WO2023219112A1 - 新規なジアミン化合物、該ジアミンを用いて得られる重合体、液晶配向剤、液晶配向膜、及び液晶表示素子 - Google Patents
新規なジアミン化合物、該ジアミンを用いて得られる重合体、液晶配向剤、液晶配向膜、及び液晶表示素子 Download PDFInfo
- Publication number
- WO2023219112A1 WO2023219112A1 PCT/JP2023/017610 JP2023017610W WO2023219112A1 WO 2023219112 A1 WO2023219112 A1 WO 2023219112A1 JP 2023017610 W JP2023017610 W JP 2023017610W WO 2023219112 A1 WO2023219112 A1 WO 2023219112A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- liquid crystal
- dianhydride
- diamine
- group
- polymer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
- C07D209/02—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom condensed with one carbocyclic ring
- C07D209/44—Iso-indoles; Hydrogenated iso-indoles
- C07D209/48—Iso-indoles; Hydrogenated iso-indoles with oxygen atoms in positions 1 and 3, e.g. phthalimide
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D487/00—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00
- C07D487/02—Heterocyclic compounds containing nitrogen atoms as the only ring hetero atoms in the condensed system, not provided for by groups C07D451/00 - C07D477/00 in which the condensed system contains two hetero rings
- C07D487/04—Ortho-condensed systems
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G73/1042—Copolyimides derived from at least two different tetracarboxylic compounds or two different diamino compounds
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G73/00—Macromolecular compounds obtained by reactions forming a linkage containing nitrogen with or without oxygen or carbon in the main chain of the macromolecule, not provided for in groups C08G12/00 - C08G71/00
- C08G73/06—Polycondensates having nitrogen-containing heterocyclic rings in the main chain of the macromolecule
- C08G73/10—Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
- C08G73/1075—Partially aromatic polyimides
- C08G73/1078—Partially aromatic polyimides wholly aromatic in the diamino moiety
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K19/00—Liquid crystal materials
- C09K19/52—Liquid crystal materials characterised by components which are not liquid crystals, e.g. additives with special physical aspect: solvents, solid particles
- C09K19/54—Additives having no specific mesophase characterised by their chemical composition
- C09K19/56—Aligning agents
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1337—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers
- G02F1/13378—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by treatment of the surface, e.g. embossing, rubbing or light irradiation
- G02F1/133788—Surface-induced orientation of the liquid crystal molecules, e.g. by alignment layers by treatment of the surface, e.g. embossing, rubbing or light irradiation by light irradiation, e.g. linearly polarised light photo-polymerisation
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2219/00—Aspects relating to the form of the liquid crystal [LC] material, or by the technical area in which LC material are used
- C09K2219/03—Aspects relating to the form of the liquid crystal [LC] material, or by the technical area in which LC material are used in the form of films, e.g. films after polymerisation of LC precursor
Definitions
- the present invention relates to a novel diamine compound, a polymer obtained using the diamine, a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element.
- polyimide films are often used for liquid crystal alignment films used in liquid crystal display elements, and these polyimide films are made by coating a substrate with a polyimide precursor, such as a solution of polyamic acid or a solution of solvent-soluble polyimide. A method of coating and firing is used.
- This polyamic acid or solvent-soluble polyimide is generally synthesized by reacting a tetracarboxylic acid derivative such as a tetracarboxylic dianhydride with a diamine.
- a liquid crystal display element includes, for example, a liquid crystal layer sandwiched between an element substrate and a color filter substrate, a pixel electrode and a common electrode that apply an electric field to the liquid crystal layer, and a liquid crystal alignment film that controls the orientation of liquid crystal molecules in the liquid crystal layer. , thin film transistors (TFTs), etc. that switch electrical signals supplied to pixel electrodes.
- Driving methods for liquid crystal molecules include vertical electric field methods such as TN (Twisted Nematic) method and VA (Vertical Alignment) method, IPS (In-Plane Switching) method, and FFS (Fringe Field Switching).
- TN Transmission Nematic
- VA Very Alignment
- IPS In-Plane Switching
- FFS Frringe Field Switching
- Transverse electric field method such as Are known.
- the liquid crystal alignment film that is most widely used industrially is made of cotton, nylon, etc. It is manufactured by rubbing in one direction with a cloth such as polyester, which is a so-called rubbing process. Rubbing treatment is a simple, highly productive and industrially useful method.
- a photo-alignment method that imparts liquid crystal alignment ability by irradiating polarized radiation has become known as an alignment treatment method that replaces rubbing treatment. ing.
- photoalignment methods methods using photoisomerization reactions, methods using photocrosslinking reactions, methods using photodecomposition reactions, etc. have been proposed (see, for example, Non-Patent Document 1 and Patent Document 1).
- Patent Document 2 proposes a liquid crystal aligning agent using a diamine having a diaminodiphenylamine structure as a polyimide (precursor) raw material.
- liquid crystal display elements As the definition of liquid crystal display elements becomes higher, the level of the above-mentioned requirements is becoming higher, and a liquid crystal alignment film that can satisfy the above requirements is required. Furthermore, in liquid crystal display elements used for mobile applications such as smartphones, car navigation systems, and the like, the thickness of the substrate (eg, glass substrate, etc.) constituting the liquid crystal panel may be reduced from the viewpoint of weight reduction. For this reason, from the viewpoint of suppressing the abrasion of the liquid crystal alignment film that occurs as the substrate becomes thinner, a liquid crystal alignment film with high film strength is sometimes required. Furthermore, in the IPS system and FFS driving system, stability of liquid crystal alignment is also important.
- the substrate eg, glass substrate, etc.
- the polyimide (precursor) obtained using the diamine having the diphenylamine structure described in Patent Document 2 has the above-mentioned problems because the molecular weight of the polymer decreases significantly in the baking process when producing a liquid crystal alignment film. It was not possible to solve the problem satisfactorily.
- the first object of the present invention is to provide a novel diamine and a polymer obtained using the diamine. It is an object of the present invention to provide a liquid crystal aligning agent capable of obtaining a liquid crystal aligning film with a high voltage retention rate even after exposure, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element using the same. Further, it is an object of the present invention to provide a liquid crystal aligning agent capable of suppressing a decrease in the molecular weight of a polymer during baking when producing a liquid crystal aligning film, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element using the same. be.
- a liquid crystal aligning agent capable of obtaining a liquid crystal aligning film that has a high voltage retention rate, high film strength, and suppresses AC afterimage even after being exposed to high temperatures for a long time, and the liquid crystal aligning agent.
- An object of the present invention is to provide a liquid crystal alignment film obtained from a liquid crystal alignment film and a liquid crystal display element using the same.
- the present invention includes the following aspects.
- a diamine represented by any of the following formulas (d A -1) to (d A -6).
- the diamine component further includes a diamine having in its molecule at least one group selected from the group consisting of a urea bond, an amide bond, a carboxy group, and a hydroxy group.
- 4. The polymer according to 2 or 3 above, wherein the amount of the diamine described in 1 above is 5 mol% or more based on the diamine component. 5.
- the polymer is obtained by a polymerization reaction of the diamine component and the tetracarboxylic acid component, and the tetracarboxylic acid component contains a tetracarboxylic dianhydride or a derivative thereof.
- Polymers described. 6 The tetracarboxylic dianhydride or its derivative is an acyclic aliphatic tetracarboxylic dianhydride, an alicyclic tetracarboxylic dianhydride, an aromatic tetracarboxylic dianhydride, or a derivative thereof, The polymer described in 5 above. 7.
- the tetracarboxylic dianhydride or its derivative is Acyclic aliphatic tetracarboxylic dianhydride which is 1,2,3,4-butanetetracarboxylic dianhydride; 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3, 4-Cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4 -Cyclobutanetetracarboxylic dianhydride, 1,3-difluoro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-bis(trifluoromethyl)-1,2,3,4- Cyclobutanetetracarboxylic
- a liquid crystal aligning agent characterized by containing the polymer according to any one of items 2 to 7 above. 9. Furthermore, it contains at least one polymer (B) selected from the group consisting of a polyimide precursor obtained using the diamine component not containing the diamine described in 1 above, and a polyimide that is an imidized product of the polyimide precursor. , the liquid crystal aligning agent according to 8 above. 10. 9. The liquid crystal alignment according to 9 above, wherein the polymer (B) is obtained by a polymerization reaction of the diamine component and the tetracarboxylic acid component, and the tetracarboxylic acid component contains a tetracarboxylic dianhydride or a derivative thereof. agent. 11.
- Step (1) A step of applying the liquid crystal aligning agent according to any one of items 8 to 11 above onto a substrate.
- Step (2) A step of baking the applied liquid crystal aligning agent to obtain a film.
- Step (3) A step of subjecting the film obtained in step (2) to an alignment treatment 15.
- the diamine of the present invention when used as a raw material for a polymer constituting a liquid crystal alignment film, suppresses a decrease in the molecular weight of the polymer during firing and forms a liquid crystal alignment film that has a high voltage retention rate.
- a liquid crystal aligning agent, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a high-performance liquid crystal display element equipped with the liquid crystal aligning film are obtained.
- the diamine of the present invention when used as a raw material for a polymer constituting a liquid crystal alignment film, it has high film strength, suppresses AC afterimages, and can be used even after being exposed to high temperatures for a long time. It is also possible to provide a liquid crystal aligning agent capable of obtaining a liquid crystal aligning film having a high voltage holding rate, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and a liquid crystal display element using the same.
- halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like.
- Boc represents a tert-butoxycarbonyl group, and "*" represents the bonding position.
- the diamine of the present invention is a diamine (0) (also referred to as a specific diamine in the present invention) represented by any of the following formulas (d A -1) to (d A -6).
- the method for producing the specific diamine of the present invention is not particularly limited, but preferred methods include a production method including the following steps (i) to (iv).
- Step (i)> A diamine represented by the following formula (d i -1) is reacted with an amino protection reagent such as di-tert-butyl dicarbonate to obtain a compound (d i -2) in which the amino group is protected with a Boc group.
- Y in formula (i) represents a divalent organic group obtained by removing two amino groups from diamine, and the diamine is 4,4'-diaminodiphenylamine or 4,4'-diaminodiphenyl-N -Methylamine.
- ⁇ Step (ii)> A compound represented by the formula (d i -2) is reacted with a tetracarboxylic dianhydride to obtain a compound represented by the following formula (d i -3).
- X in formula (ii) represents a tetravalent organic group obtained by removing two acid anhydride groups from tetracarboxylic dianhydride
- examples of the tetracarboxylic dianhydride include pyromellitic dianhydride
- Examples include 3,3',4,4'-benzophenonetetracarboxylic dianhydride and 3,3',4,4'-biphenyltetracarboxylic dianhydride.
- Y in formula (ii) has the same meaning as formula (i).
- Step (iii)> The compound represented by the above formula (d i -3) is imidized to obtain a diimide compound (di-4) in which the amino group is protected with a Boc group.
- Step (iv)> The above compound (di-4) is reacted with an inorganic acid such as hydrochloric acid to perform a deprotection reaction to obtain the diamine compound of the present invention.
- the reaction temperature is not particularly limited, but the reaction may be carried out at 0 to 100°C.
- a solvent can be used in the synthesis reaction of the specific diamine, if necessary.
- the above-mentioned solvent is not particularly limited as long as it can dissolve the compound.
- Specific examples include water or alcohols such as methanol, ethanol, propanol, and butanol; ethers such as diethyl ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; esters such as ethyl acetate;
- Other examples include organic solvents such as N,N-dimethylsulfoxide, dimethylformamide, dimethylacetamide, and N-methyl-2-pyrrolidone, which can be used as appropriate depending on the type of reaction.
- a method for imidizing the above step (iii) a method of thermal imidization in which the solution of the compound represented by the formula (d i -3) is directly heated, or a method of thermal imidization of the compound represented by the formula (d i -3)
- Examples include a method of catalytic imidization in which a catalyst is added to a solution of , and the method of catalytic imidization is preferred from the viewpoint of easy synthesis.
- a basic catalyst and an acid anhydride are added to a solution of the compound represented by formula (d i -3), and the reaction is carried out preferably at 0 to 120°C, more preferably at 0 to 100°C.
- the amount of the basic catalyst is preferably 0.5 to 30 moles, more preferably 2 to 20 moles, of the amic acid group possessed by the compound represented by formula (d i -3).
- the amount of acid anhydride is preferably 1 to 50 moles, more preferably 1 to 30 moles, of the amic acid group possessed by the compound represented by formula (d i -3).
- the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc. Among them, pyridine is preferred because it has an appropriate basicity to advance the reaction.
- the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is preferably used because it facilitates purification after the reaction is completed.
- the diamine of the present invention can be used as a raw material for a polymer constituting a liquid crystal alignment film.
- a polymer for example, a polyimide precursor obtained using a diamine component containing a diamine (0) represented by any one of formulas (d A -1) to (d A -6), and a polyimide precursor of the polyimide precursor.
- At least one kind of polymer (P) selected from the group consisting of imidized polyimides is mentioned.
- the polymer (P) of the present invention is a polyimide precursor obtained using a diamine component containing the above diamine (0), or a polyimide that is an imidized product of the polyimide precursor.
- the polyimide precursor is a polymer that can be imidized to obtain polyimide, such as polyamic acid or polyamic acid ester.
- Polyamic acid (P') which is the polyimide precursor of the polymer (P), can be obtained by a polymerization reaction between a diamine component containing the diamine (0) and a tetracarboxylic acid component.
- the above diamine (0) may be used alone or in combination of two or more.
- the amount of diamine (0) used is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, based on the total diamine components.
- the diamine component used in the production of the polyamic acid (P') may contain diamines other than diamine (0) (hereinafter also referred to as other diamines).
- diamine (0) hereinafter also referred to as other diamines.
- the amount of diamine (0) used relative to the diamine component is preferably 90 mol% or less, more preferably 80 mol% or less.
- diamines examples include other diamines listed below, but the invention is not limited thereto.
- the other diamines mentioned above may be used alone or in combination of two or more.
- At least one nitrogen atom-containing structure (hereinafter also referred to as a specific nitrogen atom-containing structure). ) (However, the molecule does not have an amino group bonded to a protecting group that is removed by heating and replaced by a hydrogen atom.); 2,4-diaminophenol, 3,5-diaminophenol, 3,5- Diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diamino-3,3'-dihydroxybiphenyl; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid acid, 4,4'-d
- Represents a divalent organic group formed by inserting at least one of -O- and -OC( O)-.Even if any hydrogen atom of A is substituted with a halogen atom, good.
- One or more hydrogen atoms on the benzene ring, biphenyl structure, or naphthalene ring may be substituted with a monovalent group, and examples of the monovalent group include a halogen atom, an alkyl group having 1 to 3 carbon atoms, Alkenyl group having 2 to 3 carbon atoms, alkoxy group having 1 to 3 carbon atoms, fluoroalkyl group having 1 to 3 carbon atoms, fluoroalkenyl group having 2 to 3 carbon atoms, fluoroalkoxy group having 1 to 3 carbon atoms, carbon number Examples include 2-3 alkyloxycarbonyl groups, cyano groups, nitro groups, and the like. ) (In formula (d AL -6), the sum of m1, m2 and n is 3 to 12. In formula (d AL -8), the sum of m1, m2 and n is 3 to 12.)
