Anthraquinone Derivatives

Abstract

To provide an anthraquinone derivative that is usable as a cyan dye and also has superior light resistance.SOLUTION: An anthraquinone derivative is represented by the following formula (1-1). (In the formula, R1, R2, and R3 are an amino group or a hydroxyl group; at least one of Y1 and Y2 is an electron-donating group; in a case where only one of Y1 and Y2 is an electron-donating group, the other of Y1 and Y2 is H, a C1-C10 alkyl group, a C1-C10 alkoxy group, an aryl group, or a cyclohexyl group; Z is H, a C1-C10 alkyl group, a C1-C10 alkoxy group, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.)SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to anthraquinone derivatives. [Background technology]

[0002] Organic dyes are widely used in various printing inks and optical filters, and progress is being made in the development of organic dyes that can be used as dichroic dyes in liquid crystal devices and polarizing films. Among organic dyes, many anthraquinone derivatives, which are compounds having an anthraquinone skeleton, are highly stable and have excellent fastness against light, heat, temperature, etc. Therefore, among anthraquinone derivatives, compounds that can be used as dyes corresponding to the three primary colors have been extensively studied from the viewpoints of controlling absorption wavelength and coloring power, improving solubility in solvents and resins, and dichroism. For example, Patent Documents 1 and 2 describe anthraquinone derivatives that can be used as cyan dyes and have an absorption maximum wavelength in the wavelength range of 580 nm or more. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 63-90568 [Patent Document 2] Japanese Patent Publication No. 63-278994 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable for a dye to have good lightfastness, i.e., little fading due to light. As mentioned above, many anthraquinone derivatives have high fastness, but anthraquinone derivatives used as cyan dyes tend to have difficulty in achieving lightfastness. Therefore, there is a demand for anthraquinone derivatives that have an absorption maximum wavelength in the wavelength range of 580 nm or more and have good lightfastness. [Means for solving the problem]

[0005] Various aspects of anthraquinone derivatives for solving the above problems will be described below. [Aspect 1] An anthraquinone derivative represented by the following formula (1-1):

[0006] [ka]

[0007] In formula (1-1), R 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 and Y 2 At least one of Y is an electron donating group, 1 and Y 2 When only one of Y 1 and Y 2 The other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, or a cyclohexyl group, and the aryl group and cyclohexyl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

[0008] The above compound has an absorption maximum wavelength in the wavelength range of 600 nm or more, making it suitable for use as a cyan dye. Furthermore, the direct bonding of a phenyl group to the β-position of the anthraquinone skeleton enhances lightfastness. Furthermore, the electron-donating group at the para-position of the β-phenyl group in this structure enhances absorbance, resulting in high coloring strength.

[0009] [Aspect 2] The anthraquinone derivative according to [Aspect 1], represented by the following formula (1-2):

[0010] [ka]

[0011] In formula (1-2), Y 1 and Y 2 At least one of Y is an electron donating group, 1 and Y 2 When only one of Y 1 and Y 2 The other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, or a cyclohexyl group, and the aryl group and cyclohexyl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

[0012] [Aspect 3] The anthraquinone derivative according to [Aspect 1] or [Aspect 2], wherein the electron-donating group is an alkylamino group, an amino group, a piperidyl group, an acetamide group, or a hydroxyl group.

[0013] [Aspect 4] In the formula (1-2), Y 1 and Y 2 and each independently represent an alkylamino group, an amino group, or a piperidyl group.

[0014] [Aspect 5] An anthraquinone derivative represented by the following formula (2-1):

[0015] [ka]

[0016] In formula (2-1), R 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 and Y 2are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, an alkylamino group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. Z is an electron-withdrawing group.

[0017] The above compound has an absorption maximum wavelength in the wavelength range of 600 nm or more, making it suitable for use as a cyan dye. Furthermore, a substituted or unsubstituted phenyl group is directly bonded to the β-position of the anthraquinone skeleton, thereby enhancing lightfastness. Furthermore, the substituent at the para-position of the anilino group at the α-position in this structure is an electron-withdrawing group, thereby enhancing absorbance and achieving high coloring strength.

[0018] [Aspect 6] The anthraquinone derivative according to [Aspect 5], represented by the following formula (2-2):

[0019] [ka]

[0020] In formula (2-2), Y 1 and Y 2 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, an alkylamino group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. Z is an electron-withdrawing group.

[0021] [Aspect 7] The anthraquinone derivative according to [Aspect 5] or [Aspect 6], represented by the following formula (2-3):

[0022] [ka]

[0023] In formula (2-3), R 4 and R5 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group, and Z is an electron-withdrawing group.

[0024] [Aspect 8] The anthraquinone derivative according to any one of [Aspect 5] to [Aspect 7], wherein the electron-withdrawing group is a cyano group, an aldehyde group, an ester group, an acetyl group, a sulfo group, a nitro group, or a halogenated alkyl group.

[0025] [Aspect 9] An anthraquinone derivative represented by the following formula (3-1):

[0026] [ka]

[0027] In formula (3-1), R 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 and Y 2 at least one of Y is a cyclohexyl group, which may have a substituent; 1 and Y 2 When only one of Y is a cyclohexyl group, 1 and Y 2 the other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group, and the aryl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

[0028] The above compound has an absorption maximum wavelength in the wavelength region of 600 nm or more, making it suitable for use as a cyan dye. Furthermore, the direct bonding of a phenyl group to the β-position of the anthraquinone skeleton enhances lightfastness. Furthermore, the para-substituent of the β-phenyl group in this structure is a substituted or unsubstituted cyclohexyl group, suppressing absorption in the short wavelength region and providing an excellent blue hue.

[0029] [Aspect 10] The anthraquinone derivative according to [Aspect 9], represented by the following formula (3-2):

[0030] [ka]

[0031] In formula (3-2), Y 1 and Y 2 at least one of Y is a cyclohexyl group, which may have a substituent; 1 and Y 2 When only one of Y is a cyclohexyl group, 1 and Y 2 the other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group, and the aryl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

[0032] [Aspect 11] The anthraquinone derivative according to [Aspect 10], represented by the following formula (3-3):

[0033] [ka]

[0034] In formula (3-3), R 4 and R 5are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group, and Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

[0035] [Aspect 12] An anthraquinone derivative according to any one of [Aspect 1], [Aspect 5], and [Aspect 9], wherein the compound on the left side of the following reaction formula (4-2) represents the anthraquinone derivative, and the difference in total molecular energy between before and after the reaction shown in the following reaction formula (4-2), as determined by density functional theory, is −16 kcal / mol or more.

[0036] [ka]

[0037] [Aspect 13] An anthraquinone derivative according to any one of [Aspect 1], [Aspect 5], and [Aspect 9], having a 10% weight loss temperature of 350°C or higher.

[0038] [Aspect 14] An anthraquinone derivative according to any one of [Aspect 1], [Aspect 5], and [Aspect 9], wherein the magnitude of the transition dipole moment calculated by time-dependent density functional theory is 3.30 D or more and 5.00 D or less.

