WO2015025779A1

WO2015025779A1 - Optical filter and device using optical filter

Info

Publication number: WO2015025779A1
Application number: PCT/JP2014/071311
Authority: WO
Inventors: 勝也長屋
Original assignee: Jsr株式会社
Priority date: 2013-08-20
Filing date: 2014-08-12
Publication date: 2015-02-26
Also published as: KR20160045690A; CN105531608A; TW201518421A; JP6398980B2; CN110669318A; TWI582173B; JPWO2015025779A1; KR102205190B1; CN105531608B

Abstract

The objective of the present invention is to provide: an optical filter which remedies the faults of conventional optical filters such as near-infrared blocking filters and contains a near-infrared absorbing dye that has a sufficient absorption intensity in a wavelength range near 700-750 nm, while having excellent transmittance even in a visible wavelength range on the short wavelength side; and a device which uses this optical filter. An optical filter according to the present invention is characterized by comprising: a transparent resin substrate that contains a compound (A) represented by formula (I); and a near-infrared light reflecting film that is formed on at least one surface of the substrate.

Description

Optical filter and device using optical filter

The present invention relates to an optical filter and an apparatus using the optical filter. Specifically, the present invention relates to an optical filter containing a specific solvent-soluble dye compound, and a solid-state imaging device and a camera module using the optical filter.

A solid-state image pickup device such as a video camera, a digital still camera, or a mobile phone with a camera function uses a CCD or CMOS image sensor, which is a solid-state image pickup device for a color image. Silicon photodiodes that are sensitive to near infrared rays that cannot be sensed by the eyes are used. These solid-state image sensors need to be corrected for visibility so that they appear natural to the human eye. Optical filters that selectively transmit or cut light in a specific wavelength region (for example, near-infrared cut) Filter) is often used.

As such a near-infrared cut filter, those manufactured by various methods are conventionally used. For example, a near-infrared cut filter in which a transparent resin is used as a base material and a near-infrared absorbing dye is contained in the transparent resin is known (see, for example, Patent Document 1), and in particular, a phthalocyanine compound is used as a near-infrared absorbing dye. The near-infrared cut filter used is widely known (see, for example, Patent Document 2).

However, ordinary phthalocyanine compounds often have an absorption maximum wavelength of less than 650 to 700 nm, and the absorption maximum wavelength can be shifted to a wavelength range (700 to 800 nm) that is particularly suitable for use as a solid-state imaging device. With the structure, there is a problem that the visible transmittance on the short wavelength side in the vicinity of 430 to 460 nm is remarkably lowered.

As a technique for shifting the absorption maximum of a phthalocyanine compound by a long wavelength, a technique in which an electron donating group such as an alkoxy group, an alkyl-substituted amino group, or an alkylthio group is introduced into a phthalocyanine ring is generally known (for example, Patent Documents). 3). However, when such a substituent is bonded to the phthalocyanine ring, a charge transfer transition from the unshared electron pair on the substituent to the phthalocyanine ring occurs, and absorption resulting from this transition occurs in the visible region on the short wavelength side. Therefore, the transmittance particularly in the vicinity of 430 to 460 nm is lowered.

Further, it is known that a general phthalocyanine compound is likely to be in an H association state in which rings are stacked in a resin or the like. When the phthalocyanine-based compound undergoes H association, for example, a broad waveform having a weak absorption intensity near the absorption maximum is obtained as in the spectrum described in Example 1 of JP2013-083915A (Patent Document 4). As a result, the optical characteristics required for solid-state imaging device applications may not be achieved.

Japanese Patent Laid-Open No. 6-200113 JP 2013-064975 A Japanese Patent No. 4278923 JP2013-083915A

An object of the present invention is to improve the drawbacks of conventional optical filters such as near-infrared cut filters, and the near-infrared absorbing dye has sufficient absorption intensity in the wavelength region near 700 to 750 nm and is short. An object of the present invention is to provide an optical filter having excellent transmittance in a visible wavelength region on the wavelength side, and an apparatus using the optical filter.

As a result of intensive studies to achieve the above-mentioned problems, the present inventors have achieved a target absorption maximum wavelength and absorption strength in a resin by applying a phthalocyanine compound having a specific structure. The inventors have found that an optical filter having excellent infrared absorption characteristics and visible transmittance can be obtained, and have completed the present invention. Examples of embodiments of the present invention are shown below.

[1] An optical device comprising: a transparent resin substrate containing a compound (A) represented by the following formula (I); and a near-infrared reflective film formed on at least one surface of the substrate. filter.

In the formula (I), M represents two hydrogen atoms, two monovalent metal atoms, a divalent metal atom, or a substituted metal atom containing a trivalent or tetravalent metal atom, and a plurality of R _a independently represents L ^1, and a plurality of R _{b s} independently represent a hydrogen atom, a halogen atom, L ¹ or —SO ₂ —L ² ,
L ¹ is below L ^a, represents L ^b or L ^c, L ² represents a following ^{^{^{L a, L b, L c}}} , L d or L ^e,
(L ^a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms (L ^b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms (L ^c ) an alicyclic hydrocarbon group having 3 to 14 carbon atoms (L ^d ) carbon An aromatic hydrocarbon group having 6 to 14 carbon atoms (L ^e ), a heterocyclic group having 3 to 14 carbon atoms, and the L ^a to ^Le are further an aliphatic hydrocarbon group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Halogen-substituted alkyl group, alicyclic hydrocarbon group having 3 to 14 carbon atoms, aromatic hydrocarbon group having 6 to 14 carbon atoms, heterocyclic group having 3 to 14 carbon atoms, and alkoxy group having 1 to 12 carbon atoms It may have at least one substituent L selected from the group consisting of

[2] In the above formula (I), M is a divalent transition metal, a trivalent or tetravalent metal halide belonging to groups 4 to 12 and 4th to 5th of the periodic table, or 4 R _a is independently an alkyl group having 1 to 10 carbon atoms, a fluorine-substituted alkyl group having 1 to 6 carbon atoms, a cyclopentyl group, or a cyclohexyl group, and R _b is independently a hydrogen atom , A fluorine atom, an alkyl group having 1 to 10 carbon atoms, a cyclopentyl group, a cyclohexyl group, or —SO ₂ —L ² , and L ² is an alkyl group having 1 to 6 carbon atoms and an aromatic carbon atom having 6 to 12 carbon atoms The optical filter according to Item [1], which is a hydrogen group or a heterocyclic group having 3 to 6 carbon atoms.

[3] The transparent resin constituting the transparent resin substrate is a cyclic olefin resin, aromatic polyether resin, polyimide resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, polyamide resin, poly Allylate resin, polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin The optical filter according to Item [1] or [2], which is at least one resin selected from the group consisting of an allyl ester resin and a silsesquioxane resin.

[4] The optical filter according to any one of items [1] to [3], wherein the near-infrared reflective film is formed on both surfaces of the substrate.
[5] The optical filter according to any one of items [1] to [4], which is for a solid-state imaging device.

[6] A solid-state imaging device comprising the optical filter according to any one of items [1] to [5].
[7] A camera module comprising the optical filter according to any one of items [1] to [5].

[8] Compound (A) represented by the following formula (I), cyclic olefin resin, aromatic polyether resin, polyimide resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, polyamide system Resin, polyarylate resin, polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, A resin composition containing at least one resin selected from the group consisting of epoxy resins, allyl ester resins, and silsesquioxane resins.

According to the present invention, it is possible to provide an optical filter that is less dependent on the incident angle, has excellent light resistance, near-infrared absorption characteristics near 700 to 750 nm, and transmittance characteristics in the visible wavelength region.

FIG. 1A is a schematic diagram showing a method for measuring the transmittance when measured from the vertical direction of the optical filter. FIG. 1B is a schematic diagram illustrating a method of measuring the transmittance when measured from an angle of 30 ° with respect to the vertical direction of the optical filter.

