Polarized light-emitting film, polarized light-emitting plate, and display device

Abstract

To provide a polarized light-emitting film which exhibits the maximum polarized light emission wavelength in the visible light region, in particular in a 550-780 nm region, and offers high durability in harsh environments, and to provide a polarized light-emitting plate and a display device.SOLUTION: A polarized light-emitting film is provided, containing a water-soluble chromenopyridin-7-on compound represented by a formula (1) below or a salt thereof. In the formula (1), Q represents an arbitrary substituent group, R1 and R2 each represent a C1-4 alkyl group that may have an arbitrary substituent group, and X represents a cyano group or a carbamoyl group, and n represents an integer of 1 or 2.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a polarized light emitting film, a polarized light emitting plate, and a display device.

Background Art

[0002] A polarizing plate having a light transmission / blocking function is a basic component of a display device such as a liquid crystal display (LCD) together with a liquid crystal having a light switching function. The application fields of this LCD are expanding from small devices such as calculators and watches in the early days to notebook computers, word processors, liquid crystal projectors, liquid crystal TVs, car navigation systems, and indoor and outdoor measuring instruments. In addition, it can also be applied to lenses having a polarizing function. For example, it has been applied to sunglasses with improved visibility and polarizing glasses corresponding to 3D TVs in recent years. Thus, with the wide spread of the uses of polarizing plates, their use conditions have also become wide-ranging, such as from low temperature to high temperature, from low humidity to high humidity, and from low light quantity to high light quantity. Therefore, a polarizing plate having high polarizing performance and high durability is required.

[0003] Generally, a polarizing film constituting a polarizing plate is manufactured by stretching and orienting a film of polyvinyl alcohol or its derivative containing iodine or a dichroic dye, or by generating polyene by dehydrochlorination of a polyvinyl chloride film or dehydration of a polyvinyl alcohol-based film and orienting it. Since a polarizing plate composed of such a conventional polarizing film uses a dichroic dye having a light absorption effect in the visible light region, the transmittance in the visible light region decreases. For example, the transmittance of a commercially available general polarizing plate in the visible light region is 35 to 45%. When a polarizing plate with a low transmittance in the visible light region is used for a display or the like, the transmittance of the entire display decreases. Therefore, methods for obtaining polarization without using a conventional polarizing plate have been studied. As such methods, Patent Documents 1 to 3 disclose techniques for emitting polarized light. However, these techniques use special metals with high rarity value, such as lanthanoid metals like europium (Eu) and terbium (Tb), as materials having an action of emitting polarized light (hereinafter also referred to as "polarized light emission action"), and are very difficult to manufacture, so they are not suitable for mass production. Furthermore, since the emission of polarized light is weak, it is difficult to apply them to displays. Therefore, it is desired to develop a new material that exhibits a polarized light emission action without using a conventional polarizing plate, has high visible light transmittance, has high emission intensity and polarization degree in the visible light region, and can be applied to liquid crystal displays and the like that require durability in harsh environments.

[0004] So far, as a polarized light emitting film that does not use special metals with high rarity value, for example, Patent Document 4 describes a blue to blue-green polarized light emitting film using a stilbene-based water-soluble dichroic compound. Patent Document 5 also describes a green emitting film using a coumarin-based water-soluble dichroic compound. Thus, at present, blue to green polarized light emitting films and polarized light emitting plates have been actively developed.

[0005] As a polarized light emitting film having long-wavelength emission, a perylene-based polarized light emitting film described in Patent Document 6 has been developed. This patent describes a polarized light emitting film having maximum polarized light emission at 545 nm.

[0006] Generally, compounds having chromenopyridin-7-one as a partial structure take advantage of the characteristics of low solubility and high durability due to their high planarity, and have been previously used mainly as oil-soluble colorants for clothes, resins, etc., such as disperse dyes, as described in Patent Documents 7 to 11.

[0007] In addition, active development has also been carried out for other applications. For example, for dyes for optical recording media, they are described in Patent Documents 12 to 13; for dyes for solar cells, they are described in Patent Documents 14 to 15; for retroreflective sheets, they are described in Patent Document 16; and for the development related to organic EL elements, they are described in Patent Documents 17 to 19.

[0008] As described above, although compounds having chromenopyridin-7-one as a partial structure have been applied and developed in various applications mainly as oil-soluble materials by taking advantage of their coloring performance and light-emitting performance, there are no examples related to applications regarding polarization or polarization luminescent materials.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

[0010] An object of the present invention is to provide a polarized light emitting film, a polarized light emitting plate, and a display device that have a maximum polarized light emission wavelength in the visible light region, particularly in the region of 550 to 780 nm, and have high durability in a harsh environment. [Means for Solving the Problems]

[0011] The present inventors have found that a specific water-soluble chromenopyridine-7-one compound or a salt thereof exhibits a polarized light emission action in the visible light region, particularly in the red-orange to pink region, when irradiated with light in the ultraviolet to visible region, for example, light of 300 to 600 nm. Further, it has been found that a polarized light emitting film and a polarized light emitting plate containing such a compound or a salt thereof exhibit excellent durability even in a harsh environment. The present invention has been completed based on these findings.

[0012] That is, the present invention relates to the following [1] to [6]. [1] A polarized light emitting film containing a water-soluble chromenopyridin-7-one compound represented by the following formula (1) or a salt thereof.

[0013] [Chemical formula]

[0014] (In formula (1), Q represents an arbitrary substituent, and R 1 and R 2 are each an optionally substituted C1-4 alkyl group, X is a cyano group or a carbamoyl group, and n represents an integer of 1 or 2.) [2] The polarized light emitting film according to [1], wherein the water-soluble chromenopyridin-7-one compound or a salt thereof is represented by the following formula (2).

[0015] [Chemical formula]

[0016] (In formula (2), R 1 and R 2 are each an optionally substituted C1-4 alkyl group, and X represents a cyano group or a carbamoyl group.) [3] The polarized light emitting film according to [1] or [2], including a substrate. [4] The polarized light emitting film according to [3], wherein the substrate is made of a polyvinyl alcohol resin or a derivative thereof. [5] The polarized light emitting film according to any one of [1] to [4], containing one or more organic dyes or fluorescent dyes other than the water-soluble chromenopyridin-7-one compound or a salt thereof. [6] A polarized light emitting plate including the polarized light emitting film according to [5] and a transparent protective layer provided on at least one surface thereof. [7] A display device comprising the polarized light emitting film described in [5] or the polarized light emitting plate described in [6].

Effects of the Invention

[0017] The polarized light emitting film and the polarized light emitting plate containing the water-soluble chromenopyridine-7-one compound having a specific structure of the present invention or a salt thereof have a maximum polarized light emission wavelength particularly in the region of 550 to 780 nm and have high durability under harsh environments, and are therefore useful for display devices.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited by the embodiments shown below. Hereinafter, the numerical range represented by “~” means a range including the numerical values described before and after “~” as the lower limit value and the upper limit value. Also, unless otherwise specified, the compounds represented by the respective formulas and the compounds shown in each compound example are represented in the form of the free acid (state where no salt is formed), but the salts thereof are also included in the technical scope of the present invention. Also, unless otherwise specified, for the sake of convenience, the description of “water-soluble chromenopyridine-7-one compound or a salt thereof” may be simply abbreviated as “water-soluble chromenopyridine-7-one compound”. When the number of carbon atoms is, for example, 1 to 4, it may be abbreviated as C1-4.

[0020] [Chromenopyridine-7-one compound] The water-soluble chromenopyridin-7-one compound according to an embodiment of the present invention is represented by the following formula (1).

[0021] [Chemical formula]

[0022] (In formula (1), Q represents an arbitrary substituent, and R 1 and R 2 are each an optionally substituted C1-4 alkyl group, X is a cyano group or a carbamoyl group, and n represents an integer of 1 or 2.)

[0023] In the above formula (1), R 1 and R 2 are each an optionally substituted C1-4 alkyl group. Examples of the C1-4 alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a t-butyl group.

[0024] In the above formula (1), Q, and R 1 and R 2Examples of optional substituents that may be present include, for example, heterocyclic amino groups, condensed heterocyclic amino groups, alkoxy groups, aryloxy groups, alkylcarbonylamino groups, arylcarbonylamino groups, alkylcarbonyloxy groups, arylcarbonyloxy groups, alkylcarbonyl groups, arylcarbonyl groups, alkylcarbamoyl groups, arylcarbamoyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, alkylsulfonylamino groups, arylsulfonylamino groups, alkylsulfamoyl groups, arylsulfamoyl groups, alkylsulfonyl groups, arylsulfonyl groups, alkylthio groups, arylthio groups, alkylureido groups, arylureido groups, alkoxycarbonylamino groups, aryloxycarbonylamino groups, alkylamino groups, arylamino groups, hydroxy group (-OH), cyano group (-CN), nitro group (-NO2), mercapto group (-SH), halogen atoms, and the like. Preferably, they are alkoxy groups, aryloxy groups, alkylcarbonylamino groups, arylcarbonylamino groups, alkylcarbamoyl groups, arylcarbamoyl groups, alkylsulfonylamino groups, arylsulfonylamino groups, alkylsulfamoyl groups, arylsulfamoyl groups, alkylthio groups, arylthio groups, alkylamino groups, arylamino groups, nitro group (-NO2), and halogen atoms.

[0025] Examples of the above heterocyclic amino groups include 5- or 6-membered heterocyclic amino groups containing 1 to 3 heteroatoms selected from the group consisting of nitrogen atoms, oxygen atoms, and sulfur atoms. Specific examples of such heterocyclic amino groups include, for example, 5-membered heterocyclic aliphatic amino groups such as pyrrolidinylamino, tetrahydrofurylamino, tetrahydrothiophen-2-ylamino, tetrahydrothiophen-3-ylamino; 6-membered heterocyclic aliphatic amino groups such as piperidinylamino, piperazinylamino, dioxan-2-ylamino, morpholinylamino, thiomorpholinylamino; 5-membered aromatic heterocyclic amino groups such as pyrrole amino, pyrazole amino, imidazole amino, triazole amino, furyl amino, thiophen-2-yl amino, thiophen-3-yl amino, oxazole amino, thiazole amino; or, 6-membered aromatic heterocyclic amino groups such as pyridyl amino, pyrazyl amino, pyridazinyl amino, triazinyl amino, etc. may be mentioned. It is preferable that the heterocyclic group has an aromatic ring as the heterocyclic moiety. Further, the heteroatom constituting the heterocyclic ring is preferably selected from a nitrogen atom and a sulfur atom.