[0039] [Aspect 15] The anthraquinone derivative according to any one of [Aspect 1], [Aspect 5], and [Aspect 9], wherein the following formula (7-1) represents the anthraquinone derivative, and the molecular orbital coefficient of the highest occupied molecular orbital of the anthraquinone derivative calculated by density functional theory is C 11 , C 12 , C 21 , C 22 an anthraquinone derivative, wherein the square root of the sum of squares of coefficients corresponding to the orbitals on each carbon atom is calculated for each carbon atom, and the average value of the square roots of the sum of squares for each carbon atom is 0.03 or more and 0.2 or less.

[0040] [ka] [Effects of the Invention]

[0041] According to the present disclosure, it is possible to obtain good lightfastness for an anthraquinone derivative that can be used as a cyan dye. DETAILED DESCRIPTION OF THE INVENTION

[0042] Anthraquinone derivatives of first to seventh embodiments will be described below. In each embodiment, the anthraquinone derivative is a compound having a 9,10-anthraquinone skeleton. Regarding the substitution positions of the anthraquinone skeleton, the 1, 4, 5, and 8 positions are α positions, and the 2, 3, 6, and 7 positions are β positions.

[0043] The anthraquinone derivatives of each embodiment are used as dyes. The applications of the dyes are not particularly limited. For example, the anthraquinone derivatives can be used as dyes in inks for sublimation transfer printing and inkjet printing, toners for laser printers and copiers, optical filters such as color filters for liquid crystal displays and color separation filters used in camera tubes, and inks for anti-tamper printing. The anthraquinone derivatives can also be used as dichroic dyes in guest-host liquid crystal devices and polarizing films.

[0044] (First embodiment) The anthraquinone derivative of the first embodiment will be described below. The anthraquinone derivative of the first embodiment is a compound represented by the following formula (1-1).

[0045] [ka]

[0046] In formula (1-1), R 1 , R2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 and Y 2 At least one of Y is an electron donating group, 1 and Y 2 When only one of Y 1 and Y 2 The other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. The substituent is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group.

[0047] The electron-donating group is preferably an alkylamino group, an amino group, a piperidyl group, an acetamide group, or a hydroxyl group. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms. Y 1 and Y 2 When both of Y and Y are electron donating groups, 1 and Y 2 may be the same as or different from each other.

[0048] In formula (1-1), Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group. The halogen atom is preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms.

[0049] The function of the anthraquinone derivative of this embodiment will be described. The type of substituent in the anthraquinone skeleton affects the absorption wavelength of the anthraquinone derivative. The anthraquinone derivative of the first embodiment has a substituted or unsubstituted anilino group at the 1st position and amino groups or hydroxyl groups at the 4th, 5th, and 8th positions out of the four α-positions. Furthermore, the anthraquinone derivative has substituents at only two of the four β-positions, the 3rd and 7th positions, and these substituents are substituted or unsubstituted phenyl groups. Anthraquinone derivatives having such a structure have an absorption maximum wavelength in the wavelength range of 600 nm or more, and can therefore be used as cyan dyes.

[0050] Furthermore, one cause of photodegradation in anthraquinone derivatives is thought to be photoreduction in the anthraquinone skeleton, with the resin or the like present around the anthraquinone derivative acting as a hydrogen source. Conventional anthraquinone derivatives are known to have a structure in which a functional group such as a phenyl group is bonded to the β-position via an ether bond. In contrast, in the anthraquinone derivative of the present embodiment, a phenyl group is directly bonded to a carbon atom of the anthraquinone skeleton at the β-position. This structure inhibits the progress of the photoreduction reaction, resulting in high light resistance.

[0051] In detail, when a phenyl group is directly bonded to the β-position, the molecular structure is less likely to rotate at the bond at the β-position compared to when an ether bond is present at the β-position, and therefore the structure of the anthraquinone skeleton after photoreduction is less likely to become a stable structure, which is thought to suppress the progress of the photoreduction reaction.

[0052] Furthermore, it is desirable for the dye to have high tinting power, i.e., high absorbance. Higher tinting power allows for a reduction in the amount of dye used, which is beneficial from a cost perspective. It has been suggested that the greater the overlap between the molecular orbital distributions in the ground state and the excited state of an anthraquinone derivative, the higher the absorbance. Furthermore, the molecular orbital in the ground state is prone to change depending on the molecular structure, such as the substituent, and tends to be broader than the excited state. In contrast, the anthraquinone derivative of the first embodiment has a para-substituted phenyl group containing an electron-donating group at at least one β-position. The electron-donating group in the para-position of the phenyl group suppresses the broadening of the molecular orbital in the ground state, thereby increasing the extinction coefficient and, as a result, enhancing the tinting power of the anthraquinone derivative.

[0053] In the anthraquinone derivative of the first embodiment, the R 1 and R 3 is a hydroxyl group, and R 2 is preferably an amino group. Such a compound is represented by the following formula (1-2).

[0054] [ka]

[0055] In formula (1-2), Y 1 , Y 2 , and Z are defined as in formula (1-1). The anthraquinone derivative represented by formula (1-2) is easy to synthesize. Furthermore, the presence of a hydroxyl group at the α-position tends to cause the above-mentioned photoreduction, but the anthraquinone derivative of this embodiment suppresses the photoreduction reaction due to the structure in which a phenyl group is directly bonded to the β-position as described above. Therefore, it is possible to enjoy the advantages of a structure having a hydroxyl group at the α-position while eliminating the disadvantages of the structure.

[0056] Furthermore, in the anthraquinone derivative of the first embodiment, Y 1 and Y 2It is preferable that both of Y are electron donating groups. This enhances the controllability of the molecular orbital involved in the above-mentioned photoexcitation in the direction of increasing the absorption coefficient, thereby achieving higher coloring strength. In particular, Y 1 and Y 2 Each of the groups is preferably an alkylamino group, an amino group, or a piperidyl group. These functional groups have high electron donating properties, which allows for high control of the molecular orbitals involved in the photoexcitation described above. Therefore, higher coloring strength can be obtained.

[0057] Y 1 and Y 2 The compound in which each of Y is an alkylamino group or an amino group is represented by the following formula (1-3): 1 and Y 2 The compound in which each of the groups is a piperidyl group is represented by the following formula (1-4).

[0058] [ka]

[0059] In formula (1-3), Z is defined as in formula (1-1). 4 and R 5 are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms.

[0060] [ka]

[0061] In formula (1-4), Z is defined in the same way as in formula (1-1). The anthraquinone derivative of the first embodiment can be produced by introducing each substituent into the anthraquinone skeleton, for example, using 1,5-dihydroxy-4,8-dinitroanthraquinone or 1,5-diamino-4,8-dinitroanthraquinone as a starting material. A known method may be used to introduce the substituent. For example, the desired substituent can be introduced by reducing the nitro group, converting the substituent, brominating the β-position, or converting the bromo group.