Hereinafter, the present invention will be specifically described.
An optical filter according to the present invention includes a transparent resin substrate containing a phthalocyanine compound (compound (A)) represented by a specific structure, and a near-infrared reflective film formed on at least one surface of the substrate. Have

[Transparent resin substrate]
The transparent resin substrate (hereinafter also referred to as “resin substrate”) constituting the optical filter of the present invention may be a single layer or a multilayer (in the case of a multilayer, for example, a cured resin on a base resin substrate). A composition in which an overcoat layer or the like is laminated), and contains at least one compound (A) as a near-infrared absorbing dye, and has an absorption maximum of 700 to 800 nm, more preferably 705 to 750 nm. The transmittance at the absorption maximum wavelength is preferably 10% or less, and more preferably 8% or less. When the absorption maximum wavelength of the substrate and the transmittance at the absorption maximum wavelength are in such a range, the substrate can selectively and efficiently cut near infrared rays, and a near infrared reflecting film on the surface of the transparent resin substrate. When the film is formed, it is possible to reduce the incident angle dependency of the optical characteristics in the visible wavelength to near infrared wavelength region.

Depending on the application of the camera module or the like, in the so-called visible light region having a wavelength of 400 to 700 nm, the average transmittance of the substrate when the thickness of the resin substrate containing the compound (A) is 100 μm is preferably 50% or more, preferably It may be necessary to be 65% or more.

The thickness of the resin substrate can be appropriately selected according to the desired application, and is not particularly limited. However, it is preferable to adjust the substrate so that the incident angle dependency is improved as described above, and more preferably. Is 30 to 250 μm, more preferably 40 to 200 μm, particularly preferably 50 to 150 μm.

When the thickness of the resin substrate is in the above range, the optical filter using the substrate can be reduced in size and weight, and can be suitably used for various applications such as a solid-state imaging device. In particular, when the resinous substrate is used in a lens unit such as a camera module, it is preferable because a low-profile lens unit can be realized.

In addition to the compound (A), the resin substrate further comprises at least one near infrared absorbing dye (X) selected from the group consisting of a squarylium compound, a phthalocyanine compound other than the compound (A), and a cyanine compound. Can be contained. By using such a resin substrate, the incident angle dependency in the visible wavelength region to the near infrared wavelength region can be further reduced, the absorption band waveform can be further sharpened, and a wide viewing angle can be obtained. A filter can be obtained.

The compound (A) and the near-infrared absorbing dye (X) may be contained in the same layer or in different layers. When included in the same layer, for example, a form in which both the compound (A) and the near-infrared absorbing dye (X) are included in the base resin substrate can be mentioned, and when included in separate layers, For example, the form by which the layer containing the said near-infrared absorption pigment | dye (X) is laminated | stacked on the resin-made board | substrates containing a compound (A) can be mentioned.

The compound (A) and the near-infrared absorbing dye (X) are more preferably contained in the same layer. In such a case, the compound (A) and the near-infrared absorbing dye are contained in a case where they are contained in separate layers. It becomes easier to control the content ratio of (X).

<Compound (A)>
The compound (A) is a phthalocyanine compound represented by the following formula (I).

Wherein L ^a ~ L ^e is the total number of carbon atoms including the substituent is preferably respectively 50 or less, still more preferably a few 40 or less carbon atoms, and particularly preferably 30 or less carbon atoms. When the number of carbon atoms is larger than this range, it may be difficult to synthesize the dye, and the absorption intensity per unit weight tends to decrease.

The aliphatic hydrocarbon group L ^a and 1 to 12 carbon atoms in L, such as a methyl group (Me), ethyl (Et), n-propyl group (n-Pr), isopropyl (i-Pr ), N-butyl group (n-Bu), sec-butyl group (s-Bu), tert-butyl group (t-Bu), pentyl group, hexyl group, octyl group, nonyl group, decyl group, dodecyl group, etc. Alkyl groups such as vinyl group, 1-propenyl group, 2-propenyl group, butenyl group, 1,3-butadienyl group, 2-methyl-1-propenyl group, 2-pentenyl group, hexenyl group and octenyl group And alkynyl groups such as ethynyl group, propynyl group, butynyl group, 2-methyl-1-propynyl group, hexynyl group and octynyl group.

Examples of the halogen-substituted alkyl group having 1 to 12 carbon atoms in L ^b and L include, for example, a trichloromethyl group, a trifluoromethyl group, a 1,1-dichloroethyl group, a pentachloroethyl group, a pentafluoroethyl group, a heptachloro group. Mention may be made of propyl and heptafluoropropyl groups.

Examples of the alicyclic hydrocarbon group having 3 to 14 carbon atoms in L ^c and L include, for example, a cycloalkyl group such as a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group and a cyclooctyl group; a norbornane group and an adamantane group And polycyclic alicyclic groups such as

Examples of the aromatic hydrocarbon group having 6 to 14 carbon atoms in L ^d and L include, for example, phenyl group, tolyl group, xylyl group, mesityl group, cumenyl group, 1-naphthyl group, 2-naphthyl group, anthracenyl group, Mention may be made of phenanthryl, acenaphthyl, phenalenyl, tetrahydronaphthyl, indanyl and biphenylyl groups.

Examples of the heterocyclic group having 3 to 14 carbon atoms in ^Le and L include, for example, furan, thiophene, pyrrole, pyrazole, imidazole, triazole, oxazole, oxadiazole, thiazole, thiadiazole, indole, indoline, indolenine, and benzofuran. Benzothiophene, carbazole, dibenzofuran, dibenzothiophene, pyridine, pyrimidine, pyrazine, pyridazine, quinoline, isoquinoline, acridine, morpholine and phenazine.

As the L ^a, preferably a methyl group, an ethyl group, n- propyl group, an isopropyl group, n- butyl group, sec- butyl group, tert- butyl group, a pentyl group, a hexyl group, an octyl group, 4-phenylbutyl 2-cyclohexylethyl, more preferably methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl and hexyl.

L ^b is preferably a trichloromethyl group, a pentachloroethyl group, a trifluoromethyl group, a pentafluoroethyl group, or a 5-cyclohexyl-2,2,3,3-tetrafluoropentyl group, more preferably a trichloromethyl group. A methyl group, a pentachloroethyl group, a trifluoromethyl group, and a pentafluoroethyl group;

L ^c is preferably a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 4-ethylcyclohexyl group, a cyclooctyl group, or a 4-phenylcycloheptyl group, and more preferably a cyclopentyl group, a cyclohexyl group, or a 4-ethylcyclohexyl group. It is.

The L ^d is preferably a phenyl group, 1-naphthyl group, 2-naphthyl group, tolyl group, xylyl group, mesityl group, cumenyl group, 3,5-di-tert-butylphenyl group, 4-cyclopentylphenyl group. 2,3,6-triphenylphenyl group, 2,3,4,5,6-pentaphenylphenyl group, more preferably phenyl group, tolyl group, xylyl group, mesityl group, cumenyl group, 2,3 , 4,5,6-pentaphenylphenyl group.

As the L ^e, preferably furan, thiophene, pyrrole, indole, indoline, indolenine, benzofuran, benzothiophene, consisting morpholine group, more preferably furan, thiophene, pyrrole, consisting morpholine group.

Wherein L ^a ~ L ^e is further halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, have at least one atom or group selected from the group consisting of a phosphate group and an amino group May be. Examples include 4-sulfobutyl, 4-cyanobutyl, 5-carboxypentyl, 5-aminopentyl, 3-hydroxypropyl, 2-phosphorylethyl, 6-amino-2,2-dichloro. Hexyl group, 2-chloro-4-hydroxybutyl group, 2-cyanocyclobutyl group, 3-hydroxycyclopentyl group, 3-carboxycyclopentyl group, 4-aminocyclohexyl group, 4-hydroxycyclohexyl group, 4-hydroxyphenyl group, 2-hydroxynaphthyl group, 4-aminophenyl group, 2,3,4,5,6-pentafluorophenyl group, 4-nitrophenyl group, group consisting of 3-methylpyrrole, 2-hydroxyethoxy group, 3-cyano Propoxy group, 4-fluorobenzoyl group, 2-hydroxyethoxycarbonyl , It may be mentioned 4-cyano-butoxycarbonyl group.

In M, examples of the monovalent metal atom include Li, Na, K, Rb, and Cs.
In M, the divalent metal atoms include Be, Mg, Ca, Ba, Ti, Cr, Mn, Fe, Ru, Co, Rh, Ni, Pd, Pt, Cu, Zn, Cd, Hg, Sn, Pb etc. are mentioned.

