane, bis trimethoxy dissilyl butane , Bis trimethoxy disilyl pentane, bis trimethoxy disilyl hexane, bis trimethoxy disilyl heptane, bis trimethoxy dissilyl octane, bis triethoxy dissilyl methane, bis triethoxy dissilyl ethane, bis Triethoxy dissilyl propane, bis triethoxy disilyl butane, bis triethoxy dissilyl pentane, bis triethoxy dissilyl hexane, bis triethoxy dissilyl heptane, bis triethoxy dissilyl octane, bis trie Toxy disilyl benzene, etc. can be used preferably.

The cinnamate group of Formula 4 is preferably derived from a compound represented by the following formula (5).

[Chemical Formula 5]

(In Chemical Formula 5,

R ₇₄ is any one selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 1 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. One substituent, n ₇₄ is an integer of 0 to 4,

R ₇₅ to R ₇₇ are each independently selected from a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. One substituent,

The alkyl group substituted in R ₇₅ to R ₇₇ is an alkyl group in which a hydrogen atom is substituted with any substituent selected from the group consisting of a hetero atom and a cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And any one alkyl group selected from the group consisting of a combination thereof,

R ₇₃ is a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylaryl group having 7 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, substituted or unsubstituted Selected pyrimidinyl group, substituted or unsubstituted pyridinyl group, substituted or unsubstituted thiophenyl group, substituted or unsubstituted furanyl group, substituted or unsubstituted naphthyl group, and substituted or unsubstituted phenyl group. Which is any substituent,

The alkyl group substituted at R ₇₃ is an alkyl group substituted with any substituent selected from the group consisting of a halogen and a cyano group with a hydrogen atom; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And any one alkyl group selected from the group consisting of a combination thereof,

The substituted alkylaryl group for R _{73 is selected} from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-, in which at least one non-adjacent CH ₂ group of the alkylaryl group is selected. An alkylaryl group substituted with any one substituent)

The chalcone group of Formula 4 is preferably derived from a compound represented by the following formula (6).

[Formula 6]

(In Chemical Formula 6,

R ₈₁ and R ₈₂ each independently represent a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 1 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. One substituent selected from the group consisting of, n ₈₁ , and n ₈₂ are each independently an integer of 0 to 5,

R ₈₃ and R ₈₄ are each independently any substituent selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, and a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms,

The alkyl group substituted in R ₈₃ and R ₈₄ is an alkyl group wherein a hydrogen atom is substituted with any substituent selected from the group consisting of a halogen atom and a cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And a combination of any one of the alkyl groups selected from the group consisting of)

The coumarin group of Formula 4 is preferably derived from a compound represented by the following formula (7).

[Formula 7]

(In Chemical Formula 7,

R ₉₂ is any one selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 1 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. Is a substituent of, n ₉₂ is an integer of 0 to 5,

R ₉₃ and R ₉₄ each independently represent a substituent selected from a hydrogen atom, a halogen atom, a cyano group, and a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms,

The alkyl group substituted in R ₉₃ and R ₉₄ is an alkyl group in which a hydrogen atom is substituted with any substituent selected from the group consisting of a halogen atom and a cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And a combination of any one of the alkyl groups selected from the group consisting of)

The alkoxy silane compound having a photoreactor such as a cinnamate group, a chalcone group, or a coumarin group has a double bond open during irradiation with ultraviolet rays, and optical crosslinking is performed. According to the crosslinking reaction is given to give a constant orientation.

In the polymerization of the polysiloxane, the carboxylic acid and the alcohol are first added to a reactor equipped with a reflux device, heated to a temperature of 30 to 80 ° C., and stirred for 10 minutes or more to sufficiently dissolve the carboxylic acid in solid form.

The carboxylic acid may be used as long as it is a carboxylic acid capable of reacting with alcohol to form an ester and generating water (H ₂ O). As the carboxylic acid, divalent dicarboxylic acid such as oxalic acid, or monovalent carboxylic acid such as acetic acid may be used in consideration of reactivity.

The alcohol can be used as long as it does not precipitate polysiloxane or silanol produced while polymerizing the silane compound. As said alcohol, monohydric alcohols, such as methanol, propanol, butanol, pentanol, hexanol, hexylol, heptylol, octylol, dihydric alcohols, such as propane diol and butane diol, etc. can be used preferably.

The alcohol may also be used, such as glycol, and examples thereof include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene. Glycol monoethyl ether, hexylene glycol and the like can be preferably used.

