JP2008088426A - New cyanine compound and use of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cyanine compound having a maximum absorption in a wavelength range of 400-1,100 nm, high in solubility in a solvent such as ketone etc., and excellent in workability, and to provide an optical filter for the use of near infrared absorption and image property improvement. <P>SOLUTION: The cyanine compound is represented by formula (1), wherein, Q<SB>1</SB>and Q<SB>2</SB>each forms a nitrogen-containing condensed heterocyclic ring that may each have independently a substitution group, R<SB>1</SB>and R<SB>2</SB>each represents an alkyl or alkenyl group that each may have independently a substitution group, D represents a connecting group for forming mono-, di-, or tri-carbocyanine, and X<SP>-</SP>represents tris(halogenoalkylsulfonyl)methide anion. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a novel cyanine compound, a light absorber using the compound, and an optical filter using the light absorber. Specifically, a novel cyanine compound having a high molecular extinction coefficient (mass extinction coefficient), a sharp absorption waveform, and excellent solvent solubility, a visible to near-infrared absorber using the same, and the light absorber are used. The present invention relates to an optical filter, particularly a near infrared absorption filter for plasma display panels and a filter for improving image characteristics.

Plasma display panels, which are attracting attention as large-sized thin TVs and displays, require electromagnetic shielding, near-infrared shielding, neon-cutting filters, neon-cutting filters, etc. to block electromagnetic waves, near-infrared rays, and neon light that are inevitably generated due to their mechanisms In this regard, for example, Patent Document 1 is known. In addition, for the purpose of blocking bright lines derived from neon and the like, and preventing reflection of fluorescent lamps and the like, dyes used for improving image characteristics of displays and resin compositions such as films and filters using the same are being studied. As a dye for improving image characteristics, a dye having sharp absorption at a specific wavelength for blocking generated electromagnetic waves, near infrared rays, neon light and the like is required.
Conventionally, cyanine compounds as absorbers of 400 nm to 1100 nm, that is, visible light to infrared ray, required for plasma display panels are described in Patent Document 2 and Patent Document 3. Among them, cyanine compounds whose counter ions are hexafluoroantimonate ions are mainly used because of their excellent heat resistance.

  However, none of these dyes are satisfactory in terms of processability (solubility in coating solvents), heat resistance, light resistance, absorption rate, transmittance, etc., and compounds containing antimony fall under deleterious substances, In recent years, compounds that do not contain heavy metals have been desired in the industrial field where the use of heavy metals and the like is regulated, particularly in the field of electrical materials. Patent Document 4 describes compounds that do not contain heavy metals, but these compounds have insufficient solubility in solvents such as methyl ethyl ketone used for coating and the like, and compounds with better workability have been demanded. Patent Document 5 describes a dye having a fluorinated alkylsulfonyl counter ion.

JP 2000-81511 A Japanese Patent Publication No. 5-37119 Japanese Patent No. 3045404 International Publication No. 2006/006573 Pamphlet JP-A-8-253705

  The present invention has been made in view of such circumstances, and an object of the present invention is a cyanine having maximum absorption in a wavelength range of 400 nm to 1100 nm, high solubility in solvents such as ketones, and excellent workability. An object is to provide a compound and an optical filter for improving near-infrared absorption and image characteristics using the compound.

As a result of diligent efforts to solve the above problems, the present inventors have completed the present invention. That is, the present invention relates to the following 1) to 12).
1)
Following formula (1)

[Wherein, Q ₁ and Q ₂ each independently form a nitrogen-containing condensed heterocyclic ring which may have a substituent, and R ₁ and R ₂ each independently have an alkyl which may have a substituent. An alkenyl group which may have a group or a substituent, D represents a linking group for forming a mono, di or tricarbocyanine, and X ⁻ represents a tris (halogenoalkylsulfonyl) methide anion]
A cyanine compound represented by:

2)
Wherein X ^- 1) above cyanine compound according tris (trifluoromethanesulfonyl) methide anion.
3)
The nitrogen-containing condensed heterocyclic ring formed by Q ₁ and Q ₂ is one selected from the following formulas (2) to (6): 1) or 2) The cyanine compound (nitrogen-containing formed by Q ₂ ) In the case of a fused heterocycle, the corresponding structural formula shall be read).

[Wherein R represents the same meaning as R ₁ and R ₂ , R ₃ represents a halogen atom, an alkyl group, an alkoxy group or a nitro group, and p represents an integer of 0 to 2]

4)
Cyanine compound as described in any one of said 1) -3) whose D is 1 type chosen from following formula (8)-formula (12).

[In the formula, Y represents a hydrogen atom, a halogen atom, a phenyl group, a diphenylamino group or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site.]

5)
R ₁ and R ₂ are each independently an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an alkoxyalkyl group having 3 to 20 carbon atoms, an alkoxyalkoxyalkyl group having 4 to 20 carbon atoms, a carbon number Cyanine compound as described in any one of said 1) -4) which is a 2-20 alkenyl group.
6)
The cyanine compound according to any one of 1) to 5) above, wherein R ₁ and R ₂ are each independently a methyl group, an n-butyl group, a methoxyethyl group, or an n-butoxyethyl group.
7)
Any of the nitrogen-containing condensed heterocyclic rings formed by Q ₁ and Q ₂ in formula (1) described in 1) above can be obtained from formula (2), formula (3), or formula (5) described in 3) above. One selected, R ₃ in the formula (2), formula (3) or formula (5) is a halogen atom, and p is an integer of 0 or 1;
R ₁ and R ₂ in formula (1) described in 1) above are each independently a methyl group, an n-butyl group, a methoxyethyl group, or an n-butoxyethyl group;
D is any one of the formula (8), the formula (9), the formula (11), or the formula (12) described in the above 4), and the formula (8), the formula (9), the formula (11), or the formula Y in (12) is a hydrogen atom or a chlorine atom;
X ⁻ is a tris (trifluoromethanesulfonyl) methide anion;
The cyanine compound according to 1) above,
However, the nitrogen-containing fused heterocyclic ring formed by Q ₂ is a replacement of the structural formula of the nitrogen-containing fused heterocyclic ring formed by Q ₁ with the structural formula corresponding to Q ₂ .
8)
The following formula (201)