In M, the substituted metal atom containing a trivalent metal atom includes Al—F, Al—Cl, Al—Br, Al—I, Ga—F, Ga—Cl, Ga—Br, Ga—I, In -F, In-Cl, In-Br, In-I, Tl-F, Tl-Cl, Tl-Br, Tl-I, Fe-Cl, Ru-Cl, Mn-OH and the like.

In M, the substituted metal atom containing a tetravalent metal atom includes TiF ₂ , TiCl ₂ , TiBr ₂ , TiI ₂ , ZrCl ₂ , HfCl ₂ , CrCl ₂ , SiF ₂ , SiCl ₂ , SiBr ₂ , SiI ₂ , GeF ₂ , GeCl ₂ , GeBr ₂ , GeI ₂ , SnF ₂ , SnCl ₂ , SnBr ₂ , SnI ₂ , Zr (OH) ₂ , Hf (OH) ₂ , Mn (OH) ₂ , Si (OH) ₂ , Ge ( OH) ₂ , Sn (OH) ₂ , TiR ₂ , CrR ₂ , SiR ₂ , GeR ₂ , SnR ₂ , Ti (OR) ₂ , Cr (OR) ₂ , Si (OR) ₂ , Ge (OR) ₂ , Sn (OR) ₂ (R represents an aliphatic group or an aromatic group), TiO, VO, MnO, and the like. Examples of M include groups 4 to 12 in the periodic table, and 4th to 5th cycles. Belongs to divalent transition metals, trivalent or Is preferably a tetravalent metal halide or a tetravalent metal oxide. Among them, Cu, Ni, Co, Zn, TiO and VO are particularly preferable because they can achieve particularly high visible light transmittance and dye stability. More preferred are Cu and VO.

From the viewpoint of ease of synthesis and solubility of the compound (A) in an organic solvent, R _a is independently an alkyl group having 1 to 10 carbon atoms, a fluorine-substituted alkyl group having 1 to 6 carbon atoms, a cyclopentyl group, or A cyclohexyl group is preferred, an alkyl group having 1 to 10 carbon atoms is more preferred, and an alkyl group having 3 to 8 carbon atoms is particularly preferred.

R _b is independently a hydrogen atom, a fluorine atom, an alkyl group having 1 to 10 carbon atoms, a cyclopentyl group, a cyclohexyl group, or —SO ₂ —L from the viewpoint of ease of synthesis and stability of the compound (A). ² (L ² is preferably an alkyl group having 1 to 6 carbon atoms, an aromatic hydrocarbon group having 6 to 12 carbon atoms, or a heterocyclic ring having 3 to 6 carbon atoms), preferably a hydrogen atom or 1 to More preferred is an alkyl group of 6.

A method of synthesizing the compound (A) by a cyclization reaction of a phthalonitrile derivative represented by the following formula (II) is generally known. The resulting phthalocyanine compound is represented by the following formula (II-1) This is a mixture of four isomers such as (II-4). In the present invention, unless otherwise specified, only one isomer is illustrated for one phthalocyanine compound, but the other three isomers can be used similarly. These isomers can be separated and used as necessary, but in the present invention, the isomer mixture is collectively handled.

Specific examples of the compound (A) are not particularly limited as long as the conditions described in the above formula (I) are satisfied. For example, in the following Table 1, which has a basic skeleton represented by the following formula (I-1) And the compounds (a-1) to (a-35) described.

The compound (A) may be synthesized by a generally known method. For example, Japanese Patent No. 4081149, “Phthalocyanine—Chemistry and Function” (IPC, 1997), Japanese Patent Laid-Open No. 2-138382. It can be synthesized with reference to the method described in the publication.

In the resin substrate, the content of the compound (A) in the resin layer is preferably from 0.01 to 5.0 parts by weight, more preferably from 0.1 to 5.0 parts by weight, based on 100 parts by weight of the transparent resin used when the resin substrate is manufactured. It is 02 to 3.5 parts by weight, particularly preferably 0.03 to 2.5 parts by weight. When the content of the compound (A) is within the above range, both good near infrared absorption characteristics and high visible light transmittance can be achieved.

<Near-infrared absorbing dye (X)>
The near-infrared absorbing dye (X) is at least one selected from the group consisting of a squarylium compound, a phthalocyanine compound, and a cyanine compound, and particularly preferably contains a squarylium compound. The absorption maximum wavelength of the near-infrared absorbing dye (X) is preferably 620 nm or more, more preferably 650 nm or more, particularly preferably 670 nm or more, and preferably less than 800 nm, more preferably 750 nm or less, particularly preferably 730 nm or less. In addition, it is desirable that the compound (A) contained at the same time has an absorption maximum on a shorter wavelength side than the absorption maximum wavelength. When the absorption maximum wavelength is in such a wavelength range, the waveform of the absorption band can be further sharpened, the absorption band due to the near-infrared absorbing dye can be sufficiently widened, and the incident angle dependent improvement performance and ghosting can be improved. A reduction effect can be achieved.

In the resin substrate, the content of the near-infrared absorbing dye (X) in the resin layer is preferably 0.01 to 5.0 parts by weight, more preferably 100 parts by weight of the transparent resin used when the resin substrate is manufactured. Is 0.02 to 3.5 parts by weight, particularly preferably 0.03 to 2.5 parts by weight. When the content of the near-infrared absorbing dye is within the above range, both good near-infrared absorption characteristics and high visible light transmittance can be achieved.

《Squaryllium compound》
The squarylium-based compound preferably includes at least one selected from the group consisting of a squarylium-based compound represented by the formula (III-1) and a squarylium-based compound represented by the formula (III-2).

In the formula (III-1), R ^m , R ⁿ and Y satisfy the following condition (i) or (ii).
Condition (i)
A plurality of R ^m each independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, a phosphoric acid group, —L ¹ or —NR ^e R ^f group. R ^e and R ^f each independently represents a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d, or -L ^e .

A plurality of R ⁿ each independently represents a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, a nitro group, a carboxy group, a phosphoric acid group, —L ¹ or —NR ^g R ^h group. R ^g and R ^h are each independently a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d , -L ^e or -C (O) R ⁱ group (R ⁱ is -L ^a , Represents -L ^b , -L ^c , -L ^d or -L ^e ).

A plurality of Y each independently represents a —NR ^j R ^k group. R ^j and R ^k each independently represents a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d, or -L ^e .
Wherein ^{^{^{L 1, L a, L b}}} , L c, L d, L e is, L ¹ defined in independent to the formula ^{(I), L a, L} b, L c, L d, and L ^e It is synonymous.

Condition (ii)
At least one of two R ^m on one benzene ring is bonded to Y on the same benzene ring to form a heterocycle having 5 or 6 member atoms containing at least one nitrogen atom; the heterocyclic ring may have a substituent, R ^m which is not involved in the formation of R ⁿ and the heterocyclic ring is the same meaning as R ⁿ and R ^m of the independently (i).

Wherein (III-2), X is, -O -, - S -, - Se -, - N (R c) - or -C (R ^{^d} R ^d) - a represents; plural R ^c is respectively Each independently represents ^a hydrogen atom, -L ^a , -L ^b , -L ^c , -L ^d or -L ^e ; a plurality of R ^{d s} independently represent a hydrogen atom, a halogen atom, a sulfo group, a hydroxyl group, a cyano group, Represents a nitro group, a carboxy group, a phosphate group, —L ¹ or —NR ^e R ^f group, and adjacent R ^d groups may be linked to form an optionally substituted ring; L ^a ~ L ^e, L ¹ has the same meaning as L ^a ~ L ^e defined by formula (I), R ^e and R ^f have the same meanings as R ^e and R ^f of the (i).

The left and right substituents bonded to the central four-membered ring of the squarylium-based compound may be the same or different, but it is preferable that they are the same because synthesis is easier.
The squarylium compound may be synthesized by a generally known method, for example, a method described in JP-A-1-228960, JP-A-2001-40234, JP-A-3196383, or the like. Etc. and can be synthesized.

