Near-infrared fluorescent colorant composition

Abstract

The present invention provides an active energy ray curable ink composition containing a near-infrared fluorescent dye that exhibits strong and long-lasting fluorescence emission intensity in the near-infrared region and is visible under near-infrared light. [Solution] An active energy ray curable ink composition containing a near-infrared fluorescent dye and a polymerizable compound, wherein the near-infrared fluorescent dye is one or more selected from the group consisting of compounds represented by the following general formulas (I1) to (I4). JPEG2026110311000044.jpg65166

Description

[Technical Field]

[0001] The present invention relates to a colorant composition that emits near-infrared fluorescence, and an ink composition containing the colorant composition. [Background technology]

[0002] Invisible inks, invisible to the naked eye, are used for various purposes, including food traceability (clearly identifying the origin, raw materials, processing, manufacturing, and distribution of products) and identification and counterfeit prevention of various industrial products. Invisible inks, also known as stealth inks, concealed inks, or invisible inks, can become visible through heating or chemical reactions, but the most common type is the one that becomes visible upon light irradiation, due to its ease of handling and ability to maintain design integrity and confidentiality. Invisible inks, which become visible when irradiated with light, can be broadly classified into two types: ultraviolet-type inks that fluoresce when irradiated with ultraviolet light, and infrared-type inks that reflect or absorb infrared light, or fluoresce when irradiated with infrared light. Ultraviolet-type invisible inks are usually made visible to the naked eye when irradiated with high-frequency ultraviolet light (black light). However, ultraviolet light is harmful, and there are problems with detecting inks printed inside products or components using ultraviolet light. Infrared invisible inks are invisible to the naked eye when irradiated and can only be visualized using specific equipment, thus improving confidentiality. They are also easier to detect than ultraviolet light when printed inside products or components, and are less harmful than ultraviolet light. For example, Patent Document 1 discloses an infrared phosphor, in which an organic substance that absorbs wavelengths in the infrared region is supported on a black pigment that reflects or transmits light in the infrared region, and an ink composition containing such an infrared phosphor. It is stated that this can be used in ordinary black and white barcodes and can be read by barcode scanners, and can also be read as an infrared phosphor regardless of the background color.

[0003] In recent years, near-infrared fluorescent dyes have been used for the purpose of identifying and preventing counterfeiting of various industrial products, and are also used in medical applications such as bioimaging probes and diagnostic reagents. To ensure visibility, it is desirable that the near-infrared fluorescent dye itself strongly absorbs light in the near-infrared region and emits strong fluorescence (high emission quantum yield). Patent document 2 discloses a resin composition containing a specific near-infrared fluorescent dye, which is a BODIPY dye or a DPP-based boron complex having a boron dipyrromethene skeleton, and a resin, with a maximum absorption wavelength of 700 nm or higher, and it is stated that a near-infrared fluorescent resin composition with strong emission intensity and a molded article thereof can be obtained. On the other hand, Patent Document 3 proposes a curable ink composition containing a specific near-infrared absorbing dye, and discloses that pixels of a near-infrared absorbing filter are formed using an inkjet ink containing such a curable ink composition. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 08-183952 [Patent Document 2] International Publication No. 2015 / 056779 [Patent Document 3] Japanese Patent Publication No. 2011-68731 [Overview of the project] [Problems that the invention aims to solve]

[0005] The ink composition described in Patent Document 1 is said to allow the infrared phosphor to be read even when printed in layers, but if phosphors with similar excitation fluorescence wavelengths are used, individual identification may be difficult from the standpoint of traceability, etc. Patent Document 2 discloses a near-infrared fluorescent resin composition, which requires consideration of manufacturing costs, environmental aspects, and simplification of the manufacturing process. The curable ink composition described in Patent Document 3 is only intended for applications that absorb wavelengths in the near-infrared region, and does not mention fluorescence at all. Therefore, there is a need for an infrared light type invisible ink with improved versatility. As a result of intensive studies, the inventors of the present invention have found that a composition containing a specific near-infrared fluorescent dye and a polymerizable compound as constituent components, and in which such a near-infrared fluorescent dye is preferably present in a dissolved state, can solve the drawbacks of ultraviolet light type invisible inks and is useful as an invisible ink for traceability and anti-counterfeiting applications, particularly an active energy ray curable ink composition. An object of the present invention is to provide an active energy ray curable ink composition containing a near-infrared fluorescent dye that has a strong fluorescence emission intensity in the near-infrared light region and is maintained over a long period, and is visible with near-infrared light.

Means for Solving the Problems

[0006] The present invention has the following aspects. [1] An active energy ray curable ink composition containing a near-infrared fluorescent dye and a polymerizable compound, wherein the near-infrared fluorescent dye has the following general formula (I1)

[0007] [Chemical formula]

[0008] [In formula (I1), R e , and R b together with the nitrogen atom to which R a is bonded and the carbon atom to which R b is bonded form a condensed aromatic ring formed by condensation of an aromatic 5-membered ring, an aromatic 6-membered ring, or 2 to 3 5-membered rings or 6-membered rings; R c and R d together with the nitrogen atom to which R c is bonded and the carbon atom to which R d is bonded form a condensed aromatic ring formed by condensation of an aromatic 5-membered ring, an aromatic 6-membered ring, or 2 to 3 5-membered rings or 6-membered rings; R e and R f represent a halogen atom or an oxygen atom; R g represents a hydrogen atom or an electron-withdrawing group. However, R eand R f If it is an oxygen atom, R e , R e The boron atom that bonds with R a , and R a The nitrogen atoms to which it is bonded may together form a ring, R f , R f The boron atom that bonds with R c , and R c The nitrogen atoms to which it is bonded may together form a ring. R e If it is an oxygen atom and does not form a ring, then R e R is an oxygen atom having a substituent, f If it is an oxygen atom and does not form a ring, then R f is an oxygen atom having a substituent. ] Compounds represented by ] The following general formula (I2)

[0009] [ka]

[0010] [In formula (I2), R a ~R f The compound shown is as defined above. The following general formula (I3)

[0011] [ka]

[0012] [In formula (I3), R h and R i R h The nitrogen atom and R to which it is bonded i Together with the carbon atom to which it is bonded, it forms an aromatic five-membered ring, an aromatic six-membered ring, or a condensed aromatic ring formed by the condensation of two to three five-membered or six-membered rings; R j and R k R j The nitrogen atom and R to which it is bonded kTogether with the carbon atom to which it is bonded, it forms an aromatic five-membered ring, an aromatic six-membered ring, or a condensed aromatic ring formed by the condensation of two to three five-membered or six-membered rings; R l , R m , R n , and R o These are halogen atoms, C, independently of each other. 1-20 Alkyl alkyl group, C 1-20 R represents an alkoxy group, an aryl group, or a heteroaryl group; p and R q These are hydrogen atoms, halogen atoms, and C, which are independent of each other. 1-20 Alkyl alkyl group, C 1-20 R represents an alkoxy group, an aryl group, or a heteroaryl group. r and R s These independently represent a hydrogen atom or an electron-withdrawing group. Compounds represented by ], and The following general formula (I4)

[0013] [ka]

[0014] [In formula (I4), R h ~R q [This is as defined above] One or more compounds selected from the group consisting of the compounds shown, An active energy ray curable ink composition wherein the maximum fluorescence wavelength of the near-infrared fluorescent dye is 650 nm or higher. [2] The active energy ray curable ink composition of [1], wherein the near-infrared fluorescent dye is dissolved. [3] The active energy ray curable ink composition according to [1] or [2], wherein the polymerizable compound has the function of dissolving the near-infrared fluorescent dye. [4] An active energy ray curable ink composition according to any of [1] to [3], wherein the polymerizable compound does not have a vinyl group directly bonded to a nitrogen atom. [5] Any of the active energy ray curable ink compositions [1] to [4], wherein the content of the near-infrared fluorescent dye is in the range of 50 to 500 ppm relative to the total mass of the active energy ray curable ink composition. [6] Furthermore, an active energy ray curable ink composition of any of [1] to [5], which contains a photopolymerization initiator. [7] A solvent-free active energy ray curable ink composition according to any of [1] to [6]. [8] An active energy ray curable ink composition of any of [1] to [7], which is formed by an inkjet method. [9] A cured product of any of the active energy ray curable ink compositions from [1] to [8]. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide an active energy ray curable ink composition containing a near-infrared fluorescent dye that exhibits strong and long-lasting fluorescence emission intensity in the near-infrared light region and is visible under near-infrared light. [Modes for carrying out the invention]

[0016] The present invention relates to an active energy ray curable ink composition containing a near-infrared fluorescent dye and a polymerizable compound, wherein the near-infrared fluorescent dye is one or more compounds selected from the group consisting of compounds represented by the above-mentioned general formulas (I1), (I2), (I3), and (I4), and the maximum fluorescence wavelength of the near-infrared fluorescent dye is 650 nm or more, and the active energy ray curable ink composition (hereinafter simply referred to as "the ink composition of the present invention"). The ink composition of the present invention exhibits strong fluorescence emission intensity in the near-infrared light region, and this fluorescence emission intensity is maintained over a long period of time. In other words, the decrease in fluorescence intensity of the ink composition of the present invention is suppressed, and fluorescence observation is easily visible under near-infrared light over a long period of time, making it suitable for use in traceability and anti-counterfeiting applications.

[0017] In the ink composition of the present invention, the maximum fluorescence wavelength of the near-infrared fluorescent dye is preferably 650 nm or more and 900 nm or less. Furthermore, the maximum absorption wavelength of the near-infrared fluorescent dye is preferably 900 nm or less. More preferably, the maximum absorption wavelength of the near-infrared fluorescent dye is 850 nm or less, and even more preferably 800 nm or less. More preferably, the maximum absorption wavelength of the near-infrared fluorescent dye is 700 nm or more. When the maximum absorption wavelength of the near-infrared fluorescent dye is within the above range, it is easier to increase the excitation fluorescence intensity when irradiated with light in the near-infrared wavelength range. In other words, in the ink composition of the present invention, it is more preferable that the maximum fluorescence wavelength is 650 nm or more and 900 nm or less, and the maximum absorption wavelength of the near-infrared fluorescent dye is 900 nm or less.

[0018] In the ink composition of the present invention, it is preferable that the near-infrared fluorescent dye is dissolved. In other words, in the ink composition of the present invention, it is preferable that the near-infrared fluorescent dye exists in a dissolved state. In the curable composition disclosed in Patent Document 3, it is disclosed that using a near-infrared absorbing dye in a fine particle dispersion state improves the durability of the compound and has the advantage of extending the maximum absorption wavelength, and the form of the near-infrared absorbing dye is determined with near-infrared absorption filter applications in mind. On the other hand, in the ink composition of the present invention, the concentration of the near-infrared fluorescent dye is low and it contains a polymerizable compound, described later, that easily dissolves the near-infrared fluorescent dye, so the composition tends to have the near-infrared fluorescent dye in a dissolved state. As a result, fluorescence quenching due to aggregation is less likely to occur. Therefore, it is presumed that an ink composition having high fluorescence emission intensity even after curing with active energy rays can be obtained.

[0019] The total content of the near-infrared fluorescent dye and the polymerizable compound in the ink composition of the present invention is preferably 20% by mass or more, and more preferably 25% by mass or more. The total content of the near-infrared fluorescent dye and the polymerizable compound in the ink composition of the present invention is preferably 95% by mass or less, and more preferably 90% by mass or less.

[0020] Furthermore, the content of the near-infrared fluorescent dye in the ink composition of the present invention is preferably in the range of 50 to 500 ppm relative to the total mass of the ink composition of the present invention, and more preferably in the range of 50 ppm or more and less than 100 ppm. When the content of the near-infrared fluorescent dye in the ink composition of the present invention is within the above range, it is easier to suppress the phenomenon of concentration quenching that tends to occur when the concentration of the near-infrared fluorescent dye is high. In addition, since the near-infrared fluorescent dye is easily dissolved in the ink composition of the present invention, excitation fluorescence by irradiation with near-infrared light is easily emitted, increasing the fluorescence emission intensity, and the decrease in fluorescence emission intensity is suppressed, making it easier to maintain over a long period of time. The near-infrared fluorescent dyes and polymerizable compounds constituting the ink composition of the present invention will be described below.

[0021] [Near-infrared fluorescent dyes] The near-infrared fluorescent dye in the ink composition of the present invention is one or more compounds selected from the group consisting of compounds represented by the following general formulas (I1), (I2), (I3), and (I4). These compounds may hereinafter be referred to as "the near-infrared fluorescent dye according to the present invention."

[0022] [ka]

[0023] [ka]

[0024] In general formula (I1) or general formula (I2), R a and R b R a The nitrogen atom and R to which it is bonded b It forms an aromatic ring consisting of 1 to 3 rings together with the carbon atom to which it is bonded. Similarly, in general formula (I1) or general formula (I2), R c and R d R c The nitrogen atom and R to which it is bonded d It forms an aromatic ring consisting of 1 to 3 rings together with the carbon atom to which it is bonded. a and R b, and R c and R d The aromatic rings formed by each are either 5-membered or 6-membered rings. Compounds represented by general formula (I1) or general formula (I2) are R a and R b , R c and R d Each of these compounds has a ring structure in which the aromatic rings it forms are fused by a ring containing a boron atom bonded to two nitrogen atoms. In other words, the compounds represented by general formula (I1) or general formula (I2) have a robust fused ring structure consisting of a broad conjugated plane.

[0025] In general formula (I3) or general formula (I4), R h and R i R h The nitrogen atom and R to which it is bonded i It forms an aromatic ring consisting of 1 to 3 rings together with the carbon atom to which it is bonded. Similarly, in general formula (I3) or general formula (I4), R j and R k R j The nitrogen atom and R to which it is bonded k It forms an aromatic ring consisting of 1 to 3 rings together with the carbon atom to which it is bonded. h and R i , and R j and R k The aromatic rings formed by each are either 5-membered or 6-membered rings. Compounds represented by general formula (I3) or general formula (I4) are R h and R i A triring is formed by the condensation of an aromatic ring, a ring containing a boron atom bonded to two nitrogen atoms, and a five-membered heteroring containing one nitrogen atom, and R j and R k The compound has a ring structure in which at least six rings are fused together, i.e., a ring structure in which an aromatic ring formed by the compound is fused with a ring containing a boron atom bonded to two nitrogen atoms and a five-membered heteroring containing one nitrogen atom, and these three rings are fused together with the five-membered heterorings. Thus, the compound represented by general formula (I3) or general formula (I4) has a robust fused ring structure consisting of a very broad conjugated plane.

[0026] R a and R b , Rc and R d , R h and R i , and R j and R k Examples of aromatic rings formed by these rings include pyrrole rings, imidazole rings, pyrazole rings, oxazole rings, thiazole rings, pyridine rings, pyrimidine rings, pyridazine rings, isoindole rings, indole rings, indazole rings, purine rings, perimidine rings, thienopyrrole rings, phlopyrrole rings, pyrrolothiazole rings, and pyrrolooxazole rings. These aromatic rings may have no substituents or may have one or more substituents. Since the maximum fluorescence wavelength is extended to the near-infrared region, it is particularly preferable that the number of ring fusions of the aromatic ring be 2 or 3 in the case of general formula (I1) or general formula (I3), and more preferably 2 from the standpoint of complexity in synthesis. However, even when the number of ring fusions of the aromatic ring is 1, it is possible to extend the wavelength by devising substituents on the ring or on the boron. Furthermore, in the case of general formula (I2) or general formula (I4), the wavelength can be extended to the near-infrared region simply by attaching a substituted aryl group or heteroaryl group.

