JP4946149B2 - Composition for anisotropic dye film, anisotropic dye film and polarizing element - Google Patents

Description

  The present invention relates to an anisotropic dye film having a high dichroic ratio useful for a polarizing plate or the like provided in a display element of a light control element, a liquid crystal element (LCD), or an organic electroluminescence element (OLED), and the difference thereof. The present invention relates to an anisotropic dye film composition capable of obtaining an isotropic dye film, and a polarizing element using the anisotropic dye film.

  In the LCD, a linearly polarizing plate or a circularly polarizing plate is used to control optical rotation and birefringence in display. Also in OLED, a circularly polarizing plate is used for preventing reflection of external light. Conventionally, iodine has been widely used as a dichroic material in these polarizing plates (polarizing elements). However, since iodine has a high sublimation property, when it is used in a polarizing element, its heat resistance and light resistance are not sufficient, and the polarization characteristics deteriorate over time.

  Therefore, for example, as described in Patent Document 1 and Non-Patent Documents 1 and 2, a polarizing element using an organic dye as a dichroic substance (dichroic dye) has been studied.

  The dichroic dyes described in these documents form a lyotropic liquid crystal phase in a solvent such as water or alcohol, and can be easily aligned by an external field such as an alignment substrate, a flow field, an electric field, or a magnetic field. . For example, when Brilliant Yellow (CI-364) is used, a positive dichroic dye film can be obtained, and when Methylene Blue (CI-922) or Amaranth (CI-184) is used, a negative dichroic dye film can be obtained. It has been. However, there is a drawback that the resulting dichroic dye film has low dichroism. Although there is a problem that dichroism is lowered due to schlieren defects peculiar to liquid crystals as described in the literature and defects due to drying strain generated during drying, even if the liquid crystals are perfectly aligned, there are still more problems to be solved. It had been.

  Ideally, the alignment axis of the liquid crystal and the absorption axis of the dye are exactly the same for a positive dichroic dye film, while the alignment axis of the liquid crystal is for a negative dichroic dye film. It is desirable that the absorption axis of the dye is completely perpendicular. The alignment axis of the liquid crystal coincides with the average direction of the long axis of the aggregate in the solvent, but it is difficult to make the long axis of the aggregate coincide with the absorption axis of the dye or to be completely perpendicular for the following reasons. .

  As described in Non-Patent Document 3, the main factor that the dye in the solvent associates is due to the interaction between the aromatic rings.

  As described in Non-Patent Documents 4 and 5, such aromatic rings do not pile up vertically due to electrostatic repulsion of π electrons, and it is more stable that they are shifted and stacked. If it is in an aqueous solution, it may become more energetically stable if it is stacked vertically in order to reduce the contact area between the solvent water and the hydrophobic aromatic ring. Such an effect cannot be expected in a sex membrane.

  Therefore, the long axis of the aggregate and the dye molecule surface are not perpendicular or parallel to each other, and an intermediate state is easily obtained. Assuming that the angle between the long axis of the aggregate and the normal of the dye molecule surface is α, a positive dichroic dye film if 45 ° <α ≦ 90 °, and a negative if 0 ° ≦ α <45 °. However, it was difficult for the value of α to be 0 ° or 90 °, and it was normal to take a value between 0 ° and 90 °. As a result, even if polarized light parallel to the orientation axis of the conventional dichroic dye film is incident or perpendicular polarized light is incident, it has finite absorption, so that it is not an ideal dichroic dye film. There wasn't.

  In response to this problem, as described in Non-Patent Document 6, attempts have been made to correct deviations in the association of aromatic rings by blending iodine. There was a problem of having the same drawbacks as the iodine type polarizing plate.

US Patent No. 2400087 "The Fixing of Molecular Orientation", J. F. Dreyer, Physical and Colloid Chemistry, 1948, Vol. 52, p.808 "Light Polarization from Films of Lyotropic Nematic Liquid Crystals", J. F. Dreyer, Journal de Physique, 1969, Vol. 4, p. 114 "Chromonic Liquid Crystal Phases", J. Lydon, Current Opinion in Colloid & Interface Science, 1998, Vol. 3, p.458-466 "The Nature of π-π Interactions", C. A. Hunter, et al., Journal of the American Chemical Society, 1990, Vol.112, p.5525 "Aromatic Interactions", C. A. Hunter, et al., Journal of the Chemical Society, Perkin Transactions 2, 2001, p.651 "Tetra (tert-butyl) phthalocyanine Cooper-Iodine Complex Film with Large Dichroism Induced by Shear", H. Tanaka, et al., Journal of the Chemical Society, Chemical Communications, 1994, p.1851

The present invention has been made to solve such problems.
That is, the present invention uses an anisotropic dye film having a high dichroic ratio, an anisotropic dye film composition capable of obtaining the anisotropic dye film, and the anisotropic dye film. An object is to provide a polarizing element.

  As a result of intensive studies, the present inventors have used a composition containing an electron-deficient discotic compound and an electron-rich compound, or made these compounds anisotropic. It has been found that an anisotropic dye film having a high dichroic ratio can be obtained by incorporating it in the dye film, and the present invention has been achieved.

That is, the first gist of the present invention is an anisotropic dye film composition containing an electron-deficient discotic compound, an electron-rich compound , and a solvent. The solvent is any one selected from the group consisting of water, water-miscible organic solvents, and mixed solvents of water and water-miscible organic solvents, and the electron-deficient (Electron-Deficient ) The discotic compound has a solubility of 0.1% or more with respect to the solvent, and the electron-rich compound is any of 0.1 to 50% with respect to the solvent. It exists in the composition for anisotropic pigment | dye films | membranes for wet film formation characterized by being a compound which forms a lyotropic liquid crystal phase in a density | concentration range (Claim 1).

  Here, it is preferable that the electron-rich compound is a dye.

  In this case, the dye is preferably an azo dye (claim 3).

  In addition, it is preferable that the electron-deficient discotic compound is an aromatic compound or an azaheterocyclic compound.

  Further, it is also preferable that the electron-deficient discotic compound is an azo dye containing an anthraquinone derivative or an anthraquinone derivative as a partial structure.