《Phthalocyanine compound》
As the phthalocyanine compound, those having an arbitrary structure other than the compound (A) can be used. For example, Japanese Patent No. 4081149 and “phthalocyanine -chemistry and function” (IPC, 1997). In the year).

<Cyanine compounds>
As the cyanine compound, a compound having a generally known structure can be used, and for example, it can be synthesized by a method described in JP-A-2009-108267.

<Transparent resin>
The resin substrate contains a transparent resin and the compound (A).
The transparent resin is not particularly limited as long as it does not impair the effects of the present invention. For example, it ensures thermal stability and moldability to a film, and dielectrics are formed by high-temperature deposition performed at a deposition temperature of 100 ° C. or higher. For example, a resin having a glass transition temperature (Tg) of preferably 110 to 380.degree. C., more preferably 110 to 370.degree. C., and still more preferably 120 to 360.degree. Further, it is particularly preferable that the glass transition temperature of the resin is 140 ° C. or higher because a film capable of depositing a dielectric multilayer film at a higher temperature can be obtained.

As the transparent resin, when a resin plate made of the resin having a thickness of 0.1 mm is formed, the total light transmittance (JIS K7105) of the resin plate is preferably 75 to 95%, more preferably 78 to 95. %, Particularly preferably 80 to 95% of the resin can be used. If a resin having a total light transmittance in such a range is used, the resulting substrate exhibits good transparency as an optical film.

The weight average molecular weight (Mw) in terms of polystyrene measured by a gel permeation chromatography (GPC) method of the transparent resin is usually 15,000 to 350,000, preferably 30,000 to 250,000. The average molecular weight (Mn) is usually 10,000 to 150,000, preferably 20,000 to 100,000.

Examples of the transparent resin include cyclic olefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide (aramid) resins, polyarylate resins, polysulfones. Resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate (PEN) resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin, allyl Examples include ester resins and silsesquioxane resins.

≪Cyclic olefin resin≫
The cyclic olefin-based resin is obtained from at least one monomer selected from the group consisting of a monomer represented by the following formula (X ₀ ) and a monomer represented by the following formula (Y ₀ ). A resin and a resin obtained by hydrogenating the resin are preferable.

In the formula (X ₀ ), R ^x1 to R ^x4 each independently represents an atom or group selected from the following (i ′) to (ix ′), and k ^x , ^mx and p ^x are each independently 0 Or represents a positive integer.
(I ′) a hydrogen atom (ii ′) a halogen atom (iii ′) a trialkylsilyl group (iv ′) having a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom,
A substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms (v ′) a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms (vi ′) polar group (excluding (iv ′))
(Vii ′) an alkylidene group formed by bonding R ^x1 and R ^x2 or R ^x3 and R ^x4 to each other (provided that R ^x1 to R ^x4 not involved in the bonding are independently the above (i ′ )-(Vi ′) represents an atom or group selected from.
(Viii ′) R ^x1 and R ^x2 or R ^x3 and R ^x4 are bonded to each other to form a monocyclic or polycyclic hydrocarbon ring or heterocyclic ring (provided that R ^x1 to R which are not involved in the bond) ^x4 each independently represents an atom or group selected from (i ′) to (vi ′).
(Ix ′) A monocyclic hydrocarbon ring or heterocycle formed by bonding R ^x2 and R ^x3 to each other (provided that R ^x1 and R ^x4 not involved in the bonding are each independently the above (i Represents an atom or group selected from ') to (vi').

In the formula (Y ₀ ), R ^y1 and R ^y2 each independently represents an atom or group selected from the above (i ′) to (vi ′), or R ^y1 and R ^y2 are bonded to each other formed monocyclic or polycyclic alicyclic hydrocarbon, an aromatic hydrocarbon or heterocyclic, k ^y and p ^y are each independently 0 or a positive integer.

≪Aromatic polyether resin≫
The aromatic polyether-based resin preferably has at least one structural unit selected from the group consisting of a structural unit represented by the following formula (1) and a structural unit represented by the following formula (2).

In formula (1), R ¹ to R ⁴ each independently represents a monovalent organic group having 1 to 12 carbon atoms, and a to d each independently represent an integer of 0 to 4.

Wherein ^{(2), R 1 ~ R} 4 and a ~ d are the same as R ¹ ~ R ⁴ and a ~ d of each in independently on the formula (1), Y a single bond, -SO ₂ -Or> C = O, R ⁷ and R ⁸ each independently represent a halogen atom, a monovalent organic group having 1 to 12 carbon atoms or a nitro group, and g and h each independently represent 0 to 4 And m represents 0 or 1. However, when m is 0, R ⁷ is not a cyano group.

The aromatic polyether resin further has at least one structural unit selected from the group consisting of a structural unit represented by the following formula (3) and a structural unit represented by the following formula (4). Is preferred.

In the formula (3), R ⁵ and R ⁶ each independently represent a monovalent organic group having 1 to 12 carbon atoms, Z represents a single bond, —O—, —S—, —SO ₂ —,> C═O, —CONH—, —COO— or a divalent organic group having 1 to 12 carbon atoms, e and f each independently represent an integer of 0 to 4, and n represents 0 or 1.

In the formula (4), R ⁷ , R ⁸ , Y, m, g and h are each independently synonymous with R ⁷ , R ⁸ , Y, m, g and h in the formula (2), and R ⁵ , R ⁶ , Z, n, e and f are independently the same as R ⁵ , R ⁶ , Z, n, e and f in the formula (3).

≪Polyimide resin≫
The polyimide resin is not particularly limited as long as it is a polymer compound containing an imide bond in a repeating unit. For example, the polyimide resin is synthesized by a method described in JP-A-2006-199945 and JP-A-2008-163107. can do.

≪Fluorene polycarbonate resin≫
The fluorene polycarbonate resin is not particularly limited as long as it is a polycarbonate resin containing a fluorene moiety, and can be synthesized by, for example, a method described in JP-A-2008-163194.

≪Fluorene polyester resin≫
The fluorene polyester resin is not particularly limited and may be any polyester resin containing a fluorene moiety. For example, the fluorene polyester resin can be synthesized by a method described in JP 2010-285505 A or JP 2011-197450 A. it can.

≪Fluorinated aromatic polymer resin≫
The fluorinated aromatic polymer-based resin is not particularly limited, but at least one selected from the group consisting of an aromatic ring having at least one fluorine, an ether bond, a ketone bond, a sulfone bond, an amide bond, an imide bond, and an ester bond. Any polymer containing a repeating unit containing one bond may be used, and for example, it can be synthesized by the method described in JP-A-2008-181121.

≪Commercial product≫
The following commercial products etc. can be mentioned as a commercial item of transparent resin. Examples of commercially available cyclic olefin-based resins include Arton manufactured by JSR Corporation, ZEONOR manufactured by Zeon Corporation, APEL manufactured by Mitsui Chemicals, Inc., and TOPAS manufactured by Polyplastics Corporation. Examples of commercially available polyethersulfone resins include Sumika Excel PES manufactured by Sumitomo Chemical Co., Ltd. Examples of commercially available polyimide resins include Neoprim L manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available polycarbonate resins include Pure Ace manufactured by Teijin Limited. Examples of commercially available fluorene polycarbonate resins include Iupizeta EP-5000 manufactured by Mitsubishi Gas Chemical Co., Ltd. Examples of commercially available fluorene polyester resins include OKP4HT manufactured by Osaka Gas Chemical Co., Ltd. As a commercial item of acrylic resin, there can be cited NIPPON CATALYST ACRYVIEWER Co., Ltd. Examples of commercially available silsesquioxane resins include Silplus manufactured by Nippon Steel Chemical Co., Ltd.

<Other ingredients>
The resin substrate is a dye that absorbs near infrared rays other than the antioxidant, the near ultraviolet absorber, the compound (A) and the near infrared absorbing dye (X) (hereinafter “ It may also contain additives such as “other near-infrared absorbing dyes”), fluorescence quenchers, and metal complex compounds. Moreover, when manufacturing a resin-made board | substrate by cast shaping | molding mentioned later, manufacture of a resin-made board | substrate can be made easy by adding a leveling agent and an antifoamer. These other components may be used alone or in combination of two or more.

Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,2′-dioxy-3,3′-di-t-butyl-5,5′-dimethyldiphenylmethane, and And tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane.

Examples of the near ultraviolet absorber include azomethine compounds, indole compounds, benzotriazole compounds, and triazine compounds.
Examples of the other near infrared absorbing dyes include dithiol dyes, diimonium dyes, porphyrin dyes, and croconium dyes. The structures of these dyes are not particularly limited, and generally known ones can be used as long as the effects of the present invention are not impaired.

Note that these additives may be mixed with a resin or the like when a resin substrate is manufactured, or may be added when a resin is manufactured. The addition amount is appropriately selected according to the desired properties, but is usually 0.01 to 5.0 parts by weight, preferably 0.05 to 2.0 parts by weight, based on 100 parts by weight of the resin. Part.

<Manufacturing method of resin substrate>
The resin substrate can be formed by, for example, melt molding or cast molding, and if necessary, is manufactured by a method of coating a coating agent such as an antireflection agent, a hard coating agent and / or an antistatic agent after molding. be able to.

≪Melt molding≫
The resin substrate is a method of melt-molding pellets obtained by melt-kneading a resin and a near-infrared absorbing dye; a method of melt-molding a resin composition containing a resin and a near-infrared absorbing dye; or It can be produced by a method of melt-molding pellets obtained by removing a solvent from a resin composition containing a near-infrared absorbing dye, a resin and a solvent. Examples of the melt molding method include injection molding, melt extrusion molding, and blow molding.

≪Cast molding≫
The resin substrate is formed by casting a resin composition containing a near-infrared absorbing dye, a resin and a solvent on a suitable base material to remove the solvent; and a curable resin composition containing a near-infrared absorbing dye and a resin. It can also be produced by a method of applying on a suitable substrate, drying and curing, and the like.

Examples of the substrate include a glass plate, a steel belt, a steel drum, and a transparent resin (for example, a polyester film and a cyclic olefin resin film).
The resin substrate can be obtained by peeling from the base material, and unless the effect of the present invention is impaired, the laminate of the base material and the coating film is not peeled from the base material. It is good.

Further, the optical component such as glass plate, quartz or transparent plastic is coated with the resin composition and the solvent is dried, or the curable composition is coated and cured and dried. A resin substrate can also be formed directly on the component.

The amount of residual solvent in the resin substrate obtained by the above method should be as small as possible. Specifically, the amount of the residual solvent is preferably 3% by weight or less, more preferably 1% by weight or less, and still more preferably 0.5% by weight or less with respect to the weight of the resin substrate. When the amount of residual solvent is in the above range, a resin substrate can be obtained in which the deformation and characteristics are hardly changed and a desired function can be easily exhibited.

[Near-infrared reflective film]
The near-infrared reflective film constituting the optical filter of the present invention is a film having the ability to reflect near-infrared light. In the present invention, the near-infrared reflective film may be provided on one side of the resin substrate or on both sides. When it is provided on one side, it is excellent in production cost and manufacturability, and when it is provided on both sides, an optical filter having high strength and less warpage can be obtained. When the optical filter is applied to a solid-state imaging device, it is preferable that the optical filter has a smaller warp. Therefore, it is preferable to provide a near-infrared reflective film on both surfaces of the resin substrate.

Examples of the near-infrared reflective film include an aluminum vapor-deposited film, a noble metal thin film, a resin film in which metal oxide fine particles mainly containing indium oxide and containing a small amount of tin oxide are dispersed, a high refractive index material layer, and a low refractive index material. A dielectric multilayer film in which layers are alternately stacked can be mentioned. Among the near-infrared reflective films, a dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately laminated is more preferable.

As the material constituting the high refractive index material layer, a material having a refractive index of 1.7 or more can be used, and a material having a refractive index of usually 1.7 to 2.5 is selected. Examples of such materials include titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, or indium oxide, and the like, and titanium oxide, tin oxide. And / or those containing a small amount of cerium oxide or the like (for example, 0 to 10% by weight with respect to the main component).

As the material constituting the low refractive index material layer, a material having a refractive index of 1.6 or less can be used, and a material having a refractive index of usually 1.2 to 1.6 is selected. Examples of such materials include silica, alumina, lanthanum fluoride, magnesium fluoride, and sodium hexafluoride sodium.

The method for laminating the high refractive index material layer and the low refractive index material layer is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, a dielectric in which high-refractive index material layers and low-refractive index material layers are alternately laminated directly on a resin substrate by CVD, sputtering, vacuum deposition, ion-assisted deposition, or ion plating. A body multilayer film can be formed.

The thickness of each of the high refractive index material layer and the low refractive index material layer is usually preferably from 0.1λ to 0.5λ, where λ (nm) is the near infrared wavelength to be blocked. The value of λ (nm) is, for example, 700 to 1400 nm, preferably 750 to 1300 nm. When the thickness is within this range, the optical film thickness, the high refractive index material layer, and the low refractive index, where the product (n × d) of the refractive index (n) and the film thickness (d) is calculated by λ / 4. The thickness of each layer of the material layer becomes almost the same value, and there is a tendency that the blocking / transmission of a specific wavelength can be easily controlled from the relationship between the optical characteristics of reflection / refraction.

The total number of high refractive index material layers and low refractive index material layers in the dielectric multilayer film is preferably 5 to 60 layers, and more preferably 10 to 50 layers as a whole.

[Other functional membranes]
In the optical filter of the present invention, the surface hardness of the resin substrate or near-infrared reflective film is between the resin substrate and the near-infrared reflective film such as a dielectric multilayer film within a range not impairing the effects of the present invention. Functional films such as an antireflection film, a hard coat film, and an antistatic film can be provided as appropriate for the purpose of improvement, chemical resistance improvement, antistatic and scratch removal.

For the purpose of improving the adhesion between the resin substrate and the functional film and / or near-infrared reflective film, and the adhesion between the functional film and the near-infrared reflective film, the surface of the resin substrate or functional film is subjected to corona treatment, plasma treatment, etc. The surface treatment may be performed.

[Characteristics etc. of optical filter]
The optical filter of the present invention has the resin substrate. For this reason, the optical filter of the present invention has excellent transmittance characteristics and is not restricted when used. In addition, since the compound (A) contained in the resin substrate has an absorption maximum at a wavelength of 700 to 800 nm, it can efficiently absorb near-infrared light. When combined with the near-infrared reflective film, the incident angle is increased. An optical filter with less dependency can be obtained.

By using the resin substrate for an optical filter such as a near-infrared cut filter, a wavelength value (Xa) at which the transmittance is 50% when measured from the vertical direction of the optical filter in the wavelength range of 560 to 800 nm. The absolute value of the difference from the wavelength value (Xb) at which the transmittance is 50% when measured from an angle of 30 ° with respect to the vertical direction of the optical filter, and the optical filter in the wavelength range of 560 to 800 nm The wavelength value (Za) at which the transmittance is 10% when measured from the vertical direction and the wavelength value at which the transmittance is 10% when measured from an angle of 30 ° with respect to the vertical direction of the optical filter. The absolute value of the difference from (Zb) becomes small, the incident angle dependence of the absorption wavelength is small, and an optical filter having a wide viewing angle can be obtained even near the bottom of the transmission wavelength region. In the optical filter of the present invention, the absolute value of the difference between (Xa) and (Xb) is preferably less than 20 nm, more preferably less than 15 nm, particularly preferably less than 10 nm, and the difference between (Za) and (Zb) The absolute value is preferably 18 nm or less, particularly preferably 15 nm or less.

When the optical filter is used for a solid-state image sensor, it is preferable that the visible light transmittance is higher. Particularly in recent years, there has been a strong demand for higher image quality in camera modules, and in order to improve imaging sensitivity and color reproducibility, it is necessary to increase the transmittance on the short wavelength side of wavelengths 430 to 460 nm. Specifically, the average transmittance at a wavelength of 430 to 460 nm is preferably 81% or more, more preferably 83% or more, and particularly preferably 85% or more. Similarly, the average transmittance at wavelengths of 461 to 580 nm is preferably higher, preferably 85% or more, more preferably 88% or more, and particularly preferably 90% or more. When the average transmittance is within this range in each wavelength region, excellent imaging sensitivity and color reproducibility can be achieved when used as a solid-state imaging device.

