CA3014400C - Oxocarbon compound, resin composition, and ink composition - Google Patents

Abstract

An oxocarbon compound represented by the following formula (1) or (2):
(see formula 1) (see formula 2) wherein R1 to R4 each independently represent a structural unit represented by the following formula (3):
(see formula 3) wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these ring structures optionally having a substituent, R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring, * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2), and a total number of It electrons contained in the ring A and R7 is 12 or more.

Description

I I

TITLE OF INVENTION:
OXOCARBON COMPOUND, RESIN COMPOSITION, AND INK COMPOSITION
TECHNICAL FIELD
[0001]
The present invention relates to an oxocarbon compound having a squarylium skeleton or a croconium skeleton, and a resin composition and an ink composition containing the same.
BACKGROUND ART

[0002]
Oxocarbon compounds having a squarylium skeleton and a croconium skeleton are known as dyes having an absorption region in a visible to near-infrared range, and can be synthesized by using squaric acid or croconic acid as a raw material and introducing heterocyclic rings on both sides of the raw material. As such oxocarbon compounds, the following compounds are known, for example.

[0003]
Patent Literature 1 discloses the following squarylium compound (see Example 2 of Patent Literature 1).

[0004]
[Chemical Formula 1]
N
N H

[0005]
Patent Literature 2 discloses the following squarylium compound and croconium compound (see Examples 14 and 17 of Patent Literature 2).

[0006]
[Chemical Formula 2]

I I

\N 0-

[0007]
[Chemical Formula 3]

S [0008]
Patent Literature 3 discloses the following squarylium compound (see Example 1 of Patent Literature 3).
[0009]
[Chemical Formula 4]
0- Bu =

Bu -0 [0010]
Non-patent Literature 1 discloses the following squarylium compounds.
[0011]
[Chemical Formula 5]

HN \
D N H
------[0012]
Non-patent Literature 2 discloses the following croconium compounds.
[0013]

[Chemical Formula 6]

H H

R =
R

[0014]
Dyes having an absorption region in a near-infrared region have been studied for applying to various applications and are expected to be used as a security ink, a near-infrared cutoff filter and others.
[0015]
A security ink is used for printing encrypted information (e.g., barcode, two-dimensional code, OCR letters, and the like) in banknotes, cash vouchers, securities, lottery tickets or the like for the purpose of forgery prevention, or used for printing delivery information or the like on letters and baggage for system efficiency.
As means for reading the information printed by the security ink, light emitting elements such as various lasers and LEDs having emission wavelengths in the range of 850 nm to 1300 nm are usually used, and therefore, dyes used for the security ink are required to have a strong absorption in such a wavelength range and have excellent invisibility under visible light. For example, Patent Literatures 4 and 5 disclose an ink containing a phthalocyanine compound or a naphthalocyanine compound as a near-infrared absorbing dye, and Patent Literature 6 discloses a phthalocyanine compound having a maximum absorption wavelength at around 900 run.
[0016]
A near-infrared cutoff filter is installed, for example, in an image sensing device such as CCD (Charge Coupled Device) and CMOS (Complementary Metal-Oxide Semiconductor), whereby optical noise (e.g., ghost and flare) can be removed. For example, as such an optical filter, Patent Literature 3 discloses a near-infrared cutoff filter containing a squarylium compound having an absorption maximum wavelength in a wavelength range of 660 rim to 710 nm. In an ordinary image sensing device for visible light, an optical filter containing a dye having a I I

maximum absorption wavelength in a wavelength range of around 700 nm is installed, whereby incidence angle dependence of optical characteristics is reduced and viewing angle property can be improved.
[0017]
Meanwhile, some image sensing devices are required to be photographed under night vision as in a surveillance camera, in contrast to general digital cameras and video cameras. Photographing under night vision, as in nighttime, is performed in a state invisible by human eyes, so it is performed by irradiating near-infrared light and receiving the reflected light with an image sensing device, for example. Also in the image sensing device for night vision, it is required to reduce the incidence angle dependence of optical characteristics, similarly to an ordinary image sensing device for visible light; however in the image sensing device for night vision, it is difficult to reduce the incident angle dependence by using a near-infrared cutoff filter for visible light and it is needed to provide a cutoff filter which absorbs light of a wavelength region within the range of 800 nm to 1000 nm, for example. In this case as well, the filter is required to contain a dye having a strong absorption in such a wavelength region and having a high light transmittance in a visible light region, whereby well image photographing both under visible light and under night vision is realized.
CITATION LIST
PATENT LITERATURE
[0018]

Japanese Unexamined Patent Application Publication No. 2008-308602 Japanese Unexamined Patent Application Publication No. HO6-25165 Japanese Unexamined Patent Application Publication No. 2014-148567 Japanese Unexamined Patent Application Publication No. H07-164729 Japanese Unexamined Patent Application Publication No. 2002-309131 Japanese Unexamined Patent Application Publication No. 2007-56105 NON-PATENT LITERATURE
[0019]

Miltsov et al., "New Cyanine Dyes: Norindosquarocyanines", Tetrahedron Letters, 40 (1999): 4067-4068 Encinas et al., "Croconines: new acidochromic dyes for the near infrared region", Tetrahedron Letters, 43 (2002): 8391-8393 SUMMARY OF INVENTION
TECHNICAL PROBLEM
[0020]
As described above, a near-infrared absorbing dye has been studied for applying to a security ink, a near-infrared cutoff filter and the like, and in order to further expand its application, a dye capable of effectively absorbing light, for example, in a wavelength range exceeding 850 nm is required. However, oxocarbon compounds such as a squarylium compound and a croconium compound, being capable of absorbing light in such a long wavelength region, have not been known.
Meanwhile, as disclosed in Patent Literature 6, a phthalocyanine compound which is capable of absorbing light in a wavelength range around 900 nm is known, however, a phthalocyanine compound absorbs light in a visible light region and shows, for example, green color, and so there was room for improvement in terms of invisibility.
[0021]
The present invention has been achieved in view of the above circumstances, and an object of the present invention is to provide an oxocarbon compound which is capable of absorbing near-infrared light on a longer wavelength side and having high light transmittance in a visible light region, and a resin composition and an ink composition containing the same.

SOLUTION TO PROBLEM
[0022]
The oxocarbon compound of the present invention which solves the above problems is an oxocarbon compound represented by the following formula (1) or (2).
[0023]
[Chemical Formula 7]

(1) (2) In the formulas (1) and (2), R1 to R4 each independently represent a structural unit represented by the following formula (3).
[0024]
[Chemical Formula 8]

A \
NH
(3) In the formula (3), ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these ring structures optionally having a substituent; R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring; * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2); and a total number oft electrons contained in the ring A and R7 is 12 or more.
[0025]
The oxocarbon compound of the present invention is composed so that it electron system spreads from a squarylium skeleton or a croconium skeleton to a structural unit represented by the formula (3) and the total number of it electrons contained in the ring A and the substituent R7 in the structural unit of the formula (3) is 12 or more, and therefore, it can effectively absorb near-infrared light on a longer wavelength side, and for example, absorb light in the wavelength range exceeding 850 nm. Meanwhile, the oxocarbon compound itself has high light transmittance in a visible light region, so that it is excellent in invisibility under visible light.
[0026]
In the above formula (3), it is preferable that: R5 and R6 each independently represent hydrogen atom, an alkyl group optionally having a substituent, an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent or an aryloxycarbonyl group optionally having a substituent, or R5 and R6 are linked to each other to form a hydrocarbon ring optionally having a substituent ancUor a condensed ring structure, or a heterocyclic ring optionally having a substituent and/or a condensed ring structure; and R7 represents hydrogen atom, an alkyl group optionally having a substituent or an aryl group optionally having a substituent.
[0027]
The present invention also provides a resin composition comprising the oxocarbon compound of the present invention and a resin component. The resin composition may further comprise a liquid medium. The resin composition of the present invention can be suitably applied to an optical filter such as an image sensing device for night vision by forming a film, and can be also suitably applied to an image sensing device used under visible light since it has high transmittance in a visible light region. The resin composition of the present invention can be also suitably used for a welding resin by a laser welding method, and it can be used to be contained in a resin to be welded or used as an absorber of laser light, for example.
[0028]
The present invention also provides an ink composition comprising the oxocarbon compound of the present invention and a liquid medium. Since the ink oxocarbon compound of the present invention and a liquid medium. Since the ink composition of the present invention absorbs light in a near-infrared region and is excellent in invisibility under visible light, it can be suitably used as a security ink.
[0029]
The present invention further provides a condensed heterocyclic compound represented by the following formula (5) and a process for producing an oxocarbon compound comprising the step of reacting a condensed heterocyclic compound represented by the following formula (5) with squaric acid or croconic acid to obtain the oxocarbon compound represented by the above formula (1) or the above formula (2). The condensed heterocyclic compound represented by the following formula (5) can be suitably used as a raw material for producing the oxocarbon compound of the present invention.
[0030]
[Chemical Formula 9]

A \
(5) In the formula (5), ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these rings optionally having a substituent; 125 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring; and a total number of TC
electrons contained in the ring A and R7 is 12 or more.
[0030a]
In yet another aspect, the present invention provides an oxocarbon compound represented by the following formula (1) or (2):

(1) (2)

8 wherein R1 to R4 each independently represent a structural unit represented by the following formula (3):

*
A \ NH
(3) wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these ring structures optionally having a substituent, wherein the substituent is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group, cyano group, a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring, wherein the organic group is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an allcylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group and cyano group, and the polar functional group is selected from the group consisting of a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2), and a total number of it electrons contained in the ring A and R7 is 12 or more.
8a [0030b]
In yet another aspect, the present invention provides a condensed heterocyclic compound represented by the following formula (5):

A \
(5) wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these rings optionally having a substituent, R5 represents an alkyl group optionally having a substituent, an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent, or an aryloxycarbonyl group optionally having a substituent, R6 represents an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent, or an aryloxycarbonyl group optionally having a substituent, or R5 and R6 are linked to each other to form a hydrocarbon ring optionally having a substituent and/or a condensed ring structure or a heterocyclic ring optionally having a substituent and/or a condensed ring structure, R7 represents hydrogen atom, an organic group or a polar functional group, the substituent is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group, cyano group, a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, the organic group is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-8b containing group, carboxy group, a benzothiazole group, a halogenoalkyl group and cyano group, the polar functional group is selected from the group consisting of a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, and a total number of it electrons contained in the ring A and R7 is 12 or more.
[0030c]
In yet another aspect, the present invention provides a process for producing an oxocarbon compound comprising the step of reacting a condensed heterocyclic compound represented by the following formula (5):

A \
(5) wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these rings optionally having a substituent, wherein the substituent is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group, cyano group, a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, R5 to le each independently represent hydrogen atom, an organic group or a polar functional group, or IV and R6 are linked to each other to form a ring, wherein =
the organic group is selected from the group consisting of an alkyl group, an alkoxy = group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group and cyano group, and the polar functional group is selected from the group consisting of a halogeno 8c group, hydroxyl group, nitro group, an amino group and sulfo group, and a total number oft electrons contained in the ring A and R7 is 12 or more, with squaric acid or croconic acid to obtain an oxocarbon compound represented by the following formula (1) or the following formula (2):

(1) (2) wherein RI to R4 each independently represent a structural unit represented by the following formula (3):

*
A \ NH
(3) wherein ring A and R5 to R7 each have the same meaning as described above, * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2), and a total number of it electrons contained in the ring A and R7 is 12 or more.
ADVANTAGEOUS EFFECTS OF INVENTION
[0031]
The oxocarbon compound of the present invention and the resin composition and the ink composition containing the same can absorb near-infrared light on a longer wavelength side, and for example, absorb light in the wavelength range exceeding 850 8d nm, as well as they have high light transmittance in a visible light region, so that they are excellent in invisibility under visible light.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032]
Fig. 1 shows transmittance spectra of a croconium compound 1, a comparative croconium compound 1 and a comparative phthalocyanine compound 1 used in Examples.
DESCRIPTION OF EMBODIMENTS
[0033]
[1. Oxocarbon compound]
An oxocarbon compound of the present invention is represented by the following formula (1), which has a squarylium skeleton, or the following formula (2), which has a croconium skeleton.
[0034]
[Chemical Formula 101 (1) (2) [0035]
In the formulas (1) and (2), R' to R4 each independently represent a structural unit represented by the following formula (3).
[0036]
[Chemical Formula 11]

9 *
\
NH
(3) [0037]
In the formula (3), ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these ring structures optionally having a substituent; R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring; * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2); and a total number of it electrons contained in the ring A and R7 is 12 or more.
[0038]
In the formulas (1) and (2), RI and R2 may be the same or different from each other, and R3 and R4 may be the same or different from each other. When RI and are different from each other or R3 and R4 are different from each other, association or aggregation between molecules of the oxocarbon compound are suppressed, and improvement in solubility in solvents or resins is expected. Meanwhile, when RI and R2 are the same or when R3 and R4 are the same, improvement of durability against heat or light of the oxocarbon compound is expected.
[0039]
In some cases, there exists compounds having resonance relation to each other in compounds having a squarylium skeleton (hereinafter referred to as "squarylium compound") and compounds having a croconium skeleton (hereinafter referred to as "croconium compound"). Examples of compound having resonance relation to the squarylium compound of the formula (1) include, for example, compounds represented by the following formulas (la) and (lb). Examples of compound having resonance relation to the croconium compound of the formula (2) include, for example, compounds represented by the following formulas (2a) to (2c). The oxocarbon t compound of the present invention includes all these compounds having resonance relation; and specifically, the squarylium compound of the formula (1) includes compounds having resonance relation to that such as compounds represented by the following formulas (la) and (lb), and the croconium compound of the formula (2) includes compounds having resonance relation to that such as compounds represented by the following formulas (2a) to (2c).
[0040]
[Chemical Formula 12]
0 HN 0 g HN 0 0-+HN

R5 R6 / <I> R 6R5 R5 6 / = R7 R R5 R7 -õ,-N NH+ 0- NH 0- ci NH 0 A A
(1 a) (1) (lb) [0041]
[Chemical Formula 13]