[Wherein, the nitrogen-containing condensed heterocyclic ring formed by Q ₂ is one selected from the following formulas (202) to (204), and R ₄ and R ₅ are each independently a C1-C5 alkyl group or C1 represents -C5 alkoxy C1-C3 alkyl group, _{R 6} is a hydrogen atom, a C1-C5 alkyl group or a phenyl group, Y represents a halogen atom or a phenyl group, X ^- and tris (trifluoromethylsulfonyl) methide anion To express. ]

［式中、Ｒ_７は、水素原子、ハロゲン原子又はニトロ基を表す。］

[Wherein R ₇ represents a hydrogen atom, a halogen atom or a nitro group. ]

The cyanine compound as described in 1) above.
9)
The cyanine compound according to any one of 1) to 8) above, which has maximum absorption in a wavelength range of 400 nm to 1100 nm in methanol.
10)
The light absorber using the cyanine compound as described in any one of said 1) -9).
11)
The light absorber according to 10) above, which is for near infrared absorption and / or for improving image characteristics.
12)
An optical filter using the light absorbent as described in 10) or 11) above.
13)
A plasma display panel using the optical filter described in 12) above.

  The cyanine compound of the present invention does not contain heavy metals such as antimony and arsenic, does not correspond to a deleterious substance, has a high molar extinction coefficient of 400 nm to 1100 nm, is excellent in heat resistance and light resistance, and is particularly soluble in solvents such as methyl ethyl ketone. And high workability. The light absorber of the present invention and the optical filter using the same do not contain heavy metals such as antimony, are extremely excellent in heat resistance, and hardly undergo thermal decomposition reactions. The optical filter of the present invention having such characteristics is suitable for infrared cut such as a heat insulating film or sunglasses, and particularly suitable as a near infrared absorption filter for plasma display or a filter for improving image characteristics. It is.

Hereinafter, the present invention will be described in detail. The cyanine compound of the present invention is a salt of a tris (halogenoalkylsulfonyl) methide anion, and the above general formula (1) [wherein Q ₁ and Q ₂ are each independently a nitrogen-containing condensed complex which may have a substituent. A ring is formed, R ₁ and R ₂ each independently represents an optionally substituted alkyl group or an optionally substituted alkenyl group, and D represents mono-, di- or tricarbocyanine. Represents a linking group for forming, and X ⁻ represents a tris (halogenoalkylsulfonyl) methide anion].

  The halogenoalkyl group in the tris (halogenoalkylsulfonyl) methide anion may be the same or different and includes a linear, branched or cyclic halogenoalkyl group which may have a substituent, and preferably has a carbon number. 1 to 36, more preferably a linear halogenoalkyl group which may have a substituent and having 1 to 10 carbon atoms, most preferably an unsubstituted carbon atom having 1 to 4 carbon atoms. A straight-chain halogenoalkyl group. The halogen atom of the halogenoalkyl group may be the same or different, and the substitution position is not particularly limited, and examples thereof include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and a fluorine atom, a chlorine atom and a bromine atom are preferable. Further, a fluorine atom is more preferable. Examples of halogenoalkyl groups include trifluoromethyl, difluoromethyl, monofluoromethyl, dichloromethyl, monochloromethyl, dibromomethyl, difluorochloromethyl, pentafluoroethyl, tetrafluoroethyl, Fluoroethyl group, trifluorochloroethyl group, difluoroethyl group, monofluoroethyl group, trifluoroiodoethyl group, heptafluoropropyl group, hexafluoropropyl group, pentafluoropropyl group, tetrafluoropropyl group, trifluoropropyl group, Difluoropropyl group, monofluoropropyl group, perfluorobutyl group, perfluorohexyl group, perfluorooctyl group, perfluorooctylethyl group, pentafluoroisopropyl group, heptafluor Isopropyl, perfluoro-3-methylbutyl group, a perfluoro-3-methylhexyl group and the like, a trifluoromethyl group is preferable. The tris (halogenoalkylsulfonyl) methide anion is preferably a tris (trifluoromethylsulfonyl) methide anion.

Although it does not specifically limit as a nitrogen-containing condensed heterocyclic ring which Q < ₁ >, Q < ₂ > in said Formula (1) forms, For example, a benzothiazole ring compound, a benzoxazole ring compound, or said Formula (2)-Formula (6) [ In the formula, R represents the same meaning as R ₁ and R ₂ , R ₃ represents a halogen atom, an alkyl group, an alkoxy group or a nitro group, and p represents an integer of 0 to 2]. A ring compound is mentioned.
For nitrogen-containing condensed heterocyclic ring Q ₂ forms to be replaced by a structural formula corresponding thereto.

Examples of the alkyl group in the alkyl group which may have a substituent of R, R ₁ and R ₂ include an alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 5 carbon atoms. For example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-amyl group, i-amyl group, t-amyl group, etc. Can be mentioned. Examples of the substituent include a 3- to 6-membered saturated heterocyclic group (for example, a tetrahydrofuryl group), a phenyl group optionally having an alkoxy group, a carbamoyl group, an alkoxy group (for example, a methoxy group, an ethoxy group, n-butoxy group, etc.), alkoxyalkoxy groups (for example, ethoxyethoxy group, methoxyethoxy group, methoxymethoxy group, etc.) and the like.
As R, R ₁ and R ₂ , an alkyl group having 1 to 20 carbon atoms which may have a substituent, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, and 3 to 20 carbon atoms And an alkoxyalkoxyalkyl group having 4 to 20 carbon atoms, such as a methyl group, an n-butyl group, a methoxyethyl group, an n-butoxyethyl group, a carbamoyl group, a phenethyl group or p- (isopropoxy) phenethyl. Groups etc. are preferred.