The second gist of the present invention resides in an anisotropic dye film characterized by being formed using the anisotropic dye film composition according to the first gist described above (claim 6 ). ).

Further , the anisotropic dye film has a ratio YY / YZ of polarization absorption from the following directions (i) and (ii) with respect to CH out-of-plane variable vibration at 800 to 900 cm ^−1: 1. The characteristic is preferably 8 or more (claim 7 ).
(I) Direction that absorbs most visible light (ii) Direction that transmits most visible light

Another aspect of the present invention is characterized by using an anisotropic dye film according to the second aspect described above, it consists in polarizing element (claim 8).

  According to the present invention, a composition containing an electron-deficient discotic compound and an electron-rich compound is used, or these compounds are applied to an anisotropic dye film. By containing it, an anisotropic dye film having a high dichroic ratio can be obtained.

  Hereinafter, the best mode for carrying out the present invention (hereinafter, an embodiment of the present invention) will be described. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

  In the present specification, the term “anisotropic dye film” refers to electromagnetic properties in any two directions selected from a total of three directions in the three-dimensional coordinate system of the dye film thickness direction and any two orthogonal in-plane directions. Is a dye film having anisotropy. Examples of electromagnetic properties include optical properties such as absorption and refraction, and electrical properties such as resistance and capacitance. Examples of the film having optical anisotropy such as absorption and refraction include a linearly polarizing film, a circularly polarizing film, a retardation film, and a conductive anisotropic film. That is, the present invention is preferably used for a polarizing film, a retardation film, and a conductive anisotropic film, and more preferably used for a polarizing film.

[I. Electron-Deficient discotic compound]
First, the electron-deficient discotic compound used for the anisotropic dye film composition and anisotropic dye film of the present invention will be described. In the following description, an electron-deficient discotic compound may be referred to as “an anisotropic dye film material of the present invention” or “a material of the present invention”.

  The “electron-deficient discotic compound” in the present invention also includes a dye having an electron-deficient discotic partial structure. In the following description, an electron-deficient discotic compound may be referred to as “the dye for an anisotropic dye film of the present invention” or “the dye of the present invention”.

[I-1. Electron-deficient discotic compound (material for anisotropic dye film of the present invention)]
In this specification, “electron-deficient discotic compound” means, for example, Reference 1 (“An Electron-Deficient Discotic Liquid-Crystalline Material”, K. Pieterse, et al., Chemistry of Materials, 2001, Vol.13, p.2675), which has a relatively large electron affinity and is preferably larger than benzene, preferably a quadrupole moment Q _{zz of} −20 × 10 ⁻⁴⁰ Cm ² or more. More preferably, it refers to a compound having a disc-like partial structure having a positive quadrupole moment Q _zz . Here, z represents a coordinate axis perpendicular to the molecular plane of the discotic compound.

  The quadrupole moment is a tensor amount expressed by the following volume integration from the charge density ρ at the relative position r = (x, y, z) from the molecular centroid.

If the molecule is axisymmetric with respect to z, such as benzene, it is called a uniaxial quadrupole. Its strength is a scalar quantity Q expressed by the following equation, which is consistent with the zz component Q _{zz of the} tensor quantity.

The electrostatic interaction between the plate-like molecules stacked in the z direction is strongly influenced by the value Q _zz of the zz component. Table 1 below shows Q _zz of typical plate-like molecules. Such a value of the quadrupole moment can be measured by, for example, quantum mechanical calculation described in the following references 2 to 6 or the like, or a method described in the following reference 7 or the like.

Reference 2: "The Molecular Electric Quadrupole Moment and Solid-State Architecture", JH Williams, Acc. Chem. Res., 1993, Vol.26, p.593.
Reference 3: "The electric structure of the azabenzenes an AB initio MO-SCF-LCAO study", J. Almlof et al., J. Electron Spectroscopy and Related Phenomena, 1973, Vol. 2, p. 51.
Reference 4: "Multiple contributions to potentials of mean torque for solutes dissolved in liquid crystal solvents", JW Emsley et al., Liquid Crystals, 1991, Vol. 9, p.649.
Reference 5: "The Molecular Zeeman Effect", DH Sutter, WH Flygare, Topics in Current Chemistry, 1976, Vol. 63, p.89.
Reference 6: "Quadrupole Moment Calculations for Some Aromatic Hydrocarbons", A. Chablo et.al., Chemical Physics Letters, 1981, Vol. 78, p.424.
Reference 7: AD Buckingham, Advances in Chemical Physics, 1967, Vol.12, p.107.

  As shown in Table 1 above, electron-rich (Electron-Rich) discotic compounds such as benzene have a negative quadrupole moment, but lack electrons such as hexafluorobenzene and anthraquinone. It is known that (Electron-Deficient) discotic compounds have a positive quadrupole moment.

  Further, Reference 8 ("Computer Simulation Studies of Anisotropic Systems XXIX. Quadrupolar Gay-Berne Discs and Chemically Induced Liquid Crystal Phases", MA Bates, et al., Liquid Crystals, 1998, Vol. 24 (2), p. 229), it is known that when plate-like compounds having quadrupole moments having different signs approach each other, it is stable to associate with each other without deviation.

  In a compound with a complicated charge distribution, such as a condensed polycyclic compound having a relatively high molecular weight, it is not always accurate to consider the quadrupole moment interaction of these compounds as a whole, but Reference 9 ("Complementary Polytopic Interactions ( CPI) as Revealed by Molecular Modeling using the XED Force Field ", OR Lozman, et al., Journal of the Chemical Society, Perkin Transactions 2, 2001, p.1446). It is thought that it can be considered as the sum of the quadrupole moment interactions.

  As described above, in the present invention, by using an electron-deficient discotic compound as the material for the anisotropic dye film, the electrostatic repulsion of π electrons is suppressed and stacked vertically without deviation. It becomes possible to obtain an aggregate. As a result, the angle α formed between the long axis of the aggregate and the normal plane of the dye molecule surface can be brought close to 0 °, and an ideal dichroic dye film can be obtained.