Moreover, it is also possible to mix and use 2 or more types of said alcohols and glycols. However, when the solvent is too large, the polymerization reaction system may be very complicated, difficult in terms of reaction control or stabilization, and the solvent composition ratio may be difficult or unpredictable when preparing polysiloxane.

In addition, since the silane compounds generally have ethoxy or methoxy groups to generate ethanol or methanol as a result of condensation polymerization, it is preferable to use methanol or ethanol rather than alcohol of too different properties. In addition, depending on the type of alkoxy silane compound, ethanol is most preferred because of low solubility in methanol during polymerization.

Through the polymerization process as described above, it is possible to obtain a polysiloxane having a main chain having a SiO ₂ structure of about 3000 to 18000 weight average molecular weight. The average molecular weight of the polysiloxane can be easily controlled by increasing or decreasing the reaction temperature, the reaction time, the concentration of the alkoxy silane monomer, the content of oxalic acid, and the like.

After polymerization, the polysiloxane is dissolved in alcohol or in a colloidal state. Since ethanol has a low boiling point, which is not preferable as a coating solvent, it is preferable to remove it and replace it with another solvent. When the alcohol is replaced with another solvent, there is a method of precipitating a solid content using hexane or the like, filtering the redissolved solution and adding a high boiling point solvent to be substituted, and then distilling the alcohol off.

In the polysiloxane, the alkoxy group is substituted with a hydrogen atom during the polymerization to become a hydroxyl group, which is again dehydrated through condensation polymerization to form a Si-O-Si bond, so that 30 to 60% of the solid content before the polymerization and the solid content after the polymerization is completed. A difference in degree may occur. Therefore, since the normal polysiloxane is composed of SiO ₂ , it is possible to infer a certain amount of the solid content of the polysiloxane by calculating the number of Si moles of the initial silane monomer, but the polysiloxane solution is 20 to 60 minutes in a 100-200 ° C. convection oven. It is more preferable to measure the residual amount of solid content obtained by drying with a balance.

The solid content of the polysiloxane for use as the liquid crystal photo-alignment agent is preferably 1 to 20% by weight, but more preferably 3 to 8% by weight of solids in order to form a uniform film within 1000 kPa during coating.

The solvent includes N-methyl-2-pyrrolidone, N, N-dimethyl acetamide, N, N-dimethyl formamide, dimethyl sulfoxide, γ-butyrolactone, and meta cresol, phenol, halogenated phenol, and the like. A tall solvent etc. can be used preferably.

In this case, the solvent further comprises any one selected from the group consisting of N-methyl-2-pyrrolidone, butyl cellosolve, hexylene glycol, butylene glycol, propylene glycol, ethylene glycol, and combinations thereof. It is preferable. In addition, the butyl cellosolve, etc. is preferably included in 5 to 50% by weight, more preferably in 10 to 30% by weight based on the total weight of the solvent. When the content of the butyl cellosolve and the like is within the above range, it is preferable in that the drying rate is increased when the liquid crystal photo-alignment agent is applied and the flatness of the film is improved.

The solvent may further include an alcohol, ketone, ester, ether, hydrocarbon, or halogenated hydrocarbon, which is a poor solvent, in an appropriate ratio as long as the soluble polyimide polymer is not precipitated. This is because the poor solvents lower the surface energy of the liquid crystal photoalignment agent to improve spreadability and flatness during application.

The poor solvent is preferably used in the range of 1 to 90% by volume with respect to the total solvent, more preferably in the range of 1 to 70% by volume.

Specific examples of the poor solvent include methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, acetone, methyl ethyl ketone, cyclohexanone, methyl acetate, ethyl acetate, acetate Butyl, diethyl oxalate, malonic ester, diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol phenyl ether, ethylene glycol phenyl methyl ether, ethylene glycol phenyl ethyl ether, ethylene glycol dimethylethyl, diethylene Glycol Dimethylethyl, Diethylene Glycol Ether, Diethylene Glycol Monomethyl Ether, Dietelin Glycol Monoethyl Ether, Diethylene Glycol Monomethyl Ether Acetate, Diethylene Glycol Monoethyl Ether Acetate, Ethylene Glycol Methyl Ether Acetate, Ethylene Glycol Ethyl Ether Acete , 4-hydroxy-4-methyl-2-pentanone, 2-hydroxy ethyl propionate, 2-hydroxy-2-methyl ethyl propionate, ethoxy acetate, ethyl hydroxy acetate, 2-hydroxy-3 -Methyl methyl butyrate, methyl 3-methoxy propionate, ethyl 3-methoxy propionate, ethyl 3-ethoxy propionate, methyl 3-ethoxy propionate, methyl methoxy butanol, ethyl methoxy butanol, methyl ethoxy butanol, ethyl Ethoxy butanol, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichloro butane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, and And any one selected from the group consisting of a combination of these.