- m and n are each independently an integer of 0 to 3, satisfying 1 ⁇ m+n ⁇ 4.
- j is an integer of 0 or 1.
- X 1 is -(CH 2 ) a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH 3 )-, -NH-, -O-, Represents -CH 2 O-, -CH 2 -OCO-, -COO-, or -OCO-.
- R 1 is a fluorine atom, a fluorine atom-containing alkyl group having 1 to 10 carbon atoms, a fluorine atom-containing alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and Represents a monovalent group such as an alkoxyalkyl group having 2 to 10 carbon atoms.
- X 2 represents -O-, -CH 2 O-, -CH 2 -OCO-, -COO-, or -OCO-.
- the amount of the other diamines used is preferably 10 to 90 mol%, more preferably 20 to 90 mol%, based on the total diamine components used. It is 80 mol%.
- the above-mentioned other diamines can be used in various ways depending on the purpose, but for example, from the viewpoint of improving voltage holding characteristics when used as a liquid crystal alignment film, there are urea bonds, amide bonds, carboxyl groups, and hydroxy groups in the molecule.
- the tetracarboxylic acid component to be reacted with the diamine component is not only tetracarboxylic dianhydride, but also tetracarboxylic acid, tetracarboxylic acid dihalide, tetracarboxylic acid dialkyl ester, or tetracarboxylic acid dianhydride.
- tetracarboxylic dianhydrides such as carboxylic dialkyl ester dihalides can also be used.
- tetracarboxylic dianhydride or its derivative examples include acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, or derivatives thereof. .
- the acyclic aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure.
- Alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to an alicyclic structure. However, none of these four carboxy groups is bonded to an aromatic ring.
- Aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to an aromatic ring.
- Aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups including at least one carboxy group bonded to an aromatic ring.
- tetracarboxylic acid component that can be used in the production of the polyamic acid (P')
- the following tetracarboxylic dianhydrides or derivatives thereof are collectively referred to as specific tetracarboxylic acid (also called derivatives).
- Acyclic aliphatic tetracarboxylic dianhydride such as 1,2,3,4-butanetetracarboxylic dianhydride; 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl -1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3 , 4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-difluoro-1,2,3, 4-Cyclobutanetetracarboxylic dianhydride, 1,3-bis(trifluoromethyl)-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracar
- Preferred examples of the specific tetracarboxylic acid derivatives include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl -1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl- 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-difluoro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-bis(trifluoromethyl)-1 , 2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3, 3'
- the proportion of the specific tetracarboxylic acid derivative used is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 50 mol% or more, based on the total tetracarboxylic acid component used.
- the liquid crystal aligning agent of the present invention is a liquid composition in which the polymer (P) and other components used as necessary are preferably dispersed or dissolved in a suitable solvent.
- the total content of the polymers contained in the liquid crystal aligning agent of the present invention can be changed as appropriate depending on the thickness of the coating film to be formed, but from the viewpoint of forming a uniform and defect-free coating film, the total content is 1 mass. % or more, and from the viewpoint of storage stability of the solution, 10% by mass or less is preferable.
- a particularly preferred total polymer content is 2 to 8% by weight.
- the content of the polymer (P) used in the present invention is preferably 1 to 100% by mass, more preferably 10 to 100% by mass, and 20 to 100% by mass based on the total amount of polymers contained in the liquid crystal aligning agent. % is particularly preferred.
- the liquid crystal aligning agent of the present invention may contain other polymers than the polymer (P).
- other polymers include, in addition to the above polymer (P), a polyimide precursor obtained using a diamine component that does not contain the above specific diamine, and a polyimide that is an imidized product of the polyimide precursor.
- Examples include polymers selected from the group.
- poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), GSM301 (manufactured by Gifu Cerac Manufacturing Co., Ltd.), and poly(isobutylene-maleic anhydride) copolymers include A specific example of the anhydride copolymer is Isoban-600 (manufactured by Kuraray Co., Ltd.).
- a specific example of the poly(vinyl ether-maleic anhydride) copolymer includes Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland Corporation).
- polymer (B) is more preferred from the viewpoint of maintaining voltage holding rate and reducing afterimages derived from residual DC.
- the other polymers mentioned above may be used alone or in combination of two or more.
- the content ratio of other polymers is preferably 90 parts by mass or less, more preferably 10 to 90 parts by mass, and further 20 to 80 parts by mass with respect to the total 100 parts by mass of the polymers contained in the liquid crystal aligning agent. preferable.
- the tetracarboxylic acid component used in the production of the polymer (B) include the same compounds as those exemplified for the polymer (P), including preferred specific examples.
- the tetracarboxylic acid component used for producing the polymer (B) is more preferably a tetracarboxylic dianhydride having at least one partial structure selected from the group consisting of a benzene ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring.
- the tetracarboxylic acid component used in the production of the polymer (B) is an acyclic aliphatic tetracarboxylic dianhydride, an alicyclic tetracarboxylic dianhydride, or these. Derivatives of are preferred.
- the amount of the specific tetracarboxylic acid derivative used is preferably 10 mol% or more, more preferably 20 mol% or more, and 50 mol% or more, based on the total tetracarboxylic acid components used for producing the polymer (B). More preferably mol% or more.
- Examples of the diamine component for obtaining the polymer (B) include the diamines exemplified for the polymer (P) above.
- the diamine components for obtaining the polymer (B) from the viewpoint of improving liquid crystal orientation, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl- p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 2,2'- Difluoro-4,4'-
- diamine represented by the above formula (d AL ) include diamines represented by the above formulas (d AL -1) to (d AL -10), 1,7-bis(4-aminophenoxy)heptane, , 1,7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, 1,9-bis(4-aminophenoxy) ) nonane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis(4-aminophenoxy)decane, 1,10-bis(3-aminophenoxy)decane, 1,11-bis(4- aminophenoxy)undecane, 1,11-bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-amin
- the diamine component one type of diamine may be used alone, or two or more types may be used in combination.
- the amount used is preferably 10 mol% or more, more preferably 20 mol% or more, based on the total diamine components used for producing the polymer (B).
- the amount used is preferably 90 mol% or less, more preferably 80 mol% or less of the total diamine components used for producing the polymer (B).
- Polyamic acid is produced by reacting a diamine component and a tetracarboxylic acid component in an organic solvent.
- the ratio of the tetracarboxylic acid component and diamine component used in the polyamic acid production reaction is such that the acid anhydride group of the tetracarboxylic acid component is 0.5 to 2 equivalents per 1 equivalent of the amino group of the diamine component.
- the ratio is preferably 0.8 to 1.2 equivalents, and more preferably 0.8 to 1.2 equivalents.
- the closer the equivalent of the acid anhydride group of the tetracarboxylic acid component is to 1 equivalent the larger the molecular weight of the polyamic acid produced becomes.
- the reaction temperature in the production of polyamic acid is preferably -20 to 150°C, more preferably 0 to 100°C. Further, the reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours. Polyamic acid can be produced at any concentration, but the concentration of polyamic acid is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. It is also possible to carry out the reaction at a high concentration in the initial stage and then add a solvent.
- organic solvents include cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, ⁇ -butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl
- examples include sulfoxide and 1,3-dimethyl-2-imidazolidinone.
- the polymer has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene Solvents such as glycol monopropyl ether, diethylene glycol monomethyl ether, or diethylene glycol monoethyl ether can be used.
- Polyamic acid esters can be produced by, for example, [I] a method of reacting the polyamic acid obtained by the above method with an esterifying agent, [II] a method of reacting a tetracarboxylic acid diester with a diamine, [III] a method of reacting a tetracarboxylic acid diester with a diamine, and [III] a method of reacting a tetracarboxylic acid diester with a diamine. It can be obtained by a known method such as a method of reacting a diester dihalide with a diamine.
- Polyimide can be obtained by ring-closing (imidizing) a polyimide precursor such as the above polyamic acid or polyamic acid ester.
- the imidization ratio as used herein refers to the ratio of imide groups to the total amount of imide groups and carboxy groups (or derivatives thereof) derived from tetracarboxylic dianhydride or its derivatives.
- the imidization rate does not necessarily have to be 100%, and can be arbitrarily adjusted depending on the use and purpose.
- Examples of methods for imidizing the polyimide precursor include thermal imidization, in which the polyimide precursor solution is directly heated, and catalytic imidization, in which a catalyst is added to the polyimide precursor solution.
- the temperature when thermally imidizing the polyimide precursor in a solution is preferably 100 to 400°C, more preferably 120 to 250°C, and it is preferable to perform the thermal imidization while removing water generated by the imidization reaction from the system. is preferred.
- Catalytic imidization of the polyimide precursor is carried out by adding a basic catalyst and an acid anhydride to a solution of the polyimide precursor, and stirring the mixture preferably at -20 to 250°C, more preferably at 0 to 180°C. I can do it.
- the amount of the basic catalyst is preferably 0.5 to 30 times the amount of the amic acid group, more preferably 2 to 20 times the amount, and the amount of the acid anhydride is preferably 1 to 50 times the amount of the amic acid group. Preferably it is 3 to 30 times the mole.
- the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc.
- pyridine is preferred because it has an appropriate basicity to allow the reaction to proceed.
- the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride.
- acetic anhydride is preferably used because it facilitates purification after the reaction is completed.
- the imidization rate by catalytic imidization can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.
- the reaction solution may be poured into a solvent and precipitated.
- the solvent used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, water, and the like.
- the polymer precipitated in a solvent can be collected by filtration and then dried under normal pressure or reduced pressure, at room temperature or by heating.
- the amount of impurities in the polymer can be reduced.
- the solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more types of solvents selected from these, since the efficiency of purification will further increase.
- the ends are capped using an appropriate end-capping agent together with a tetracarboxylic acid component containing tetracarboxylic dianhydride or its derivative, and a diamine component containing the above-mentioned diamine.
- Types of polymers may also be produced.
- the end-capped polymer has the effect of improving the film hardness of the alignment film obtained by coating and improving the adhesion characteristics between the sealant and the alignment film.
- the terminals of the polyimide precursor and polyimide in the present invention include amino groups, carboxy groups, acid anhydride groups, and groups derived from the terminal capping agent described below.
- the amino group, carboxy group, and acid anhydride group can be obtained by a conventional condensation reaction or by capping the terminal using the terminal capping agent shown below.
- terminal capping agent examples include acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, 1,2-cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, and trimellitic anhydride.
- Examples include isocyanates having unsaturated bonds.
- the proportion of the terminal capping agent used is preferably 0.01 to 20 parts by mole, more preferably 0.01 to 10 parts by mole, based on a total of 100 parts by mole of the diamine component used.
- the weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of the polyimide precursor and polyimide is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. It is. Further, the molecular weight distribution (Mw/Mn) expressed as the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 15 or less, more preferably 10 or less. By having a molecular weight within this range, good alignment of the liquid crystal display element can be ensured.
- the organic solvent contained in the liquid crystal aligning agent according to the present invention is not particularly limited as long as it can uniformly dissolve the polymer (P) and other polymers added as necessary.
- P polymer
- N-ethyl-2-pyrrolidone dimethyl sulfoxide, ⁇ -butyrolactone, ⁇ -valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethyl Propanamide, 3-butoxy-N,N-dimethylpropanamide, N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-( tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, N- Examples include cyclol
- N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide or ⁇ -butyrolactone are preferred.
- the content of the good solvent is preferably 20 to 99% by mass, more preferably 20 to 90% by mass, and particularly preferably 30 to 80% by mass of the total solvent contained in the liquid crystal aligning agent.
- the organic solvent contained in the liquid crystal aligning agent is a mixture of the above solvents and a solvent (also referred to as a poor solvent) that improves the coating properties and surface smoothness of the coating film when applying the liquid crystal aligning agent. Preference is given to using a solvent. Specific examples of poor solvents are shown below, but are not limited thereto.
- the content of the poor solvent is preferably 1 to 80% by mass, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass of the total solvent contained in the liquid crystal aligning agent.
- the type and content of the poor solvent are appropriately selected depending on the liquid crystal aligning agent coating device, coating conditions, coating environment, and the like.
- the poor solvent examples include diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-dibutoxyethane, Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethyl butyl acetate, 2 - Ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl
- diisobutyl carbinol propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene Glycol monobutyl ether acetate or diisobutyl ketone is preferred.
- Preferred solvent combinations of good and poor solvents include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, ⁇ -butyrolactone and ethylene glycol monobutyl ether, and N-methyl-2-pyrrolidone and ⁇ -butyrolactone and ethylene glycol monobutyl ether.
- the liquid crystal aligning agent of the present invention may contain other components (hereinafter also referred to as additive components) in addition to the above polymer (P), the above other polymers, and the above organic solvent.
- additive components include, for example, a crosslinkable compound (c-1) having at least one substituent selected from an oxiranyl group, an oxetanyl group, a blocked isocyanate group, an oxazoline group, a cyclocarbonate group, a hydroxy group, and an alkoxy group.
- crosslinkable compound selected from the group consisting of a crosslinkable compound (c-2) having a polymerizable unsaturated group, a functional silane compound, a metal chelate compound, a curing accelerator, a surfactant, and an antioxidant.
- crosslinkable compounds (c-1) and (c-2) include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether.
- Glycidyl ether neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol , bisphenol A type epoxy resins such as Epicote 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins such as Epicote 807 (manufactured by Mitsubishi Chemical Corporation), and hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation).
- biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolak type epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p-) Cresol novolak type epoxy resin, triglycidyl isocyanurate such as TEPIC (manufactured by Nissan Chemical Co., Ltd.), alicyclic epoxy resin such as Celoxide 2021P (manufactured by Daicel Corporation), N, N, N', N'- Tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, or N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane.
- YX6954BH30 manufactured by Mitsubishi Chemical Corporation
- a compound containing a tertiary nitrogen atom a compound having two or more oxiranyl groups such as tetrakis(glycidyloxymethyl)methane;
- Compounds having two or more oxetanyl groups Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (manufactured by Tosoh Corporation), Takenate B-830, B-815N, B-820NSU , B-842N, B-846N, B-870N, B-874N, B-882N (manufactured by Mitsui Chemicals, Inc.) and other compounds having blocked isocyanate groups; 2,2'-bis(2-oxazoline), 2 , 2'-bis(4-methyl-2-oxazoline), 2,2'-bis(5-methyl-2-oxazoline), 1,2,4-tris(2-oxazolinyl)-benzene, Epocross (Nippon Sho
- the content of the crosslinkable compounds (c-1) and (c-2) contained in the liquid crystal aligning agent of the present invention is from 0.1 to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.
- the amount is preferably 30 parts by weight, more preferably 0.1 to 20 parts by weight, and still more preferably 5 to 20 parts by weight.
- Examples of compounds for adjusting the dielectric constant and electrical resistance include monoamines having a nitrogen atom-containing aromatic heterocycle such as 3-picolylamine.
- the content of the monoamine having a nitrogen atom-containing aromatic heterocycle is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, based on 100 parts by mass of the polymer component contained in the liquid crystal aligning agent. Part by mass.
- Preferred specific examples of the functional silane compounds include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, and 2-aminopropyltrimethoxysilane.