R-g R5 R5 R6 R7 - R7 V a--NH +HN 0 NH

HN

(2a) (2) /
*---\
0 NH+ -NH -0 0 +HN

(2b) (2c) [0042]
In the structural unit represented by the formula (3) that is bonded to the squarylium skeleton or the croconium skeleton, * represents a bonding site to a 4-membered ring of the squarylium skeleton represented by the formula (1) or a 5-membered ring of the croconium skeleton represented by the formula (2).
[0043]
In the oxocarbon compound of the present invention, the total number of 7t electrons contained in the ring A and the substituent R7 is 12 or more. When the It electron system is formed in this manner, the oxocarbon compound can effectively absorb near-infrared light on a longer wavelength side, and for example, absorb light in the wavelength range exceeding 850 nm. Meanwhile, the oxocarbon compound shows high light transmittance in a visible light region, so that it is excellent in invisibility under visible light. In the case where the oxocarbon compound of the present invention absorbs light in a wavelength range exceeding 850 nm, the oxocarbon compound does not necessarily absorb light in the entire wavelength range exceeding 850 nm, and for example, it may absorb light in a part of the wavelength range of 850 nm to 1300 nm in a certain degree.
[0044]
In the formula (3), the ring A represents an aromatic hydrocarbon ring, an aromatic heterocyclic ring or a condensed ring containing these ring structures, and these rings may have a substituent. When the oxocarbon compound has the ring A, the It electron system spreads over a wide range from the squarylium skeleton or the croconium skeleton to the ring A via a pyrrole ring, whereby lengthening of the absorption wavelength can be realized.
[0045]
The aromatic hydrocarbon ring of the ring A is not particularly limited as long as it consists of carbon atom and hydrogen atom and has aromaticity; and examples thereof include, for example, a benzene ring, a naphthalene ring, a phenanthrene ring, an anthracene ring, a tetracene ring, a fluoranthene ring, a benzofluoranthene ring, a cyclotetradecaheptaene ring, and others. The aromatic hydrocarbon ring may have only one ring structure or condensed two or more ring structures. The aromatic heterocyclic ring of the ring A is not particularly limited as long as it has a ring structure containing at least one atom selected from N (nitrogen atom), 0 (oxygen atom) and S
(sulfur atom) and has aromaticity; and examples thereof include, for example, a furan ring, a thiophene ring, a pyrrole ring, a pyrazole ring, an oxazole ring, a thiazole ring, an imidazole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a purine ring, a pteridine ring, and others. The aromatic heterocyclic ring may have only one ring structure or condensed two or more ring structures. The condensed ring containing these ring structures has a structure in which an aromatic hydrocarbon ring and an aromatic heterocyclic ring are condensed, and examples thereof include, for example, an indole ring, an isoindole ring, a benzimidazole ring, a quinoline ring, a benzopyran ring, an acridine ring, a xanthene ring, a carbazole ring, and others. These ring structures may be condensed with the pyrrole ring in the formula (3) at any position.
[0046]
The number of It electrons contained in the ring A, that is, the number of it .. electrons contained in the aromatic hydrocarbon ring, the aromatic heterocyclic ring or the condensed ring containing these ring structures is not particularly limited, and may be, for example, 4 or more or 6 or more. From the viewpoint of spreading the it electron system to a wider range in distance in the oxocarbon compound and facilitating lengthening the wavelength of the absorbing region, the number of it electrons contained in the ring A is preferably 10 or more, more preferably 14 or more, and even more preferably 16 or more. Meanwhile, the upper limit of the number of it electrons contained in the ring A is not particularly limited; however, in consideration of easily production of the oxocarbon compound and solvent solubility thereof, the number of it electrons contained in the ring A is preferably 26 or less, more preferably 24 or less, and even more preferably 22 or less. The number of It electrons contained in the ring A is a number including IC electrons of a carbon-carbon bond shared by the ring A and the pyrrole ring.
[0047]
As the substituent which the ring A may have (hereinafter referred to as "substituent X"), organic groups or polar functional groups are shown.
Examples of the organic group of the substituent X include, for example, an alkyl group, an alkoxy group, an alkylthiooxy group (an alkylthio group), an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthiooxy group (an arylthio group), an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group (carboxylic acid group), a benzothiazole group, a halogenoalkyl group, cyano group, and others.

Examples of the polar functional group of the substituent X include a halogeno group, hydroxyl group, nitro group, an amino group, sulfo group (sulfonic acid group), and others.
[0048]
Examples of the alkyl group include a linear or branched alkyl group such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl and icosyl; alicyclic alkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl and cyclodecyl;
and others.
The number of carbon atoms in the alkyl group is preferably 1 to 20, more preferably 1 to 10, even more preferably 1 to 6, and in the case of an alicyclic alkyl group, it is particularly preferably 3 or more. The alkyl group may have a substituent, and examples of the substituent, which the alkyl group may have, include a halogen group, hydroxyl group, carboxy group, an alkoxy group, cyano group, nitro group, an amino group, sulfo group, and others.
[0049]
Examples of the alkoxy group include, for example, methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, undecyloxy, dodecyloxy, tridecyloxy, tetradecyloxy, pentadecyloxy, hexadecyloxy, heptadecyloxy, octadecyloxy, nonadecyloxy, icosyloxy, and others. The number of carbon atoms in the alkoxy group is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5. The alkyl group in the alkoxy group may be linear or branched.
[0050]
Examples of the alkylthiooxy group (alkylthio group) include, for example, methylthiooxy (methylthio), ethylthiooxy (ethylthio), propylthiooxy (propylthio), butylthiooxy (butylthio), pentylthio (pentylthio), hexylthiooxy (hexylthio), heptylthiooxy (heptylthio), octylthiooxy (octylthio), nonylthiooxy (nonylthio), decylthiooxy (decylthio), undecylthiooxy (undecylthio), dodecylthiooxy (dodecylthio), tridecylthiooxy (tridecylthio), tetradecylthiooxy (tetradecylthio), pentadecylthiooxy (pentadecylthio), hexadecylthiooxy (hexadecylthio), heptadecylthiooxy (heptadecylthio), octadecylthiooxy (octadecylthio), nonadecylthiooxy (nonadecylthio), icosylthiooxy (icosylthio), and others. The number of carbon atoms in the alkylthiooxy group is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5.
The alkyl group in the alkylthiooxy group may be linear or branched.
[0051]
Examples of the alkoxycarbonyl group include, for example, an unsubstituted alkoxycarbonyl group such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, butoxycarbonyl, pentyloxycarbonyl, hexyloxycarbonyl, heptyloxycarbonyl, octyloxycarbonyl, decyloxycarbonyl and octadecyloxycarbonyl, and a substituted alkoxycarbonyl group such as trifluoromethyloxycarbonyl.
Examples of the substituent include a halogeno group and others. The number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 20, more preferably 2 to 10, and even more preferably 2 to 5. The alkyl group in the alkoxycarbonyl group may be linear or branched.
[0052]
Examples of the alkylsulfonyl group include, from example, a substituted or unsubstituted alkylsulfonyl group such as methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, butylsulfonyl, hexylsulfonyl, cyclohexylsulfonyl, 2-ethylhexylsulfonyl, octylsulfonyl, methoxymethylsulfonyl, cyanomethylsulfonyl and trifluoromethylsulfonyl. The number of carbon atoms in the alkylsulfonyl group is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5.
The alkyl group in the alkylsulfonyl group may be linear, branched or cyclic.
[0053]
Examples of the aryl group include, for example, phenyl, biphenyl, naphthyl, anthryl, phenanthryl, pyrenyl, indenyl, azulenyl, fluorenyl, terphenyl, quarterphenyl, pentalenyl, heptalenyl, biphenylenyl, indacenyl, acenaphthylenyl, phenalenyl group, and others. The number of carbon atoms in the aryl group is preferably 6 to 25, and more preferably 6 to 15. The aryl group may have a substituent, and examples of the substituent, which the aryl group may have, include an alkyl group, an alkoxy group, a halogen group, a halogenoalkyl group, cyano group, nitro group, thiocyanate group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, carbamoyl group, sulfo group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, sulfamoyl group, and others.
[0054]
Examples of the aralkyl group include, for example, benzyl, phenethyl, phenylpropyl, phenylbutyl, phenylpentyl, and others. The aralkyl group may have a substituent, and examples of the substituent, which the aralkyl group may have, include an alkyl group, an alkoxy group, a halogeno group, a halogenoalkyl group, cyano group, nitro group, thiocyanate group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, carbamoyl group, sulfo group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, sulfamoyl group, and others. The number of carbon atoms in the aralkyl group is preferably 7 to 25, and more preferably 7 to 15.
[0055]
Examples of the aryloxy group include, for example, phenyloxy, biphenyloxy, naphthyloxy, anthryloxy, phenanthryloxy, pyrenyloxy, indenyloxy, azulenyloxy, fluorenyloxy, terphenyloxy, quaterphenyloxy, pentalenyloxy, heptalenyloxy, biphenylenyloxy, indacenyloxy, acenaphthylenyloxy, phenalenyloxy, and others.
The number of carbon atoms in the aryloxy group is preferably 6 to 25, and more preferably 6 to 15.
[0056]
Examples of the arylthioxy group (arylthio group) include, for example, phenylthioxy, biphenylthioxy, naphthylthioxy, anthrylthiooxy, phenanthrylthiooxy, pyrenylthiooxy, indenylthiooxy, azulenylthioxy, fluorenylthioxy, terphenylthioxy, quarterphenylthioxy, pentalenylthiooxy, heptalenylthiooxy, biphenylenylthioxy, indacenylthioxy, acenaphthylenylthiooxy, phenalenylthioxy, and others. The number of carbon atoms in the arylthioxy group is preferably 6 to 25, and more preferably 6 to 15.

=
[0057]
Examples of the aryloxycarbonyl group include, for example, a substituted or unsubstituted phenyloxycarbonyl group such as phenoxycarbonyl, 4-dimethylaminophenyloxycarbonyl, 4-diethylaminophenyloxycarbonyl, 2-chlorophenyloxycarbonyl, 2-methylphenyloxycarbonyl, 2-methoxyphenyloxycarbonyl, 2-butoxyphen yloxycarbonyl, 3-chlorophenyloxycarbonyl, 3-trifluoromethylphenyloxycarbonyl, 3-cyanophenyloxycarbonyl, 3-nitrophenyloxycarbonyl, 4-fluorophenyloxycarbonyl, 4-cyanophenyloxycarbonyl and 4-methoxyphenyloxycarbonyl; a substituted or unsubstituted naphthyloxycarbonyl group such as 1-naphthyloxycarbonyl and 2-naphthyloxycarbonyl; and others. The number of carbon atoms in the aryloxycarbonyl group is preferably 7 to 25, and more preferably 7 to 15.
[0058]
Examples of the arylsulfonyl group include, for example, a substituted or unsubstituted phenylsulfonyl group such as phenylsulfonyl, 1-naphthylsulfonyl, 2-naphthylsulfonyl, 2-chlorophenylsulfonyl, 2-methylphenylsulfonyl, 2-methoxyphenylsulfonyl, 2-butoxyphenylsulfonyl, 2-fluorophenylsulfonyl, 3-methylphenylsulfonyl, 3-chlorophenylsulfonyl, 3-trifluoromethylphenylsulfonyl, 3-cyanophenylsulfonyl, 3-nitrophenylsulfonyl, 3 -fluorophenylsulfonyl, 4-methylphenylsulfonyl, 4-fluorophenylsulfonyl, 4-cyanophenylsulfonyl, 4-methoxyphenylsulfonyl and 4-dimethylaminophenylsulfonyl; a substituted or unsubstituted naphthylsulfonyl group such as 1-naphthylsulfonyl and 2-naphthylsulfonyl; and others. The number of carbon atoms in the arylsulfonyl group is preferably 6 to 25, and more preferably 6 to 15.
[0059]
Examples of the arylsulfinyl group include, for example, a substituted or unsubstituted phenylsulfinyl group such as phenylsulfinyl, 2-chlorophenylsulfinyl, 2-methylphenylsulfinyl, 2-methoxyphenylsulfinyl, 2-butoxyphenylsulfinyl, 2-fluorophenylsulfinyl, 3-methylphenylsulfinyl, 3-chlorophenylsulfinyl, 3-trifluoromethylphenylsulfinyl, 3-cyanophenylsulfinyl, 3-nitrophenylsulfinyl, 4-methylphenylsulfinyl, 4-fluorophenylsulfinyl, 4-cyanophenylsulfinyl, 4-methoxyphenylsulfinyl and 4-dimethylaminophenylsulfinyl; a substituted or unsubstituted naphthylsulfinyl group such as 1-naphthylsulfinyl and 2-naphthylsulfinyl;
and others. The number of carbon atoms in the arylsulfinyl group is preferably 6 to 25, and more preferably 6 to 15.
[0060]
Examples of the heteroaryl group include, for example, thienyl, thiopyranyl, isothiocromenyl, pyrrolyl, imidazolyl, pyrazolyl, pyridyl, pyralidinyl, pyrimidinyl, pyridazinyl, thiazolyl, isothiazolyl, furanyl, pyranyl, and others. The number of carbon atoms in the heteroaryl group is preferably 2 to 20, and more preferably 3 to 15.
[0061]
Examples of the amide group include those represented by the formula:
-NHCORal, wherein Rai represents an alkyl group, an aryl group, an aralkyl group or a heteroaryl group. Specific examples of the alkyl group, the aryl group, the aralkyl group and the heteroaryl group are shown as groups mentioned above, and a part of hydrogen atoms may be replaced by a halogen atom.
[0062]
Examples of the sulfonamide group include those represented by the formula:
-NHS021e, wherein le2 represents an alkyl group, an aryl group, an aralkyl group or a heteroaryl group. Specific examples of the alkyl group, the aryl group, the aralkyl group and the heteroaryl group are shown as groups mentioned above, and a part of hydrogen atoms may be replaced by a halogen atom.
[0063]
Examples of the ethylene-containing group include those represented by the formula: -CRa3=CRa4-Ra5, wherein Ra3 to Ra5 represent hydrogen atom, an aliphatic hydrocarbon group, an aryl group, a heteroaryl group (particularly pyridyl group), cyano group, an alkoxycarbonyl group, carboxy group, and others, and these groups may have a substituent. The aliphatic hydrocarbon groups of Ra3 to le5 may be saturated or unsaturated, and are preferably unsaturated. As such aliphatic hydrocarbon group, a group having a repeating unit represented by -(CH=CH)k- (k is an integer of 1 to 10, preferably an integer of 1 to 5) is preferable, and a vinyl group is exemplified. In addition, 1,1-dicyanoethylene group and 1-cyanoethylene group are also preferable.
As the aliphatic hydrocarbon group, for example, those having 1 to 20 carbon atoms are preferable, and those having 1 to 10 carbon atoms are more preferable.
Examples of the aryl group, heteroaryl group and alkoxycarbonyl group of Ra3 to Ras include the above-mentioned aryl group, heteroaryl group and alkoxycarbonyl group.
[0064]
Examples of the imine-containing group include those represented by the formula: -CH=N-le6, wherein le6 represents an amino group optionally having a substituent. The amino group of Rao may be substituted or unsubstituted.
Examples of the amino group having a substituent include a monoalkylamino group, a dialkylamino group, a monoarylamino group, a diarylamino group, a monoalkylmonoarylamino group, and others. Examples of the alkyl group or aryl group bonded to the amino group of Ra6 include the above-mentioned alkyl group and aryl group.
[0065]
Examples of the halogenoalkyl group include, for example, a monohalogenoalkyl group such as fluoromethyl, 3-fluoropropyl, 3-chloropropyl, 6-fluorohexyl and 4-fluorocyclohexyl; a dihalogenoalkyl group such as dichloromethyl;
an alkyl group having a trihalometyl unit such as 1,1-dihydro-perfluoroethyl, 1,1-dihydro-perfluoro-n-propyl, 1,1-dihydro-perfluoro-n-butyl, 2,2-bis(trifluoromethyl)propyl and 2,2,2-trichloroethyl; a perhalogenoalkyl group such as trifluoromethyl, perfluoroethyl, perfluoro-n-pentyl and perfluoro-n-hexyl;
and others.
The number of carbon atoms in the halogenoalkyl group is preferably 1 to 20, more preferably 1 to 10, and even more preferably 1 to 5. The halogen of the halogenoalkyl group is preferably a fluorine atom, a chlorine atom or a bromine atom, and particularly preferably a fluorine atom.
[0066]
Examples of the halogeno group include fluoro group, chloro group, bromo group, and iodo group.