Examples of the alkenyl group which may have a substituent of R, R ₁ and R ₂ include an alkenyl group having 2 to 20 carbon atoms, preferably an unsubstituted alkenyl group having 2 to 5 carbon atoms, For example, an allyl group is mentioned.

As a halogen atom in R < ₃ > of Formula (2)-Formula (6), a fluorine atom, a chlorine atom, a bromine atom, etc. are mentioned, Preferably it is a chlorine atom.
Examples of the alkyl group in R ₃ of the formulas (2) to (6) include the same groups as the alkyl groups in the alkyl group which may have a substituent of R, R ₁ , or R ₂ .
As an alkoxy group in R < ₃ > of Formula (2)-Formula (6), the group which the alkyl group in the alkyl group which may have a substituent of said R, R < ₁ >, R < ₂ > couple | bonded with the oxygen atom is mentioned. Can be mentioned.
In Formula (2) to Formula (6), the substitution number P of R ₃ is 0 to 2, and when the substituent R ₃ is present, the substitution position is not particularly limited.

  The linking group for forming mono, di or tricarbocyanine as D in the formula (1) is the above formula (8) to the formula (12) [wherein Y is a hydrogen atom, a halogen atom, a phenyl group. And a diphenylamino group or an alkyl group having 1 to 4 carbon atoms, and * represents a binding site].

  Examples of the halogen atom in Y in the formulas (8) to (12) include a fluorine atom, a chlorine atom, and a bromine atom. The alkyl group having 1 to 4 carbon atoms includes a methyl group, an ethyl group, and an n-propyl group. , I-propyl group, n-butyl group, i-butyl group, t-butyl group and the like. Y is preferably a hydrogen atom, a chlorine atom or a phenyl group.

  As the cyanine compound of the present invention, a compound having a maximum absorption in a wavelength region of 400 nm to 1100 nm in methanol is preferable from the viewpoint of near-infrared absorption in a plasma display panel and the like and improvement of image characteristics.

The cyanine compound represented by the above formula (1) is produced by various methods. For example, it can be produced by the following method with reference to the method described in Patent Document 3.
Formula (13)

[Wherein Q has the same meaning as Q ₁ and Q _2, and R also has the same meaning as described above] 2 mol of the compound represented by formula (14) or formula (15)

[Wherein D represents the same meaning as described above]

[Wherein D represents the same meaning as described above]

1 mol of the compound represented by the above formula and 1 mol of tris (halogenoalkylsulfonyl) methide acid or a salt thereof such as sodium salt or potassium salt thereof, if necessary, in the presence of a base catalyst such as sodium acetate, potassium acetate, piperazine, piperidine or the like. In a dehydrating organic solvent such as acetic anhydride or a mixture of acetic anhydride and glacial acetic acid, for example, the mixture is heated and condensed at 50 to 140 ° C. for usually 10 minutes to 10 hours, preferably 30 minutes to 120 minutes. (A compound in which Q ₁ and R ₁ in Formula (1) are the same as Q ₂ and R ₂ , respectively) can be synthesized.

  An asymmetric cyanine compound can be synthesized in the same manner by using 1 mol of each compound of the formula (13) having different Q and R instead of 2 mol of the same compound of the formula (13).

  Alternatively, an aldehyde compound represented by formula (16) or formula (17)

[Wherein Q, R and Y have the same meaning as described above]
1 mol each of the same or different compound of formula (13) and 1 mol of tris (halogenoalkylsulfonyl) methide in the presence of a base catalyst such as sodium acetate, potassium acetate, piperazine, piperidine, etc., if necessary In a dehydrating organic solvent such as acetic anhydride or a mixture of acetic anhydride and glacial acetic acid, for example, the mixture is heated and condensed at 50 to 140 ° C. for usually 10 minutes to 12 hours, preferably 10 minutes to 60 minutes. Asymmetric cyanine compounds can also be synthesized.

  Moreover, as shown in the Example below, the monocarbocyanine compound can also be produced from the compound of the above formula (13), an ortho ester compound and tris (halogenoalkylsulfonyl) methide acid.

  The reaction product may be purified by recrystallization from methanol, ethanol or other organic solvent, if necessary.

  Next, the cyanine compound of this invention is illustrated below. However, the present invention is not limited to these.

Of the cyanine compounds of the present invention represented by the above formula (1), a compound represented by the above formula (201) is more preferable.
In the above formula (201), the nitrogen-containing fused heterocyclic ring formed by Q ₂ is one selected from the above formulas (202) to (204), and R ₄ and R ₅ are each independently C1-C5 alkyl. Group represents a C1-C5 alkoxy C1-C3 alkyl group, R ₆ represents a hydrogen atom, a C1-C5 alkyl group or a phenyl group, Y represents a halogen atom or a phenyl group, and X ⁻ represents tris (trifluoromethylsulfonyl). ) Represents the metide anion.