[0027] Examples of such substituents include halogen atoms such as fluorine, chlorine, bromine, and iodine; Alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, t-butyl (tert-butyl), pentyl, isoamyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl groups; alkenyl groups such as vinyl, aryl, 1-propenyl, isopropenyl, 2-butenyl, 1,3-butadienyl, 2-pentenyl, and 2-hexenyl groups; alkynyl groups such as ethynyl, 1-propynyl, 2-propynyl, isopropynyl, 1-butynyl, and isobutynyl groups; and other linear, branched, or cyclic alkyl, alkenyl, and alkynyl groups having 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms; Alkyl sulfonyl groups, alkylthio groups, alkoxycarbonyl groups, alkylamide carbonyl groups, alkylcarbonylamide groups, acyl groups, monoalkylsilyl groups, dialkylsilyl groups, trialkylsilyl groups, monoalkoxysilyl groups, dialkoxysilyl groups, and trialkoxysilyl groups having the aforementioned alkyl portion; Alkoxy groups such as methoxy group, ethoxy group, propyloxy group, isopropyloxy group, n-butyloxy group, isobutyloxy group, t-butyloxy group, pentyloxy group, isoamyloxy group, hexyloxy group, heptyloxy group, octyloxy group, nonyloxy group, decyloxy group, undecyloxy group, and dodecyloxy group; Monoalkylamino groups such as methylamino group, ethylamino group, propylamino group, isopropylamino group, butylamino group, isobutylamino group, t-butylamino group, pentylamino group, and hexylamino group; dialkylamino groups such as dimethylamino group, diethylamino group, dipropylamino group, diisopropylamino group, dibutylamino group, diisobutylamino group, dipentylamino group, dihexylamino group, ethylmethylamino group, methylpropylamino group, butylmethylamino group, ethylpropylamino group, and butylethylamino group; Aryl groups such as phenyl, naphthyl, indenyl, and biphenyl groups; Five-membered heteroaryl groups such as pyrrolyl, imidazolyl, pyrazolyl, thienyl, furanyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, and thiadiazole groups; six-membered heteroaryl groups such as pyridinyl, pyrazinyl, pyrimidinyl, and pyridadinyl groups; condensed heteroaryl groups such as indolyl, isoindolyl, indazolyl, quinolidinyl, quinolinyl, isoquinolinyl, benzofuranyl, isobenzofuranyl, clomenyl, benzoxazolyl, benzoisoxazolyl, benzothiazolyl, and benzoisothiazolyl groups; Examples thereof include a nitro group, a cyano group, a hydroxy group, a carboxyl group, an aldehyde group, a sulfonic acid group, a halogenosulfonyl group, a thiol group, an isocyanate group, a thioisocyanate group, an amino group, a silyl group, etc. These substituents may further have a substituent. Among them, a cyano group, a hydroxy group, a carboxyl group, an alkylthio group, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an amide group, an alkylsulfonyl group, a fluorine atom, a chlorine atom, an aryl group, or a heteroaryl group is preferable.

[0028] The maximum absorption wavelength of the fluorescent dye can be made longer by introducing an electron-donating group and an electron-withdrawing group at appropriate positions in the molecule to narrow the band gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO). For example, among the compounds represented by the general formula (I1), for the aromatic rings formed by R a and R b and for the aromatic rings formed by R c and R d introduce an electron-donating group, and introduce an electron-withdrawing group to R g so that the maximum absorption wavelength and the maximum fluorescence wavelength of the compound can be made longer. Similarly, among the compounds represented by the general formula (I3), for the aromatic rings formed by R h and R i and for the aromatic rings formed by R j and R k introduce an electron-donating group, and when R p and R q form an aromatic ring, introduce an electron-donating group to the aromatic ring, or introduce an electron-withdrawing group to R r and R s so that the maximum absorption wavelength and the maximum fluorescence wavelength of the compound can be made longer. By combining these designs, it is possible to adjust to the target wavelength. For the compound represented by the general formula (I2) having an azaBODIPY skeleton, for the aromatic rings formed by R a and R b and for the aromatic rings formed by R c and R dThe aromatic ring formed by this has a skeleton that absorbs at relatively long wavelengths even when unsubstituted. Unlike the compound represented by general formula (I1), in this skeleton, the bridging portion of the pyrrole is a nitrogen atom, so substituents cannot be introduced on the nitrogen, but the pyrrole portion (R a and R b The aromatic ring and R that are formed c and R d By introducing an electron-donating group to the aromatic ring formed by the compound, the maximum absorption wavelength and maximum fluorescence wavelength can be extended to longer wavelengths. Similarly, in the case of a compound represented by general formula (I4), the pyrrole moiety (R h and R i The aromatic ring and R that are formed j and R k Introducing an electron-donating group to the aromatic ring formed by, or R p and R q If the compound is an aromatic ring, introducing an electron-donating group to the aromatic ring can extend the maximum absorption wavelength and maximum fluorescence wavelength of the compound to longer wavelengths.

[0029] Therefore, R a and R b , R c and R d , R h and R i , and R j and R k The substituents on the aromatic rings formed by each of these are preferably electron-donating groups. The introduction of electron-donating groups to the aromatic rings causes the fluorescence of the compounds represented by general formulas (I1), (I2), (I3), or (I4) to be directed to longer wavelengths. Examples of electron-donating groups include alkyl groups; alkoxy groups such as methoxy groups; aryl groups such as phenyl groups, p-alkoxyphenyl groups, p-dialkylaminophenyl groups, and dialkoxyphenyl groups; and heteroaryl groups such as 2-thienyl groups and 2-furanyl groups. The number of carbon atoms in the alkyl group and the presence or absence of branching can be appropriately selected in consideration of various physical properties such as solubility and compatibility of the near-infrared fluorescent dye according to the present invention. a and R b , R c and R d , R hand R i , and R j and R k The substituents on the aromatic rings formed by each are C 1-6 Alkyl alkyl group, C 1-6 An alkoxy group, aryl group, or heteroaryl group is preferred, and a methyl group, ethyl group, methoxy group, phenyl group, p-methoxyphenyl group, p-ethoxyphenyl group, p-dimethylaminophenyl group, dimethoxyphenyl group, thienyl group, or furanyl group is more preferred. Because the BODIPY skeleton has high planarity, molecules tend to aggregate through π-π stacking. By introducing an aryl group or heteroaryl group with a bulky substituent into the BODIPY skeleton, molecular aggregation can be suppressed, and the luminescence quantum yield of the ink composition of the present invention can be increased.

[0030] In general formula (I1) or general formula (I2), R a and R b The aromatic ring formed by and R c and R d The aromatic ring formed by may be different from or the same as the one formed by R. In general formula (I3) or general formula (I4), h and R i The aromatic ring formed by and R j and R k The aromatic ring formed may be different from or the same as the one formed. The near-infrared fluorescent dye according to the present invention is easy to synthesize and tends to have a higher emission quantum yield, a and R b The aromatic ring and R that are formed c and R d The aromatic ring formed by, or R h and R i The aromatic ring and R that are formed j and R k The aromatic rings formed are preferably of the same type.

[0031] In general formula (I1) or general formula (I2), R e and R f These represent, independently of each other, a halogen atom or an oxygen atom. e and R fWhen the atom is a halogen atom, a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom is preferred, a fluorine atom or a chlorine atom is more preferred, and a fluorine atom is particularly preferred. e and R f Compounds in which the fluorine atom is present have a strong bond with the boron atom and exhibit high heat resistance.

[0032] In general formula (I1) or general formula (I2), R e and R f If R is an oxygen atom, e , R e The boron atom that bonds with R a , and R a The nitrogen atoms to which it is bonded may together form a ring, R f , R f The boron atom that bonds with R c , and R c The nitrogen atoms to which it is bonded may together form a ring. In other words, when a ring structure is formed, R e , R e The boron atom that bonds with R a , and R a The ring formed by the nitrogen atom to which it is bonded is R a and R b It condenses with the aromatic ring formed by R f , R f The boron atom that bonds with R c , and R c The ring formed by the nitrogen atom to which it is bonded is R c and R d It condenses with the aromatic ring that it forms. e Rings and R formed by the above f The ring formed by these is preferably a 6-membered ring.

[0033] In general formula (I1) or general formula (I2), R e If it is an oxygen atom and does not form a ring, then R e C is an oxygen atom having a substituent (an oxygen atom bonded to a substituent). The substituent may be C 1-20Examples include alkyl groups, aryl groups, heteroaryl groups, alkylcarbonyl groups, arylcarbonyl groups, or heteroarylcarbonyl groups. Similarly, in general formula (I1) or general formula (I2), R f If it is an oxygen atom and does not form a ring, then R f R is an oxygen atom having a substituent (an oxygen atom bonded to a substituent). The substituent is R. e The substituents are similar to those exemplified in the explanation. e and R f If both are oxygen atoms with substituents, R e The substituents and R f The substituents that it possesses may be of the same type or different types.

[0034] In general formula (I1) or general formula (I2), R e and R f If R is an oxygen atom, e , R f , and R e and R f The boron atoms bonded to it may together form a ring. For example, the ring structure may be R e and R f Structures in which the same aryl ring or heteroaryl ring is linked, R e and R f One example is a structure in which these groups are linked by alkylene groups.

[0035] In general formula (I3) or general formula (I4), R l , R m , R n , and R o These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. In the present invention and specification, "C" refers to a group that is alkoxy, aryl, or heteroaryl. 1-20 "Alkyl alkyl" refers to an alkyl group with 1 to 20 carbon atoms, and "C 1-20 The term "alkoxy group" refers to an alkoxy group having 1 to 20 carbon atoms. R l , R m , R n, or R o The halogen atom represented by is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom, more preferably a fluorine atom or a chlorine atom, and particularly preferably a fluorine atom. l , R m , R n , and R o Compounds in which the fluorine atom is present have a strong bond with the boron atom and exhibit high heat resistance. R l , R m , R n , or R o C represented by 1-20 The alkyl group may be linear, branched, or cyclic, and may be the same type of group as the alkyl group represented by the substituent mentioned above. R l , R m , R n , or R o C represented by 1-20 Examples of alkoxy groups include those similar to the alkoxy groups represented by the substituents mentioned above. R l , R m , R n , or R o The aryl group and heteroaryl group represented by can be the same as the aryl group and heteroaryl group represented by the substituents mentioned above. R l , R m , R n , or R o C represented by 1-20 Alkyl alkyl group, C 1-20 Alkoxy groups, aryl groups, and heteroaryl groups may have one or more hydrogen atoms substituted with substituents such as halogen atoms, alkyl groups, alkoxy groups, nitro groups, cyano groups, hydroxyl groups, amino groups, thiol groups, carboxyl groups, aldehyde groups, sulfonic acid groups, isocyanate groups, thioisocyanate groups, aryl groups, and heteroaryl groups.

[0036] Compounds represented by general formula (I3) or general formula (I4) include R l , R m , R n , and R oPreferably, the element is a halogen atom, an unsubstituted aryl group, or a substituted aryl group, and may be a fluorine atom, a chlorine atom, a bromine atom, an unsubstituted phenyl group, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group is preferred, and may be a fluorine atom, a chlorine atom, an unsubstituted phenyl group, or C 1-10 Alkyl or C 1-10 Phenyl groups substituted with alkoxy groups are more preferred, and fluorine atoms or unsubstituted phenyl groups are particularly preferred.

[0037] In general formula (I3) or general formula (I4), R p and R q These are, independently of each other, hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, aryl group, or heteroaryl group. p and R q The halogen atom represented by C 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, aryl group, and heteroaryl group are R of the general formula (I3) mentioned above. l , R m , R n , or R o Similar bases can be cited.

[0038] Compounds represented by general formula (I3) or general formula (I4) include R p and R q Compounds in which the group is a hydrogen atom or an aryl group are preferred, and unsubstituted phenyl groups or C 1-20 Alkyl or C 1-20 Compounds with phenyl groups substituted with alkoxy groups are preferred, as are unsubstituted phenyl groups or C 1-20 Compounds in which the phenyl group is substituted with an alkoxy group are more preferred, and unsubstituted phenyl groups or C 1-10 Compounds in which a phenyl group is substituted with an alkoxy group are particularly preferred.

[0039] In general formula (I1), R g R represents a hydrogen atom or an electron-withdrawing group. Also, in general formula (I3), Rr and R s These groups independently represent a hydrogen atom or an electron-withdrawing group. Examples of such electron-withdrawing groups include methyl halides such as trifluoromethyl; nitro; cyano; aryl; heteroaryl; alkynyl; alkenyl; substituents having a carbonyl group such as carboxyl, acyl, carbonyloxy, amide, and aldehyde; sulfoxide; sulfonyl; alkoxymethyl; and aminomethyl. Additionally, aryl and heteroaryl groups having these electron-withdrawing groups as substituents are also included. Among these, trifluoromethyl, nitro, cyano, phenyl, and sulfonyl groups are preferred because they can function as strong electron-withdrawing groups, thus extending the maximum fluorescence wavelength.

[0040] As near-infrared fluorescent dyes that can be used in the present invention, compounds having a borondipyrromethene skeleton represented by the following general formula (I1-0) or general formula (I2-0) are preferred because the maximum fluorescence wavelength is longer, and in particular compounds in which a pyrrole ring is fused with an aromatic ring or a heteroaromatic ring that satisfy the following (p2), (p3), (q2), or (q3) are preferred because the maximum fluorescence wavelength is even longer.

[0041] [ka]

[0042] In general formula (I1-0) or general formula (I2-0), R 1 , R 2 , and R 3 It satisfies one of the following conditions (p1) to (p3). (p1) Independently of each other, hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, an aryl group, or a heteroaryl group. (p2)R 1 and R 2 Both form an aromatic 5-membered ring or an aromatic 6-membered ring, R 3 is a hydrogen atom, halogen atom, C 1-20 Alkyl alkyl group, C 1-20Represents an alkoxy group, an aryl group, or a heteroaryl group, (p3)R 2 and R 3 Both form an aromatic 5-membered ring or an aromatic 6-membered ring, R 1 is a hydrogen atom, halogen atom, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. R 4 , R 5 , and R 6 It satisfies any of the following conditions (q1) to (q3). (q1) Independently of each other, hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, an aryl group, or a heteroaryl group. (q2)R 4 and R 5 Both form an aromatic 5-membered ring or an aromatic 6-membered ring, R 6 is a hydrogen atom, halogen atom, C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, an aryl group, or a heteroaryl group, (q3)R 5 and R 6 Both form an aromatic 5-membered ring or an aromatic 6-membered ring, R 4 is a hydrogen atom, halogen atom, C 1-20 Alkyl alkyl group, C 1-20 Alkoxy group, aryl group, or heteroaryl group It represents a le group.

[0043] The halogen atoms in (p1)~(p3) or (q1)~(q3) above, C 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, aryl group, and heteroaryl group are, respectively, R a and R b Examples of substituents that may be present in the aromatic ring formed by the compound include groups similar to those exemplified above.