- the compounds for promoting imidization include basic moieties (e.g., primary amino groups, aliphatic heterocycles (e.g., pyrrolidine skeleton), aromatic heterocycles (e.g., imidazole ring, indole ring), or guanidino group, etc.) (however, the above-mentioned crosslinkable compounds and adhesion aids are excluded), or compounds in which the above-mentioned basic moieties are generated during firing are preferred. More preferably, it is a compound in which the above-mentioned basic site is generated during calcination, and specific preferred examples include amino acids in which part or all of the basic site of the amino acid is protected.
- basic moieties e.g., primary amino groups, aliphatic heterocycles (e.g., pyrrolidine skeleton), aromatic heterocycles (e.g., imidazole ring, indole ring), or guanidino group, etc.) (however, the above
- Examples of the protecting group for the basic site of the amino acid include carbamate-based protecting groups such as Boc group.
- Specific examples of the above amino acids include glycine, alanine, cysteine, methionine, asparagine, glutamine, valine, leucine, phenylalanine, tyrosine, tryptophan, proline, hydroxyproline, arginine, histidine, lysine, and ornithine.
- a more preferable example of the compound for promoting imidization is N- ⁇ -(9-fluorenylmethoxycarbonyl)-N- ⁇ -(tert-butoxycarbonyl)-L-histidine.
- the content of the compound for promoting imidization contained in the liquid crystal aligning agent of the present invention is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, More preferably 0.1 to 20 parts by weight, still more preferably 5 to 20 parts by weight.
- the solid content concentration in the liquid crystal aligning agent (the ratio of the total mass of components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., but is preferably It is 1 to 10% by mass.
- the particularly preferable solid content concentration range varies depending on the method used when applying the liquid crystal aligning agent to the substrate. For example, when using a spin coating method, it is particularly preferable that the solid content concentration is 1.5 to 4.5% by mass. When the printing method is used, it is particularly preferable that the solid content concentration is 3 to 9% by mass, and thereby the solution viscosity is 12 to 50 mPa ⁇ s.
- the solid content concentration be 1 to 5% by mass and the solution viscosity be 3 to 15 mPa ⁇ s.
- the temperature when preparing the polymer composition is preferably 10 to 50°C, more preferably 20 to 30°C.
- the liquid crystal display element according to the present invention includes a liquid crystal alignment film formed using the above liquid crystal alignment agent.
- the operation mode of the liquid crystal display element is not particularly limited, and includes, for example, TN type, STN type, vertical alignment type (including VA-MVA type, VA-PVA type, etc.), and in-plane switching type (IPS type, FFS type). , optically compensated bend type (OCB type), and various other operation modes.
- the liquid crystal display element of the present invention can be produced, for example, by a method including the following steps (1) to (4), a method including steps (1) to (2) and (4), and a method including steps (1) to (3), ( It can be produced by a method including steps 4-2) and (4-4), or a method including steps (1) to (3), (4-3) and (4-4).
- Step (1) is a step of applying a liquid crystal aligning agent onto the substrate.
- a specific example of step (1) is as follows.
- a liquid crystal aligning agent is applied onto one surface of the substrate provided with the patterned transparent conductive film by an appropriate coating method such as a roll coater method, a spin coat method, a printing method, an inkjet method, or the like.
- the material of the substrate is not particularly limited as long as it is a highly transparent substrate, and in addition to glass and silicon nitride, plastics such as acrylic and polycarbonate can also be used.
- an opaque material such as a silicon wafer can be used as long as only one substrate is used, and in this case, a material that reflects light such as aluminum can also be used for the electrodes.
- a substrate is provided with an electrode made of a transparent conductive film or a metal film patterned in a comb-like shape, and a counter substrate is not provided with an electrode. and use.
- An IPS substrate which is a comb-teeth electrode substrate used in an IPS type liquid crystal display element, includes, for example, a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-teeth shape, and a plurality of linear electrodes formed on the base material. and a liquid crystal alignment film formed to cover the linear electrodes.
- the FFS substrate which is a comb-teeth electrode substrate used in an FFS type liquid crystal display element, includes, for example, a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, It has a plurality of linear electrodes formed on an insulating film and arranged in a comb-like shape, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.
- Examples of methods for applying the liquid crystal aligning agent to the substrate to form a film include screen printing, offset printing, flexographic printing, an inkjet method, and a spray method. Among these, coating and film forming methods using an inkjet method can be suitably used.
- Step (2) is a step of baking the liquid crystal alignment agent applied onto the substrate to form a film.
- a specific example of step (2) is as follows. After applying the liquid crystal aligning agent onto the substrate in step (1), the solvent is evaporated or the polyamic acid is thermally imidized using a heating means such as a hot plate, a hot air circulation type oven, or an IR (infrared) type oven. You can go there.
- the drying and baking steps after applying the liquid crystal aligning agent can be performed at any temperature and time, and may be performed multiple times.
- the temperature at which the liquid crystal aligning agent is fired can be, for example, 40 to 180°C.
- the firing time is not particularly limited, but examples include 1 to 10 minutes or 1 to 5 minutes.
- a step of firing at, for example, 150 to 300° C. or 150 to 250° C. may be added after the above steps.
- the firing time is not particularly limited, but examples include a firing time of 5 to 40 minutes or 5 to 30 minutes.
- the thickness of the film-like material after firing is preferably 5 to 300 nm, more preferably 10 to 200 nm, since reliability of the liquid crystal display element may decrease if it is too thin.
- Step (3) is a step of subjecting the film obtained in step (2) to an orientation treatment, depending on the case. That is, in a horizontal alignment type liquid crystal display element such as an IPS system or an FFS system, the coating film is subjected to an alignment ability imparting treatment. On the other hand, in a vertical alignment type liquid crystal display element such as VA mode or PSA mode, the formed coating film can be used as a liquid crystal alignment film as it is, but the coating film may be subjected to alignment ability imparting treatment. Examples of the alignment treatment method for the liquid crystal alignment film include a rubbing alignment treatment method and a photo alignment treatment method.
- the surface of the film-like material is irradiated with radiation polarized in a certain direction, and in some cases, heat treatment is preferably performed at a temperature of 150 to 250°C to improve liquid crystal alignment (liquid crystal alignment).
- heat treatment is preferably performed at a temperature of 150 to 250°C to improve liquid crystal alignment (liquid crystal alignment).
- One example is the method of imparting the ability (also called Noh).
- the radiation ultraviolet rays or visible light having a wavelength of 100 to 800 nm can be used. Among these, ultraviolet light having a wavelength of preferably 100 to 400 nm, more preferably 200 to 400 nm.
- the radiation dose is preferably 1 to 10,000 mJ/cm 2 , more preferably 100 to 5,000 mJ/cm 2 .
- the substrate having the film-like material may be irradiated while being heated at 50 to 250° C. in order to improve liquid crystal alignment.
- the liquid crystal alignment film produced in this way can stably align liquid crystal molecules in a certain direction.
- a coating film irradiated with polarized radiation or a coating film subjected to a rubbing alignment treatment in the above method may be subjected to a contact treatment using water or a solvent.
- the film subjected to the above-mentioned orientation treatment may be subjected to heat treatment without being subjected to contact treatment.
- the film subjected to the above contact treatment may be further subjected to heat treatment.
- the solvent used in the above-mentioned contact treatment is not particularly limited as long as it dissolves the decomposed product produced from the film-like material by radiation irradiation.
- Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, 3- Examples include methyl methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate.
- the number of solvents may be one or a combination of two or more.
- the temperature for heat treatment of the coating film irradiated with the above radiation is more preferably 50 to 300°C, and even more preferably 120 to 250°C.
- the time for each heat treatment is preferably 1 to 30 minutes.
- Step (4) Step of producing a liquid crystal cell> Two substrates each having a liquid crystal alignment film formed thereon as described above are prepared, and a liquid crystal is placed between the two substrates which are placed facing each other. Specifically, the following two methods can be mentioned. In the first method, first, two substrates are placed facing each other with a gap (cell gap) in between so that the respective liquid crystal alignment films face each other. Next, the peripheral parts of the two substrates are bonded together using a sealant, and a liquid crystal composition is injected and filled into the cell gap defined by the substrate surface and the sealant to contact the film surface, and then the injection hole is sealed. Stop.
- the second method is a technique called ODF (One Drop Fill) method.
- ODF One Drop Fill
- an ultraviolet light-curable sealant is applied to a predetermined location on one of the two substrates on which a liquid crystal alignment film has been formed, and a liquid crystal composition is further applied to several predetermined locations on the surface of the liquid crystal alignment film. drip.
- the other substrate is bonded together so that the liquid crystal alignment films face each other, and the liquid crystal composition is spread over the entire surface of the substrate and brought into contact with the film surface.
- the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant.
- the two substrates are arranged facing each other so that the rubbing directions of each coating film are at a predetermined angle, for example, perpendicular or antiparallel to each other.
- the sealant for example, an epoxy resin containing a hardening agent and aluminum oxide spheres as a spacer can be used.
- the liquid crystal composition is not particularly limited, and includes a composition containing at least one kind of liquid crystal compound (liquid crystal molecule) and exhibiting a nematic phase (hereinafter also referred to as nematic liquid crystal), a smectic phase.
- nematic liquid crystal liquid crystal
- examples include liquid crystals and liquid crystal compositions exhibiting a cholesteric phase, among which nematic liquid crystals are preferred.
- various liquid crystal compositions having positive or negative dielectric anisotropy can be used. Note that, hereinafter, a liquid crystal composition having a positive dielectric anisotropy is also referred to as a positive type liquid crystal, and a liquid crystal composition having a negative dielectric anisotropy is also referred to as a negative type liquid crystal.
- the liquid crystal composition may include a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (for example, a trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, It may contain a liquid crystal compound having a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, and a compound having two or more rigid sites (mesogen skeletons) that exhibit liquid crystallinity within the molecule (for example, two rigid biphenyl structure, or a bimesogenic compound in which a terphenyl structure is linked with an alkyl group).
- a fluorine atom for example, a trifluoromethyl group
- a cyano group for example, an alkyl group, an alkoxy group,
- the above-mentioned liquid crystal composition may further contain an additive from the viewpoint of improving liquid crystal alignment.
- additives include photopolymerizable monomers such as compounds having polymerizable groups; optically active compounds (e.g. S-811 manufactured by Merck & Co., Ltd.); antioxidants; ultraviolet absorbers; pigments; Examples include antifoaming agents; polymerization initiators; and polymerization inhibitors.
- Examples of the positive liquid crystal include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, and MLC-7081 manufactured by Merck & Co., Ltd.
- Examples of the negative type liquid crystal include MLC-6608, MLC-6609, MLC-6610, MLC-7026, and MLC-7026-100 manufactured by Merck. Further, as a liquid crystal containing a compound having a polymerizable group, MLC-3023 manufactured by Merck & Co., Ltd. can be mentioned.
- the liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and has a liquid crystal composition containing a polymerizable compound that is polymerized by at least one of active energy rays and heat between the pair of substrates.
- a liquid crystal display element (PSA type liquid crystal display element) manufactured through a process of arranging objects and polymerizing a polymerizable compound by at least one of active energy ray irradiation and heating while applying a voltage between electrodes.
- PSA type liquid crystal display element manufactured through a process of arranging objects and polymerizing a polymerizable compound by at least one of active energy ray irradiation and heating while applying a voltage between electrodes.
- the liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and a polymerizable group that is polymerized by at least one of active energy rays and heat is provided between the pair of substrates. It is also preferably used for a liquid crystal display element (SC-PVA mode liquid crystal display element) manufactured through a process of arranging a liquid crystal alignment film containing the present invention and applying a voltage between electrodes.
- SC-PVA mode liquid crystal display element manufactured through a process of arranging a liquid crystal alignment film containing the present invention and applying a voltage between electrodes.
- Step (4-2) In case of PSA type liquid crystal display element> It is carried out in the same manner as in (4) above, except that the liquid crystal composition containing the polymerizable compound is injected or dropped.
- the polymerizable compound include polymerizable compounds having one or more polymerizable unsaturated groups such as acrylate groups and methacrylate groups in the molecule.
- ⁇ Step (4-3) In case of SC-PVA mode type liquid crystal display element> A method may be adopted in which a liquid crystal display element is manufactured by performing the same process as in (4) above and then performing a step of irradiating ultraviolet rays, which will be described later. According to this method, a liquid crystal display element with excellent response speed can be obtained with a small amount of light irradiation, as in the case of manufacturing the above-mentioned PSA type liquid crystal display element.
- the compound having a polymerizable group may be a compound having one or more of the above polymerizable unsaturated groups in the molecule, and the content thereof is 0.1 to 30 parts by mass based on 100 parts by mass of all polymer components.
- the above-mentioned polymerizable group may be included in the polymer used for the liquid crystal alignment agent, and examples of such a polymer include, for example, a diamine component containing a diamine having the above-mentioned photopolymerizable group at the end. Examples include the resulting polymers.
- Step (4-4) Step of irradiating ultraviolet rays>
- the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates obtained in (4-2) or (4-3) above.
- the voltage applied here can be, for example, 5 to 50 V direct current or alternating current.
- the light to be irradiated for example, ultraviolet rays and visible light including light with a wavelength of 150 to 800 nm can be used, but ultraviolet rays including light with a wavelength of 300 to 400 nm are preferable.
- a light source for the irradiation light for example, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, etc. can be used.
- the amount of light irradiation is preferably 1,000 to 200,000 J/m 2 , more preferably 1,000 to 100,000 J/m 2 .
- a liquid crystal display element can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell, if necessary.
- the polarizing plate bonded to the outer surface of the liquid crystal cell is a polarizing plate in which a polarizing film called "H film” made by stretching and aligning polyvinyl alcohol and absorbing iodine is sandwiched between cellulose acetate protective films, or the H film itself.
- a polarizing plate consisting of:
- CA-1 to CA-6 Compounds represented by the following formulas (CA-1) to (CA-6), respectively
- DA-W1 to DA-W6 Compounds represented by the following formulas (DA-W1) to (DA-W6), respectively (compounds represented by the following formulas (DA-W1) to (DA-W6) are , are the same as the diamines represented by the above formulas (d A -1) to (d A -6).)
- AD-1 to AD-3 Compounds represented by the following formulas (AD-1) to (AD-3), respectively
- Measurement of viscosity was performed using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), a sample volume of 1.1 mL, and a cone rotor TE-1 (1° 34', R24) at a temperature of 25°C.
- GPC device SSC-7200 (manufactured by Senshu Kagaku), column: GPC KD-803, GPC KD-805 (manufactured by Showa Denko) in series, column temperature: 50°C, eluent: N,N-dimethylformamide (added)
- LiBr.H2O lithium bromide monohydrate
- o-phosphoric acid phosphoric acid/anhydrous crystal
- THF tetrahydrofuran
- TSK standard polyethylene oxide molecular weight: approx. 900,000, 150,000, 100,000 and 30,000
- polyethylene glycol molecular weight: approx. 12,000, 4,000 and 1,000
- [DA-W6-1] (16.1g, 17.6mmol), 12N hydrochloric acid (29.7g), and AcOEt (320g) were added to a 3L four-neck flask, and the mixture was stirred at 70°C to react. Ta. After the reaction was completed, the precipitate was separated by filtration, MeCN (700 g) was added to the obtained crude material, neutralized using triethylamine until it became basic, and the precipitate was separated by filtration. NMP (60 g) was added to the obtained crude material to completely dissolve it, and then poured into MeCN (360 g).
