JP6234954B2 - Phthalocyanine compounds and near-infrared absorbing materials - Google Patents

Description

  The present invention relates to a phthalocyanine compound and a near-infrared absorbing material using the same.

  A compound having a phthalocyanine skeleton (phthalocyanine compound) has a blue to green taste and has been used as a dye / pigment for a long time. In addition, it is known that the absorption wavelength is shifted to the near infrared region by modifying the structure, and many phthalocyanine compounds that absorb near infrared rays have been proposed. For example, a compound such as naphthalocyanine having a longer absorption wavelength by expanding the ring, or a compound having a special metal such as palladium or vanadium as a central metal has been proposed (Patent Documents 1 to 3).

Japanese Patent No. 5288360 Japanese Patent No. 5046515 Japanese Patent No. 3565071

  However, there is still room for improvement in properties such as near-infrared absorptivity of phthalocyanine compounds proposed in Patent Documents 1 to 3. The present invention has been made in view of such problems of the prior art, and the subject is a phthalocyanine compound having a novel skeleton and excellent near-infrared absorption, and using the same, The object is to provide a near infrared absorbing material capable of forming a near infrared absorbing film and the like.

That is, according to the present invention, the following phthalocyanine compounds are provided.
[1] A phthalocyanine compound represented by the following general formula (1).

（前記一般式（１）中、Ｒ₁〜Ｒ₈は、それぞれ独立に、水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアルコキシ基、置換基を有してもよいアミノ基、又は置換基を有してもよいカルバゾリル基を示し、Ｒ ₁ とＲ ₂ 、Ｒ ₃ とＲ ₄ 、Ｒ ₅ とＲ ₆ 、及びＲ ₇ とＲ ₈ のうちの少なくとも１組が、置換基を有してもよいカルバゾリル基であり、Ｍは、２つの水素原子、又は２価、３価、若しくは４価の金属を示す）

(In the general formula (1), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, or a substituent. R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , and R ₇ and R ₈ . (At least one pair is a carbazolyl group which may have a substituent, and M represents two hydrogen atoms, or a divalent, trivalent, or tetravalent metal)

[2 ] In the general formula (1), at least two of R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , and R ₇ and R ₈ may have a substituent. The phthalocyanine compound according to the above [1], which is a good carbazolyl group.
[ 3 ] The phthalocyanine compound according to the above [1], wherein in the general formula (1), R _{1 to} R ₈ are all carbazolyl groups which may have a substituent.
[ 4 ] The phthalocyanine compound according to [1], in which, in the general formula (1), R _{1 to} R ₈ are all the same carbazolyl group which may have a substituent.

Moreover, according to this invention, the near-infrared absorption material shown below is provided.
[ 5 ] A near-infrared absorbing material containing a near-infrared absorbing pigment comprising the phthalocyanine compound according to any one of [1] to [ 4 ].

  The phthalocyanine compound of the present invention has a novel skeleton and is a compound excellent in near infrared absorption. Moreover, if the phthalocyanine compound of this invention is used, the near-infrared absorption material which can form a near-infrared absorption film | membrane etc. can be prepared.

It is a figure which shows the absorption wavelength spectrum of the dilute dispersion liquid of a phthalocyanine compound (A). It is a figure which shows the absorption wavelength spectrum of the dilute aqueous solution of a phthalocyanine compound (E).

  Embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments. The phthalocyanine compound of the present invention has a structure represented by the following general formula (1). Hereinafter, the details of the phthalocyanine compound of the present invention will be described.

（前記一般式（１）中、Ｒ₁〜Ｒ₈は、それぞれ独立に、水素原子、ハロゲン原子、置換基を有してもよいアルキル基、置換基を有してもよいアルコキシ基、置換基を有してもよいアミノ基、又は置換基を有してもよいカルバゾリル基を示し（但し、Ｒ₁〜Ｒ₈のうちの少なくとも１つは、置換基を有してもよいカルバゾリル基である）、Ｍは、２つの水素原子、又は２価、３価、若しくは４価の金属を示す）

(In the general formula (1), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, or a substituent. Or an optionally substituted amino group or an optionally substituted carbazolyl group (provided that at least one of R _{1 to} R ₈ is an optionally substituted carbazolyl group) ), M represents two hydrogen atoms, or a divalent, trivalent, or tetravalent metal)

  Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the alkyl group that may have a substituent include linear or branched alkyl groups having 1 to 20 carbon atoms. Examples of the alkoxy group which may have a substituent include an alkoxy group having 1 to 20 carbon atoms and containing one or more oxygen atoms. Moreover, as an amino group which may have a substituent, a C1-C20 amino group containing one or more nitrogen atoms can be mentioned.