[0067]
As the substituent X, among the above, an alkyl group, an alkoxy group, an alkylthiooxy group, an alkoxycarbonyl group, an aryl group, an aryloxycarbonyl group, cyano group, a halogeno group and nitro group are preferable, and an alkyl group, an alkoxy group, an alkylthiooxy group, a halogeno group and an aryl group are more preferable, whereby increasing solvent solubility of the oxocarbon compound and finely adjusting the maximum absorption wavelength of the oxocarbon compound to a desired wavelength range are facilitated. In addition, the effect of easily production of the oxocarbon compound is also obtained. In this case, the number of carbon atoms in the alkyl group, the alkoxy group and the alkylthiooxy group is preferably 1 to 5, more preferably 1 to 3, even more preferably 1 to 2, the number of carbon atoms in the alkoxycarbonyl group is preferably 2 to 6, more preferably 2 to 4, even more preferably 2 to 3, and the number of carbon atoms in the aryl group and the aryloxycarbonyl group is preferably 6 to 12, more preferably 6 to 10. The ring A may not have the substituent X. In the case where the ring A has the substituent X, the number thereof is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1 to 2. In the case where the ring A has the plurality of substituents X, the plurality of substituents X
may be the same or different from each other.
[0068]
In the formula (3), R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring. Examples of the organic group and the polar functional group of R5 to include the groups exemplified as the organic group and the polar functional group of the substituent X. Examples of the ring structure formed from R5 and R6 include a hydrocarbon ring and a heterocyclic ring, and these ring structures may have aromaticity or may not have aromaticity.
[0069]
In the case where R5 and R6 are not linked to each other and are independent groups, it is preferable that R5 and R6 each independently represent hydrogen atom, an alkyl group optionally having a substituent, an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent, or an aryloxycarbonyl group optionally having a substituent. Specific examples of these groups are shown as groups exemplified as the substituent X. When R5 and R6 are such groups, increasing solvent solubility of the oxocarbon compound and finely adjusting the maximum absorption wavelength of the oxocarbon compound to a desired wavelength range are facilitated. In addition, the effect of easily production of the oxocarbon compound is also obtained.
[0070]
In the case where R5 or R6 is an alkyl group or an alkoxycarbonyl group, the number of carbon atoms (the number of carbon atoms excluding the substituent) of the alkyl group contained in these groups is preferably 1 to 20, more preferably 1 to 12, even more preferably 1 to 10 in a linear or branched alkyl group, and preferably 4 to 7, more preferably 5 to 6 in an alicyclic alkyl group. Preferable examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, t-butyl, pentyl, hexyl, heptyl, octyl, cyclopentyl, cyclohexyl, and others. Note that, in the case where R5 or R6 is an alkyl group, the substituent which the alkyl group may have does not include an aryl group. In the case where R5 or R6 is an aryl group or an aryloxycarbonyl group, the number of carbon atoms (the number of carbon atoms excluding the substituent) of the aryl group contained in these groups is preferably 6 to 10. Preferable examples of the aryl group include phenyl, naphthyl, and others. In the case where R5 or R6 is an aralkyl group, the number of carbon atoms (the number of carbon atoms excluding the substituent) is preferably 7 to 20, more preferably 7 to 15. Examples of the aralkyl group include benzyl, phenethyl, phenylpropyl, and others. Preferable examples of the substituent which each of R5 and R6 may have include an alkoxy group, a halogeno group, halogenoalkyl group, cyano group, a nitro group, and others.
[0071]
In the case where R5 and R6 are linked to each other to form a ring, the structural unit of the above formula (3) is represented by the following formula (4).
The ring structure formed by R5 and R6, that is, the ring B in the following formula (4) may be any ring structure, and the ring B may have a substituent. The ring B
is a preferably a hydrocarbon ring optionally having a substituent and/or a condensed ring structure, or a heterocyclic ring optionally having a substituent and/or a condensed ring structure.
[0072]
[Chemical Formula 14]

A
(4) [0073]
Examples of the hydrocarbon ring of the ring B include, for example, a monocyclic cycloalkane having 3 to 10 carbon atoms such as cyclopentane, cyclohexane and cycloheptane; a monocyclic cycloalkene having 3 to 10 carbon atoms such as cyclopentene, cyclopentadiene, cyclohexene, cyclohexadiene (for example, 1,3-cyclohexadiene), cycloheptene and cycloheptadiene; and others. As the heterocyclic ring of the ring B, a ring structure of the above-mentioned hydrocarbon ring in which one or more of carbon atoms constituting the ring of the hydrocarbon ring is replaced by at least one atom selected from N (nitrogen atom), S (sulfur atom) and 0 (oxygen atom); and examples thereof include, for example, a furan ring, a tetrahydrofuran ring, a thiophene ring, a tetrahydrothiophene ring, a pyrrole ring, a pyrrolidine ring, a pyrazole ring, an oxazole ring, a thiazole ring, an imidazole ring, a pyridine ring, a piperidine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a pyran ring, a tetrahydropyran ring, and others. These hydrocarbon ring and heterocyclic ring may have a condensed ring structure condensed with another ring, and examples of such ring structure include, for example, an indene ring, a naphthalene ring, an anthracene ring, a fluorene ring, a benzofluorene ring, an indole ring, an isoindole ring, a benzimidazole ring, a quinoline ring, a benzopyran ring, an acridine ring, a xanthene ring, a carbazole ring, a purine ring, a pteridine ring, and others.
[0074]

The hydrocarbon ring and the heterocyclic ring of the ring B may have a substituent, and examples of such substituent include an alkyl group, an alkoxy group, an aryl group, a thioalkoxy group, an aryloxy group, a thioaryloxy group, an alkylamido group, a halogeno group, a halogenoalkyl group, cyano group, nitro group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, and others. The halogenoalkyl group may be one in which at least a part of hydrogen atoms of the alkyl group is substituted with a halogen atom, and is preferably a perhalogenoalkyl group in which all of hydrogen atoms of the alkyl group are substituted with halogen atoms. As the halogenoalkyl group, a fluoroalkyl group is more preferable, and a perfluoroalkyl group is even more preferable. The number of carbon atoms in the halogenoalkyl group is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1 to 2.
[0075]
From the viewpoint of lengthening the absorption wavelength of the oxocarbon compound, the ring B preferably contains it electrons, and examples of such ring structure include, for example, a cyclohexadiene ring, a pyrrole ring, a pyran ring, an indene ring, an indole ring, an isoindole ring, a benzopyran ring, a fluorene ring, a xanthene ring, and ohters. As the structural unit represented by the above formula (4) in this case, structural units represented by the following formulas (4-1) to (4-12) are shown, for example.
[0076]
[Chemical Formula 15]

i 1 , R8,/, \ R9 k R8 ,R8 V
I \ \ 'N I I )\ N I. /
R7 R7 R7 ' R7 a NH * 0 NH * = NH * 0 N H *
(4-1) (4-2) (4-3) (4-4) - \
R8-C. - NI\ N I R7 i N R7 N R8 fr A i l \--- i N
' R7 a NH * = NH * = NH *
0 N H *
(4-5) (4-6) (4-7) (4-8) v R8 0, R8 0., R8 R9 0 --/, 11 8 11 9 ,\/
R9--/L,_ \ N 1 ----FR \-R7 R7 "'-, R7 ---- R7 = NH *
0 NH * CIV NH * A \ - *
¨ NH
(4-9) (4-10) (4-11) (4-12) [0077]
In the formulas (4-1) to (4-12), R8 and R9 represent a group or an atom bonded to the ring structure formed by R5 and R6, and it is preferable that R8 and R9 each independently represent a group or an atom selected from the group consisting of hydrogen atom, an alkyl group, an alkoxy group, a halogeno group, a halogenoalkyl group, cyano group, nitro group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group and an arylsulfonyl group. Details of the preferred embodiment and others of the halogenoalkyl group are as described above. The number of each of R8 and R9 bonded to the ring varies depending on the ring structure, and in the case where plural R8 or plural R9 are bonded, plural R8 or plural R9 may be the same or different from each other. Among them, it is preferable that R8 and R9 are each independently a group or an atom selected from the group consisting of hydrogen atom, an alkyl group, an alkoxy group, a halogeno group, a halogenoalkyl group and cyano group, and more preferably a group or an atom I I

=
selected from the group consisting of hydrogen atom, a halogen group, a halogenoalkyl group and cyano group. In this case, it is preferable that all of R8 and R9, which are bonded to the ring structure formed by R5 and R6, are not hydrogen atoms.
That is, a substituent selected from the group consisting of an alkyl group, an alkoxy gruop, a halogen group, a halogenoalkyl group and cyano group is preferably bonded to the ring structure formed by R5 and R6, and more preferably, a substituent selected from the group consisting of a halogeno group, a halogenoalkyl group and cyano group is bonded to the ring structure formed by R5 and R6. Thereby, lengthening the absorption wavelength of the oxocarbon compound can be realized.
[0078]
It is preferable that the ring B is a hydrocarbon ring having a condensed ring structure which may have a substituent, or a heterocyclic ring having a condensed ring structure which may have a substituent, whereby further lengthening the absorption wavelength of the oxocarbon compound can be realized. The hydrocarbon ring or the heterocyclic ring having a condensed ring structure is preferably formed so that TE
electron conjugated system spreads to the condensed ring, and from such a viewpoint, the number of it electrons contained in the ring B is preferably 6 or more, more preferably 8 or more, even more preferably 10 or more, and still even more preferably 12 or more. The upper limit of the number of it electrons contained in the ring B is not particularly limited; however, considering ease of production and solvent solubility of the oxocarbon compound, it is preferably 20 or less, more preferably 18 or less, and even more preferably 16 or less. The number of IC electrons contained in the ring B
means a number of TE electrons contained in the ring structure of the ring B, and in the case where the ring B has a condensed ring structure, it includes it electrons contained in the condensed ring structure, and it does not include TE electrons contained in a substituent which the ring B may have.
[0079]
Preferable examples of the ring B include an indene ring, an indole ring, an isoindole ring, a benzopyran ring, a fluorene ring and a xanthene ring. In the structural units represented by the above formulas (4-1) to (4-12), the structural units represented by the formulas (4-2), (4-3), (4-4), (4-6), (4-8), (4-9), (4-11) and (4-12) are preferable.
From the viewpoint of lengthening the absorption wavelength, a fluorene ring optionally having a substituent or a xanthene ring optionally having a substituent are particularly preferable as the ring B, and in the structural units represented by the above formulas (4-1) to (4-12), the structural units represented by formulas (4-4) and (4-12) are particularly preferable. In these structural units, it is preferable that all of R8 bonded to the benzene ring contained in the fluorene ring or the xanthene ring are not hydrogen atoms and all of R9 are not hydrogen atoms, and at least one of the above-mentioned substituent (particularly, a halogeno group, a halogenoalkyl group or cyano group) is bonded to each of the benzene ring.
[0080]
It is preferable that R7 is hydrogen atom, an alkyl group optionally having a substituent or an aryl group optionally having a substituent, and details of the alkyl group optionally having a substituent and the aryl group optionally having a substituent are made reference to the explanation on Rs and R6 of the above. When R7 is an aryl group optionally having a substituent, the it electron system of the oxocarbon compound expands and the absorption wavelength can be shifted to a longer wavelength, that are preferable. In this case, the number of it electrons contained in R7 is preferably 6 to 10 from the viewpoint of ease of production of the oxocarbon compound.
Specifically, as the aryl group of R7, phenyl or naphthyl whcih may have a substituent is preferable, and phenyl is more preferable. Despite of that, R7 may not have a it electron and may be hydrogen atom or an alkyl group (particularly an alkyl group having 1 to 4 carbon atoms). In this case, it is preferable in that solvent solubility of the oxocarbon compound can be easily enhanced and production of the oxocarbon compound is facilitated. That the number of It electrons contained in R7 means a number of it electrons contained in R7 of the it electron system continuously spreading from the squarylium skeleton or the croconium skeleton to R7.
[0081]
In the oxocarbon compound, the total number of it electrons contained in the rings A and R7 is 12 or more, preferably 14 or more, and more preferably 16 or more, I

=
whereby near-infrared light on a longer wavelength side (for example, light in a wavelength range exceeding 850 nm) can effectively absorb. In the oxocarbon compound of the present invention, it is more preferable that the number of it electrons contained in the ring A is in such a range, whereby the it electron system spreads over a wider range in distance and lengthening the absorption wavelength is easily achieved.
Examples of the ring A in this case include a phenanthrene ring, an anthracene ring, a tetracene ring, a fluoranthene ring, a benzofluoranthene ring, a cyclotetradecaheptaene ring, an acridine ring, a carbazole ring, and others. Meanwhile, the upper limit of the total number of it electrons contained in the rings A and R7 is not particularly limited;
however, in consideration of ease of production and solvent solubility of the oxocarbon compound, it is preferably 30 or less, more preferably 28 or less, and even more preferably 26 or less.
[0082]
Among the structural units represented by the above formula (4), examples of the structural units which are relatively easy to produce and which can give oxocarbon compounds capable of absorbing light on a longer wavelength side are shown below.
The structural units shown in the following formulas (4-21) to (4-26) are specific examples of the structural unit of the above formula (4-4), and the structural units shown in the following formulas (4-27) to (4-32) are specific examples of the structural unit of the above formula (4-12). In the following formulas (4-21) to (4-32), the explanations on R7 to R9 in the following formulas (4-21) to (4-32) are made reference to the above description. A fluoranthene ring is provided as the ring A in the formulas (4-21), (4-22), (4-27) and (4-28), a phenanthrene ring is provided as the ring A in the formulas (4-23), (4-24), (4-29) and (4-30), and an anthracene ring is provided as the ring A in the formulas (4-25), (4-26), (4-31) and (4-32). The binding (condensed ring) form of these ring structures to the pyrrole ring is not limited to embodiments shown in the following formulas. Further, as the ring A, other ring structures may be provided.
[0083]
[Chemical Formula 16]

J

=

R8 -+ R8 + R9 -1-*
NH * NH * NH
(4-21) (4-22) (4-23) R8 + R8 R9 R8 --I--V

NH * *
NH
(4-24) (4-25) NH *
(4-26) [0084]
[Chemical Formula 17]

R8 0 ---/., RB 0 v, NH * NH *
NH *
(4-27) (4-28) (4-29) X LJ-\

-, R7 *
NH * * NH
NH
(4-30) (4-31) (4-32) [0085]

As the oxocarbon compound having the structural unit represented by the above formula (4), a croconium compound represented by the formula (2) is preferable from the viewpoint of absorbing light on a longer wavelength side. Further, in the formula (2), the rings A in R3 and R4 preferably have the same ring structure, and the rings B in R3 and R4 preferably have the same ring structure. More preferably, in the formula (2), the rings A in R3 and R4 have the same structure, wherein the structure including a ring structure of the ring A and a structure of a substituent which may bond thereto, and the rings B of R3 and R4 have the same structure, wherein the structure including a ring structure of the ring B and a structure of a substituent which may bond thereto.
[0086]
In the oxocarbon compound of the present invention, the maximum absorption wavelength is preferably 835 rim or longer, more preferably 840 rim or longer, even more preferably 845 nm or longer, from the viewpoint of increasing an absorption rate .. of light in the wavelength range exceeding 850 nm. The upper limit of the maximum absorption wavelength is not particularly limited, and may be, for example, 1300 nm or shorter, or 1100 rim or shorter.
[0087]
As to visible light transmittance, an average transmittance in a wavelength range of 400 nm to 700 nm is preferably 83% or more, more preferably 84% or more, and even more preferably 85% or more when the transmittance at the maximum absorption wavelength is set to 10% (or 10% or less).
[0088]
As described above, the oxocarbon compound of the present invention is capable of absorbing near-infrared light on the longer wavelength side, specifically effectively absorbing light in the wavelength range exceeding, for example, 850 nm, since the it electron system spreads from the squarylium skeleton or the croconium skeleton to the ring A (or further to the substituent R7) and the total number of it electrons contained in the ring A and the substituent R7 is 12 or more.
Meanwhile, since the oxocarbon compound itself has high light transmittance in a visible light region, it is excellent in invisibility under visible light. For example, some phthalocyanine compounds have the absorption maximum wavelength in a wavelength range exceeding 850 tun, but the phthalocyanine compounds have an absorption peak derived from the soret band in a wavelength range around 400 nm and may cause to show green color; meanwhile, the oxocarbon compound of the present invention is excellent in invisibility while functioning as a near-infrared absorbing dye.
[0089]
The oxocarbon compound of the present invention can be produced by reacting a condensed heterocyclic compound represented by the following formula (5) with squaric acid or croconic acid. In the following formula (5), ring A and R5 to R7 each represent the same meaning as that in the above formula (3), and the total number of 7( electrons contained in the ring A and R7 is 12 or more. Preferred embodiments of the ring A and R5 to R7 are also as described above.
[0090]
[Chemical Formula 18]