  Examples of the electron-deficient discotic compound that can be used as the material of the present invention include aromatic compounds or azaheterocyclic compounds having a substituent with high electron affinity.

  Examples of aromatic compounds include benzenes (perfluorobenzene, benzoquinone, cyanobenzene, nitrobenzene, phthalimide, cyanoquinomethane, etc.), naphthalenes (perfluoronaphthalene, naphthoquinone, cyanonaphthalene, nitronaphthalene, cyanonaphthomethane). Etc.), anthracenes (such as anthraquinone), fluorenes (such as nitrofluorenone), and perylenes (such as perylene diimide).

  Examples of azaheterocyclic compounds include pyridine, pyrazine, pyrimidine, 1,3,5-triazine, indole, isoindole, quinoline, isoquinoline, quinoxaline and the like.

  Examples of substituents with high electron affinity include oxo groups, cyano groups, nitro groups, halogen atoms (fluorine atoms, chlorine atoms, etc.), sulfo groups, carboxy groups, sulfo groups, or alkali metals of carboxy groups (sodium, etc.) Examples thereof include salts and alkaline earth metal salts.

  Examples of electron-deficient discotic compounds are derived from aromatic compounds or azaheterocyclic compounds having one or more substituents with high electron affinity exemplified above. Examples thereof include compounds having one or more ring structures.

  An electron-deficient discotic compound has a partial ring structure derived from an aromatic compound or azaheterocyclic compound having one or more substituents with high electron affinity in one molecule. The structure is preferably a compound having 33 mol% or more, more preferably 50 mol% or more.

Here, in the present invention, the mol% of the ring structure (partial structure) in one molecule is calculated from the number of the ring structures in one molecule.
For example, in the case of the following compounds, since one ring structure has one ring structure in one molecule and this one ring structure has a substituent having a high electron affinity, the mol% of the ring structure in one molecule is 100 Mol%.

  In the case of the following compounds, there are three ring structures in one molecule, and two rings (quinoline rings at both ends) are azaheterocyclic compounds, so the mole% of the ring structure in one molecule is 67 mol% (2/3).

  For compounds having different structures and having the same mol% of the ring structure in one molecule, the degree of electron deficiency is further determined by the value of the quadrupole moment.

  In addition, the electron-deficient discotic compound used as the material of the present invention may be a dye.

  In addition, since the material of this invention uses a solvent when manufacturing an anisotropic pigment | dye film | membrane by a wet film-forming method, it is preferable to have a solubility of 0.1% or more with respect to the solvent mentioned later.

  When the electron-deficient discotic compound used as the material of the present invention is a dye, the dye has an electron-deficient discotic partial structure.

  In this specification, the “electron-deficient disc-shaped partial structure” means “I-1. Similar to the “electron-deficient discotic compound” described in the column of “Material for Anisotropic Dye Film of the Present Invention”, it has a relatively large electron affinity and a negative quadrupole moment. It means a partial structure. That is, the dye of the present invention is a dye having such a partial structure in one molecule.

  Examples of electron-deficient disk-shaped partial structures include partial structures derived from the aromatic compounds or azaheterocyclic compounds exemplified above, and substitutions having high electron affinity as exemplified above. Groups and the like.

  Preferred specific examples of an electron-deficient discotic compound (including a dye having an electron-deficient discotic partial structure) that can be used as the material of the present invention are represented by the following formulae. Compounds. However, the electron-deficient discotic compound that can be used as the material of the present invention is not limited to these examples.

  The electron-deficient discotic compound represented by the following formula is exemplified by the free acid type. An electron-deficient discotic compound may be used as it is in the free acid form, or a part of the acid group may be in a salt form. Examples of the salt type include salts of alkali metals such as Na, Li, and K, ammonium salts that may be substituted with alkyl groups or hydroxyalkyl groups, and organic amine salts. Examples of the organic amine include a lower alkyl amine having 1 to 6 carbon atoms, a hydroxy substituted lower alkyl amine having 1 to 6 carbon atoms, a carboxy substituted lower alkyl amine having 1 to 6 carbon atoms, and the like. In the case of these salt types, the type is not limited to one type, and a plurality of types may be mixed.

A compound represented by the following structural formula, wherein A ¹ , B ¹ , B ² and D ¹ are each selected from the following groups.

  Among the above-exemplified compounds, any isomer that causes stereoisomerism such as optical isomerism is included in the exemplification.

  The above compound preferably has a solubility of 1% by weight or more with respect to the solvent described later, and is a compound that forms a lyotropic liquid crystal phase in any concentration range of 1 to 50% by weight. preferable.

  Among the electron-deficient discotic compounds, an azo dye containing an anthraquinone derivative or an anthraquinone derivative as a partial structure is also preferable from the viewpoint of the dichroism of the resulting film.

[II. Anisotropic Dye Film Composition]
The composition for anisotropic dye film of the present invention is a composition used for forming an anisotropic dye film, and is an electron-deficient discotic compound and electron-rich (Electron). -Rich) compound. Furthermore, it usually contains a solvent and, if necessary, other components.

(I) Solvent:
Examples of the solvent include water, a water-miscible organic solvent, a mixed solvent of water and a water-miscible organic solvent, and the like. Specific examples of the organic solvent include alcohols such as methyl alcohol, ethyl alcohol and isopropyl alcohol, glycols such as ethylene glycol and diethylene glycol, and cellosolves such as methyl cellosolve and ethyl cellosolve. Any one of these solvents may be used alone, or two or more thereof may be mixed and used in an arbitrary combination and ratio.

(Ii) Electron-Deficient discotic compounds:
As the electron-deficient discotic compound, the above-mentioned electron-deficient discotic compound is used. Any one of the electron-deficient discotic compounds may be used alone, or two or more thereof may be mixed and used in an arbitrary combination and ratio.

