JP2011241332A - Infrared absorptive composition, infrared absorptive ink, recorded matter, image recording method, and image detecting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infrared absorptive composition excellent in light resistance.SOLUTION: The infrared absorptive composition includes the following (A) component and the following (B) component, wherein the total content of an infrared absorption pigment chosen from the group consisting of infrared absorption pigments of (B) component is at least 50 ppm and at most 100,000 ppm: (A) at least one sort chosen from copper phthalocyanine infrared absorption pigments having an arylthio group expressed by a specific general formula; and (B) at least one sort chosen from the group consisting of a phthalocyanine infrared absorption pigment having an arylthio group, not containing a metal, and expressed with a specific general formula or phthalocyanine infrared absorption pigments having an arylthio group, containing a metal other than copper, and expressed with a specific general formula.

Description

  The present invention relates to an infrared absorbing composition, and an infrared absorbing ink, a recorded material, an image recording method, and an image detection method using the same.

  Near-infrared absorbing dyes that do not substantially absorb visible light but absorb infrared light are widely used in various optoelectronic products such as near-infrared absorbing filters.

  Optoelectronic products may be exposed to high temperatures, high humidity, or light irradiation depending on the usage mode such as outdoor use such as security-related equipment such as authentication of characters and images. For this reason, it is important that the near-infrared absorbing dye used is stable over a long period of time, and it is required to have a stability that hardly degrades performance due to decomposition over time. In particular, it is indispensable that the pigment itself has resistance to light in order to maintain high product quality for a long period of time.

  As a technology related to the above, as a near infrared absorber excellent in light resistance, weather resistance, and heat resistance, a naphthalocyanine near infrared absorber and an alkyl phthalocyanine near infrared absorber having a specific structure have been proposed (for example, Patent References 1-2).

  Further, as a near-infrared-absorbing ink that hardly absorbs visible light, a near-infrared-absorbing ink that is excellent in light resistance by containing a specific naphthalocyanine compound has been disclosed (for example, see Patent Document 3).

JP-A-2-43269 JP-A-2-138382 JP-A-3-79683

  However, the above-described conventional infrared absorbers do not have sufficient performance required for the infrared absorber, such as absorption wavelength and weather resistance, and further light resistance is required to be improved.

  However, although various techniques have been proposed for suppressing dye decomposition by light, the actual situation is that the decomposition of the dye by light has not been sufficiently suppressed.

  The present invention has been made in view of the above, an infrared absorbing composition excellent in light resistance, and an infrared absorbing ink capable of stably reading image information over a long period of time, a recorded matter, an image recording method, It is another object of the present invention to provide an image detection method and to achieve the object.

Specific means for achieving the above object are as follows.
<1> Infrared absorbing dye selected from the group consisting of infrared absorbing dyes containing the following (A) component and the following (B) component and represented by the following general formula (2) or the following general formula (3) Is an infrared absorbing composition having a total content of 50 ppm or more and 100,000 ppm or less.
(A) At least one selected from infrared absorbing dyes represented by the following general formula (1) (B) From the group consisting of infrared absorbing dyes represented by the following general formula (2) or the following general formula (3) At least one selected

[In General Formula (1), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. ]

[In General Formula (2), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. ]

[In General Formula (3), M is a divalent atom including two atoms, a divalent metal atom, or a trivalent or tetravalent metal atom selected from the group consisting of a hydrogen atom and a monovalent metal atom. Represents a substituted metal atom. However, as said M, a copper atom is remove | excluded. Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. ]

<2> The total content of infrared absorbing dyes selected from the group consisting of the infrared absorbing dyes represented by the general formula (2) or the general formula (3) is 100 ppm or more and 100000 ppm or less. Infrared absorbing composition.
<3> The infrared absorbing composition according to <1> or <2>, further including an organic solvent.
<4> The infrared content represented by the general formula (1) is a total content of the infrared absorbing pigment selected from the group consisting of the infrared absorbing pigment represented by the general formula (2) or the general formula (3). The infrared absorbing composition according to any one of <1> to <3>, wherein the composition is 0.0001 times or more and 0.1 times or less with respect to the content of the absorbing dye.

<5> An infrared absorbing ink containing the infrared absorbing composition according to any one of <1> to <4>.
<6> A recorded matter having an image made of the infrared absorbing ink according to <5> above on a recording medium.
<7> An image recording method comprising a step of forming an image by applying the infrared absorbing ink according to <5> above on a recording medium.
<8> An image detection method including a step of detecting, with an infrared detector, image information of the image formed on the recording medium by the image recording method according to <7>.

ADVANTAGE OF THE INVENTION According to this invention, the infrared rays absorptive composition excellent in light resistance can be provided. Also,
According to the present invention, it is possible to provide an infrared absorbing ink, a recorded material, an image recording method, and an image detection method capable of stably reading image information for a long period of time.

  Hereinafter, the infrared absorbing composition of the present invention, the infrared absorbing ink, the recorded matter, the image recording method, and the image detection method will be described in detail.