A \ NJ/
(5) [0091]
The condensed heterocyclic compound represented by the formula (5) is suitably used as a raw material of the oxocarbon compound of the present invention, whereby the oxocarbon compound of the present invention can be easily produced.
That is, the oxocarbon compound of the present invention can be produced by a process comprising the step of reacting the condensed heterocyclic compound represented by the formula (5) with squaric acid or croconic acid to obtain the oxocarbon compound represented by the formula (1) or (2). Specifically, the squarylium compound represented by the formula (1) can be produced by reacting the condensed heterocyclic compound of the formula (5) with squaric acid, and the croconium compound .1 represented by the formula (2) can be produced by reacting the condensed heterocyclic compound of the formula (5) with croconic acid.
[0092]
The amount of the condensed heterocyclic compound used in reacting the condensed heterocyclic compound with squaric acid or croconic acid is preferably equal molar or more, more preferably 1.5 times molar or more, even more preferably 2 times molar or more, and preferably 5 times molar or less, more preferably 4 times molar or less, even more preferably 3 times molar or less, relative to squaric acid or croconic acid.
[0093]
The reaction of the condensed heterocyclic compound with squaric acid or croconic acid is preferably carried out in the presence of a solvent. Examples of usable solvents include, for example, chlorinated hydrocarbons such as chloroform and methylene chloride; aromatic hydrocarbons such as benzene, toluene, xylene and trimethylbenzene; chlorinated aromatic compounds such as chlorotoluene and dichlorobenzene; ethers such as tetrahydrofuran (THF), dioxane, cyclopentyl methyl ether, diisopropyl ether and diethyl ether; alcohols such as methanol, ethanol, propanol, isopropanol, butanol, tert-butanol and tert-amyl alcohol; and others. These solvents may be used alone, or two or more of them may be used in combination. When an alcohol is used as the reaction solvent, it is preferable to use a tertiary alcohol. The amount (total amount) of the solvent used is preferably equal mass or more, more preferably 5 times mass or more, even more preferably 10 times mass or more, and preferably 100 times mass or less, relative to squaric acid or croconic acid.
[0094]
In the reaction of the condensed heterocyclic compound with squaric acid or croconic acid, the reaction temperature may be appropriately set, and for example, is preferably 30 C or higher, more preferably 60 C or higher, even more preferably 80 C
or higher, and preferably 170 C or lower, more preferably 140 C or lower. The reaction is preferably carried out under reflux condition. The reaction time is not particularly limited and may be appropriately set depending on the progress of the reaction, and for example, it is preferably 0.5 hour or longer, more preferably 1 hour or longer, and preferably 48 hours or shorter, more preferably 24 hours or shorter. The atmosphere during the reaction is preferably an inert gas (e.g., nitrogen, argon, and the like) atmosphere.
[0095]
The squarylium compound can be synthesized by appropriately employing a known synthesis method of reacting the condensed heterocyclic compound with squaric acid. For example, the squarylium compound can be synthesized by the synthesis process described in the following article: Serguei Miltsov et at., "New Cyanine Dyes:
Norindosquarocyanines", Tetrahedron Letters, Vol.40, Issue 21, p.4067-4068 (1999).
[0096]
A process for synthesizing the croconium compound is not particularly restricted, and it can be synthesized by appropriately adopting a known synthesis method of reacting the condensed heterocyclic compound with croconic acid. For example, the croconium compound can be synthesized by the methods described in Japanese Unexamined Patent Application Publication Nos. 2002-286931, 2007-31644, 2007-31645, and 2007-169315.
[0097]
The condensed heterocyclic compound of the formula (5) can be synthesized by appropriately employing a known synthesis method, and produced, for example, according to the following reaction formula. In the following reaction formulas, ring A
and R5 to R7 each represent the same meaning as in the above formula (3).
[0098]
[Chemical Formula 19]

A \ R5 C H2R7 N HN H2 = HCI + R7 --a-- A \ N

(6) (7) (5) [0099]

i =
For example, the condensed heterocyclic compound in which the ring A is a fluoranthene ring, R5 and R6 are methyl groups and R7 is hydrogen atom can be synthesized by reacting fluoranthenylhydrazine hydrochloride with 3-methyl-2-butanone. Thus, the condensed heterocyclic compound of the formula (5) can be synthesized by reacting hydrazine hydrochloride having an aromatic hydrocarbon ring structure, an aromatic heterocyclic ring structure or a condensed ring structure containing these rings (that is, the compound of the above formula (6)) with a dimethylketone derivative (that is, the compound of the above formula (7)).
Synthesis of the condensed heterocyclic compounds can be also referred to the following article:
Sajjadifar et al., "New 3H-Indole Synthesis by Fischer's Method. Part I", Molecules, Vol.15, p.2491-2498 (2010).
[0100]
The oxocarbon compound obtained by reacting the condensed heterocyclic compound of the formula (5) with squaric acid or croconic acid can be appropriately purified by known purification means such as filtration, silica gel column chromatography, alumina column chromatography, sublimation, recrystallization, and crystallization. The chemical structure of the obtained oxocarbon compound can be analyzed by known analytical methods such as mass spectrometry, single crystal X-ray structural analysis, fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy.
[0101]
[2. Resin composition]
The oxocarbon compound of the present invention may be mixed with a resin component to give a resin composition. The resin composition contains at least the oxocarbon compound of the present invention and a resin component. Since the resin composition of the present invention can effectively absorb light in a near-infrared region, for example, light in a wavelength range exceeding 850 nm, it can be suitably applied to an optical filter such as an image sensing device for night vision by forming a resin molding such as a film. In thus formed optical filter, incident angle dependence of optical characteristics on the short wavelength side of a near-infrared region is = =
g reduced, the viewing angle is improved, and further transmittance in a visible light region is high, and therefore, thus formed optical filter can be suitably applied to an image sensing device used also under visible light. The resin molding can be also applied to a near-infrared absorbing film or a near-infrared absorbing plate that shields a heat ray for energy saving, a material for a solar cell utilizing visible light and near-infrared light, a specific wavelength absorption filter for a plasma display panel (PDP) or CCD, and the like.
[0102]
The resin composition of the present invention can be also suitably used for laser welding applications. Joining a resin by a laser welding method can be performed by placing a light transmitting resin that transmits laser light on a light absorbing resin that absorbs laser light and irradiating laser light from the light transmitting resin side. The irradiated laser light passes through the light transmitting resin and energy is absorbed at the surface of the light absorbing resin to generate heat, whereby the light absorbing resin melts, the light transmitting resin also melts due to thermal conduction, and the both resins are joined. In some cases, as the light absorbing resin, a colored resin containing carbon black, a black dye or the like is used;
however, since laser light having a wavelength of 800 nm to 1300 nm (for example, semiconductor laser, YAG laser, fiber laser) is used in the laser welding, forming the light absorbing resin from the resin composition of the present invention enables laser welding between transparent resins. Thus, the oxocarbon compound of the present invention can function as an absorber for laser light, that is, as a heat generation source.
In the laser welding method, the resin composition of the present invention also can be used as a laser light absorber disposed between two light transmitting resins.
[0103]
The oxocarbon compound contained in the resin composition may be a squarylium compound, a croconium compound, or both. The oxocarbon compound contained in the resin composition may be only one kind or may be two kinds or more.
[0104]
Two or more kinds of the squarylium compounds represented by the above formula (1) may be contained in the resin composition, or two or more kinds of the croconium compounds represented by the above formula (2) may be contained in the resin composition. The thus formed resin composition can effectively absorb the light in a near-infrared region, improves solubility of the oxocarbon compound in the resin, and facilitates forming the resin composition containing the oxocarbon compound at a high concentration. In this case, from the viewpoint of increasing the solubility of the oxocarbon compound in the resin, the resin composition preferably contains at least squarylium compounds having a structure in which RI and R2 are different from each other in the above formula (1) or preferably contains at least croconium compounds having a structure in which R3 and R4 are different from each other in the above formula (2). More preferably, the resin composition contains three or more kinds of the oxocarbon compounds, and examples of such resin composition include, for example, a resin composition containing a squarylium compound in which RI and R2 are both Rx in the above formula (1), a squarylium compound in which RI and R2 are both Ry in the above formula (1) and a squarylium compound in which RI is Rx and R2 is Ry in the above formula (1), and a resin composition containing a croconium compound in which R3 and R4 are both Rx in the above formula (2), a croconium compound in which R3 and R4 are both Ry in the above formula (2) and a croconium compound which is R3 is Rx and R4 is Ry in the above formula (2). Such resin composition is preferable since it contains plural oxocarbon compounds and is easy to produce. Here, the above-described Rx and Ry represent any structural unit represented by the above formula (3), and Rx and Ry are not the same.
[0105]
The oxocarbon compound of the present invention can be regarded as one kind of dye, and the resin composition of the present invention may contain other dyes together with the oxocarbon compound of the present invention as long as the desired performance according to an application is secured. Examples of the dye which may be contained in the resin composition include, for example, squarylium dyes or croconium dyes other than the oxocarbon compound of the present invention, cyclic tetrapyrrole dyes which may have copper (e.g., Cu(II)), zinc (e.g., Zn(II)) or the like as a central metal (e.g., porphyrins, chlorins, phthalocyanines and cholines), cyanine dyes, quaterrylene dyes, naphthalocyanine dyes, nickel complex dyes, copper ion dyes, diimmonium dyes, subphthalocyanine dyes, xanthene dyes, azo dyes, dipyrromethene dyes, and others. These other dyes may be used alone or two or more of them may be used in combination.
[0106]
In the case where the resin composition of the present invention also contains other dyes, the content of other dyes is preferably 60 mass% or less, more preferably 40 mass% or less, even more preferably 20 mass% or less, relative to 100 mass% of the total of the oxocarbon compound of the present invention and other dyes; and it is particularly preferable that any other dye is not substantially contained.
[0107]
From the viewpoint of developing desired performance, the content of the oxocarbon compound of the present invention in the resin composition is preferably 0.01 mass% or more, more preferably 0.3 mass% or more, and even more preferably 1 mass% or more, based on 100 mass% of the solid content of the resin composition. In addition, from the viewpoint of enhancing formability or film-forming property of the resin composition, the content of the oxocarbon compound of the present invention in the resin composition is preferably 25 mass% or less, more preferably 20 mass%
or less, and even more preferably 15 mass% or less, based on 100 mass% of the solid content of the resin composition. In the case where the resin composition also contains other dyes, the total content of the oxocarbon compound of the present invention and other dyes is preferably within the above-mentioned range. The mass of the solid content of the resin composition means mass obtained by removing a liquid medium from the resin composition.
[0108]
As the resin component contained in the resin composition, a known resin can be used. As the resin component, those having high transparency and capable of dissolving or dispersing the oxocarbon compound of the present invention are preferable. In the case where other dyes are used in combination, the resin component which is capable of dissolving or dispersing also other dyes is preferable. By employing such resin component, it becoms possible to achieve both high transmittance in a wavelength range to be transmitted and high absorption in a wavelength range to be blocked.
[0109]
As the resin component, not only a resin which has been completely polymerized but also a resin raw material (including a precursor of the resin, a raw material of the precursor, a monomer constituting the resin, and the like) which is to be polymerized or crosslinked to be incorporated into the resin at the time of molding the resin composition can be used. In the present invention, both are the resin component.
However, in the latter case, a part or all of the structure of the oxocarbon compound may be decomposed due to unreacted substances, reactive terminal functional groups, ionic groups, catalysts, acid/basic groups, and others present in the reaction solution obtained by the polymerization reaction. Therefore, in the case that there is such a concern, it is desirable to form the resin composition by blending the oxocarbon compound in a resin which has been completely polymerized.
[0110]
Examples of the resin component include, for example, a (meth)acrylic resin, a (meth)acrylic urethane resin, a polyvinyl chloride resin, a polyvinylidene chloride resin, a polyolefin resin (e.g., polyethylene resin, polypropylene resin, and the like), a cycloolefin resin (including cycloolefin copolymer, norbornene resin, and the like), a petroleum resin, a rosin resin, a rosin ester resin, an urea resin, a melamine resin, an urethane resin, a styrene resin, a styrene-acryl resin, a styrene-maleic acid resin, polyvinyl acetate, an ethylene-vinyl acetate resin, a vinyl acetal resin, a polyamide resin (e.g., nylon and the like), an aramid resin, a polyimide resin, a polyamide-imide resin, an alkyd resin, a phenol resin, an epoxy resin, a polyester resin (e.g., polybutylene terephthalate resin, polyethylene terephthalate resin, polyarylate resin, and the like), a polysulfone resin, a butyral resin, a polycarbonate resin, a polyether resin, an acrylonitrile butadiene styrene resin, an acrylonitrile-styrene copolymer, a cellulose derivative (e.g., ethyl cellulose, cellulose acetate, nitrocellulose, and the like), a silicone =
=
resin, a modified silicone resin (e.g., (meth)acrylic silicone resin, alkyl polysiloxane resin, silicone urethane resin, silicone polyester resin, silicone acrylic resin, and the like), a fluorine resin (e.g., fluorinated aromatic polymer, polytetrafluoroethylene, perfluoroalkoxy fluorine resin, fluorinated polyaryl ether ketone, fluorinated polyimide, fluorinated polyamic acid, fluorinated polyether nitrile, and the like), a diallyl phthalate resin, a coumarone-indene resin, a terpene phenol resin, a xylene resin, an alkyd resin, a maleic acid resin, a fumaric acid resin, and others [0111]
The resin component preferably has high transparency, that makes it easy to suitably apply the resin composition to optical applications and laser welding applications. For example, a total light transmittance of the resin component at a thickness of 0.1 mm is preferably 75% or higher, more preferably 80% or higher, and even more preferably 85% or higher. The upper limit of the total light transmittance of the resin component is not particularly limited, and the total light transmittance may be 100% or lower, or 95% or lower, for example. The total light transmittance is determined according to JIS K 7105.
[0112]
It is preferable that the resin component has a high glass transition temperature (Tg), whereby heat resistance of the resin composition and various molded products obtained therefrom can be enhanced. The glass transition temperature of the resin component is preferably, for example, 50 C or higher, more preferably 70 C or higher, and even more preferably 80 C or higher. The upper limit of the glass transition temperature of the resin component is not particularly limited, and from the viewpoint of securing molding processability of the resin composition, it is preferably, for example, .. 380 C or lower.
[0113]
The resin composition may be a thermoplastic resin composition that can be used for molding such as injection molding and extrusion molding, or may be a paintable resin composition that can be applied by a spin coating method, a solvent casting method, a roll coating method, a spray coating method, a bar coating method, a dipping coating method, a screen printing method, a flexographic printing method, an inkjet method, or the like.
[0114]
In the case where the resin composition is a thermoplastic resin composition, a molded product can be obtained from the resin composition by injection molding, extrusion molding, vacuum molding, compression molding, blow molding or the like.
In this method, a thermoplastic resin is used as the resin component, and the oxocarbon compound and the thermoplastic resin are blended and heat-molded, thereby obtaining a molded product. For example, the oxocarbon compound may be added to a powder or pellet of a base resin, heated to about 150 C to 350 C to be melted, and then molded.
The shape of the molded product is not particularly limited, and examples thereof include a plate, a sheet, a granule, a powder, a block, a particle agglomerate, a sphere, an ellipsoid, a cube, a column, a rod, a cone, a cylinder, a spicular, a fibrous, a hollow filamentous, a porous, and others. The molded product may have any deformed shape.
In kneading the resin, additives such as an ultraviolet absorber and a plasticizer, that are used for ordinary resin molding, may be added.
[0115]
In the case where the resin composition is a paintable resin composition, a liquid or paste-like resin composition containing the oxocarbon compound is coated on a transparent substrate (for example, a resin plate, a film, a glass plate or the like), whereby a film having a thickness of 200 pm or less or a planar molded product such as a plate having a thickness of more than 200 p.m can be formed. The paintable resin composition comprises the oxocarbon compound, a resin component and a liquid medium, and can be obtained, for example, by dissolving the oxocarbon compound in a solvent containing a resin component, or dispersing the oxocarbon compound in a dispersion medium containing a resin component.
[0116]
In the case where the resin composition is a paintable resin composition, a solvent-soluble resin that is soluble in an organic solvent is preferably used as the resin component. The solvent-soluble resin means a resin soluble in an organic solvent, and a resin which is soluble in 1 part by mass or more based on 100 parts by mass of an organic solvent is preferable. When the resin component is a solvent-soluble resin, a thin film having a smaller thickness can be easily produced by forming a film using, for example, a spin coating method, a solvent casting method, or the like. The solvent-soluble resin may have a reactive group capable of undergoing a crosslinking reaction (curing reaction), wherein the reactive group may be, for example, a ring-opening polymerizable group such as an epoxy group, an oxetane ring and an ethylene sulfide group, or a radically curable group and/or an addition curable group such as an acrylic group, a methacryl group and a vinyl group. Examples of the solvent-soluble resin include, for example, a polyimide resin, a polyamide-imide resin, a fluorinated aromatic polymer, a (meth)acrylic resin, a polyamide resin, an aramid resin, a polysulfone resin, a cycloolefin resin, an urethane resin, a phenolic resin, an epoxy resin, a polyarylate resin, a polycarbonate resins, and others.
[0117]
As the resin, a polyimide resin, a polyamide-imide resin, a fluorinated aromatic polymer, a (meth)acrylic resin, a polysulfone resin, a cycloolefin resin, an epoxy resin, a polyarylate resin, and a polycarbonate resin are preferable from the viewpoint of excellent transparency and heat resistance.
[0118]
The polyimide resin is a polymer having an imide bond in the repeating unit of the main chain, and can be obtained, for example, by polymerizing a tetracarboxylic acid dianhydride and a diamine to obtain a polyamic acid, and dehydrating and cyclizing (namely, imidizing) it. As the polyimide resin, an aromatic polyimide in which aromatic rings are linked by an imide bond is preferably used. As the polyimide resin, for example, Kapton (registered trademark) available from Du Pont, Aurum (registered trademark) available from Mitsui Chemicals, Meldin (registered trademark) available from Saint-Gobain, TPS (registered trademark) T13 000 series available from Toray Plastics Precision Co., Ltd., and others can be used.
[0119]
The polyamide-imide resin is a polymer having an amide bond and an imide bond in the repeating unit of the main chain. As the polyamide-imide resin, for example, TorIon (registered trademark) available from Solvay Advanced Polymers, Vylomax (registered trademark) available from Toyobo Co., Ltd., TPS
(registered trademark) TI5000 series available from Toray Plastic Precision Co., Ltd., and others can be used.
[0120]
The fluorinated aromatic polymer is polymer having a repeating unit containing an aromatic ring having one or more fluorine atoms and at least one bond selected from the group consisting of an ether bond, a ketone bond, a sulfone bond, an amide bond, an imide bond and an ester bond. Among them, a polymer essentially having a repeating unit containing an aromatic ring having one or more fluorine atoms and an ether bond. As the fluorinated aromatic polymer, for example, those described in Japanese Unexamined Patent Application Publication No. 2008-181121 can be used.
[0121]
The (meth)acrylic resin is a polymer having a repeating unit derived from (meth)acrylic acid or a derivative thereof, and for example, a resin having a repeating unit derived from a (meth)acrylic acid ester such as a poly(meth)acrylic ester resin is preferably used. The (meth)acrylic resin also preferably has a ring structure in the main chain, and examples of the ring structure include, for example, carbonyl group-containing ring structures such as a lactone ring structure, a glutaric anhydride structure, a glutarimide structure, a maleic anhydride structure and a maleimide ring structure; and carbonyl group-free ring structures such as an oxetane ring structure, an azetidine ring structure, a tetrahydrofuran ring structure, a pyrrolidine ring structure, a tetrahydropyran ring structure and a piperidine ring structure. The carbonyl group-containing ring structure may also include a structure containing a carbonyl derivative group such as an imide group. As the (meth)acrylic resin having a carbonyl group-containing ring structure, those disclosed in, for example, Japanese Unexamined Patent Application Publication Nos. 2004-168882, 2008-179677, WO 2005/54311, Japanese Unexamined Patent Application Publication No. 2007-31537, and others can be used.