  The ratio of the electron-deficient discotic compound in the composition of the present invention is usually 0.1 parts by weight or more, preferably 0.2 parts by weight or more when the whole composition is 100 parts by weight. Moreover, it is usually 50 parts by weight or less, preferably 40 parts by weight or less. If the proportion of the material of the present invention is below the lower limit of this range, the effect of using an electron-deficient discotic compound may not be obtained, and if it exceeds the upper limit of this range, Since the viscosity as a solution becomes high and it may become difficult to handle, it is not preferable.

(Iii) Electron-Rich compound (dye):
The composition of the present invention contains an electron-rich compound, and this electron-rich compound is usually a dye (hereinafter referred to as “electron-rich ( Electron-Rich) dye ”). Electron-Rich dyes have a relatively small ionization potential and a quadrupole moment Q _zz less than −20 × 10 ⁻⁴⁰ Cm ² as described in Reference 1 above. A pigment containing 50 mol% or more of a disc-like partial structure. The quadrupole moment Q _zz is as described above.

  Examples of electron-rich dyes used in the composition of the present invention include azo dyes, stilbene dyes, cyanine dyes, phthalocyanine dyes, and condensed polycyclic dyes (perylene, oxazine dyes). ) And the like. Of these, azo dyes composed of aromatic hydrocarbons such as benzene and naphthalene substituted with an alkyl group, alkoxy group, sulfone group, amino group or the like, porphyrins, phthalocyanines, and the like are preferable, and azo dyes are particularly preferable.

  Preferred specific examples of the electron-rich dye used in the composition of the present invention include dyes represented by the following formulas (note that these formulas are all shown in free acid form): . However, the electron-rich pigment that can be used in the composition of the present invention is not limited to these examples.

  Among the electron-rich pigments exemplified above, any isomers that produce stereoisomerism such as optical isomerism are included in the examples.

  Any one of the electron-rich pigments exemplified above may be used alone, or two or more of them may be used in combination in any combination and ratio.

  The electron-rich pigment used in the composition of the present invention preferably has a solubility of usually 0.1% or more, particularly 1% or more in the above-mentioned solvent, A compound that forms a lyotropic liquid crystal phase in any concentration range of 0.1 to 50% is preferable.

  The molecular weight of the electron-rich dye is usually 200 or more, particularly 350 or more, and usually 5000 or less, especially 3500 or less in a free state that does not take a salt form from the viewpoint of color tone and production. A range is preferable.

  Electron-rich pigments may be used in the free acid form, or may be those in which some of the acid groups are in the salt form. Further, a salt-type dye and a free acid-type dye may be mixed. Furthermore, when it is obtained in a salt form at the time of production, it may be used as it is, or may be used after being converted into a desired salt form.

  Examples of the salt type include salts of alkali metals such as Na, Li and K, ammonium salts optionally substituted with alkyl groups or hydroxyalkyl groups, and salts of organic amines. Examples of the organic amine include a lower alkyl amine having 1 to 6 carbon atoms, a hydroxy substituted lower alkyl amine having 1 to 6 carbon atoms, a carboxy substituted lower alkyl amine having 1 to 6 carbon atoms, and the like. In the case of these salt types, the type is not limited to one type, and a plurality of types may be mixed.

  The ratio of the electron-rich pigment in the composition of the present invention is usually 50 parts by weight or less, preferably 40 parts by weight or less when the entire composition is 100 parts by weight. If the ratio of the dye exceeds this range, the viscosity of the resulting solution of the composition is increased, which may be difficult to handle.

  The weight fraction of the electron-deficient discotic compound and the electron-rich pigment is usually preferably in the range of 10/90 to 90/10. Outside this range, it is not preferred because the effect of using an electron-deficient discotic compound or an electron-rich pigment may not be obtained.

(Iv) Other ingredients:
The composition of the present invention may contain other components in addition to the above-mentioned solvent, an electron-deficient discotic compound, and an electron-rich pigment.

  For example, when applying the composition of the present invention to a substrate as a dye film-forming solution in a wet film-forming method, which will be described later, in order to improve the wettability and coating properties to the substrate, A surfactant may be added. As the surfactant, any of anionic, cationic, and nonionic surfactants can be used. The concentration of the surfactant in the composition of the present invention is usually preferably 0.05% by weight or more and 0.5% by weight or less.

  In addition, amino acids, hydroxyamines and the like may be used as additives for the purpose of improving the association of the dye and reducing defects in the anisotropic dye film.

  Furthermore, as additives other than those described above, known additives described in Reference Document 10 (“Additives for Coating”, Edited by J. Bieleman, Willey-VCH, 2000) can be used.

  The weight fraction of the electron-deficient site and the electron-rich site in all the components of the composition of the present invention is usually 5/95 or more, preferably 35/65. In addition, it is usually 95/5 or less, preferably 65/35 or less. If it is out of this range, the blending effect of each component may be difficult to appear, which is not preferable.

[III. Anisotropic Dye Film]
In the following description, the anisotropic dye film of the present invention will be described by dividing it into characteristics relating to the composition, characteristics relating to the manufacturing method, and characteristics relating to physical properties. The anisotropic dye film of the present invention preferably satisfies all of these characteristics, but the anisotropic dye film that satisfies any one of these characteristics does not satisfy the other characteristics. Alternatively, even when other characteristics are unknown, it corresponds to the anisotropic dye film of the present invention.

[III-1. Composition of anisotropic dye film]
The anisotropic dye film of the present invention is characterized by containing an electron-deficient discotic compound and an electron-rich compound when focusing on its composition. The electron-deficient discotic compound and the electron-rich compound are as described above. Further, the ratio is not particularly limited.

  The anisotropic dye film of the present invention may further contain other components. As another component, what was illustrated as a component contained in the composition of this invention mentioned above is mentioned.

[III-2. Method for producing anisotropic dye film]
The anisotropic dye film of the present invention is characterized by being formed using the above-described composition for an anisotropic dye film of the present invention (the composition of the present invention) when attention is paid to its production method. Specifically, the anisotropic dye film of the present invention can be produced by forming a film using the above-described composition of the present invention. As the film formation method, either a dry film formation method or a wet film formation method may be used. However, in the case where the composition (aqueous solution) of the present invention used for film formation may exhibit liquid crystallinity, It is preferable to use a wet film formation method.