[0026] Examples of the condensed heterocyclic amino group include a condensed 5- or 6-membered heterocyclic amino group in which one benzene ring is condensed to a 5- or 6-membered heterocyclic group containing 1 to 3 heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom, and a sulfur atom. Specific examples of such a condensed heterocyclic amino group include, for example, a condensed heterocyclic alicyclic amino group having a 5-membered alicyclic heterocyclic moiety such as phthalanyl amino; a condensed heterocyclic alicyclic amino group having a 6-membered alicyclic heterocyclic moiety such as benzopyranyl amino; condensed aromatic heterocyclic amino groups having an aromatic 5-membered ring as the heterocyclic moiety such as benzpyrrole amino, benzpyrazole amino, benzimidazole amino, benzotriazole amino, benzofuranyl amino, benzothiophen-2-yl amino, benzothiophen-3-yl amino, benzoxazole amino, benzothiazole amino; or, condensed aromatic heterocyclic amino groups having an aromatic 6-membered ring as the heterocyclic moiety such as quinolinyl amino, cinnolinyl amino, phthalazinyl amino, quinazolinyl amino, quinoxalinyl amino, etc. may be mentioned. It is preferable that the heterocyclic group has an aromatic ring as the heterocyclic moiety. Further, the heteroatom constituting the heterocyclic ring is preferably selected from a nitrogen atom and a sulfur atom.

[0027] Examples of the alkoxy group include linear, branched or cyclic alkoxy groups, preferably C1-10 alkoxy groups. Specific examples of the C1-10 alkoxy group include, for example, linear C1-10 alkoxy groups such as methoxy, ethoxy, n-propoxy, n-butoxy, n-pentoxy, n-hexyloxy, n-heptyloxy, n-octyloxy, n-nonyloxy, n-decyloxy; branched C3-10 alkoxy groups such as isopropoxy, isobutoxy, sec-butoxy, t-butoxy, isoamyloxy, t-amyloxy, isohexyloxy, t-hexyloxy, isoheptyloxy, t-heptyloxy, isooctyloxy, t-octyloxy, 2-ethylhexyloxy, isononyloxy, isodecyloxy; or cyclic C3-7 alkoxy groups such as cyclopropoxy, cyclobutoxy, cyclopentoxy, cyclohexyloxy, cycloheptyloxy. Among these, linear or branched alkoxy groups are preferred.

[0028] The aryloxy group is preferably a C6-12 aryloxy group, and specific examples include, for example, phenoxy, naphthyloxy, biphenyloxy and the like.

[0029] Examples of the alkylcarbonylamino group include linear, branched or cyclic alkylcarbonylamino groups, preferably C1-10 alkylcarbonylamino groups. Specific examples of the C1-10 alkylcarbonylamino group include, for example, linear C1-10 alkylcarbonylamino groups such as methylcarbonylamino, ethylcarbonylamino, n-propylcarbonylamino, n-butylcarbonylamino, n-pentylcarbonylamino, n-hexylcarbonylamino, n-heptylcarbonylamino, n-octylcarbonylamino, n-nonylcarbonylamino, n-decylcarbonylamino; Isopropylcarbonylamino, isobutylcarbonylamino, sec-butylcarbonylamino, t-butylcarbonylamino, isoamylcarbonylamino, t-amylcarbonylamino, isohexylcarbonylamino, t-hexylcarbonylamino, isoheptylcarbonylamino, t-heptylcarbonylamino, isooctylcarbonylamino, t-octylcarbonylamino, 2-ethylhexylcarbonylamino, isononylcarbonylamino, isodecylcarbonylamino and other branched C3-10 alkylcarbonylamino groups; or Cyclopropylcarbonylamino, cyclobutylcarbonylamino, cyclopentylcarbonylamino, cyclohexylcarbonylamino, cycloheptylcarbonylamino and other cyclic C3-7 alkylcarbonylamino groups. Among these, linear or branched alkylcarbonylamino groups are preferred, and linear alkylcarbonylamino groups are more preferred.

[0030] The above arylcarbonylamino group is preferably a C6-12 arylcarbonylamino group. Specific examples include, for example, phenylcarbonylamino, naphthylcarbonylamino, biphenylcarbonylamino and the like.

[0031] The above alkylcarbonyloxy group includes linear, branched or cyclic alkylcarbonyloxy groups, preferably C1-10 alkylcarbonyloxy groups. Specific examples of the C1-10 alkylcarbonyloxy group include, for example, Linear C1-10 alkylcarbonyloxy groups such as methylcarbonyloxy, ethylcarbonyloxy, n-propylcarbonyloxy, n-butylcarbonyloxy, n-pentylcarbonyloxy, n-hexylcarbonyloxy, n-heptylcarbonyloxy, n-octylcarbonyloxy, n-nonylcarbonyloxy, n-decylcarbonyloxy; Isopropylcarbonyloxy, isobutylcarbonyloxy, sec-butylcarbonyloxy, t-butylcarbonyloxy, isoamylcarbonyloxy, t-amylcarbonyloxy, isohexylcarbonyloxy, t-hexylcarbonyloxy, isoheptylcarbonyloxy, t-heptylcarbonyloxy, isooctylcarbonyloxy, t-octylcarbonyloxy, 2-ethylhexylcarbonyloxy, isononylcarbonyloxy, isodecylcarbonyloxy and other branched C3-10 alkylcarbonyloxy groups; or, Cyclopropylcarbonyloxy, cyclobutylcarbonyloxy, cyclopentylcarbonyloxy, cyclohexylcarbonyloxy, cycloheptylcarbonyloxy and other cyclic C3-7 alkylcarbonyloxy groups can be mentioned. Among these, linear or branched alkylcarbonyloxy groups are preferred, and linear alkylcarbonyloxy groups are more preferred.

[0032] The above arylcarbonyloxy group is preferably a C6-12 arylcarbonyloxy group, and specific examples include, for example, phenylcarbonyloxy, naphthylcarbonyloxy, biphenylcarbonyloxy and the like.

[0033] The above alkylcarbonyl group includes linear, branched or cyclic alkylcarbonyl groups, preferably C1-10 alkylcarbonyl groups. Specific examples of C1-10 alkylcarbonyl groups include, for example, Linear C1-10 alkylcarbonyl groups such as methylcarbonyl, ethylcarbonyl, n-propylcarbonyl, n-butylcarbonyl, n-pentylcarbonyl, n-hexylcarbonyl, n-heptylcarbonyl, n-octylcarbonyl, n-nonylcarbonyl, n-decylcarbonyl; Branched C3-10 alkylcarbonyl groups such as isopropylcarbonyl, isobutylcarbonyl, sec-butylcarbonyl, t-butylcarbonyl, isoamylcarbonyl, t-amylcarbonyl, isohexylcarbonyl, t-hexylcarbonyl, isoheptylcarbonyl, t-heptylcarbonyl, isooctylcarbonyl, t-octylcarbonyl, 2-ethylhexylcarbonyl, isononylcarbonyl, isodecylcarbonyl; or, Cyclic C3-7 alkylcarbonyl groups such as cyclopropylcarbonyl, cyclobutylcarbonyl, cyclopentylcarbonyl, cyclohexylcarbonyl, cycloheptylcarbonyl. Among these, linear or branched alkylcarbonyl groups are preferred, and linear alkylcarbonyl groups are more preferred.

[0034] The above arylcarbonyl group is preferably a C6-12 arylcarbonyl group, and specific examples include, for example, phenylcarbonyl (benzoyl), naphthylcarbonyl, biphenylcarbonyl, and the like.

[0035] The above alkylcarbamoyl group includes linear, branched or cyclic monoalkylcarbamoyl groups or dialkylcarbamoyl groups. The monoalkylcarbamoyl group is preferably a mono C1-10 alkylcarbamoyl group, and specific examples include, for example, Linear mono C1-10 alkylcarbamoyl groups such as methylcarbamoyl, ethylcarbamoyl, n-propylcarbamoyl, n-butylcarbamoyl, n-pentylcarbamoyl, n-hexylcarbamoyl, n-heptylcarbamoyl, n-octylcarbamoyl, n-nonylcarbamoyl, n-decylcarbamoyl; Branched mono-C3-10 alkylcarbamoyl groups such as isopropylcarbamoyl, isobutylcarbamoyl, sec-butylcarbamoyl, t-butylcarbamoyl, isoamylcarbamoyl, t-amylcarbamoyl, isohexylcarbamoyl, t-hexylcarbamoyl, isoheptylcarbamoyl, t-heptylcarbamoyl, isooctylcarbamoyl, t-octylcarbamoyl, 2-ethylhexylcarbamoyl, isononylcarbamoyl, isodecylcarbamoyl, etc.; or, Cyclic mono-C3-7 alkylcarbamoyl groups such as cyclopropylcarbamoyl, cyclobutylcarbamoyl, cyclopentylcarbamoyl, cyclohexylcarbamoyl, cycloheptylcarbamoyl, etc. Among these, linear or branched monoalkylcarbamoyl groups are preferred, and linear monoalkylcarbamoyl groups are more preferred.