When the optical filter is used for a solid-state imaging device, it is preferable that the transmittance in the near infrared wavelength region is low. In particular, it is known that the light receiving sensitivity of the solid-state imaging device is relatively high in the wavelength region of 800 to 1000 nm. By reducing the transmittance in this wavelength region, it is effective to correct the visibility of the camera image and the human eye. And excellent color reproducibility can be achieved. The average transmittance at a wavelength of 800 to 1000 nm is preferably 15% or less, more preferably 10% or less, and particularly preferably 5% or less. When the average transmittance at a wavelength of 800 to 1000 nm is in this range, it is preferable because near infrared rays can be sufficiently cut and excellent color reproducibility can be achieved.

[Application of optical filter]
The optical filter of the present invention has a wide viewing angle and has excellent near-infrared cutting ability and the like. Therefore, it is useful for correcting the visibility of a solid-state imaging device such as a CCD or CMOS image sensor of a camera module. In particular, digital still cameras, mobile phone cameras, digital video cameras, personal computer cameras, surveillance cameras, automotive cameras, TVs, in-vehicle devices for car navigation systems, personal digital assistants, video game machines, portable game machines, fingerprint authentication Useful for system devices, digital music players, etc. Furthermore, it is also useful as a heat ray cut filter attached to a glass plate of an automobile or a building.

[Solid-state imaging device]
The solid-state imaging device of the present invention includes the optical filter of the present invention. Here, the solid-state imaging device is an image sensor including a solid-state imaging device such as a CCD or a CMOS image sensor, and specifically includes a digital still camera, a mobile phone camera, a digital video camera, and the like. For example, the camera module of the present invention includes the optical filter of the present invention.

Hereinafter, the present invention will be described more specifically based on examples, but the present invention is not limited to these examples. “Parts” means “parts by weight” unless otherwise specified. Moreover, the measurement method of each physical property value and the evaluation method of the physical property are as follows.

<Molecular weight>
The molecular weight of the resin was measured by the following method (a) or (b) in consideration of the solubility of each resin in a solvent.
(A) Weight average molecular weight in terms of standard polystyrene using a gel permeation chromatography (GPC) apparatus (150C type, column: H type column manufactured by Tosoh Corporation, developing solvent: o-dichlorobenzene) manufactured by WATERS (Mw) and number average molecular weight (Mn) were measured.
(B) Standard polystyrene equivalent weight average molecular weight (Mw) and number average molecular weight (Mn) were measured using a GPC apparatus (HLC-8220 type, column: TSKgelα-M, developing solvent: THF) manufactured by Tosoh Corporation.

In addition, about the resin synthesize | combined in the resin synthesis example 3 mentioned later, the logarithmic viscosity was measured by the following method (c) instead of the molecular weight measurement by the said method.
(C) A part of the polyimide resin solution was added to anhydrous methanol to precipitate the polyimide resin, and filtered to separate from the unreacted monomer. 0.1 g of polyimide obtained by vacuum drying at 80 ° C. for 12 hours is dissolved in 20 mL of N-methyl-2-pyrrolidone, and the logarithmic viscosity (μ) at 30 ° C. is obtained by the following formula using a Canon-Fenske viscometer. Asked.

_{μ = {ln (t s /} t 0)} / C
t ₀ : Flowing time of solvent t _s : Flowing time of dilute polymer solution C: 0.5 g / dL
<Glass transition temperature (Tg)>
Using a differential scanning calorimeter (DSC6200) manufactured by SII Nano Technologies, Inc., the rate of temperature increase was measured at 20 ° C. per minute under a nitrogen stream.

<Spectral transmittance>
The transmittance at the absorption maximum wavelength and the absorption maximum wavelength of the resin substrate, the transmittance at each wavelength region of the optical filter, (Xa), (Xb), (Za) and (Zb) are spectroscopic products manufactured by Hitachi High-Technologies Corporation. Measurement was performed using a photometer (U-4100).

Here, with respect to the transmittance when measured from the vertical direction of the optical filter, the light transmitted perpendicular to the filter was measured as shown in FIG. Further, with respect to the transmittance when measured from an angle of 30 ° with respect to the vertical direction of the optical filter, light transmitted at an angle of 30 ° with respect to the vertical direction of the filter was measured as shown in FIG.

In addition, this transmittance | permeability was measured using this spectrophotometer on the conditions that light injects perpendicularly with respect to a board | substrate and a filter except the case where (Xb) and (Zb) are measured. When measuring (Xb) or (Zb), it is measured using the spectrophotometer under the condition that light is incident at an angle of 30 ° with respect to the vertical direction of the filter.

<Light resistance evaluation of near-infrared absorbing dye>
The resin substrate was exposed to an indoor fluorescent lamp (illuminance of 1000 lux) for 500 hours, and the light resistance (environmental light resistance) of the near-infrared absorbing dye contained in the resin was evaluated. The light resistance is fluorescence at a wavelength with the highest absorption intensity of the resin substrate (hereinafter referred to as “λa”. When the resin substrate has a plurality of absorption maxima, λa is a wavelength with the highest absorption intensity among them). The pigment residual ratio (%) was calculated from the change in absorbance before and after exposure to the lamp and evaluated. The dye residual ratio after exposure with a fluorescent lamp for 500 hours is preferably 85% or more, more preferably 90% or more, and particularly preferably 95% or more.

[Synthesis example]
The compound (A), squarylium compound, phthalocyanine compound and cyanine compound used in the following examples were synthesized by a generally known method. Examples of the general synthesis method include, for example, Japanese Patent No. 336697, Japanese Patent No. 2846091, Japanese Patent No. 2864475, Japanese Patent No. 3703869, Japanese Patent Laid-Open No. 60-228448, Japanese Patent Laid-Open No. 1-146846, JP-A-1-228960, JP-A-4081149, JP-A-63-124054, “Phthalocyanine—Chemistry and Function” (IPC, 1997), JP-A-2007-169315, JP2009. -108267, JP2010-241873, JP3699464, JP4740631, and the like.

<Resin synthesis example 1>
8-methyl-8-methoxycarbonyltetracyclo represented by the following formula (a) [4.4.0.1 ^2,5 . 1 ^7,10 ] Dodec-3-ene (hereinafter also referred to as “DNM”) 100 parts, 1-hexene (molecular weight regulator) 18 parts, and toluene (ring-opening polymerization solvent) 300 parts nitrogen-substituted reaction The vessel was charged and the solution was heated to 80 ° C. Next, 0.2 parts of a toluene solution of triethylaluminum (0.6 mol / liter) as a polymerization catalyst and a toluene solution of methanol-modified tungsten hexachloride (concentration 0.025 mol / liter) were added to the solution in the reaction vessel. 9 parts was added and this solution was heated and stirred at 80 ° C. for 3 hours to cause a ring-opening polymerization reaction to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%.

1,000 parts of the ring-opening polymer solution thus obtained was charged into an autoclave, and 0.12 part of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution. Then, the hydrogenation reaction was performed by heating and stirring for 3 hours under the conditions of a hydrogen gas pressure of 100 kg / cm ² and a reaction temperature of 165 ° C. After cooling the obtained reaction solution (hydrogenated polymer solution), the hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover the coagulated product, and dried to obtain a hydrogenated polymer (hereinafter also referred to as “resin A”). The obtained resin A had a number average molecular weight (Mn) of 32,000, a weight average molecular weight (Mw) of 137,000, and a glass transition temperature (Tg) of 165 ° C.