(I) Dry film forming method:
Examples of the dry film-forming method include a method of producing an unstretched film using the composition of the present invention and a polymer, and stretching the obtained unstretched film. As a method for producing an unstretched film, for example, (a) a method in which a polymer is formed into a film and then dyed using the composition of the present invention, and (b) a solution of the polymer. And a method of forming a film after adding the composition of the present invention to dye the stock solution. The dyeing, film formation and stretching described above can be performed by the general methods described below.

  In the case of the above-mentioned method (a), a polymer film is added to the dyeing bath in which the composition of the present invention and, if necessary, an inorganic salt such as sodium chloride and bow glass, and a dyeing aid such as a surfactant are added. Is soaked and dyed, and then treated with boric acid as necessary and dried. The temperature of the dye bath at the time of immersion is usually 20 ° C. or higher, preferably 30 ° C. or higher, and usually 80 ° C. or lower, preferably 50 ° C. or lower. Moreover, the time of the dyeing bath at the time of immersion is usually 1 minute or more, preferably 3 minutes or more, and usually 60 minutes or less, preferably 20 minutes or less.

  On the other hand, in the case of the above-mentioned method (b), the polymer is dissolved in water and / or a hydrophilic organic solvent such as alcohol, glycerin, dimethylformamide, and the composition of the present invention is added to perform stock solution dyeing. The dyeing stock solution is formed into a film by casting, solution coating, extrusion, or the like to produce a dyed film. The concentration of the polymer to be dissolved in the solvent varies depending on the type of polymer, but is usually 5% by weight or more, preferably about 10% by weight or more, and usually 30% by weight or less, preferably 20% by weight. It is about the following. The concentration of the dye dissolved in the solvent is usually 0.1% by weight or more, preferably about 0.8% by weight or more, usually 5% by weight or less, preferably 2.5% by weight based on the polymer. % Or less.

  The obtained unstretched film is stretched in a uniaxial direction by an appropriate method. By performing the stretching treatment, the dye molecules are oriented and dichroism is expressed. Examples of the uniaxial stretching method include a method of performing tensile stretching by a wet method, a method of performing tensile stretching by a dry method, a method of performing inter-roll compression stretching by a dry method, and the like. May be. The draw ratio is 2 times or more and 9 times or less, but when polyvinyl alcohol and derivatives thereof are used as the polymer, the range of usually 2.5 times or more and 6 times or less is preferable.

  After the stretching and orientation treatment, boric acid treatment is performed for the purpose of improving the water resistance and the degree of polarization of the stretched film. The boric acid treatment improves the light transmittance and the degree of polarization of the anisotropic dye film. The conditions for the boric acid treatment vary depending on the type of the hydrophilic polymer used and the dye, but in general, the boric acid concentration is usually 1% by weight or more, preferably about 5% by weight or more, usually 15%. It is about 10% by weight or less, preferably about 10% by weight or less. Further, the treatment temperature is usually 30 ° C. or higher, preferably 50 ° C. or higher and usually 80 ° C. or lower. When the boric acid concentration is less than 1% by weight or when the treatment temperature is less than 30 ° C., the treatment effect is small, and when the boric acid concentration exceeds 15% by weight or the treatment temperature exceeds 80 ° C. The anisotropic dye film becomes fragile and is not preferable.

  The film thickness of the anisotropic dye film obtained by the dry film-forming method is usually 10 μm or more, preferably 30 μm or more, and usually 200 μm or less, preferably 100 μm or less.

(Ii) Wet deposition method:
On the other hand, as the wet film forming method, various known methods can be used. For example, after preparing the composition of the present invention as a coating solution, it is applied to various substrates such as a glass plate and dried. Examples thereof include a method of obtaining a dye by orientation and lamination.

  Examples of the substrate include glass, triacetate, acrylic, polyester, triacetyl cellulose, and a urethane film. In order to control the orientation direction of the dichroic dye on the surface of the substrate, a known method described in “Liquid Crystal Handbook” (Maruzen Co., Ltd., issued on October 30, 2000), pages 226 to 239, etc. Thus, an alignment treatment layer may be applied.

  When the wet film-forming method is used, the concentration of the dye in the composition of the present invention is usually 0.1% by weight or more, particularly 1% by weight or more, and usually 50% by weight or less, especially 30% by weight or less. It is preferable. If the dye concentration is too low, sufficient dichroism cannot be obtained, and if it is too high, film formation may be difficult.

  Examples of coating methods include Yuji Harasaki's “Coating Engineering” (Asakura Shoten Co., Ltd., published on March 20, 1971), pages 253-277, “Creation and Application of Molecular Cooperative Materials” supervised by Kunihiro Ichimura (see MC Publishing, published on March 3, 1998) The publicly known methods described on pages 118 to 149, and spin coating, spray coating, bar coating, and roll coating on a substrate that has been previously subjected to orientation treatment. And a coating method using a blade coating method. The temperature during application is usually preferably 0 ° C. or more and 80 ° C. or less, and the humidity is usually preferably 10% RH or more and 80% RH or less.

  The temperature during drying of the coating film is preferably 0 ° C. or more and 120 ° C. or less, and the humidity is preferably about 10% RH or more and 80% RH or less.

  When an anisotropic dye film is formed on a substrate by a wet film forming method, the thickness of the anisotropic dye film obtained after drying is usually 50 nm or more, especially 100 nm or more, and usually 50 μm or less, especially 20 μm. Hereinafter, the range of 1 μm or less is more preferable.

(Iii) Protective layer:
The anisotropic dye film of the present invention obtained by the dry film forming method or the wet film forming method described above is used with a protective layer provided if necessary. This protective layer is formed by lamination on the anisotropic dye film of the present invention with a transparent polymer film such as triacetate, acrylic, polyester, polyimide, triacetylcellulose, or urethane film, and is practically used. Provided.

[III-3. Properties of anisotropic dye film]
The anisotropic dye film of the present invention is characterized by satisfying at least one of the following (a) and (b) when attention is paid to its physical properties.