[0036] The dialkylcarbamoyl group is preferably a di-C1-10 alkylcarbamoyl group. Specific examples include, for example, Linear di-C1-10 alkylcarbamoyl groups such as dimethylcarbamoyl, diethylcarbamoyl, di-n-propylcarbamoyl, di-n-butylcarbamoyl, di-n-pentylcarbamoyl, di-n-hexylcarbamoyl, di-n-heptylcarbamoyl, di-n-octylcarbamoyl, di-n-nonylcarbamoyl, di-n-decylcarbamoyl; Branched di-C3-10 alkylcarbamoyl groups having two branched chains such as diisopropylcarbamoyl, diisobutylcarbamoyl, di-sec-butylcarbamoyl, di-t-butylcarbamoyl, diisoamylcarbamoyl, di-t-amylcarbamoyl, diisohexylcarbamoyl, di-t-hexylcarbamoyl, diisoheptylcarbamoyl, di-t-heptylcarbamoyl, diisooctylcarbamoyl, di-t-octylcarbamoyl, di-(2-ethylhexyl)carbamoyl, diisononylcarbamoyl, diisodecylcarbamoyl, etc.; or, Examples of the cyclic diC3-7 alkylcarbamoyl group having two rings include dicyclopropylcarbamoyl, dicyclobutylcarbamoyl, dicyclopentylcarbamoyl, dicyclohexylcarbamoyl, dicycloheptylcarbamoyl and the like. Among these, linear or branched dialkylcarbamoyl groups are preferred, and linear dialkylcarbamoyl groups are more preferred.

[0037] Examples of the arylcarbamoyl group include monoarylcarbamoyl groups or diarylcarbamoyl groups. The monoarylcarbamoyl group is preferably a monoC6-12 arylcarbamoyl group, and specific examples include, for example, phenylcarbamoyl, naphthylcarbamoyl, biphenylcarbamoyl and the like.

[0038] Examples of the diarylcarbamoyl group include preferably diC6-12 arylcarbamoyl groups, and specific examples include, for example, diphenylcarbamoyl, dinaphthylcarbamoyl, di(biphenyl)carbamoyl and the like.

[0039] Examples of the alkoxycarbonyl group include linear, branched or cyclic alkoxycarbonyl groups, preferably C1-10 alkoxycarbonyl groups. Specific examples of the C1-10 alkoxycarbonyl group include for example, linear C1-C10 alkoxycarbonyl groups such as methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, n-butoxycarbonyl, n-pentoxycarbonyl, n-hexyloxycarbonyl, n-heptyloxycarbonyl, n-octyloxycarbonyl, n-nonyloxycarbonyl, n-decyloxycarbonyl; Branched C3-10 alkoxycarbonyl groups such as isopropoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl, t-butoxycarbonyl, isoamyloxycarbonyl, t-amyloxycarbonyl, isohexyloxycarbonyl, t-hexyloxycarbonyl, isoheptyloxycarbonyl, t-heptyloxycarbonyl, isooctyloxycarbonyl, t-octyloxycarbonyl, 2-ethylhexyloxycarbonyl, isononyloxycarbonyl, isodecyloxycarbonyl; or, Cyclic C3-7 alkoxycarbonyl groups such as cyclopropoxycarbonyl, cyclobutoxycarbonyl, cyclopentoxycarbonyl, cyclohexyloxycarbonyl, cycloheptyloxycarbonyl. Among these, linear or branched alkoxycarbonyl groups are preferred, and linear alkoxycarbonyl groups are more preferred.

[0040] The aryl oxycarbonyl group is preferably a C6-12 aryl oxycarbonyl group. Specific examples include, for example, phenoxycarbonyl, naphthyloxycarbonyl, biphenyloxycarbonyl, etc.

[0041] The alkylsulfonylamino group includes linear, branched or cyclic alkylsulfonylamino groups, preferably C1-10 alkylsulfonylamino groups. Specific examples of C1-10 alkylsulfonylamino groups include, for example, Linear C1-10 alkylsulfonylamino groups such as methylsulfonylamino, ethylsulfonylamino, n-propylsulfonylamino, n-butylsulfonylamino, n-pentylsulfonylamino, n-hexylsulfonylamino, n-heptylsulfonylamino, n-octylsulfonylamino, n-nonylsulfonylamino, n-decylsulfonylamino; Isopropylsulfonylamino, isobutylsulfonylamino, sec-butylsulfonylamino, t-butylsulfonylamino, isoamylsulfonylamino, t-amylsulfonylamino, isohexylsulfonylamino, t-hexylsulfonylamino, isoheptylsulfonylamino, t-heptylsulfonylamino, isooctylsulfonylamino, t-octylsulfonylamino, 2-ethylhexylsulfonylamino, isononylsulfonylamino, isodecylsulfonylamino and other branched C3-10 alkylsulfonylamino groups; or, Cyclopropylsulfonylamino, cyclobutylsulfonylamino, cyclopentylsulfonylamino, cyclohexylsulfonylamino, cycloheptylsulfonylamino and other cyclic C3-7 alkylsulfonylamino groups. Among these, linear or branched alkylsulfonylamino groups are preferred, and linear alkylsulfonylamino groups are more preferred.

[0042] The above arylsulfonylamino group is preferably a C6-12 arylsulfonylamino group. Specific examples include, for example, phenylsulfonylamino, toluenesulfonylamino, naphthylsulfonylamino, biphenylsulfonylamino and the like.

[0043] The above alkylsulfamoyl group includes linear, branched or cyclic monoalkylsulfamoyl groups or dialkylsulfamoyl groups. The monoalkylsulfamoyl group is preferably a mono C1-10 alkylsulfamoyl group. Specific examples include, for example, Linear mono C1-10 alkylsulfamoyl groups such as methylsulfamoyl, ethylsulfamoyl, n-propylsulfamoyl, n-butylsulfamoyl, n-pentylsulfamoyl, n-hexylsulfamoyl, n-heptylsulfamoyl, n-octylsulfamoyl, n-nonylsulfamoyl, n-decylsulfamoyl; Branched mono-C3-10 alkylsulfamoyl groups such as isopropylsulfamoyl, isobutylsulfamoyl, sec-butylsulfamoyl, t-butylsulfamoyl, isoamylsulfamoyl, t-amylsulfamoyl, isohexylsulfamoyl, t-hexylsulfamoyl, isoheptylsulfamoyl, t-heptylsulfamoyl, isooctylsulfamoyl, t-octylsulfamoyl, 2-ethylhexylsulfamoyl, isononylsulfamoyl, isodecylsulfamoyl; or, Cyclic mono-C3-7 alkylsulfamoyl groups such as cyclopropylsulfamoyl, cyclobutylsulfamoyl, cyclopentylsulfamoyl, cyclohexylsulfamoyl, cycloheptylsulfamoyl. Among these, linear or branched monoalkylsulfamoyl groups are preferred, and linear monoalkylsulfamoyl groups are more preferred.

[0044] The dialkylsulfamoyl group is preferably a di-C1-10 alkylsulfamoyl group. Specific examples include, for example, Linear di-C1-10 alkylsulfamoyl groups such as dimethylsulfamoyl, diethylsulfamoyl, di-n-propylsulfamoyl, di-n-butylsulfamoyl, di-n-pentylsulfamoyl, di-n-hexylsulfamoyl, di-n-heptylsulfamoyl, di-n-octylsulfamoyl, di-n-nonylsulfamoyl, di-n-decylsulfamoyl; Branched di-C3-10 alkylsulfamoyl groups having two branches such as diisopropylsulfamoyl, diisobutylsulfamoyl, di-sec-butylsulfamoyl, di-t-butylsulfamoyl, diisoamylsulfamoyl, di-t-amylsulfamoyl, diisohexylsulfamoyl, di-t-hexylsulfamoyl, diisoheptylsulfamoyl, di-t-heptylsulfamoyl, diisooctylsulfamoyl, di-t-octylsulfamoyl, di-(2-ethylhexyl)sulfamoyl, diisononylsulfamoyl, diisodecylsulfamoyl; or, Cyclic di-C3-7 alkylsulfamoyl groups having two rings such as dicyclopropylsulfamoyl, dicyclobutylsulfamoyl, dicyclopentylsulfamoyl, dicyclohexylsulfamoyl, dicycloheptylsulfamoyl and the like can be mentioned. Among these, linear or branched dialkylsulfamoyl groups are preferred, and linear dialkylsulfamoyl groups are more preferred.

[0045] Examples of the arylsulfamoyl group include a monoarylsulfamoyl group or a diarylsulfamoyl group. The monoarylsulfamoyl group is preferably a mono-C6-12 arylsulfamoyl group, and specific examples include, for example, phenylsulfamoyl, naphthylsulfamoyl, biphenylsulfamoyl and the like.

[0046] The diarylsulfamoyl group is preferably a di-C6-12 arylsulfamoyl group, and specific examples include, for example, diphenylsulfamoyl, dinaphthylsulfamoyl, di(biphenyl)sulfamoyl and the like.

[0047] Examples of the alkylsulfonyl group include linear, branched or cyclic alkylsulfonyl groups, preferably C1-12 alkylsulfonyl groups. Specific examples of the C1-12 alkylsulfonyl group include, for example, linear C1-12 alkylsulfonyl groups such as methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, n-butylsulfonyl, n-pentylsulfonyl, n-hexylsulfonyl, n-heptylsulfonyl, n-octylsulfonyl, n-nonylsulfonyl, n-decylsulfonyl, n-undecylsulfonyl, n-dodecylsulfonyl; Branched C3-12 alkylsulfonyl groups such as isopropylsulfonyl, isobutylsulfonyl, sec-butylsulfonyl, t-butylsulfonyl, isoamylsulfonyl, t-amylsulfonyl, isohexylsulfonyl, t-hexylsulfonyl, isoheptylsulfonyl, t-heptylsulfonyl, isooctylsulfonyl, t-octylsulfonyl, 2-ethylhexylsulfonyl, isononylsulfonyl, isodecylsulfonyl, isoundecylsulfonyl, t-undecylsulfonyl, isododecylsulfonyl, t-dodecylsulfonyl; or, Cyclic C3-7 alkylsulfonyl groups such as cyclopropylsulfonyl, cyclobutylsulfonyl, cyclopentylsulfonyl, cyclohexylsulfonyl, cycloheptylsulfonyl. Among these, linear or branched alkylsulfonyl groups are preferred, and linear alkylsulfonyl groups are more preferred.