<Infrared absorbing composition>
The infrared absorbing composition according to the present invention comprises the following (A) component and the following (B) component, and comprises an infrared absorbing dye represented by the following general formula (2) or the following general formula (3). The total content of the infrared absorbing dye selected from the group has a configuration of 50 ppm to 100,000 ppm.
(A) At least one selected from infrared absorbing dyes represented by the following general formula (1) (B) Infrared represented by the following general formula (2) or the following general formula (3) At least one selected from the group consisting of absorbing dyes

  In the present invention, as an infrared absorber, in addition to at least one selected from the infrared absorbing dyes represented by the general formula (1) (component (A)), the general formula (2) or the general formula ( 3) Infrared absorbing dye containing at least one selected from the group consisting of infrared absorbing dyes represented by 3) (component (B)) and represented by the general formula (2) or the general formula (3) By controlling the total content of these to a constant amount, the resistance to light (light resistance) can be drastically improved in a liquid such as a composition or an ink using the composition or in an image formed thereby.

(A) Infrared absorbing dye represented by general formula (1) (component (A))
The infrared absorbing composition of the present invention contains at least one (component (A)) selected from infrared absorbing dyes represented by the following general formula (1).

In General Formula (1), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. Ar _{1 to} Ar ₈ may be the same or different from each other.

The aryl group represented by Ar _{1 to} Ar ₈ may be unsubstituted or substituted, and is preferably an aryl group having 6 to 16 carbon atoms, more preferably an aryl group having 6 to 12 carbon atoms. preferable. Among these, an alkylphenyl group and / or an alkoxyphenyl group (preferably, the number of carbon atoms in the alkyl moiety is 1 to 10 is preferred). Examples of the aryl group include phenyl group, 2,4-dimethylphenyl group, 2-methylphenyl group, 4-methylphenyl group, 2-ethylphenyl group, 4-ethylphenyl group, 2-methoxyphenyl group, 4- Examples include methoxyphenyl group, 4-octyloxyphenyl group, 4-t-butylphenyl group, naphthyl group and the like.
Among these, 2,4-dimethylphenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-t-butylphenyl group, and naphthyl group are particularly preferable.

  Hereinafter, specific examples of the infrared absorbing dye represented by the general formula (1) will be shown. However, the present invention is not limited to these compounds.

(B) Infrared absorbing dye represented by general formula (2) or general formula (3) (component (B))
The infrared absorbing composition of the present invention contains at least one (component (B)) selected from the group consisting of infrared absorbing dyes represented by the following general formula (2) or the following general formula (3).

In General Formula (2), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ have the same meanings as in General Formula (1). Ar _{1 to} Ar ₈ may be the same or different from each other.

The aryl group represented by _Ar 1 to Ar ₈ in the general formula (2), include the same ones listed as the aryl group represented by _Ar 1 to Ar ₈ in the general formula (1) It is done. Among these, 2,4-dimethylphenyl group, 4-methylphenyl group, 4-methoxyphenyl group, 4-t-butylphenyl group, and naphthyl group are particularly preferable.

  Hereinafter, specific examples of the infrared absorbing dye represented by the general formula (2) will be shown. However, the present invention is not limited to these compounds.

In general formula (3), M is a divalent atom containing two atoms, a divalent metal atom, or a trivalent or tetravalent metal atom selected from the group consisting of a hydrogen atom and a monovalent metal atom. Represents a substituted metal atom. However, as said M, a copper atom is remove | excluded. Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ have the same meanings as those in the general formula (1). Ar _{1 to} Ar ₈ may be the same or different from each other.

  In the general formula (3), preferable M includes two hydrogen atoms, a divalent metal atom, a divalent metal oxide, a divalent metal hydroxide, or a divalent metal chloride. .

Specific examples of M include Li, Na, Ca, Al (OH), AlCl, FeCl, Fe (OH), VO, TiO, Zn, Mg, Si, Sn, Rh, Pt, Pd, Mo, Mn, and Pb. _{, Ni, Mg, Sn, Pd} , Co, Fe, InCl, TiCl 2, SnCl 2, SiCl 2, GeCl 2, Si (OH) 2, H 2 , and the like.
Especially, the aspect whose M is Li, Na, Ca, Al (OH), AlCl, FeCl, and Fe (OH) is preferable.

The aryl group represented by _Ar 1 to Ar ₈ in the general formula (3), include the same ones listed as the aryl group represented by _Ar 1 to Ar ₈ in the general formula (1) It is done. Among these, 2,4-dimethylphenyl group, 4-methylphenyl group, 4-t-butylphenyl group, and naphthyl group are particularly preferable.

  Hereinafter, specific examples of the infrared absorbing dye represented by the general formula (3) will be shown. However, the present invention is not limited to these compounds.

In the infrared absorbing composition of the present invention, the total content of the infrared absorbing dye selected from the group consisting of the infrared absorbing dye represented by the general formula (2) or the general formula (3) is 50 ppm or more and 100,000 ppm or less. Furthermore, 100 ppm or more and 100,000 ppm or less are preferable, and 120 ppm or more and 100,000 ppm or less are more preferable. Furthermore, 200 ppm or more and 50000 ppm or less are preferable, and 250 ppm or more and 10000 ppm or less are particularly preferable.
When the total content is less than 50 ppm, good dispersion stability cannot be obtained and the readability upon image recording is poor. On the other hand, when it exceeds 100000 ppm, good light resistance cannot be obtained and image recording is performed. There is a disadvantage that it is inferior in readability.