  The central metal M is not particularly limited as long as it is a known divalent, trivalent, or tetravalent metal capable of forming a phthalocyanine skeleton. Specific examples of such metals include iron, magnesium, nickel, silicon, copper, zinc, aluminum, titanium, tin, and manganese. Note that a hydroxy group, an oxo group, or a halogen atom may be coordinated to the central metal M.

  The carbazolyl group is a group having a high electron donating property and also has good heat resistance, and thus is often used as a building block in the field of organic EL. For this reason, when a carbazolyl group is introduced into the peripheral position (β position) of phthalocyanine, the absorption wavelength is greatly shifted to become a phthalocyanine compound having near infrared absorptivity. Further, when a carbazolyl group is introduced into each adjacent peripheral position, the carbazole ring cannot exist on the same plane as the phthalocyanine ring due to its bulkiness, and is greatly distorted in the axial direction.

  For example, when the structure of the phthalocyanine compound (A) represented by the following formula is optimized using Gaussian 09 [* B3LYP / 6-311G (2d, p)], the carbazole ring is a carbazolyl group present on both sides. It can be seen that due to the steric hindrance to the phthalocyanine ring, it forms a dihedral angle of about 55 ° with the phthalocyanine ring. For this reason, the carbazolyl group forms a large steric hindrance not only in the parallel direction but also in the axial direction. This steric hindrance weakens the intermolecular interaction of the phthalocyanine compound and has a sharp absorption band. In addition, it has shown that the benzene ring containing the thick line in a following formula exists before paper space.

  Specific examples of the carbazolyl group which may have a substituent include a carbazolyl group, a 3-methylcarbazolyl group, a 3,6-dimethylcarbazolyl group, and a 3,6-di-t-butylcarbazolyl group. 3,6-dichlorocarbazolyl group, 3-fluorocarbazolyl group, 3-bromocarbazolyl group, 3,6-dibromocarbazolyl group, 3-iodocarbazolyl group, 3,6-di An iodocarbazolyl group, a 3,6-diphenylcarbazolyl group, a 4-hydroxycarbazolyl group, and the like can be given.

  Specific examples of the phthalocyanine compound of the present invention include compounds represented by the following formula.

In general formula (1), at least one of R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , and R ₇ and R ₈ is an optionally substituted carbazolyl group. Preferably, at least two of R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , and R ₇ and R ₈ are carbazolyl groups that may have a substituent. Is more preferable. Moreover, when R < ₁ > -R < ₈ > in General formula (1) is a carbazolyl group which may have a substituent, both a deep color effect and a steric hindrance become the maximum. Furthermore, when R _{1 to} R ₈ in the general formula (1) are the same carbazolyl group which may have a substituent, the symmetry is improved, and the stability of the compound is improved. As a further specific example of the phthalocyanine compound of the present invention, a compound represented by the following formula can be exemplified.

  The phthalocyanine compound represented by the general formula (1) can be synthesized, for example, by subjecting a compound represented by the following general formula (2) to a cyclization reaction with a metal salt of a central metal under a basic catalyst. . In addition, the number of carbazolyl groups in one molecule of the phthalocyanine compound represented by the general formula (1) obtained by the cyclization reaction is 8 at the maximum. If the compound represented by the following general formula (2) and a suitable phthalonitrile are mixed and subjected to a cyclization reaction, the number of carbazolyl groups in one molecule of the obtained phthalocyanine compound can be appropriately adjusted.

（前記一般式（２）中、Ｃｚ₁及びＣｚ₂は、それぞれ独立に、置換基を有してもよいカルバゾリル基を示す）

(In the general formula (2), Cz ₁ and Cz ₂ each independently represents a carbazolyl group which may have a substituent)

  The 3rd and 6th positions of the carbazolyl group are active for electrophilic reaction. Therefore, substitution of halogen atoms, nitro groups, sulfone groups, etc. at the 3rd and 6th positions of the carbazolyl group of the phthalocyanine compound (1) obtained by cyclization reaction by halogenation, nitration, sulfonation, etc. Groups can be introduced.

  A method for synthesizing a compound represented by the general formula (2), which is a synthetic intermediate, will be described with reference to a synthesis example of a compound represented by the following formula (3). The compound represented by the following formula (3) can be synthesized, for example, by reacting 4,5-difluorophthalonitrile and carbazole according to the method described in Japanese Patent No. 5366106. For this reason, the compound represented by General formula (2) is compoundable by selecting and reacting the carbazole which has a substituent suitably.

<Near-infrared absorbing material>
The near-infrared absorbing material of the present invention contains a near-infrared absorbing pigment made of the aforementioned phthalocyanine compound. The near-infrared absorbing material of the present invention can be used in a wide range of fields as a material for image display, image recording, printing ink, writing ink, plastic, pigment printing, and paint.