[0044] In the above (p2)~(p3) or (q2)~(q3), R 1 and R2 , R 4 and R 5 , R 2 and R 3 , and R 5 and R 6 The aromatic five-membered ring or aromatic six-membered ring formed by these components together is preferably a structure represented by any of the following general formulas (C-1) to (C-9), and more preferably a structure represented by any of the following general formulas (C-1), (C-2), or (C-9). In the following general formulas (C-1) to (C-9), the parts marked with an asterisk are the parts that bond with the borondipyrromethene skeleton in general formula (I1-0) or general formula (I2-0).

[0045] [ka]

[0046] In the general formulas (C-1) to (C-8), Y 1 ~Y 8 These elements independently represent a sulfur atom, an oxygen atom, a nitrogen atom, or a phosphorus atom. 1 ~Y 8 Preferably, these atoms are sulfur atoms, oxygen atoms, or nitrogen atoms, and more preferably, sulfur atoms or oxygen atoms, independently of each other.

[0047] In the general formulas (C-1) to (C-9), R 11 ~R 22 These are hydrogen atoms, or R, that are independent of each other. a and R b R represents a group similar to the substituents exemplified above that may be present in the aromatic ring formed by the compound. 11 ~R 22Preferably, each of these groups is independently a hydrogen atom, an unsubstituted aryl group, a substituted aryl group, an unsubstituted heteroaryl group, or a substituted heteroaryl group; more preferably, a hydrogen atom, an (unsubstituted) phenyl group, a p-methoxyphenyl group, a p-ethoxyphenyl group, a p-dimethylaminophenyl group, a dimethoxyphenyl group, a thienyl group, or a furanyl group; and even more preferably, a hydrogen atom, an (unsubstituted) phenyl group, or a p-methoxyphenyl group. It is particularly preferable that the compound is substituted with at least one of the aforementioned unsubstituted aryl groups, substituted aryl groups, unsubstituted heteroaryl groups, or substituted heteroaryl groups, in order to enhance electron-donating properties and to suppress aggregation of the BODIPY skeleton by the bulky substituents.

[0048] As for compounds of general formula (I1-0) or general formula (I2-0), R 1 and R 4 , R 2 and R 5 , and R 3 and R 6 These may be different from each other, but it is preferable that they be of the same type. That is, R 1 , R 2 , and R 3 If the above (p1) is satisfied, R 4 , R 5 , and R 6 It is preferable that the above (q1) is satisfied, and R 1 , R 2 , and R 3 If the above (p2) is satisfied, R 4 , R 5 , and R 6 It is preferable that the above (q2) is satisfied, R 1 , R 2 , and R 3 If the above (p3) is satisfied, R 4 , R 5 , and R 6 It is preferable that the above (q3) is satisfied.

[0049] As for compounds of general formula (I1-0) or general formula (I2-0), R1 and R 2 They form a ring, R 4 and R 5 R forms a ring, or 2 and R 3 They form a ring, R 5 and R 6 It is preferable that the rings form a ring. That is, R 1 , R 2 , and R 3 The above (p2) or (p3) is satisfied, R 4 , R 5 , and R 6 A compound satisfying (q2) or (q3) is preferred. This is because the condensation of an aromatic ring or heteroaromatic ring with the borondipyrrometene skeleton results in a longer wavelength for maximum fluorescence.

[0050] In general formula (I1-0) or general formula (I2-0), R 7 and R 8 R represents a halogen atom or an oxygen atom. 7 and R 8 If it is an oxygen atom, R 7 , R 7 A boron atom bonded to it, a nitrogen atom bonded to the boron atom, R 1 , and R 1 The carbon atoms bonded to it may together form a ring, R 8 , R 8 A boron atom bonded to it, a nitrogen atom bonded to the boron atom, R 4 , and R 4 The carbon atoms bonded to it may together form a ring. That is, R 7 and boron atoms and R 1 The ring formed by the etc., and R 8 and boron atoms and R 4 The rings formed by these structures all condense with the borondipyrromethene skeleton. 7 and boron atoms and R 1 The ring formed by the etc., and R 8 and boron atoms and R 4 The ring formed by these is preferably a 6-membered ring.

[0051] In general formula (I1-0) or general formula (I2-0), R 7 If it is an oxygen atom and does not form a ring, then R 7 C is an oxygen atom having a substituent (an oxygen atom bonded to a substituent). The substituent may be C 1-20 Examples include alkyl groups, aryl groups, or heteroaryl groups. Similarly, in general formula (I1-0) or general formula (I2-0), R 8 If it is an oxygen atom and does not form a ring, then R 8 C is an oxygen atom having a substituent (an oxygen atom bonded to a substituent). The substituent may be C 1-20 Examples include alkyl groups, aryl groups, or heteroaryl groups. 7 and R 8 If both are oxygen atoms with substituents, R 7 The substituents and R 8 The substituents that it possesses may be of the same type or different types.

[0052] In general formula (I1-0), R 9 R represents a hydrogen atom or an electron-withdrawing group. As an electron-withdrawing group, R g Similar groups to those listed above can be cited. Among these, fluoroalkyl groups, nitro groups, cyano groups, aryl groups, and sulfonyl groups are preferred from the viewpoint of extending the maximum fluorescence wavelength, as they can function as strong electron-withdrawing groups, and trifluoromethyl groups, nitro groups, cyano groups, phenyl groups, and sulfonyl groups are more preferred.

[0053] The near-infrared fluorescent dye according to the present invention is a compound represented by general formula (I1-0) or general formula (I2-0), R 1 and R 2 Both are rings represented by the above general formula (C-1), R 11 and R 12 One of them is a hydrogen atom, and the other has 1 to 3 of its hydrogen atoms as halogen atoms, C 1-20 Alkyl alkyl group, or C 1-20 A ring is formed which is a phenyl group, thienyl group, or furanyl group, which may be substituted with an alkoxy group, R4 and R 5 Both are R 1 and R 2 It forms a ring of the same kind as the ring formed by R 3 and R 6 is a hydrogen atom, and R 7 and R 8 A compound in which the atom is a halogen atom; R 1 and R 2 Both are rings represented by the above general formula (C-2), R 13 and R 14 One of them is a hydrogen atom, and the other has 1 to 3 of its hydrogen atoms as halogen atoms, C 1-20 Alkyl alkyl group, or C 1-20 A ring is formed which is a phenyl group, thienyl group, or furanyl group, which may be substituted with an alkoxy group, R 4 and R 5 Both are R 1 and R 2 It forms a ring of the same kind as the ring formed by R 3 and R 6 is a hydrogen atom, and R 7 and R 8 A compound in which the atom is a halogen atom; R 2 and R 3 Both are rings represented by the above general formula (C-1), R 11 and R 12 One of them is a hydrogen atom, and the other has 1 to 3 of its hydrogen atoms as halogen atoms, C 1-20 Alkyl alkyl group, or C 1-20 A ring is formed which is a phenyl group, thienyl group, or furanyl group, which may be substituted with an alkoxy group, R 5 and R 6 Both are R 2 and R 3 It forms a ring of the same kind as the ring formed by R 1 and R 4 is a hydrogen atom, and R 7 and R 8 A compound in which the atom is a halogen atom; R 2 and R 3Both are rings represented by the following general formula (C-2), R 13 and R 14 One of them is a hydrogen atom, and the other has 1 to 3 of its hydrogen atoms as halogen atoms, C 1-20 Alkyl alkyl group, or C 1-20 A ring is formed which is a phenyl group, thienyl group, or furanyl group, which may be substituted with an alkoxy group, R 5 and R 6 Both are R 2 and R 3 It forms a ring of the same kind as the ring formed by R 1 and R 4 is a hydrogen atom, and R 7 and R 8 A compound in which the atom is a halogen atom; R 2 and R 3 Both are rings represented by the following general formula (C-9), R 19 ~R 22 One of the hydrogen atoms is a halogen atom, and C 1-20 Alkyl alkyl group, or C 1-20 A phenyl group, thienyl group, or furanyl group which may be substituted with an alkoxy group, and the remaining three atoms form a ring with hydrogen atoms, R 5 and R 6 Both are R 2 and R 3 It forms a ring of the same kind as the ring formed by R 1 and R 4 hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, or C 1-20 A phenyl group, thienyl group, or furanyl group which may be substituted with an alkoxy group, R 7 and R 8 A compound in which the atom is a halogen atom is preferred. If these compounds are represented by the general formula (I1-0), then R 9 Compounds in which the group is a trifluoromethyl group, a cyano group, a nitro group, or a phenyl group are more preferred, and compounds in which the group is a trifluoromethyl group or a phenyl group are particularly preferred.

[0054] Preferred compounds for the near-infrared fluorescent dye according to the present invention include the following general compounds (I1-1), (I1-2), (I1-3), (I2-1), (I2-2), and (I2-3). Among the following general compounds (I1-1), etc., R 1 , R 3 , R 4 , and R 6 ~R 8 The above is synonymous, ED represents an electron-donating group, EW represents an electron-withdrawing group, and Z 1 ~Z 4 Each ring independently represents a five-membered or six-membered aryl group, or a five-membered or six-membered heteroaryl group.

[0055] [ka]

[0056] For the general formula (I1-1), compounds represented by the general formulas (I1-1-1) to (I1-1-6) are preferred; for the general formula (I1-2), compounds represented by the general formulas (I1-2-1) to (I1-2-12) are preferred; for the general formula (I2-1), compounds represented by the general formulas (I2-1-1) to (I2-1-6) are preferred; and for the general formula (I2-2), compounds represented by the general formulas (I2-2-1) to (I2-2-12) are preferred.

[0057] [ka]

[0058] [ka]

[0059] [ka]

[0060] [ka]

[0061] [ka]

[0062] [ka]

[0063] In the general formulas (I1-1-1)~(I1-1-6), (I1-2-1)~(I1-2-4), (I1-2-7)~(I1-2-10), (I2-1-1)~(I2-1-6), (I2-2-1)~(I2-2-4), and (I2-2-7)~(I2-2-10), Y 11 and Y 12 These represent, independently of each other, an oxygen atom or a sulfur atom, and Y 21 and Y 22 These represent a carbon atom or a nitrogen atom independently of each other. Compounds represented by general formula (I1-1-1), etc., include Y 11 and Y 12 Preferably, the atoms are of the same type, Y 21 and Y 22 It is preferable that these atoms are of the same type.

[0064] In general formulas (I1-1-1)~(I1-1-6), (I1-2-1)~(I1-2-12), Q 11 R represents a hydrogen atom or an electron-withdrawing group. As an electron-withdrawing group, R g Groups similar to those listed above can be cited. Compounds represented by general formula (I1-1-1), etc., are Q 11 Compounds in which the group is a trifluoromethyl group, a cyano group, a nitro group, or an optionally substituted phenyl group are preferred, and compounds in which the group is a trifluoromethyl group or an optionally substituted phenyl group are more preferred.

[0065] In the general formulas (I1-1-1)~(I1-1-2), (I1-2-1)~(I1-2-2), (I1-2-6), (I2-1-1)~(I2-1-2), and (I2-2-1)~(I2-2-2), (I2-2-6), X is a halogen atom, C, and X are independent of each other. 1-20 This represents an alkoxy group, an aryloxy group, or an acyloxy group.

[0066] X represents C 1-20 The alkyl group portion of the alkoxy group may be linear, branched, or cyclic (aliphatic ring group). Examples of such alkoxy groups include methoxy, ethoxy, propyloxy, isopropyloxy, n-butyloxy, isobutyloxy, t-butyloxy, pentyloxy, isoamyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, undecyloxy, and dodecyloxy groups. Examples of aryloxy groups represented by X include phenyloxy group, naphthyloxy group, indenyloxy group, and biphenyloxy group. Examples of the acyloxy group represented by X include alkylcarbonyloxy groups such as methylcarbonyloxy group (acetoxy group), ethylcarbonyloxy group, propylcarbonyloxy group, isopropylcarbonyloxy group, n-butylcarbonyloxy group, isobutylcarbonyloxy group, t-butylcarbonyloxy group, pentylcarbonyloxy group, isoamylcarbonyloxy group, hexylcarbonyloxy group, heptylcarbonyloxy group, octylcarbonyloxy group, nonylcarbonyloxy group, decylcarbonyloxy group, undecylcarbonyloxy group, and dodecylcarbonyloxy group; and arylcarbonyloxy groups such as phenylcarbonyloxy group (benzoyloxy group), naphthylcarbonyloxy group, indenylcarbonyloxy group, and biphenylcarbonyloxy group.

[0067] Of the compounds represented by any of the general formulas (I1-1-1)~(I1-1-2), (I1-2-1)~(I1-2-2), (I1-2-6), (I2-1-1)~(I2-1-2), (I2-2-1)~(I2-2-2), and (I2-2-6), compounds in which X is all a halogen atom are preferred, and compounds in which X is all a fluorine atom are particularly preferred.

[0068] In the general formulas (I1-1-3)~(I1-1-4), (I1-2-7), (I1-2-9), (I1-2-11), (I2-1-3)~(I2-1-4), (I2-2-7), (I2-2-9), and (I2-2-11), m1 represents either 0 or 1.

[0069] In the general formulas (I1-1-5)~(I1-1-6), (I1-2-3)~(I1-2-6), (I1-2-8), (I1-2-10)~(I1-2-12), (I2-1-5)~(I2-1-6), (I2-2-3)~(I1-2-6), (I2-2-8), and (I2-2-10)~(I2-2-12), P 11 ~P 14 and P 17 These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an amino group, a monoalkylamino group, or a dialkylamino group. 11 ~P 14 C in 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, monoalkylamino group, or dialkylamino group are, respectively, the R g The same groups as those listed in (p1)~(p3) and (q1)~(q3) can be cited. 11 ~P 14 and P 17 C 1-20 Alkyl alkyl group, C 1-20 It is preferable that the group is an alkoxy group, an (unsubstituted) phenyl group, a p-methoxyphenyl group, a p-ethoxyphenyl group, a p-dimethylaminophenyl group, a dimethoxyphenyl group, a thienyl group, or a furanyl group.

[0070] In the general formulas (I1-1-5)~(I1-1-6), (I1-2-3)~(I1-2-6), (I1-2-8), (I1-2-10)~(I1-2-12), (I2-1-5)~(I2-1-6), (I2-2-3)~(I1-2-6), (I2-2-8), and (I2-2-10)~(I2-2-12), n11~n14 and n17 independently represent integers from 0 to 3. In one numerator, P 11 If there are multiple instances of (i.e., n11 is 2 or 3), multiple P 11 These groups may be of the same type or different types. 12 ~P 14 and P 17 The same applies to this matter.