- DA-W1 (2.15 g, 3.28 mmol), DA-4 (0.734 g, 2.46 mmol), DA-8 (1.04 g, 2.46 mmol) and NMP (35.3 g) were added and dissolved by stirring at room temperature while supplying nitrogen. Then, by adding CA-1 (1.42 g, 7.23 mmol) and NMP (3.86 g) and stirring at room temperature for 2 hours, a solution of polyamic acid (PAA-A2) with a solid content concentration of 12% by mass was prepared. (Viscosity: 402 mPa ⁇ s) was obtained.
- PAA-A2 polyamic acid
- Example 2-3 Add DA-W1 (2.99 g, 4.55 mmol), DA-4 (0.731 g, 2.45 mmol) and NMP (27.3 g) to a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred and dissolved at room temperature while supplying nitrogen. Then, CA-1 (0.153 g, 0.781 mmol) and NMP (1.13 g) were added and stirred at room temperature for 1 hour.
- Example 2-4 Add DA-W2 (2.67 g, 3.90 mmol), DA-4 (0.627 g, 2.10 mmol) and NMP (30.1 g) to a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred and dissolved at room temperature while supplying nitrogen. Then, by adding CA-1 (1.06 g, 5.40 mmol) and NMP (2.26 g) and stirring at room temperature for 2 hours, a solution of polyamic acid (PAA-A4) with a solid content concentration of 12% by mass was prepared. (Viscosity: 411 mPa ⁇ s) was obtained.
- PAA-A4 polyamic acid
- DA-W2 (2.25 g, 3.28 mmol), DA-4 (0.734 g, 2.46 mmol), DA-8 (1.04 g, 2.46 mmol) and NMP (36.2 g) were added and dissolved by stirring at room temperature while supplying nitrogen. Then, by adding CA-1 (1.50 g, 7.67 mmol) and NMP (4.33 g) and stirring at room temperature for 2 hours, a solution of polyamic acid (PAA-A5) with a solid content concentration of 12% by mass was prepared. (Viscosity: 396 mPa ⁇ s) was obtained.
- Example 2-6 Add DA-W3 (1.89 g, 3.25 mmol), DA-4 (0.522 g, 1.75 mmol) and NMP (25.9 g) to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred and dissolved at room temperature while supplying nitrogen. Then, by adding CA-1 (0.804 g, 4.10 mmol) and NMP (2.99 g) and stirring at room temperature for 2 hours, a solution of polyamic acid (PAA-A6) with a solid content concentration of 10% by mass was prepared. (Viscosity: 237 mPa ⁇ s) was obtained.
- PAA-A6 polyamic acid
- Example 2-7 Add DA-W4 (2.37 g, 3.90 mmol), DA-4 (0.627 g, 2.10 mmol) and NMP (27.0 g) to a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred and dissolved at room temperature while supplying nitrogen. Then, by adding CA-1 (1.02 g, 5.22 mmol) and NMP (2.49 g) and stirring at room temperature for 2 hours, a solution of polyamic acid (PAA-A7) with a solid content concentration of 12% by mass was prepared. (Viscosity: 413 mPa ⁇ s) was obtained.
- DA-7 (3.79 g, 19.0 mmol), DA-4 (1.42 g, 4.76 mmol) and NMP (46.9 g) to a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred and dissolved at room temperature while supplying nitrogen. Then, CA-3 (2.80 g, 9.52 mmol) and NMP (11.9 g) were added and stirred at 70° C. for 4 hours.
- DA-7 (2.85 g, 14.3 mmol), DA-4 (1.42 g, 4.76 mmol), DA-8 (2.01 g, 4.76 mmol) and NMP (56.5 g) were added and dissolved by stirring at room temperature while supplying nitrogen. Then, CA-3 (2.80 g, 9.52 mmol) and NMP (10.1 g) were added and stirred at 70° C. for 4 hours. Then, by adding CA-1 (2.58 g, 13.2 mmol) and NMP (18.9 g) and stirring at room temperature for 2 hours, a solution of polyamic acid (PAA-B2) with a solid content concentration of 12% by mass was prepared. (Viscosity: 378 mPa ⁇ s) was obtained.
- PAA-B2 polyamic acid
- DA-1 (0.540 g, 4.99 mmol), DA-2 (1.83 g, 7.49 mmol), DA-3 (2.40 g, 7.49 mmol), DA-5 (1.99 g, 4.99 mmol), and NMP (68.4 g) were added and dissolved by stirring at room temperature while supplying nitrogen. Then, by adding CA-4 (5.31 g, 23.7 mmol) and NMP (20.1 g) and stirring at 50°C for 12 hours, polyamic acid (PAA-U1) with a solid content concentration of 12% by mass was prepared. A solution (viscosity: 402 mPa ⁇ s) was obtained.
- DA-1 (1.62 g, 15.0 mmol
- DA-2 (2.20 g, 9.01 mmol
- DA-6 (2.04 g, 5.97 mmol)
- NMP 59.3 g
- CA-4 6.32 g, 28.2 mmol
- NMP 30.0 g
- PAA-U2 polyamic acid
- DA-7 (4.78 g, 24.0 mmol), DA-4 (2.39 g, 8.01 mmol), DA-8 (3.37 g, 7.99 mmol) and NMP (77.3 g) were added and dissolved by stirring at room temperature while supplying nitrogen. Then, by adding CA-3 (11.3 g, 38.4 mmol) and NMP (82.9 g) and stirring at 70°C for 24 hours, polyamic acid (PAA-C1) with a solid content concentration of 12% by mass was prepared. A solution was obtained.
- PAA-C1 polyamic acid
- ⁇ Preparation example 2-4> Add DA-7 (2.55 g, 12.8 mmol), DA-9 (0.487 g, 3.20 mmol) and NMP (22.3 g) to a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube. The mixture was stirred and dissolved at room temperature while supplying nitrogen. Then, by adding CA-3 (4.50 g, 15.3 mmol) and NMP (20.5 g) and stirring at 50°C for 16 hours, polyamic acid (PAA-C2) with a solid concentration of 15% by mass was prepared. A solution (viscosity: 350 mPa ⁇ s) was obtained.
- PAA-C2 polyamic acid
- Table 1 shows the specifications of the polyamic acid obtained in the above synthesis example.
- the numbers in parentheses for the tetracarboxylic acid component and diamine component represent the amount (mol parts) of each tetracarboxylic acid component or each diamine used, based on the total amount of 100 mole parts of the diamine component used for polymerization. .
- the specific diamine DA-W1 has a structure obtained by reacting one molecule of tetracarboxylic dianhydride CA-3 with two molecules of diamine DA-7, and has a structure obtained by reacting one molecule of tetracarboxylic dianhydride CA-3 with two molecules of diamine DA-7.
- the synthesis of A1 corresponds to reacting using monomer components containing 4.98 mmol of CA-1, 3.90 mmol of CA-3, 7.80 mmol of DA-7, and 2.10 mmol of DA-4.
- the polyamic acid PAA-A1 of Example 2-1 is a polymer having an imide structure and the imide structures are present in adjacent positions
- the polyamic acid PAA-A1 of Comparative Example 2-1 B1 is a polymer having only an amic acid structure, and the obtained liquid crystal alignment film has different properties as described below.
- the polyamic acids PAA-A2 to PAA-A3 have substantially the same monomer composition as the polyamic acids PAA-B2 to PAA-B3, respectively.
- Example 3-1 Using the solution of polyamic acid (PAA-A1) obtained in Example 2-1, it was diluted with NMP, GBL, and BCS, and stirred at room temperature for 2 hours to adjust the mass ratio of the polymer solid content to each solvent.
- Examples 3-2 to 3-3 Comparative Examples 3-1 to 3-3> As shown in Table 2, carry out in the same manner as Example 3-1 except that the polyamic acid used was replaced with PAA-A2 to PAA-A3 and PAA-B1 to PAA-B3 from PAA-A1. Thus, liquid crystal alignment agents (AL-2) to (AL-3) and (AL-C1) to (AL-C3) were obtained.
- Example 3-4 Using the solution of polyamic acid (PAA-U1) obtained in Preparation Example 2-1 and the solution of polyamic acid (PAA-A1) obtained in Example 2-1, diluted with NMP, GBL and BCS. By stirring at room temperature for 2 hours, the solid content ratio of the polymer (PAA-U1:PAA-A1) was 5:5, and the mass ratio of the total solid content of the polymer to each solvent (polymer solid content: NMP: A liquid crystal aligning agent (AL-4) with GBL:BCS) of 5.5:44.5:30:20 was obtained.
- Example 3-7 Using the solution of polyamic acid (PAA-U1) obtained in Preparation Example 2-1 and the solution of polyamic acid (PAA-A1) obtained in Example 2-1, diluted with NMP, GBL and BCS. By further adding AD-1 and stirring at room temperature for 2 hours, the solid content ratio of the polymer (PAA-U1:PAA-A1) was 5:5, and the mass ratio of the total solid content of the polymer to each solvent ( Liquid crystal alignment in which the polymer solid content (NMP:GBL:BCS) is 5.5:44.5:30:20 and the blending ratio of AD-1 is 5 parts by mass with respect to 100 parts by mass of the total amount of polymer. Agent (AL-7) was obtained.
- Example 3-8 to 3-11 Comparative Example 3-4> As shown in Table 2, liquid crystal alignment was achieved by carrying out the same procedure as in Example 3-7, except that the polyamic acid used was replaced with PAA-A2 to PAA-A5, and PAA-C1 from PAA-A1. Agents (AL-8) to (AL-11) and (AL-C4) were obtained.
- the mass ratio (polymer solid content: NMP:GBL:BCS) is 5.5:44.5:30:20, and AD-1, AD-2, AD- Liquid crystal aligning agents (AL-C5) were obtained in which the blending ratios of 3 were 5 parts by mass, 1 part by mass, and 14 parts by mass, respectively.
- the numerical value in parentheses for polyamic acid represents the content (parts by mass) of each polyamic acid based on 100 parts by mass of the total amount of polymers contained in each liquid crystal aligning agent.
- the numerical value in parentheses for the additive represents the content (parts by mass) of each additive with respect to the total amount of 100 parts by mass of the polymer contained in each liquid crystal aligning agent.
- a liquid crystal cell having the structure of an FFS mode liquid crystal display element was manufactured.
- a substrate with electrodes was prepared.
- the substrate used was a glass substrate having a rectangular shape of 30 mm x 50 mm and a thickness of 0.7 mm.
- An ITO electrode with a solid pattern constituting a counter electrode is formed as a first layer on the substrate, and a CVD (chemical vapor deposition) electrode is formed as a second layer on top of the first layer counter electrode.
- a SiN (silicon nitride) film was formed using a method.
- As the second layer SiN film a film having a thickness of 300 nm and functioning as an interlayer insulating film was used.
- a comb-shaped pixel electrode formed by patterning an ITO film as a third layer is arranged on the second layer of SiN film, and two pixels, a first pixel and a second pixel, are formed.
- the size of each pixel was 10 mm in length and about 5 mm in width.
- the first-layer counter electrode and the third-layer pixel electrode were electrically insulated by the action of the second-layer SiN film.
- the third layer pixel electrode has a comb-shaped shape in which a plurality of electrode elements each having a width of 3 ⁇ m and whose central portion is bent at an internal angle of 160° are arranged in parallel with an interval of 6 ⁇ m.
- Each pixel had a first region and a second region separated by a line connecting the bent portions of the plurality of electrode elements.
- a glass substrate (second glass substrate) having columnar spacers with a height of 4 ⁇ m on which an ITO film is formed on the front and back surfaces of the substrate with electrodes (first glass substrate) prepared above is prepared. ) by spin coating.
- the coating surface was subjected to alignment treatment by irradiating 300 mJ/cm 2 of linearly polarized ultraviolet light with a wavelength of 254 nm with an extinction ratio of 26:1 via a polarizing plate to obtain a substrate with a liquid crystal alignment film.
- the liquid crystal alignment film formed on the electrode-attached substrate is aligned so that the direction that equally divides the interior angle of the pixel bend and the alignment direction of the liquid crystal is perpendicular to the liquid crystal alignment film formed on the second glass substrate.
- a liquid crystal cell is installed between two polarizing plates arranged so that the polarization axes are perpendicular to each other, and the backlight is turned on so that the transmitted light intensity in the first region of the first pixel is the smallest.
- the rotation angle required when adjusting the arrangement angle of the liquid crystal cell and then rotating the liquid crystal cell so that the intensity of transmitted light in the second region of the first pixel was minimized was calculated as the angle ⁇ .
- the first area and the second area were compared, and a similar angle ⁇ was calculated. Then, the average value of the angle ⁇ between the first pixel and the second pixel was calculated as the rotation angle ⁇ of the liquid crystal cell.
- liquid crystal alignment agents AL-7 to AL-11 and AL-C4 to AL-C5 obtained in Examples 3-7 to 3-11 and Comparative Examples 3-4 to 3-5 were applied to an ITO substrate by spin coating, respectively. It was applied at. After drying on a hot plate at 80°C for 2 minutes, baking was performed in an IR oven at 230°C for 30 minutes to form a coating film with a thickness of 100 nm.
- the coating surface was irradiated with 300 mJ/ cm2 of linearly polarized ultraviolet rays at a wavelength of 254 nm with an extinction ratio of 26:1 through a polarizing plate for alignment treatment, and then baked in an IR oven at 230°C for 30 minutes to display a liquid crystal display.