[0122]
The polysulfone resin is a polymer having a repeating unit containing an aromatic ring, a sulfonyl group (-SO2-), and an oxygen atom. As the polysulfone resin, for example, Sumika Excel (registered trademark) PES3600P or PES4100P
available from Sumitomo Chemical Co., Ltd., UDEL (registered trademark) P-1700 available from Solvay Specialty Polymers Co., Ltd., or the like can be used.
[0123]
The cycloolefin resin is a polymer obtained by polymerizing a cycloolefin as at least a part of the monomer component and is not particularly limited as long as it has an alicyclic structure in a part of the main chain. As the cycloolefin resin, for example, Topas (registered trademark) available from Polyplastics Co., Ltd., Apel (registered trademark) available from Mitsui Chemicals, Zeonex (registered trademark) and Zeonor (registered trademark) available from Zeon Corporation, Arton (registered trademark) available from JSR Corporation, and others can be used.
[0124]
The epoxy resin is a resin that can be cured by crosslinking epoxy compounds (prepolymer) in the presence of a curing agent or a curing catalyst. Examples of the epoxy compound include aromatic epoxy compounds, aliphatic epoxy compounds, alicyclic epoxy compounds, hydrogenated epoxy compounds, and others. As the epoxy resin, for example, fluorene epoxy (Ogsol (registered trademark) PG-100) available from Osaka Gas Chemicals Co., Ltd., a bisphenol A epoxy compound (JER
(registered trademark) 828EL) and a hydrogenated bisphenol A epoxy compound (JER
(registered trademark) YX8000) available from Mitsubishi Chemical Corporation, an alicyclic liquid epoxy compound (Celloxide (registered trademark) 2021P) available from Daicel Corporation, and others can be used.
[0125]
The polyarylate resin is a polymer obtained by polycondensation of a dihydric phenol compound and a dibasic acid (for example, an aromatic dicarboxylic acid such as phthalic acid), and has a repeating unit containing an aromatic ring and an ester bond in the main chain. As the polyarylate resin, for example, Vectran (registered =
trademark) available from Kuraray Co., Ltd., U polymer (registered trademark) and Unifiner (registered trademark) available from Unitika Ltd., and others can be used.
[0126]
The polycarbonate resin is a polymer containing a carbonate group (-0-(C=0)-0-) in the repeating unit of the main chain. As the polycarbonate resin, for example, Panlite (registered trademark) available from Teijin, Iupilon (registered trademark), Novarex (registered trademark) and Xantar (registered trademark) available from Mitsubishi Engineering-Plastics Corporation, SD polyca (registered trademark) available from Sumika Styron Polycarbonate, and others can be used.
[0127]
The resin composition may contain a liquid medium such as an organic solvent;
and for example, in the case where the resin composition is a paintable resin composition, the resin composition can be easily coated since it contains a liquid medium. The liquid medium may function as a solvent of the oxocarbon compound or may function as a dispersion medium. Examples of the liquid medium include, for example, ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; glycol derivetives (an ether compound, an ester compound, an ether ester compound, and the like) such as PGMEA (2-acetoxy-1 -methoxypropane), ethylene glycol monobutyl ether, ethylene glycol monoethyl ether and ethylene glycol ethyl ether acetate; amides such as N,N-dimethylacetamide; esters such as ethyl acetate, propyl acetate and butyl acetate; pyrrolidones such as N-methyl-pyrrolidone (concretely, 1-methy1-2-pyrrolidone and the like); aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as cyclohexane and heptane; ethers such as tetrahydrofuran, dioxane, diethyl ether and dibutyl ether; and others. These liquid media may be used alone, or two or more of them may be used in combination.
[0128]
The content of the liquid medium is preferably 50 mass% or more, more preferably 70 mass% or more, and preferably less than 100 mass%, more preferably 95 mass% or less, based on 100 mass% of the resin composition. By adjusting the content of the liquid medium within such a range, it becomes easy to obtain the resin =
composition having a high concentration of the oxocarbon compound.
[0129]
Incidentally, amides such as N,N-dimethylacetamide may decompose the oxocarbon compound, so that the use amount thereof is preferably small.
Therefore, the content of amides is preferably 60 mass% or less, more preferably 40 mass%
or less, even more preferably 20 mass% or less, still even more preferably 5 mass% or less, and particularly preferably 0 mass% (that is, amides are not contained).
[0130]
The resin composition may contain, for example, a compound having an absorption ability in a wavelength range of 350 nm to 400 nm (that is, ultraviolet absorber). The existance of these compounds suppresses deterioration of the resin composition due to the light in the wavelength range of 350 nm to 400 nm. In the case where a compound having an absorption ability in the wavelength range of 350 nm to 400 nm is used in combination, TINUVIN (registered trademark) series available from BASF Co., Ltd., Zislizer (registered trademark) series available from Sankyo Kasei Co., Ltd., Adk Stab (registered trademark) series available from Adeka Corporation, Sumisorb (registered trademark) series available from Sumitomo Chemical Co., Ltd., Biosorb (registered trademark) series available from Kyodo Chemical Co., Ltd., Seesorb (registered trademark) series available from Shipro Kasei Kaisha, and others can be used as the compound having an absorption ability in the wavelength range of 350 nm to 400 nm.
[0131]
The resin composition may contain a surface conditioner, which suppresses appearance defects such as striation and dents in a resin layer when the resin composition is cured to form the resin layer. The kinds of the surface conditioner are not particularly limited, and a siloxane surfactant, an acetylene glycol surfactant, a fluorine surfactant, an acrylic leveling agent, or the like can be used. As the surface conditioner, for example, BYK (registered trademark) series available from BYK

Chemie and KF series available from Shin-Etsu Chemical Co., Ltd., and others can be used.

[0132]
The resin composition may contain a dispersant, which stabilizes dispersibility of the oxocarbon compound in the resin composition, thereby suppressing reaggregation.
The kinds of the dispersant is not particularly limited, and EFKA series available from Efka Additives, BYK (registered trademark) series available from BYK Chemie, Solspers (registered trademark) series available from Lubrizol Japan, Disparon (registered trademark) series available from Kusumoto Chemicals, Ajisper (registered trademark) series available from Ajinomoto Fine-Techno Co., Ltd., KP series available from Shin-Etsu Chemical Co., Ltd., Polyflow series available from Kyoeisha Chemical Co., Ltd., Megafac (registered trademark) series available from DIC
Corportaion, Disper Aid series available from San Nopco Limited, and others can be used.
[0133]
The resin composition of the present invention may contain various additives such as a plasticizer, a surfactant, a viscosity modifier, an antifoaming agent, an antiseptic agent, a specific resistance adjusting agent, and an adhesion improver, as needed.
[0134]
[3. Optical filter (Application example of resin composition)]
The resin composition of the present invention can be preferably used as a resin composition for preparing filter used in various applications such as optical device applications, display device applications, mechanical parts, electric/electronic parts, and others. As a filter for optical applications, it can be suitably applied to an optical filter of an image sensing device for particularly night vision, whereby an optical filter suitable for an image sensing device for night vision, of which the incident angle dependence of optical characteristics in a near-infrared region is reduced and the viewing angle is improved, can be obtained. The filter may be formed from a single resin layer or a plurality of resin layers, or may be integrated with a support.
[0135]
The filter integrated with a support can be formed, for example, by coating the resin composition on a surface of the support (or in the case of having another layer such as a binder layer between the support and the resin layer, the surface of the another layer) using a spin coating method or a solvent casting method, and drying or curing.
Or, the filter may be formed by thermocompression bonding a planar molded product formed from the resin composition to the support.
[0136]
The resin layer formed from the resin composition may be provided on only one side of the support or may be provided on both sides thereof. The thickness of the resin layer is not particularly limited, and is preferably, for example, 0.5 gm or more, more preferably 1 gm or more, and preferably 10 mm or less, more preferably 5 mm or .. less, even more preferably 3 mm or less, particularly preferably 1 mm or less, from the viewpoint of securing desired near-infrared light cutoff performance.
[0137]
As the support, it is preferable to use a transparent substrate such as a resin plate, a resin film, a glass plate or the like. As the resin plate or the resin film used for the support, for example, one formed from the above-described resin component is preferably used. When a glass plate is used as the support, it is preferable to provide a binder layer formed from, for example, a silane coupling agent between the support and the resin layer. Thereby, adhesion between the resin layer and the glass support can be enhanced. A silane coupling agent may be contained in the resin composition forming the resin layer as an adhesion improver, and also in this case, adhesion between the resin layer and the glass support can be enhanced.
[0138]
On the resin layer formed from the resin composition, a protective layer composed of the same or different resin as the resin layer, as a second resin layer, may be laminated. By providing the protective layer, durability (resistance to decomposition) of the oxocarbon compound contained in the resin layer can be enhanced. The protective layer may be provided on only one side of the resin layer or may be provided on both sides thereof. In the case where the resin layer is provided on the support, the protective layer is preferably provided on the surface of the resin layer opposite to the support.