(Method for synthesizing infrared absorbing dye in the present invention)
The infrared absorbing dye in the present invention containing the component (A) and the component (B) is synthesized using a compound represented by the following general formula (X) as a raw material. Preferably, a method of providing a step of synthesizing the infrared absorbing material by reacting a compound represented by the following general formula (X) in the presence of lithium halide in an organic solvent.
A synthesis method using the compound represented by the general formula (X) as a raw material is represented by the following formula.

In General Formula (X), General Formula (2a), and General Formula (1a), Ar ₉ and Ar ₁₀ each independently represent a substituted or unsubstituted aryl group.

The synthesis step of synthesizing the compound of the general formula (2a) from the compound of the general formula (X) can be preferably performed in a high yield by reacting in the presence of lithium halide in an organic solvent. More preferably, it is carried out in the presence of alcoholate (for example, sodium alcoholate, potassium alcoholate, etc.) and hydroquinone.
For example, when t-butanol alcoholate (t-BuOM ³ , M ³ : alkali metal (for example, Na, K, etc.)) is used as the alcoholate, the preferred amount of t-BuOM ³ is the general formula (X) as a raw material. The molar amount is preferably 0.1 to 20 times the molar amount, more preferably 1 to 8 times the molar amount, and particularly preferably 2 to 4 times the molar amount. Further, the preferred amount of lithium halide is preferably 0.1 to 50 times the molar amount of the compound of the general formula (X) as the raw material, and more preferably 1 to 15 times the molar amount. Is more preferable, and a molar amount of 3 times or more and 10 times or less is particularly preferable.

  As the solvent for the reaction, an alcohol having 1 to 20 carbon atoms is preferably used, more preferably an alcohol having 1 to 10 carbon atoms, and more preferably methanol, ethanol, 1-propanol, 2-propanol, 1 -Butanol, 2-butanol, t-butanol, 1-pentanol, 2-pentanol, i-pentanol, t-pentanol, 1-octanol, 2-octanol, particularly 1-butanol is preferable. . The amount of alcohol used as a solvent is preferably 0.1 to 50 times, more preferably 1 to 15 times the phthalonitrile compound represented by the general formula (X) as a raw material. Is more preferable, and 2 times or more and 6 times or less are particularly preferable. In addition to these solvents, amide solvents (for example, N, N-dimethylformamide, N, N-dimethylacetamide, 1-methyl-2-pyrrolidone), sulfone solvents (for example, sulfolane), sulfoxide solvents (for example, Dimethyl sulfoxide), ether solvents (eg dioxane, cyclopentyl methyl ether), ketone solvents (eg acetone, cyclohexanone), hydrocarbon solvents (eg toluene, xylene), halogen solvents (eg tetrachloroethane, chlorobenzene), pyridine series It is also preferable to mix a solvent (for example, pyridine, γ-picoline, 2,6-lutidine).

Furthermore, the reaction is preferably performed in the presence of hydroquinone. The preferred amount of hydroquinone is preferably 0.05 to 5 times the molar amount of the compound represented by the general formula (X) as a raw material, and more preferably 0.1 to 3 times the molar amount. The following is more preferable, and 0.2 to 2 times the molar amount is particularly preferable. The addition of hydroquinone is preferable even when the raw material compound represented by the general formula (X), lithium halide, and t-BuOM ³ are added, and even after completion of the temperature rise, the reaction starts to ends. It is preferable anytime immediately before.

  The reaction temperature is preferably -30 ° C to 250 ° C, more preferably 0 ° C to 200 ° C, still more preferably 20 ° C to 150 ° C, particularly preferably 50 ° C to 120 ° C, and the reaction time is 5 minutes to 30 hours. A range is preferred.

  The synthesis step of synthesizing the compound of the general formula (1a) from the compound of the general formula (2a) can be performed by a conventionally known reaction for introducing a copper (Cu) atom into a phthalocyanine nucleus. For example, it can be carried out under the conditions disclosed in JP-A-60-209583.

  In each step of the synthesis, water is used for cooling and washing. At this time, not only the infrared absorbing dye (component (A)) represented by the general formula (1) but also the infrared absorbing dye represented by the general formula (2) or the general formula (3). The total content of infrared absorbing dyes selected from the group consisting of infrared absorbing dyes containing infrared absorbing dyes (component (B)) and represented by the general formula (2) or the general formula (3) is 50 ppm. From the viewpoint of adjusting to 100000 ppm or less, it is preferable to use tap water as the water.

  In the infrared absorbing composition of the present invention, the total content of infrared absorbing dyes selected from the group consisting of infrared absorbing dyes represented by the general formula (2) or the general formula (3), A ratio (mass basis) to the content of the infrared absorbing dye represented by the general formula (1) is preferably 0.0001 times or more and 0.1 times or less. Furthermore, 0.001 times or more and 0.05 times or less are more preferable, and 0.002 times or more and 0.01 times or less are particularly preferable. When the ratio is 0.0001 times or more, good dispersibility is obtained, and the readability when an image is recorded is excellent. On the other hand, being 0.1 times or less is advantageous in terms of light resistance.