- the liquid crystal aligning film obtained from the liquid crystal aligning agent using the diamine component containing the specific diamine is compared to the liquid crystal aligning film obtained from the liquid crystal aligning agent using the diamine component not containing the specific diamine. , molecular weight reduction during firing was suppressed, and a high voltage retention rate was exhibited even after long exposure to high temperatures. Moreover, a liquid crystal alignment film obtained from a liquid crystal aligning agent using a diamine component containing a specific diamine exhibited high liquid crystal alignment stability and high film hardness.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Nonlinear Science (AREA)
- Crystallography & Structural Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Mathematical Physics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
- Liquid Crystal (AREA)
Abstract
Description
また、スマートフォンなどのモバイル用途及びカーナビゲーションなどに用いられる液晶表示素子では、軽量化の観点から、液晶パネルを構成する基板(例えば、ガラス基板など)の厚みを薄くすることがある。このため、基板が薄型化することに伴い発生する液晶配向膜の膜削れを抑制する観点から、膜強度の高い液晶配向膜が求められることがある。
さらには、IPS方式やFFS駆動方式においては、液晶配向の安定性も重要となる。配向の安定性が小さいと、液晶を長時間駆動させた際に液晶が初期の状態に戻らなくなり、コントラストの低下や焼き付き(以下、AC残像と称する。)の原因となるため、AC残像が抑制された液晶配向膜も求められる。
1.下記式(dA-1)~(dA-6)のいずれかで表されるジアミン。
3.前記ジアミン成分が、分子内にウレア結合、アミド結合、カルボキシ基及びヒドロキシ基からなる群から選ばれる少なくとも1種の基を有するジアミンをさらに含む、上記2に記載の重合体。
4.上記1に記載のジアミンの使用量が、前記ジアミン成分に対して、5モル%以上である、上記2または3に記載の重合体。
5.前記重合体が、前記ジアミン成分とテトラカルボン酸成分との重合反応により得られ、前記テトラカルボン酸成分が、テトラカルボン酸二無水物又はその誘導体を含む、上記2~4のいずれか一項に記載の重合体。
6.前記テトラカルボン酸二無水物又はその誘導体が、非環式脂肪族テトラカルボン酸二無水物、脂環式テトラカルボン酸二無水物、芳香族テトラカルボン酸二無水物、又はこれらの誘導体である、上記5に記載の重合体。
7.前記テトラカルボン酸二無水物又はその誘導体が、
1,2,3,4-ブタンテトラカルボン酸二無水物である非環式脂肪族テトラカルボン酸二無水物;
1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2-ジメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジクロロ-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2,3,4-テトラメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジフルオロ-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ビス(トリフルオロメチル)-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2,3,4-シクロペンタンテトラカルボン酸二無水物、1,2,4,5-シクロヘキサンテトラカルボン酸二無水物、3,3’,4,4’-ジシクロヘキシルテトラカルボン酸二無水物、2,3,5-トリカルボキシシクロペンチル酢酸二無水物、4-(2,5-ジオキソテトラヒドロフラン-3-イル)テトラヒドロナフタレン-1,2-ジカルボン酸無水物、5-(2,5-ジオキソテトラヒドロフラン-3-イル)-3a,4,5,9b-テトラヒドロナフト[1,2-c]フラン-1,3-ジオン、5-(2,5-ジオキソテトラヒドロフラン-3-イル)-8-メチル-3a,4,5,9b-テトラヒドロナフト[1,2-c]フラン-1,3-ジオン、ビシクロ[2.2.2]オクタ-7-エン-2,3,5,6-テトラカルボン酸二無水物、ビシクロ[2.2.2]オクタン-2,3,5,6-テトラカルボン酸二無水物、および2,4,6,8-テトラカルボキシビシクロ[3.3.0]オクタン-2:4,6:8-二無水物から選ばれる脂環式テトラカルボン酸二無水物;
ピロメリット酸二無水物、3,3’,4,4’-ベンゾフェノンテトラカルボン酸二無水物、3,3’,4,4’-ジフェニルスルホンテトラカルボン酸二無水物、1,4,5,8-ナフタレンテトラカルボン酸二無水物、2,3,6,7-ナフタレンテトラカルボン酸二無水物、3,3’,4,4’-ジフェニルエーテルテトラカルボン酸二無水物、3,3’,4,4’-ビフェニルテトラカルボン酸二無水物、2,2’,3,3’-ビフェニルテトラカルボン酸二無水物、4,4’-ビス(3,4-ジカルボキシフェノキシ)-2,2-ジフェニルプロパン二無水物、エチレングリコールビスアンヒドロトリメリテート、4,4’-(ヘキサフルオロイソプロピリデン)ジフタル酸無水物、4,4’-カルボニルジフタル酸無水物、4,4’-(1,4-フェニレンジオキシ)ビス(フタル酸無水物)、および4,4’-(1,4-フェニレンジメチレン)ビス(フタル酸無水物)から選ばれる芳香族テトラカルボン酸二無水物;または
これらの誘導体である、上記5~6のいずれか一項に記載の重合体。
8.上記2~7のいずれか一項に記載の重合体を含有することを特徴とする液晶配向剤。
9.さらに、上記1に記載のジアミンを含有しないジアミン成分を用いて得られるポリイミド前駆体及び該ポリイミド前駆体のイミド化物であるポリイミドからなる群から選ばれる少なくとも1種の重合体(B)を含有する、上記8に記載の液晶配向剤。
10.前記重合体(B)が、前記ジアミン成分とテトラカルボン酸成分との重合反応により得られ、前記テトラカルボン酸成分が、テトラカルボン酸二無水物又はその誘導体を含む、上記9に記載の液晶配向剤。
11.前記液晶配向剤が、オキシラニル基、オキセタニル基、ブロックイソシアネート基、オキサゾリン基、シクロカーボネート基、ヒドロキシ基及びアルコキシ基から選ばれる少なくとも1種の置換基を有する架橋性化合物(c-1)、並びに重合性不飽和基を有する架橋性化合物(c-2)からなる群から選ばれる少なくとも1種の架橋性化合物、官能性シラン化合物、金属キレート化合物、硬化促進剤、界面活性剤、酸化防止剤、増感剤、防腐剤、得られる液晶配向膜の誘電率や電気抵抗を調整するための化合物、並びにイミド化を促進するための化合物から選ばれる少なくとも一種の添加剤を更に含有する、請求項8~10のいずれか一項に記載の液晶配向剤。
12.上記8~11のいずれか1項に記載の液晶配向剤から得られる液晶配向膜。
13.上記12に記載の液晶配向膜を具備する液晶表示素子。
14.下記の工程(1)~(3)を含む、液晶表示素子の製造方法。
工程(1):上記8~11のいずれか一項に記載の液晶配向剤を基板上に塗布する工程
工程(2):塗布した前記液晶配向剤を焼成し、膜を得る工程
工程(3):工程(2)で得られた前記膜に配向処理する工程
15.前記配向処理が、光配向処理である、上記14に記載の液晶表示素子の製造方法。
さらには、本発明のジアミンは、液晶配向膜を構成する重合体の原料として使用したときに、膜強度が高く、AC残像が抑制され、且つ、高温下に長時間曝された後であっても電圧保持率が高い液晶配向膜を得ることができる液晶配向剤、該液晶配向剤から得られる液晶配向膜及びそれを用いた液晶表示素子を提供することができる。
以下の説明において、「ハロゲン原子」として、フッ素原子、塩素原子、臭素原子、ヨウ素原子等が挙げられる。「Boc」は、tert-ブトキシカルボニル基を表し、「*」は結合位置を表す。
下記式(di-1)で表されるジアミンに、二炭酸ジ-tert-ブチルなどのアミノ保護試薬を反応させて、アミノ基がBoc基で保護された化合物(di-2)を得る。ここで、式(i)中のYは、ジアミンから2つのアミノ基を除いた2価の有機基を表し、ジアミンとして、4,4’-ジアミノジフェニルアミン、又は4,4’-ジアミノジフェニル-N-メチルアミンが挙げられる。
式(di-2)で表される化合物に、テトラカルボン酸二無水物を反応させて、下記式(di-3)で表される化合物を得る。ここで、式(ii)中のXは、テトラカルボン酸二無水物から2つの酸無水基を除いた4価の有機基を表し、テトラカルボン酸二無水物として、ピロメリット酸二無水物、3,3’,4,4’-ベンゾフェノンテトラカルボン酸二無水物、又は3,3’,4,4’-ビフェニルテトラカルボン酸二無水物が挙げられる。また、式(ii)中のYは、式(i)と同義である。
上記化合物(di-4)に、塩酸などの無機酸を反応させて、脱保護反応を行い、本発明のジアミン化合物を得る。反応温度は、特に限定されないが、0~100℃で反応させてもよい。
上記触媒イミド化は、式(di-3)で表される化合物の溶液に、塩基性触媒と酸無水物とを添加し、好ましくは0~120℃、より好ましくは0~100℃で反応させることにより行うことができる。塩基性触媒の量は、式(di-3)で表される化合物が有するアミック酸基の好ましくは、0.5~30モル倍であり、より好ましくは2~20モル倍である。酸無水物の量は、式(di-3)で表される化合物が有するアミック酸基の、好ましくは1~50モル倍であり、より好ましくは1~30モル倍である。塩基性触媒としては、ピリジン、トリエチルアミン、トリメチルアミン、トリブチルアミン又はトリオクチルアミンなどを挙げることができ、なかでも、ピリジンは反応を進行させるのに適度な塩基性を持つので好ましい。酸無水物としては、無水酢酸、無水トリメリット酸又は無水ピロメリット酸などを挙げることができ、中でも無水酢酸を用いると反応終了後の精製が容易となるので好ましい。
本発明の重合体(P)は、上記ジアミン(0)を含有するジアミン成分を用いて得られるポリイミド前駆体、又は該ポリイミド前駆体のイミド化物であるポリイミドである。ここにおいて、ポリイミド前駆体は、ポリアミック酸、ポリアミック酸エステルなどのイミド化することによりポリイミドを得ることができる重合体である。
上記重合体(P)のポリイミド前駆体であるポリアミック酸(P’)は、上記ジアミン(0)を含有するジアミン成分とテトラカルボン酸成分との重合反応により得ることができる。上記ジアミン(0)は、一種を単独で用いてもよく、二種以上を組み合わせて用いてもよい。
ジアミン(0)の使用量は、全ジアミン成分に対して、5モル%以上が好ましく、10モル%以上がより好ましく、20モル%以上がさらに好ましい。
上記ベンゼン環、ビフェニル構造、又はナフタレン環上の1つ以上の水素原子は1価の基で置換されてもよく、該1価の基としては、ハロゲン原子、炭素数1~3のアルキル基、炭素数2~3のアルケニル基、炭素数1~3のアルコキシ基、炭素数1~3のフルオロアルキル基、炭素数2~3のフルオロアルケニル基、炭素数1~3のフルオロアルコキシ基、炭素数2~3のアルキルオキシカルボニル基、シアノ基、ニトロ基等が挙げられる。)
上記その他のジアミンは、目的に応じて種々用いることができるが、例えば、液晶配向膜として用いた場合に電圧保持特性を高める観点から、分子内にウレア結合、アミド結合、カルボキシ基及びヒドロキシ基からなる群から選ばれる少なくとも1種の基を有するジアミン、3,3’-ジアミノジフェニルエーテル、3,4’-ジアミノジフェニルエーテル、4,4’-ジアミノジフェニルエーテル、及び、上記特定の窒素原子含有構造を有するジアミン、からなる群から選ばれる少なくとも1種のジアミンが好ましい。
上記その他のジアミンの使用量は、重合体(P)の製造に使用される全ジアミン成分に対して、好ましくは10~90モル%であり、より好ましくは20~80モル%である。
上記ポリアミック酸(P’)を製造する場合、ジアミン成分と反応させるテトラカルボン酸成分は、テトラカルボン酸二無水物だけでなく、テトラカルボン酸、テトラカルボン酸ジハライド、テトラカルボン酸ジアルキルエステル、又はテトラカルボン酸ジアルキルエステルジハライドなどのテトラカルボン酸二無水物の誘導体を用いることもできる。
脂環式テトラカルボン酸二無水物は、脂環式構造に結合する少なくとも1つのカルボキシ基を含めて4つのカルボキシ基が分子内脱水することにより得られる酸二無水物である。但し、これら4つのカルボキシ基はいずれも芳香環には結合していない。また、脂環式構造のみで構成されている必要はなく、その一部に鎖状炭化水素構造や芳香環構造を有していてもよい。
芳香族テトラカルボン酸二無水物は、芳香環に結合する少なくとも1つのカルボキシ基を含めて4つのカルボキシ基が分子内脱水することにより得られる酸二無水物である。但し、芳香環構造のみで構成されている必要はなく、その一部に鎖状炭化水素構造や脂環式構造を有していてもよい。
1,2,3,4-ブタンテトラカルボン酸二無水物等の非環式脂肪族テトラカルボン酸二無水物;1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2-ジメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジクロロ-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2,3,4-テトラメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジフルオロ-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ビス(トリフルオロメチル)-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2,3,4-シクロペンタンテトラカルボン酸二無水物、1,2,4,5-シクロヘキサンテトラカルボン酸二無水物、3,3’,4,4’-ジシクロヘキシルテトラカルボン酸二無水物、2,3,5-トリカルボキシシクロペンチル酢酸二無水物、4-(2,5-ジオキソテトラヒドロフラン-3-イル)テトラヒドロナフタレン-1,2-ジカルボン酸無水物、5-(2,5-ジオキソテトラヒドロフラン-3-イル)-3a,4,5,9b-テトラヒドロナフト[1,2-c]フラン-1,3-ジオン、5-(2,5-ジオキソテトラヒドロフラン-3-イル)-8-メチル-3a,4,5,9b-テトラヒドロナフト[1,2-c]フラン-1,3-ジオン、ビシクロ[2.2.2]オクタ-7-エン-2,3,5,6-テトラカルボン酸二無水物、ビシクロ[2.2.2]オクタン-2,3,5,6-テトラカルボン酸二無水物、2,4,6,8-テトラカルボキシビシクロ[3.3.0]オクタン-2:4,6:8-二無水物等の脂環式テトラカルボン酸二無水物;ピロメリット酸二無水物、3,3’,4,4’-ベンゾフェノンテトラカルボン酸二無水物、3,3’,4,4’-ジフェニルスルホンテトラカルボン酸二無水物、1,4,5,8-ナフタレンテトラカルボン酸二無水物、2,3,6,7-ナフタレンテトラカルボン酸二無水物、3,3’,4,4’-ジフェニルエーテルテトラカルボン酸二無水物、3,3’,4,4’-ビフェニルテトラカルボン酸二無水物、2,2’,3,3’-ビフェニルテトラカルボン酸二無水物、4,4’-ビス(3,4-ジカルボキシフェノキシ)-2,2-ジフェニルプロパン二無水物、エチレングリコールビスアンヒドロトリメリテート、4,4’-(ヘキサフルオロイソプロピリデン)ジフタル酸無水物、4,4’-カルボニルジフタル酸無水物、4,4’-(1,4-フェニレンジオキシ)ビス(フタル酸無水物)、又は4,4’-(1,4-フェニレンジメチレン)ビス(フタル酸無水物)等の芳香族テトラカルボン酸二無水物;そのほか、特開2010-97188号公報に記載のテトラカルボン酸二無水物等。
本発明の液晶配向剤は、重合体(P)、及び必要に応じて使用されるその他の成分が、好ましくは適当な溶媒中に分散又は溶解してなる液状の組成物である。