[0139]
From the viewpoint of suppressing decomposition of the oxocarbon compound contained in the resin layer, the protective layer is preferably formed to have a low oxygen permeability, for example, have an oxygen permeability of 100 cc/m2/day or lower, more preferably 70 cc/m2/day or lower, and even more preferably 50 cc/m2/day or lower, at 23 C under dry condition, measured according to JIS K 7126-2 method.
The lower limit of the oxygen permeability is not particularly limited, and may be 0 cc/m2/day. The oxygen permeability is measured by introducing oxygen gas into a chamber on one side of the test piece and introducing nitrogen gas into a chamber on the other side thereof. From the viewpoint of suppressing decomposition of the oxocarbon compound, the resin layer and/or the protective layer may contain an ultraviolet absorber.
[0140]
In the case of forming an optical filter from the resin composition of the present invention, the optical filter may comprise a layer having antireflection property or anti-glare property for reducing glare of fluorescent lamp or the like (antireflection film), a layer having scratch prevention property, a transparent substrate having other functions, or the like.
[0141]
The optical filter may comprise a near-infrared reflection film (for example, a reflection film in the wavelength range of 700 nm to 800 nm) on the resin layer. The near-infrared reflection film is preferably provided on a light incident side of the resin layer. As the near-infrared reflection film, an aluminum vapor deposition film, a noble metal thin film, a resin film which contains indium oxide as a main component and in which metal oxide fine particles containing a small amount of tin oxide are dispersed, a dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately laminated, or the like can be employed.
Providing the near-infrared reflection film in the optical filter makes it possible to cut near-infrared light from transmitted light of the optical filter. The near-infrared reflection film may also have an ultraviolet ray reflective function.

[0142]
The near-infrared reflection film and the antireflection film (visible light antireflection film) can be composed of a dielectric multilayer film in which high refractive index material layers and low refractive index material layers are alternately laminated. As a 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 in the range of 1.7 to 2.5 is usually selected. Examples of the material constituting the high refractive index material layer include, for example, oxides such as titanium oxide, zinc oxide, zirconium oxide, lanthanum oxide, yttrium oxide, indium oxide, niobium oxide, tantalum oxide, tin oxide, and bismuth oxide; nitrides such as silicon nitride; mixtures of the above oxides and nitrides, and the above oxides or nitrides with which a metal such as aluminum and copper or carbon is doped (e.g., tin-doped indium oxide (ITO), antimony-doped tin oxide (ATO)), and others. As a 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 in the range of 1.2 to 1.6 is usually selected. Examples of the material constituting the low refractive index material layer include, for example, silicon dioxide (silica), alumina, lanthanum fluoride, magnesium fluoride, sodium aluminum hexafluoride, and others.
[0143]
The optical filter can be used as one of the constituents of the image sensing device. The image sensing device is also called a solid-state image sensing device or an image sensor chip, and is an electronic component which converts light of a subject into an electrical signal or the like and outputs it. The image sensing device usually comprises a detection element (sensor) such as CCD (Charge Coupled Device) or CMOS (Complementary Metal-Oxide Semiconductor) and may comprise a lens. The image sensing device can be used for a mobile phone camera, a digital camera, an in-vehicle camera, a surveillance camera, a display element (e.g., LEDs and the like), and the like. In particular, the image sensing device including the optical filter formed from the resin composition of the present invention can be suitably applied to a surveillance camera for night vision or the like. The image sensing device comprises one or more of the above-described optical filters, and may further comprise another filter (for example, a visible light cutoff filter, an infrared cutoff filter, an ultraviolet cutoff filter, or the like), as needed.
[0144]
The resin composition of the present invention can be used for applying to any base material, in addition to the filter for optical use described above. The base material is not particular limited, as long as a resin layer can be formed by applying the resin composition, and examples thereof include, for example, steels, nonferrous metals (light metals, noble metals, rare metals, rare earths, copper, zinc, lead, tin, and the like), wood, glass, concrete, stone, ceramics, resin, rubber, leather, paper, cloth, hair, skin and others. The shape of the base material is also not particularly limited, and examples thereof include a granular, a powder, a block, an aggregate of them, a plate, a sheet, a sphere, an ellipsoid, a cubic, a column, a rod, a cone, a cylinder, a spicular, a fibrous, a hollow filamentous, a porous, and others.
[0145]
[4. Ink composition]
The oxocarbon compound of the present invention can be applied to an ink composition. The ink composition contains at least the oxocarbon compound of the present invention and a liquid medium. The ink composition of the present invention can effectively absorb light in a wavelength range exceeding, for example, 850 nm, have high visible light transmittance, and be excellent in invisibility, so it can be suitably used as a security ink.
[0146]
The oxocarbon compound contained in the ink composition may be a squarylium compound, a croconium compound, or both. The oxocarbon compound contained in the ink composition may be only one kind or may be two kinds or more.
[0147]
Two or more kinds of the squarylium compounds represented by the above formula (1) may be contained in the ink composition, or two or more kinds of the croconium compounds represented by the above formula (2) may be contained in the ink composition. The thus formed ink composition can effectively absorb the light in a near-infrared region, improves solubility of the oxocarbon compound in the liquid medium, and facilitates forming the ink composition containing the oxocarbon compound at a high concentration. In this case, from the viewpoint of increasing the solubility of the oxocarbon compound in the liquid medium, the ink composition preferably contains at least squarylium compounds having a structure in which RI and R2 are different from each other in the above formula (1) or preferably contains at least croconium compounds having a structure in which R3 and R4 are different from each other in the above formula (2). More preferably, the ink composition contains three or more kinds of the oxocarbon compounds, and examples of such a ink composition include, for example, a ink composition containing a squarylium compound in which RI
and R2 are both Rx in the above formula (1), a squarylium compound in which RI
and R2 are both Ry in the above formula (1) and a squarylium compound in which RI
is R., and R2 is Ry in the above formula (1), and a ink composition containing a croconium compound in which R3 and R4 are both Rõ in the above formula (2), a croconium compound in which R3 and R4 are both Ry in the above formula (2) and a croconium compound which is R3 is Rõ and R4 is Ry in the above formula (2). Such ink composition is preferable since it contains plural oxocarbon compounds and is easy to produce. Here, the above-described Rx and Ry represent any structural unit represented by the above formula (3), and Rx and Ry are not the same.
[0148]
The ink composition may contain other dyes together with the oxocarbon compound of the present invention, as long as the desired performance according to an application is secured. Details of other dyes is made reference to the descriptions of other dyes which may be included in the resin composition. In the application of a security ink or the like, the content of other dyes is preferably 50 mass% or less, more preferably 20 mass% or less, and even more preferably 5 mass% or less, relative to 100 mass% of the total of the oxocarbon compound of the present invention and the other dyes.

[0149]
The content of the oxocarbon compound of the present invention in the ink composition is preferably 0.1 mass% or more, more preferably 1 mass% or more, and preferably 40 mass% or less, more preferably 30 mass% or less, even more preferably 20 mass% or less, based on 100 mass% of the ink composition. In the case where the ink composition also contains other dyes, the total content of the oxocarbon compound of the present invention and other dyes is preferably within the above-mentioned range.
Adjusting to such a range makes it easier to obtain a printed surface of sufficient density and to ensure stability of the oxocarbon compound and other dyes in the ink composition.
[0150]
The liquid medium may function as a solvent of the oxocarbon compound or may function as a dispersion medium. Examples of the liquid medium include, for example, ketones such as acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, diisobutyl ketone and cyclohexanone; alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, tert-amyl alcohol and n-hexanol; glycol derivetives (an ether compound, an ester compound, an ether ester compound, and the like) such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl glycol, propylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate (PGMEA); esters such as ethyl acetate, propyl acetate, butyl acetate, ethyl lactate, and 3-ethoxypropionate ester; aromatic hydrocarbons such as toluene and xylene; aliphatic hydrocarbons such as cyclohexane, methylcyclohexane, and heptane; cyclic ethers such as tetrahydrofuran and dioxane; and others.
These liquid media may be used alone, or two or more of them may be used in combination.
[0151]
The content of the liquid medium is preferably 30 mass% or more, more preferably 40 mass% or more, even more preferably 50 mass% or more, and preferably 95 mass% or less, more preferably 90 mass% or less, even more preferably 80 mass%
or less, based on 100 mass% of the ink composition. By adjusting the content of the liquid medium within such a range, solubility and dispersibility of the oxocarbon compound can be increased and it becomes easy to obtain the ink composition having a high concentration of the oxocarbon compound.
[0152]
The ink composition may comprise a resin component in addition to the liquid medium. By blending the resin component, viscosity, adhesiveness or the like of the ink composition can be improved. As the resin component, a known resin used for an ink composition can be used, and examples thereof include a (meth)acrylic resin, a (meth)acrylic urethane resin, a polyvinyl chloride resin, a polyvinylidene chloride resin, a polyolefin resin (e.g., polyethylene resin, polypropylene resin, and the like), a cycloolefin resin (including cycloolefin copolymer, norbomene resin, and the like), a petroleum resin, a rosin resin, a rosin ester resin, an urea resin, a melamine resin, an urethane resin, a styrene resin, a styrene-acrylic resin, a styrene-maleic acid resin, polyvinyl acetate, an ethylene-vinyl acetate resin, a vinyl acetal resin, a polyamide resin (e.g., nylon and the like), an aramid resin, a polyimide resin, a polyamide-imide resin, an alkyd resin, a phenolic resin, an epoxy resin, a polyester resin (e.g., polybutylene terephthalate resin, polyethylene terephthalate resin, polyarylate resin and the like), a polysulfone resin, a butyral resin, a polycarbonate resin, a polyether resin, an acrylonitrile butadiene styrene resin, an acrylonitrile-styrene copolymer, a cellulose derivative (e.g., ethyl cellulose, cellulose acetate, nitrocellulose, and the like), a silicone resin, a modified silicone resin (e.g., (meth)acrylic silicone resin, alkyl polysiloxane resin, silicone urethane resin, silicone polyester resin, silicone acrylic resin, and the like), a fluorine resin (e.g., fluorinated aromatic polymer, polytetrafluoroethylene, perfluoroalkoxy fluorine resin, fluorinated polyaryl ether ketone, fluorinated polyimide, fluorinated polyamic acid, fluorinated polyether nitrile, and the like), a diallyl phthalate resin, a cumarone-indene resin, a terpene phenol resin, a xylene resin, an alkyd resin, a maleic acid resin, a fumaric acid resin, and others. The blending amount of the resin component in the case of blending the resin component is preferably 1 mass% or more, more preferably 5 mass% or more, and preferably 60 mass% or less, more preferably 50 mass% or less, based on 100 mass% of the ink composition.
[0153]
The ink composition may contain various additives such as an ultraviolet absorber, a surface conditioner, a dispersant, a conductivity regulator, a polymerization inhibitor, a leveling agent, an antioxidant and the like, as needed. Details of these additives is made reference to the descriptions of additives in the resin composition.
[0154]
The ink composition can be produced by a known method. For example, the ink composition can be prepared by mixing a dye including the oxocarbon compound of the present invention, a liquid medium and, if necessary, a polymerizable monomer, a polymerization initiator and various additives, using a mixer such as a sand mill. If necessary, the thus obtained mixture may be filtered with a filter having a pore diameter of 3 gm or less or 1 i.tm or less.
[0155]
The ink composition of the present invention can be applied to various inks such as an ordinary solvent-based ink used for a screen printing ink, a gravure printing ink, an offset printing ink, a flexographic printing ink, an ink jet recording ink or the like, a light (ultraviolet light, visible light, infrared light) curable ink, and a water-based ink.
[0156]
The ink composition can be printed (applied) on any material, thereby forming a printed matter. A base material to be printed may be paper, cloth, wood, glass, concrete, stone, ceramics, resin, rubber, leather, steel, nonferrous metal (light metal, precious metal, rare metal, rare earth, copper, zinc, lead, tin, and the like), hair, skin or the like, for example. The shape of the base material to be printed is also not particularly limited, and examples thereof include a sheet, a plate, a sphere, an ellipsoid, a cubic, a column, a rod, a cone, a cylinder, a granular, a powder, a block, a particle agglomerate, a spicular, a fibrous, a hollow filamentous, a porous and others.
[0157]

[5. Others]
= In addition to the resin composition, the resin molding, the photothermal conversion material for laser welding, and the ink composition as described above, the oxocarbon compound of the present invention can be applied to photofixing materials utilizing light which is less likely to cause troubles due to pressurization or heating (e.g., electrostatic charge development toner for a flash fixing method), cosmetic materials having a near-infrared light absorbing or cutting function, materials for light detection and distance measurement (LIDAR) system, and the others.
EXAMPLES
[0159]
The present invention will be hereinafter described more specifically with reference to examples; however, the present invention is not restricted by these examples, and can be certainly put into practice after appropriate modifications within in a range meeting the gist of the above and the below, all of which are included in the technical scope of the present invention [0160]
(1) Synthesis of Dye Compounds (1-1) Synthesis Example 1 (Synthesis of Croconium Compound 1) 60 mL of hydrochloric acid was added into a 300 mL four-necked flask, the temperature in the flask was cooled to -10 C or lower, and while keeping the temperature in the flask not exceed 0 C, 5.13 g (0.024 mol) of 3-aminofluoranthene was added thereto and dissolved. After the exotherm subsided, a solution of 1.63 g (0.024 mol) of sodium nitrite in 11 g of distilled water was added dropwise over 1 hour while keeping the temperature in the flask at -10 C or lower. After completion of the dropwise addition, a solution of 26.63 g (0.118 mol) of tin chloride dihydrate dissolved in 27 mL of hydrochloric acid was added dropwise over 1 hour while keeping the temperature in the flask not exceed 0 C, thereby proceeding the reaction.
After completion of the reaction, cake obtained by filtration was dried at 60 C for 12 hours using a vacuum dryer, thereby obtaining 5.5 g of fluoranthene-3-hydrazine hydrochloride. The yield based on 3-aminofluoranthene was 87.2 mol%.
[0161]
Subsequently, in a 50 mL four-necked flask, 3.01 g (0.011 mol) of fluoranthene-3-hydrazine hydrochloride obtained above, 0.96 g (0.011 mol) of 3-methyl-2-butanone, and 20 g of 1-butanol as a solvent were placed and reacted at 60 C for 4 hours under nitrogen flow (5 mL/min) while stirring using a magnetic stirrer, thereby obtaining a condensed heterocyclic compound. After completion of the reaction, the solution containing the condensed heterocyclic compound was cooled to room temperature, filtered, and the obtained filtrate was transferred to a 200 mL
four-necked flask. 0.78 g (0.006 mol) of croconic acid and 20 g of toluene were added thereto, and the mixture was stirred using a magnetic stirrer under nitrogen flow (5 mL/min), and the reaction was carried out under reflux condition for 6 hours while removing water eluted using a Dean-Stark apparatus. After completion of the reaction, thus obtained reaction solution was concentrated with an evaporator, the obtained solid was purified by a column chromatography (developing solvent: chloroform), and the purified isolate was further recrystallized in methanol, thereby obtaining 0.45 g of a croconium compound 1, the objective product. The yield based on croconic acid was 12.2 mol%.
[0162]
The obtained compound was identified by a mass spectrometer ("LCMS-2020"
manufactured by Shimadzu Corporation, M/Z=50-2000, positive/negative simultaneous scanning). Specifically, about 1 mg of the obtained compound was applied to a glass rod and adhered thereto, ionized with a direct ionization unit (DART) ("DART-OS"
manufactured by Shimadzu Corporation, heater temperature: 500 C), and introduced into the mass spectrometer, whereby the mass spectrum of the compound was measured.

i [0163]
[Chemical Formula 20]
0 NH2 1. NaNO2aq 2. SnC12.2H20 v.
Conc HCI aq ohi 1 11 o APO butanol 411*.