<Resin synthesis example 2>
In a 3 L four-necked flask, 35.12 g (0.253 mol) of 2,6-difluorobenzonitrile, 87.60 g (0.250 mol) of 9,9-bis (4-hydroxyphenyl) fluorene, 41.46 g of potassium carbonate ( 0.300 mol), 443 g of N, N-dimethylacetamide (hereinafter also referred to as “DMAc”) and 111 g of toluene were added. Subsequently, a thermometer, a stirrer, a three-way cock with a nitrogen introduction tube, a Dean-Stark tube and a cooling tube were attached to the four-necked flask. Next, after the atmosphere in the flask was replaced with nitrogen, the resulting solution was reacted at 140 ° C. for 3 hours, and water produced was removed from the Dean-Stark tube as needed. When no more water was observed, the temperature was gradually raised to 160 ° C. and reacted at that temperature for 6 hours. After cooling to room temperature (25 ° C.), the produced salt was removed with a filter paper, the filtrate was poured into methanol for reprecipitation, and the filtrate (residue) was isolated by filtration. The obtained filtrate was vacuum-dried overnight at 60 ° C. to obtain a white powder (hereinafter also referred to as “resin B”) (yield 95%). The obtained resin B had a number average molecular weight (Mn) of 75,000, a weight average molecular weight (Mw) of 188,000, and a glass transition temperature (Tg) of 285 ° C.

<Resin synthesis example 3>
In a 500 mL five-necked flask equipped with a thermometer, stirrer, nitrogen inlet tube, dropping funnel with side tube, Dean-Stark tube and condenser tube, 1,4-bis (4-amino-α, α -Dimethylbenzyl) benzene (27.66 g, 0.08 mol) and 4,4′-bis (4-aminophenoxy) biphenyl (7.38 g, 0.02 mol) were added, and γ-butyrolactone (68.65 g) and N, It was dissolved in 17.16 g of N-dimethylacetamide. The obtained solution was cooled to 5 ° C. using an ice-water bath, and while maintaining the same temperature, 22.62 g (0.1 mol) of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and an imidization catalyst As a result, 0.50 g (0.005 mol) of triethylamine was added all at once. After completion of the addition, the temperature was raised to 180 ° C. and refluxed for 6 hours while distilling off the distillate as needed. After completion of the reaction, the reaction solution was air-cooled until the internal temperature reached 100 ° C., diluted by adding 143.6 g of N, N-dimethylacetamide, cooled with stirring, and 264.16 g of a polyimide resin solution having a solid content concentration of 20% by weight. Got. A part of this polyimide resin solution was poured into 1 L of methanol to precipitate the polyimide. The polyimide separated by filtration was washed with methanol and dried in a vacuum dryer at 100 ° C. for 24 hours to obtain a white powder (hereinafter also referred to as “resin C”). The IR spectrum of the obtained resin C was measured, 1704 cm ^-1 characteristic of imido group, absorption of 1770 cm ^-1 were observed. Resin C had a glass transition temperature (Tg) of 310 ° C. and a logarithmic viscosity of 0.87.

<Resin synthesis example 4>
9.167 kg (20.90 mol) of 9,9-bis {4- (2-hydroxyethoxy) phenyl} fluorene, 4.585 kg (20.08 mol) of bisphenol A, 9.000 kg (42.01 mol) of diphenyl carbonate , And 0.02066 kg (2.459 × 10 ⁻⁴ mol) of sodium bicarbonate were placed in a 50 L reactor equipped with a stirrer and a distillation apparatus, and heated to 215 ° C. over 1 hour under a nitrogen atmosphere under 760 Torr. Stir. Thereafter, the degree of vacuum was adjusted to 150 Torr over 15 minutes, and the mixture was held at 215 ° C. and 150 Torr for 20 minutes to conduct a transesterification reaction. Next, the temperature was raised to 240 ° C. at a rate of 37.5 ° C./Hr, held at 240 ° C. and 150 Torr for 10 minutes, adjusted to 120 Torr over 10 minutes, held at 240 ° C. and 120 Torr for 70 minutes, Further, the pressure was adjusted to 100 Torr over 10 minutes and held at 240 ° C. and 100 Torr for 10 minutes. Thereafter, the polymerization reaction was carried out by stirring for 10 minutes under the conditions of 240 ° C. and 1 Torr or less at 40 ° C. over 1 Torr. After completion of the reaction, nitrogen was introduced into the reactor to be in a pressurized state, and the produced polycarbonate resin (hereinafter also referred to as “resin D”) was extracted while being pelletized. The obtained resin D had a weight average molecular weight of 41,000 and a glass transition temperature (Tg) of 152 ° C.

<Resin synthesis example 5>
To the reactor, 0.8 mol of 9,9-bis {4- (2-hydroxyethoxy) -3,5-dimethylphenyl} fluorene, 2.2 mol of ethylene glycol and 1.0 mol of dimethyl isophthalate were added and stirred. The mixture was gradually heated and melted to conduct a transesterification reaction. Next, 20 × 10 ⁻⁴ mol of germanium oxide was added, and ethylene glycol was removed while gradually increasing the temperature and reducing the pressure until reaching 290 ° C. and 1 Torr or less. Thereafter, the contents were taken out of the reactor to obtain pellets of polyester resin (hereinafter also referred to as “resin E”). The obtained resin E had a number average molecular weight of 40,000 and a glass transition temperature of 145 ° C.

<Resin synthesis example 6>
A reactor equipped with a thermometer, a cooling pipe, a gas introduction pipe and a stirrer was charged with 16.74 parts of 4,4′-bis (2,3,4,5,6-pentafluorobenzoyl) diphenyl ether (BPDE), 9, 10.5 parts of 9-bis (4-hydroxyphenyl) fluorene (HF), 4.34 parts of potassium carbonate and 90 parts of DMAc were charged. The mixture was warmed to 80 ° C. and reacted for 8 hours. After completion of the reaction, the reaction solution was added into a 1% aqueous acetic acid solution with vigorous stirring with a blender. The precipitated reaction product was separated by filtration, washed with distilled water and methanol, and then dried under reduced pressure to obtain a fluorinated polyether ketone (hereinafter also referred to as “resin F”). The obtained resin F had a number average molecular weight of 71,000 and a glass transition temperature (Tg) of 242 ° C.

[Example 1]
In a container, 100 parts by weight of the resin A obtained in Resin Synthesis Example 1, 0.06 parts by weight of the compound (a-12) described in Table 1 above as the compound (A) (absorption maximum wavelength 736 nm in dichloromethane), And methylene chloride was added to obtain a solution having a resin concentration of 20% by weight. Subsequently, the obtained solution was cast on a smooth glass plate, dried at 20 ° C. for 8 hours, and then peeled off from the glass plate. The peeled coating film was further dried at 100 ° C. under reduced pressure for 8 hours to obtain a substrate having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm.

The spectral transmittance of this substrate was measured, and the absorption maximum wavelength of the resin substrate, the transmittance at the absorption maximum wavelength, and the dye residual ratio after the light resistance test were determined to be 736 nm, 2%, and 100%, respectively. . The results are shown in Table 2.

Subsequently, on one side of the obtained substrate, a multilayer deposited film reflecting a near infrared ray at a deposition temperature of 100 ° C. [silica (SiO ₂ : film thickness 83 to 199 nm) layer and titanium oxide (TiO ₂ : film thickness 101 to 125 nm) A multilayer deposited film [silica (SiO ₂ : film thickness 77) reflecting near infrared rays at a deposition temperature of 100 ° C. is formed on the other surface of the substrate. To 189 nm) layers and titania (TiO ₂ : film thickness 84 to 118 nm) layers are alternately laminated, and the number of laminations is 26] to obtain an optical filter having a thickness of 0.105 mm. The spectral transmittance of this optical filter was measured, and the optical characteristics in each wavelength region were evaluated.

The average transmittance at wavelengths 430 to 460 nm is 87%, the average transmittance at wavelengths 461 to 580 nm is 91%, the average transmittance at wavelengths 800 to 1000 nm is 1% or less, and the absolute value | Xa−Xb | Was 5 nm and | Za-Zb | was 12 nm. The results are shown in Table 2.

[Example 2] to [Example 17] and [Comparative Example 1] to [Comparative Example 5]
In Example 1, an optical filter having a thickness of 0.105 mm was produced in the same manner as in Example 1 except that the transparent resin, near-infrared absorbing dye, solvent, and film drying conditions shown in Table 2 were employed. The evaluation results are shown in Table 2. In Table 2, the number of added parts of the resin is 100 parts by weight, and the concentration of the resin solution is 20% by weight. The various compounds used in the examples and comparative examples are as follows.