本発明の液晶配向剤に含まれる重合体の合計含有量は、形成させようとする塗膜の厚みの設定によっても適宜変更できるが、均一で欠陥のない塗膜を形成させるという点から1質量%以上が好ましく、溶液の保存安定性の点からは、10質量%以下が好ましい。特に好ましい重合体の合計含有量は、2~8質量%である。
本発明に用いられる重合体(P)の含有量は、液晶配向剤に含有される重合体の合計に対し、1~100質量%が好ましく、10~100質量%がより好ましく、20~100質量%が特に好ましい。
なかでも、電圧保持率を維持する点および残留DC由来の残像を少なくする点から、重合体(B)がより好ましい。
上記その他の重合体は、一種を単独で使用してもよく、また二種以上を組み合わせて使用してもよい。その他の重合体の含有割合は、液晶配向剤中に含まれる重合体の合計100質量部に対して、90質量部以下が好ましく、10~90質量部がより好ましく、20~80質量部が更に好ましい。
上記重合体(B)の製造に用いられるテトラカルボン酸成分の具体例は、好ましい具体例を含めて、重合体(P)で例示した化合物と同様の化合物が挙げられる。重合体(B)の製造に用いられるテトラカルボン酸成分は、より好ましくは、ベンゼン環、シクロブタン環、シクロペンタン環及びシクロヘキサン環よりなる群から選ばれる少なくとも一種の部分構造を有するテトラカルボン酸二無水物又はこれらの誘導体を含むことがより好ましく、上記特定のテトラカルボン酸誘導体がさらに好ましく、上記特定のテトラカルボン酸誘導体のより好ましい具体例を用いることが最も好ましい。重合体(B)の製造に用いられるテトラカルボン酸成分は、本発明の効果を好適に得る観点から、非環式脂肪族テトラカルボン酸二無水物、脂環式テトラカルボン酸二無水物又はこれらの誘導体が好ましい。
また、上記特定のテトラカルボン酸誘導体の使用量は、重合体(B)の製造に使用される全テトラカルボン酸成分に対して、10モル%以上が好ましく、20モル%以上がより好ましく、50モル%以上がさらに好ましい。
上記ジアミン(c)を用いる場合、その使用量は、重合体(B)の製造に用いられる全ジアミン成分の10モル%以上が好ましく、20モル%以上がより好ましい。ジアミン(c)以外のジアミンを用いる場合、その使用量は、重合体(B)の製造に用いられる全ジアミン成分の90モル%以下が好ましく、80モル%以下がより好ましい。
ポリアミック酸の製造は、ジアミン成分とテトラカルボン酸成分とを有機溶媒中で反応させることにより行われる。ポリアミック酸の製造反応に供されるテトラカルボン酸成分とジアミン成分との使用割合は、ジアミン成分のアミノ基1当量に対して、テトラカルボン酸成分の酸無水物基が0.5~2当量となる割合が好ましく、さらに好ましくは0.8~1.2当量である。通常の重縮合反応と同様に、このテトラカルボン酸成分の酸無水物基の当量が1当量に近いほど、生成するポリアミック酸の分子量は大きくなる。
ポリアミック酸の製造における反応温度は-20~150℃が好ましく、0~100℃がより好ましい。また、反応時間は0.1~24時間が好ましく、0.5~12時間がより好ましい。ポリアミック酸の製造は任意の濃度で行うことができるがポリアミック酸の濃度は好ましくは1~50質量%、より好ましくは5~30質量%である。反応初期は高濃度で行い、その後、溶媒を追加することもできる。
ポリアミック酸エステルは、例えば、[I]上記の方法で得られたポリアミック酸とエステル化剤とを反応させる方法、[II]テトラカルボン酸ジエステルとジアミンとを反応させる方法、[III]テトラカルボン酸ジエステルジハロゲン化物とジアミンとを反応させる方法、などの既知の方法によって得ることができる。
ポリイミドは、上記ポリアミック酸又はポリアミック酸エステルなどのポリイミド前駆体を閉環(イミド化)させることによりポリイミドを得ることができる。なお、本明細書でいうイミド化率とは、テトラカルボン酸二無水物又はその誘導体由来のイミド基とカルボキシ基(又はその誘導体)との合計量に占めるイミド基の割合のことである。イミド化率は、必ずしも100%である必要はなく、用途や目的に応じて任意に調整できる。
ポリイミド前駆体を溶液中で熱イミド化させる場合の温度は、好ましくは100~400℃であり、より好ましくは120~250℃であり、イミド化反応により生成する水を系外に除きながら行う方が好ましい。
本発明におけるポリイミド前駆体やポリイミドの末端の例としては、アミノ基、カルボキシ基、酸無水物基又は後述する末端封止剤に由来する基が挙げられる。アミノ基、カルボキシ基、酸無水物基は通常の縮合反応により得るか、又は以下の末端封止剤を用いて末端を封止することにより得ることができる。
末端封止剤の使用割合は、使用するジアミン成分の合計100モル部に対して、0.01~20モル部とすることが好ましく、0.01~10モル部とすることがより好ましい。
本発明の液晶配向剤は、上記重合体(P)、上記その他の重合体、及び上記有機溶媒に加えて、それ以外の成分(以下、添加剤成分ともいう。)を含有してもよい。かかる添加剤成分としては、例えば、オキシラニル基、オキセタニル基、ブロックイソシアネート基、オキサゾリン基、シクロカーボネート基、ヒドロキシ基及びアルコキシ基から選ばれる少なくとも1種の置換基を有する架橋性化合物(c-1)、並びに重合性不飽和基を有する架橋性化合物(c-2)からなる群から選ばれる少なくとも1種の架橋性化合物、官能性シラン化合物、金属キレート化合物、硬化促進剤、界面活性剤、酸化防止剤、増感剤、防腐剤、得られる液晶配向膜の誘電率や電気抵抗を調整するための化合物、イミド化を促進するための化合物などが挙げられる。
本発明の液晶配向剤に含有される上記架橋性化合物(c-1)及び(c-2)の含有量は、液晶配向剤に含まれる重合体成分100質量部に対して、0.1~30質量部が好ましく、より好ましくは0.1~20質量部、さらに好ましくは5~20質量部である。
特に好ましい固形分濃度の範囲は、基板に液晶配向剤を塗布する際に用いる方法によって異なる。例えばスピンコート法を用いる場合には、固形分濃度が1.5~4.5質量%であることが特に好ましい。印刷法による場合には、固形分濃度を3~9質量%とし、それにより溶液粘度を12~50mPa・sとすることが特に好ましい。インクジェット法による場合には、固形分濃度を1~5質量%とし、それにより、溶液粘度を3~15mPa・sとすることが特に好ましい。重合体組成物を調製する際の温度は、好ましくは10~50℃であり、より好ましくは20~30℃である。
本発明に係る液晶表示素子は、上記液晶配向剤を用いて形成した液晶配向膜を具備する。液晶表示素子の動作モードは特に限定せず、例えば、TN型、STN型、垂直配向型(VA-MVA型、VA-PVA型などを含む。)、面内スイッチング型(IPS型、FFS型)、光学補償ベンド型(OCB型)など種々の動作モードに適用することができる。
工程(1)は、液晶配向剤を基板上に塗布する工程である。工程(1)の具体例は以下のとおりである。
パターニングされた透明導電膜が設けられている基板の一面に、液晶配向剤を、例えばロールコーター法、スピンコート法、印刷法、インクジェット法などの適宜の塗布方法により塗布する。ここで基板の材質としては、透明性の高い基板であれば特に限定されず、ガラス、窒化珪素とともに、アクリル、ポリカーボネート等のプラスチック等を用いることもできる。また、反射型の液晶表示素子では、片側の基板のみにならば、シリコンウエハー等の不透明な物でも使用でき、この場合の電極にはアルミニウム等の光を反射する材料も使用できる。また、IPS型又はFFS型の液晶表示素子を製造する場合には、櫛歯型にパターニングされた透明導電膜又は金属膜からなる電極が設けられている基板と、電極が設けられていない対向基板とを用いる。
IPS型の液晶表示素子において使用される櫛歯電極基板であるIPS基板は、例えば、基材と、基材上に形成され、櫛歯状に配置された複数の線状電極と、基材上に線状電極を覆うように形成された液晶配向膜とを有する。
なお、FFS型の液晶表示素子において使用される櫛歯電極基板であるFFS基板は、例えば、基材と、基材上に形成された面電極と、面電極上に形成された絶縁膜と、絶縁膜上に形成され、櫛歯状に配置された複数の線状電極と、絶縁膜上に線状電極を覆うように形成された液晶配向膜とを有する。
工程(2)は、基板上に塗布した液晶配向剤を焼成し、膜を形成する工程である。工程(2)の具体例は以下のとおりである。
工程(1)において液晶配向剤を基板上に塗布した後は、ホットプレート、熱風循環型オーブン又はIR(赤外線)型オーブンなどの加熱手段により、溶媒を蒸発させたり、ポリアミック酸の熱イミド化を行ったりすることができる。液晶配向剤を塗布した後の乾燥、焼成工程は、任意の温度と時間を選択することができ、複数回行ってもよい。液晶配向剤を焼成する温度としては、例えば40~180℃で行うことができる。プロセスを短縮する観点で、40~150℃で行ってもよい。焼成時間としては特に限定されないが、1~10分又は、1~5分が挙げられる。ポリアミック酸の熱イミド化を行う場合には、上記工程の後、例えば150~300℃、又は150~250℃で焼成する工程を追加してもよい。焼成時間としては特に限定されないが、5~40分、又は、5~30分の焼成時間が挙げられる。
焼成後の膜状物の膜厚は、薄すぎると液晶表示素子の信頼性が低下する場合があるので、5~300nmが好ましく、10~200nmがより好ましい。
工程(3)は、場合により、工程(2)で得られた膜に配向処理する工程である。即ち、IPS方式又はFFS方式等の水平配向型の液晶表示素子では該塗膜に対し配向能付与処理を行う。一方、VA方式又はPSAモード等の垂直配向型の液晶表示素子では、形成した塗膜をそのまま液晶配向膜として使用することができるが、該塗膜に対し配向能付与処理を施してもよい。液晶配向膜の配向処理方法としては、ラビング配向処理法、光配向処理法が挙げられる。光配向処理法としては、上記膜状物の表面に、一定方向に偏向された放射線を照射し、場合により、好ましくは、150~250℃の温度で加熱処理を行い、液晶配向性(液晶配向能ともいう)を付与する方法が挙げられる。放射線としては、100~800nmの波長を有する紫外線又は可視光線を用いることができる。なかでも、好ましくは100~400nm、より好ましくは、200~400nmの波長を有する紫外線である。
上記のようにして液晶配向膜が形成された基板を2枚準備し、対向配置した2枚の基板間に液晶を配置する。具体的には以下の2つの方法が挙げられる。
第一の方法は、先ず、それぞれの液晶配向膜が対向するように間隙(セルギャップ)を介して2枚の基板を対向配置する。次いで、2枚の基板の周辺部をシール剤を用いて貼り合わせ、基板表面及びシール剤により区画されたセルギャップ内に液晶組成物を注入充填して膜面に接触した後、注入孔を封止する。
なお、塗膜に対してラビング配向処理を行った場合には、2枚の基板は、各塗膜におけるラビング方向が互いに所定の角度、例えば直交又は逆平行となるように対向配置される。
シール剤としては、例えば硬化剤及びスペーサーとしての酸化アルミニウム球を含有するエポキシ樹脂等を用いることができる。
上記液晶組成物としては、特に制限はなく、少なくとも一種の液晶化合物(液晶分子)を含む組成物であって、ネマチック相を呈する液晶組成物(以下、ネマチック液晶ともいう。)、スメクチック相を呈する液晶、又はコレステリック相を呈する液晶組成物を挙げることができ、そのなかでもネマチック液晶が好ましい。また、誘電率異方性が正または負の各種の液晶組成物を用いることができる。なお、以下では、誘電率異方性が正の液晶組成物を、ポジ型液晶ともいい、誘電異方性が負の液晶組成物を、ネガ型液晶ともいう。
上記液晶組成物は、フッ素原子、ヒドロキシ基、アミノ基、フッ素原子含有基(例えば、トリフルオロメチル基)、シアノ基、アルキル基、アルコキシ基、アルケニル基、イソチオシアネート基、複素環、シクロアルカン、シクロアルケン、ステロイド骨格、ベンゼン環、又はナフタレン環を有する液晶化合物を含んでもよく、分子内に液晶性を発現する剛直な部位(メソゲン骨格)を2つ以上有する化合物(例えば、剛直な二つのビフェニル構造、又はターフェニル構造がアルキル基で連結されたバイメソゲン化合物)を含んでもよい。
また、上記液晶組成物は、液晶配向性を向上させる観点から、添加物をさらに含有してもよい。このような添加物は、重合性基を有する化合物などの光重合性モノマー;光学活性な化合物(例:メルク(株)社製のS-811など);酸化防止剤;紫外線吸収剤;色素;消泡剤;重合開始剤;又は重合禁止剤などが挙げられる。
ポジ型液晶としては、メルク社製のZLI-2293、ZLI-4792、MLC-2003、MLC-2041、MLC-3019、又はMLC-7081などが挙げられる。
ネガ型液晶としては、例えばメルク社製のMLC-6608、MLC-6609、MLC-6610、MLC-7026、又はMLC-7026-100などが挙げられる。
また、重合性基を有する化合物を含有する液晶として、メルク社製のMLC-3023が挙げられる。
また、本発明の液晶配向剤は、電極を備えた一対の基板の間に液晶層を有してなり、上記一対の基板の間に活性エネルギー線及び熱の少なくとも一方により重合する重合性基を含む液晶配向膜を配置し、電極間に電圧を印加する工程を経て製造される液晶表示素子(SC-PVAモード型の液晶表示素子)にも好ましく用いられる。
重合性化合物を含有する液晶組成物を注入又は滴下する点以外は上記(4)と同様に実施される。重合性化合物としては、例えばアクリレート基やメタクリレート基などの重合性不飽和基を分子内に1個以上有する重合性化合物を挙げることができる。
上記(4)と同様にした後、後述する紫外線を照射する工程を経て液晶表示素子を製造する方法を採用してもよい。この方法によれば、上記PSA型液晶表示素子を製造する場合と同様に、少ない光照射量で応答速度に優れた液晶表示素子を得ることができる。重合性基を有する化合物は、上記重合性不飽和基を分子内に1個以上有する化合物であってもよく、その含有量は、全ての重合体成分100質量部に対して0.1~30質量部であることが好ましく、より好ましくは1~20質量部である。また、上記重合性基は液晶配向剤に用いる重合体が有していてもよく、このような重合体としては、例えば上記光重合性基を末端に有するジアミンを含むジアミン成分を反応に用いて得られる重合体が挙げられる。
上記(4-2)又は(4-3)で得られた一対の基板の有する導電膜間に電圧を印加した状態で液晶セルに光照射する。ここで印加する電圧は、例えば5~50Vの直流又は交流とすることができる。また、照射する光としては、例えば150~800nmの波長の光を含む紫外線及び可視光線を用いることができるが、300~400nmの波長の光を含む紫外線が好ましい。照射光の光源としては、例えば低圧水銀ランプ、高圧水銀ランプ、重水素ランプ、メタルハライドランプ、アルゴン共鳴ランプ、キセノンランプ、エキシマレーザーなどを使用することができる。光の照射量は、好ましくは1,000~200,000J/m2であり、より好ましくは1,000~100,000J/m2である。
DA-W1~DA-W6:それぞれ、下記式(DA-W1)~(DA-W6)で表される化合物(なお、下記式(DA-W1)~(DA-W6)で表される化合物は、上記式(dA-1)~(dA-6)で表されるジアミンと同じである。)
NMP:N-メチル-2-ピロリドン
GBL:γ-ブチロラクトン
BCS:エチレングリコールモノブチルエーテル
AcOEt:酢酸エチル
MeCN:アセトニトリル
THF:テトラヒドロフラン
CHCl3:クロロホルム
E型粘度計TVE-22H(東機産業社製)を用い、サンプル量1.1mL、コーンロータTE-1(1°34’、R24)を用いて、温度25℃で測定した。
下記の常温GPC(ゲル浸透クロマトグラフィー)装置によって測定し、ポリエチレングリコール、ポリエチレンオキサイド換算値として算出した。
GPC装置:SSC-7200(センシュー科学社製)、カラム:GPC KD-803、GPC KD-805(昭和電工社製)の直列、カラム温度:50℃、溶離液:N,N-ジメチルホルムアミド(添加剤として、臭化リチウム一水和物(LiBr・H2O)が30mmol/L、リン酸・無水結晶(o-リン酸)が30mmol/L、テトラヒドロフラン(THF)が10mL/L)、流速:1.0mL/分
検量線作成用標準サンプル:TSK 標準ポリエチレンオキサイド(分子量;約900,000、150,000、100,000及び30,000)(東ソー社製)及びポリエチレングリコール(分子量;約12,000、4,000及び1,000)(ポリマーラボラトリー社製)。
DA-W1~DA-W6は、文献等未公開の新規化合物であり、以下に合成法を詳述する。
装置:フーリエ変換型超伝導核磁気共鳴装置(FT-NMR)「AVANCE III」(BRUKER社製)500MHz
溶媒:重水素化N,N-ジメチルスルホキシド([D6]-DMSO)
標準物質:テトラメチルシラン(TMS)
1H-NMR(500MHz,[D6]-DMSO):δ(ppm)=8.33-8.36(m,4H),8.04-8.06(d,2H),7.76(s,2H),7.13-7.15(d,4H),6.85-6.90(m,8H),6.58-6.59(d,4H),4.90(s,4H).