The content of the solvent in the composition for forming a liquid crystal photoalignment film is not particularly determined, but the solid content of the liquid crystal photoalignment agent is 1 to 30% by weight, preferably 3 to 15% by weight, more preferably 5 to 10% by weight. Use if possible. When the content of the solid content is less than 1% by weight, there may be a problem that the uniformity of the film is lowered under the influence of the substrate surface during printing, and when the content of the solid content exceeds 30% by weight, the uniformity of the film formed during printing is reduced by the high viscosity. May be lowered and transmittance may be lowered.

The composition for forming a liquid crystal photoalignment film may include at least one epoxy compound having 2 to 4 epoxy functional groups in order to improve reliability and electro-optic properties. The epoxy compound is preferably contained in an amount of 0.01 to 50 parts by weight, more preferably 1 to 30 parts by weight based on 100 parts by weight of the liquid crystal photoalignment agent. When the content of the epoxy compound exceeds 50 parts by weight may reduce the printability or flatness when applied to the substrate, when less than 0.01 parts by weight, the effect of adding the epoxy compound is insignificant.

Specific examples of the epoxy compound include N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane (TGDDM), N, N, N', N'-tetraglycidyl -4,4'-diaminodiphenylethane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylpropane, N, N, N', N'-tetragly Cydyl-4,4'-diaminodiphenylbutane, N, N, N ', N'-tetraglycidyl-4,4'-diaminobenzene, and the like, but are not limited thereto.

In addition, the composition for forming a liquid crystal photoalignment film may further use a silane coupling agent or a surfactant to improve adhesion to the substrate and to improve flatness and film coating properties.

The liquid crystal photoalignment film-forming composition may be applied to a substrate to form a liquid crystal photoalignment film. As a method of apply | coating the said liquid crystal photoalignment film formation composition to the said board | substrate, a spin coat method, the flexographic printing method, the inkjet method, etc. are mentioned. Among them, the flexographic printing method can be preferably used because it is excellent in uniformity of the formed coating film and easy to enlarge.

The substrate can be used without particular limitation as long as it is a substrate having high transparency, and a plastic substrate such as a glass substrate or an acrylic substrate or a polycarbonate substrate can be used. Moreover, it is preferable to use the board | substrate with which the ITO electrode etc. for liquid crystal drive were formed from a viewpoint of the simplification of a manufacturing process.

The composition for forming a liquid crystal photoalignment film is uniformly coated on a substrate in order to increase the uniformity of the coating film, and then for 1 to 100 minutes at room temperature to 200 ° C, preferably 30 to 150 ° C, more preferably 40 to 120 ° C. It is preferable to perform temporary drying. By adjusting the volatilization degree of each component of the composition for forming a liquid crystal photoalignment film through the temporary drying, a uniform and uneven coating film can be obtained.

Thereafter, baking is carried out at a temperature of 80 to 300 ° C, preferably 120 to 280 ° C for 5 to 300 minutes to completely evaporate the solvent to form a liquid crystal photoalignment film.

The liquid crystal photoalignment film formed by the above-described method is used in a liquid crystal display without performing uniaxial alignment treatment by polarized ultraviolet irradiation or in some applications such as a vertical alignment film.

The liquid crystal photoalignment film according to the embodiment of the present invention may be subjected to uniaxial alignment treatment by exposing for 0.1 to 180 minutes at an energy of 10 mJ to 5000 mJ.

According to another embodiment of the present invention, a display device including the liquid crystal photoalignment layer is provided. It is preferable that the said display device is a liquid crystal display device.

1 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

Referring to FIG. 1, the liquid crystal display 1 according to the exemplary embodiment of the present invention includes a lower panel 100, an upper panel 200, and a liquid crystal layer 3.

The lower panel 100 includes a gate conductor including a plurality of gate lines (not shown) and a plurality of storage electrodes 133 on an upper surface of the first substrate 110. . On the gate conductor, a gate insulating layer 140, a plurality of semiconductors 154, a plurality of pairs of ohmic contacts 163 and 165, a plurality of source electrodes 173, And a plurality of drain electrodes 175 are formed in this order.

One gate electrode 124, one source electrode 173, and one drain electrode 175 together with the semiconductor 154 form one thin film transistor (TFT).