When R ₄ and R ₅ in the above formula (201) are a C1-C5 alkyl group, the alkyl group may be linear, branched or cyclic, but is preferably linear or branched alkyl. In the case of branched chain alkyl, a C3-C5 alkyl group is preferred, and one having a branched carbon atom other than the carbon atom substituted with a nitrogen atom is more preferred.
Specific examples of the straight chain C1-C5 alkyl group include methyl, ethyl, n-propyl, n-butyl and n-pentyl (amyl), and n-butyl is preferable.
Specific examples of the branched C3-C5 alkyl group include isopropyl, isobutyl, sec-butyl, t-butyl, 1-methylbutyl, 2-methylbutyl, isoamyl, t-amyl, 1,2-dimethylpropyl, 1,1- Examples thereof include dimethylpropyl, and isobutyl, 2-methylbutyl, and isoamyl are preferable.
As the cyclic alkyl, a C3-C5 cyclic alkyl group is preferable, and specific examples thereof include cyclopropyl, cyclobutyl and cyclopentyl.
When R ₄ and R ₅ are C3-C5 alkoxy C1-C3 alkyl groups, both the alkoxy moiety and the alkyl moiety may have any structure of straight chain, branched chain and cyclic, but both are straight Those that are chains are preferred. Preferable specific examples include propoxymethyl, butoxymethyl, pentoxymethyl, propoxyethyl, butoxyethyl, pentoxyethyl, propoxypropyl, butoxypropyl, pentoxypropyl, more preferably propoxyethyl, butoxyethyl, pentoxy. Ethyl, more preferably butoxyethyl.

In the above formula (201), R ₆ represents a hydrogen atom, a C1-C5 alkyl group or a phenyl group. These are all preferable, but a hydrogen atom, a C1-C4 alkyl group or a phenyl group is more preferable.
When R ₆ is a C1-C5 alkyl group, the alkyl group may be linear, branched or cyclic, but is preferably linear or branched alkyl. These specific examples and preferred ones may be the same as those described for R ₄ and R ₅ above. However, when R ₆ is a branched alkyl, among the above descriptions, the C3-C4 alkyl group is More preferred.

  In said formula (201), Y represents a halogen atom or a phenyl group. These are all preferable, but a halogen atom is more preferable. Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. A fluorine atom, a chlorine atom and a bromine atom are preferable, and a chlorine atom is more preferable.

In the above formula (201), the nitrogen-containing fused heterocycle formed by Q ₂ is one selected from the above formulas (202) to (204). All of these are preferred, but more preferably, Q ₂ forms a nitrogen-containing fused heterocycle of formula (202) or (203), and the nitrogen-containing fused heterocycles at both ends forming carbocyanine are different from each other. Those having a structural formula are preferred. By setting it as such a structure, the solubility to an organic solvent can be improved more.
In the formula (201), the nitrogen atom to which carbon atoms "C" and R ₅ described bonded to the terminal double bond, has the formula (202) to (204) carbon atom "C" and R ₅ as described in Each corresponds to a bonded nitrogen atom.
Therefore, in the formulas (202) to (204), R ₅ has the same meaning as that of the formula (201) and preferred ones.

In the above formula (203), R ₇ represents a hydrogen atom, a halogen atom or a nitro group. These are all preferred, but more preferably a hydrogen atom or a halogen atom.
Specific examples of the halogen atom, including preferred ones, may be the same as those in the case where Y in the above formula (201) is a halogen atom.

As is clear from the comparison between the above formula (201) and the formula (1), in the above formula (201), the linking group represented by D in the formula (1) corresponds to 7 carbon atoms, Carbocyanine is formed. This is illustrated in the following formula (207). In the formula (207), the numbers 1 to 7 were respectively assigned to 7 carbon atoms forming tricarbocyanine.

The number of carbons of the linking group represented by D in the above formula (1) is the number corresponding to tricarbocyanine, that is, 7 is the maximum. By adopting this configuration, the wavelength range of 400 nm to 1100 nm in methanol. Thus, the cyanine compound of the present invention having maximum absorption is obtained. If a structure such as tetracarbocyanine having 9 or more carbon atoms, for example, 9 carbon atoms is used, maximum absorption cannot be obtained in the above-mentioned wavelength range, and therefore it is not included in the present invention.

  Hereinafter, compounds 49 to 57 are exemplified as specific examples of the compound represented by the formula (201). However, the present invention is not limited to these.

  The cyanine compound of the present invention is a light absorber, particularly a near infrared absorbing dye for filters, an image characteristic improving dye that absorbs unnecessary light emission and improves color purity, as shown in the examples below. It can be used as an absorber, and the light absorber is also included in the present invention. It can also be used for an optical information recording medium.

  An optical filter using a light absorber using the cyanine compound of the present invention is also included in the present invention. The optical filter may be one in which a resin layer containing the cyanine compound of the present invention is provided on a substrate, or the substrate itself is made of a resin composition (or a cured product thereof) containing the cyanine compound of the present invention. It may be a layer. The substrate is not particularly limited as long as it can be generally used for an optical filter, but a resin material is usually used. The thickness of the layer is usually about 0.1 μm to 10 mm, but can be appropriately determined according to the purpose such as the near infrared cut rate.

In addition, the content of the cyanine compound to be used can be appropriately determined according to the target near-infrared cut rate.
Examples of the resin material that can be used include polyethylene compounds such as polyethylene, polystyrene, polyacrylic acid, polyacrylate esters, polyvinyl acetate, polyacrylonitrile, polyvinyl chloride, and polyvinyl fluoride, and those vinyl compounds. Addition polymer, polymethacrylic acid, polymethacrylic ester, polyvinylidene chloride, polyvinylidene fluoride, poly (vinylidene fluoride), vinylidene fluoride / trifluoroethylene copolymer, vinylidene fluoride / tetrafluoroethylene copolymer, vinylidene cyanide / Vinyl compounds such as vinyl acetate copolymers or copolymers of fluorine compounds, fluorine-containing resins such as polytrifluoroethylene, polytetrafluoroethylene, polyhexafluoropropylene, polyamides such as nylon 6 and nylon 66 Polyimides, polyurethanes, polypeptides, polyesters such as polyethylene terephthalate, polycarbonate, polyether polyoxymethylene or the like, epoxy resins, polyvinyl alcohol, polyvinyl butyral, and the like.