<Transparent resin>
Resin A: Cyclic olefin resin (resin synthesis example 1)
Resin B: Aromatic polyether resin (resin synthesis example 2)
Resin C: Polyimide resin (resin synthesis example 3)
Resin D: Fluorene polycarbonate resin (resin synthesis example 4)
Resin E: Fluorene polyester resin (resin synthesis example 5)
Resin F: Fluorinated polyether ketone (resin synthesis example 6)
Resin G: Cyclic olefin resin “Zeonor 1420R” (manufactured by Nippon Zeon Co., Ltd.)
Resin H: Cyclic olefin resin “APEL # 6015” (manufactured by Mitsui Chemicals, Inc.)
Resin I: Polycarbonate resin “Pure Ace” (manufactured by Teijin Limited)
Resin J: Polyethersulfone resin “Sumilite FS-1300”
(Sumitomo Bakelite Co., Ltd.)
Resin K: Heat-resistant acrylic resin "Acryviewer" (manufactured by Nippon Shokubai Co., Ltd.)
<Near-infrared absorbing dye>
<< Compound (A) >>
Compound (a-8): Compound (a-8) described in Table 1 above (absorption maximum wavelength in dichloromethane of 735 nm)
Compound (a-11): Compound (a-11) described in Table 1 above (absorption maximum wavelength in dichloromethane: 707 nm)
Compound (a-12): Compound (a-12) described in Table 1 above (maximum absorption wavelength 736 nm in dichloromethane)
≪Near-infrared absorbing dye (X) ≫
Compound (X-1): A squarylium compound represented by the following formula (X-1) (absorption maximum wavelength in dichloromethane: 670 nm)

Compound (X-2): A squarylium compound represented by the following formula (X-2) (maximum absorption wavelength in dichloromethane: 698 nm)

Compound (X-3): a cyanine compound represented by the following formula (X-3) (absorption maximum wavelength in dichloromethane: 681 nm)

Compound (X-4): Phthalocyanine compound represented by the following formula (X-4) (maximum absorption wavelength in dichloromethane: 698 nm)

Compound (X-5): phthalocyanine compound represented by the following formula (X-5) (absorption maximum wavelength in dichloromethane: 733 nm)

Compound (X-6): Cyanine compound represented by the following formula (X-6) (absorption maximum wavelength in dichloromethane: 760 nm)

Compound (X-7): Phthalocyanine compound represented by the following formula (X-7) (maximum absorption wavelength of 681 nm in dichloromethane)

<Solvent>
Solvent (1): Methylene chloride Solvent (2): N, N-dimethylacetamide Solvent (3): Ethyl acetate / toluene (weight ratio: 5/5)
Solvent (4): cyclohexane / xylene (weight ratio: 7/3)
Solvent (5): cyclohexane / methylene chloride (weight ratio: 99/1)
Solvent (6): N-methyl-2-pyrrolidone In Table 2, the film drying conditions of Examples and Comparative Examples are as follows. In addition, the coating film was peeled from the glass plate before drying under reduced pressure.

<Film drying conditions>
Condition (1): 20 ° C./8 hr → under reduced pressure 100 ° C./8 hr
Condition (2): 60 ° C./8 hr → 80 ° C./8 hr → under reduced pressure 140 ° C./8 hr
Condition (3): 60 ° C./8 hr → 80 ° C./8 hr → under reduced pressure 100 ° C./24 hr
Condition (4): 40 ° C./4 hr → 60 ° C./4 hr → under reduced pressure 100 ° C./8 hr

The optical filter of the present invention is a digital still camera, a mobile phone camera, a digital video camera, a personal computer camera, a surveillance camera, an automobile camera, a television, an in-vehicle device for a car navigation system, a portable information terminal, a video game machine, a mobile phone. It can be suitably used for game machines, fingerprint authentication system devices, digital music players, and the like. Furthermore, it can be suitably used as a heat ray cut filter or the like attached to glass or the like of automobiles and buildings.

1: Optical filter 2: Spectrophotometer 3: Light

Claims

An optical filter comprising: a transparent resin substrate containing a compound (A) represented by the following formula (I); and a near-infrared reflective film formed on at least one surface of the substrate.

[In the formula (I), M represents a substituted metal atom including two hydrogen atoms, two monovalent metal atoms, a divalent metal atom, or a trivalent or tetravalent metal atom, and there are a plurality of them. R a independently represents L 1, and a plurality of R b independently represents a hydrogen atom, a halogen atom, L 1 or —SO 2 —L 2 ,
L 1 is below L a, represents L b or L c, L 2 represents a following L a, L b, L c , L d or L e,
(L a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms (L b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms (L c ) an alicyclic hydrocarbon group having 3 to 14 carbon atoms (L d ) carbon An aromatic hydrocarbon group having 6 to 14 carbon atoms (L e ), a heterocyclic group having 3 to 14 carbon atoms, and the L a to Le are further an aliphatic hydrocarbon group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Halogen-substituted alkyl group, alicyclic hydrocarbon group having 3 to 14 carbon atoms, aromatic hydrocarbon group having 6 to 14 carbon atoms, heterocyclic group having 3 to 14 carbon atoms, and alkoxy group having 1 to 12 carbon atoms It may have at least one substituent L selected from the group consisting of ]
In the above formula (I), M is a divalent transition metal, trivalent or tetravalent metal halide, or tetravalent metal belonging to Groups 4 to 12 of the periodic table and belonging to Periods 4 to 5 Oxide,
R a is independently an alkyl group having 1 to 10 carbon atoms, a fluorine-substituted alkyl group having 1 to 6 carbon atoms, a cyclopentyl group or a cyclohexyl group,
R b is independently a hydrogen atom, a fluorine atom, an alkyl group having 1 to 10 carbon atoms, a cyclopentyl group, a cyclohexyl group or —SO 2 —L 2 ;
2. The optical filter according to claim 1, wherein L 2 is an alkyl group having 1 to 6 carbon atoms, an aromatic hydrocarbon group having 6 to 12 carbon atoms, or a heterocyclic group having 3 to 6 carbon atoms.
The transparent resin constituting the transparent resin substrate is a cyclic olefin resin, aromatic polyether resin, polyimide resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, polyamide resin, polyarylate resin , Polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin, allyl ester 3. The optical filter according to claim 1, wherein the optical filter is at least one resin selected from the group consisting of a series resin and a silsesquioxane resin.
The optical filter according to any one of claims 1 to 3, wherein the near-infrared reflective film is formed on both surfaces of the substrate.
The optical filter according to any one of claims 1 to 4, which is used for a solid-state imaging device.
A solid-state imaging device comprising the optical filter according to any one of claims 1 to 5.
A camera module comprising the optical filter according to any one of claims 1 to 5.
Compound (A) represented by the following formula (I), cyclic olefin resin, aromatic polyether resin, polyimide resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, polyamide resin, poly Allylate resin, polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin And a resin composition containing at least one resin selected from the group consisting of allyl ester resins and silsesquioxane resins.

[In the formula (I), M represents a substituted metal atom including two hydrogen atoms, two monovalent metal atoms, a divalent metal atom, or a trivalent or tetravalent metal atom, and there are a plurality of them. R a independently represents L 1, and a plurality of R b independently represents a hydrogen atom, a halogen atom, L 1 or —SO 2 —L 2 ,
L 1 is below L a, represents L b or L c, L 2 represents a following L a, L b, L c , L d or L e,
(L a ) an aliphatic hydrocarbon group having 1 to 12 carbon atoms (L b ) a halogen-substituted alkyl group having 1 to 12 carbon atoms (L c ) an alicyclic hydrocarbon group having 3 to 14 carbon atoms (L d ) carbon An aromatic hydrocarbon group having 6 to 14 carbon atoms (L e ), a heterocyclic group having 3 to 14 carbon atoms, and the L a to Le are further an aliphatic hydrocarbon group having 1 to 12 carbon atoms, and 1 to 12 carbon atoms. Halogen-substituted alkyl group, alicyclic hydrocarbon group having 3 to 14 carbon atoms, aromatic hydrocarbon group having 6 to 14 carbon atoms, heterocyclic group having 3 to 14 carbon atoms, and alkoxy group having 1 to 12 carbon atoms It may have at least one substituent L selected from the group consisting of ]