[0048] The above arylsulfonyl group is preferably a C6-12 arylsulfonyl group, and specific examples include, for example, phenylsulfonyl, naphthylsulfonyl, biphenylsulfonyl, etc.

[0049] The above alkylthio group includes linear, branched or cyclic alkylthio groups, preferably C1-10 alkylthio groups. Specific examples of C1-10 alkylthio groups include, for example, Linear C1-10 alkylthio groups such as methylthio, ethylthio, n-propylthio, n-butylthio, n-pentylthio, n-hexylthio, n-heptylthio, n-octylthio, n-nonylthio, n-decylthio; Branched C3-10 alkylthio groups such as isopropylthio, isobutylthio, sec-butylthio, t-butylthio, isoamylthio, t-amylthio, isohexylthio, t-hexylthio, isoheptylthio, t-heptylthio, isooctylthio, t-octylthio, 2-ethylhexylthio, isononylthio, isodecylthio; or, Examples of the cyclic C3-7 alkylthio group include cyclopropylthio, cyclobutylthio, cyclopentylthio, cyclohexylthio, cycloheptylthio, and the like. Among these, linear or branched alkylthio groups are preferred, and linear alkylthio groups are more preferred.

[0050] The arylthio group is preferably a C6-12 arylthio group, and specific examples include phenylthio, naphthylthio, biphenylthio, and the like.

[0051] Examples of the alkylureido group include linear, branched, or cyclic monoalkylureido groups or dialkylureido groups. The monoalkylureido group is preferably a mono C1-10 alkylureido group, and specific examples include, for example, linear mono C1-10 alkylureido groups such as methylureido, ethylureido, n-propylureido, n-butylureido, n-pentylureido, n-hexylureido, n-heptylureido, n-octylureido, n-nonylureido, n-decylureido; branched mono C3-10 alkylureido groups such as isopropylureido, isobutylureido, sec-butylureido, t-butylureido, isoamylureido, t-amylureido, isohexylureido, t-hexylureido, isoheptylureido, t-heptylureido, isooctylureido, t-octylureido, 2-ethylhexylureido, isononylureido, isodecylureido; or cyclic mono C3-7 alkylureido groups such as cyclopropylureido, cyclobutylureido, cyclopentylureido, cyclohexylureido, cycloheptylureido, and the like. Among these, linear or branched alkylureido groups are preferred, and linear alkylureido groups are included.

[0052] The dialkylureido group is preferably a di C1-10 alkylureido group, and specific examples include, for example, Linear diC1-10 alkylureido groups such as dimethylureido, diethylureido, di-n-propylureido, di-n-butylureido, di-n-pentylureido, di-n-hexylureido, di-n-heptylureido, di-n-octylureido, di-n-nonylureido, di-n-decylureido; Branched-chain diC3-C10 alkylureido groups having two branched chains such as diisopropylureido, diisobutylureido, di-sec-butylureido, di-t-butylureido, diisoamylureido, di-t-amylureido, diisohexylureido, di-t-hexylureido, diisoheptylureido, di-t-heptylureido, diisooctylureido, di-t-octylureido, di-(2-ethylhexyl)ureido, diisononylureido, diisodecylureido; or, Cyclic diC3-7 alkylureido groups having two rings such as dicyclopropylureido, dicyclobutylureido, dicyclopentylureido, dicyclohexylureido, dicycloheptylureido. Among these, linear or branched-chain dialkylureido groups are preferred, and linear dialkylureido groups are more preferred.

[0053] Examples of the arylureido group include monoarylureido groups or diarylureido groups. The monoarylureido group is preferably a monoC6-12 arylureido group, and specific examples include, for example, phenylureido, naphthylureido, biphenylureido, etc.

[0054] The diarylureido group is preferably a diC6-12 arylureido group, and specific examples include, for example, diphenylureido, dinaphthylureido, di(biphenyl)ureido, etc.

[0055] Examples of the alkoxycarbonylamino group include linear, branched-chain or cyclic alkoxycarbonylamino groups, preferably C1-10 alkoxycarbonylamino groups. Specific examples of the C1-C10 alkoxycarbonylamino group include, for example, Linear C1-10 alkoxycarbonylamino groups such as methoxycarbonylamino, ethoxycarbonylamino, n-propoxycarbonylamino, n-butoxycarbonylamino, n-pentoxycarbonylamino, n-hexyloxycarbonylamino, n-heptyloxycarbonylamino, n-octyloxycarbonylamino, n-nonyloxycarbonylamino, n-decyloxycarbonylamino; Branched C3-10 alkoxycarbonylamino groups such as isopropoxycarbonylamino, isobutoxycarbonylamino, sec-butoxycarbonylamino, t-butoxycarbonylamino, isoamyloxycarbonylamino, t-amyloxycarbonylamino, isohexyloxycarbonylamino, t-hexyloxycarbonylamino, isoheptyloxycarbonylamino, t-heptyloxycarbonylamino, isooctyloxycarbonylamino, t-octyloxycarbonylamino, 2-ethylhexyloxycarbonylamino, isononyloxycarbonylamino, isodecyloxycarbonylamino; or, Cyclic C3-7 alkoxycarbonylamino groups such as cyclopropoxycarbonylamino, cyclobutoxycarbonylamino, cyclopentoxycarbonylamino, cyclohexyloxycarbonylamino, cycloheptyloxycarbonylamino. Among these, linear or branched alkoxycarbonylamino groups are preferred, and linear alkoxycarbonylamino groups are more preferred.

[0056] The above aryl-oxycarbonylamino group is preferably a C6-12 aryl-oxycarbonylamino group, and specific examples include, for example, phenylcarbonylamino, naphthylcarbonylamino, biphenylcarbonylamino and the like.

[0057] The above alkylamino group includes linear, branched or cyclic monoalkylamino groups or dialkylamino groups. The monoalkylamino group is preferably a mono C1-10 alkylamino group, and specific examples include, for example, Linear mono-C1-10 alkylamino groups such as methylamino, ethylamino, n-propylamino, n-butylamino, n-pentylamino, n-hexylamino, n-heptylamino, n-octylamino, n-nonylamino, and n-decylamino; Branched mono-C3-10 alkylamino groups having two branched chains such as isopropylamino, isobutylamino, sec-butylamino, t-butylamino, isoamylamino, t-amylamino, isohexylamino, t-hexylamino, isoheptylamino, t-heptylamino, isooctylamino, t-octylamino, 2-ethylhexylamino, isononylamino, and isodecylamino; or, Cyclic mono-C3-7 alkylamino groups such as cyclopropylamino, cyclobutylamino, cyclopentylamino, cyclohexylamino, and cycloheptylamino. Among these, linear or branched monoalkylamino groups are preferred, and linear monoalkylamino groups are more preferred.

[0058] The dialkylamino group is preferably a di-C1-10 alkylamino group. Specific examples include, for example, Linear di-C1-10 alkylamino groups such as dimethylamino, diethylamino, di-n-propylamino, di-n-butylamino, di-n-pentylamino, di-n-hexylamino, di-n-heptylamino, di-n-octylamino, di-n-nonylamino, and di-n-decylamino; Branched-chain di-C3-10 alkylamino groups having two branched chains such as diisopropylamino, diisobutylamino, di-sec-butylamino, di-t-butylamino, diisoamylamino, di-t-amylamino, diisohexylamino, di-t-hexylamino, diisoheptylamino, di-t-heptylamino, diisooctylamino, di-t-octylamino, di-(2-ethylhexyl)amino, diisononylamino, and diisodecylamino; or, Examples of the cyclic diC3-7 alkylamino group having two rings include dicyclopropylamino, dicyclobutylamino, dicyclopentylamino, dicyclohexylamino, dicycloheptylamino, and the like. Among these, a linear or branched dialkylamino group is preferred, and a linear dialkylamino group is more preferred.

[0059] Examples of the arylamino group include a monoarylamino group or a diarylamino group. The monoarylamino group is preferably a monoC6-12 arylamino group, and specific examples include, for example, phenylamino (anilino), naphthylamino, biphenylamino, and the like.

[0060] The diarylamino group is preferably a diC6-12 arylamino group, and specific examples include, for example, diphenylamino, dinaphthylamino, di(biphenyl)amino, and the like.

[0061] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and a fluorine atom, a chlorine atom, or a bromine atom is preferred.

[0062] R 1 and R 2 may form a ring. Further, R 1 and R 2 may form a ring through a heteroatom, for example, a nitrogen atom or an oxygen atom.

[0063] In formula (1), X is a cyano group or a carbamoyl group, and a carbamoyl group is preferred.

[0064] In formula (1), n represents an integer of 1 or 2, and 1 is preferred.

[0065] The water-soluble chromenopyridine-7-one compound represented by the above formula (1) or a salt thereof is preferably a compound represented by the following formula (2), or a salt thereof.

[0066]

Chemical formula

[0067] In the above formula (2), R 1 and R 2 are each an optionally substituted C1-4 alkyl group. The C1-4 alkyl group is preferably unsubstituted. R 1 and R 2 are both preferably a methyl group, an ethyl group, an n-propyl group, or an n-butyl group, and more preferably an ethyl group. X represents a cyano group or a carbamoyl group, and is preferably a carbamoyl group.

[0068] Specific examples of the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or a salt thereof are given below. The water-soluble chromenopyridine-7-one compound is represented in the form of the free acid.

[0069]

Chemical formula

[0070]

Chemical formula

[0071]

Chemical formula

[0072] The salt of the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) means a state in which the free acid of the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) forms a salt with an inorganic cation or an organic cation. Examples of the inorganic cation include cations of alkali metals such as lithium, sodium, and potassium, or ammonium (NH4 + ), etc. Examples of the organic cation include, for example, organic ammonium represented by the following formula (3), etc.