  Moreover, as content of the infrared rays absorption pigment | dye represented by the said General formula (1) in the infrared rays absorptive composition of this invention, 0.1-80 mass% is preferable with respect to the composition total mass, and 1 -70 mass% is more preferable. When the content of the infrared-absorbing dye represented by the general formula (1) is 0.1% by mass or more, it is advantageous in terms of excellent readability when an image is recorded. If present, it is advantageous in terms of the dispersion stability of the ink.

  The infrared absorbing composition of the present invention may contain an organic solvent. Furthermore, the infrared absorbing composition of the present invention can be constituted using a resin depending on various conditions such as application and use environment or as required, and in addition, a surfactant, other solvent, a curing agent for the resin, etc. Other components may be used.

(C) Organic solvent The infrared absorbing composition of the present invention may contain an organic solvent.
Examples of the organic solvent in the present invention include aromatic or aliphatic hydrocarbons, ketones, esters, ethers, alcohols, and liquid polymerizable compounds.

  Examples of the aromatic or aliphatic hydrocarbon include n-hexane, n-octane, toluene, ethylbenzene, xylene, and benzene.

  Examples of the ketone include methyl isobutyl ketone, methyl isopropyl ketone, methyl ethyl ketone, and methyl propyl ketone.

  Examples of the ester include ethyl acetate, butyl acetate, isobutyl acetate, isopropyl acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monobutyl ether acetate (BMGAC), diethylene glycol monoethyl ether acetate (EDGAC), and the like.

  Examples of the ether include diethyl ether.

  Examples of the alcohol include n-butanol, n-hexanol, isopropyl alcohol, cyclohexanol, diethylene glycol monobutyl ether (BDG), diethylene glycol monoethyl ether (EDG), ethylene glycol monoethyl ether (EMG), and the like.

The polymerizable compound is a monomer compound having a polymerizable group such as an ethylenic double bond, and examples thereof include (meth) acrylic monomers.
Examples of the (meth) acrylic monomer include methyl methacrylate, cyclohexyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, n-butyl acrylate, and allyl methacrylate.

  Commercially available products that are marketed as the polymerizable compound may be used. Examples of the commercially available products include Kayrad series (for example, Kayrad TMPTA, DPHA, TPGDA, etc.) manufactured by Nippon Kayaku Co., Ltd. Can be used.

In addition, an organic solvent may be used individually by 1 type, or may use 2 or more types of organic solvents together.
As content in the infrared absorptive composition of the organic solvent in this invention, it is the infrared absorption pigment | dye in the said this invention (The infrared absorption pigment | dye represented by the said General formula (1), General formula (2), or General formula (3 1 to 1,000,000% by mass, and more preferably 10 to 500,000% by mass with respect to the content of all infrared absorbing pigments including the infrared absorbing pigment represented by When the content of the organic solvent is 1% by mass or more, the dispersibility of the infrared absorbing dye and its stability over time are good, and when it is 1,000,000% by mass or less, the desired infrared absorption is achieved. This is advantageous in terms of reading sensitivity.

(D) Resin The infrared absorbing composition of the present invention may contain a resin. There is no restriction | limiting in particular in resin, According to a use, an objective, etc., it can select.

  Preferred examples of the resin include rosin and modified rosin and derivatives thereof, rosin and modified products thereof, petroleum resins, dicyclopentadiene resins and modified products thereof.

  The rosin is a natural resin mainly composed of rosin acid. Examples of the modified rosin and the derivative of the modified rosin include polymerized rosin (for example, rosin acid ester resin), disproportionated rosin, hydrogenated rosin, maleic acid-modified rosin and the like.

  The petroleum resin is obtained by polymerizing an unsaturated compound having a large number of carbon atoms when naphtha is decomposed, and includes an aliphatic system using a C5 fraction as a raw material, an aromatic system using a C9 fraction as a raw material, and a copolymer system. included. Examples of petroleum resins include dicyclopentadiene petroleum resins and aromatic petroleum resins.

  Examples of the modified product of the dicyclopentadiene resin include modified products such as unsaturated polyester modification and phenol modification.

  The content of the resin in the infrared absorbing composition is preferably 1% or more and 99% or less, more preferably 10% or more and 98% or less, in terms of mass ratio with respect to the total solid content of the composition. When the content of the resin is 1% by mass or more, it is advantageous in terms of solvent resistance of the printed material, and can be 99% by mass or less from the viewpoint of reading sensitivity of the printed material by infrared light.

(E) Other components The infrared absorbing composition of the present invention may be prepared using a surfactant, a solvent other than the organic solvent, a resin curing agent, or the like, if necessary, in addition to the above components. it can.

  Examples of the surfactant include nonionic surfactants such as alkylene oxide, glycerin, glycidol, and alkylphenol ethylene oxide adducts, cyclic amines, ester amides, quaternary ammonium salts, hydantoin derivatives, and heterocyclic rings. , Cationic surfactants such as phosphonium or sulfonium, anionic surfactants containing acidic groups such as carboxylic acid groups, sulfonic acid groups, and sulfate ester groups, or amino acids, aminosulfonic acids, sulfuric acid or phosphorus of amino alcohols Acid esters, amphoteric surfactants such as alkylbetaine type, and the like can be used.