A passivation layer 180 is formed on the exposed portion of the semiconductor 154, the source electrode 173, the drain electrode 175, and the gate insulating layer 140. A plurality of pixel electrodes 191 are formed on the passivation layer 180.

Next, the upper panel 200 will be described.

In the upper panel 200, a light blocking member 220 is formed on the second substrate 210. A plurality of color filters 230 are formed on the second substrate 210 and the light blocking member 220, and an overcoat 250 is formed on the color filters 230. The overcoat 250 may prevent the color filter 230 from being exposed to the liquid crystal layer 3, and the overcoat 250 may be omitted.

The first liquid crystal photoalignment layer 12 and the second liquid crystal photoalignment layer 22 are formed on the pixel electrode 191 of the lower panel 100 and on the common electrode 270 of the upper panel 200, respectively. The first liquid crystal photoalignment layer 12 and the second liquid crystal photoalignment layer 22 are manufactured using the liquid crystal photoalignment agent according to the embodiment of the present invention.

In FIG. 1, the liquid crystal photoalignment layers 12 and 22 are formed on both the lower panel 100 and the upper panel 200, but the liquid crystal photoalignment layers 12 and 22 may be formed on the upper panel 200 or the upper panel 200. It may be formed only in any one of the lower panel 100.

Hereinafter, specific embodiments of the present invention will be described. However, the embodiments described below are merely for illustrating or explaining the present invention in detail, and thus the present invention is not limited thereto.

( Synthetic example : Polysiloxane  Produce)

( Synthetic example  One)

160.5 g of ethanol was added to a brown four-necked flask connected with a reflux condenser to dissolve 46.7 g of oxalic acid while stirring, and heated at 60 ° C. for 30 minutes to confirm that oxalic acid was sufficiently dissolved in ethanol. Thereafter, a mixture of 8.5 g of bistriethoxysilyl methane, 44.8 g of tetraethylorthosilicate, 3.8 g of octadecyltrimethoxysilane, and 28.7 g of trimethoxysilylchalcone were slowly added to the oxalic acid-ethanol solution over 1 hour. After dropping, the mixture was maintained for 4 hours. After cooling, 175 g of hexylene glycol was added thereto, followed by distillation to remove ethanol to obtain a 10% by weight polysiloxane solution having a weight average molecular weight of 13200. The resulting resin was named PSA18-CH.

( Synthetic example  2)

160.5 g of ethanol was added to a brown four-necked flask connected with a reflux condenser, and while stirring, 46.7 g of oxalic acid was dissolved and heated to 60 ° C., and then maintained for 30 minutes to confirm that oxalic acid was sufficiently dissolved in ethanol. Thereafter, a mixture of 8.5 g of bistriethoxysilyl methane, 44.8 g of tetraethylorthosilicate, 3.8 g of octadecyltrimethoxysilane, and 30.1 g of trimethoxysilylcinnamate was added to the oxalic acid-ethanol solution over 1 hour. After slowly dropping, the mixture was maintained for 4 hours. After cooling, 172.5 g of hexylene glycol was added thereto, followed by distillation to remove ethanol to obtain a 10% by weight polysiloxane solution having a weight average molecular weight of 12400. The resulting resin was named PSA18-CN.

( Synthetic example  3)

160.5 g of ethanol was added to a brown four-necked flask connected with a reflux condenser to dissolve 46.7 g of oxalic acid while stirring, and after heating to 60 ° C., the oxalic acid was sufficiently dissolved in ethanol. Thereafter, a mixture of 8.5 g of bistriethoxysilyl methane, 44.8 g of tetraethylorthosilicate, 3.8 g of octadecyltrimethoxysilane, and 23.6 g of trimethoxysilylcinnamate were added to the oxalic acid-ethanol solution over 1 hour. After slowly dropping, the mixture was maintained for 4 hours. After cooling, 168.3 g of hexylene glycol was added thereto, followed by distillation to remove ethanol to obtain a 10% by weight polysiloxane solution having a weight average molecular weight of 13600. The resulting resin was named PSA18-CU.

(compare Synthetic example  One)

Four-necked flask equipped with a stirrer, a thermostat, a nitrogen gas injection device, and a cooler, while passing nitrogen under dark conditions, with 0.5 mole of phenylenediamine and diamino benzoic acid 4- (2-ethoxycarb represented by the following formula (8): 0.5 mol of carbonyl-vinyl) -phenyl ester was added thereto, and N-methyl-2-pyrrolidone was added thereto to prepare a mixed solution.