[0071] In the general formulas (I1-1-1)~(I1-1-6), (I1-2-1)~(I1-2-4), (I1-2-6)~(I1-2-12), (I2-1-1)~(I2-1-6), (I2-2-1)~(I2-2-4), and (I2-2-6)~(I2-2-12), A 11 ~A 14 These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 A phenyl group having 1 to 3 substituents selected from the group consisting of alkoxy groups, amino groups, monoalkylamino groups, and dialkylamino groups, or a halogen atom, C 1-20 Alkyl alkyl group, C 1-20 This represents a heteroaryl group which may have 1 to 3 substituents selected from the group consisting of alkoxy groups, amino groups, monoalkylamino groups, and dialkylamino groups. The R in the general formula (I3) above represents the heteroaryl group. l , R m , R n , or R o Similar groups are mentioned, with thienyl or furanyl groups being preferred. C in the substituent that the phenyl group or heteroaryl group may have. 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, monoalkylamino group, or dialkylamino group are, respectively, the R gThe same groups as those listed in (p1)~(p3) and (q1)~(q3) can be listed. A 11 ~A 14 These include an unsubstituted phenyl group and one or two carbon atoms. 1-20 A phenyl group having an alkoxy group as a substituent, or a heteroaryl group, is preferred, as is an unsubstituted phenyl group or one carbon atom. 1-20 A phenyl group having an alkoxy group as a substituent is more preferable, as is an unsubstituted phenyl group or a single carbon atom. 1-10 A phenyl group having an alkoxy group as a substituent is more preferable, as is an unsubstituted phenyl group or a single carbon atom. 1-6 A phenyl group having an alkoxy group as a substituent is even more preferred. Also, compounds represented by general formula (I1-1-1), etc., are A 11 ~A 14 Preferably, all of these are of the same type.

[0072] The near-infrared fluorescent dye according to the present invention is preferably a compound represented by any of the following general formulas (1-1) to (1-37), (2-1) to (2-7), (3-1) to (3-37), (4-1) to (4-7), or (5-1) to (5-2). A compound represented by any of the following general formulas (1-1) to (1-12), (1-25) to (1-31), (2-1) to (2-7), or (3-25) to (3-31) is more preferably a compound represented by any of the following general formulas (1-1), (1-3), (1-4), (1-6), (1-25), (1-27), (2-1), (3-1), (3-3), (3-4), (3-6), (3-25), (3-27), or (4-1).

[0073] [ka]

[0074] [ka]

[0075] [ka]

[0076] [ka]

[0077] [ka]

[0078] [ka]

[0079] [ka]

[0080] [ka]

[0081] [ka]

[0082] [ka]

[0083] [ka]

[0084] In general formulas (1-1) to (1-37), (2-1) to (2-7), (3-1) to (3-37), (4-1) to (4-7), (5-1) to (5-2), P 1 ~P 4 and P 18 These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20This represents an alkoxy group, an amino group, a monoalkylamino group, or a dialkylamino group. 1 ~P 4 C in 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, monoalkylamino group, or dialkylamino group are, respectively, the R g The same groups as those listed in (p1)~(p3) and (q1)~(q3) can be cited. 1 ~P 4 and P 18 C 1-20 Alkyl alkyl group, C 1-20 It is preferable that the group is an alkoxy group, an (unsubstituted) phenyl group, a p-methoxyphenyl group, a p-ethoxyphenyl group, a p-dimethylaminophenyl group, a dimethoxyphenyl group, a thienyl group, or a furanyl group.

[0085] In the general formulas (1-1)~(1-37), (2-1)~(2-7), (3-1)~(3-37), (4-1)~(4-7), and (5-1)~(5-2), n1~n4 and n18 represent integers from 0 to 3, independently of each other. In one numerator, P 1 If there are multiple instances of (i.e., when n1 is 2 or 3), multiple P 1 These may all be of the same type or different types. 2 ~P 4 and P 18 The same applies to this matter.

[0086] In general formulas (1-1) to (1-37), (2-1) to (2-7), and (5-1), Q represents a trifluoromethyl group, a cyano group, a nitro group, or an optionally substituted phenyl group, preferably a trifluoromethyl group or an optionally substituted phenyl group, and more preferably a trifluoromethyl group or an unsubstituted phenyl group. Optional substituents on the phenyl group include halogen atoms and C 1-20 Alkyl alkyl group, C 1-20 Examples include alkoxy groups, amino groups, monoalkylamino groups, and dialkylamino groups.

[0087] In general formulas (1-1) to (1-31) and (3-1) to (3-31), X is the same as in general formula (1-1-1), etc. In compounds represented by general formula (1-1), etc., X is preferably a halogen atom, and particularly preferably a fluorine atom.

[0088] In general formulas (1-32) to (1-34) and (3-32) to (3-34), m2 is either 0 or 1. For compounds represented by general formula (1-32), etc., it is preferable that m2 is 1.

[0089] Compounds represented by general formulas (1-1) to (1-37), (2-1) to (2-7), and (5-1) include P 1 ~P 4 and P 18 They are independent of each other, C 1-20 Alkyl alkyl group, C 1-20 Compounds are preferred in which the group is an alkoxy group, an (unsubstituted) phenyl group, a p-methoxyphenyl group, a p-ethoxyphenyl group, a p-dimethylaminophenyl group, a dimethoxyphenyl group, a thienyl group, or a furanyl group, n1 to n4 and n18 are independently 0 to 2, and Q is a trifluoromethyl group or a phenyl group. Similarly, compounds represented by the general formulas (3-1) to (3-37), (4-1) to (4-7), and (5-2) include P 1 ~P 4 and P 18 They are independent of each other, C 1-20 Alkyl alkyl group, C 1-20 Compounds are preferred that are alkoxy groups, (unsubstituted) phenyl groups, p-methoxyphenyl groups, p-ethoxyphenyl groups, p-dimethylaminophenyl groups, dimethoxyphenyl groups, thienyl groups, or furanyl groups, and n1 to n4 and n18 are independently 0 to 2.

[0090] As the near-infrared fluorescent dye according to the present invention, compounds represented by any of the following general formulas (I3-1) to (I3-6), or compounds represented by any of the general formulas (I4-1) to (I4-6), are also preferred because their maximum fluorescence wavelength is longer.

[0091] [ka]

[0092] [ka]

[0093] In general formulas (I3-1) to (I3-6) and general formulas (I4-1) to (I4-6), R 23 , R 24 , R 25 , and R 26 These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, aryl group, or heteroaryl group. 23 , R 24 , R 25 , or R 26 The halogen atom represented by C 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, aryl group, and heteroaryl group are R of the general formula (I3) mentioned above. l , R m , R n , or R o Similar groups can be cited. Compounds represented by any of the general formulas (I3-1) to (I3-6) or any of the general formulas (I4-1) to (I4-6) are considered to have high thermal stability, and R 23 , R 24 , R 25 , and R 26 Compounds in which the atom is a halogen atom, an unsubstituted aryl group, or a substituted aryl group are preferred, specifically a fluorine atom, a chlorine atom, a bromine atom, an unsubstituted phenyl group, or C 1-20 Alkyl or C 1-20 Compounds that are phenyl groups substituted with alkoxy groups are preferred, and may contain a fluorine atom, a chlorine atom, an unsubstituted phenyl group, or C 1-10 Alkyl or C 1-10 Compounds in which the phenyl group is substituted with an alkoxy group are more preferred, as they yield compounds that combine high luminescence efficiency and thermal stability. Therefore, compounds in which the phenyl group is fluorine or unsubstituted are particularly preferred.

[0094] In general formulas (I3-1) to (I3-6) and general formulas (I4-1) to (I4-6), R 27 and R 28 These are, independently of each other, hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, aryl group, or heteroaryl group. 27 or R 28 The halogen atom represented by C 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, aryl group, and heteroaryl group are R of the general formula (I3) mentioned above. p or R q Similar groups can be cited. Compounds represented by any of the general formulas (I3-1) to (I3-6) or any of the general formulas (I4-1) to (I4-6) include R 27 and R 28 Compounds in which the group is a hydrogen atom or an aryl group are preferred, as compounds with high luminescence efficiency can be obtained. 1-20 Alkyl or C 1-20 Compounds consisting of phenyl groups substituted with alkoxy groups are preferred, and also include hydrogen atoms, unsubstituted phenyl groups, or linear or branched C atoms. 1-20 Compounds in which the phenyl group is substituted with an alkoxy group are more preferable, as compounds with high luminescence efficiency can be obtained. 1-10 Compounds in which a phenyl group is substituted with an alkoxy group are particularly preferred.

[0095] In general formulas (I3-1) to (I3-6), R 29 and R 30 These independently represent a hydrogen atom or an electron-withdrawing group. 29 or R 30 The electron-withdrawing group represented by is R in the general formula (I3) above. r or R sSimilar groups can be cited. Compounds represented by any of the general formulas (I3-1) to (I3-6) can be obtained as compounds with longer fluorescence wavelengths and high luminescence efficiency, R 29 and R 30 However, compounds that are fluoroalkyl groups, nitro groups, cyano groups, or aryl groups that can function as strong electron-withdrawing groups are preferred, and compounds that are trifluoromethyl groups, nitro groups, cyano groups, or phenyl groups which may have substituents are more preferred, as compounds with high luminescence efficiency can be obtained, and therefore compounds with trifluoromethyl groups or cyano groups are more preferred.

[0096] In general formula (I3-1) and general formula (I4-1), Y 9 and Y 10 These represent a sulfur atom, an oxygen atom, a nitrogen atom, or a phosphorus atom independently of each other. Compounds represented by general formula (I3-1) or general formula (I4-1) are obtained because they have high luminescence efficiency. 9 and Y 10 However, compounds in which each atom is independently a sulfur atom, an oxygen atom, or a nitrogen atom are preferred, and compounds in which each atom is independently a sulfur atom or an oxygen atom are more preferred, as compounds that combine high luminescence efficiency and thermal stability can be obtained. Therefore, compounds in which both atoms are sulfur atoms or both atoms are oxygen atoms are even more preferred.

[0097] In general formulas (I3-3) to (I3-6) and general formulas (I4-3) to (I4-6), X 1 and X 2 These represent a nitrogen atom or a phosphorus atom independently of each other. Compounds represented by general formulas (I3-3) to (I3-6) or general formulas (I4-3) to (I4-6) include X 1 and X 2 However, compounds that are both nitrogen atoms or phosphorus atoms are preferred because they yield compounds with high luminescence efficiency, and compounds that are both nitrogen atoms are more preferred because they yield compounds that combine high luminescence efficiency and thermal stability.

[0098] In general formula (I3-1) and general formula (I4-1), R 31 and R 32The following conditions (p4) or (p5) are met: (p4) Independently of each other, hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (p5)R 31 and R 32 Both form an aromatic five-membered ring or an aromatic six-membered ring, which may have substituents. R 33 and R 34 The following conditions (q4) or (q5) are met. (q4) Independently of each other, hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 Represents an alkoxy group, an aryl group, or a heteroaryl group, (q5)R 33 and R 34 Both form an aromatic five-membered ring or an aromatic six-membered ring, which may have substituents.

[0099] In general formulas (I3-2) to (I3-6) and general formulas (I4-2) to (I4-6), R 35 , R 36 , R 37 , and R 38 It satisfies one of the following conditions (p6) to (p9). (p6) Independently of each other, hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (p7)R 35 and R 36 Both form an aromatic five-membered ring or an aromatic six-membered ring which may have substituents, R 37 and R 38 These are independent of each other: hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (p8)R 36 and R 37Both form an aromatic five-membered ring or an aromatic six-membered ring which may have substituents, R 35 and R 38 These are independent of each other: hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (p9)R 37 and R 38 Both form an aromatic five-membered ring or an aromatic six-membered ring which may have substituents, R 35 and R 36 These are independent of each other: hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. R 39 , R 40 , R 41 , and R 42 It satisfies any of the following conditions (q6) to (q9). (q6) Independently of each other, hydrogen atoms, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (q7)R 39 and R 40 Both form an aromatic five-membered ring or an aromatic six-membered ring which may have substituents, R 41 and R 42 These are independent of each other: hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (q8)R 40 and R 41 Both form an aromatic five-membered ring or an aromatic six-membered ring which may have substituents, R 39 and R 42 These are independent of each other: hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group. (q9)R41 and R 42 Both form an aromatic five-membered ring or an aromatic six-membered ring which may have substituents, R 39 and R 40 These are independent of each other: hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an aryl group, or a heteroaryl group.

[0100] The halogen atoms in (p4), (p6)~(p9) and (q4), (q6)~(q9), C 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, aryl group, and heteroaryl group are, respectively, R a and R b The substituents that may be present in the aromatic ring formed are similar to those exemplified above.

[0101] In the above (p5), (p7)~(p9), (q5), (q7)~(q9), R 31 and R 32 , R 33 and R 34 , R 35 and R 36 , R 36 and R 37 , R 37 and R 38 , R 39 and R 40 , R 40 and R 41 , and R 41 and R 42 However, the aromatic five-membered ring or aromatic six-membered ring formed together is preferably a structure represented by any of the general formulas (C-1) to (C-9), and the structure represented by general formula (C-9) is more preferred because it yields a compound with high thermal stability.

[0102] The compound represented by (I3-1) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; R 29 and R 30 Both are trifluoromethyl, nitro, cyano, or phenyl groups; Y 9 and Y 10 Both are sulfur atoms or oxygen atoms; R 31 and R 32 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 31 and R 32 They both form a phenyl group which may have substituents; R 33 and R 34 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 33 and R 34 Compounds that form a phenyl group which may both have substituents are preferred because they have high luminescence efficiency.

[0103] The compound represented by (I3-2) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; R 29 and R 30 Both are trifluoromethyl, nitro, cyano, or phenyl groups; R 35 , R 36 , R 37 , and R 38 These are hydrogen atoms or C, independently of each other.1-20 Is it an alkyl group, or R 35 and R 36 Both may form a phenyl group having substituents R 37 and R 38 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 36 and R 37 Both may form a phenyl group having substituents R 35 and R 38 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 37 and R 38 Both may form a phenyl group having substituents R 35 and R 36 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group; R 39 , R 40 , R 41 , and R 42 These are hydrogen atoms or C, independently of each other. 1-20 R is an alkyl group. 39 and R 40 Both may form a phenyl group having substituents R 41 and R 42 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 40 and R 41 Both may form a phenyl group having substituents R 39 and R 42 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 41 and R 42 Both may form a phenyl group having substituents R 39 and R 40 These are hydrogen atoms or C, independently of each other. 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0104] The compound represented by (I3-3) above is R 23 , R 24 , R 25 , and R26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; R 29 and R 30 Both are trifluoromethyl, nitro, cyano, or phenyl groups; X 1 and X 2 Both are nitrogen atoms; R 36 , R 37 , and R 38 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 36 and R 37 Both may form a phenyl group having substituents R 38 is a hydrogen atom or C 1-20 It is an alkyl group, or R 37 and R 38 Both may form a phenyl group having substituents R 36 is a hydrogen atom or C 1-20 It is an alkyl group; R 40 , R 41 , and R 42 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 40 and R 41 Both may form a phenyl group having substituents R 42 is a hydrogen atom or C 1-20 It is an alkyl group, or R 41 and R 42 Both may form a phenyl group having substituents R 40 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0105] The compound represented by (I3-4) above is R 23 , R 24 , R25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; R 29 and R 30 Both are trifluoromethyl, nitro, cyano, or phenyl groups; X 1 and X 2 Both are nitrogen atoms; R 35 , R 36 , and R 37 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 35 and R 36 Both may form a phenyl group having substituents R 37 is a hydrogen atom or C 1-20 It is an alkyl group, or R 36 and R 37 Both may form a phenyl group having substituents R 35 is a hydrogen atom or C 1-20 It is an alkyl group; R 39 , R 40 , and R 41 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 39 and R 40 Both may form a phenyl group having substituents R 41 is a hydrogen atom or C 1-20 It is an alkyl group, or R 40 and R 41 Both may form a phenyl group having substituents R 39 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0106] The compounds represented by (I3-5) above include R 23 , R24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; R 29 and R 30 Both are trifluoromethyl, nitro, cyano, or phenyl groups; X 1 and X 2 Both are nitrogen atoms; R 35 , R 36 , and R 38 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 35 and R 36 Both may form a phenyl group having substituents R 38 is a hydrogen atom or C 1-20 It is an alkyl group; R 39 , R 40 , and R 42 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 39 and R 40 Both may form a phenyl group having substituents R 42 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0107] The compound represented by (I3-6) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20an alkyl group or a C 1-20 phenyl group substituted with an alkoxy group; R 29 and R 30 are both a trifluoromethyl group, a nitro group, a cyano group, or a phenyl group; X 1 and X 2 are both nitrogen atoms; R 35 , R 37 , and R 38 are independently of each other a hydrogen atom or a C 1-20 alkyl group, or R 37 and R 38 together form a phenyl group which may have substituents and R 35 is a hydrogen atom or a C 1-20 alkyl group; R 39 , R 41 , and R 42 are independently of each other a hydrogen atom or a C 1-20 alkyl group, or R 41 and R 42 together form a phenyl group which may have substituents and R 39 is a hydrogen atom or a C 1-20 alkyl group; The compound is preferred because of its high luminous efficiency.