1H-NMR(500MHz,[D6]-DMSO):δ(ppm)=8.33-8.36(m,4H),8.04-8.05(d,2H),7.15-7.17(d,4H),6.90-6.92(d,4H),6.68-6.70(d,4H),6.62-6.64(d,4H),5.08(s,4H),3.19(s,6H).
1H-NMR(500MHz,[D6]-DMSO):δ(ppm)=8.28(s,2H),7.78(s,2H),7.16-7.18(d,4H),6.84-6.90(m,8H),6.57-6.59(d,4H),4.84(s,4H).
1H-NMR(500MHz,[D6]-DMSO):δ(ppm)=8.27(s,2H),7.18-7.19(d,4H),6.90-6.92(d,4H),6.68-6.70(d,4H),6.62-6.64(d,4H),5.09(s,4H),3.31(s,6H).
1H-NMR(500MHz,[D6]-DMSO):δ(ppm)=8.23-8.25(m,2H),8.13-8.14(m,4H),7.76(s,2H),7.13-7.15(d,4H),6.84-6.89(m,8H),6.57-6.59(d,4H),4.89(s,4H).
1H-NMR(500MHz,[D6]-DMSO):δ(ppm)=8.22-8.24(d,2H),8.12-8.14(m,4H),7.15-7.17(d,4H),6.90-6.91(d,4H),6.68-6.70(d,4H),6.61-6.63(d,4H),5.09(s,4H),3.19(s,6H).
<実施例2-1>
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W1(2.56g、3.90mmol)、DA-4(0.626g、2.10mmol)及びNMP(28.7g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(0.977g、4.98mmol)及びNMP(1.85g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-A1)の溶液(粘度:563mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W1(2.15g、3.28mmol)、DA-4(0.734g、2.46mmol)、DA-8(1.04g、2.46mmol)及びNMP(35.3g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(1.42g、7.23mmol)及びNMP(3.86g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-A2)の溶液(粘度:402mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W1(2.99g、4.55mmol)、DA-4(0.731g、2.45mmol)及びNMP(27.3g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(0.153g、0.781mmol)及びNMP(1.13g)を加えて、室温で1時間撹拌した。その後、CA-2(1.31g、5.25mmol)及びNMP(9.63g)を加えて、50℃で12時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-A3)の溶液(粘度:396mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W2(2.67g、3.90mmol)、DA-4(0.627g、2.10mmol)及びNMP(30.1g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(1.06g、5.40mmol)及びNMP(2.26g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-A4)の溶液(粘度:411mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W2(2.25g、3.28mmol)、DA-4(0.734g、2.46mmol)、DA-8(1.04g、2.46mmol)及びNMP(36.2g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(1.50g、7.67mmol)及びNMP(4.33g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-A5)の溶液(粘度:396mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W3(1.89g、3.25mmol)、DA-4(0.522g、1.75mmol)及びNMP(25.9g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(0.804g、4.10mmol)及びNMP(2.99g)を加えて、室温で2時間撹拌することで、固形分濃度10質量%のポリアミック酸(PAA-A6)の溶液(粘度:237mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-W4(2.37g、3.90mmol)、DA-4(0.627g、2.10mmol)及びNMP(27.0g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-1(1.02g、5.22mmol)及びNMP(2.49g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-A7)の溶液(粘度:413mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-7(3.79g、19.0mmol)、DA-4(1.42g、4.76mmol)及びNMP(46.9g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-3(2.80g、9.52mmol)及びNMP(11.9g)を加えて、70℃で4時間撹拌した。その後、CA-1(2.52g、12.8mmol)及びNMP(18.5g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-B1)の溶液(粘度:423mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-7(2.85g、14.3mmol)、DA-4(1.42g、4.76mmol)、DA-8(2.01g、4.76mmol)及びNMP(56.5g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-3(2.80g、9.52mmol)及びNMP(10.1g)を加えて、70℃で4時間撹拌した。その後、CA-1(2.58g、13.2mmol)及びNMP(18.9g)を加えて、室温で2時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-B2)の溶液(粘度:378mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-7(3.79g、19.0mmol)、DA-4(1.42g、4.76mmol)及びNMP(46.9g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-3(2.80g、9.52mmol)及びNMP(11.9g)を加えて、70℃で4時間撹拌した。その後、CA-1(0.513g、2.62mmol)及びNMP(3.76g)を加えて、室温で1時間撹拌した。その後、CA-2(2.68g、10.7mmol)及びNMP(19.6g)を加えて、50℃で12時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-B3)の溶液(粘度:410mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-1(0.540g、4.99mmol)、DA-2(1.83g、7.49mmol)、DA-3(2.40g、7.49mmol)、DA-5(1.99g、4.99mmol)及びNMP(68.4g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-4(5.31g、23.7mmol)及びNMP(20.1g)を加えて、50℃で12時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-U1)の溶液(粘度:402mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの100mL四つ口フラスコに、DA-1(1.62g、15.0mmol)、DA-2(2.20g、9.01mmol)、DA-6(2.04g、5.97mmol)及びNMP(59.3g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-4(6.32g、28.2mmol)及びNMP(30.0g)を加えて、40℃で3時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-U2)の溶液(粘度:220mPa・s)を得た。
撹拌装置付き及び窒素導入管付きの100mL四つ口フラスコに、DA-7(4.78g、24.0mmol)、DA-4(2.39g、8.01mmol)、DA-8(3.37g、7.99mmol)及びNMP(77.3g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-3(11.3g、38.4mmol)及びNMP(82.9g)を加えて、70℃で24時間撹拌することで、固形分濃度12質量%のポリアミック酸(PAA-C1)の溶液を得た。
撹拌装置付き及び窒素導入管付きの50mL四つ口フラスコに、DA-7(2.55g、12.8mmol)、DA-9(0.487g、3.20mmol)及びNMP(22.3g)を加えて、窒素を送りながら室温で撹拌して溶解させた。その後、CA-3(4.50g、15.3mmol)及びNMP(20.5g)を加えて、50℃で16時間撹拌することで、固形分濃度15質量%のポリアミック酸(PAA-C2)の溶液(粘度:350mPa・s)を得た。
上記モノマー成分において、DA-4とDA-7の合計を100モル部とすると、各モノマー成分のモル比は、CA-1が50モル部、CA-3が39モル部、DA-7が79モル部、DA-4が21モル部となり、比較例2-1のポリアミック酸PAA-B1とほぼ同等のモノマー組成となる。一方、実施例2-1のポリアミック酸PAA-A1は、イミド構造を有し、且つ、イミド構造が隣接した位置に存在する重合体であるのに対し、比較例2-1のポリアミック酸PAA-B1は、アミック酸構造のみを有する重合体であり、得られる液晶配向膜は後述するように異なる性質を有する。
同様に、ポリアミック酸PAA-A2~PAA-A3は、それぞれポリアミック酸PAA-B2~PAA-B3とほぼ同等のモノマー組成となる。
<実施例3-1>
実施例2-1で得られたポリアミック酸(PAA-A1)の溶液を用いて、NMP、GBL及びBCSにより希釈し、室温で2時間撹拌することで、重合体固形分と各溶媒の質量比(重合体固形分:NMP:GBL:BCS)が4.5:45.5:30:20となる液晶配向剤(AL-1)を得た。
表2に示すように、使用するポリアミック酸をPAA-A1からPAA-A2~PAA-A3、PAA-B1~PAA-B3に置き換えたことを除いては実施例3-1と同様に実施することで、液晶配向剤(AL-2)~(AL-3)、(AL-C1)~(AL-C3)を得た。
調製例2-1で得られたポリアミック酸(PAA-U1)の溶液、及び実施例2-1で得られたポリアミック酸(PAA-A1)の溶液を用いて、NMP、GBL及びBCSにより希釈し、室温で2時間撹拌することで、重合体の固形分比率(PAA-U1:PAA-A1)が5:5、重合体の全固形分と各溶媒の質量比(重合体固形分:NMP:GBL:BCS)が5.5:44.5:30:20となる液晶配向剤(AL-4)を得た。
表2に示すように、使用するポリアミック酸をPAA-A1からPAA-A2~PAA-A3に置き換えたことを除いては実施例3-4と同様に実施することで、液晶配向剤(AL-5)~(AL-6)を得た。
調製例2-1で得られたポリアミック酸(PAA-U1)の溶液、及び実施例2-1で得られたポリアミック酸(PAA-A1)の溶液を用いて、NMP、GBL及びBCSにより希釈し、さらにAD-1を加え、室温で2時間撹拌することで、重合体の固形分比率(PAA-U1:PAA-A1)が5:5、重合体の全固形分と各溶媒の質量比(重合体固形分:NMP:GBL:BCS)が5.5:44.5:30:20であり、重合体の総量100質量部に対してAD-1の配合割合が5質量部となる液晶配向剤(AL-7)を得た。
表2に示すように、使用するポリアミック酸をPAA-A1からPAA-A2~PAA-A5、PAA-C1に置き換えたことを除いては実施例3-7と同様に実施することで、液晶配向剤(AL-8)~(AL-11)、(AL-C4)を得た。
調製例2-2で得られたポリアミック酸(PAA-U2)の溶液、及び調製例2-4で得られたポリアミック酸(PAA-C2)の溶液を用いて、NMP、GBL及びBCSにより希釈し、さらにAD-1~AD-3を加え、室温で2時間撹拌することで、重合体の固形分比率(PAA-U2:PAA-C2)が3:7、重合体の全固形分と各溶媒の質量比(重合体固形分:NMP:GBL:BCS)が5.5:44.5:30:20であり、重合体の総量100質量部に対してAD-1、AD-2、AD-3の配合割合がそれぞれ5質量部、1質量部、14質量部となる液晶配向剤(AL-C5)を得た。
FFSモード液晶表示素子の構成を備えた液晶セルを作製した。
始めに、電極付きの基板を準備した。基板は、30mm×50mmの長方形で、厚みが0.7mmのガラス基板を用いた。基板上には第1層目として対向電極を構成する、ベタ状のパターンを備えたITO電極が形成され、第1層目の対向電極の上には第2層目として、CVD(化学蒸着)法により成膜されたSiN(窒化珪素)膜が形成されていた。第2層目のSiN膜は、層間絶縁膜として機能する膜厚が300nmのものを用いた。第2層目のSiN膜の上には、第3層目としてITO膜をパターニングして形成された櫛歯状の画素電極が配置され、第1画素及び第2画素の2つの画素が形成されており、各画素のサイズは、縦10mmで横約5mmであった。このとき、第1層目の対向電極と第3層目の画素電極とは、第2層目のSiN膜の作用により電気的に絶縁されていた。
第3層目の画素電極は、中央部分が内角160°で屈曲した幅3μmの電極要素が6μmの間隔を開けて平行になるように複数配列された櫛歯形状を有しており、1つの画素は、複数の電極要素の屈曲部を結ぶ線を境にそれぞれ第1領域と第2領域を有していた。
次に、上記実施例3-1~3-11及び比較例3-1~3-5で得られた液晶配向剤AL-1~AL11及びAL-C1~AL-C5をそれぞれ孔径1.0μmのフィルターで濾過した後、上記で準備した電極付き基板(第1のガラス基板)の表面、及び裏面にITO膜が成膜されている高さ4μmの柱状スペーサーを有するガラス基板(第2のガラス基板)の表面にスピンコート法にて塗布した。次いで、80℃のホットプレート上で2分間乾燥させた後、230℃の熱風循環式オーブンで30分間焼成を行い、厚み100nmの塗膜を形成させた。この塗膜面に偏光板を介して消光比26:1の直線偏光した波長254nmの紫外線を300mJ/cm2照射して配向処理を施し、液晶配向膜付き基板を得た。なお、上記電極付き基板に形成する液晶配向膜は、画素屈曲部の内角を等分する方向と液晶の配向方向とが直交するように配向処理し、第2のガラス基板に形成する液晶配向膜は、液晶セルを作製した時に第1のガラス基板上の液晶の配向方向と第2のガラス基板上の液晶の配向方向とが一致するように配向処理した。上記2枚の基板を一組とし、液晶注入口を残して周囲にシール剤(三井化学社製 XN-1500T)を印刷し、もう1枚の基板を、液晶配向膜面が向き合う配向方向が0°になるようにして張り合わせた。その後、シール剤を硬化させて空セルを作製した。この空セルに減圧注入法によって、ポジ型液晶MLC-3019(メルク社製)を注入し、注入口を封止して、FFS駆動液晶セルを得た。その後、得られた液晶セルを110℃で1時間加熱し、一晩放置してから評価に使用した。
上記手順で作製したFFS駆動液晶セルを、60℃の温度下で1Vの電圧を60μsec間印加し、1000msec後の電圧を測定して、電圧がどのくらい保持できているかを電圧保持率として算出した。電圧保持率の測定には、東陽テクニカ社製のVHR-1を使用した。なお、電圧保持率の値は高いものほど良好である。結果を表3に示す。
本評価は、長期交流駆動において液晶配向膜の配向性能が低下することによって生ずる残像(AC残像ともいう。)を評価するものである。
上記で作製したFFS駆動液晶セルに対し、60℃の恒温環境下、周波数60Hzで±4Vの交流電圧を120時間印加した。その後、液晶セルの画素電極と対向電極との間をショートさせた状態にし、そのまま室温に一日放置した。上記の処理を行った液晶セルについて、電圧無印加状態における、画素の第1領域の液晶の配向方向と第2領域の液晶の配向方向とのずれを角度として算出した。具体的には、偏光軸が直交するように配置された2枚の偏光板の間に液晶セルを設置し、バックライトを点灯させ、第1画素の第1領域の透過光強度が最も小さくなるように液晶セルの配置角度を調整し、次に第1画素の第2領域の透過光強度が最も小さくなるように液晶セルを回転させたときに要する回転角度を角度Δとして算出した。第2画素でも同様に、第1領域と第2領域とを比較し、同様の角度Δを算出した。そして、第1画素と第2画素の角度Δの平均値を液晶セルの回転角度Δとして算出した。液晶配向の安定性は、この回転角度Δの値が小さいほど良好であると言える。評価基準として、上記で得られた液晶セルの回転角度Δの値が、それぞれ、0.10°以下の場合を「○」、0.10°より大きい場合を「×」とした。結果を表3に示す。
上記実施例3-7~3-11及び比較例3-4~3-5で得られた液晶配向剤AL-7~AL-11及びAL-C4~AL-C5をそれぞれITO基板にスピンコート法にて塗布した。80℃のホットプレート上で2分間乾燥させた後、230℃のIRオーブンで30分間焼成を行い、厚み100nmの塗膜を形成させた。この塗膜面に偏光板を介して消光比26:1の直線偏光した波長254nmの紫外線を300mJ/cm2照射して配向処理を施し、さらに230℃のIRオーブンで30分間焼成を行い、液晶配向膜付き基板を得た。その後、この液晶配向膜をレーヨン布(吉川化工製、YA-20R)でラビング処理(ローラー直径:120mm、ローラー回転数:1000rpm、移動速度:20mm/sec、押し込み長:0.5mm)して、ヘーズメーター(スガ試験機社製、HZ-V3)を用いて膜のHaze値(濁り度)を評価した。Haze値が小さいほど、膜が削れていない、即ち膜硬度が高いと言える。評価基準として、Haze値が0.20以下の場合を「○」、0.20より大きい場合を「×」とした。結果を表3に示す。