o) ro HO OH , , 0 ___________________________ N. 11 NH HN / \
toluene butanol 011 0 0- \¨i110110 Croconium Compound 1 [0164]
(1-2) Synthesis Example 2 (Synthesis of Croconium Compound 2) A croconium compound 2 shown in Table 1 was obtained in the same manner as in the Synthesis Example 1, except that ethyl 2-methylacetoacetate was used instead of 3-methyl-2-butanone in the Synthesis Example 1. The yield based on croconic acid was 5.8 mol%.
[0165]
(1-3) Synthesis Example 3 (Synthesis of Croconium Compound 3) 4.45 g (0.022 mol) of 3-(trifluoromethyl)phenylacetone was placed in a 300 mL
four-necked flask under nitrogen flow, temperature in the flask was cooled to -

10 C or lower, and 19.06 g of hexamethyldisilazane lithium (1.3M tetrahydrofuran solution), 8.46 g (0.066 mol) of N,N'-dimethylpropylene urea, 2.77 g (0.022 mol) of manganese chloride and 4.14 g (0.024 mol) of benzyl bromide were sequentially added thereto while keeping the temperature in the flask not exceed 0 C, followed by stirring overnight without controlling the temperature. The resulting reaction solution was quenched with dilute hydrochloric acid, extracted with ethyl acetate, and washed three times with brine. The obtained organic phase was dehydrated with sodium sulfate, concentrated using an evaporator, and then the obtained solid was purified by a column chromatography (developing solvent: chloroform), thereby obtaining 5.0 g of 4-phenyl-3-(3-(trifluoromethyl)phenyl)butan-2-one. The yield based on 3-(trifluoromethyl)phenylacetone was 78.1 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 4-phenyl-3-(3-(trifluoromethyl)phenyl)butan-2-one was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 3 shown in Table 1. The yield based on croconic acid was 10.1 mol%.
[0166]
(1-4) Synthesis Example 4 (Synthesis of Croconium Compound 4) 5-Phenyl-3-(3-(trifluoromethyl)phenyl)pentan-2-one was obtained in the same manner as in the Synthesis Example 3, except that (2-iodoethyl)benzene was used instead of benzyl bromide in the Synthesis Example 3. The yield based on 3-(trifluoromethyl)phenylacetone was 86.6 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 5-phenyl-3-(3-(trifluoromethyl)phenyl)pentan-2-one was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 4 shown in Table 1. The yield based on croconic acid was 8.3 mol%.
[0167]
(1-5) Synthesis Example 5 (Synthesis of Croconium Compound 5) 3-(3,4-Dimethoxypheny1)-5-phenylpentan-2-one was obtained in the same manner as in the Synthesis Example 3, except that 3,4-dimethoxyphenylacetone was used instead of 3-(trifluoromethyl)phenylacetone and (2-iodoethyl)benzene was used instead of benzyl bromide in the Synthesis Example 3. The yield based on 3,4-dimethoxyphenylacetone was 95.1 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 3-(3,4-dimethoxypheny1)-5-phenylpentan-2-one was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 5 shown in Table 1. The yield based on croconic acid was 15.4 mol%.
[0168]
(1-6) Synthesis Example 6 (Synthesis of Croconium Compound 6) 3-(3-(Trifluoromethyl)phenyl)decan-2-one was obtained in the same manner as in the Synthesis Example 3, except that 1-iodoheptane was used instead of benzyl bromide in the Synthesis Example 3. The yield based on 3-(trifluoromethyl)phenylacetone was 89.1 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 3-(3-(trifluoromethyl)phenyl)decan-2-one was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 6 shown in Table 1.
The yield based on croconic acid was 9.2 mol%.
[0169]
(1-7) Synthesis Example 7 (Synthesis of Croconium Compound 7) A croconium compound 7 shown in Table I was obtained in the same manner as in the Synthesis Example 1, except that 1,1-diphenylacetone was used instead of 3-methyl-2-butanone in the Synthesis Example 1. The yield based on croconic acid was 1.8 mol%.
[0170]
(1-8) Synthesis Example 8 (Synthesis of Croconium Compound 8) Into a 300 mL four-necked flask placed in a water bath, 6.73 g (0.060 mol) of potassium tert-butoxide, 35 g of super dehydrated tetrahydrofuran, 3.32 g (0.020 mol) of fluorene, 3.52 g (0.040 mol) of ethyl acetate were sequentially added under nitrogen flow, while paying attention to heat generation, and then the mixture was stirred under reflux condition for 3 hours while heating by a hot water bath. After cooling the obtained reaction solution and quenching with dilute hydrochloric acid, the resultant was extracted with ethyl acetate and washed three times with brine. The obtained organic phase was dehydrated with sodium sulfate, concentrated with an evaporator, and the obtained solid was purified by a column chromatography (developing solvent:
chloroform), thereby obtaining 4.1 g of 9-acetyl-9H-fluorene. The yield based on fluorene was 97.6%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 9-acetyl-9H-fluorene was used instead of 3-methyl-2-butanone and tert-amyl alcohol was used instead of 1-butanol as a solvent in the Synthesis Example 1, thereby obtaining a croconium compound 8 shown in Table 1. The yield based on croconic acid was 30.5 mol%.

[0171]
(1-9) Synthesis Example 9 (Synthesis of Croconium Compound 9) 2-Bromo-9-acetyl-9H-fluorene was obtained in the same manner as in the Synthesis Example 8, except that 2-bromo-9H-fluorene was used instead of fluorene in the Synthesis Example 8. The yield based on 2-bromo-9H-fluorene was 97.1 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 2-bromo-9-acetyl-9H-fluorene was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 9 shown in Table 1. The yield based on croconic acid was 10.4 mol%.
[0172]
(1-10) Synthesis Example 10 (Synthesis of Croconium Compound 10) 2-Iodo-9-acetyl-9H-fluorene was obtained in the same manner as in the Synthesis Example 8, except that 2-iodo-9H-fluorene was used instead of fluorene in the Synthesis Example 8. The yield based on 2-iodo-9H-fluorene was 95.8 mol%.
The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 2-iodo-9-acetyl-9H-fluorene was used instead of 3-methy1-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 10 shown in Table 1. The yield based on croconic acid was 18.9 mol%.
[0173]
(1-11) Synthesis Example 11 (Synthesis of Croconium Compound 11) 2-Trifluoromethy1-9H-fluorene was synthesized using the method described in Gonda et al., "Efficient Copper-Catalyzed Trifluoromethylation of Aromatic and Heteroaromatic Iodides: The Beneficial Anchoring Effect of Boranes", Organic Letters, 16 (2014): 4268-4271. Then, 2-trifluoromethy1-9-acetyl-9H-fluorene was obtained in the same manner as in the Synthesis Example 8, except that 2-trifluoromethy1-9H-fluorene was used instead of fluorene in the Synthesis Example 8.
The yield based on 2-trifluoromethy1-9H-fluorene was 91.4 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 2-trifluoromethy1-9-acetyl-9H-fluorene was used instead of 3-methy1-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 11 shown in Table 2. The yield based on croconic acid was 10.1 mol%.

[0174]
(1-12) Synthesis Example 12 (Synthesis of Croconium Compound 12) 2-Cyano-9H-fluorene was synthesized using the method described in the Journal of Organic Chemistry, vol.69, p.987-990 (2004). Then, 2-cyano-9-acetyl-911-fluorene was obtained in the same manner as in the Synthesis Example 8, except that 2-cyano-9H-fluorene was used instead of fluorene in the Synthesis Example 8. The yield based on 2-eyano-9H-fluorene was 95.9 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 2-cyano-9-acetyl-9H-fluorene was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 12 shown in Table 2. The yield based on croconic acid was 12.4 mol%.
[0175]
(1-13) Synthesis Example 13 (Synthesis of Croconium Compound 13) 9-Acetyl-9H-2,7-dibromofluorene was obtained in the same manner as in the Synthesis Example 8, except that 2,7-dibromofluorene was used instead of fluorene in the Synthesis Example 8. The yield based on 2,7-dibromofluorene was 95.9 mol%.

The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 9-acetyl-9H-2,7-dibromofluorene was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 13 shown in Table 2. The yield based on croconic acid was 18.5 mol%.
[0176]
(1-14) Synthesis Example 14 (Synthesis of Croconium Compound 14) 2-Bromo-7-iodo-9-acetyl-9H-fluorene was obtained in the same manner as in the Synthesis Example 8, except that 2-bromo-7-iodo-911-fluorene was used instead of fluorene in the Synthesis Example 8. The yield based on 2-bromo-7-iodo-9H-fluorene was 95.9 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 2-bromo-7-iodo-9-acetyl-9H-fluorene was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 14 shown in Table 2.
The yield based on croconic acid was 19.3 mol%.

[0177]
(1-15) Synthesis Example 15 (Synthesis of Croconium Compound 15) 2,7-Di-tert-butyl-9-acetyl-9H-fluorene was obtained in the same manner as in the Synthesis Example 8, except that 2,7-di-tert-butyl-9H-fluorene was used instead of fluorene in the Synthesis Example 8. The yield based on 2,7-di-tert-butyl-9H-fluorene was 97.3 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 2,7-di-tert-butyl-9-acetyl-9H-fluorene was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 15 shown in Table 2.
.. The yield based on croconic acid was 9.3 mol%.
[0178]
(1-16) Synthesis Example 16 (Synthesis of Croconium Compound 16) 9-Acetyl-9H-fluorene was obtained by the method described in the Synthesis Example 8 and 9-acetyl-9H-2,7-dibromofluorene was obtained by the method described in the Synthesis Example 13. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 9-acetyl-9H-fluorene and 9-acety1-911-2,7-dibromofluorene were used in a molar ratio of 1:1 instead of 3-methy1-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 16 (mixture) shown in Table 2. The yield based on croconic acid was 12.1 mol%.
[0179]
(1-17) Synthesis Example 17 (Synthesis of Croconium Compound 17) 1-(1H-inden-1 -yl)ethan-l-one was obtained in the same manner as in the Synthesis Example 8, except that indene was used instead of fluorene in the Synthesis Example 8. The yield based on indene was 74.8 mol%. The synthesis procedures thereafter were conducted in the same manner as in the Synthesis Example 1, except that 1-(1H-indene-1-yl)ethan-1-one was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium Compound 17 shown in Table 2.
The yield based on croconic acid was 1.5 mol%.
[0180]

=
(1-18) Synthesis Example 18 (Synthesis of Croconium Compound 18) 9-Acetyl-9H-xanthene was obtained in the same manner as in the Synthesis Example 8, except that xanthene was used instead of fluorene in the Synthesis Example 8. The yield based on xanthene was 84.2 mol%. The synthesis procedures thereafter were conducted in the same manner as the Synthesis Example 1, except that 9-acetyl-91-1-xanthene was used instead of 3-methyl-2-butanone in the Synthesis Example 1, thereby obtaining a croconium compound 18 shown in Table 2. The yield based on croconic acid was 11.7 mol%.
[0181]
(1-19) Synthesis Example 19 (Synthesis of Comparative Croconium Compound 1) Into a 50 mL four-necked flask, 0.73 g (0.004 mol) of 2,3,3-trimethy1-4,5-benzo-314-indole, 0.25 g (0.002 mol) of croconic acid, and 10 g of 1-butanol and 10 g of toluene as solvents were added, and the mixture was reacted under reflux condition for 6 hours, while stirring under nitrogen flow (5 mL/min) using a magnetic stirrer and removing water eluted using a Dean Stark apparatus.
After completion of the reaction, the obtained reaction solution was concentrated with an evaporator, the obtained solid was purified by a column chromatography (developing solvent: chloroform), and the purified isolate was further recrystallized in methanol, whereby 0.30 g of a comparative croconium compound 1 shown in Table 2 was obtained. The yield based on croconic acid was 32.7 mol%.
[0182]
(1-20) Synthesis Example 20 (Synthesis of Comparative Phthalocyanine Compound 1) A comparative phthalocyanine compound 1 shown in Table 3 was obtained by the synthesis method described in Example 2 of Japanese Unexamined Patent Application Publication No. 2007-56105.
[0183]
[Table 1]

il ' Croconium Compound 1 Croconium Compound 2 o- --\ o o- o /---o o .

, 0 ---/ \ NH HN / \
7 , ¨ 0 0- HN 41 I I 7 od NH Q 0-...
W II"
Croconium Compound 3 Croconium Compound 4 .

= . 'a \ / . 41 lik li 41 --- 0 --.._ 4111 NH HN . it NH HN 41, It. SS 0 a al.
Croconium Compound 5 Croconium Compound 6 Me0 OMe Me0 OMe F3C CF3 . = 0-C7- 11 = 15 IP cr 1, NH HN 110fi. Olip 11 NH 0 a HN
OS =
=
II

_ Croconium Compound 7 Croconium Compound 8 SO e 0- IP 0 000 0- %to AI NH HN . = NH HN 110, OS 0 0- 10. .11. 0 0-IIP

Croconium Compound 9 Croconium Compound 10 0110, o- liPalli &IP o- AO
Br Br I I

11 NH HN . . NH 0 0_ HN

[0184]
[Table 2]

Croconium Compound 11 Croconium Compound 12 00 0- 1116.1 400. 0- 1Peop cF3 CF3 . CN CN
ON"
AI NH HN . NH HN 410, 0 a 11010 1.10. 0 0' 10.
Croconium Compound 13 Croconium Compound 14 411, Br Br 11, di I 0-1 Oa Ole 0-4110 41-.. ..-101 Br 0 Br Br 0 Br . NH HN 41 41 NH 0 0_ HN
OS 0, 0 0' lik 00 sell Croconium Compound 15 Croconium Compound 16 4. R x R y ii p fe 41. 00 t_Bru ip 10 Rx 0 --- Ry t-Bu --- 0 --- t-Bu . NH HN
.41 .