[0062] (Second embodiment) The anthraquinone derivative of the second embodiment will be described below. The anthraquinone derivative of the second embodiment is a compound represented by the following formula (2-1).

[0063] [ka]

[0064] In formula (2-1), R 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 and Y 2 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, an alkylamino group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent.

[0065] The halogen atom is preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms. The substituent on the aryl group or cyclohexyl group is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group.

[0066] In formula (2-1), Z is an electron-withdrawing group. The electron-withdrawing group is preferably a cyano group, an aldehyde group, an ester group, an acetyl group, a sulfo group, a nitro group, or a halogenated alkyl group. The halogen contained in the halogenated alkyl group is preferably F, Cl, or Br. The number of carbon atoms contained in the halogenated alkyl group is preferably 1 to 10.

[0067] The anthraquinone derivative of the second embodiment has, among the four α-positions, a substituted anilino group at the 1-position and amino groups or hydroxyl groups at the 4-, 5-, and 8-positions. The anthraquinone derivative of the second embodiment also has two substituted or unsubstituted phenyl groups at the β-positions. Therefore, like the anthraquinone derivative of the first embodiment, the anthraquinone derivative of the second embodiment also has an absorption maximum wavelength in the wavelength range of 600 nm or more, and can therefore be used as a cyan dye.

[0068] In the anthraquinone derivative of the second embodiment, a phenyl group is directly bonded to a carbon atom constituting the anthraquinone skeleton at the β-position. This structure inhibits the progress of the photoreduction reaction, as in the first embodiment, and thus provides high light resistance.

[0069] Furthermore, the anthraquinone derivative of the second embodiment has a para-substituted anilino group containing an electron-withdrawing group at the α-position. The electron-withdrawing group in the para-substituted anilino group reduces the electron density of the aromatic ring of the anilino group, preventing the molecular orbital from spreading toward the anilino group. This also controls the molecular orbital involved in photoexcitation to increase the absorption coefficient, thereby enhancing the coloring power of the anthraquinone derivative.

[0070] In addition, when the anthraquinone derivative has a phenyl group at the β-position having an electron-donating group as a substituent at the para-position, as in the first embodiment, the effect of improving the coloring power is further enhanced.

[0071] In the anthraquinone derivative of the second embodiment, the R 1 and R 3is a hydroxyl group, and R 2 is preferably an amino group. Such a compound is represented by the following formula (2-2).

[0072] [ka]

[0073] In formula (2-2), Y 1 , Y 2 , and Z are defined as in formula (2-1). The anthraquinone derivative represented by formula (2-2) is easy to synthesize. Furthermore, the presence of a hydroxyl group at the α-position tends to cause the above-mentioned photoreduction, but the anthraquinone derivative of this embodiment suppresses the photoreduction reaction due to the structure in which a phenyl group is directly bonded to the β-position as described above. Therefore, it is possible to enjoy the advantages of a structure having a hydroxyl group at the α-position while eliminating the disadvantages of the structure.

[0074] Furthermore, the anthraquinone derivative of the second embodiment is preferably a compound represented by the following formula (2-3).

[0075] [ka]

[0076] In formula (2-3), Z is defined in the same way as in formula (2-1). 4 and R 5 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group. Many liquid crystal compounds have a cyclohexane ring, and phenylcyclohexane-based liquid crystals are also preferably used. Anthraquinone derivatives represented by formula (2-3) can be easily mixed with such liquid crystal materials, and therefore can be preferably used as dichroic dyes together with liquid crystal materials.

[0077] The anthraquinone derivative of the second embodiment can be produced by introducing each substituent into the anthraquinone skeleton, for example, using 1,5-dihydroxy-4,8-dinitroanthraquinone or 1,5-diamino-4,8-dinitroanthraquinone as a starting material. A known method may be used to introduce the substituent. For example, the desired substituent can be introduced by reducing the nitro group, converting the substituent, brominating the β-position, or converting the bromo group.

[0078] (Third embodiment) The anthraquinone derivative of the third embodiment will be described below. The anthraquinone derivative of the third embodiment is a compound represented by the following formula (3-1).

[0079] [ka]

[0080] In formula (3-1), R 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 and Y 2 At least one of the groups is a cyclohexyl group, and the cyclohexyl group may have a substituent. The substituent on the cyclohexyl group is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group.

[0081] Y 1 and Y 2 When only one of Y is a cyclohexyl group, 1 and Y 2The other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group, and the aryl group may have a substituent. The halogen atom is preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms. The substituent in the aryl group is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group.

[0082] In formula (3-1), Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group. The halogen atom is preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms.

[0083] In the anthraquinone derivative of the third embodiment, the substituent at the α-position is the same as in the first embodiment. Furthermore, the anthraquinone derivative of the third embodiment also has two substituted or unsubstituted phenyl groups at the β-position, similar to the first embodiment. Therefore, the anthraquinone derivative of the third embodiment also has an absorption maximum wavelength in the wavelength range of 600 nm or more, and can therefore be used as a cyan dye.

[0084] In the anthraquinone derivative of the third embodiment, a phenyl group is directly bonded to a carbon atom constituting the anthraquinone skeleton at the β-position. This structure inhibits the progress of the photoreduction reaction, as in the first and second embodiments, and thus provides high light resistance.

[0085] Furthermore, the anthraquinone derivative of the third embodiment has a para-substituted phenyl group at at least one β-position, and the para-substituent on the phenyl group is a substituted or unsubstituted cyclohexyl group. The para-substituent at the β-position allows for control of the molecular orbital involved in photoexcitation, and when the substituent is a cyclohexyl group, absorption in the short wavelength region shifts to the ultraviolet region. As a result, the blue component in the reflected light increases, resulting in a stronger blue tint as a dye. Having a strong blue tint is beneficial for cyan dyes used to correspond to the three primary colors. Therefore, the anthraquinone derivative of the third embodiment can be suitably used as a cyan dye.

[0086] In the anthraquinone derivative of the third embodiment, the R 1 and R 3 is a hydroxyl group, and R 2 is preferably an amino group. Such a compound is represented by the following formula (3-2).

[0087] [ka]

[0088] In formula (3-2), Y 1 , Y 2 , and Z are defined as in formula (3-1). The anthraquinone derivative represented by formula (3-2) is easy to synthesize. Furthermore, the presence of a hydroxyl group at the α-position tends to cause the above-mentioned photoreduction, but the anthraquinone derivative of this embodiment suppresses the photoreduction reaction due to the structure in which a phenyl group is directly bonded to the β-position as described above. Therefore, it is possible to enjoy the advantages of a structure having a hydroxyl group at the α-position while eliminating the disadvantages of the structure.

[0089] Furthermore, the anthraquinone derivative of the third embodiment is preferably a compound represented by the following formula (3-3).