The method for producing the optical filter of the present invention is not particularly limited. For example, the following methods known per se can be used.
(1) A method of preparing a resin plate or film by kneading the cyanine compound of the present invention into a resin and thermoforming it,
(2) A method for producing a resin plate or film by cast polymerization of the cyanine compound of the present invention and a resin monomer or a prepolymer of a resin monomer in the presence of a polymerization catalyst,
(3) A method of preparing a coating material containing the cyanine compound of the present invention and coating the transparent resin plate, transparent film, or transparent glass plate,
(4) A method for producing a laminated resin plate, a laminated resin film, or a laminated glass plate using a composition containing the cyanine compound of the present invention and a resin (adhesive),
Etc.

  As the production method of (1), the processing temperature, filming (resin plate) conditions, etc. are slightly different depending on the resin to be used. Usually, the cyanine compound of the present invention is added to the base resin powder or pellet, and 150 Examples thereof include a method of heating and dissolving at ˜350 ° C. and then molding to prepare a resin plate, or a method of forming a film (resin plate) with an extruder. The amount of the cyanine compound added varies depending on the thickness, absorption strength, visible light transmittance, etc. of the resin plate or film to be produced, but is usually about 0.01 to 30% by mass, preferably 0, based on the mass of the base resin. About 0.03 to 15% by mass is used.

In the method (2), the cyanine compound of the present invention and a resin monomer or a prepolymer of a resin monomer are injected into a mold in the presence of a polymerization catalyst and allowed to react and harden or poured into a mold. Solidify and mold until hard product in mold. Many resins can be molded by this method, and examples of such resins include (meth) acrylic resin, diethylene glycol bis (allyl carbonate) resin, epoxy resin, phenol-formaldehyde resin, polystyrene resin, and silicon resin. . Among them, the casting method by bulk polymerization of methyl methacrylate, which can obtain an acrylic sheet excellent in hardness, heat resistance, and chemical resistance, is preferable.
As the polymerization catalyst, known radical thermal polymerization initiators can be used, for example, peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide, diisopropyl peroxycarbonate, and azo compounds such as azobisisobutyronitrile. It is done. The amount used is generally 0.01 to 5% by mass relative to the total amount of the mixture. The heating temperature in the thermal polymerization is usually 40 to 200 ° C., and the polymerization time is usually about 30 minutes to 8 hours. In addition to thermal polymerization, a method of photopolymerization by adding a photopolymerization initiator or a sensitizer can also be employed.

  The method (3) includes a method in which the cyanine compound of the present invention is dissolved in a binder resin and a solvent to form a paint, and a method in which the cyanine compound is finely dispersed in the presence of the resin to form a water-based paint. In the former method, for example, aliphatic ester resin, acrylic resin, melamine resin, urethane resin, aromatic ester resin, polycarbonate resin, polyvinyl resin, aliphatic polyolefin resin, aromatic polyolefin resin, polyvinyl alcohol resin, polyvinyl modification Resins or the like or copolymer resins thereof can be used.

As the solvent, a halogen-based, alcohol-based, ketone-based, ester-based, aliphatic hydrocarbon-based, aromatic hydrocarbon-based, ether-based solvent, or a mixed solvent thereof can be used. The concentration of the cyanine compound varies depending on the thickness of the coating to be produced, the absorption strength, and the visible light transmittance, but is generally about 0.1 to 30% by mass with respect to the binder resin.
The paint thus obtained can be coated on a transparent resin film, transparent resin plate, transparent glass or the like with a spin coater, bar coater, roll coater, spray or the like to obtain a near infrared absorption filter.

The method (4) can be applied to known transparent adhesives for laminated glass such as silicon-based, urethane-based, acrylic-based resins, polyvinyl butyral adhesives, ethylene-vinyl acetate adhesives, etc. Optical resin by adhering transparent resin plates, resin plates and resin film, resin plates and glass, resin films, resin films and glass, and glass. Is made.
In addition, when kneading and mixing by each method, usual additives used for resin molding such as an ultraviolet absorber and a plasticizer may be added.

The optical filter of the present invention, particularly the near-infrared absorbing filter, may use only one or two or more of the cyanine compounds of the present invention as a near-infrared absorbing compound. Near infrared absorbing compounds other than these compounds may be used in combination. Examples of other near-infrared absorbing compounds that can be used in combination include metal complex compounds such as diimonium compounds, phthalocyanine compounds, and nickel dithiol complexes. When these other near infrared ray absorbing compounds that can be used in combination are cationic, the counter anion may be the same tris (halogenoalkylsulfonyl) methide anion as the cyanine compound of the present invention.
As the other near-infrared absorbing compound, a diimonium compound is particularly preferable, and a counter anion of the diimonium compound is preferably a tris (halogenoalkylsulfonyl) methide anion.

  Examples of the inorganic infrared near-absorbing compound that can be used in combination include copper, copper sulfide, copper compounds such as copper oxide, a mixture containing zinc oxide as a main component, a tungsten compound, and a mixture containing titanium oxide as a main component. Etc.

  In order to change the color tone of the optical filter, a dye having absorption in the visible region other than the cyanine compound of the present invention may be added. Alternatively, a filter containing only a dye for improving image characteristics can be prepared and later bonded to the near infrared absorption filter of the present invention to obtain a single image characteristic improvement and near infrared absorption filter.

When the near-infrared absorbing optical filter of the present invention is used for the front plate of a plasma display, the visible light transmittance is preferably as high as possible, and at least 40% or more, preferably 50% or more is required. The near infrared cut region is preferably 750 to 1100 nm, more preferably 800 to 1000 nm, and the average near infrared transmittance of the region is 50% or less, more preferably 30% or less, still more preferably 20% or less, particularly Preferably it is 10% or less.
In order to improve the image characteristics, it is preferable to use a compound having sharp absorption in the vicinity of a wavelength of 580 to 620 nm in order to absorb unnecessary neon light different from the ideal three primary colors. Furthermore, optical filters for improving image characteristics can be obtained by using a compound having sharp absorption at 490 to 550 nm as a countermeasure against reflection of fluorescent light, etc., and 560 to 580 nm for absorbing xenon emission. It is done.