The infrared absorbing composition of the present invention may be prepared by previously dispersing an infrared absorbing dye in an organic solvent and adding a resin thereto. At this time, a dispersant for dispersing the infrared absorbing dye can be contained. In this case, in addition to adding the surfactant as the additive, the surfactant may be used as a dispersant. The surfactant used as the dispersant is preferably a nonionic surfactant, an anionic surfactant, or a cationic surfactant, more preferably a nonionic surfactant or an anionic surfactant, An anionic surfactant is preferred. Furthermore, it is preferably an organic sulfonic acid metal salt having 40 or less carbon atoms, more preferably an organic sulfonic acid metal salt having 30 or less carbon atoms, and most preferably a sodium or potassium salt of an organic sulfonic acid having 25 or less carbon atoms. It is.
In addition, when adding a dispersing agent, the timing of the addition of a dispersing agent is the process which disperse | distributes an infrared-absorbing pigment | dye in the solvent in the process in which a pigment particle is disperse | distributed, or a dispersant is added to a solvent. It is preferable to add them later, and among them, the method of adding a dispersant in the process of dispersing as in the former is most preferable.

  Moreover, you may contain solvents other than the above-mentioned (c) organic solvent in the range which does not impair the effect of this invention. Examples of the solvent include a dispersion medium described in paragraph [0071] of JP-A-2008-105958.

  Moreover, the infrared ray absorbing composition of the present invention may contain the resin (d) curing agent. Examples of the curing agent include polyisocyanate resins for urethane resins. A hardening | curing agent can be used in 1-70 mass% with respect to resin.

The infrared-absorbing composition of the present invention forms the infrared-absorbing layer by dispersing the infrared-absorbing dye in the present invention in a resin and coating or hard-coating it on the surface of paper, resin sheet or film, glass, metal plate, etc. Infrared absorption by preparing an infrared-absorbing resin by polymerizing the mixture by adding it to a resin raw material such as a monomer, or by adding it to a resin and melting it by heating and dispersing it in a molten resin The desired infrared absorbing material can be produced by applying the method to a method for preparing a functional resin.
Among these, the infrared absorptive ink using the infrared absorptive composition of this invention is demonstrated below.

<Infrared absorbing ink and recorded matter>
The infrared absorbing ink of the present invention is constituted by using the above-described infrared absorbing composition of the present invention. This infrared absorbing ink is excellent in light resistance since the infrared absorbing composition described above is used.

  The infrared-absorbing ink of the present invention contains at least the infrared-absorbing composition of the present invention, and, depending on the application and purpose, further, a colorant, a polymerization initiator, and a polymerizable compound not included in the organic solvent Other additives can be used.

  By containing the colorant, an ink colored in a desired hue can be obtained. Examples of the colorant include pigments and dyes. A coloring agent can be contained in the range which does not impair the effect of this invention.

In addition, when a polymerizable compound or a resin in the ink has a polymerizable group, by containing a polymerization initiator, the polymerizable group contained in the ink can be polymerized to cure the ink. it can. Thereby, the intensity | strength (for example, abrasion resistance) of a recorded image can be improved.
The polymerization initiator can be used as long as it is a compound capable of generating an active species that initiates a polymerization reaction of a polymerizable group such as a monomer component, and can be appropriately selected from known photopolymerization initiators and the like. For example, trihalomethyl group-containing compounds, acridine compounds, acetophenone compounds, bisimidazole compounds, triazine compounds, benzoin compounds, benzophenone compounds, α-diketone compounds, polynuclear quinone compounds, xanthone compounds, diazo compounds Compound, etc. can be mentioned.

  The recorded matter of the present invention is constituted by providing an image using the above infrared absorbing ink. The recorded matter of the present invention uses the above-described infrared absorbing composition, and therefore has better light resistance than conventional ones.

  Examples of the image include various marks such as marks, marks, etc. (eg, copy prevention marks), characters (eg, security authentication characters), pictures, barcodes, and the like.

<Image recording method>
The image recording method according to the present invention comprises a step of recording an image by applying the above-described infrared absorbing ink of the present invention on a recording medium. In the image recording method of the present invention, an image is formed with an infrared absorbing ink using the above-described infrared absorbing composition, so that the recorded image is excellent in light resistance.

  The application of the infrared absorbing ink at the time of image recording can be performed using a known method such as a coating method, a printing method, an ink jet method or the like. As a coating method, for example, a bar coat or the like can be applied. As a printing method, gravure printing, lithographic printing or the like can be applied. In addition, as an ink jet method, a charge control method that discharges ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) that uses vibration pressure of a piezo element, and bubbles are formed by heating the ink. Any of the thermal (Bubble Jet (registered trademark)) method using the generated pressure can be applied.

  After applying the ink, other steps such as a step of drying the ink and a step of (thermo) compression of the recorded image can be provided.

<Image detection method>
The image detection method according to the present invention comprises a step of detecting image information of an image formed on a recording medium by the above-described image recording method of the present invention with an infrared detector. Since the image to be detected has good light resistance, the detection ability (readability, etc.) when detected by the infrared detector can be kept stable for a long time.