[0108] Examples of the compound represented by (I4-1) include those in which R 23 , R 24 , R 25 , and R 26 are all a halogen atom, an unsubstituted phenyl group, or a C 1-10 alkyl group or a phenyl group substituted with a C 1-10 alkoxy group; R 27 and R 28 are both a hydrogen atom, an unsubstituted phenyl group, or a C 1-20 alkyl group or a phenyl group substituted with a C 1-20 alkoxy group; Y 9 and Y 10 are both a sulfur atom or an oxygen atom; R 31 and R 32 are independently of each other a hydrogen atom or a C 1-20 alkyl group, or R 31 and R32 They both form a phenyl group which may have substituents; R 33 and R 34 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 33 and R 34 Compounds that form a phenyl group which may both have substituents are preferred because they have high luminescence efficiency.

[0109] The compound represented by (I4-2) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; R 35 , R 36 , R 37 , and R 38 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 35 and R 36 Both may form a phenyl group having substituents R 37 and R 38 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 36 and R 37 Both may form a phenyl group having substituents R 35 and R 38 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 37 and R 38 Both may form a phenyl group having substituents R 35 and R 36 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group; R 39 , R 40 , R41 and R 42 are each independently a hydrogen atom or a C 1-20 alkyl group, or R 39 and R 40 together form a phenyl group which may have substituents, and R 41 and R 42 are each independently a hydrogen atom or a C 1-20 alkyl group, or R 40 and R 41 together form a phenyl group which may have substituents, and R 39 and R 42 are each independently a hydrogen atom or a C 1-20 alkyl group, or R 41 and R 42 together form a phenyl group which may have substituents, and R 39 and R 42 are each independently a hydrogen atom or a C 1-20 alkyl group; The compound is preferred because of its high luminous efficiency.

[0110] Examples of the compound represented by (I4-3) include cases where R 23 , R 24 , R 25 , and R 26 are all halogen atoms, unsubstituted phenyl groups, or phenyl groups substituted with a C 1-10 alkyl group or a C 1-10 alkoxy group; R 27 and R 28 are both hydrogen atoms, unsubstituted phenyl groups, or phenyl groups substituted with a C 1-20 alkyl group or a C 1-20 alkoxy group; X 1 and X 2 are both nitrogen atoms; R 36 , R 37 , and R 38 are each independently a hydrogen atom or a C 1-20 alkyl group, or R 36 and R 37 together form a phenyl group which may have substituents, and R 38 is a hydrogen atom or a C 1-20 alkyl group, or R37 and R 38 Both may form a phenyl group having substituents R 36 is a hydrogen atom or C 1-20 It is an alkyl group; R 40 , R 41 , and R 42 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 40 and R 41 Both may form a phenyl group having substituents R 42 is a hydrogen atom or C 1-20 It is an alkyl group, or R 41 and R 42 Both may form a phenyl group having substituents R 40 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0111] The compound represented by (I4-4) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; X 1 and X 2 Both are nitrogen atoms; R 35 , R 36 , and R 37 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 35 and R 36 Both may form a phenyl group having substituents R 37 is a hydrogen atom or C 1-20 It is an alkyl group, or R 36 and R 37 Both may form a phenyl group having substituents R35 is a hydrogen atom or C 1-20 It is an alkyl group; R 39 , R 40 , and R 41 These are hydrogen atoms or C, independently of each other. 1-20 Is it an alkyl group, or R 39 and R 40 Both may form a phenyl group having substituents R 41 is a hydrogen atom or C 1-20 It is an alkyl group, or R 40 and R 41 Both may form a phenyl group having substituents R 39 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are more preferred because they have higher luminescence efficiency.

[0112] The compound represented by (I4-5) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; X 1 and X 2 Both are nitrogen atoms; R 35 , R 36 , and R 38 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 35 and R 36 Both may form a phenyl group having substituents R 38 is a hydrogen atom or C 1-20 It is an alkyl group; R 39 , R 40 , and R 42 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 39 and R40 Both may form a phenyl group having substituents R 42 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0113] The compound represented by (I4-6) above is R 23 , R 24 , R 25 , and R 26 Both are halogen atoms, unsubstituted phenyl groups, or C 1-10 Alkyl or C 1-10 A phenyl group substituted with an alkoxy group; R 27 and R 28 Both are hydrogen atoms, unsubstituted phenyl groups, or C 1-20 Alkyl or C 1-20 A phenyl group substituted with an alkoxy group; X 1 and X 2 Both are nitrogen atoms; R 35 , R 37 , and R 38 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 37 and R 38 Both may form a phenyl group having substituents R 35 is a hydrogen atom or C 1-20 It is an alkyl group; R 39 , R 41 , and R 42 These are hydrogen atoms or C, independently of each other. 1-20 It is an alkyl group, or R 41 and R 42 Both may form a phenyl group having substituents R 39 is a hydrogen atom or C 1-20 Compounds that are alkyl groups are preferred because they have high luminescence efficiency.

[0114] The compound represented by any of (I3-1) to (I3-6) above is preferably a compound represented by any of the following general formulas (I3-7) to (I3-9), and the compound represented by any of (I4-1) to (I4-6) above is preferably a compound represented by any of the following general formulas (I4-7) to (I4-9).

[0115] [ka]

[0116] In general formulas (I3-7) and (I4-7), Y 23 and Y 24 These represent, independently of each other, a carbon atom or a nitrogen atom. In general formulas (I3-7), etc., Y 23 and Y 24 It is preferable that these atoms are of the same type. In general formulas (I3-8) and (I4-8), Y 13 and Y 14 These represent, independently of each other, an oxygen atom or a sulfur atom. In general formulas (I3-8), etc., Y 13 and Y 14 It is preferable that these atoms are of the same type. In general formulas (I3-9) and (I4-9), Y 25 and Y 26 These represent, independently of each other, a carbon atom or a nitrogen atom. In general formulas (I3-9), etc., Y 25 and Y 26 It is preferable that these atoms are of the same type. In general formulas (I3-7) to (I3-9), R 47 and R 48 These groups independently represent a hydrogen atom or an electron-withdrawing group, and since they increase fluorescence intensity, trifluoromethyl, cyano, nitro, sulfonyl, or phenyl groups are preferred, with trifluoromethyl or cyano groups being particularly preferred. In general formula (I3-7), R 47 and R 48 It is preferable that these are the same type of group.

[0117] In general formulas (I3-7) to (I3-9) and (I4-7) to (I4-9), R 43, R 44 , R 45 , and R 46 R represents a halogen atom or an aryl group which may have a substituent. a and R b The substituents that may be present in the aromatic ring formed are similar to those exemplified above. Furthermore, examples of substituents that the aryl group may have include C 1-6 Alkyl alkyl group, C 1-6 Examples include alkoxy groups, aryl groups, or heteroaryl groups. In general formulas (I3-7) to (I3-9) and (I4-7) to (I4-9), R 43 ~R 46 These may each be different groups, but it is preferable that they are all of the same type. Compounds represented by any of the general formulas (I3-7)~(I3-9) and (I4-7)~(I4-9) include R 43 ~R 46 However, compounds in which all are halogen atoms of the same type, or phenyl groups which may all have substituents of the same type, are preferred, compounds in which all are fluorine atoms or unsubstituted phenyl groups are more preferred, and compounds in which all are fluorine atoms are particularly preferred.

[0118] In general formulas (I3-7) to (I3-9) and (I4-7) to (I4-9), P 15 ~P 16 These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an amino group, a monoalkylamino group, or a dialkylamino group. 15 ~P 16 C in 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, monoalkylamino group, or dialkylamino group are, respectively, the R g The same groups listed in (p1)~(p3) and (q1)~(q3) can be listed. 15 ~P 16 C 1-20 Alkyl alkyl group, C 1-20A preferred group is an alkoxy group, an (unsubstituted) phenyl group, a p-methoxyphenyl group, a p-ethoxyphenyl group, a p-dimethylaminophenyl group, a dimethoxyphenyl group, a thienyl group, or a furanyl group.

[0119] In the general formulas (I3-7)~(I3-9) and (I4-7)~(I4-9), n15~n16 represent integers from 0 to 3, independently of each other. In one numerator, P 15 If there are multiple instances of (i.e., n15 is 2 or 3), multiple P 15 The groups may be of the same type or different types. 16 The same applies to this matter.

[0120] In general formulas (I3-7) to (I3-9) and (I4-7) to (I4-9), A 15 ~A 16 These are, independently of each other, hydrogen atoms, halogen atoms, and C 1-20 Alkyl alkyl group, C 1-20 This represents a phenyl group which may have 1 to 3 substituents selected from the group consisting of alkoxy groups, amino groups, monoalkylamino groups, and dialkylamino groups. 1-20 Alkyl alkyl group, C 1-20 The alkoxy group, monoalkylamino group, or dialkylamino group are, respectively, the R g The same groups listed in (p1)~(p3) and (q1)~(q3) can be listed. 15 ~A 16 Examples include an unsubstituted phenyl group and one or two C12s. 1-20 A phenyl group having an alkoxy group as a substituent is preferred, as is an unsubstituted phenyl group or a single carbon atom. 1-20 A phenyl group having an alkoxy group as a substituent is more preferable, as is an unsubstituted phenyl group or a single carbon atom. 1-10 A phenyl group having an alkoxy group as a substituent is even more preferred. Also, in compounds represented by general formula (I3-7), A 15 ~A 16 Preferably, all of them are of the same type of functional group.

[0121] Compounds represented by any of the above formulas (I3-1) to (I3-6) and (I4-1) to (I4-6) include compounds represented by any of the following general formulas (6-1) to (6-12) and (7-1) to (7-12), with compounds represented by general formulas (6-4), (6-5), (6-7), (6-8), (7-4), (7-5), (7-7), and (7-8) being preferred, and compounds represented by general formulas (6-4), (6-5), (6-7), and (6-8) being more preferred. In the formulas, Ph represents a phenyl group.

[0122] In general formulas (6-1) to (6-12), (7-1) to (7-12), P 5 ~P 8 These are, independently of each other, halogen atoms, C 1-20 Alkyl alkyl group, C 1-20 This represents an alkoxy group, an amino group, a monoalkylamino group, or a dialkylamino group. 5 ~P 8 C in 1-20 Alkyl alkyl group, C 1-20 Examples of alkoxy groups, monoalkylamino groups, or dialkylamino groups are, respectively, R g This is similar to the groups listed in (p1)~(p3) and (q1)~(q3). P 5 ~P 8 C 1-20 Alkyl alkyl group, C 1-20 Preferably, it is an alkoxy group, an (unsubstituted) phenyl group, a p-methoxyphenyl group, a p-ethoxyphenyl group, a p-dimethylaminophenyl group, a dimethoxyphenyl group, a thienyl group, or a furanyl group, C 1-10 Alkyl alkyl group or C 1-10 An alkoxy group is more preferable.

[0123] In the general formulas (6-1)~(6-12) and (7-1)~(7-12), n5~n8 represent integers from 0 to 3, independently of each other. In one numerator, P 5 If there are multiple instances of (i.e., n5 is 2 or 3), multiple P 5 These may all be of the same type or different types. 6 ~P 8The same applies to this matter.

[0124] [ka]

[0125] [ka]

[0126] [ka]

[0127] [ka]

[0128] Compounds represented by general formulas (6-1) to (6-12) and (7-1) to (7-12) include P 5 ~P 8 C 1-20 Alkyl alkyl group or C 1-20 A compound with an alkoxy group, where n5 to n8 are independently 0 to 2, is preferred, P 5 and P 6 C 1-20 It is an alkyl group, and n5 and n6 are independently 0 to 2, P 7 and P 8 C 1-20 A compound having an alkoxy group, where n7 and n8 are independently 0 to 1, is more preferable, P 5 and P 6 C 1-20 It is an alkyl group, and n5 and n6 are independently 1 to 2, P 7 and P 8 C 1-20 Compounds that are alkoxy groups and have n7 and n8 at 1 are even more preferred.

[0129] Compounds represented by general formulas (6-1) to (6-12) specifically include those represented by the following formulas (6-1-1) to (6-12-1). "λ" is the peak wavelength of the absorption spectrum of each compound, and "Em" is the peak wavelength of the fluorescence spectrum.

[0130] [ka]

[0131] [ka]

[0132] [Polymerizable compound] The polymerizable compound contained in the ink composition of the present invention can be either a monofunctional polymerizable compound or a polyfunctional polymerizable compound. Here, the polymerizable compound is preferably a compound having an ethylenic double bond. Examples of monofunctional polymerizable compounds include monofunctional (meth)acrylates having linear or cyclic aliphatic groups, monofunctional (meth)acrylates having alkylene oxy groups, monofunctional (meth)acrylates having aromatic hydrocarbon groups, monofunctional (meth)acrylates having functional groups such as hydroxyl groups and phosphate groups, compounds having heterocyclic structures, and monovinyl ether compounds.

[0133] Examples of monofunctional (meth)acrylates having a linear or cyclic aliphatic group include isoamyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, decyl (meth)acrylate, isomiristyl (meth)acrylate, isostearyl (meth)acrylate, and other monofunctional (meth)acrylates having a linear aliphatic group; Examples include (meth)acrylates having cyclic aliphatic groups such as cyclohexyl (meth)acrylate, 4-t-butylcyclohexyl (meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, adamantyl (meth)acrylate, cyclohexanedimethanol mono(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, trimethylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, t-butylcyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, and dicyclopentenyloxyethyl (meth)acrylate. By including a (meth)acrylate having a cyclic aliphatic group, the viscosity of the ink composition of the present invention can be easily adjusted to a viscosity range suitable for molding by inkjet printing. Furthermore, the shrinkage of the cured product formed from the ink composition of the present invention is reduced, resulting in improved adhesion and other properties.