[0090] [ka]

[0091] In formula (3-3), Z is defined as in formula (3-1). 4 and R 5 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group. In the anthraquinone derivative represented by formula (3-3), the para-substituents of the two β-positioned phenyl groups are both substituted or unsubstituted cyclohexyl groups. This results in a greater effect of suppressing absorption in the short wavelength region, resulting in a stronger blue color. As in the second embodiment, when the anthraquinone derivative has an anilino group at the α-position and an electron-withdrawing group as a substituent at the para-position, the effect of improving coloring power can be obtained.

[0092] The anthraquinone derivative of the third embodiment can be produced by introducing each substituent into the anthraquinone skeleton, for example, using 1,5-dihydroxy-4,8-dinitroanthraquinone or 1,5-diamino-4,8-dinitroanthraquinone as a starting material. The introduction of the substituent can be performed using a known method. For example, the desired substituent can be introduced by reducing the nitro group, converting the substituent, brominating the β-position, or converting the bromo group.

[0093] (Fourth embodiment) An anthraquinone derivative according to a fourth embodiment will be described. The anthraquinone derivative according to the fourth embodiment is a compound represented by the following formula (4-1), in which the total energy difference ΔE before and after the reaction represented by the following reaction formula (4-2) is -16 kcal / mol or more.

[0094] [ka]

[0095] [ka]

[0096] In formula (4-1), X is -NH- or a sulfur atom. 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 , and ,A. 2 are each independently a direct bond, an oxygen atom, a sulfur atom, or -NH-. 1 ,A 2 is a direct bond means that a substituted or unsubstituted phenyl group is directly bonded to a carbon atom constituting the anthraquinone skeleton at the β-position of the anthraquinone derivative.

[0097] In formula (4-1), Y 1 , Y 2 and Z are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, a halogenated alkyl group having 1 to 10 carbon atoms, an amino group, an alkylamino group, a piperidyl group, an aryl group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. The substituent is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group. The halogen atom and the halogen atom contained in the halogenated alkyl group are preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms.

[0098] The above reaction formula (4-2) shows the photoreduction reaction of the anthraquinone derivative represented by the above formula (4-1). In this reaction, photoreduction of the anthraquinone derivative P4 occurs using a resin or the like present around the anthraquinone derivative P4 as a hydrogen source, and a hydrogen adduct K4, which is a compound in which hydrogen is added to the anthraquinone skeleton, is produced.

[0099] The total energy difference ΔE is the value obtained by subtracting the total energy Ep of the anthraquinone derivative P4 from the total energy Ek of the hydrogen adduct K4 (ΔE=Ek−Ep). The energies Ep and Ek of the anthraquinone derivative P4 and the hydrogen adduct K4 are calculated by quantum chemical calculations using density functional theory (DFT). The functional used is B3LYP, and the basis set is 6-31G(d). These quantum chemical calculations can be performed using general-purpose quantum chemical calculation programs such as Gaussian and GAMESS. The energies Ep and Ek are the total energies of the molecules in the optimized structure obtained by the quantum chemical calculations.

[0100] The effect of the anthraquinone derivative of the fourth embodiment will be described. The anthraquinone derivative having a substituent as in the above formula (4-1) has a maximum absorption wavelength in the wavelength range of 580 nm or more and 830 nm or less, and therefore can be used as a cyan dye.

[0101] In the anthraquinone derivative of the fourth embodiment, the total energy difference ΔE is -16 kcal / mol or more. One cause of deterioration of anthraquinone derivatives due to light is the reaction shown in the above reaction formula (4-2). The larger the total energy difference ΔE, the less likely the above reaction occurs. If the total energy difference ΔE is -16 kcal / mol or more, good light resistance can be obtained. Furthermore, in order to obtain even higher light resistance, the total energy difference ΔE is preferably -14 kcal / mol or more.

[0102] In the fourth embodiment, a first example of a suitable anthraquinone derivative is, among the above-mentioned compounds represented by the above formula (4-1), R 1 , R 2 , and ,R 3 In such a compound, the total energy difference ΔE is larger, resulting in high light resistance. If an anthraquinone derivative has a hydroxyl group at the α-position, it is thought that photoreduction reactions are more likely to occur. 1 , R2 , and ,R 3 It is believed that deterioration due to photoreduction reactions can be effectively suppressed by the fact that all of the groups are amino groups.

[0103] In the fourth embodiment, a second example of a suitable anthraquinone derivative is, among the above-mentioned compounds represented by the above formula (4-1), R 1 and R 3 is a hydroxyl group, and R 2 is an amino group, and A 1 ,A 2 is a compound in which the phenyl group is directly bonded to the β-position. Such a compound has a larger total energy difference ΔE, and therefore high light resistance. In such a structure, as described in the first embodiment, the phenyl group is directly bonded to the β-position, and it is thought that the three-dimensional structure of the molecule effectively suppresses deterioration due to photoreduction reactions.

[0104] The anthraquinone derivative of the fourth embodiment may be any of the compounds described in the first to third embodiments, as long as the total energy difference ΔE is -16 kcal / mol or more. Even if the compound is different from the compound represented by formula (4-1) among the compounds described in the first to third embodiments, good light resistance can be obtained as long as the total energy difference ΔE is -16 kcal / mol or more.

[0105] (Fifth embodiment) An anthraquinone derivative according to the fifth embodiment will be described. The anthraquinone derivative according to the fifth embodiment is a compound represented by the following formula (5-1), and has a 10% weight loss temperature of 350° C. or higher in thermogravimetry.

[0106] [ka]

[0107] In formula (5-1), X is -NH- or a sulfur atom. 1 , R 2 , and ,R 3are each independently an amino group or a hydroxyl group. 1 , and ,A. 2 are each independently a direct bond, an oxygen atom, a sulfur atom, or -NH-. 1 ,A 2 is a direct bond means that a substituted or unsubstituted phenyl group is directly bonded to a carbon atom constituting the anthraquinone skeleton at the β-position of the anthraquinone derivative.

[0108] In equation (5-1), Y 1 , Y 2 and Z are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, a halogenated alkyl group having 1 to 10 carbon atoms, an amino group, an alkylamino group, a piperidyl group, an aryl group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. The substituent is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group. The halogen atom and the halogen atom contained in the halogenated alkyl group are preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms.

[0109] The thermogravimetric measurement is carried out under the conditions of a gas flow rate of 200 mL / min and a temperature rise rate of 10°C / min. Air is used as the gas. The effect of the anthraquinone derivative of the fifth embodiment will be described. The anthraquinone derivative having a substituent as in the above formula (5-1) has a maximum absorption wavelength in the wavelength range of 580 nm or more and 830 nm or less, and therefore can be used as a cyan dye.

[0110] The anthraquinone derivative of the fifth embodiment has a 10% weight loss temperature of 350°C or higher in the thermogravimetric measurement. When high heat is applied to an anthraquinone derivative, the anthraquinone derivative decomposes to generate radicals, which further promote decomposition and other reactions. Since one cause of photodegradation of an anthraquinone derivative is radicals generated from the surroundings or itself, anthraquinone derivatives that are less susceptible to thermal decomposition, i.e., anthraquinone derivatives with a high 10% weight loss temperature, tend to have high light resistance. If the 10% weight loss temperature is 350°C or higher, good light resistance can be obtained. Furthermore, to obtain even higher light resistance, it is preferable that the 10% weight loss temperature be 365°C or higher.