  Image information in an image is detected by irradiating the recording surface of the recorded matter on which the image is recorded with infrared rays using an infrared detector to detect various pieces of image information. The image portion containing the infrared absorbing dye is not visually recognized or difficult to be recognized in the composition that is not colored, but when the infrared ray is irradiated, the region containing the infrared absorbing dye absorbs the infrared ray. Reflected light and fluorescence at the time of irradiation can be detected, and pattern information such as marks such as symbols and dots, characters, pictures, barcodes, and image information such as position information can be read.

  As the infrared detector, an apparatus that can detect by irradiating infrared rays and receiving reflected light or the like at the time of irradiation can be used. The detection can be suitably performed using wavelength light having a wavelength of 800 to 1200 nm. As the light source, a light source that emits infrared light may be used, or a light source that emits light including light having a wavelength other than infrared light may be used.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof. Unless otherwise specified, “part” and “%” are based on mass.

<Example 1>
-Synthesis of Infrared Absorbing Dye Mixture Powder 1-
An infrared absorbing dye mixture powder 1 containing the following exemplary compound (1) (the above-mentioned compound 1) and containing the above-mentioned compound 6, compound 14, and compound 22 was synthesized by the following synthesis route.

1) Synthesis of Z1-B 100 g of 2,3-dicyano-1,4-dihydroquinone (Z1-D), 259 g of potassium carbonate, and 900 mL of acetone were placed in a 3 L three-necked flask and p- After adding 262 g of toluenesulfonic acid chloride in portions, the mixture was stirred for 2 hours under reflux. After cooling to an internal temperature of 50 ° C., 1000 mL of tap water was added dropwise and cooled to 10 ° C. over 2 hours. The obtained slurry was filtered and washed with 300 mL of methanol and 300 mL of tap water to obtain 214 g of the compound (Z1-C) (yield 73%). Next, 50 g of 4-methylthiophenol, 55.8 g of potassium carbonate, and 590 mL of DMAc (dimethylacetamide) are placed in a 2 L three-necked flask, and 90 g of the above compound (Z1-C) is added in portions at an internal temperature of 30 ° C. or lower, and the mixture is stirred for 2 hours. did. After adding 1200 mL of tap water over 10 minutes and stirring at room temperature for 1 hour, the obtained slurry was filtered and washed with 4 L of tap water to obtain 46.6 g of the compound (Z1-B) ( Yield 65%)

2) Synthesis of infrared absorbing dye mixture 30 g of the above compound (Z1-B), lithium chloride 16.4 g, t-butoxypotassium 21.7 g and butanol 300 mL were placed in a 1000 mL three-necked flask and heated at 100 ° C. for 6 hours. . Thereafter, 1.3 g of hydroquinone was added and stirred for 1 hour, and then cooled to 50 ° C., and 210 mL of tap water and 105 mL of acetic acid were added. The obtained slurry was filtered, and washed with 200 mL of tap water and 300 mL of methanol to obtain 30 g (yield 64.6%) of the compound (Z1-A). When the obtained compound was measured by MS spectrum, a peak corresponding to the molecular weight was obtained.
15 g of the above compound (Z1-A) was dissolved in 1 L of THF (tetrahydrofuran), 3.65 g (2.0 equivalents) of copper acetate was added, and the mixture was stirred at 30 ° C. for 4 hours. After cooling the reaction solution, tap water was added, and the resulting slurry was filtered, washed with 100 mL of methanol and dried to obtain 14.7 g of an infrared absorbing dye mixture (yield 94%). The obtained powder is designated as infrared absorbing dye mixture powder 1.

3) Analysis of composition of infrared absorbing dye mixture powder The compound contained in the infrared absorbing dye mixture powder 1 was analyzed and its content was measured using high performance liquid chromatography.
As described above, the infrared absorbing dye mixture powder 1 contains the exemplified compound (1) (the above-mentioned compound 1), and the above-mentioned compound 6, the compound 14, and the compound 22. The respective contents are shown in Table 1 below.

-Synthesis of Infrared Absorbing Dye Mixture Powders 2-5-
In the same manner as the infrared absorbing dye mixture powder 1, lots in which only the synthesis scale was changed were designated as infrared absorbing dye mixture powders 2 to 5. The composition of the mixture is shown in Table 1 below.

-Synthesis of infrared absorbing dye mixture powder 6 (for comparison)-
In addition, in the synthesis of the infrared absorbing dye mixture powder 1, all the “tap water” used was changed to “ion exchange water” and the synthesis lot was changed in the same manner except that the synthesis scale was changed. It was set to 6. The composition of the mixture is shown in Table 1 below.