[0134] Examples of monofunctional (meth)acrylates having an alkylene oxy group include methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxyethoxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2-ethylhexyldiglycol (meth)acrylate, diethylene glycol mono(meth)acrylate, diethylene glycol monobutyl ether (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, and methoxypropylene glycol (meth)acrylate.

[0135] Examples of monofunctional (meth)acrylates having aromatic hydrocarbon groups include 2-phenoxyethyl (meth)acrylate and benzyl (meth)acrylate. 2-phenoxyethyl acrylate is preferred from the viewpoint of inkjet ejectability, adhesion of the resulting coating film, and flexibility (stretch resistance) at low temperatures.

[0136] Examples of (meth)acrylates having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-ethylhexyl diglycol (meth)acrylate, diethylene glycol mono(meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 1,4-cyclohexanedimethanol monoacrylate, and 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol. When the ink composition of the present invention contains a (meth)acrylate having a hydroxyl group, the moisture resistance, heat resistance, and adhesion to the substrate of the cured product formed from the ink composition of the present invention tend to be improved.

[0137] Examples of (meth)acrylates having a phosphate group include alkylene (meth)acrylates such as methylene (meth)acrylate phosphate, ethylene (meth)acrylate phosphate, propylene (meth)acrylate phosphate, and tetramethylene (meth)acrylate phosphate, as well as phosphate esters of polyethylene glycol monoacrylate and phosphate esters of polypropylene glycol monomethacrylate. When the ink composition of the present invention contains a (meth)acrylate having a phosphate group, the curability is improved, and the properties such as adhesion between the cured product formed from the ink composition of the present invention and the substrate tend to be improved.

[0138] Examples of compounds having a heterocyclic structure include N-vinylcaprolactam, N-vinylpyrrolidone, N-vinylformamide, N-vinylmethyloxazolidinone (also known as 5-methyl-3-vinyl-2-oxazolidinone), (meth)acryloylmorpholine, N-(meth)acryloyloxyethylhexahydrophthalimide, tetrahydrofurfuryl(meth)acrylate, and cyclic trimethylolpropaneformal(meth)acrylate.

[0139] Examples of monovinyl ether compounds include ethylene glycol monovinyl ether, triethylene glycol monovinyl ether, hydroxyethyl monovinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, hydroxynonyl monovinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl vinyl ether, dodecyl vinyl ether, diethylene glycol monovinyl ether, phenyl glycidyl ether, butyl glycidyl ether, and 2-ethylhexyl glycidyl ether.

[0140] The monofunctional polymerizable compound described above is preferably a compound that has polymerizable unsaturated double bonds and is liquid at 25°C, with a molecular weight of 60 to 2000, and more preferably 100 to 1000. Furthermore, the viscosity of the monofunctional polymerizable compound at 25°C is preferably 1000 mPa·s or less, more preferably 300 mPa·s or less, and even more preferably 50 mPa·s or less. Such a viscosity is preferably 1 mPa·s or more, and more preferably 3 mPa·s or more.

[0141] In this specification, (meth)acrylates having a hydroxyl group and a cyclic skeleton are classified as (meth)acrylates having a hydroxyl group, and (meth)acrylates having a phosphate group and a cyclic skeleton are classified as (meth)acrylates having a phosphate group. Furthermore, monomers having two or more (meth)acrylate groups shall be classified as (meth)acrylates having hydroxyl groups or (meth)acrylates having phosphate groups if they have one or more hydroxyl groups or phosphate groups, regardless of the presence or absence of a cyclic skeleton, and shall be classified as compounds having two or more (meth)acrylate groups if they do not have either hydroxyl groups or phosphate groups. In other words, (meth)acrylates having a cyclic skeleton include mono(meth)acrylates that have a cyclic skeleton but do not have either a hydroxyl group or a phosphate group.

[0142] Examples of polyfunctional polymerizable compounds include compounds having two or more (meth)acrylate groups, and polymerizable compounds having two or more polymerizable groups that are different from those compounds having two or more (meth)acrylate groups (hereinafter referred to as "other polyfunctional polymerizable compounds"). Here, a polymerizable group means a group having a polymerizable unsaturated double bond.

[0143] Examples of compounds having two or more (meth)acrylate groups include ethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, and 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate. Glycol di(meth)acrylates such as acrylate, tricyclodecanedimethanol di(meth)acrylate, ethoxylated (2) neopentyl glycol di(meth)acrylate [compound obtained by di(meth)acrylate of a 2-mol adduct of neopentyl glycol ethylene oxide], propoxylated (2) neopentyl glycol di(meth)acrylate [compound obtained by di(meth)acrylate of a 2-mol adduct of neopentyl glycol propylene oxide], and hydroxypivalic acid neopentyl glycol di(meth)acrylate;

[0144] Diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, bis(4-acryloxypolyethoxyphenyl)propane, and other alkylene glycol di(meth)acrylates; Di(meth)acrylate of tris(2-hydroxyethyl) isocyanurate; Dimethylol tricyclodecane di(meth)acrylate, caprolactone-modified hydroxypivalate neopentyl glycol di(meth)acrylate; Bisphenol A di(meth)acrylate, propylene oxide-modified bisphenol A type di(meth)acrylate, ethylene oxide-modified bisphenol A type di(meth)acrylate, bisphenol F di(meth)acrylate, propylene oxide-modified bisphenol F type di(meth)acrylate, ethylene oxide-modified bisphenol F type di(meth)acrylate; Trifunctional (meth)acrylates such as pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane ethylene oxide modified tri(meth)acrylate, trimethylolpropane propylene oxide modified tri(meth)acrylate, tetramethylolmethane tri(meth)acrylate, modified glycerin tri(meth)acrylate, glycerin propylene oxide adduct tri(meth)acrylate, and glycerin ethylene oxide adduct tri(meth)acrylate; Tetrafunctional (meth)acrylates such as pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and tetramethylolmethane tetra(meth)acrylate; Hexafunctional (meth)acrylates such as dipentaerythritol hexa(meth)acrylate and caprolactone-modified dipentaerythritol hexa(meth)acrylate; These are some examples.

[0145] Furthermore, urethane (meth)acrylate and amino (meth)acrylate can be used as compounds having two or more (meth)acrylate groups. Urethane (meth)acrylate and amino (meth)acrylate may be monomers, oligomers, or polymers. In this specification, "monomer" refers to a compound with a molecular weight (or weight-average molecular weight, if a molecular weight distribution exists) of 1000 or less. The molecular weight (or weight-average molecular weight, if a molecular weight distribution exists) of monomers is between 50 and 1000. "Oligomer" generally refers to a polymer having a finite number of constituent units (generally 5 to 100) based on monomers, with a weight-average molecular weight exceeding 1000 but less than 30000. "Polymer" refers to a polymer with a weight-average molecular weight of 30000 or more. The weight-average molecular weight is measured by gel permeation chromatography (GPC) and is calculated as a value equivalent to standard polystyrene.

[0146] Examples of urethane (meth)acrylates include aliphatic urethane (meth)acrylates and aromatic urethane (meth)acrylates. The weight-average molecular weight of the urethane (meth)acrylate is preferably 1,000 to 30,000, and more preferably 2,000 to 20,000. Commercially available urethane (meth)acrylates can also be used, for example, U-2PPA, U-4HA, U-6HA, U-6LPA, U-15HA, U-324A, UA-122P, UA5201, UA-512 etc. from Shin Nakamura Chemical Industry Co., Ltd.; and CN965NS, CN964A85, CN964, CN959, CN962, CN963J85, CN965, CN965NS, CN982 from ARKEMA (Sartomer). Examples include B88, CN981, CN983, CN991, CN996, CN9002, CN9906NS, CN9007, CN9009, CN9010, CN9011, CN9178, CN9788, CN9893; and Daicel Ornex products such as EBECRYL230, EBECRYL270, EBECRYL8402, EBECRYL8804, EBECRYL8807, EBECRYL9270, KRM8191, etc.

[0147] Amino(meth)acrylate is an amine-modified (meth)acrylate having an amino group. The number-average molecular weight of amino(meth)acrylate is preferably 500 to 20000, more preferably 600 to 10000, and even more preferably 800 to 5000. Commercially available amino(meth)acrylates can also be used, such as EBECRYL7100 and EBECRYL80 from Daicel Ornex, and CN551 from ARKEMA (Sartomer). When the ink composition of the present invention contains a compound having two or more (meth)acrylate groups, the curability of the ink composition of the present invention is improved, and the flexibility and adhesion to the substrate of the cured product formed from the ink composition of the present invention are easily improved.

[0148] Other polyfunctional polymerizable compounds include those with the following general formula (α): CH2=CR 5 -COO-R 6-O-CH=CH-R 7 ...(α) (In the formula, R 5 R represents a hydrogen atom or a methyl group. 6 R represents an organic residue with 2 to 20 carbon atoms. 7 (This represents a hydrogen atom or an organic residue with 1 to 11 carbon atoms.) A monomer represented by (hereinafter simply referred to as "monomer (α)"), The following general formula (β), CH2=C(CH2OCH2CH=CH2)-COO-R 7 ...(β) (In the formula, R 7 The above definition applies. Examples include monomers represented by (hereinafter simply referred to as "monomer (β)"), divinyl ether compounds, trivinyl ether compounds, etc. In general formula (α), R 6 Examples of C2-C20 organic residues represented by include linear, branched, or cyclic alkylene groups with C2-C20, C2-C20 alkylene groups having oxygen atoms in their structure via ether and / or ester bonds, and C6-C11 aromatic groups in which hydrogen atoms bonded to carbon atoms constituting the ring may be substituted with other substituents. Preferably, C2-C6 alkylene groups and C2-C9 alkylene groups having oxygen atoms in their structure via ether bonds are used. In general formulas (α) and (β), R 7 Examples of C1-C11 organic residues represented by include C1-C10 linear, branched, or cyclic alkyl groups, C6-C11 aromatic groups in which hydrogen atoms bonded to carbon atoms constituting the ring may be substituted with other substituents, with C1-C2 alkyl groups and C6-C8 aromatic groups being preferred.

[0149] Specific examples of monomer (α) include (meth)acrylate 2-vinyloxyethyl, (meth)acrylate 3-vinyloxypropyl, (meth)acrylate 1-methyl-2-vinyloxyethyl, (meth)acrylate 2-vinyloxypropyl, (meth)acrylate 4-vinyloxybutyl, (meth)acrylate 1-methyl-3-vinyloxypropyl, (meth)acrylate 1-vinyloxymethylpropyl, (meth)acrylate 2-methyl-3-vinyloxypropyl, (meth)acrylate 3-methyl-3-vinyl Xypropyl, 1,1-dimethyl-2-vinyloxyethyl (meth)acrylate, 3-vinyloxybutyl (meth)acrylate, 1-methyl-2-vinyloxypropyl (meth)acrylate, 2-vinyloxybutyl (meth)acrylate, 4-vinyloxycyclohexyl (meth)acrylate, 5-vinyloxypentyl (meth)acrylate, 6-vinyloxyhexyl (meth)acrylate, 4-vinyloxymethylcyclohexylmethyl (meth)acrylate, p-vinyloxymethylphenyl (meth)acrylate Methyl, 2-(vinyloxyethoxy)ethyl (meth)acrylate, 2-(vinyloxyisopropoxy)ethyl (meth)acrylate, 2-(vinyloxyethoxy)propyl (meth)acrylate, 2-(vinyloxyethoxy)isopropyl (meth)acrylate, 2-(vinyloxyisopropoxy)propyl (meth)acrylate, 2-(vinyloxyisopropoxy)isopropyl (meth)acrylate, 2-(vinyloxyethoxyethoxy)ethyl (meth)acrylate Examples include 2-(vinyloxyethoxy)ethyl methacrylate, 2-(vinyloxyethoxyisopropoxy)propyl methacrylate, 2-(vinyloxyethoxyethoxy)isopropyl methacrylate, 2-(vinyloxyethoxyisopropoxy)isopropyl methacrylate, 2-(vinyloxyethoxyethoxyethoxy)ethyl methacrylate, polyethylene glycol monovinyl ether methacrylate, and polypropylene glycol monovinyl ether methacrylate. As monomer (1), 2-(2-vinyloxyethoxy)ethyl methacrylate is preferred, and 2-(2-vinyloxyethoxy)ethyl acrylate is more preferred, from the viewpoint of low viscosity, high flash point, and excellent curability.

[0150] Specific examples of monomer (β) include methyl allyloxymethylacrylate and ethyl allyloxymethylacrylate.

[0151] Examples of divinyl ether compounds or trivinyl ether compounds include ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, trimethylolpropane trivinyl ether, and the like.

[0152] The polymerizable compound constituting the ink composition of the present invention preferably has the function of dissolving the above-mentioned near-infrared fluorescent dye. In other words, it is extremely preferable that the above-mentioned near-infrared fluorescent dye exists in a dissolved state in the polymerizable compound constituting the ink composition of the present invention. Preferred polymerizable compounds having the function of dissolving the above-mentioned near-infrared fluorescent dyes are monofunctional (meth)acrylates, such as compounds having a heterocyclic structure like tetrahydrofurfuryl (meth)acrylate; monofunctional (meth)acrylates having an alkylene oxy group like (ethoxyethoxy)ethyl (meth)acrylate; monofunctional (meth)acrylates having an aromatic hydrocarbon group like 2-phenoxyethyl (meth)acrylate and benzyl (meth)acrylate; and methyl allyloxymethylacrylate. Among these, tetrahydrofurfuryl methacrylate, 2-(2-ethoxyethoxy)ethyl acrylate, 2-phenoxyethyl acrylate, and benzyl acrylate are more preferred.

[0153] Furthermore, if the near-infrared fluorescent dye does not have an aryl group or a heteroaryl group as a substituent bonded to its boron atom, it is preferable that the polymerizable compound has a structure that does not have a vinyl group directly bonded to the nitrogen atom, from the viewpoint of not interfering with the excitation fluorescence of the near-infrared fluorescent dye by irradiation with near-infrared light and suppressing a decrease in fluorescence intensity. In other words, if the near-infrared fluorescent dye contained in the ink does not have an aryl group or heteroaryl group as a substituent bonded to its boron atom, it is preferable that the ink composition of the present invention does not contain polymerizable compounds having a vinyl group directly bonded to a nitrogen atom, such as N-vinylcaprolactam, N-vinylpyrrolidone, N-vinylformamide, and N-vinylmethyloxazolidinone.

[0154] The ink composition of the present invention may or may not contain a solvent. Examples of such solvents include ethers such as 3-methoxy-1-butanol, 3-methoxy-3-methylbutanol, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, anisole, and phenethole. Esters such as methyl lactate, ethyl lactate, butyl lactate, methyl 2-hydroxyisobutanoate, ethyl acetate, butyl acetate, pentyl formate, isopentyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, methyl pyruvate, methyl acetoacetate, and γ-butyrolactone; Ether esters such as ethyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 2-methoxypropionate, ethyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, ethyl 2-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate; Glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dipropyl ether, and diethylene glycol dibutyl ether; Glycol ether esters such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, and dipropylene glycol methyl ether acetate; Alcohols such as methanol, ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, and propylene glycol; Ketones such as acetone, 2-butanone, 2-heptanone, 4-methyl-2-pentanone, cyclopentanone, and cyclohexanone; Amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone; Aliphatic hydrocarbons such as hexane and octane; Examples include aromatic hydrocarbons such as benzene, toluene, and xylene.