[0111] In the fifth embodiment, a first example of a suitable anthraquinone derivative is, among the above-mentioned compounds represented by the above formula (5-1), R 2 is an amino group. Such compounds are easy to synthesize.

[0112] In the fifth embodiment, a second example of a suitable anthraquinone derivative is a compound represented by the formula (5-1) above, wherein R 1 and R 3 is a hydroxyl group, and R 2 is an amino group. Such compounds are easy to synthesize.

[0113] In the fifth embodiment, a third example of a suitable anthraquinone derivative is a compound represented by the formula (5-1) above, wherein R 1 , R 2 , and ,R 3 Each of the groups is an amino group. Such compounds have a higher 10% weight loss temperature and therefore high light resistance.

[0114] In the fifth embodiment, a fourth example of a suitable anthraquinone derivative is a compound represented by the formula (5-1) above, wherein R 2 is an amino group, and A 1 and A 2In such compounds, the 10% weight loss temperature is higher, and therefore high light resistance is obtained.

[0115] The anthraquinone derivative of the fifth embodiment may be any of the compounds described in the first to third embodiments, provided that it has a 10% weight loss temperature of 350° C. or higher. Even if the compound is different from the compound represented by formula (5-1) among the compounds described in the first to third embodiments, it can obtain good light resistance by having a 10% weight loss temperature of 350° C. or higher.

[0116] (Sixth embodiment) It is desirable for a dye to have high coloring power, i.e., high absorbance. The coloring power of an anthraquinone derivative varies depending on the type and position of the substituents that the anthraquinone derivative has. Since there are many options for substituents that can be introduced into anthraquinone derivatives, the coloring power of anthraquinone derivatives varies greatly, and many conventional anthraquinone derivatives have low coloring power.

[0117] The higher the coloring strength, the more the amount of pigment can be reduced, which is beneficial from the viewpoint of cost. Furthermore, since anthraquinone derivatives have high molecular planarity and it is difficult to increase solubility, there is a limit to how much the color can be strengthened by increasing the amount. Therefore, improving coloring strength is an important issue. The anthraquinone derivative of the sixth embodiment aims to improve coloring strength.

[0118] An anthraquinone derivative according to the sixth embodiment will be described. In the anthraquinone derivative according to the sixth embodiment, the magnitude of the transition dipole moment calculated by the time dependent density functional theory (TDDFT) is 3.30D or more and 5.00D or less.

[0119] The transition dipole moment of an anthraquinone derivative is the electric dipole moment that occurs during the electron transition in vacuum associated with the absorption. The transition dipole moment is calculated using the B3LYP functional and the 6-31G(d) basis set. Such quantum chemistry calculations can be performed using general-purpose quantum chemistry calculation programs such as Gaussian and GAMESS.

[0120] Since the molar extinction coefficient is proportional to the square of the transition dipole moment, the larger the transition dipole moment, the higher the absorbance tends to be. If the transition dipole moment is 3.30D or greater, sufficient absorbance is obtained, resulting in good coloring strength.

[0121] The type and position of the substituents on the anthraquinone derivative affect not only the magnitude of the transition dipole moment but also the maximum absorption wavelength. If the magnitude of the transition dipole moment is 3.30 D or more, both the absorbance and the maximum absorption wavelength can be obtained satisfactorily.

[0122] Furthermore, if the magnitude of the transition dipole moment is 5.00 D or less, the arrangement and structure of the substituents are prevented from becoming complicated, making synthesis easier. The anthraquinone derivative of the sixth embodiment is preferably a compound represented by the following formula (6-1).

[0123] [ka]

[0124] In formula (6-1), X is -NH- or a sulfur atom. 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group.

[0125] In equation (6-1), Y 1 , Y 2and Z are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, a halogenated alkyl group having 1 to 10 carbon atoms, an amino group, an alkylamino group, a piperidyl group, an aryl group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. The substituent is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group. The halogen atom and the halogen atom contained in the halogenated alkyl group are preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms.

[0126] Anthraquinone derivatives with a substituent, such as those in formula (6-1), can increase the transition dipole moment and enhance the maximum absorption wavelength. Specifically, the maximum absorption wavelength is in the wavelength range of 580 nm to 830 nm. Therefore, they can be used as cyan dyes with high coloring power. Furthermore, since a phenyl group is directly bonded to the β-position, good lightfastness can be achieved.

[0127] Among the compounds represented by the above formula (6-1), a first example of a suitable anthraquinone derivative is R 1 and R 3 is a hydroxyl group, and R 2 is an amino group. Such compounds are easy to synthesize.

[0128] Among the compounds represented by the above formula (6-1), a second example of a suitable anthraquinone derivative is R 2is an amino group and X is a sulfur atom. These compounds have both an amino group or hydroxyl group at the α-position and a phenyl group directly bonded to the β-position, which contributes significantly to the long-wavelength shift of the absorption maximum wavelength, and a phenylthio group at the α-position, which contributes less to the long-wavelength shift of the absorption maximum wavelength. This allows for an absorption maximum wavelength of 580 nm or more, which is usable as a cyan dye, while preventing the absorption maximum wavelength from becoming too large. Specifically, it is possible to achieve an absorption maximum wavelength in the range of 580 nm to 670 nm. This results in an excellent blue hue.

[0129] The anthraquinone derivative of the sixth embodiment may be the anthraquinone derivative of the first embodiment. Such a compound can provide high lightfastness and also enhance coloring power due to the action of the para-substituted phenyl group having an electron-donating group at the β-position.

[0130] The anthraquinone derivative of the sixth embodiment may be the anthraquinone derivative of the second embodiment. Such a compound can provide high lightfastness and also enhance coloring power due to the action of the para-substituted anilino group having an electron-withdrawing group at the α-position.

[0131] The anthraquinone derivative of the sixth embodiment may be the anthraquinone derivative of the third embodiment. Such a compound can provide high lightfastness and also provide a strong blue tint due to the action of the para-substituted phenyl group having a cyclohexyl group at the β-position.

[0132] (Seventh embodiment) The anthraquinone derivative of the seventh embodiment aims to improve coloring power, similarly to the sixth embodiment.

[0133] An anthraquinone derivative according to the seventh embodiment will be described. The anthraquinone derivative according to the seventh embodiment is a compound represented by the following formula (7-1), and satisfies the conditions for molecular orbital coefficients described below.

[0134] [ka]

[0135] In formula (7-1), C 11 , C 12 , C 21 , C 22 Each of R is a carbon atom. In formula (7-1), X is -NH- or a sulfur atom. In formula (7-1), R 1 , R 2 , and ,R 3 are each independently an amino group or a hydroxyl group. 1 , and ,A. 2 are each independently a direct bond, an oxygen atom, a sulfur atom, or -NH-. 1 ,A 2 is a direct bond means that a substituted or unsubstituted phenyl group is directly bonded to a carbon atom constituting the anthraquinone skeleton at the β-position of the anthraquinone derivative.