(A) Ratio of polarized light absorption from the following two directions (i) and (ii) with respect to SO ₃ stretching vibration in the vicinity of 970 cm ⁻¹ (hereinafter sometimes referred to as “ratio of polarized light absorption from two directions”) The tilt angle obtained from the above is 10 ° or less.
(B) The value of the ratio YY / YZ of polarized light absorption from the following two directions (i) and (ii) with respect to the CH out-of-plane variable vibration at 800 to 900 cm ⁻¹ is 1.8 or more.
(I) Direction that absorbs most visible light (ii) Direction that transmits most visible light

  The physical properties of (a) and (b) can be measured as follows.

(A) Tilt angle obtained from the ratio of polarized light absorption from two directions to SO ₃ stretching vibration near 970 cm ⁻¹ :
A direction parallel to the film surface of the anisotropic dye film and absorbing most visible light is defined as an X direction, and a direction transmitting the most visible light is defined as a Y direction.
The peak intensity of 970 cm ^-1 vicinity of the infrared absorption spectrum obtained by infrared light polarized in the X-direction and perpendicularly incident on the film surface and Ax, vertically incident infrared light polarized in the Y direction to the film plane When the peak intensity in the vicinity of 970 cm ^{−1 of the} infrared absorption spectrum obtained as described above is Ay, the tilt angle is calculated by the following equation.

(B) Value of the ratio YY / YZ of polarized light absorption from two directions with respect to the CH out-of-plane variable vibration at 800 to 900 cm ⁻¹ :
A direction parallel to the film surface of the anisotropic dye film and absorbing most visible light is defined as an X direction, and a direction transmitting the most visible light is defined as a Y direction.
In an infrared absorption spectrum obtained by injecting infrared light polarized in the Y direction at an angle of 60 ° in the X direction, a CH out-of-plane bending vibration peak seen in the region of 800 to 900 cm ⁻¹ is obtained by the Lorentzian method. When the peaks are separated into n peaks, the intensity of each peak is YYi (i = 1 to n).
Similarly, in an infrared absorption spectrum obtained by injecting infrared light polarized in the Y direction at an angle of 60 ° in the Y direction, a CH out-of-plane variable vibration peak seen in the region of 800 to 900 cm ⁻¹ is obtained. When the peaks are separated into n peaks by the Lorentzian method, each peak intensity is set to YZi (i = 1 to n).
Here, the peak position and the peak inverse value width of YYi and YZi are set to be the same.
From the obtained YYi (i = 1 to n) and YZi (i = 1 to n), the YY / YZ ratio is calculated by the following equation.

[IV. Polarizing element]
The polarizing element of the present invention uses the above-described anisotropic dye film of the present invention. Specifically, when the anisotropic dye film of the present invention forms a polarizing filter or the like of various display elements such as LCDs and OLEDs, the present invention directly applies to the electrode substrate constituting these display elements. The base material on which the anisotropic dye film of the present invention or the anisotropic dye film of the present invention is formed may be used as a constituent member of these display elements.

  The anisotropic dye film of the present invention uses a light absorption anisotropy and functions as a polarizing film for obtaining linearly polarized light, circularly polarized light, elliptically polarized light, etc., and also includes a film forming process and a composition containing a substrate and a dye. By selecting an object, it can be functionalized as various anisotropic films such as refractive anisotropy and conduction anisotropy, and a polarizing element that can be used in various types and various applications can be obtained.

  The polarizing element of the present invention uses the above-described anisotropic dye film of the present invention. When the anisotropic dye film of the present invention is formed on a substrate to form the polarizing element of the present invention, The formed anisotropic dye film itself may be used. In addition to the protective layer as described above, an adhesive layer or an antireflection layer, an alignment film, a function as a retardation film, and a function as a brightness enhancement film. Layers with various functions such as a function as a reflection film, a function as a transflective film, a layer with optical functions such as a diffusion film, etc. are laminated by a wet film formation method and used as a laminate May be.

These layers having optical functions can be formed, for example, by the following method.
The layer having a function as a retardation film is subjected to, for example, a stretching process described in Japanese Patent No. 2841377, Japanese Patent No. 3094113, or a process described in Japanese Patent No. 3168850. Can be formed.

  The layer having a function as a brightness enhancement film may be formed by forming a fine hole by a method as described in, for example, Japanese Patent Application Laid-Open Nos. 2002-169025 and 2003-29030, or the center of selective reflection. It can be formed by overlapping two or more cholesteric liquid crystal layers having different wavelengths.

The layer having a function as a reflective film or a transflective film can be formed using a metal thin film obtained by vapor deposition or sputtering.
The layer having a function as a diffusion film can be formed by coating the protective layer with a resin solution containing fine particles.

  The layer having a function as a retardation film or an optical compensation film can be formed by applying and aligning a liquid crystal compound such as a discotic liquid crystal compound or a nematic liquid crystal compound.

EXAMPLES Next, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example, unless the summary is exceeded.
In the following description, “part” means “part by weight”.

In each of the following Examples and Comparative Examples, the dichroic ratio of the anisotropic dye film is determined after measuring the transmittance of the anisotropic dye film with a spectrophotometer in which an iodine polarizing element is arranged in the incident optical system. The following formula was used for calculation.
Dichroic ratio (D) = Az / Ay
Az = -log (Tz)
Ay = -log (Ty)
Tz: transmittance for polarized light in the direction of the absorption axis of the anisotropic dye film Ty: transmittance for polarized light in the direction of the polarization axis of the anisotropic dye film

Further, the tilt angle obtained from the ratio of the polarization absorption from two directions to the SO ₃ stretching vibration near 970 cm ⁻¹ and the polarization absorption from two directions to the CH out-of-plane variable vibration at 800 to 900 cm ⁻¹ . The value of the ratio YY / YZ is the above [III-3. The physical properties of the anisotropic dye film] were determined. Here, the infrared absorption spectrum of the anisotropic dye film was measured by NEXUS670 manufactured by Thermo Electron.