[0155] The ink composition of the present invention preferably does not contain a solvent. In this specification, "solvent-free" means that the solvent content in the ink composition of the present invention is 1% by mass or less. The solvent content is preferably 0.5% by mass or less, and more preferably 0.1% by mass or less. The ink composition of the present invention, even without containing a solvent, contains a polymerizable compound that has the function of dissolving near-infrared fluorescent dyes, thereby allowing the near-infrared fluorescent dyes to exist in a dissolved state and achieving the effects of the present invention described above. Therefore, the manufacturing process of the ink composition of the present invention can be simplified, and safety in handling can be improved. Furthermore, it can be coated by inkjet method, and annealing treatment is unnecessary when curing. In addition, the ink composition of the present invention has high fluorescence emission intensity even after curing, and the decrease in such fluorescence emission intensity can be suppressed and maintained over a long period of time.

[0156] The ink composition of the present invention may further contain a photopolymerization initiator, and it is preferable that it contains a photopolymerization initiator. Examples of photopolymerization initiators include acylphosphine compounds such as 2-methylbenzoyl diphenylphosphine oxide, bis(2,6-dichlorobenzoyl)phenylphosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, (2,4,6-trimethylbenzoyl)diphenylphosphine oxide, 2,6-dimethoxybenzoyl diphenylphosphine oxide, 2,6-dichlorobenzoyl diphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide; Phosphinic acid ester compounds such as (2,4,6-trimethylbenzoyl)phenylphosphinate methyl, (2,4,6-trimethylbenzoyl)phenylphosphinate ethyl, (3-benzoyl-2,4,6-trimethylbenzoyl)phenylphosphinate methyl, (3-benzoyl-2,4,6-trimethylbenzoyl)phenylphosphinate ethyl, and pivaloylphenylphosphinate isopropyl; Benzoin isobutyl ether, 2,4-diethylthioxanthone [also known as 2,4-diethylthioxanthene-9-one], 2-isopropylthioxanthone, methylbenzoyl formate, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 1-hydroxycyclohexylphenyl ketone, benzoin ethyl ether, benzyldimethyl ketal, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methyl Examples include propan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, benzophenone, 4-phenylbenzophenone, isophthalphenone, 4-benzoyl-4'-methyldiphenyl sulfide, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-(4-morpholinophenyl)-butan-1-one), 1-{4-[(4-benzoylphenyl)sulfanyl]phenyl}-2-methyl-2-[(4-methylphenyl)sulfonyl]propan-1-one, etc. The photopolymerization initiator may contain one type alone or two or more types. When the ink composition of the present invention contains a photopolymerization initiator, its content is preferably 0.1 to 20% by mass, and more preferably 2 to 12% by mass, relative to the total ink composition of the present invention. When the content of the photopolymerization initiator is within the above range, the curability and storage stability of the ink composition of the present invention tend to be good, and the performance of the formed cured product tends to improve.

[0157] If the ink composition of the present invention contains a photopolymerization initiator, the ink composition of the present invention may further contain a sensitizer. Examples of sensitizers include trimethylamine, methyldimethanolamine, triethanolamine, p-diethylaminoacetophenone, ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, N,N-dimethylbenzylamine, 4,4'-bis(diethylamino)benzophenone, anthracene-9,10-diethyl ether, and 9,10-bis(n-heptanoyloxy)anthracene. If the ink composition of the present invention contains a sensitizer, its content is preferably 0.1 to 10% by mass, and more preferably 0.5 to 8% by mass, relative to the total mass of the ink composition of the present invention. When the sensitizer content is within the above range, the curability of the ink composition of the present invention is good, and the performance of the formed cured product tends to improve.

[0158] The ink composition of the present invention may further contain surfactants from the viewpoint of adjusting surface tension and improving handling and discharge stability. Various anionic, nonionic, and cationic surfactants can be appropriately selected as the surfactant. Specifically, examples include anionic surfactants such as dialkyl sulfosuccinates, alkylnaphthalene sulfonates, and fatty acid salts; nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols, and polyoxyethylene-polyoxypropylene block copolymers; cationic surfactants such as alkylamine salts and quaternary ammonium salts; silicone-based surfactants having silicone chains, polymer chains such as silicone chains and poly(meth)acrylate chains, and silicone-based surfactants having polyether chains as side chains or terminals and a polysiloxane structure in the main chain; and preferably hydrophobic organic fluoro compounds such as fluorine-based surfactants having perfluoroalkyl chains, oily fluorine-based compounds (e.g., fluorine oils), and solid fluorine compound resins (e.g., tetrafluoroethylene resins). These can be obtained as commercially available products such as the "MegaFac®" series from DIC Corporation, the "Futergent®" series from Neos Corporation, the "BYK®" series from BYK Corporation, the "TEGO® Rad" series from Evonik Corporation, the "DISPARLON® OX" series from Kusumoto Chemical Co., Ltd., and "Polyflow No. 7," "Florence AC-300," and "Florence AC-303" from Kyoeisha Chemical Co., Ltd. If the ink composition of the present invention contains a surfactant, the amount is preferably 0.05 to 2% by mass, and more preferably 0.1 to 1% by mass, relative to the total ink composition of the present invention, from the viewpoint of ensuring discharge stability and setting the surface tension within a desired range.

[0159] In addition to the components described above, the ink composition of the present invention may further optionally contain polymerization inhibitors such as hydroquinone, di-t-butylhydroquinone, p-methoxyphenol, benzoquinone, butylhydroxytoluene, nitrosamine salts, hindered amine compounds, and 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO). If a polymerization inhibitor is included, the amount is preferably in the range of 0.01 to 2% by mass relative to the total amount of the ink composition of the present invention.

[0160] The ink composition of the present invention may further contain additives such as ultraviolet absorbers, antioxidants, leveling agents, fade inhibitors, and conductive salts. Furthermore, from the viewpoint of further improving adhesion to substrates such as plastic substrates, it may also contain non-reactive resins such as acrylic resins, epoxy resins, terpene phenolic resins, and rosin esters.

[0161] The ink composition of the present invention can be manufactured by supplying the aforementioned near-infrared fluorescent dye, polymerizable compound, and optionally other components such as photopolymerization initiators and various additives, using a conventional disperser such as a bead mill or stirrer, and then stirring and mixing them. When using a bead mill, glass beads or zirconia beads can be used as the beads. In addition to bead mills, various known and conventional dispersers can be used, such as ultrasonic homogenizers, high-pressure homogenizers, paint shakers, ball mills, roll mills, sand mills, sand grinders, Dyno mills, Dispermats, SC mills, and nanomizers. In the ink composition obtained according to the present invention, the dissolution of the near-infrared fluorescent dye can be confirmed by measuring the difference between the absorption spectrum obtained when a small amount of the near-infrared fluorescent dye is dissolved in a highly soluble solvent and the absorption spectrum obtained in the ink composition.

[0162] Examples of active energy rays used to cure this ink composition include visible light, ultraviolet light, infrared light, microwaves, EUV, semiconductor laser light, and excimer lasers (KrF, ArF). Examples of light sources such as ultraviolet light include metal halide lamps, xenon lamps, carbon arc lamps, chemical lamps, low-pressure mercury lamps, high-pressure mercury lamps, UV-LED lamps, and laser diodes (LDs).

[0163] The ink composition of the present invention is also suitably applicable as an inkjet ink. That is, the present invention encompasses the active energy ray curable ink composition of the present invention, which is formed by an inkjet method. In inkjet printing, any of the conventionally known methods can be used as the ink ejection method, such as a method that ejects droplets using the vibration of a piezoelectric element (a recording method using an inkjet head that forms ink droplets by the mechanical deformation of an electrostrictive element), a method that utilizes thermal energy, a method that uses an actuator that utilizes electrostatic force, or a method that uses a continuous-jet type charged control head. The viscosity of the ink composition of the present invention at 25°C is preferably in the range of 3 to 30 mPa·s, and more preferably in the range of 5 to 25 mPa·s. Furthermore, the surface tension of the ink composition of the present invention is preferably in the range of 15 to 45 mN / m. When the viscosity and surface tension of the ink composition of the present invention at 25°C are within the above ranges, it is preferable from the viewpoint of improving the handling of the ink composition of the present invention and the inkjet ejection stability when printing by inkjet method. The ink composition of the present invention can be easily adjusted to the viscosity within the above range even without containing a solvent.

[0164] The present invention also includes cured products of the ink composition of the present invention. Such cured products can be formed by a manufacturing method that includes a step of curing the ink composition of the present invention by irradiating it with active energy rays. For example, the ink composition of the present invention can be dispensed onto a substrate, which is a recording medium, using an inkjet recording device, and cured by irradiation with active energy rays to produce a printed material. More specifically, a recorded material (printed material) can be produced by an inkjet recording method that includes the steps of adhering the ink composition of the present invention to a recording medium (substrate) and curing the ink composition of the present invention adhering to the recording medium by irradiating it with active energy rays. The step of depositing the ink composition of the present invention onto a substrate can be performed using a known inkjet recording device. When ejecting the ink composition of the present invention, it is preferable that the viscosity of the ink composition at 25°C be 3 to 30 mPa·s, and more preferably 5 to 20 mPa·s, from the viewpoint of improving continuous inkjet ejection performance and ejection stability. It is preferable to keep the temperature of the composition as constant as possible during ejection. In the process of irradiating with active energy rays, for example, the irradiation energy of light using a UV-LED is 50-1000 mJ / cm². 2 Preferably, it is within the range of 200-800 mJ / cm². 2 A range is more preferable. The ink composition of the present invention preferably has a pencil hardness of 3H or higher when cured, and while possessing such hardness, it exhibits excellent adhesion to various substrates.

[0165] Examples of records (printed materials) to which the ink composition of the present invention can be applied include records (printed materials) used for traceability and anti-counterfeiting purposes of food and various industrial products. There are no particular limitations on the substrate that can be used as a recording medium to which the ink composition of the present invention can be applied. Examples include resins and paper, and these may be flat substrates such as films, or substrates having curved surfaces or irregular, uneven shapes.

[0166] Although the ink composition of the present invention has been described above, the present invention is not limited to the configuration of the embodiments described above. For example, the ink composition of the present invention may have additional configurations of any other choice in the configuration of the above embodiments, or may be replaced with any configuration that produces a similar effect. [Examples]

[0167] The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples. The compounds used in these examples are shown below.

[0168] <Examples of near-infrared fluorescent dye synthesis> Manufacturing Example 1: Synthesis of Near-Infrared Fluorescent Dye A (1) Under an argon stream, 2.99 g (19.7 mmol) of 4-methoxyphenylboronic acid was placed in a 500 mL three-necked flask and dissolved in 120 mL of toluene. Then, 100 mg of [1,1'-bis(diphenylphosphino)-ferrocene]palladium(II) dichloride-dichloromethane complex (1:1), 30 mL of ethanol, 3.46 g (19.8 mmol) of 5-bromo-2-furaldehyde, and 20 mL of 2 mol / L aqueous sodium carbonate solution were added, and the mixture was stirred at 80°C for 14 hours. The organic phase was separated from the reaction mixture, washed with water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The resulting crude product was purified by flash silica gel chromatography (eluent: hexane / ethyl acetate = 19 / 1 → 4 / 1 (volume ratio)) to obtain 5-(4-methoxyphenyl)-furan-2-carboaldehyde (hereinafter referred to as compound (a-1)) as a pale yellow liquid (yield 3.39 g, yield 84.8%). (2) Next, in a 1 L three-necked flask, under a stream of argon, 3.39 g (16.8 mmol) of compound (a-1) and 8.65 g (67.0 mmol) of ethyl azido were dissolved in 300 mL of ethanol. To the resulting solution, 22.8 g (67.0 mmol) of 20% by mass sodium ethoxide ethanol solution was slowly added dropwise in an ice bath, and after the addition was complete, the mixture was stirred for 2 hours. The reaction mixture was then diluted with saturated ammonium chloride aqueous solution to adjust the pH to weakly acidic, filtered, and the recovered solid was washed with water and then dried to obtain 2-azido-3-[5-(4-methoxyphenyl)-furan-2-yl]-ethyl acrylate (hereinafter referred to as compound (a-2)) as a yellow solid (yield 3.31 g, yield 63.1%).

[0169] (3) 3.31 g (10.6 mmol) of compound (a-2) and 60 mL of toluene were placed in a 200 mL round-bottom flask and dissolved, and the mixture was stirred under reflux for 1.5 hours. The resulting solution was concentrated under reduced pressure, and the crude product was recrystallized with a mixture of hexane and ethyl acetate, filtered, and dried to obtain 2-(4-methoxyphenyl)-4H-flu[3.2-b]pyrrole-5-carboxylate ethyl (hereinafter referred to as compound (a-3)) as brown crystals (yield 2.32 g, yield 76.8%). (4) Next, 1.90 g (6.66 mmol) of compound (a-3), 60 mL of ethanol, and an aqueous solution of 3.90 g (97.5 mmol) of sodium hydroxide dissolved in 30 mL of water were added to a 300 mL flask, and the mixture was stirred under reflux for 1 hour. The resulting solution was allowed to cool to 25°C, adjusted to acidity by adding 6 mol / L hydrochloric acid, filtered, and the recovered solid was washed with water and then dried to obtain 2-(4-methoxyphenyl)-4H-flu[3.2-b]pyrrole-5-carboxylic acid (hereinafter referred to as compound (a-4)) as a gray solid (yield 1.56 g, yield 91%).

[0170] (5) 327 mg (5.52 mmol) of compound (a-4) and 16.5 mL of trifluoroacetic acid were placed in a 200 mL three-necked flask and stirred at 45°C. After compound (a-4) dissolved, the mixture was stirred for a further 15 minutes until the foaming subsided. 3.3 mL of anhydrous trifluoroacetic acid was added to this solution and the mixture was reacted at 80°C for 1 hour. The reaction mixture was neutralized with saturated sodium bicarbonate aqueous solution and ice, filtered, and then dried to obtain a black solid (hereinafter referred to as compound (a-5)) (yield 320 mg). (6) 320 mg of compound (a-5) was placed in a 200 mL three-necked flask under an argon stream, and 70 mL of toluene, 1.0 mL of triethylamine, and 1.5 mL of boron trifluoride diethyl ether complex were added sequentially, and the mixture was heated under reflux for 30 minutes. The organic phase was separated by adding saturated sodium bicarbonate aqueous solution to the reaction mixture, and the organic phase was sequentially washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The crude product obtained was purified by silica gel column chromatography (eluent: toluene / ethyl acetate = 20 / 1 (volume ratio)) to obtain near-infrared fluorescent dye A as green crystals (yield 20 mg, yield 6%). The synthesis flow of near-infrared fluorescent dye A is shown below.