  The optical filter of the present invention for absorbing near infrared rays is not limited to the front plate of a display, but can also be used for filter films that need to cut near infrared rays, such as heat insulating films, optical products, and sunglasses.

  The optical filter of the present invention does not contain antimony or arsenic, and is environmentally friendly. Compared to conventional near-infrared absorbing filters containing perchlorate ions, hexafluorophosphate ions or tetrafluoroborate ions, As shown, it has excellent heat and moisture heat stability. Furthermore, the solubility in a solvent is sufficient and the processability is also excellent. In particular, the optical filter of the present invention is very excellent in heat resistance, moisture heat resistance, and light resistance, and hardly undergoes a decomposition reaction due to heat, so that the visible portion is hardly colored. From such characteristics, it is suitable as a near-infrared absorption filter for plasma display, and a plasma display panel using the optical filter of the present invention is also included in the present invention.

  Hereinafter, the present invention will be described more specifically with reference to examples. In Examples, “part” means “part by mass” unless otherwise specified, and “%” means “% by mass”.

Example 1
10.6 parts of 1,3,3-trimethyl-2-methyleneindoline, 14.8 parts of triethyl orthoformate, and 10.3 parts of tris (trifluoromethanesulfonyl) methido acid (manufactured by 3M) in 75 parts of acetic anhydride The mixture was heated to reflux for 1 hour under reflux and then cooled to room temperature, and then the reaction solution was filtered with suction to remove insoluble impurities. 100 parts of water was added dropwise to the reaction solution, the precipitated crystals were suction filtered, the obtained crystals were recrystallized with 40 parts of methanol, the crystals were washed with 5 parts of methanol, washed with water and dried, then the compound 1 Of 8.2 parts. The spectral characteristics, decomposition temperature, and solubility of Compound 1 obtained here were as follows. In addition, as a decomposition temperature, the value of the weight loss start temperature by thermogravimetric-differential thermal analysis (TG-DTA) was shown.
Maximum absorption wavelength 544nm (in methanol)
Molar extinction coefficient 140,000 (in methanol)
Decomposition temperature about 278 ° C (TG-DTA)
Moreover, the solubility at room temperature in various solvents was as follows.
Methanol 1.3%
Methyl ethyl ketone (MEK) 12.2%
Cyclopentanone 6.1%

Example 2
15.7 parts of 5-chloro-1- (2-methoxyethyl) -3,3-dimethyl-2-methyleneindoline and 10.6 parts of 1,3,3-trimethyl-2-formylmethyleneindoline, tris (trifluoromethane (Sulfonyl) methidic acid (11.4 parts) was charged into a mixed solvent of 50 parts of acetic anhydride and 25 parts of acetic acid, heated under reflux for 2 hours under reflux and cooling, then cooled to room temperature, and then 25 parts of water was added to precipitate crystals. The crystals obtained by suction filtration were recrystallized from 40 parts of methanol, and the crystals were washed with 5 parts of methanol, washed with water and dried to obtain 18.3 parts of Compound 9. The spectral characteristics and decomposition temperature of the compound 9 obtained here were as follows.
Maximum absorption wavelength 550nm (in methanol)
Molar extinction coefficient 137,000 (in methanol)
Decomposition temperature about 276 ° C (TG-DTA)
Moreover, the solubility at room temperature in various solvents was as follows.
Methanol 2.2%
Methyl ethyl ketone (MEK) 6.3%
Cyclopentanone 3.3%

Example 3
1,4.9 parts of 4,5-benzo-1- (2-methoxyethyl) -3,3-dimethyl-2-methyleneindoline, 6.5 parts of malonaldehyde dianyl hydrochloride, 4.1 parts of sodium acetate and 50 parts of acetic acid Then, the mixture was heated to 60 ° C., 5.1 parts of acetic anhydride was added dropwise at 50 ° C. to 60 ° C. over 1 hour, and further stirred at 50 ° C. to 60 ° C. for 2 hours to complete the condensation reaction. Subsequently, after cooling to room temperature, the reaction solution was suction filtered to remove insoluble impurities. To this reaction solution, 11.4 parts of tris (trifluoromethanesulfonyl) methido acid was added dropwise, the precipitated crystals were suction filtered, the obtained crystals were recrystallized with 40 parts of methanol, and the crystals were washed with 5 parts of methanol. It was washed with water and dried to obtain 16.9 parts of the compound 17. The spectral characteristics and decomposition temperature of the compound 17 obtained here were as follows.
Maximum absorption wavelength 680nm (in methanol)
Molar extinction coefficient 220,000 (in methanol)
Decomposition temperature about 272 ° C (TG-DTA)
Moreover, the solubility at room temperature in various solvents was as follows.
Methanol 0.2%
Methyl ethyl ketone (MEK) 6.4%
Cyclopentanone 2.4%

Example 4
1,4.9 parts of 4,5-benzo-1- (2-methoxyethyl) -3,3-dimethyl-2-methyleneindoline and 4.5 parts of 2-chloro-1-formyl-3-hydroxymethylenecyclohexene were mixed with 25 parts of acetic acid. Then, the mixture was heated to 60 ° C., 5.1 parts of acetic anhydride was added dropwise at 50 ° C. to 60 ° C. over 1 hour, and further stirred at 50 ° C. to 60 ° C. for 2 hours to complete the condensation reaction. Subsequently, after cooling to room temperature, the reaction solution was suction filtered to remove insoluble impurities. To this reaction solution, 11.4 parts of tris (trifluoromethanesulfonyl) methydic acid was added dropwise, the precipitated crystals were suction filtered, the obtained crystals were recrystallized with 70 parts of N, N-dimethylformamide, and the crystals were dissolved in methanol 5 After washing with water, washing with water and drying, 19.1 parts of Compound 31 were obtained. The spectral characteristics and decomposition temperature of the compound 31 obtained here were as follows.
Maximum absorption wavelength 820nm (in methanol)
Molar extinction coefficient 270,000 (in methanol)
Decomposition temperature about 234 ° C (TG-DTA)
Moreover, the solubility at room temperature in various solvents was as follows.
Methanol 0.2%
Methyl ethyl ketone (MEK) 13.6%
Cyclopentanone 5.5%
Cyclohexanone 7.1%