[Example 1]
To 72 parts of water, 25 parts of a lithium salt of a dye represented by the following formula (I-1) and 3 parts of an electron-deficient discotic compound represented by the following formula (II-1) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. On a glass substrate (75 mm × 25 mm, 1.1 mm thickness, about 80 nm polyimide alignment film previously rubbed with a cloth) with a polyimide alignment film formed on the surface by spin coating, An anisotropic dye film (the anisotropic dye film of the present invention) is obtained by applying the above composition for anisotropic dye film with an applicator (manufactured by Imoto Seisakusho Co., Ltd.) having a gap of 5 μm and then naturally drying. It was.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Example 2]
To 69 parts of water, 30 parts of a lithium salt of the dye represented by the above formula (I-1) and 1 part of an electron-deficient discotic compound represented by the following formula (II-2) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Example 3]
To 69 parts of water, 30 parts of a lithium salt of a dye represented by the above formula (I-1) and 1 part of an electron-deficient discotic compound represented by the following formula (II-3) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Example 4]
To 69 parts of water, 30 parts of a lithium salt of the dye represented by the above formula (I-1) and 1 part of an electron-deficient discotic compound represented by the following formula (II-4) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 with an applicator having a gap of 5 μm (manufactured by Imoto Seisakusho Co., Ltd.) and then naturally dried to obtain an anisotropic dye film (of the present invention). An anisotropic dye film) was obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Example 5]
To 66 parts of water, 33 parts of a lithium salt of a dye represented by the above formula (I-1) and 1 part of an electron-deficient discotic compound represented by the following formula (II-5) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was coated on the same substrate as in Example 1 by the same method as in Example 4, and then naturally dried to obtain an anisotropic dye film (anisotropy of the present invention). Dye film) was obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Example 6]
1. 70.3 parts of water, 27 parts of a lithium salt of the dye represented by the above formula (I-1), and an electron-deficient discotic compound represented by the following formula (II-6) After adding 7 parts and stirring and dissolving, it filtered and the insoluble content was removed, and the composition for anisotropic dye films | membranes (composition of this invention) was obtained. This anisotropic dye film composition was coated on the same substrate as in Example 1 by the same method as in Example 4, and then naturally dried to obtain an anisotropic dye film (anisotropy of the present invention). Dye film) was obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 1]
After adding 37 parts of the lithium salt of the dye represented by the above formula (I-1) to 63 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye films of Examples 1-6.

[Example 7]
To 82 parts of water, 16 parts of a sodium salt of a dye represented by the following formula (I-2) and 2 parts of an electron-deficient discotic compound represented by the following formula (II-7) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 with an applicator having a gap of 10 μm (manufactured by Imoto Seisakusho Co., Ltd.), and then naturally dried to obtain an anisotropic dye film (of the present invention). An anisotropic dye film) was obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 2]
After adding 15 parts of the sodium salt of the dye represented by the above formula (I-2) to 85 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 7.

[Example 8]
To 75 parts of water, 24 parts of a lithium salt of a dye represented by the following formula (I-3) and 1 part of an electron-deficient discotic compound represented by the following formula (II-8) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 3]
After adding 20 parts of lithium salt of the dye represented by the above formula (I-3) to 80 parts of water, without adding an electron-deficient discotic compound, stirring and dissolving The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 8.

[Example 9]
To 79 parts of water, 20 parts of a lithium salt of a dye represented by the following formula (I-4) and 1 part of an electron-deficient discotic compound represented by the following formula (II-9) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

The tilt angle obtained from the ratio of polarized light absorption from two directions with respect to SO ₃ stretching vibration in the vicinity of 970 cm ⁻¹ is 7.54 degrees, and the two directions against CH out-of-plane variable vibration at 800 to 900 cm ^−1. The value of the ratio YY / YZ of polarized light absorption from was 1.85.

[Comparative Example 4]
After adding 20 parts of the lithium salt of the dye represented by the above formula (I-4) to 80 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 9.

The tilt angle obtained from the ratio of polarized light absorption from two directions with respect to SO ₃ stretching vibration in the vicinity of 970 cm ⁻¹ is 11.65 degrees, and the two directions with respect to CH out-of-plane variable angular vibration at 800 to 900 cm ^−1. The value of the ratio YY / YZ of polarized light absorption from was 1.77.

[Example 10]
To 84 parts of water, 15 parts of a lithium salt of a dye represented by the following formula (I-5) and 1 part of an electron-deficient discotic compound represented by the following formula (II-10) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 5]
After adding 15 parts of the lithium salt of the dye represented by the above formula (I-5) to 85 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 2 below. The anisotropic dye film of this comparative example had only a lower dichroic ratio (light absorption anisotropy) than the anisotropic dye film of Example 10.

[Example 11]
To 81 parts of water, 18 parts of a lithium salt of a dye represented by the following formula (I-6) and 1 part of an electron-deficient discotic compound represented by the following formula (II-11) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

Further, the tilt angle obtained from the ratio of polarized light absorption from two directions with respect to SO ₃ stretching vibration near 970 cm ⁻¹ is 9.56 degrees, and the two directions against CH out-of-plane variable angular vibration at 800 to 900 cm ^−1. The value of the ratio YY / YZ of polarized light absorption from 1.90 was 1.92.

[Comparative Example 6]
Only by adding 16 parts of the lithium salt of the dye represented by the above formula (I-6) to 84 parts of water, stirring is performed without adding an electron-deficient discotic compound (material of the present invention). After being dissolved, the composition for anisotropic dye film was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 11.

[Example 12]
To 81 parts of water, 18 parts of a lithium salt of a dye represented by the following formula (I-7) and 1 part of an electron-deficient discotic compound represented by the following formula (II-12) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

Further, the tilt angle obtained from the ratio of polarized light absorption from two directions with respect to SO ₃ stretching vibration near 970 cm ⁻¹ is 9.72 degrees, and the two directions against CH out-of-plane variable angular vibration at 800 to 900 cm ⁻¹ The value of the polarization absorption ratio YY / YZ from was 1.94.

[Comparative Example 7]
Only by adding 16 parts of a lithium salt of the dye represented by the above formula (I-7) to 84 parts of water, stirring is performed without adding an electron-deficient discotic compound (material of the present invention). After being dissolved, the composition for anisotropic dye film was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 12.