[0171] [ka]

[0172] 《Manufacturing Example 2: Synthesis of Near-Infrared Fluorescent Dye B》 Near-infrared fluorescent dye B was synthesized as follows, referring to Organic Letters, 2012, Vol. 4, pp. 2670-2673, and Chemistry A European Journal, 2009, Vol. 15, pp. 4857-4864. (1) 25.3 g (212 mmol) of 4-hydroxybenzonitrile, 800 mL of acetone, 100 g (724 mmol) of potassium carbonate, and 48 g (249 mmol) of 1-bromooctane were placed in a 2 L four-necked flask and heated under reflux overnight. After filtering the reaction mixture, the acetone was removed by distillation under reduced pressure. Ethyl acetate was added to the residue to separate the organic phase, which was then washed sequentially with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The resulting crude product was purified by silica gel column chromatography (eluent: hexane / ethyl acetate) to obtain 4-octoxybenzonitrile (hereinafter referred to as compound (b-1)) as a colorless transparent liquid (yield 45.2 g, yield 92%). (2) Next, under an argon stream, 25.18 g (224.4 mmol) of tert-butyloxypotassium and 160 mL of tert-amyl alcohol were placed in a 500 mL four-necked flask. Then, a solution of 14.8 g (64 mmol) of compound (b-1) mixed with 7 mL of tert-amyl alcohol was added, and the mixture was heated under reflux. To this mixture, a solution of 6.5 g (32 mmol) of diisopropyl succinate mixed with 10 mL of tert-amyl alcohol was added dropwise over approximately 3 hours, and after the addition was complete, the mixture was refluxed for 6 hours. After the reaction mixture was allowed to cool to room temperature (25°C), it was placed in a mixed solution of acetic acid:methanol:water = 1:1:1 (volume ratio), and heated again under reflux for several minutes, at which point a red solid precipitated. The solid was filtered off and sequentially washed with heated methanol and water to obtain 3,6-(4-octyloxyphenyl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (hereinafter referred to as compound (b-2)) as a red solid (yield 5.6g, yield 32%).

[0173] (3) Meanwhile, 10 g (67 mmol) of 4-tert-butylaniline, 70 mL of acetic acid, and 13 g (160 mmol) of sodium thiocyanate were placed in a 200 mL three-necked flask. While maintaining the internal temperature below 15°C, 4.5 mL (87 mmol) of bromine was added dropwise over approximately 20 minutes. After the addition was complete, the mixture was stirred at below 15°C for 3.5 hours. The reaction mixture was added to 150 mL of 28% aqueous ammonia and stirred. After filtering off the precipitated solid, this solid was extracted with diethyl ether. After washing the extract with water, the crude product obtained by concentrating under reduced pressure was purified by silica gel column chromatography (eluent: dichloromethane / ethyl acetate) to obtain 2-amino-6-tert-butylbenzothiazole (hereinafter referred to as compound (b-3)) as a pale yellow solid (yield 10.32 g, yield 69%). (4) Next, 75.4 g (1340 mmol) of potassium hydroxide and 175 mL of ethylene glycol were placed in a 1 L four-necked flask, and the system was cooled with water under an argon atmosphere. Then, 7.8 g (37.8 mmol) of compound (b-3) was added. After bubbling with argon to remove oxygen from the system, the reaction was carried out at 110 °C for 18 hours. The reaction solution was cooled with water to below 40 °C, and 2 mol / L hydrochloric acid, which had been pre-bubbled with argon, was added dropwise to neutralize the pH to around 7, causing a white solid to precipitate. This white solid was filtered off, washed with water, dried under reduced pressure, and further purified by silica gel column chromatography (eluent: hexane / ethyl acetate) to obtain 4-tert-butyl-2-mercaptoaniline (hereinafter referred to as compound (b-4)) as a white solid (yield 2.39 g, yield 35%). (5) Next, 872 mg (14.5 mmol) of acetic acid and 30 mL of acetonitrile were placed in a 100 mL three-necked flask, and the system was replaced with an argon atmosphere. Then, 2.4 g (36.3 mmol) of malononitrile and 2.39 g (13.2 mmol) of compound (b-4) were added sequentially, and the mixture was heated under reflux for 2 hours. Acetonitrile was removed from the reaction mixture under reduced pressure. Ethyl acetate was added to the residue to separate the organic phase, and the organic phase was sequentially washed with water and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The resulting crude product was purified by silica gel column chromatography (eluent: hexane / ethyl acetate) to obtain 2-(6-tert-butylbenzothiazole-2-yl)acetonitrile (hereinafter referred to as compound (b-5)) as a pale yellow solid (yield 1.98 g, yield 65%).

[0174] (6) Under an argon stream, 1.91 g (3.5 mmol) of compound (b-2), 1.77 g (7.68 mmol) of compound (b-5), and 68 mL of toluene were added to a 200 mL three-necked flask and heated under reflux. 2.56 mL (27.4 mmol) of phosphorus oxychloride was added dropwise to this mixture using a syringe, and the mixture was heated under reflux for a further 2 hours. The reaction mixture was allowed to cool to room temperature (25°C), and while cooling with ice, 40 mL of dichloromethane and 40 mL of saturated sodium bicarbonate aqueous solution were added for extraction. The dichloromethane extract was dried over anhydrous magnesium sulfate and then removed under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: hexane / ethyl acetate) to obtain a crude product from which impurities had been roughly removed. This crude product was purified again by silica gel column chromatography (eluent: hexane / dichloromethane) to obtain a green solid (hereinafter referred to as precursor (b-6)) (yield 1.56 g, yield 46%). (7) Under an argon stream, 1.52 g (1.57 mmol) of precursor (b-6), 45 mL of toluene, 4.35 mL (31.4 mmol) of triethylamine, and 7.88 mL (62.7 mmol) of boron trifluoride diethyl ether complex were added to a 200 mL three-necked flask and heated under reflux for 1 hour. The reaction mixture was cooled on ice, and the precipitated solid was filtered off. The mixture was then sequentially washed with water, saturated sodium bicarbonate aqueous solution, 50% methanol aqueous solution, and methanol, and dried under reduced pressure. The obtained solid was dissolved again in toluene, and then methanol was added to precipitate it, yielding a dark green near-infrared fluorescent dye B with the following NMR spectrum (yield 1.25 g, yield 75%). 1 H-NMR (300MHz, CDCl3): δ7.90ppm(d, 2H), 7.72-7.69(m, 6H), 7.51(dd, 2H), 7.08( d, 2H), 4.07(t, 4H), 1.84(m, 4H), 1.52(s, 18H), 1.35-1.32(m, 24H), 0.92(t, 6H). The synthesis flow of near-infrared fluorescent dye B is shown below.

[0175] [ka]

[0176] Manufacturing Example 3: Synthesis of Near-Infrared Fluorescent Dye C Under an argon stream, 1.52 g (1.57 mmol) of precursor (b-6) obtained according to (1) to (6) of Preparation Example 2, 45 mL of toluene, 4.35 mL (31.4 mmol) of triethylamine, and 12.57 g (62.7 mmol) of diphenylchloroborane were added to a 200 mL three-necked flask and heated under reflux for 1 hour. The reaction mixture was cooled on ice, and the precipitated solid was filtered off. The mixture was then sequentially washed with water, saturated sodium bicarbonate aqueous solution, 50% methanol aqueous solution, and methanol, and dried under reduced pressure. The obtained solid was dissolved again in toluene, and then methanol was added to precipitate it, yielding a dark green near-infrared fluorescent dye C with the following NMR spectrum (yield 1.51 g, yield 73%). 1H-NMR (300MHz, CDCl3): δ7.43ppm(d, 2H), 7.17(m, 8H), 7.08(m, 12H), 6.99(dd, 2H), 6.85(d, 2H), 6.36(m, 4H), 6.31(m, 4H), 3.86(t, 4H), 1.74(m, 4H), 1.5-1.2(m, 20H), 1.12(s, 18H), 0.85(t, 6H). The synthesis flow of near-infrared fluorescent dye C is shown below.

[0177] [ka]

[0178] <Polymerizable compound> <Polyfunctional polymerizable compound> • CN965NS: Polyester-based urethane acrylate (manufactured by Sartomer) Miramer M3130 (product name, manufactured by MIWON, trimethylolpropaneethylene oxide modified triacrylate, viscosity (25℃) 50~70 mPa·s) Miramer M240 (product name, manufactured by MIWON, ethylene oxide-modified bisphenol A type diacrylate, viscosity (25℃) 900~1300 mPa·s) <Monofunctional polymerizable compounds> THFA: ("Viscoat 150", product name, manufactured by Osaka Organic Chemical Industry Co., Ltd., tetrahydrofurfuryl acrylate, viscosity (25℃) 2.8 mPa·s) Miramer M170 (product name, manufactured by MIWON, 2-(2-ethoxyethoxy)ethyl acrylate) IBXA: Isobornyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd.; (meth)acrylate with an alicyclic skeleton, viscosity (25℃) ~15 mPa·s) V-Cap: N-vinylcaprolactam (manufactured by Ashland) Miramer M1182 (product name, manufactured by MIWON, benzyl acrylate (monofunctional (meth)acrylate), viscosity (25℃) 1~10 mPa·s) PHEA: Light Acrylate PO-A (Trade name, manufactured by Kyoeisha Chemical Co., Ltd., Phenoxyethyl acrylate (monofunctional (meth)acrylate), Viscosity (25℃) 8~20 mPa·s) <Photopolymerization initiator> TPO-H: (Trade name, manufactured by IGM RESINS BV, (2,4,6-trimethylbenzoyl)diphenylphosphine oxide) DETX: "Kayacure DETX-S" (product name, manufactured by Nippon Kayaku Co., Ltd., 2,4-diethylthioxanthene-9-one) <Additives (leveling agents)> KF-351A: Polyether-modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd.) <Polymerization inhibitor> BHT: Dibutylhydroxytoluene (manufactured by Seiko Chemical Co., Ltd.)

[0179] 1. Examples of ink composition manufacturing Examples 1-8, Comparative Examples 1-2, Reference Example 1 Ink compositions 1-8, C1-C2, and R1 were prepared by placing each component, such as near-infrared fluorescent dye, polymerizable compound, and polymerization initiator, into a container and stirring and mixing them according to the mixing ratios shown in Table 1.

[0180] 2. Evaluation of the ink composition Each ink composition was dropped onto a substrate (polyvinyl chloride or polycarbonate), and the substrate was irradiated by passing it under UV-LED light to cure the ink and obtain a printed material. Ink ejection was performed using an inkjet recording device with a piezo-type inkjet head. The UV-LED light source for curing emitted ultraviolet light with a wavelength of 385 nm, and the illuminance on the surface was 800 mW / cm². 2 Fixed and varying transport speed, exposure dose 1000 mJ / cm 2 It was exposed to light. For each printed material obtained, the maximum fluorescence intensity measured with a spectrofluorometer FP-8600 (manufactured by JASCO Corporation) was defined as the emission intensity of each printed material. The luminescence intensity for each printed material is shown in Table 1.

[0181] [Table 1]

[0182] Ink compositions 1 to 8 of the present invention can all be observed to emit fluorescence upon irradiation with near-infrared light. On the other hand, ink composition C2, which contains V-Cap as a polymerizable compound, exhibits poor fluorescence observation despite having a high content of near-infrared dye, indicating that the difference in whether or not a vinyl group is directly bonded to a nitrogen atom leads to differences in the confirmation of fluorescence. [Industrial applicability]

[0183] The active energy ray curable ink composition of the present invention, which contains a near-infrared fluorescent dye, exhibits strong fluorescence emission intensity in the near-infrared light region, maintains this intensity over a long period, and is visible under near-infrared light. Such an ink composition can be molded by inkjet printing and is useful for traceability and anti-counterfeiting applications of food and various industrial products.

Claims

1. An active energy ray curable ink composition containing a near-infrared fluorescent dye and a polymerizable compound, wherein the near-infrared fluorescent dye is of the following general formula (I １ ) 【Chemistry 1】 [In formula (I １ )], R ａ and R ｂ together with the nitrogen atom to which R ａ is attached and the carbon atom to which R ｂ is attached form a condensed aromatic ring formed by condensation of an aromatic 5-membered ring, an aromatic 6-membered ring, or 2 to 3 5-membered rings or 6-membered rings; R ｃ and R ｄ together with the nitrogen atom to which R ｃ is attached and the carbon atom to which R ｄ is attached form a condensed aromatic ring formed by condensation of an aromatic 5-membered ring, an aromatic 6-membered ring, or 2 to 3 5-membered rings or 6-membered rings; R[[ID=缉]] ｅ and R ｆ represent a halogen atom or an oxygen atom; R ｇ represents a hydrogen atom or an electron-withdrawing group. However, R ｅ and R ｆ If it is an oxygen atom, R ｅ , R ｅ The boron atom that bonds with R ａ , and R ａ The nitrogen atoms to which it is bonded may together form a ring, R ｆ , R ｆ The boron atom that bonds with R ｃ , and R ｃ The nitrogen atoms to which it is bonded may together form a ring. R ｅ If it is an oxygen atom and does not form a ring, then R ｅ R is an oxygen atom having a substituent, ｆ If it is an oxygen atom and does not form a ring, then R ｆ is an oxygen atom having a substituent. [The compound represented by ] The following general formula (I ２ ) 【Chemistry 2】 [Form (I ２ ) Medium, R ａ ~R ｆ The compound shown is as defined above. The following general formula (I ３ ) 【Transformation 3】 [Form (I ３ ) Medium, R ｈ and R ｉ R ｈ The nitrogen atom and R to which it is bonded ｉ Together with the carbon atom to which it is bonded, it forms an aromatic five-membered ring, an aromatic six-membered ring, or a condensed aromatic ring formed by the condensation of two or three five-membered or six-membered rings; R ｊ and R ｋ R ｊ The nitrogen atom and R to which it is bonded ｋ Together with the carbon atom to which it is bonded, it forms an aromatic five-membered ring, an aromatic six-membered ring, or a condensed aromatic ring formed by the condensation of two or three five-membered or six-membered rings; R ｌ , R ｍ , R ｎ , and R ｏ These are halogen atoms, C, independently of each other. １－２０ alkyl group, C １－２０ R represents an alkoxy group, an aryl group, or a heteroaryl group; ｐ and R ｑ These are hydrogen atoms, halogen atoms, and C, which are independent of each other. １－２０ alkyl group, C １－２０ R represents an alkoxy group, an aryl group, or a heteroaryl group. ｒ and R ｓ These independently represent a hydrogen atom or an electron-withdrawing group. Compounds represented by ], and The following general formula (I ４ ) 【Chemistry 4】 [Form (I ４ ) Medium, R ｈ ~R ｑ [This is as defined above] One or more compounds selected from the group consisting of the compounds shown, An active energy ray curable ink composition wherein the maximum fluorescence wavelength of the near-infrared fluorescent dye is 650 nm or higher.

2. The active energy ray curable ink composition according to claim 1, wherein the near-infrared fluorescent dye is dissolved.

3. The active energy ray curable ink composition according to claim 1, wherein the polymerizable compound has the function of dissolving the near-infrared fluorescent dye.

4. The polymerizable compound does not have a vinyl group directly bonded to a nitrogen atom, as described in claim 3.

5. The active energy ray curable ink composition according to claim 1, wherein the content of the near-infrared fluorescent dye is in the range of 50 to 500 ppm relative to the total mass of the active energy ray curable ink composition.

6. Furthermore, the active energy ray curable ink composition according to claim 1 further contains a photopolymerization initiator.

7. The active energy ray curable ink composition according to claim 1, which does not contain a solvent.

8. The active energy ray curable ink composition according to claim 1, which is formed by an inkjet method.

9. A cured product of an active energy ray curable ink composition according to any one of claims 1 to 8.

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