[Formula 8]

(N = 2 in Formula 8)

1.0 mol of 1,2,3,4-cyclobutanetetracarboxylic dianhydride in the solid state was added to the mixed solution, followed by vigorous stirring. The solid content at this time is 20% by weight, the reaction was carried out for 24 hours while maintaining the temperature at 30 ℃ to 80 ℃ to prepare a polyamic acid solution. 3.0 mol of acetic anhydride and 5.0 mol of pyridine were added to the prepared polyamic acid solution, and the temperature was raised to 80 ° C., followed by reaction for 6 hours, and the catalyst and solvent were removed by vacuum distillation to obtain 20% of a solid soluble polyimide. Photopolymers were prepared.

N-methyl-2-pyrrolidone, which is an organic solvent, was added to the prepared soluble polyimide photopolymer and stirred at room temperature for 24 hours to prepare a soluble photo-oriented polyimide resin (PSPI-1) having a solid content of 10% by weight.

Example: Preparation of Liquid Crystal Photoalignment Agent

(Example 1)

50 g of butyl cellosolve (BC) was added to 50 g of the PSA18-CH solution having a solid content of 10.0 wt% obtained in Synthesis Example 1, stirred, and filtered through a 0.2 μm filter to obtain a liquid crystal photo-alignment agent having a solid content of 5.0 wt% (hereinafter AL-PSA18-CH).

(Example 2)

50 g of BC was added to 50 g of the PSA18-CN solution having a solid content of 10.0 wt% obtained in Synthesis Example 2, followed by stirring with a filter having a particle size of 0.1 μm to obtain a liquid crystal photo-alignment agent having a solid content of 5.0 wt% (hereinafter AL-PSA18-CN). ).

(Example 3)

50 g of BC was added to 50 g of the PSA18-CU solution having a solid content of 10.0 wt% obtained in Synthesis Example 3, followed by stirring with a filter having a particle diameter of 0.1 μm to obtain a liquid crystal photo-alignment agent having a solid content of 5.0 wt% (hereinafter AL-PSA18-CU). ).

(Comparative Example 1)

20 g of N-methyl-2-pyrrolidone (NMP) and 30 g of BC were added to 50 g of the PSPI-1 solution having a solid content of 10.0% by weight, obtained in Comparative Synthesis Example 1, and then filtered through a filter having a particle size of 0.1 μm. A weight% liquid crystal photoalignment agent was obtained (hereinafter referred to as AL-PSPI-1).

(Measure printability and ease of rework)

The liquid crystal photo-alignment agent prepared in Examples 1 to 3 and Comparative Example 1 was applied onto ITO glass having a size of 10 cm × 10 cm, spin-coated to be uniformly 0.1 μm thick, and then heated to 80 ° C. on a hot plate. After desolvation of the sample, it was sampled through a curing process of 210 ℃.

The printability of the liquid crystal photoalignment agent was evaluated by observing spreading and curling characteristics of the prepared sample through visual and optical microscopy. The printability evaluation results are shown in Table 1 below.

Further, the copper sample used for the printability evaluation in order to evaluate reworkability, ie stripping property by solvent, was applied to TS-204, which is an alignment film rework solvent of Korea Polyol Co., Ltd. It was measured by dipping at ℃ ℃ time to completely remove the liquid crystal photo-alignment film, the results are shown in Table 1 below.

(Liquid crystal Optical orientation  Measure)

In order to evaluate the liquid crystal photoalignment of the liquid crystal photoalignment agent, a liquid crystal cell was produced and used. The manufacture of the liquid crystal cell is as follows.

The ITO glass substrate was patterned using a photolithography process to remove other portions of ITO, leaving only 1.5 cm × 1.5 cm square ITO shapes and electrode ITO shapes for voltage application.

The liquid crystal photo-alignment agent prepared in Examples 1 to 3, and Comparative Example 1 was applied to the patterned ITO substrate, spin-coated to a thickness of 0.1 μm, and then subjected to curing at 70 ° C. and 210 ° C.

The ITO substrate that has undergone the curing process is exposed to the opposite direction (90 degrees for VA mode) of the two substrates exposed at a predetermined angle and energy using an exposure machine (Ushio LPUV, UIS-S2021J7-YD01). Thereafter, square ITO shapes were joined up and down consistently while maintaining a cell gap of 4.75 mu m. In the exposure, a light source used a 2kW deep UV ramp (UXM-2000).

After filling the liquid crystal in the cell made in this way, the liquid crystal photo-alignment was observed using an orthogonally polarized optical microscope, the results are summarized in Table 1 below.