[0073] [Chemical formula]

[0074] In formula (3), Z1 to Z4 each independently represent a hydrogen atom, an alkyl group, a hydroxyalkyl group or a hydroxyalkoxyalkyl group, and at least one of Z1 to Z4 is a group other than a hydrogen atom.

[0075] In formula (3), specific examples of Z1 to Z4 include, for example, C1-6 alkyl groups such as methyl, ethyl, butyl, pentyl, hexyl, preferably C1-4 alkyl groups; HydroxyC1-6 alkyl groups such as hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 4-hydroxybutyl, 3-hydroxybutyl, 2-hydroxybutyl, preferably hydroxyC1-4 alkyl groups; or HydroxyC1-6 alkoxyC1-6 alkyl groups such as hydroxyethoxymethyl, 2-hydroxyethoxyethyl, 3-hydroxyethoxypropyl, 3-hydroxyethoxybutyl, 2-hydroxyethoxybutyl, preferably hydroxyC1-4 alkoxyC1-4 alkyl groups and the like.

[0076] Among these inorganic cations or organic cations, cations such as sodium, potassium, lithium, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, ammonium are more preferable, and inorganic cations of lithium, ammonium or sodium are particularly preferable.

[0077] As described above, the water-soluble chromenopyridin-7-one compound represented by formula (1) or (2) according to the embodiment of the present invention has at least one chromenopyridin-7-one skeleton in the molecule and does not have an azo bond. Since the water-soluble chromenopyridin-7-one compound has a chromenopyridin-7-one skeleton, it exhibits a light-emitting action upon irradiation with ultraviolet light, visible light, particularly light in the range of 300 to 600 nm. On the other hand, since the water-soluble chromenopyridin-7-one compound does not have an azo bond in the molecule, the absorption of light caused by the azo bond is suppressed. Due to such a specific structure, these water-soluble chromenopyridin-7-one compounds can absorb ultraviolet light or visible light and utilize the energy thereof to exhibit a light-emitting action of polarized light in the visible light region. Therefore, by using such a water-soluble chromenopyridin-7-one compound or a salt thereof, it is possible to provide a novel polarized light-emitting film and a polarized light-emitting plate having a polarization function in the ultraviolet to visible light region and exhibiting a polarized light-emitting action in the visible light region without using rare and highly valuable lanthanoid metals or the like.

[0078] Next, a method for synthesizing the above-described water-soluble chromenopyridin-7-one compound will be described. Although there are no particular limitations, for example, a water-soluble chromenopyridin-7-one compound represented by formula (1) or (2) can be synthesized by performing the synthetic reaction shown below.

[0079] The water-soluble chromenopyridin-7-one compound represented by the above formula (1) or (2) or a salt thereof can be produced according to a known sulfonation method. Also, regarding the introduction of substituents, for example, it can be synthesized by the methods described in JP-A-57-003860, JP-A-57-031958, and JP-A-49-077939. The compound to be sulfonated is a water-insoluble chromenopyridin-7-one compound having a chromenopyridin-7-one skeleton and may have the above-described substituents. A commercially available compound may be used, or it may be synthesized according to a known method.

[0080] [Polarized Light-Emitting Film] The present invention also includes a polarized light emitting film containing the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) or a salt thereof. In a preferred embodiment of the present invention, the polarized light emitting film includes a substrate containing the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) or a salt thereof. Such a substrate is preferably a film obtained by forming a hydrophilic polymer capable of adsorbing the water-soluble chromenopyridine-7-one compound or a salt thereof. The hydrophilic polymer is not particularly limited, and examples thereof include polyvinyl alcohol-based resins, amylose-based resins, starch-based resins, cellulose-based resins, and polyacrylate-based resins. Among such resins, from the viewpoints of adsorbability, processability, orientation, etc. of dyes such as water-soluble chromenopyridine-7-one compounds, it is preferably a polyvinyl alcohol-based resin or a derivative thereof. As the polyvinyl alcohol-based resin derivative, any one generally known in this technical field can be used. Without being limited thereto, for example, modified polyvinyl alcohol-based resins copolymerized with unsaturated carboxylic acids such as crotonic acid, acrylic acid, methacrylic acid, maleic acid, or unsaturated sulfonic acids, or olefins such as ethylene and propylene can be used. The shape of the substrate is not particularly limited, and it can be produced in any shape such as film shape, sheet shape, flat plate shape, curved plate shape, and hemispherical shape. Further, the thickness of the substrate is usually 10 μm to 100 μm, preferably 20 μm to 80 μm. The substrate may contain the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) or a salt thereof alone or in plural.

[0081] In the above-mentioned polarized luminescent film, the blending ratio of the water-soluble chromenopyridine-7-one compound or its salt contained in the substrate is adjusted to be within a preferable range described later, but is not particularly limited. The polarization performance of the polarized luminescent film varies depending on not only the blending ratio of the water-soluble chromenopyridine-7-one compound contained in the polarized luminescent film, but also various factors such as the swelling degree of the substrate that adsorbs the compound, the stretching ratio, the dyeing time, the dyeing temperature, the pH during dyeing, and the influence of salts. Therefore, the blending ratio of the water-soluble chromenopyridine-7-one compound contained in the polarized luminescent film can be determined according to the swelling degree of the substrate, the temperature, time, pH during dyeing, the type of salt, the concentration of salt, and further the stretching ratio. Such adjustment of the blending ratio can be appropriately adjusted based on the description below.

[0082] The above-mentioned polarized luminescent film may further contain one or more organic dyes or fluorescent dyes other than the water-soluble chromenopyridine-7-one compound or its salt represented by the above formula (1) or (2) for the purpose of adjusting the transmittance, emission color, etc. within a range that does not inhibit the polarized luminescent function of the polarized luminescent film. The other organic dyes or fluorescent dyes used in combination are not particularly limited, but dyes having high dichroism or emission luminance and having little influence on the polarized luminescent function of the polarized luminescent film containing the compound represented by the formula (1) or (2) are preferable. Such other organic dyes include, for example, C.I.Direct.Yellow12, C.I.Direct.Yellow28, C.I.Direct.Yellow44, C.I.Direct.Orange26, C.I.Direct.Orange39, C.I.Direct.Orange71, C.I.Direct.Orange107, C.I.Direct.Red2, C.I.Direct.Red31, C.I.Direct.Red79, C.I.Direct.Red81, C.I.Direct.Red247, C.I.Direct.Blue69, C.I.Direct.Blue78, C.I.Direct.Green80, and C.I.Direct.Green59. These other organic dyes may be in the form of free acids, alkali metal salts (e.g., Na salts, K salts, and Li salts), ammonium salts, or salts of amines.

[0083] When incorporating the above other organic dyes or fluorescent dyes, depending on the application, such as a polarized light emitting film with a neutral gray hue of the desired polarized light emitting film, a polarized light emitting film having a polarization function at a specific wavelength (for example, a color polarized light emitting film for a liquid crystal projector), or other color polarized light emitting films used in sunglasses, etc., the types of dyes to be blended are different. Therefore, the blending ratio of other organic dyes is not particularly limited, but generally, based on 1 part by mass of the water-soluble chromenopyridin-7-one compound represented by the above formula (1) or (2), it is preferable to contain a total of at least one or more of these dyes in the range of 0.01 to 10 parts by mass.

[0084] <Method for manufacturing a polarized light emitting film> The method for manufacturing the above polarized light emitting film will be described. The method for manufacturing the polarized light emitting film according to the present invention is not limited to the following manufacturing methods, but mainly includes a step of preparing a substrate, a step of immersing the substrate in a swelling liquid and stretching the substrate by swelling, a step of impregnating the swollen substrate with a dyeing solution containing at least one water-soluble chromenopyridin-7-one compound represented by the above formula (1) or (2) or a salt thereof, and optionally other organic dyes or fluorescent dyes (hereinafter sometimes collectively referred to as "polarization dyes") to adsorb the polarization dyes on the substrate, a step of immersing the adsorbed substrate in a solution containing a crosslinking agent to stabilize the polarization dyes in the substrate, a stretching step of uniaxially stretching the substrate on which the polarization dyes are adsorbed and crosslinked with the crosslinking agent in a certain direction and arranging them in a certain direction, a washing step of washing the stretched substrate with a washing liquid as necessary, and a drying step of drying the washed substrate.

[0085] (Preparation of substrate) Prepare a substrate for containing the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) or a salt thereof, and optionally another organic dye or fluorescent dye. The substrate may be, for example, a film made of a commercially available polyvinyl alcohol-based resin or a derivative thereof, or may be produced by forming a film of a polyvinyl alcohol-based resin. The method for forming a film of the polyvinyl alcohol-based resin is not particularly limited, and for example, a method of melt-extruding hydrated polyvinyl alcohol, a casting film-forming method, a wet film-forming method, a gel film-forming method (after once cooling and gelling an aqueous polyvinyl alcohol solution, extracting and removing the solvent), a cast film-forming method (pouring an aqueous polyvinyl alcohol solution onto a substrate and drying), and a method by a combination thereof, etc., known film-forming methods can be adopted.

[0086] (Swelling step) Next, the above-mentioned substrate is subjected to a swelling treatment. The swelling treatment is preferably carried out by immersing the substrate in a swelling liquid at 20 to 50 °C for 30 seconds to 10 minutes, and the swelling liquid is preferably water. The stretching ratio of the substrate by the swelling liquid is preferably adjusted to 1.00 to 1.50 times, and more preferably adjusted to 1.10 to 1.35 times.

[0087] (Polarizing dye adsorption / impregnation step) Subsequently, at least one polarizing dye containing the water-soluble chromenopyridine-7-one compound or a salt thereof is adsorbed and impregnated into the substrate obtained by performing the swelling treatment as described above. The implementation of this step is not particularly limited as long as it is a method for adsorbing and impregnating the polarizing dye into the substrate. For example, it is preferable to immerse the substrate in a dyeing solution (dying aqueous solution) containing the polarizing dye. Also, it can be adsorbed by applying the dyeing solution to the substrate. The concentration of the polarizing dye in the dyeing solution only needs to ensure sufficient adsorption of the polarizing dye in the substrate and is not particularly limited. For example, it is preferably 0.0001 to 3% by mass in the dyeing solution, and more preferably 0.001 to 1% by mass.