[0136] In equation (7-1), Y 1 , Y 2 and Z are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, a halogenated alkyl group having 1 to 10 carbon atoms, an amino group, an alkylamino group, a piperidyl group, an aryl group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. The substituent is preferably an alkyl group having 1 to 10 carbon atoms or a cyclic hydrocarbon group. The cyclic hydrocarbon group is preferably a cyclohexyl group or a phenyl group. The halogen atom and the halogen atom contained in the halogenated alkyl group are preferably F, Cl, or Br. The alkylamino group may have one or two alkyl groups. The alkyl group in the alkylamino group preferably has 1 to 10 carbon atoms.

[0137] In the anthraquinone derivative of the seventh embodiment, the molecular orbital coefficient of the highest occupied molecular orbital (HOMO) obtained by quantum chemical calculation using density functional theory (DFT) is C 11 , C 12 , C 21 , C 22 The average Mv of the square root of the sum of the squares of the coefficients corresponding to the orbitals on each carbon atom is between 0.03 and 0.2. The functional used is B3LYP, and the basis set is 6-31G(d).

[0138] That is, C 11 The square root of the sum of the squares of the molecular orbital coefficients for M 11 and C 12 The square root of the sum of the squares of the molecular orbital coefficients for M 12 and C 21 The square root of the sum of the squares of the molecular orbital coefficients for M 21 and C 22 The square root of the sum of the squares of the molecular orbital coefficients for M 22 In this case, M 11 , M 12 , M 21 , M 22 The average value of these is the average Mv.

[0139] The quantum chemical calculations can be performed using a general-purpose quantum chemical calculation program such as Gaussian or GAMESS.

[0140] The effect of the anthraquinone derivative of the seventh embodiment will be described. The anthraquinone derivative having a substituent as in the above formula (7-1) has a maximum absorption wavelength in the wavelength range of 580 nm or more and 830 nm or less, and therefore can be used as a cyan dye.

[0141] Generally, the electronic transition that shows the absorption maximum is the electronic transition from HOMO to LUMO. It is thought that the greater the overlap between the molecular orbitals of the HOMO and LUMO, the higher the probability of electronic transition, resulting in high absorbance. After extensive research, the inventors discovered a tendency for the molecular orbitals of the HOMO and LUMO to spread in anthraquinone derivatives.

[0142] In other words, the type and arrangement of the substituents have little effect on the LUMO molecular orbital of anthraquinone derivatives, and the LUMO molecular orbital tends to cluster around the anthraquinone skeleton. On the other hand, the HOMO molecular orbital varies greatly depending on the type and arrangement of the substituents. In the structure represented by the above formula (7-1), the HOMO molecular orbital tends to spread toward the α-position where the anilino group or phenylthio group is bonded, that is, toward the substituent containing X.

[0143] Therefore, if the HOMO molecular orbital is configured to extend toward the β-position substituent, that is, to extend over the benzene ring contained in the β-position substituent, it is thought that the HOMO molecular orbital will be prevented from extending too far toward the α-position and will extend in a balanced manner around the anthraquinone skeleton, resulting in a greater overlap between the HOMO and LUMO molecular orbitals.

[0144] The extent to which the HOMO molecular orbital extends over the β-position of the benzene ring can be expressed by the coefficient of the orbital on the carbon atom contained in the benzene ring. In other words, the larger the average Mv, the greater the extent to which the molecular orbital extends over the β-position of the benzene ring. If the average Mv is 0.03 or greater, the overlap between the HOMO and LUMO molecular orbitals is large enough to obtain good absorbance at the absorption maximum wavelength, resulting in high coloring strength. On the other hand, if the average Mv is 0.2 or less, the arrangement and structure of the substituents are prevented from becoming complex, facilitating the synthesis of anthraquinone derivatives. Furthermore, the HOMO molecular orbital is prevented from extending too far toward the β-position of the substituent, thereby reducing the overlap between the HOMO and LUMO molecular orbitals.

[0145] In the seventh embodiment, a first example of a suitable anthraquinone derivative is, among the above-mentioned compounds represented by the above formula (7-1), R 1 and R 3 is a hydroxyl group, and R 2 is an amino group. Such compounds are easy to synthesize.

[0146] In the seventh embodiment, a second example of a suitable anthraquinone derivative is, among the above-mentioned compounds represented by the above formula (7-1), R 1 and R 3 is a hydroxyl group, and R 2 is an amino group, and A 1 and A 2 These compounds are anthraquinone derivatives in which the bond is direct. These compounds are easy to synthesize and have high light resistance. They also have a high average Mv.

[0147] The anthraquinone derivative of the seventh embodiment may be any of the compounds described in the first to third embodiments, so long as it has an average Mv of 0.03 or more and 0.2 or less. Even if the compound is different from the compound represented by formula (7-1) among the compounds described in the first to third embodiments, good coloring power can be obtained by having an average Mv of 0.03 or more and 0.2 or less.

[0148] In an anthraquinone derivative, in order to increase the average Mv within the range of 0.03 to 0.2, it is preferable that a substituted or unsubstituted phenyl group be directly bonded to the β-position. Similarly, in order to increase the average Mv within the above range, it is preferable that the anthraquinone derivative has a para-substituted phenyl group at the β-position, and the substituent at the para-position of the phenyl group is an electron-donating group. That is, the anthraquinone derivative of the first embodiment can obtain good tinting strength. Similarly, in order to increase the average Mv within the above range, it is preferable that the anthraquinone derivative has a para-substituted anilino group at the α-position, and the substituent at the para-position of the anilino group is an electron-withdrawing group. That is, the anthraquinone derivative of the second embodiment can obtain good tinting strength.

[0149] [Example] The above-mentioned anthraquinone derivatives will be described using specific examples. Note that the weight parts of each material below indicate the relative weight ratios of the materials mixed together.