( Pretilt  Measure)

The liquid crystal cell for pretilt angle evaluation was manufactured separately from the above method so as to maintain the cell gap at 50 μm.

In order to measure the pretilt angles of the liquid crystal photoalignment agents prepared in Examples 1 to 3 and Comparative Example 1, a liquid crystal cell having a 50 μm cell gap was prepared and a crystal rotation method was used. The pretilt angle measurement results are shown in Table 1 below.

(Measurement of electrical and optical characteristics)

Electrical and optical properties of the liquid crystal photoalignment agent were evaluated by measuring the voltage-transmittance curve, the voltage holding ratio, and the residual DC voltage using a liquid crystal cell having a 4.75 μm cell gap.

The electrical and optical characteristics of the voltage-transmittance curve, the voltage holding ratio, and the residual DC voltage are briefly described as follows.

The voltage-transmittance curve is one of the important electrical and optical characteristics, which is one of the characteristics that determine the driving voltage of the liquid crystal display. The voltage is measured in transmittance while the voltage is applied to the liquid crystal cell. The curve is normalized with the amount of light in the state at 0%.

The voltage holding ratio refers to the degree to which the liquid crystal layer in the state of floating with the external power source is charged during the non-selection period in the active driving type TFT-LCD, and a value close to 100% is ideal.

The residual DC voltage refers to a voltage applied to the liquid crystal layer even when no impurities are applied to the alignment layer, so that the ionized liquid crystal layer is absorbed by the alignment layer. As a method of measuring the residual DC voltage, a method using flicker and a method using a capacitance change curve (C-V) of the liquid crystal layer according to DC voltage are common.

In addition, in order to evaluate the reliability of the liquid crystal photoalignment film during long-term driving, after applying a voltage at a high temperature for 500 hours or more, the degree of reduction of the voltage holding ratio was measured.

The results of the electrical and optical properties of the liquid crystal photoalignment agent using the liquid crystal cell are shown in Table 2 below.

TABLE 1

Liquid crystal alignment agent Printability Reworkability (min) Liquid crystal orientation Wire diameter square (˚) Example 1 Good 2 Good 89.8 Example 2 Good 4 Good 89.7 Example 3 Good 3 Good 89.1 Comparative Example 1 Bad 10 Good 86.5

TABLE 2

Liquid crystal photoalignment agent Voltage retention rate (%) Residual DC
(by CV) Voltage retention rate drop
(%) Room temperature (25 ℃) High temperature (60 ℃) Example 1 99.2 99.0 125.0 1.2 Example 2 99.1 98.4 85.0 1.7 Example 3 99.1 98.7 150.0 3.1 Comparative Example 1 99.0 94.5 250.0 10.5

Referring to Table 1, it can be seen that the liquid crystal locator prepared in Examples 1 to 3 can be used as a liquid crystal photoalignment film because the printability, orientation, and pretilt angle are good. In addition, the liquid crystal photo-alignment agent prepared in Examples 1 to 3 can be confirmed that the reworkability is very excellent compared to the liquid crystal photo-alignment agent of Comparative Example 1.

Referring to Table 2, it can be seen that the liquid crystal photoalignment agents prepared in Examples 1 to 3 are all 99% or more in voltage retention at low temperature, and 98% or more in voltage retention at high temperature. On the other hand, it can be seen that the liquid crystal photoalignment agent prepared in Comparative Example 1 has a very low voltage holding ratio at high temperature.

In addition, it can be seen that the liquid crystal photoalignment agent prepared in Examples 1 to 3 has a low residual DC, whereas the liquid crystal photoalignment agent prepared in Comparative Example 1 has a very high residual DC.

The voltage holding ratio and the residual DC serve as a criterion for evaluating the afterimage characteristic of the liquid crystal photoalignment layer, and the higher the voltage holding ratio and the lower the residual DC, the better the afterimage characteristic. Therefore, it can be seen that the liquid crystal photoalignment agent prepared in Examples 1 to 3 is superior to the afterimage property than the liquid crystal photoalignment agent prepared in Comparative Example 1.