[0088] In the polarization dye adsorption / impregnation step, the temperature of the above-described dyeing solution is preferably 5 to 80°C, more preferably 20 to 50°C, and particularly preferably 40 to 50°C. Also, the time for immersing the substrate in the dyeing solution can be appropriately adjusted, and it is preferably adjusted within the range of 30 seconds to 20 minutes, and more preferably within the range of 1 to 10 minutes.

[0089] As the polarization dye contained in the above-described dyeing solution, the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) or a salt thereof may be used alone or in combination of two or more. Since the water-soluble chromenopyridine-7-one compound represented by the above formula (1) or (2) or a salt thereof has different emission colors, by containing two or more of these compounds in the substrate, the resulting emission color can be appropriately adjusted to a desired color. Further, if necessary, the dyeing solution may further contain one or more of the above-described other organic dyes or fluorescent dyes.

[0090] In addition to the above-described polarization dye, the above-described dyeing solution may further contain a dyeing assistant as necessary. Examples of the dyeing assistant include sodium carbonate, sodium hydrogen carbonate, sodium chloride, sodium sulfate (Glauber's salt), anhydrous sodium sulfate, and sodium tripolyphosphate, etc., and sodium sulfate is preferred. The content of the dyeing assistant can be arbitrarily adjusted depending on the immersion time and the temperature of the dyeing solution based on the dyeability of the polarization dye used, but it is preferably 0.1 to 10% by mass, and more preferably 0.1 to 2% by mass in the dyeing solution.

[0091] After the polarization pigment adsorption / impregnation step, an optional pre-washing step can be carried out to remove the staining solution adhering to the surface of the substrate in this step. By carrying out the pre-washing step, it is possible to suppress the transfer of the organic dye remaining on the surface of the substrate into the liquid to be processed next. In the pre-washing step, water is generally used as the cleaning liquid. As the cleaning method, it is preferable to immerse the substrate stained with the cleaning liquid. On the other hand, it can also be cleaned by applying the cleaning liquid to the substrate. The cleaning time is not particularly limited, but is preferably 1 to 300 seconds, more preferably 1 to 60 seconds. The temperature of the cleaning liquid in the pre-washing step needs to be a temperature at which the material constituting the substrate does not dissolve, and generally the cleaning treatment is carried out at 5 to 40°C. In addition, since the performance of the polarized light emitting film is not particularly greatly affected even without the pre-washing step, the pre-washing step can also be omitted.

[0092] (Crosslinking step) After the polarization dye adsorption / impregnation step or the preliminary washing step, the polarization dye in the substrate can be crosslinked. It is preferable to immerse the substrate in a treatment solution containing a crosslinking agent to crosslink the polarization dye in the substrate. On the other hand, the treatment solution may be applied or coated on the substrate. As the crosslinking agent in the treatment solution, it is preferable to use a solution containing boric acid. The solvent in the treatment solution is not particularly limited, but water is preferable. The concentration of boric acid in the treatment solution is preferably 0.1 to 15% by mass, and more preferably 0.1 to 10% by mass. The temperature of the treatment solution is preferably 30 to 80°C, and more preferably 40 to 75°C. Also, the treatment time of this crosslinking step is preferably 30 seconds to 10 minutes, and more preferably 1 to 6 minutes. In a preferred embodiment of the present invention, the method for producing a polarized light emitting film includes this crosslinking step, and the obtained polarized light emitting film emits polarized light with high brightness and high polarization degree. This is an excellent effect that cannot be expected at all from the function of boric acid that has been used for the purpose of improving water resistance or light transmittance in the prior art. Further, in the crosslinking step, if necessary, a fixing treatment may be further performed together with an aqueous solution containing a cationic polymer compound. The fixing treatment enables the immobilization of the polarization dye. At this time, as the cationic polymer compound, for example, cationic ions, dicyan-based such as dicyanamide and formalin polymerization condensate, polyamine-based such as dicyandiamide·diethylenetriamine polycondensate, polycationic-based such as epichlorohydrin·dimethylamine addition polymer, dimethyldiallylammonium chloride·dioxide ion copolymer, diallylamine salt polymer, dimethyldiallylammonium chloride polymer, allylamine salt polymer, dialkylaminoethyl acrylate quaternary salt polymer, etc. are used.

[0093] (Stretching step) After performing the crosslinking step, a stretching step is carried out. The stretching step is performed by uniaxially stretching the substrate in a certain direction. The stretching method may be either a wet stretching method or a dry stretching method. The stretching ratio is preferably 3 times or more and less than 10 times, and more preferably 5 to 9 times.

[0094] In the dry stretching method, when the stretching heating medium is an air medium, it is preferable to stretch the substrate at a temperature of the air medium from room temperature to 180°C. Also, the humidity is preferably in an atmosphere of 20 to 95% RH. Examples of the heating method of the substrate include, but are not limited to, the in-roll-zone stretching method, the roll heating stretching method, the hot pressing stretching method, the infrared heating stretching method, etc. The dry stretching process may be carried out by single-stage stretching or multi-stage stretching of two or more stages.

[0095] In the wet stretching method, it is preferable to stretch the substrate in water, a water-soluble organic solvent, or a mixed solution thereof. More preferably, the stretching treatment is carried out while immersing the substrate in a solution containing at least one cross-linking agent. As the cross-linking agent, for example, boric acid in the above cross-linking agent step can be used, and preferably, the stretching treatment can be carried out in the treatment solution used in the cross-linking step. The stretching temperature is preferably 40 to 70°C, more preferably 45 to 60°C. The stretching time is usually 30 seconds to 20 minutes, preferably 2 to 7 minutes. The wet stretching process may be carried out by single-stage stretching or multi-stage stretching of two or more stages. Incidentally, the stretching treatment may optionally be carried out before the polarizing dye adsorption / impregnation step, and in this case, the orientation of the dye can also be carried out together at the time of dyeing.

[0096] (Washing step) After the stretching process is carried out, since precipitation of the cross-linking agent or foreign matter may adhere to the surface of the substrate, a washing step of washing the surface of the substrate can be carried out. The washing time is preferably 1 second to 5 minutes. As the washing method, it is preferable to immerse the substrate in a washing liquid. On the other hand, the washing liquid can also be applied to the substrate or washed by coating. Water is preferable as the washing liquid. The washing treatment may be carried out in one stage or in a multi-stage treatment of two or more stages. The temperature of the washing solution in the washing step is not particularly limited, but is usually 5 to 50°C, preferably 10 to 40°C, and may be room temperature.

[0097] As solvents for the solutions or treatment liquids used in the above-described respective steps, in addition to the above water, for example, alcohols such as dimethyl sulfoxide, N-methylpyrrolidone, methanol, ethanol, propanol, isopropyl alcohol, glycerin, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol or trimethylolpropane, amines such as ethylenediamine and diethylenetriamine, etc. may be mentioned. The solvent of the said solution or treatment liquid is not limited to these, but most preferably is water. Further, these solvents of the solution or treatment liquid may be used alone or in a mixture of two or more.

[0098] (Drying step) After the washing step, a drying step of the substrate is performed. The drying treatment can be carried out by natural drying. Also, in order to enhance the drying efficiency further, it can be carried out by compression with a roll, or removal of surface moisture by an air knife or a water-absorbing roll, etc., and further, blow drying can also be carried out. The temperature of the drying treatment is preferably 20 to 100°C, more preferably 60 to 100°C. The drying time is preferably 30 seconds to 20 minutes, more preferably 5 to 10 minutes.

[0099] According to the method exemplified above, a polarized luminescent film can be produced. Further, the water-soluble chromenopyridin-7-one compounds represented by formulas (1) to (2) can be used to produce a polarized luminescent film having various colors, for example, neutral gray, by a method of mixing and aligning with a liquid crystal or a coating method of sharing and aligning.

[0100] [Polarized luminescent plate] The polarized luminescent plate containing the above polarized luminescent film is also included in the present invention. In a preferred embodiment of the present invention, the polarized light emitting plate includes a transparent protective layer together with the above-described polarized light emitting film, and typically has a transparent protective layer on at least one surface of the above-described polarized light emitting film. The transparent protective layer is used to improve the water resistance, handleability, etc. of the polarized light emitting film. Therefore, it is preferable that the transparent protective layer does not affect the polarized light emitting function exhibited by the polarized light emitting film at all.

[0101] The above transparent protective layer is preferably a transparent protective layer excellent in optical transparency and mechanical strength. Further, the transparent protective layer preferably has a layer shape capable of maintaining the shape of the polarized light emitting film. In addition to transparency and mechanical strength, the transparent protective layer is preferably excellent in thermal stability, moisture shielding property, etc. Examples of materials for forming such a transparent protective layer include cellulose acetate-based films, acrylic-based films, fluorine-based films such as ethylene tetrafluoride / hexafluoropropylene copolymers, polyester resins, polyolefin resins, or polyamide-based resins, etc. Triacetyl cellulose (TAC) films and cycloolefin-based films are preferably used. The thickness of the transparent protective layer is preferably in the range of 1 μm to 200 μm, more preferably in the range of 10 μm to 150 μm, and particularly preferably 40 μm to 100 μm. The polarized light emitting plate having a transparent protective layer is not particularly limited, but can be produced, for example, by laminating a transparent protective layer on the polarized light emitting film according to a known formulation.

[0102] The above polarized light emitting plate may further include an adhesive layer for bonding the transparent protective layer to the polarized light emitting film between the transparent protective layer and the polarized light emitting film. The adhesive for forming the adhesive layer is not particularly limited, and examples include polyvinyl alcohol-based adhesives, urethane emulsion-based adhesives, acrylic-based adhesives, polyester-isocyanate-based adhesives, etc. A polyvinyl alcohol-based adhesive is preferably used. After bonding the transparent protective layer and the polarized light emitting film with an adhesive, the polarized light emitting plate can be produced by drying or heat treatment at an appropriate temperature.