Example 5
As in Example 4, substituting 3.9 parts of 2-chloro-1-formyl-3-hydroxymethylenecyclopentene for 4.5 parts of 2-chloro-1-formyl-3-hydroxymethylenecyclohexene in Example 4. Thus, 10.2 parts of the compound 34 was obtained. The spectral characteristics and decomposition temperature of the compound 34 obtained here were as follows.
Maximum absorption wavelength 845nm (in methanol)
Molar extinction coefficient 285,000 (in methanol)
Decomposition temperature about 217 ° C (TG-DTA)
Moreover, the solubility at room temperature in various solvents was as follows.
Methanol 0.1%
Methyl ethyl ketone (MEK) 1.1%
Cyclopentanone 2.6%

Example 6
Instead of 14.9 parts of 4,5-benzo-1- (2-methoxyethyl) -3,3-dimethyl-2-methyleneindoline in Example 4, 1- (n-butyl) benzo [c, d]- 9.2 parts of the compound 38 was obtained in the same manner as in Example 4 using 12.1 parts of 2-methyleneindoline. The spectral characteristics of Compound 38 obtained here were as follows.
Maximum absorption wavelength 1015nm (in methanol)
Molar extinction coefficient 180,000 (in methanol)

Example 7
Instead of 14.9 parts of 4,5-benzo-1- (2-methoxyethyl) -3,3-dimethyl-2-methyleneindoline in Example 4, 1- (n-butyl) benzo [c, d]- Using 12.1 parts of 2-methyleneindoline and using 5.1 parts of 1-formyl-3-hydroxymethylene-2-phenylcyclopentene instead of 4.5 parts of 2-chloro-1-formyl-3-hydroxymethylenecyclohexene In the same manner as in Example 4, 8.2 parts of the compound 40 was obtained. The spectral characteristics of the compound 40 obtained here were as follows.
Maximum absorption wavelength 1026nm (in methanol)
Molar extinction coefficient 230,000 (in methanol)

Comparative Example 1
A compound described as Compound Example 31 in Patent Document 4 was synthesized in the same manner as in Example 4 except that bis (trifluoromethanesulfonyl) imidic acid was used instead of tris (trifluoromethanesulfonyl) methido acid in Example 4. Spectral characteristics and decomposition temperature were as follows.
Maximum absorption wavelength 820nm (in methanol)
Molar extinction coefficient 270,000 (in methanol)
Decomposition temperature about 240 ° C (TG-DTA)

Comparative Example 2
The compound disclosed in Patent Document 3 was synthesized in the same manner as in Example 4 using potassium hexafluoroantimonate instead of tris (trifluoromethanesulfonyl) methide acid in Example 4. Spectral characteristics and decomposition temperature were as follows.
Maximum absorption wavelength 820nm (in methanol)
Molar extinction coefficient 270,000 (in methanol)
Decomposition temperature about 240 ° C (TG-DTA)

Solubility The solubility of the compound of Example 4 (Compound 31) and Comparative Example 1 and Comparative Example 2 is shown in Table 1.
[Table 1]
Sample Methanol MEK DMF Cyclohexanone Example 4 0.2% 13.6% 10.6% 7.1%
Comparative Example 1 0.1% or less 2.9% 10.7% 5.5%
Comparative Example 2 0.1% or less 0.4% 1.3% 1.8%

  From Table 1, it can be seen that the compound of the present invention is very excellent in solvent solubility, including methyl ethyl ketone, compared to the compound of the comparative example having the same cation skeleton and different anions, and therefore, it is a compound excellent in processability. Indicated.

Example 8
0.5 part of the compound 31 obtained in Example 4 was dissolved in 4.5 parts of tetrafluoropropanol. This solution was spin-coated on a 1.5 mm thick, 10 cm square polycarbonate plate at 2000 rpm × 10 seconds to form a dye film, and an infrared absorption filter was prepared.
Comparative Example 3
Compound of Comparative Example 1 which is a compound described in Patent Document 4 (Compound disclosed in Patent Document 4 having higher heat resistance and heat and moisture resistance stability than the hexafluoroantimonate disclosed in Patent Document 3) ) To prepare an infrared filter in the same manner as in Example 8.

Heat Stability Stability and Wet Heat Stability Test The filter of Example 8 or Comparative Example 3 was left in an oven at 80 ° C. for 7 days to conduct a heat stability test. Moreover, it was left to stand at 80 degreeC and 85RH (relative humidity%) for 7 days in a constant temperature and humidity chamber, and the moisture-and-heat-resistant stability test was implemented. Absorbance of the filter before and after the test was measured with a spectrophotometer (UV-3150, manufactured by Shimadzu Corporation), and the residual ratio of the dye was determined from the change in absorbance (OD value) at the maximum absorption wavelength using the following formula. The results of the obtained heat stability test and moisture heat stability test are shown in Tables 2-1 and 2-2.
Residual rate = (absorbance after test / absorbance before test) × 100

[Table 2-1] (Heat resistance stability test)
sample
Absorbance (OD value) Initial 7 days later Dye remaining rate Example 8 0.562 0.015 2.7%
Comparative Example 3 0.608 0.000 0.0%

[Table 2-2] (Moisture and heat stability test)
Compound No.
Absorbance (OD value) Initial 7 days later Dye remaining rate Example 8 0.562 0.458 81.5%
Comparative Example 3 0.608 0.386 63.5%

  From Tables 2-1 and 2-2, the filter prepared using the compound of the present invention is a pigment compared to the filter prepared using a compound of a comparative example having the same cation skeleton and different anions described in Patent Document 4. Since the residual ratio was high, it was shown that the stability under high temperature conditions and the stability under high temperature and high humidity conditions were excellent.