. NH HN 1141 0-Rx=H or Br Ry=H or Br . , Croconium Compound 17 Croconium Compound 18 41011, 0-- 0 - .
. NH HN 41 OP Ole ilk NH 0 0.
411.4I 0 0-11/ 1/4111.
, _________________________________________________________ Comparative Croconium Compound 1 2 \ NH CP HN / p 0 0_ [0185]
[Table 3]

Comparative Phthalocyanine Compound 1 Q /H C H
s * N N
N *
S
N-Cu-N
N
* *
H3_co) os [0186]
(2) Preparation of Resin (2-1) Preparation of Fluorinated Aromatic Resin Into a reactor equipped with a thermometer, a condenser tube, a gas inlet tube and a stirrer, 16.74 parts by mass of 4,4'-bis(2,3,4,5,6-pentafluorobenzoyl)diphenyl ether, 10.5 parts by mass of 9,9-bis(4-hydroxyphenyl)fluorene, 4.34 parts by mass of potassium carbonate and 90 parts by mass of dimethylacetamide were placed. The mixture placed in the reactor was heated to 80 C and reacted for 8 hours.
After completion of the reaction, the reaction solution was poured into 1% acetic acid aqueous solution while vigorously stirring the reaction solution with a blender.
The precipitated reaction product was separated by filtration, washed with distilled water and methanol, and then dried under reduced pressure, thereby obtaining a fluorinated aromatic resin. The fluorinated aromatic resin had a glass transition temperature (Tg) of 242 C and a number average molecular weight (Mn) of 70,770. The number average molecular weight was determined by a gel permeation chromatography and expressed by a polystyrene conversion value.
[0187]
(2-2) Preparation of Acrylic Resin Into a reactor equipped with a thermometer, a condenser tube, a gas inlet tube and a stirrer, 21.0 parts by mass of methyl a-allyloxymethyl acrylate (AMA), 9.0 parts by mass of N-phenylmaleimide and 45.0 parts by mass of ethyl acetate as a polymerization solvent were placed, and the temperature thereof was raised while stirring under a flow of nitrogen gas. After the temperature inside the reactor was stabilized at 70 C, 0.03 part by mass of an azo-based radical polymerization initiator (ABN-V available from Nippon Finechem Co., Ltd.) was added to start polymerization reaction. The reaction was carried out for 3.5 hours while maintaining the temperature inside the reactor at a range of 69 C to 71 C, and then cooled to room temperature.
Tetrahydrofuran was added thereto as a diluent solvent, and reprecipitation treatment was carried out using n-hexane as a poor solvent, and the precipitate was separated by suction filtration. The obtained precipitate was dried at 80 C under reduced pressure for 2 hours by using a reduced pressure drier, thereby obtaining an acrylic resin. A
weight average molecular weight of the acrylic resin measured by a gel permeation chromatography was 31,600. A glass transition temperature (Tg) of the acrylic resin measured by a differential scanning calorimeter was 152 C.
[0188]
(3) Production Example of Filter (Resin Laminated Substrate) (3-1) Production Example 1 2 parts by mass of a polycarbonate resin (Iupilon (registered trademark) E-2000, available from Mitsubishi Engineering-Plastics Corporation), 0.02 parts by mass of the croconium compound 7 and 18 parts by mass of chloroform were mixed to obtain a dye containing-resin composition. About 1 cc of this resin composition was dropped onto a glass substrate (D263Teco, available from SCHOTT AG, 60 mm x 60 mm x 0.3 mm, average transmittance 91%), and then coated thereon using a spin coater (1H-D7, available from Mikasa Co., Ltd.). The glass substrate on which a film of the resin composition was formed was dried at 100 C for 30 minutes under a nitrogen atmosphere by using an inert oven (available from Yamato Scientific Co., Ltd., DN
6101), thereby obtaining a resin laminated substrate 1 in which a resin layer was formed on a glass substrate. The thickness of the resin layer was about 2 pm.
[0189]
(3-2) Production Example 2 A resin laminated substrate 2 was produced in the same manner as in the Production Example 1, except that a cycloolefin resin (Zeonor (registered trademark) 141OR available from Zeon Corporation) was used instead of the polycarbonate resin as a resin used and dichlorobenzene was used instead of chloroform in the Production Example I.
[0190]
(3-3) Production Example 3 A resin laminated substrate 3 was produced in the same manner as in the Production Example 1, except that a norbomene resin (Arton (registered trademark) RX4500 available from JSR Corporation), which is one kind of the cycloolefin resin, was used instead of the polycarbonate resin as a resin used, the croconium compound 8 was used instead of the croconium compound 7, and toluene was used instead of chloroform in the Production Example 1.
[0191]
(3-4) Production Example 4 A resin laminated substrate 4 was produced in the same manner as in the Production Example 1, except that a cycloolefin copolymer (Topas (registered trademark) 5013 available from Polyplastics Co., Ltd.), which is one kinds of the cycloolefin resin, was used instead of the polycarbonate resin as a resin used, the croconium compound 8 was used instead of the croconium compound 7, and methyl .. cyclohexane was used instead of chloroform in the Production Example 1.
[0192]
(3-5) Production Example 5 A resin laminated substrate 5 was produced in the same manner as in the Production Example 1, except that the fluorinated aromatic resin prepared in the above (2-1) was used instead of the polycarbonate resin as a resin used, the croconium compound 8 was used instead of the croconium compound 7, and toluene was used instead of chloroform in the Production Example I.
[0193]
(3-6) Production Example 6 A resin laminated substrate 6 was produced in the same manner as in the Production Example 1, except that the acrylic resin prepared in the above (2-2) was used instead of the polycarbonate resin as a resin used, the croconium compound 8 was used instead of the croconium compound 7, and toluene was used instead of chloroform in the Production Example 1.
[0194]
(3-7) Comparative Production Example 1 A comparative resin laminated substrate 1 was produced in the same manner as in Production Example 1, except that the comparative phthalocyanine compound 1 was used instead of the croconium compound 7 in the Production Example 1.
[0195]
(4) Evaluation (4-1) Spectroscopic Measurement of Dye Compounds and Resin Laminated Substrates A chloroform solution of each of the dye compounds obtained in the Synthesis Examples 1 to 20 was prepared, and an absorption spectrum (a transmittance spectrum) in a wavelength range of 400 nm to 1100 nm was measured. The concentration of the chloroform solution of the dye compound was adjusted so that the transmittance at the maximum absorption wavelength was 10% ( 0.05%), the wavelength transmittance was measured with a spectrophotometer (UV-1800 manufactured by Shimadzu Corporation) at a pitch of 1 nm, and a wavelength at which the absorption was maximum in the wavelength range of 400 nm to 1100 nm (that is referred to as "maximum absorption wavelength 2,,max"), a wavelength at which the transmittance was 30% on the longer wavelength side of the maximum absorption wavelength (that is referred to as "%T30"), an average transmittance at the wavelength range of 400 run to 700 nm (that is referred to as "visible light transmittance"), and a transmittance at the wavelength of 400 nm (that is referred to as "%T(400nm)") were determined. In addition, with respect to each of the resin laminated substrates produced in the Production Examples 1 to 6 and the Comparative Production Example 1, an absorption spectrum (a transmittance spectrum) in a wavelength range of 400 nm to 1100 nm was measured in the same manner as the above and the maximum absorption wavelength Xmax, %T30, visible light transmittance, %T(400nm) under the condition that the transmittance at the maximum absorption wavelength was 10% ( 0.05%) were determined.
[0196]
Results of the spectroscopic measurement of the respective dye compounds in a chloroform solution are summarized in Table 4, and transmittance spectra of the croconium compound 1, the comparative croconium compound 1, and the comparative phthalocyanine compound 1 are shown in Fig. 1. In the croconium compounds 1 to 18, a total number of it electrons in the ring A and the substituent R7 was 16, the maximum absorption wavelength Xmax was 892 nm to 934 nm, %T30 was 918 nm to 963 nm, the visible light average transmittance was 85.2% to 92.2%. Meanwhile, in the comparative croronium compound 1, a total number of it electrons in the ring A
and the substituent R7 was 10, the maximum absorption wavelength Xmax was 810 nm, %T30 was 830 nm, and the visible light average transmittance was 92.8%. Linear interpolation of the relationship between the number of it electrons and the wavelength of %T30 in the croconium compound 1 (the croconium compound having the lowest wavelength %T30 among the croconium compounds 1 to 18) and the comparative croconium compound 1 leads to the fact that the wavelength of %T30 becomes 850 nm or higher and light in the wavelength range exceeding 850 nm can be effectively absorbed when the number of it electron is 12 or more. When the wavelength of %T30 is 850 nm or higher, it can be suitably used for security inks or laser welding applications, for example. Though the comparative phthalocyanine compound 1 had the maximum absorption wavelength Xmax of 904 nm and was capable of absorbing light in the wavelength range more than 850 nm, it had a low visible light average transmittance of 80.8%, which was somewhat inferior in terms of invisibility.
[0197]
[Table 4]

i =
, , Visible Light 2,max %130 Average %T(400nm) Transmittance _ Croconium Compound 1 892 nm 918 nm 91.9% 92.2%
Croconium Compound 2 916 nm 948 nm 88.2% 81.3%
_ Croconium Compound 3 921 nm 946 nm 91.7% 91.6%
Croconium Compound 4 915 nm 944 nm 89.2% 85.3%
-Croconium Compound 5 909 nm 937 nm 86.5% 80.2%
Croconium Compound 6 913 nm 938 nm 89.4% 82.5%
Croconium Compound 7 923 nm 950 nm 92.0% 90.9%
Croconium Compound 8 921 nm 949 nm 91.3% 90.2%
Croconium Compound 9 . 927 nm 956 nm 90.0% 87.7%
Croconium Compound 10 , 928 nm 957 nm 90.5% 89.1%
Croconium Compound 11 927 nm 956 nm 89.6% 86.8%
_ Croconium Compound 12 931 nm 961 nm 90.1% 88.0%
Croconium Compound 13 934 nm 963 nm 90.2% 88.9%
_ Croconium Compound 14 932 nm 963 nm 87.2% 83.0%
, Croconium Compound 15 920 nm 950 nm 85.3% 80.1%
_ Croconium Compound 16 926 nm 956 nm 90.7% 88.5%
-Croconium Compound 17 918 nm 949 nm 85.2% 80.9%
, Croconium Compound 18 922 nm 951 nm 92.2% 90.3%
, Comp. Croconium Compound 1 , 810 nm 830 nm 92.8% 93.0%
,..
Comp. Phthalocyanine Compound 1 904 nm 934 nm 80.8%
75.5%
-[0198]
Table 5 summarizes the spectroscopic measurement results of the resin laminated substrates. The resin laminated substrates 1 and 2 contained the croconium compound 7 as a dye, the resin laminated substrates 3 to 6 contained the croconium compound 8 as a dye, and the comparative resin laminated substrate 1 contained the comparative phthalocyanine compound 1 as a dye. Regardless of the kind of resin, the value of the maximum absorption wavelength Xmax of the resin laminated substrate was almost equal to that in chloroform solution. The visible light transmittances of the resin laminated substrates 1 to 6 were higher than that of the comparative resin laminated substrate 1. The resin laminated substrates 1 to 6 can be suitably applied to, for example, an optical filter of an image sensing device for night vision.
[0199]
[Table 5]
Visible Light Amax %130 Average %T(400nm) Transmittance Resin Laminated Substrate 1 930 nm 962 nm 82.1% 80.7%
Resin Laminated Substrate 2 939 nm 977 nm 77.1% 75.6%
Resin Laminated Substrate 3 926 nm 958 nm 85.0% 83.6%
Resin Laminated Substrate 4 934 nm 957 nm 79.6% 79.4%
Resin Laminated Substrate 5 928 nm 952 nm 84.2% 83.3%
Resin Laminated Substrate 6 923 nm 984 nm 74.9% 71.3%
Comp. Resin Laminated Substrate 1 902 nm 940 nm 69.2%
61.0%
[0200]
(4-2) Storage Stability of Ink Composition 5 mg of the croconium compound 7 obtained in the Synthesis Example 7 was weighed and diluted with chloroform to adjust 100 mL. 5 mL of the obtained chloroform solution was taken out using a whole pipette and further diluted with chloroform to adjust 50 mL, whereby an ink composition 1 was prepared. The obtained ink composition 1 was stored for 1 month under shading at room temperature.
With respect to the ink composition 1 immediately after preparation and after storage for one month, an absorption spectrum (a transmittance spectrum) in wavelength range of 400 nm to 1100 nm was measured in the same manner as the above, and the transmittance at the maximum absorption wavelength and the visible light transmittance were determined respectively. Degradation on the spectroscopic characteristics of the ink composition 1 was not recognized even after one month storage, and it was confirmed that the ink composition 1 was excellent in storage stability.
[0201]
[Table 6]
Transmittance Visible Light Storage Period (at max. absorption Average wavelength) Transmittance Immediately 8.6% 92.0%
after Preparation Ink Composition 1 One-month Storage 8.6% 92.0%
INDUSTRIAL APPLICABILITY
[0202]
The oxocarbon compound of the present invention is useful as, for example, an optical filter for a semiconductor light receiving element having a near-infrared light absorbing or cutting function, a near-infrared absorbing film or a near-infrared absorbing plate that shields a heat ray for energy saving, an information indication material such as a security ink and an invisibnle bar code ink, a material for a solar cell utilizing visible light and near-infrared light, a specific wavelength absorption filter for a plasma display panel (PDP) or CCD, a photothermal conversion material for laser welding, a photofixing material utilizing light which is less likely to cause troubles due to pressurization or heating (e.g., electrostatic charge development toner for a flash fixing method), a cosmetic material having a near-infrared light absorbing or cutting function, a material for light detection and distance measurement (LIDAR) system, and the like.

Claims (7)

We Claim:

1. An oxocarbon compound represented by the following formula (1) or (2):
wherein R1 to R4 each independently represent a structural unit represented by the following formula (3):
wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these ring structures optionally having a substituent, wherein the substituent is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group, cyano group, a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring, wherein the organic group is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group and cyano group, and the polar functional group is selected from the group consisting of a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2), and a total number .pi. electrons contained in the ring A and R7 is 12 or more.

2. The oxocarbon compound according to claim 1, wherein R5 and R6 each independently represent hydrogen atom, an alkyl group optionally having a substituent, an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent or an aryloxycarbonyl group optionally having a substituent, or R5 and R6 are linked to each other to form a hydrocarbon ring optionally having a substituent and/or a condensed ring structure, or a heterocyclic ring optionally having a substituent and/or a condensed ring structure, and R7 represents hydrogen atom, an alkyl group optionally having a substituent or an aryl group optionally having a substituent.

3. A resin composition comprising the oxocarbon compound according to claim 1 or claim 2 and a resin component.

4. The resin composition according to claim 3, further comprising a liquid medium.

5. An ink composition comprising the oxocarbon compound according to claim or claim 2 and a liquid medium.

6. A condensed heterocyclic compound represented by the following formula (5):
wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these rings optionally having a substituent, R5 represents an alkyl group optionally having a substituent, an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent, or an aryloxycarbonyl group optionally having a substituent, R6 represents an aryl group optionally having a substituent, an aralkyl group optionally having a substituent, an alkoxycarbonyl group optionally having a substituent, or an aryloxycarbonyl group optionally having a substituent, or R5 and R6 are linked to each other to form a hydrocarbon ring optionally having a substituent and/or a condensed ring structure or a heterocyclic ring optionally having a substituent and/or a condensed ring structure, R7 represents hydrogen atom, an organic group or a polar functional group, the substituent is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfmyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group, cyano group, a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, the organic group is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfmyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group and cyano group, the polar functional group is selected from the group consisting of a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, and a total number of .pi. electrons contained in the ring A and R7 is 12 or more.

7. A process for producing an oxocarbon compound comprising the step of reacting a condensed heterocyclic compound represented by the following formula (5):
wherein ring A represents an aromatic hydrocarbon ring optionally having a substituent, an aromatic heterocyclic ring optionally having a substituent, or a condensed ring containing these rings optionally having a substituent, wherein the substituent is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group, cyano group, a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, R5 to R7 each independently represent hydrogen atom, an organic group or a polar functional group, or R5 and R6 are linked to each other to form a ring, wherein the organic group is selected from the group consisting of an alkyl group, an alkoxy group, an alkylthio group, an alkoxycarbonyl group, an alkylsulfonyl group, an aryl group, an aralkyl group, an aryloxy group, an arylthio group, an aryloxycarbonyl group, an arylsulfonyl group, an arylsulfinyl group, a heteroaryl group, an amido group, a sulfonamido group, an ethylene-containing group, an imine-containing group, carboxy group, a benzothiazole group, a halogenoalkyl group and cyano group, and the polar functional group is selected from the group consisting of a halogeno group, hydroxyl group, nitro group, an amino group and sulfo group, and a total number of .pi. electrons contained in the ring A and R7 is 12 or more, with squaric acid or croconic acid to obtain an oxocarbon compound represented by the following formula (1) or the following formula (2):

wherein R1 to R4 each independently represent a structural unit represented by the following formula (3):
wherein ring A and R5 to R7 each have the same meaning as described above, * represents a bonding site to a 4-membered ring in formula (1) or a 5-membered ring in formula (2), and a total number of .pi. electrons contained in the ring A and R7 is 12 or more.