[0103] In addition, the above-mentioned polarized light emitting plate may appropriately include various known functional layers such as an antireflection layer, an antiglare layer, and a further transparent protective layer, etc. These layers are typically provided on the exposed surface of the transparent protective layer. When manufacturing such layers having various functions, it is preferable to apply a material having various functions, for example, on the exposed surface of the transparent protective layer. Further, it is also possible to bond a layer or film having such a function, via an adhesive or a pressure-sensitive adhesive, for example, on the exposed surface of the transparent protective layer.

[0104] Examples of the above-mentioned further transparent protective layer include a hard coat layer such as an acrylic-based, urethane-based, polysiloxane-based one, etc. In addition, in order to further improve the single transmittance, an antireflection layer can also be provided on the exposed surface of the transparent protective layer. The antireflection layer can be formed, for example, by vapor-depositing or sputtering a substance such as silicon dioxide or titanium oxide on the exposed surface of the transparent protective layer, or by thinly applying a fluorine-based substance on the exposed surface of the transparent protective layer.

[0105] The above-mentioned polarized light emitting plate can further include a support as needed. Such a support preferably has a flat surface for attaching the polarized light emitting plate. Also, from the perspective of optical applications, it is preferably transparent. Transparent supports can be classified into inorganic supports and organic supports. Examples of inorganic supports include supports made of inorganic materials such as soda glass, borosilicate glass, quartz, sapphire, and spinel. Examples of organic supports include supports made of organic materials such as acrylic, polycarbonate, polyethylene terephthalate, polyethylene naphthalate, and cycloolefin polymer. The thickness and size of the support are not particularly limited and can be determined as appropriate. Also, for a polarized light emitting plate having a support, in order to further improve the single transmittance, it is preferable to provide an antireflection layer on one or both of the support surface or the polarized light emitting plate surface. To adhere the polarized light emitting plate to the flat surface of the support, a transparent adhesive (adhesive) can be applied to the flat surface of the support, and then the polarized light emitting plate can be attached to this coated surface. The adhesive or adhesive to be used is not particularly limited, and commercially available ones can be used, and an acrylic ester-based adhesive or adhesive is preferable.

[0106] Also, the above-mentioned polarized light emitting plate can be made into a circularly polarized light emitting plate or an elliptically polarized light emitting plate by attaching a retardation plate. For example, when a support is further provided on the polarized light emitting plate, if the support is used as a retardation plate, these circular or elliptical polarized light emitting plates can be produced. Examples of retardation plates generally include those having a retardation value of 1 / 4λ or 1 / 2λ with respect to the light absorption wavelength or emission wavelength, but are not limited thereto. By having a retardation value of 1 / 4λ, it functions as a circular polarizing plate or a circularly polarized light emitting plate with respect to that wavelength, and by having a retardation value of 1 / 2λ, uses such as converting the polarization in a 90° direction become possible. Thus, various functional layers, supports, etc. can be further provided on the polarized light emitting plate, and such a polarized light emitting plate can be used in various products such as liquid crystal projectors, calculators, watches, notebook computers, word processors, liquid crystal TVs, car navigations, indoor and outdoor measuring instruments and displays, lenses, or glasses.

[0107] In a preferred embodiment of the present invention, the polarized light emitting film and the polarized light emitting plate exhibit a high polarized light emitting effect in the visible light region. Further, since the polarized light emitting film and the polarized light emitting plate exhibit excellent durability against heat, humidity, light, etc., it is possible to maintain their performance even under harsh environments, and they have higher durability than conventional iodine-based polarizing plates, for example. Therefore, the polarized light emitting film and the polarized light emitting plate according to the preferred embodiment of the present invention are applicable to various display devices such as liquid crystal displays that require high polarization degrees in the visible light region and high durability under harsh environments, for example, televisions, wearable terminals, tablet terminals, smartphones, in-vehicle monitors, digital signage used outdoors or indoors, smart windows, etc.

[0108] [Polarized light emission wavelength] In an embodiment of the present invention, the maximum polarized light emission wavelength of the water-soluble chromenopyridine-7-one compound or its salt contained in the polarized light emitting film and the polarized light emitting plate is preferably in the wavelength range of 550 to 780 nm, more preferably in the wavelength range of 550 to 700 nm. By having the maximum emission wavelength in the above wavelength range, red-orange polarized light emission can be obtained. Further, the wavelength range of polarized light emission may have a polarized light emission with an emission intensity of 0.5 or less, more preferably 0.3 or less, in the emission wavelength range of 400 to 550 nm when the emission intensity of the maximum polarized light emission wavelength in the wavelength range of 550 to 700 nm is normalized to 1. Among the preferable emission intensities in the wavelength range of 400 to 550 nm, when the emission intensity is strong, pink polarized light emission can also be obtained.

[0109] The degree of polarization based on light emission is evaluated by DOP. DOP is calculated using Equation (I) from the emission intensity ratio (Sr0) of each wavelength, with the emission intensity at the maximum emission wavelength of the polarized light emitting plate being set to 1, and the linear polarization degree (DOLP) of the emitted light obtained from the emission spectro-photometer.

[0110]

Equation

[0111] It is preferable that the DOP at the maximum emission wavelength in the emission wavelength range of 550 to 780 nm of the polarized light emitting plate is 0 to 1.0. More preferably, the DOP in the emission wavelength range of 550 to 700 nm is preferably 0.5 to 1.0. By obtaining the DOP in the emission wavelength range that satisfies the above, polarized light emission derived from red-orange can be obtained.

[0112] [Display device] A display device including the above-described polarized light emitting film or polarized light emitting plate is also included in the present invention. In an embodiment of the present invention, the display device exhibits a polarization emission effect by irradiating light in the ultraviolet to visible region, for example, light with a wavelength of 300 to 600 nm. By utilizing this effect, display becomes possible. The display device according to the embodiment of the present invention has a high degree of polarization in visible light emission itself. Therefore, there is no reduction in the transmittance in the visible light region like a conventional polarizing plate, or even if there is a reduction in transmittance, the reduction in transmittance is significantly smaller than that of a conventional polarizing plate. The transmittance corrected for visual sensitivity of a conventional polarizing plate, for example, an iodine-based polarizing plate or a dye-based polarizing plate containing other dye compounds is about 35 to 45%. The reason is that a conventional polarizing plate has both a vertical axis and a horizontal axis as the light absorption axes, but absorbs light incident on one of the vertical or horizontal axes. That is, polarization occurs by absorbing light on one axis and transmitting light on the other axis. In such a case, since the light on one axis is absorbed and not transmitted, the transmittance inevitably becomes 50% or less. On the other hand, the polarization emission film or polarization emission plate according to the embodiment of the present invention has an absorption band in the vicinity of 300 to 600 nm, particularly 350 to 500 nm. That is, there is a light absorption effect in the ultraviolet light region and the short-wavelength side of the visible light region, and it exhibits a polarization emission effect of emitting light polarized in the visible light region. Therefore, there is no light loss compared to using a conventional absorption-type polarizing plate, and the reduction in transmittance is very small like that of a conventional polarizing plate. From this, a display device using the polarization emission film or polarization emission plate according to the embodiment of the present invention, for example, a liquid crystal display, can obtain higher brightness than a display device such as a liquid crystal display using a conventional polarizing plate. In addition, since the display device using the polarization emission film or polarization emission plate according to the embodiment of the present invention has high transparency, for example, a substantially transparent display can be obtained while being a liquid crystal display. Also, since it can be designed so that polarization emission passes through during display of characters, images, etc., a display that can be displayed while being a transparent liquid crystal display can be obtained, that is, a display in which characters, etc. can be displayed on a transparent display can be obtained. Thus, according to the embodiment of the present invention, the display device can be a transparent liquid crystal display with no light loss, particularly a see-through display.

[0113] In addition, according to an embodiment of the present invention, since the display device can be polarized even with respect to ultraviolet light that is invisible to the human eye, it can be applied to a liquid crystal display that can be displayed by ultraviolet light. For example, by recognizing an image or the like displayed by light in the ultraviolet region with a computer or the like, a simple and highly secure liquid crystal display that can be visually recognized only when irradiated with ultraviolet light can be manufactured.

[0114] In addition, since the above display device exhibits a polarization emission effect by irradiating ultraviolet light and a liquid crystal display using the polarization emission can be manufactured, it is possible to realize a liquid crystal display using ultraviolet light instead of a normal liquid crystal display using visible light. That is, in a dark space without light, as long as it is a space where ultraviolet light can be irradiated, it is possible to manufacture a light-emitting liquid crystal display in which characters, images, etc. are displayed.

[0115] Furthermore, since the light absorption bands are different between the visible light region and the ultraviolet light region, it is also possible to manufacture a display in which a liquid crystal display portion that can be displayed by light in the visible light region and a liquid crystal display portion by light displayed by the polarization emission effect of ultraviolet light coexist. Although there have been displays that can perform two different displays, there is no display that can perform different displays by different light sources in the ultraviolet light region and the visible light region while being the same liquid crystal panel. Therefore, the display device according to the present invention can manufacture a novel display by having the above polarization emission film or polarization emission plate.

[0116] In the liquid crystal display according to the embodiment of the present invention, the liquid crystal cell is not limited to, for example, a TN liquid crystal cell, an STN liquid crystal cell, a VA liquid crystal cell, an IPS liquid crystal cell, etc., and the liquid crystal display can be used in any liquid crystal display mode. Since the polarization emission film or polarization emission plate containing the water-soluble chromenopyridine-7-one compound or a salt thereof has high durability, it can also be used for in-vehicle or outdoor display liquid crystal displays.

Example

[0117] Hereinafter, the present invention will be described in more detail with reference to Examples, but these are illustrative and do not limit the present invention in any way. Also, the “%” and “parts” described below are based on mass unless otherwise specified. Further, in each structural formula of the compounds used in each Example and Comparative Example, acidic functional groups such as sulfo groups are described in the form of free acids.