  The near-infrared absorbing material of the present invention usually contains a finely divided particulate near-infrared absorbing pigment made of the aforementioned phthalocyanine compound and a film-forming material. The amount of the phthalocyanine compound (near infrared absorbing pigment) in the near-infrared absorbing material is preferably 0.1 to 500 parts by mass and 1 to 100 parts by mass with respect to 100 parts by mass of the film-forming material. Further preferred. By setting the amount of the phthalocyanine compound in the above range, it is possible to form a film having better near-infrared absorption performance and having stronger strength. If the amount of the phthalocyanine compound is less than 0.1 part by mass, the near infrared absorption performance may be insufficient. On the other hand, when the amount of the phthalocyanine compound is more than 500 parts by mass, the strength of the formed film may be lowered and become brittle.

  The near-infrared absorbing material of the present invention is obtained by, for example, mixing the above-described refined near-infrared absorbing pigment made of the phthalocyanine compound and a film forming material such as a resin ((co) polymer), an oligomer, or a monomer. Can be prepared. The near-infrared absorbing material of the present invention can also be prepared by mixing a miniaturized near-infrared absorbing pigment and a coating liquid containing the above film-forming material. As the coating liquid containing a film-forming material, a coating liquid containing a photosensitive film-forming material or a coating liquid containing a non-photosensitive film-forming material can be used. Specific examples of the coating liquid containing a photosensitive film-forming material include a liquid containing a photosensitive film-forming material used for ultraviolet curable ink, electron beam curable ink, and the like. Specific examples of coating liquids containing non-photosensitive film-forming materials include varnishes used for printing inks such as letterpress inks, lithographic inks, gravure inks and screen inks; varnishes used for room temperature drying or baking paints Varnish used for electrodeposition coating; varnish used for thermal transfer ribbon, and the like.

  Specific examples of photosensitive film forming materials include photosensitive cyclized rubber resins, photosensitive phenol resins, photosensitive polyacrylate resins, photosensitive polyamide resins, photosensitive polyimide resins, and unsaturated polyester resins. And photosensitive resins such as polyester acrylate resins, polyepoxy acrylate resins, polyurethane acrylate resins, polyether acrylate resins, and polyol acrylate resins. Various monomers may be added as reactive diluents to the liquid containing these photosensitive resins.

  If a photopolymerization initiator such as benzoin ether or benzophenone is added to a near-infrared absorbing material containing a photosensitive resin as a film-forming material and kneaded by a conventionally known method, a photocurable near-infrared absorbing material is obtained. be able to. Moreover, if a thermal polymerization initiator is used instead of the photopolymerization initiator, a thermosetting near-infrared absorbing material can be obtained.

  Specific examples of non-photosensitive film-forming materials include styrene- (meth) acrylic ester copolymers, soluble polyamide resins, soluble polyimide resins, soluble polyamideimide resins, soluble polyesterimide resins, and water-soluble materials. Examples include aminopolyester resins, water-soluble salts thereof, water-soluble salts of styrene-maleic acid ester copolymers, and water-soluble salts of (meth) acrylic acid ester- (meth) acrylic acid copolymers. it can.

  The phthalocyanine compound (near infrared absorbing pigment) is preferably present as a single molecule in the near infrared absorbing material. Since the phthalocyanine compound is present as a single molecule, the phthalocyanine compound is uniformly arranged in the formed film, so that a film capable of absorbing near infrared rays more efficiently can be formed.

  Moreover, it is also preferable that the near-infrared absorbing pigment is present in the form of particles in the near-infrared absorbing material. When a general near-infrared absorbing dye exists in the form of particles, the absorption ability in the near-infrared region may decrease due to strong interaction between molecules. In contrast, in the phthalocyanine compound constituting the near-infrared absorbing pigment used in the near-infrared absorbing material of the present invention, the intermolecular interaction is adjusted by the carbazolyl group. For this reason, the near-infrared absorbing material of the present invention can efficiently absorb near-infrared light even if the near-infrared absorbing pigment is present in the form of particles, and is excellent in light resistance.

  The near-infrared absorbing pigment composed of a phthalocyanine compound has a diffusion coefficient equivalent diameter (distribution standard is light intensity) by a dynamic light scattering method of preferably 20 nm to 10 μm, and more preferably 50 nm to 1 μm. By making the equivalent diameter of the diffusion coefficient (distribution standard is light intensity) of the near-infrared absorbing pigment within the above range, it is possible to absorb near-infrared rays more efficiently and to form a film excellent in light resistance and smoothness. . When the near-infrared absorbing pigment has an equivalent diffusion coefficient diameter (distribution standard is light intensity) of less than 20 nm, near-infrared light can be efficiently absorbed, but light resistance is not improved so much. On the other hand, if the equivalent diameter of the diffusion coefficient of the near-infrared absorbing pigment (distribution standard is light intensity) is more than 10 μm, the near-infrared absorbing pigment tends to settle in the near-infrared absorbing material and can form a stable film. While becoming difficult, the smoothness of the formed film may be reduced.