[Example 13]
To 84 parts of water, 15 parts of a lithium salt of a dye represented by the following formula (I-8) and 1 part of an electron-deficient discotic compound represented by the following formula (II-13) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 8]
After adding 14 parts of the lithium salt of the dye represented by the above formula (I-8) to 86 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 13.

[Example 14]
To 70 parts of water, 24 parts of a lithium salt of a dye represented by the following formula (I-9) and 6 parts of an electron-deficient discotic compound represented by the following formula (II-14) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 9]
After adding 35 parts of lithium salt of the dye represented by the above formula (I-9) to 65 parts of water, without adding an electron-deficient discotic compound, stirring and dissolving The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 14.

[Example 15]
To 80 parts of water, 12 parts of a lithium salt of a dye represented by the following formula (I-10) and 8 parts of an electron-deficient discotic compound represented by the following formula (II-15) were added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 10]
After adding 35 parts of lithium salt of the dye represented by the above formula (I-10) to 65 parts of water, without adding an electron-deficient discotic compound, stirring and dissolving The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 15.

[Example 16]
In 80 parts of water, 10.4 parts of a lithium salt of a dye represented by the following formula (I-11) and an electron-deficient discotic compound 9.6 represented by the following formula (II-16) After adding a part and stirring and dissolving, it filtered and the insoluble content was removed and the composition for anisotropic dye films | membranes (composition of this invention) was obtained. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 11]
After adding 20 parts of lithium salt of the dye represented by the above formula (I-11) to 80 parts of water, without adding an electron-deficient discotic compound, stirring and dissolving The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a low dichroic ratio (light absorption anisotropy) compared to the anisotropic dye film of Example 16.

[Example 17]
In 75 parts of water, 13 parts of a lithium salt of a dye represented by the following formula (I-12) and an electron-deficient discotic compound represented by the following formula (II-17) (material of the present invention) ) After adding 12 parts and stirring to dissolve, the composition was filtered to remove insolubles, thereby obtaining an anisotropic dye film composition (the composition of the present invention). This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 12]
After adding 35 parts of lithium salt of the dye represented by the above formula (I-12) to 65 parts of water, without adding an electron-deficient discotic compound, stirring and dissolving The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a lower dichroic ratio (light absorption anisotropy) than the anisotropic dye film of Example 17.

[Example 18]
To 80 parts of water, 10 parts of a lithium salt of a dye represented by the following formula (I-13) and 10 parts of an electron-deficient discotic compound represented by the following formula (II-18) are added, After stirring and dissolving, the composition for anisotropic dye film (the composition of the present invention) was obtained by filtering to remove insoluble matter. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 13]
After adding 20 parts of the lithium salt of the dye represented by the above formula (I-13) to 80 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a lower dichroic ratio (light absorption anisotropy) than the anisotropic dye film of Example 18.

[Example 19]
In 80 parts of water, 10.4 parts of a lithium salt of a dye represented by the following formula (I-14) and an electron-deficient discotic compound 9.6 represented by the following formula (II-19) After adding a part and stirring and dissolving, it filtered and the insoluble content was removed and the composition for anisotropic dye films | membranes (composition of this invention) was obtained. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film (an anisotropic dye film of the present invention). Obtained.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this example had a high dichroic ratio (light absorption anisotropy) that can function sufficiently as a polarizing film.

[Comparative Example 14]
After adding 20 parts of the lithium salt of the dye represented by the above formula (I-14) to 80 parts of water, without adding an electron-deficient discotic compound, the mixture was stirred and dissolved. The composition for anisotropic dye films was obtained by filtering and removing an insoluble content. This anisotropic dye film composition was applied to the same substrate as in Example 1 by the same method, and then naturally dried to obtain an anisotropic dye film.

  With respect to the obtained anisotropic dye film, the maximum absorption wavelength (λmax) and the dichroic ratio (D) were measured. The results are shown in Table 3 below. The anisotropic dye film of this comparative example had only a lower dichroic ratio (light absorption anisotropy) than the anisotropic dye film of Example 19.

  The anisotropic dye film of the present invention can be used as a polarizing film for obtaining linearly polarized light, circularly polarized light, elliptically polarized light and the like by utilizing the anisotropy of light absorption. In addition, the process of forming a dye film and the selection of a composition containing a base material and a dye enable functionalization as various anisotropic films such as refractive anisotropy and conduction anisotropy. It can be set as the polarizing element which can be used for.

Claims (8)

An anisotropic dye film composition comprising an electron-deficient discotic compound, an electron-rich compound , and a solvent ,
The solvent is any one selected from the group consisting of water, a water-miscible organic solvent, and a mixed solvent of water and a water-miscible organic solvent,
The electron-deficient discotic compound has a solubility of 0.1% or more in the solvent,
The electron-rich compound is a compound that forms a lyotropic liquid crystal phase in any concentration range of 0.1 to 50% with respect to the solvent . An anisotropic dye film composition for wet film formation. 2. The composition for anisotropic dye film according to claim 1, wherein the electron-rich compound is a dye. 3. The composition for anisotropic dye film according to claim 2, wherein the dye is an azo dye. The anisotropy according to any one of claims 1 to 3, wherein the electron-deficient discotic compound is an aromatic compound or an azaheterocyclic compound. A composition for a dye film. The said electron deficient (Electron-Deficient) discotic compound is an azo pigment | dye which contains an anthraquinone derivative or an anthraquinone derivative as a partial structure, The difference as described in any one of Claims 1-3 characterized by the above-mentioned. An isotropic dye film composition . An anisotropic dye film formed using the composition for anisotropic dye film according to any one of claims 1 to 5 . Claims ratio YY / YZ of the values of polarization absorption from the direction of the following for CH out-of-plane bending vibration in 800~900cm ^-1 (i) and (ii) is characterized in that at least 1.8 6. An anisotropic dye film according to 6 .
(I) Direction that absorbs most visible light (ii) Direction that transmits most visible light A polarizing element using the anisotropic dye film according to claim 6 .