上記実施例3-1~3-3及び比較例3-1~3-3で得られた液晶配向剤AL-1~AL-3及びAL-C1~AL-C3をそれぞれITO基板にスピンコート法にて塗布した。80℃のホットプレート上で2分間乾燥させた後、230℃のIRオーブンで30分間焼成を行い、厚み100nmの塗膜を形成させた。この焼成後の塗膜を削り取り、分子量を測定し、焼成前後での分子量変化(焼成後の重量平均分子量÷焼成前の重量平均分子量×100[%])を評価した。結果を表3に示す。
さらに、液晶配向剤において、特定ジアミンを含有するジアミン成分から得られる重合体(P)に加えて、特定ジアミンを含有しないジアミン成分から得られる重合体(B)を用いると、電圧保持率の更なる向上が見られた。(実施例3-1~3-3と実施例3-4~3-6との比較。)
Claims (15)
- 請求項1に記載のジアミンを含むジアミン成分を用いて得られるポリイミド前駆体及び該ポリイミド前駆体のイミド化物であるポリイミドからなる群から選ばれる少なくとも1種の重合体。
- 前記ジアミン成分が、分子内にウレア結合、アミド結合、カルボキシ基及びヒドロキシ基からなる群から選ばれる少なくとも1種の基を有するジアミンをさらに含む、請求項2に記載の重合体。
- 請求項1に記載のジアミンの使用量が、前記ジアミン成分に対して、5モル%以上である、請求項2または3に記載の重合体。
- 前記重合体が、前記ジアミン成分とテトラカルボン酸成分との重合反応により得られ、前記テトラカルボン酸成分が、テトラカルボン酸二無水物又はその誘導体を含む、請求項2~4のいずれか一項に記載の重合体。
- 前記テトラカルボン酸二無水物又はその誘導体が、非環式脂肪族テトラカルボン酸二無水物、脂環式テトラカルボン酸二無水物、芳香族テトラカルボン酸二無水物、又はこれらの誘導体である、請求項5に記載の重合体。
- 前記テトラカルボン酸二無水物又はその誘導体が、
1,2,3,4-ブタンテトラカルボン酸二無水物である非環式脂肪族テトラカルボン酸二無水物;
1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2-ジメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジクロロ-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2,3,4-テトラメチル-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ジフルオロ-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,3-ビス(トリフルオロメチル)-1,2,3,4-シクロブタンテトラカルボン酸二無水物、1,2,3,4-シクロペンタンテトラカルボン酸二無水物、1,2,4,5-シクロヘキサンテトラカルボン酸二無水物、3,3’,4,4’-ジシクロヘキシルテトラカルボン酸二無水物、2,3,5-トリカルボキシシクロペンチル酢酸二無水物、4-(2,5-ジオキソテトラヒドロフラン-3-イル)テトラヒドロナフタレン-1,2-ジカルボン酸無水物、5-(2,5-ジオキソテトラヒドロフラン-3-イル)-3a,4,5,9b-テトラヒドロナフト[1,2-c]フラン-1,3-ジオン、5-(2,5-ジオキソテトラヒドロフラン-3-イル)-8-メチル-3a,4,5,9b-テトラヒドロナフト[1,2-c]フラン-1,3-ジオン、ビシクロ[2.2.2]オクタ-7-エン-2,3,5,6-テトラカルボン酸二無水物、ビシクロ[2.2.2]オクタン-2,3,5,6-テトラカルボン酸二無水物、および2,4,6,8-テトラカルボキシビシクロ[3.3.0]オクタン-2:4,6:8-二無水物から選ばれる脂環式テトラカルボン酸二無水物;
ピロメリット酸二無水物、3,3’,4,4’-ベンゾフェノンテトラカルボン酸二無水物、3,3’,4,4’-ジフェニルスルホンテトラカルボン酸二無水物、1,4,5,8-ナフタレンテトラカルボン酸二無水物、2,3,6,7-ナフタレンテトラカルボン酸二無水物、3,3’,4,4’-ジフェニルエーテルテトラカルボン酸二無水物、3,3’,4,4’-ビフェニルテトラカルボン酸二無水物、2,2’,3,3’-ビフェニルテトラカルボン酸二無水物、4,4’-ビス(3,4-ジカルボキシフェノキシ)-2,2-ジフェニルプロパン二無水物、エチレングリコールビスアンヒドロトリメリテート、4,4’-(ヘキサフルオロイソプロピリデン)ジフタル酸無水物、4,4’-カルボニルジフタル酸無水物、4,4’-(1,4-フェニレンジオキシ)ビス(フタル酸無水物)、および4,4’-(1,4-フェニレンジメチレン)ビス(フタル酸無水物)から選ばれる芳香族テトラカルボン酸二無水物;または
これらの誘導体である、請求項5~6のいずれか一項に記載の重合体。 - 請求項2~7のいずれか一項に記載の重合体を含有することを特徴とする液晶配向剤。
- さらに、請求項1に記載のジアミンを含有しないジアミン成分を用いて得られるポリイミド前駆体及び該ポリイミド前駆体のイミド化物であるポリイミドからなる群から選ばれる少なくとも1種の重合体(B)を含有する、請求項8に記載の液晶配向剤。
- 前記重合体(B)が、前記ジアミン成分とテトラカルボン酸成分との重合反応により得られ、前記テトラカルボン酸成分が、テトラカルボン酸二無水物又はその誘導体を含む、請求項9に記載の液晶配向剤。
- 前記液晶配向剤が、オキシラニル基、オキセタニル基、ブロックイソシアネート基、オキサゾリン基、シクロカーボネート基、ヒドロキシ基及びアルコキシ基から選ばれる少なくとも1種の置換基を有する架橋性化合物(c-1)、並びに重合性不飽和基を有する架橋性化合物(c-2)からなる群から選ばれる少なくとも1種の架橋性化合物、官能性シラン化合物、金属キレート化合物、硬化促進剤、界面活性剤、酸化防止剤、増感剤、防腐剤、得られる液晶配向膜の誘電率や電気抵抗を調整するための化合物、並びにイミド化を促進するための化合物から選ばれる少なくとも一種の添加剤を更に含有する、請求項8~10のいずれか一項に記載の液晶配向剤。
- 請求項8~11のいずれか1項に記載の液晶配向剤から得られる液晶配向膜。
- 請求項12に記載の液晶配向膜を具備する液晶表示素子。
- 下記の工程(1)~(3)を含む、液晶表示素子の製造方法。
工程(1):請求項8~11のいずれか一項に記載の液晶配向剤を基板上に塗布する工程
工程(2):塗布した前記液晶配向剤を焼成し、膜を得る工程
工程(3):工程(2)で得られた前記膜に配向処理する工程 - 前記配向処理が、光配向処理である、請求項14に記載の液晶表示素子の製造方法。
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202380040199.8A CN119212979A (zh) | 2022-05-13 | 2023-05-10 | 新型二胺化合物、使用该二胺得到的聚合物、液晶取向剂、液晶取向膜以及液晶显示元件 |
| KR1020247035071A KR20250009419A (ko) | 2022-05-13 | 2023-05-10 | 신규한 디아민 화합물, 그 디아민을 사용하여 얻어지는 중합체, 액정 배향제, 액정 배향막, 및 액정 표시 소자 |
| JP2024520477A JPWO2023219112A1 (ja) | 2022-05-13 | 2023-05-10 |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2022-079186 | 2022-05-13 | ||
| JP2022079186 | 2022-05-13 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2023219112A1 true WO2023219112A1 (ja) | 2023-11-16 |
Family
ID=88730274
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/JP2023/017610 Ceased WO2023219112A1 (ja) | 2022-05-13 | 2023-05-10 | 新規なジアミン化合物、該ジアミンを用いて得られる重合体、液晶配向剤、液晶配向膜、及び液晶表示素子 |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPWO2023219112A1 (ja) |
| KR (1) | KR20250009419A (ja) |
| CN (1) | CN119212979A (ja) |
| TW (1) | TW202406893A (ja) |
| WO (1) | WO2023219112A1 (ja) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118878823A (zh) * | 2024-06-17 | 2024-11-01 | 波米科技有限公司 | 一种聚合物a、制备方法及其应用 |
| CN120590629A (zh) * | 2025-08-07 | 2025-09-05 | 武汉柔显科技股份有限公司 | 聚酰亚胺前体、液晶取向剂、液晶取向膜及制造方法、液晶表示元件 |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005037920A (ja) * | 2003-06-24 | 2005-02-10 | Jsr Corp | 液晶配向剤、液晶配向膜および液晶表示素子 |
| WO2018124140A1 (ja) * | 2016-12-27 | 2018-07-05 | 日産化学工業株式会社 | 新規重合体及びジアミン化合物、液晶配向剤、液晶配向膜及び液晶表示素子 |
| WO2018190426A1 (ja) * | 2017-04-14 | 2018-10-18 | 日産化学株式会社 | 液晶配向剤、液晶配向膜及び液晶表示素子 |
| WO2019222304A1 (en) * | 2018-05-16 | 2019-11-21 | E. I. Du Pont De Nemours And Company | Polymers for use in electronic devices |
| CN112062958A (zh) * | 2020-08-20 | 2020-12-11 | 长春高琦聚酰亚胺材料有限公司 | 一种聚酰亚胺材料及其制备方法 |
| WO2021210252A1 (ja) * | 2020-04-15 | 2021-10-21 | 日産化学株式会社 | 液晶配向剤、液晶配向膜、及び液晶表示素子 |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3893659B2 (ja) | 1996-03-05 | 2007-03-14 | 日産化学工業株式会社 | 液晶配向処理方法 |
| CN101231429B (zh) | 2002-08-29 | 2014-05-14 | 日产化学工业株式会社 | 液晶取向剂及利用该取向剂的液晶显示元件 |
-
2023
- 2023-05-10 CN CN202380040199.8A patent/CN119212979A/zh active Pending
- 2023-05-10 KR KR1020247035071A patent/KR20250009419A/ko active Pending
- 2023-05-10 WO PCT/JP2023/017610 patent/WO2023219112A1/ja not_active Ceased
- 2023-05-10 JP JP2024520477A patent/JPWO2023219112A1/ja active Pending
- 2023-05-11 TW TW112117471A patent/TW202406893A/zh unknown
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005037920A (ja) * | 2003-06-24 | 2005-02-10 | Jsr Corp | 液晶配向剤、液晶配向膜および液晶表示素子 |
| WO2018124140A1 (ja) * | 2016-12-27 | 2018-07-05 | 日産化学工業株式会社 | 新規重合体及びジアミン化合物、液晶配向剤、液晶配向膜及び液晶表示素子 |
| WO2018190426A1 (ja) * | 2017-04-14 | 2018-10-18 | 日産化学株式会社 | 液晶配向剤、液晶配向膜及び液晶表示素子 |
| WO2019222304A1 (en) * | 2018-05-16 | 2019-11-21 | E. I. Du Pont De Nemours And Company | Polymers for use in electronic devices |
| WO2021210252A1 (ja) * | 2020-04-15 | 2021-10-21 | 日産化学株式会社 | 液晶配向剤、液晶配向膜、及び液晶表示素子 |
| CN112062958A (zh) * | 2020-08-20 | 2020-12-11 | 长春高琦聚酰亚胺材料有限公司 | 一种聚酰亚胺材料及其制备方法 |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118878823A (zh) * | 2024-06-17 | 2024-11-01 | 波米科技有限公司 | 一种聚合物a、制备方法及其应用 |
| CN120590629A (zh) * | 2025-08-07 | 2025-09-05 | 武汉柔显科技股份有限公司 | 聚酰亚胺前体、液晶取向剂、液晶取向膜及制造方法、液晶表示元件 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPWO2023219112A1 (ja) | 2023-11-16 |
| CN119212979A (zh) | 2024-12-27 |
| TW202406893A (zh) | 2024-02-16 |
| KR20250009419A (ko) | 2025-01-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7505643B2 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2022234820A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2023219112A1 (ja) | 新規なジアミン化合物、該ジアミンを用いて得られる重合体、液晶配向剤、液晶配向膜、及び液晶表示素子 | |
| JP2024105348A (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2023032753A1 (ja) | 液晶配向剤、液晶配向膜、及び液晶表示素子 | |
| JP7351435B2 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2024157869A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| KR20240023525A (ko) | 액정 배향제, 액정 배향막 및 액정 표시 소자 | |
| WO2023074392A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2023054567A1 (ja) | 液晶配向剤、液晶配向膜、及び液晶表示素子 | |
| WO2025079517A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025164610A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025205803A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| JP2024007369A (ja) | 液晶配向膜の製造方法、液晶表示素子の製造方法、液晶配向膜、及び液晶表示素子 | |
| WO2025105278A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2023210532A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025121249A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025079520A1 (ja) | 液晶配向剤、液晶配向膜、及び液晶表示素子 | |
| TW202534109A (zh) | 液晶配向劑、液晶配向膜及液晶顯示元件 | |
| WO2025121189A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025079518A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025177978A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| WO2025105279A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 | |
| TW202523828A (zh) | 液晶配向劑、液晶配向膜及液晶顯示元件 | |
| WO2024122359A1 (ja) | 液晶配向剤、液晶配向膜及び液晶表示素子 |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 23803587 Country of ref document: EP Kind code of ref document: A1 |
|
| ENP | Entry into the national phase |
Ref document number: 2024520477 Country of ref document: JP Kind code of ref document: A |
|
| WWE | Wipo information: entry into national phase |
Ref document number: 202380040199.8 Country of ref document: CN |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| WWP | Wipo information: published in national office |
Ref document number: 202380040199.8 Country of ref document: CN |
|
| 122 | Ep: pct application non-entry in european phase |
Ref document number: 23803587 Country of ref document: EP Kind code of ref document: A1 |