[0150] [First Example: Test Example Corresponding to the First Embodiment] (Test Examples 1-1 to 1-13) <Synthesis of precursor A1> 1,5-Dihydroxy-4,8-dinitroanthraquinone (5.0 parts by weight) and N,N-dimethylformamide (100 parts by weight) were added to a two-necked recovery flask. N-Bromosuccinimide (5.9 parts by weight) was added to the mixture at room temperature and stirred for 1 hour. After confirming the completion of the reaction by thin layer chromatography, the reaction solution was added to a sufficient amount of methanol and stirred for 15 minutes. The precipitated solid was then collected by suction filtration and vacuum dried at 60°C overnight to obtain Precursor A1 as a yellow solid. Precursor A1 is a compound represented by the following formula (1-a):

[0151] [ka]

[0152] <Synthesis of precursor A2> Precursor A1 (1.0 parts by weight) and N-methyl-2-pyrrolidone (20 parts by weight) were added to a two-necked recovery flask. 4-Heptylaniline (0.8 parts by weight) was added and the mixture was heated and stirred in an oil bath at 180°C. After confirming the completion of the reaction by thin-layer chromatography, the reaction solution was allowed to cool to room temperature. Ethyl acetate (30 parts by weight) and water (10 parts by weight) were added and the mixture was vigorously stirred at room temperature. Insoluble matter formed during this process was removed by filtration through Celite. After separating the two layers, the organic layer was washed sequentially with distilled water, 5% aqueous hydrochloric acid, and saturated saline, and then dried over anhydrous magnesium sulfate. The desiccant was then filtered off, and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (developing solvent: hexane / dichloromethane = 2 / 1 to 2 / 3), and the resulting solid was dried in vacuo to obtain Precursor A2 as a dark blue solid. Precursor A2 is a compound represented by the following formula (1-b):

[0153] [ka]

[0154] <Synthesis of precursor A3> Precursor A3 was obtained in the same manner as in the synthesis of Precursor A2, except that 4-heptylaniline was replaced with 4-heptyloxyaniline. Precursor A3 is a compound represented by the following formula (1-c).

[0155] [ka]

[0156] <Synthesis of dye of Test Example 1-1> Toluene (5 parts by weight), water (2.5 parts by weight), Precursor A2 (0.30 parts by weight, 1 equivalent), 4-dimethylaminophenylboronic acid (0.28 parts by weight, 2.4 equivalents), potassium carbonate (0.21 parts by weight) as a base, and tetrakistriphenylphosphine palladium (0.06 parts by weight) as a catalyst were placed in a recovery flask equipped with a Dimroth condenser and purged with nitrogen. The mixture was heated and stirred at 80°C for 2 hours. After confirming the completion of the reaction by thin-layer chromatography, the reaction solution was returned to room temperature, purified water was added, and extraction with ethyl acetate was performed. Sodium sulfate was added to the resulting organic layer, which was then dried. The solvent was then removed under reduced pressure using an evaporator. The resulting residue was purified by column chromatography (developing solvent: hexane / ethyl acetate = 10 / 1 to 5 / 1) to obtain the anthraquinone derivative of Test Example 1-1. The anthraquinone derivative of Test Example 1-1 is a compound represented by the following formula (P1-1).

[0157] [ka]

[0158] <Synthesis of dye in Test Example 1-2> The anthraquinone derivative of Test Example 1-2 was obtained by the same synthesis as in Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with 4-dibutylaminophenylboronic acid. The anthraquinone derivative of Test Example 1-2 is a compound represented by the following formula (P1-2).

[0159] [ka]

[0160] <Synthesis of dyes in Test Examples 1-3> The anthraquinone derivative of Test Example 1-3 was obtained in the same manner as in the dye synthesis process of Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with 4-monobutylaminophenylboronic acid. The anthraquinone derivative of Test Example 1-3 is a compound represented by the following formula (P1-3).

[0161] [ka]

[0162] <Synthesis of dyes in Test Examples 1-4> The anthraquinone derivative of Test Example 1-4 was obtained by the same synthesis as in Test Example 1-1, except that in the synthesis process of the dye in Test Example 1-1, precursor A2 was changed to precursor A3 and 4-dimethylaminophenylboronic acid was changed to 4-monobutylaminophenylboronic acid. The anthraquinone derivative of Test Example 1-4 is a compound represented by the following formula (P1-4).

[0163] [ka]

[0164] <Synthesis of dyes in Test Examples 1-5> The anthraquinone derivative of Test Example 1-5 was obtained by the same synthesis as in the dye synthesis process of Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with (4-piperidin-1-yl)phenylboronic acid. The anthraquinone derivative of Test Example 1-5 is a compound represented by the following formula (P1-5).

[0165] [ka]

[0166] <Synthesis of dyes in Test Examples 1-6> The anthraquinone derivative of Test Example 1-6 was obtained by the same synthesis as in Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with 4-aminophenylboronic acid. The anthraquinone derivative of Test Example 1-6 is a compound represented by the following formula (P1-6).

[0167] [ka]

[0168] <Synthesis of dyes in Test Examples 1-7> The anthraquinone derivative of Test Example 1-7 was obtained by the same synthesis as in the dye synthesis process of Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with 4-acetamidophenylboronic acid. The anthraquinone derivative of Test Example 1-7 is a compound represented by the following formula (P1-7).

[0169] [ka]

[0170] <Synthesis of dyes in Test Examples 1-8> The anthraquinone derivative of Test Example 1-8 was obtained by the same synthesis as in the dye synthesis process of Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with 4-hydroxyphenylboronic acid. The anthraquinone derivative of Test Example 1-8 is a compound represented by the following formula (P1-8).

[0171] [ka]

[0172] <Synthesis of dyes in Test Examples 1-9> In the synthesis process of the dye of Test Example 1-1 above, precursor A2 was changed to precursor A3, and 1.2 equivalents of 4-monobutylaminophenylboronic acid was added instead of 4-dimethylaminophenylboronic acid, and the reaction solution was stirred at 80°C for 1 hour. After that, 1.2 equivalents of 4-heptylphenylboronic acid was added, and the mixture was heated and stirred at 80°C for 2 hours or more. Thereafter, extraction and purification were carried out in the same manner as in the synthesis process of the dye of Test Example 1-1 above, and an anthraquinone derivative of Test Example 1-9 was obtained. The anthraquinone derivative of Test Example 1-9 is a compound represented by the following formula (P1-9).

[0173] [ka]

[0174] <Synthesis of dyes in Test Examples 1-10> The anthraquinone derivative of Test Example 1-10 was obtained by the same synthesis as in the dye synthesis process of Test Example 1-1, except that 4-dimethylaminophenylboronic acid was replaced with 4-heptyloxyphenylboronic acid. The anthraquinone derivative of Test Example 1-10 is a compound represented by the following formula (P1-10).

[0175] [ka]

[0176] <Synthesis of dyes in Test Examples 1-11> The anthraquinone derivative of Test Example 1-11 was obtained by the same synthesis procedure as in Test Example 1-1, except that precursor A2 was replaced with precursor A3 and 4-dimethylaminophenylboronic acid was replaced with 4-heptyloxyphenylboronic acid. The anthraquinone derivative of Test Example 1-11 is a compound represented by the following formula (P1-11).

[0177] [ka]

[0178] <Synthesis of dyes in Test Examples 1-12> A two-necked recovery flask was charged with 4-heptyloxyphenol (8.65 parts by weight) and N-methyl-2-pyrrolidone (100 parts by weight). Sodium hydride (55%, 1.7 parts by weight) was gently added in five portions and stirred in a 60°C oil bath for 3 hours. Precursor A3 (5.00 parts by weight) was added to this solution, and the mixture was heated and stirred in a 130°C oil bath for 24 hours. After confirming the completion of the reaction by thin-layer chromatography, the reaction solution was returned to room temperature, ethyl acetate and distilled water were added, and the mixture was vigorously stirred at room temperature. After separating the two layers, the organic layer was washed sequentially with distilled water and saturated brine, and then dried over anhydrous magnesium sulfate. The desiccant was then filtered off, and the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (developing solvent: hexane / dichloromethane = 1 / 1 to 1 / 2). The resulting solid was washed with ethanol and dried in vacuo at 60°C to obtain the anthraquinone derivative of Test Example 1-12. The anthraquinone derivative of Test Example 1-12 is a compound represented by the following formula (P1-12).