-Preparation of printing ink-
Using the infrared absorbing dye mixture powders 1 to 6 obtained above, the components in the composition shown below were mixed to prepare an infrared absorbing printing ink.
<Infrared absorbing printing ink composition>
・ Infrared absorbing dye mixture powder shown in Table 2 below 5 parts ・ Vinyl chloroacetate resin 15 parts (trade name: Elex A, manufactured by Sekisui Chemical Co., Ltd.)
・ Saturated polyester (trade name: Byron 103, manufactured by Toyobo Co., Ltd.) 5 parts ・ Polyurethane elastomer ... 12 parts (trade name: N-2304, manufactured by Nippon Polyurethane Co., Ltd.)
・ Isocyanate curing agent 3 parts (trade name: JA-960, manufactured by Jujo Chemical Co., Ltd.)
・ Triethylenediamine: 0.5 part ・ Solvent: 70 parts (Toluene / methyl isobutyl ketone = 70/30 [mass ratio])

-Image recording-
Using each of the infrared absorbing printing inks obtained as described above, a barcode pattern was formed by gravure printing on plain paper MP-120 (manufactured by Plus Co.) as a base paper.

  Next, on the barcode pattern formed as described above, three kinds of process inks having infrared transparency (FDOL yellow, FDOL magenta, FDOL cyan, manufactured by Toyo Ink Manufacturing Co., Ltd.) are obtained by gravure printing. By giving and forming a colored layer composed of three visible colors (indigo, red, yellow), a printed matter having a barcode pattern arranged therein was produced.

  In the obtained printed matter, the entire color layer of visible colors (indigo, red, yellow) is visible, but the barcode pattern is almost invisible, so the presence of the barcode pattern itself cannot be discerned with the naked eye Met.

  The printed matter was irradiated with two types of semiconductor laser light having a wavelength of 830 nm and a wavelength of 905 nm, and the emitted light having a wavelength of 950 nm or less was detected through a filter. At this time, the pattern formed with the infrared absorbing ink could be read.

  Subsequently, 70,000 lux of xenon light was continuously irradiated for 200 hours to the printed matter by a xenon lamp. Thereafter, the degree of reading of the barcode pattern after irradiation was evaluated. In the evaluation, a case where the PCS (print contrast signal) was 0.6 or more was rated as “good”, and a case where the PCS (print contrast signal) was less than 0.6 was rated as “bad”. . The evaluation results are shown in Table 2 below.

  As shown in Table 2, it is clear that the printed matter of the present invention has high light resistance of the barcode pattern in the printed matter.

<Example 2>
Using the infrared absorbing dye mixture powders 1 to 6 obtained above, components in the composition shown below were kneaded to prepare an ultraviolet curable ink having infrared absorptivity.
<Composition of UV curable ink>
Photomer 5018 ... 60 parts (aliphatic polyester tetraacrylate; manufactured by San Nopco)
・ Kayarad TMPTA ... 14 parts (Trimethylolpropane triacrylate; manufactured by Nippon Kayaku Co., Ltd.)
・ Kaya Cure MBP 1 part (3,3′-dimethyl-4-methoxybenzophenone; manufactured by Nippon Kayaku Co., Ltd.)
・ Nisso Cure TX (thioxanthone; manufactured by Nippon Soda Co., Ltd.) 8 parts ・ Sandry 1000 ... 1 part (4-phenoxydichloroacetophenone: manufactured by Sand Corp.)
・ White petrolatum ・ ・ ・ 4 parts ・ Infrared absorbing pigment mixture powder shown in Table 3 below ・ ・ ・ 12 parts

  Using the obtained ultraviolet curable ink, a copy prevention mark was gravure-printed on the same base paper as in Example 1. Each of the process inks (FDOL Yellow, FDOL Magenta, FDOL Cyan, Toyo Ink Manufacturing Co., Ltd.) is formed on the printed copy protection mark in layers by gravure printing, or these three types of process inks are used. The mixed ink mixture was provided in a layer form by gravure printing, thereby concealing the copy protection mark to obtain a printed matter.

  Copy protection marks concealed with process ink are irradiated with infrared rays using a linear sensor (TCD1500C, manufactured by Toshiba Corp.) as the detection device instead of the infrared cut filter (IR83, manufactured by HOYA). At the same time, the reflected light was detected.

  The copy protection mark could not be visually recognized in the colored layer of process ink, but by using the detection device described above, the copy prevention mark was not detected in the infrared region without detecting a print layer of three types of process ink. Only was able to be detected. That is, since the three types of process inks do not absorb in the infrared region, only the anti-copy mark having infrared absorptivity existing in the lower part can be detected.

  The case where the value obtained by dividing the reflected light intensity of the area of the anti-copy mark when the anti-copy mark is detected by the reflected light intensity of the area other than the anti-copy mark is used as the comparative infrared absorbing dye mixture powder 3 The ratio was calculated by normalizing to “1”. The results are shown in Table 3 below.

  The obtained printed matter was continuously irradiated with 70,000 lux of xenon light for 144 hours by a xenon lamp. After irradiation, the value obtained by dividing the reflected light intensity in the area of the copy protection mark by the reflected light intensity in the area other than the copy protection mark is obtained in the same manner as described above, and the rate of change [%] from the value before irradiation is calculated. It was used as an index for evaluating light resistance. The results are shown in Table 3 below.

  As shown in Table 3, the ultraviolet curable ink of the present invention had high detection sensitivity and extremely excellent light resistance.

<Example 3>
-Synthesis of Infrared Absorbing Dye Mixture Powder 7-
Except that 4-t-butylthiophenol was used instead of 4-methylthiophenol used in synthesizing the compound (Z1-B) in preparing the infrared absorbing dye mixture powder 1 in Example 1. In the same manner as in Example 1, an infrared-absorbing dye mixture powder 7 containing the aforementioned compound 2 and containing the aforementioned compound 7 and compound 15 was synthesized.