  The particulate near-infrared absorbing pigment made of a phthalocyanine compound can be prepared, for example, by a general method for pigmentizing a dye. Specifically, (i) a method in which a solution obtained by dissolving a phthalocyanine compound in a solvent is diluted with a poor solvent to precipitate pigment particles; (ii) a solvent method in which the phthalocyanine compound is heated in the solvent; (iii) ) Solvent milling method.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In the examples and comparative examples, “parts” and “%” are based on mass unless otherwise specified.

<Synthesis of Intermediate>
(Synthesis of phthalonitrile (4))
With reference to the description in Japanese Patent No. 5366106, 4,5-difluorophthalonitrile and carbazole were reacted to synthesize a compound represented by the following formula (4) (phthalonitrile (4)).

<Synthesis of phthalocyanine compound>
Example 1
To 150 parts of ethyl cellosolve, 10 parts of phthalonitrile (3) represented by formula (3), 4 parts of diazabicycloundecene, and 1 part of copper (II) chloride were added and heated at 110 ° C. for 7 hours. After cooling, the mixture was filtered and washed with ethyl cellosolve, methanol, and water. It dried at 80 degreeC and obtained 8 parts of phthalocyanine compounds (A) represented by a following formula (A).

(Example 2)
7 parts of a phthalocyanine compound (B) represented by the following formula (B) was obtained in the same manner as in Example 1 except that 1 part of zinc chloride was used instead of 1 part of copper (II) chloride. .

(Example 3)
8 parts of a phthalocyanine compound (C) represented by the following formula (C) in the same manner as in Example 1 except that 14 parts of phthalonitrile (4) was used instead of 10 parts of phthalonitrile (3). Got.

Example 4
In the same manner as in Example 1 above, except that a mixture of 5 parts of phthalonitrile (3) and 7 parts of phthalonitrile (4) was used instead of 10 parts of phthalonitrile (3), 8 parts of the phthalocyanine compound (D) represented was obtained.

(Example 5)
To 150 parts of 98% sulfuric acid, 10 parts of a phthalocyanine compound (A) was added and stirred for 2 hours to obtain a sulfuric acid solution. The obtained sulfuric acid solution was diluted with water little by little, and sodium hydroxide was added to adjust the pH to 10-11. The precipitate formed after standing overnight was filtered and washed with dilute aqueous sodium hydroxide. It dried at 80 degreeC and 11 parts of phthalocyanine compounds (E) represented by a following formula (E) were obtained.

When the obtained compound was subjected to mass spectrometry (MALDI), peaks corresponding to the following molecular weights were detected. From the raw materials used and the results of mass spectrometry, it was confirmed that a phthalocyanine compound having the target composition was obtained.
Phthalocyanine compound (A): molecular weight 1895
Phthalocyanine compound (B): molecular weight 1896
Phthalocyanine compound (C): molecular weight 2439
Phthalocyanine compound (D): molecular weight 2173
Phthalocyanine compound (E): molecular weight 2306

<Evaluation>
Each component was mixed with the composition shown below and dispersed for 90 minutes using a paint shaker to prepare a dilute dispersion of the phthalocyanine compound (A) having a diffusion coefficient equivalent diameter of about 250 nm by a dynamic light scattering method. The absorption wavelength spectrum was measured using the diluted dispersion of the prepared phthalocyanine compound (A) as a measurement sample. The results are shown in FIG. Moreover, a dilute aqueous solution of the phthalocyanine compound (E) was prepared, and the absorption wavelength spectrum was measured. The results are shown in FIG.
-Phthalocyanine compound (A): 1.0 part-Water / 1-butanol (3/2 (mass ratio)) mixed solvent: 15.0 parts-Zirconia beads (diameter: 1 mmφ): 100 parts

Claims (5)

A phthalocyanine compound represented by the following general formula (1) .

(In the general formula (1), R _{1 to} R ₈ are each independently a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, or a substituent. R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , and R ₇ and R ₈ . (At least one pair is a carbazolyl group which may have a substituent, and M represents two hydrogen atoms, or a divalent, trivalent, or tetravalent metal) In the general formula (1), at least two of R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , and R ₇ and R ₈ may have a substituent. The phthalocyanine compound according to claim 1, wherein The phthalocyanine compound according to claim 1, wherein R _{1 to} R ₈ in the general formula (1) are all carbazolyl groups which may have a substituent. 2. The phthalocyanine compound according to claim 1, wherein in the general formula (1), R _{1 to} R ₈ are all the same carbazolyl group which may have a substituent. The near-infrared absorption material containing the near-infrared absorption pigment which consists of a phthalocyanine compound as described in any one of Claims 1-4 .

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