Examples 9-16
The compounds 39, 47, 49, 51, 52, 54, 55 and 56 represented by the above formula (201) were obtained by synthesis according to the methods of Examples 1 to 7, respectively. These are referred to as Examples 9 to 16, respectively. The physical properties of each compound obtained are shown in Table 3 below. The maximum absorption wavelength and molar extinction coefficient are values in a methanol solution, and the decomposition temperature is a weight loss starting temperature obtained from TG-DTA.

Comparative Example 4
A comparative compound represented by the following formula (206) according to the method of Examples 1 to 7 except that the tris (trifluoromethylsulfonyl) methide anion in the compound 49 is replaced with an anion of iodine atom. Got. This is referred to as Comparative Example 4. The physical properties of the obtained compound are shown in Table 3 below.

As is apparent from Table 3, among the compounds of the present invention of Examples 9 to 16 having excellent solvent solubility represented by the above formula (201), those having maximum absorption at a wavelength of 900 nm or longer form Q _2. In the nitrogen-containing condensed heterocyclic ring, the compounds 39, 49 and 56 represented by the above formula (204) have a solvent solubility in MEK of 0.3 to 0.6%. On the other hand, the solvent solubility of the compounds 47 and 51 to 56 in which the nitrogen-containing condensed heterocyclic ring formed by Q ₂ is the above formula (202) or (203) is 1.0 to 1.7% similarly. The solvent solubility of the compound containing the nitrogen-containing fused heterocycle represented by the above formula (204) is at least about 1.7 times as large as the maximum and 5.7 times as large as the maximum. It can be said that it is a preferred compound.

Claims (13)

Following formula (1)

[Wherein, Q ₁ and Q ₂ each independently form a nitrogen-containing condensed heterocyclic ring which may have a substituent, and R ₁ and R ₂ each independently have an alkyl which may have a substituent. An alkenyl group which may have a group or a substituent, D represents a linking group for forming a mono, di or tricarbocyanine, and X ⁻ represents a tris (halogenoalkylsulfonyl) methide anion]
A cyanine compound represented by: Wherein X ^- tris (trifluoromethane sulfonyl) cyanine compound of claim 1 wherein the methide anion. The nitrogen-containing condensed heterocyclic ring formed by Q ₁ and Q ₂ is one selected from the following formulas (2) to (6): Cyanine compound according to claim 1 or 2 (nitrogen-containing condensed formed by Q ₂ In the case of a heterocyclic ring, it shall be read as the corresponding structural formula).

[Wherein R represents the same meaning as R ₁ and R ₂ , R ₃ represents a halogen atom, an alkyl group, an alkoxy group or a nitro group, and p represents an integer of 0 to 2] The cyanine compound according to any one of claims 1 to 3, wherein D is one selected from the following formulas (8) to (12).

[In the formula, Y represents a hydrogen atom, a halogen atom, a phenyl group, a diphenylamino group or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site.] R ₁ and R ₂ are each independently an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an alkoxyalkyl group having 3 to 20 carbon atoms, an alkoxyalkoxyalkyl group having 4 to 20 carbon atoms, a carbon number It is a 2-20 alkenyl group, The cyanine compound as described in any one of Claims 1-4. R < ₁ >, R < ₂ > is a methyl group, n-butyl group, methoxyethyl group, or n-butoxyethyl group each independently, The cyanine compound as described in any one of Claims 1-5. Any of the nitrogen-containing fused heterocycles formed by Q ₁ and Q ₂ in formula (1) according to claim 1 are derived from formula (2), formula (3) or formula (5) according to claim 3. One selected, R ₃ in the formula (2), formula (3) or formula (5) is a halogen atom, and p is an integer of 0 or 1;
R ₁ and R ₂ in formula (1) according to claim 1 are each independently a methyl group, an n-butyl group, a methoxyethyl group or an n-butoxyethyl group;
D is any one of the formula (8), the formula (9), the formula (11), or the formula (12) according to claim 4, and the formula (8), the formula (9), the formula (11), or the formula Y in (12) is a hydrogen atom or a chlorine atom;
X ⁻ is a tris (trifluoromethanesulfonyl) methide anion;
The cyanine compound according to claim 1,
However, the nitrogen-containing fused heterocyclic ring formed by Q ₂ is a replacement of the structural formula of the nitrogen-containing fused heterocyclic ring formed by Q ₁ with the structural formula corresponding to Q ₂ . The following formula (201)

[Wherein, the nitrogen-containing condensed heterocyclic ring formed by Q ₂ is one selected from the following formulas (202) to (204), and R ₄ and R ₅ are each independently a C1-C5 alkyl group or C1 represents -C5 alkoxy C1-C3 alkyl group, _{R 6} is a hydrogen atom, a C1-C5 alkyl group or a phenyl group, Y represents a halogen atom or a phenyl group, X ^- and tris (trifluoromethylsulfonyl) methide anion To express. ]

[Wherein R ₇ represents a hydrogen atom, a halogen atom or a nitro group. ]

The cyanine compound of Claim 1 represented by these. The cyanine compound according to any one of claims 1 to 8, which has maximum absorption in a wavelength region of 400 nm to 1100 nm in methanol. The light absorber using the cyanine compound as described in any one of Claims 1-9. The light absorber according to claim 10, which is for near infrared absorption and / or for improving image characteristics. The optical filter using the light absorber of Claim 10 or 11. A plasma display panel using the optical filter according to claim 12.