-Analysis of composition of infrared absorbing dye mixture powder The compound contained in the infrared absorbing dye mixture powder 7 was analyzed and its content was measured using high performance liquid chromatography.
As described above, the infrared absorbing dye mixture powder 7 contains the above-mentioned compound 2 and the above-mentioned compound 7 and compound 15. The respective contents are shown in Table 4 below.

-Synthesis of infrared absorbing dye mixture powders 8 and 9-
In the same manner as for the infrared absorbing dye mixture powder 7, lots in which only the synthesis scale was changed were designated as infrared absorbing dye mixture powders 8 and 9. The composition of the mixture is shown in Table 4 below.

-Synthesis of infrared absorbing dye mixture powder 10 (for comparison)-
In addition, in the synthesis of the infrared absorbing dye mixture powder 7, all the “tap water” used was changed to “ion exchange water” and the synthesis lot was changed in the same manner except that the synthesis scale was changed. It was set to 10. The composition of the mixture is shown in Table 4 below.

-Preparation of printing ink-
An infrared-absorbing printing ink was prepared in exactly the same manner as in Example 1 except that the infrared-absorbing dye mixture powders 7 to 10 obtained above were used.
Using each of the obtained infrared absorbing printing inks, a barcode pattern was formed by gravure printing on plain paper MP-120 (made by Plus Co.) as a base paper.

  Next, on the barcode pattern formed as described above, in the same manner as in Example 1, three types of process inks having infrared transparency (FDOL yellow, FDOL magenta, FDOL cyan, Toyo Ink Manufacturing Co., Ltd.) )) Was applied by gravure printing to form a colored layer composed of three visible colors (indigo, red, yellow), thereby producing a printed matter in which a barcode pattern was arranged.

  In the obtained printed matter, the entire color layer of visible colors (indigo, red, yellow) is visible, but the barcode pattern is almost invisible, so the presence of the barcode pattern itself cannot be discerned with the naked eye Met.

  The printed matter was irradiated with two types of semiconductor laser light having a wavelength of 830 nm and a wavelength of 905 nm, and the emitted light having a wavelength of 950 nm or less was detected through a filter. At this time, the pattern formed with the infrared absorbing ink could be read.

  Subsequently, 70,000 lux of xenon light was continuously irradiated for 200 hours to the printed matter by a xenon lamp. Thereafter, the degree of reading of the barcode pattern after irradiation was evaluated. In the evaluation, a case where the PCS (print contrast signal) was 0.6 or more was rated as “good”, and a case where the PCS (print contrast signal) was less than 0.6 was rated as “bad”. . The evaluation results are shown in Table 5 below.

  As shown in Table 5, it is clear that the printed matter of the present invention has high light resistance of the barcode pattern in the printed matter.

The present invention can be applied to security-related fields such as authentication of characters and images, and fields where information is exchanged with marks such as symbols, dots, and barcodes. For example, for prevention of copying and provision of hidden information It is possible to use.

Claims (8)

The total content of the infrared absorbing dye selected from the group consisting of the infrared absorbing dye represented by the following general formula (2) or the following general formula (3), which contains the following (A) component and the following (B) component: An infrared absorbing composition having an amount of 50 ppm to 100,000 ppm.
(A) At least one selected from infrared absorbing dyes represented by the following general formula (1) (B) From the group consisting of infrared absorbing dyes represented by the following general formula (2) or the following general formula (3) At least one selected

[In General Formula (1), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. ]

[In General Formula (2), Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. ]


[In General Formula (3), M is a divalent atom including two atoms, a divalent metal atom, or a trivalent or tetravalent metal atom selected from the group consisting of a hydrogen atom and a monovalent metal atom. Represents a substituted metal atom. However, as said M, a copper atom is remove | excluded. Ar ₁ , Ar ₂ , Ar ₃ , Ar ₄ , Ar ₅ , Ar ₆ , Ar ₇ , and Ar ₈ each independently represent an aryl group. ]   2. The infrared absorptivity according to claim 1, wherein the total content of the infrared absorbing dye selected from the group consisting of the infrared absorbing dye represented by the general formula (2) or the general formula (3) is 100 ppm or more and 100,000 ppm or less. Composition.   Furthermore, the infrared absorptive composition of Claim 1 or Claim 2 containing an organic solvent.   The total content of the infrared absorbing dye selected from the group consisting of the infrared absorbing dye represented by the general formula (2) or the general formula (3) is that of the infrared absorbing dye represented by the general formula (1). It is 0.0001 times or more and 0.1 times or less with respect to content, The infrared absorptive composition of any one of Claims 1-3.   An infrared-absorbing ink containing the infrared-absorbing composition according to any one of claims 1 to 4.   A recorded matter having an image made of the infrared-absorbing ink according to claim 5 on a recording medium.   An image recording method comprising a step of forming an image by applying the infrared absorbing ink according to claim 5 on a recording medium. An image detection method comprising: detecting an image information of the image formed on the recording medium by an image recording method according to claim 7 using an infrared detector.