[0118] [Example 1] (Synthesis Example 1) A compound of the following formula (4) was synthesized by the synthesis method of Example 6 described in JP-A-49-077939.

[0119] [Chemical Formula] 50.0 parts of the obtained compound of formula (4) was added to 600 parts of 15% fuming sulfuric acid and reacted at 40 ° C. for 24 hours, then poured into 2000 parts of ice water and salted out with sodium chloride to obtain 10.0 parts of a water-soluble chromenopyridin-7-one compound according to the present invention represented by the following formula (5).

[0120] [Chemical Formula]

[0121] (Production of Polarization Emission Film and Polarization Emission Plate) A polyvinyl alcohol film with a thickness of 75 μm (VF-PS#7500 manufactured by Kuraray Co., Ltd.) was immersed in water at 40 °C for 3 minutes to swell the film. The swollen film was immersed in an aqueous solution at 45 °C containing 1.0 part of the water-soluble chromenopyridine-7-one compound of the above formula (5) obtained in Synthesis Example 1, 1.0 part of mirabilite, and 1000 parts of water for 3 minutes to impregnate the film with the water-soluble chromenopyridine-7-one compound of formula (5). The film containing the water-soluble chromenopyridine-7-one compound of formula (5) was immersed in a 3% boric acid aqueous solution at 50 °C for 5 minutes and stretched 5 times. The stretched film was washed with water at room temperature for 20 seconds while maintaining a tension state, and then dried to produce a polarized luminescent film. On both sides of the obtained polarized luminescent film, a triacetyl cellulose film (ZRD-60 manufactured by Fuji Film Co., Ltd.) (thickness: 60 μm) containing no ultraviolet absorber was laminated using a polyvinyl alcohol-based adhesive to produce a polarized luminescent plate. This polarized luminescent plate was used as the measurement sample in Example 1.

[0122] [Example 2] (Synthesis of water-soluble chromenopyridine-7-one compound: Synthesis Example 2) 10.0 parts of the compound of the above formula (5) was added to 60 parts of sulfuric acid and reacted at 70 °C for 16 hours. Then, it was poured into 200 parts of ice water and salted out using sodium chloride to synthesize 4.5 parts of the water-soluble chromenopyridine-7-one compound according to the present invention represented by the following formula (6).

[0123] [Chemical formula]

[0124] (Production of polarized luminescent film and polarized luminescent plate) Next, using the water-soluble chromenopyridine-7-one compound represented by the above formula (6), the same operations as in Example 1 were performed to produce a polarized luminescent plate. This polarized luminescent plate was used as the measurement sample in Example 2.

[0125] [Comparative Example 1] In Example 1 above, the same operations as in Example 1 were performed except that the compound described in Example 1 of JP-A-2021-189409 was used instead of the water-soluble chromenopyridin-7-one compound represented by the above formula (5), and a measurement sample was prepared.

[0126] [Evaluation] The evaluation of each measurement sample obtained in Examples 1 to 2 and Comparative Example 1 was carried out as follows.

[0127] (Observation of emission color) Under a dark room, each measurement sample prepared in Examples 1 to 2 and Comparative Example 1 was irradiated with UV light using a commercially available UV-LED black light having a peak wavelength of 375 nm, and the emission color of each measurement sample was observed.

[0128] (Measurement of polarized emission) The emission intensity and the degree of polarization of the emitted light of each measurement sample were measured by the generally known Stokes parameter method using an emission spectrophotometer (Spectro-Polarimeter Poxi-Spectra manufactured by Tokyo Instruments Co., Ltd.). The emission intensity (S0) obtained by irradiating the measurement sample with light of 375 nm was set such that the emission intensity at the maximum emission wavelength was 1, and the emission intensity ratio (Sr0) at each wavelength was calculated. From the calculated Sr0 and the linear degree of polarization (DOLP) of the emitted light obtained from the emission spectrophotometer, the degree of polarization (DOP) based on emission was calculated using Equation (I).

[0129] [Equation]

[0130] Each measurement sample of Examples 1 to 2 and Comparative Example 1 was placed on black paper, and a commercially available UV-LED black light with a peak wavelength of 375 nm was used to irradiate UV light in a dark room, and the emission color was observed visually. The hue results of the observed emission colors are shown in Table 1 below. A peach color was observed for the measurement sample of Example 1, and an orange color was observed for the measurement sample of Example 2. On the other hand, Comparative Example 1 emitted light in a yellow (yellowish green) with low brightness and strong greenish tint. That is, it was visually observed that the films prepared using the water-soluble chromenopyridine-7-one compounds as in Examples 1 and 2 emitted light in the red-orange to peach color range.

[0131]

Table 1

[0132] Figure 1 shows the spectra of the emission intensity ratio Sr0 of each measurement sample. Since the measurement samples of Examples 1 to 2 have a maximum emission wavelength near 580 nm, it can be seen that they emit light in the red-orange range. However, compared with Example 2, in Example 1, the Sr0 spectrum was clearly observed near 400 to 550 nm as shown in Figure 2. Thus, it is considered that the red-orange light near the maximum emission wavelength of 580 nm and the emission were mixed in a wide band near 400 to 550 nm, and it appeared as peach-colored emission visually as shown in Table 1. Comparative Example 1 had a maximum emission wavelength at 544 nm. Also, it had a strong peak at 544 nm and a weak peak at 580 nm. Since these peaks were close to each other and overlapped, it is considered that the strong yellowish green emission component derived from 544 nm and the weak red-orange emission component derived from 580 nm were mixed, showing yellowish green emission as a mixed color. Therefore, in Comparative Example 1, peach or red-orange emission could not be obtained.

[0133] Figure 3 shows the graph of DOP for each wavelength of the measurement samples obtained in Examples 1 to 2 and Comparative Example 1. In the measurement samples of each of the Examples and Comparative Example prepared this time, these measurement samples had emission performance, and the emitted light had polarization, and it was confirmed that each of the prepared films was an emission polarizing plate. Also, as shown in Fig. 3, the measurement samples of Examples 1 to 2 show high DOP values centered around 550 to 580 nm, have a polarization emission function in the visible light region near 550 to 580 nm, and function as a polarization emission plate in the same region. On the other hand, Comparative Example 1 had polarization emission at 544 nm, which is on the shorter wavelength side than Examples 1 and 2, and near 580 nm, which is the same band as Examples 1 and 2. Comparing the maximum emission wavelengths at 550 to 580 nm, it can be seen that the DOP at 580 nm in Comparative Example 1 is low, and the polarization emission function is inferior to that of Examples 1 to 2.

[0134] Table 2 shows the maximum emission wavelengths of the respective measurement samples obtained in Examples 1 to 2 and Comparative Example 1, the DOP at the maximum emission wavelengths, and the DOP at 580 nm due to red-orange emission. As confirmed in Fig. 1, it was found that the measurement samples of Examples 1 to 2 all had maximum emission wavelengths of 550 nm or more. Also, it was found that the DOPs at these maximum emission wavelengths all had high DOPs of 0.5 or more. On the other hand, in Comparative Example 1, although the DOP at the maximum emission wavelength was 0.510, since the maximum emission wavelength was 544 nm, which is on the shorter wavelength side than Examples 1 to 2, pink or red-orange emission could not be obtained. In addition, regarding the DOP related to the emission color of 580 nm that contributes to the red-orange system, the measurement samples of Examples 1 and 2 showed higher DOPs than Comparative Example 1. From these results, it was found that the measurement samples of Examples 1 to 2 prepared using the water-soluble chromenopyridin-7-one compound having the structure of the above formula (1) are useful as a polarization emission plate having a clear polarization emission function in the range of 550 to 580 nm.

[0135]

Table 2

[0136] (Durability Test) For each measurement sample of Examples 1 to 2, a durability test was carried out under the following two conditions. 1) 105 °C, 1000 hours 2) 60 °C, relative humidity 90%, 1000 hours

[0137] As a result of the durability test, no change in the DOP value was observed in each measurement sample of Examples 1 to 2. From this, it can be seen that the samples of Examples 1 to 2 have high durability even under harsh environments.

Industrial Applicability

[0138] The display device produced using the polarizing light emitting film or polarizing light emitting plate containing the water-soluble chromenopyridin-7-one compound of the present invention has a maximum polarized light emission wavelength particularly in the region of 550 to 780 nm and can display images by polarized light emission over a long period of time. Therefore, it can be applied to a wide range of uses such as televisions, personal computers, tablet terminals, and further, transparent displays (see-through displays). Furthermore, since the polarizing light emitting film produced using the above water-soluble chromenopyridin-7-one compound can emit light by UV light, it can also be applied to displays and media that require high security.

Claims

1. A polarized light emitting film containing a water-soluble chromenopyridin-7-one compound represented by the following formula (1) or a salt thereof. 【Chemical 1】 (In formula (1), Q represents an arbitrary substituent, and R １ and R ２ are each an optionally substituted C1-4 alkyl group, X is a cyano group or a carbamoyl group, and n represents an integer of 1 or 2.)

2. The polarized light emitting film according to Claim 1, wherein the water-soluble chromenopyridin-7-one compound or a salt thereof is represented by the following formula (2). [Chemical 2] (In formula (2), R １ and R ２ are each an optionally substituted C1-4 alkyl group, and X represents a cyano group or a carbamoyl group.)

3. The polarized light emitting film according to Claim 1 or 2, including a substrate.

4. The polarized light emitting film according to Claim 3, wherein the substrate is made of a polyvinyl alcohol resin or a derivative thereof.

5. The polarized light emitting film according to any one of Claims 1 to 4, containing one or more organic dyes or fluorescent dyes other than the water-soluble chromenopyridin-7-one compound or a salt thereof.

6. A polarized light emitting panel including the polarized light emitting film according to Claim 5 and a transparent protective layer provided on at least one surface thereof.

7. A display device including the polarized light emitting film according to Claim 5 or the polarized light emitting panel according to Claim 6.

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