The present invention is not limited to the above embodiments, but may be manufactured in various forms, and a person skilled in the art to which the present invention pertains has another specific form without changing the technical spirit or essential features of the present invention. It will be appreciated that the present invention may be practiced as. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

1 is a cross-sectional view of a liquid crystal display according to an exemplary embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

1: liquid crystal display device 3: liquid crystal layer

12: first liquid crystal photoalignment film 22: second liquid crystal photoalignment film

100: lower display panel 110: first substrate

175: drain electrode 191: pixel electrode

200: upper display panel 210: second substrate

230: color filter 270: common electrode

Claims (12)

Any one first alkoxy silane compound selected from the group consisting of compounds represented by Formulas 2 and 3 or A first alkoxy silane compound consisting of a mixture of any one selected from the group consisting of a compound represented by the formula (1) and a compound represented by the formula (2) and 3 and A second alkoxy silane compound represented by the following formula (4) Polysiloxane polymer prepared by polymerizing; And menstruum Liquid crystal photo-alignment agent comprising a. [Formula 1] Si (R ₁ ) ₄ (In the formula 1, The four R ₁ are each independently a substituent selected from the group consisting of a hydroxy, an alkoxy group having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms) [Formula 2] Si (R ₂ ) ₄ (In Formula 2, The four R _{2 's} each independently represent a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, or a fluoroalkyl group, an aryl group having 6 to 30 carbon atoms, or a fluoraryl group, hydroxy, an alkoxy group having 1 to 5 carbon atoms, and 6 to 12 carbon atoms. Is any one substituent selected from the group consisting of aryloxy groups, One or _two of the four R ₂ are each independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms or a fluoroalkyl group, an aryl group having 6 to 20 carbon atoms, or a fluoraryl group, and 2 or 3 are hydroxy Oxy, alkoxy having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms). (3) (R ₄ ) ₃ Si- (R ₃ ) _n -Si (R ₄ ) ₃ (In Chemical Formula 3, R ₃ is any one selected from the group consisting of an alkylene group or a fluoroalkylene group having 1 to 8 carbon atoms, an arylene group or a fluorarylene group having 6 to 20 carbon atoms, and n is an integer of 0 to 8, Each of R ₆ is independently a substituent selected from the group consisting of hydroxy, alkoxy having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms) [Formula 4] Si (R ₅ ) ₄ (In Formula 4, The four R ₅ are each independently a group consisting of a coumarin group, a chalcone group, a cinnamate group, a hydroxy group, an alkoxy group having 1 to 5 carbon atoms, and an aryloxy group having 6 to 12 carbon atoms. Any substituent selected from One or two of the four R ₅ are each independently selected from the group consisting of a cumarine group, a chalcone group, and a cinnamate group, and two or three groups thereof are hydroxy and 1 to 3 carbon atoms. Alkoxy of 5 and an aryloxy group having 6 to 12 carbon atoms) The method of claim 1, The polysiloxane polymer Any one first alkoxy silane compound selected from the group consisting of compounds represented by Formulas 2 and 3 or First alkoxy silane compound consisting of a mixture of any one selected from the group consisting of a compound represented by the formula (1) and a compound represented by the formula (2) and 5 to 95 mol%, Liquid crystal photo-alignment agent comprising a second alkoxy silane compound represented by the formula (4) in 5 to 95 mol%. The method of claim 1, The polysiloxane polymer is 10 to 70 mol% of the compound represented by Formula 1, 0.01 to 10 mol% of the compound represented by Formula 2, 5 to 30 mol% of the compound represented by Formula 3, and represented by Formula 4 Liquid crystal photo-alignment agent containing 5 to 80 mol% of a compound. The method of claim 1, The compound represented by the formula (1) is a liquid crystal photo-alignment agent which is any one of the tetraalkoxysilane selected from the group consisting of tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, and combinations thereof . The method of claim 1, The compound represented by the formula (2) is hexyltrimethoxysilane, hexyltriethoxysilane, heptyltrimethoxysilane, heptyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, dodecyltrimethoxysilane , Unsubstituted any one selected from the group consisting of dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, and combinations thereof Alkyltrialkoxysilanes; Trifluoropropyltrimethoxysilane, trifluoropropyltriethoxysilane, heptafluoropentyltrimethoxysilane, heptafluoropentyltriethoxysilane, tridecafluorooctyltrimethoxysilane, tridecafluoro An alkyltrialkoxysilane substituted with any one of fluorine selected from the group consisting of octyltriethoxysilane, heptadecafluorodecyltrimethoxysilane, heptadecafluorodecyltriethoxysilane, and combinations thereof; And Liquid crystal photo-alignment agent which is any alkyltrialkoxysilane selected from the group consisting of these combinations. The method of claim 1, The silane compound represented by the formula (3) is hexa methoxy disilane, bis trimethoxy disilyl methane, bis trimethoxy dissilyl ethane, bis trimethoxy dissilyl propane, bis trimethoxy dissilyl butane, bis trimeth Methoxy disilyl pentane, bis trimethoxy disilyl hexane, bis trimethoxy disilyl heptane, bis trimethoxy dissilyl octane, bis triethoxy dissilyl methane, bis triethoxy dissilyl ethane, bis triethoxy di Silyl propane, bis triethoxy dissilyl butane, bis triethoxy disylyl pentane, bis triethoxy dissilyl hexane, bis triethoxy dissilyl heptane, bis triethoxy dissilyl octane, bis triethoxy dissilyl benzene And liquid crystal photo-alignment agent which is any one selected from the group consisting of these. The method of claim 1, The cinnamate group is a liquid crystal photo-alignment agent is derived from a compound represented by the formula (5). [Chemical Formula 5]

(In Chemical Formula 5, R ₇₄ is any one selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 1 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. One substituent, n ₇₄ is an integer of 0 to 4, R ₇₅ to R ₇₇ are each independently selected from a hydrogen atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. One substituent, The alkyl group substituted in R ₇₅ to R ₇₇ is an alkyl group in which a hydrogen atom is substituted with any substituent selected from the group consisting of a hetero atom and a cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And any one alkyl group selected from the group consisting of a combination thereof, R ₇₃ is a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylaryl group having 7 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, substituted or unsubstituted Selected pyrimidinyl group, substituted or unsubstituted pyridinyl group, substituted or unsubstituted thiophenyl group, substituted or unsubstituted furanyl group, substituted or unsubstituted naphthyl group, and substituted or unsubstituted phenyl group. Which is any substituent, The alkyl group substituted in R ₇₃ is an alkyl group in which a hydrogen atom is substituted with any substituent selected from the group consisting of halogen and cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And any one alkyl group selected from the group consisting of a combination thereof, The substituted alkylaryl group for R _{73 is selected} from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-, in which at least one non-adjacent CH ₂ group of the alkylaryl group is selected. An alkylaryl group substituted with any one substituent, The substituted Iran hydrogen atom is a halogen group, an alkyl group having 1 to 30 carbon atoms, a haloalkyl group having 1 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and Means substituted with any one of substituents selected from the group consisting of a combination of these) The method of claim 1, The chalcone group is a liquid crystal photo-alignment agent is derived from a compound represented by the following formula (6). [Formula 6]

(In Chemical Formula 6, R ₈₁ and R ₈₂ each independently represent a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 1 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. One substituent selected from the group consisting of, n ₈₁ , and n ₈₂ are each independently an integer of 0 to 5, R ₈₃ and R ₈₄ are each independently any substituent selected from the group consisting of a hydrogen atom, a halogen atom, a cyano group, and a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, The alkyl group substituted in R ₈₃ and R ₈₄ is an alkyl group wherein a hydrogen atom is substituted with any substituent selected from the group consisting of a halogen atom and a cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And any one alkyl group selected from the group consisting of a combination thereof, The substituted Iran hydrogen atom is a halogen group, an alkyl group having 1 to 30 carbon atoms, a haloalkyl group having 1 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and Means substituted with any one of substituents selected from the group consisting of a combination of these) The method of claim 1, The coumarin group is a liquid crystal photo-alignment agent is derived from a compound represented by the following formula (7). [Formula 7]

(In Chemical Formula 7, R ₉₂ is any one selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 1 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 2 to 30 carbon atoms. Is a substituent of, n ₉₂ is an integer of 0 to 5, R ₉₃ and R ₉₄ each independently represent a substituent selected from a hydrogen atom, a halogen atom, a cyano group, and a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, The alkyl group substituted in R ₉₃ and R ₉₄ is an alkyl group in which a hydrogen atom is substituted with any substituent selected from the group consisting of a halogen atom and a cyano group; An alkyl group wherein at least one non-adjacent CH ₂ group of the alkyl group is substituted with any one substituent selected from the group consisting of -O-, -CO-O-, -O-CO-, and -CH = CH-; And any one alkyl group selected from the group consisting of a combination thereof, The substituted Iran hydrogen atom is a halogen group, an alkyl group having 1 to 30 carbon atoms, a haloalkyl group having 1 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, a heteroaryl group having 2 to 30 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and Means substituted with any one of substituents selected from the group consisting of a combination of these) The method of claim 1, The solvent is a liquid crystal photo-alignment agent containing 5 to 50% by weight of butyl cellosolve relative to the total solvent. The liquid crystal photoalignment film manufactured by apply | coating the liquid crystal photoalignment agent of any one of Claims 1-10 to a board | substrate. A liquid crystal display device comprising the liquid crystal photoalignment film according to claim 11.

Images