[0179] [ka]

[0180] <Synthesis of dyes in Test Examples 1-13> The anthraquinone derivative of Test Example 1-13 was obtained by the same synthesis as in Test Example 1-12, except that in the synthesis process of the dye, 4-heptyloxyphenol (8.65 parts by weight) was changed to 4-butylaminophenol (6.86 parts by weight) and precursor A3 was changed to precursor A2. The anthraquinone derivative of Test Example 1-13 is a compound represented by the following formula (P1-13).

[0181] [ka]

[0182] (Test Examples 1-14 and 1-15) <Synthesis of precursor B1> A two-neck flask was charged with 1,5-diaminoanthraquinone (5.0 parts by weight), N,N-dimethylformamide (397 parts by weight), and pyridine (10.3 parts by weight), and the inside of the flask was purged with nitrogen. The solution was thoroughly cooled in an ice bath, and acetyl chloride (19.8 parts by weight) was added dropwise to the solution over 45 minutes while cooling with ice. The solution was then stirred for 10 minutes while cooling with ice, and then stirred at room temperature for 24 hours. The precipitate was then collected by suction filtration, washed with diethyl ether, and dried to obtain a brown crude product. The crude product (5.5 parts by weight) and ethyl acetate (54 parts by weight) were then placed in a recovery flask, heated to reflux, and subjected to suspension washing for 30 minutes. The collected product was then washed with diethyl ether and dried at 60°C under reduced pressure to obtain Precursor B1 as a brown powder. Precursor B1 is a compound represented by the following formula (1-d):

[0183] [ka]

[0184] <Synthesis of precursor B2> Concentrated sulfuric acid (48 parts by weight) was placed in a four-neck flask equipped with a thermometer and a mechanical stirrer, and potassium nitrate (6.0 parts by weight) was added to completely dissolve the solution. The four-neck flask was then cooled to 0°C. Precursor B1 (3.0 parts by weight) was added to this solution in six 0.5 part by weight increments, ensuring that the internal temperature of the four-neck flask did not exceed 5°C. After the addition of precursor B1, a light brown precipitate formed shortly thereafter. After stirring for 6 hours while the internal temperature of the four-neck flask was kept between 0°C and 5°C, 1Stirring was stopped when H-NMR measurement (solvent: DMSO-d6) confirmed the disappearance of the substrate. This solution was added in small amounts to pure water cooled to 0-5°C, and the precipitate was collected by suction filtration. The collected product was dried under reduced pressure at 60°C to obtain a crude product. The crude product was dissolved in nitrobenzene and stirred at 180°C for 30 minutes. After allowing this solution to cool to room temperature, the precipitate collected by filtration was dried under reduced pressure at 60°C to obtain precursor B2 as a dull yellow powder. Precursor B2 is a compound represented by the following formula (1-e):

[0185] [ka]

[0186] <Synthesis of precursor B3> Pure water (5.5 parts by weight) was placed in a two-neck flask, and concentrated sulfuric acid (40 parts by weight) was slowly added while cooling with ice. Precursor B2 (2.2 parts by weight) was then added to the solution while cooling with ice. This solution was stirred at 95°C for 2 hours, and then added to pure water (200 parts by weight) while cooling with ice. The precipitate was then collected by suction filtration and dried under reduced pressure at 60°C to obtain Precursor B3 as a red powder. Precursor B3 is a compound represented by the following formula (1-f):

[0187] [ka]

[0188] <Synthesis of precursor B4> Precursor B3 (1.6 parts by weight) and N-bromosuccinimide (1.9 parts by weight) were placed in a two-neck flask and purged with nitrogen. Nitrogen-bubbled N,N-dimethylformamide (30 parts by weight) was added and stirred at room temperature for 20 hours. This reaction solution was poured into methanol (200 parts by weight) and stirred at room temperature for 15 minutes. The precipitate was then collected by suction filtration and dried under reduced pressure at 60°C to obtain Precursor B4 as a reddish-brown powder. Precursor B4 is a compound represented by the following formula (1-g):

[0189] [ka]

[0190] <Synthesis of Precursor B5> A recovery flask equipped with a Dimroth condenser was purged with nitrogen. Toluene (5 parts by weight), water (2.5 parts by weight), precursor B4 (0.30 parts by weight), (4-piperidin-1-yl)phenylboronic acid (0.28 parts by weight), potassium carbonate (0.21 parts by weight), and tetrakistriphenylphosphine palladium (0.06 parts by weight) were added and heated with stirring at 80°C for at least 2 hours. After confirming the completion of the reaction by thin-layer chromatography, the mixture was returned to room temperature, purified water was added, and extraction with ethyl acetate was performed. Sodium sulfate was added to the resulting organic layer, which was then dried. The solvent was then removed under reduced pressure using an evaporator. The resulting residue was purified by column chromatography (developing solvent: hexane / ethyl acetate = 10 / 1 to 5 / 1) to obtain precursor B5. Precursor B5 is a compound represented by the following formula (1-h).

[0191] [ka]

[0192] <Synthesis of precursor B6> Precursor B5 (0.20 parts by weight) was placed in a two-neck flask and purged with nitrogen. Nitrobenzene (4.8 parts by weight) and 4-heptylaniline (0.52 parts by weight) were added thereto and stirred at 200°C for 12 hours. The reaction solution was dried under reduced pressure at 75°C to distill off the nitrobenzene and obtain a residue. Methanol was poured into the residue, and the precipitated powder was collected by suction filtration to obtain Precursor B6. Precursor B6 is a compound represented by the following formula (1-i):

[0193] [ka]

[0194] <Synthesis of precursor B7> Precursor B7 was obtained in the same manner as in the synthesis of Precursor B5, except that (4-piperidin-1-yl)phenylboronic acid was replaced with 4-heptyloxyphenylboronic acid. Precursor B7 is a compound represented by the following formula (1-j).

[0195] [ka]

[0196] <Synthesis of precursor B8> Precursor B8 was obtained in the same manner as in the synthesis of precursor B6, except that precursor B5 was replaced with precursor B7. Precursor B8 is a compound represented by the following formula (1-k).

[0197] [ka]

[0198] <Synthesis of dyes in Test Examples 1-14> Precursor B6 (0.20 parts by weight) was placed in a two-neck flask and purged with nitrogen. 2-Propanol (3.1 parts by weight) was added, and the mixture was heated to 80°C. Sodium borohydride (0.22 parts by weight) was then added, and the mixture was stirred for 27 hours. The reaction solution was poured into cold water, and the precipitated powder was collected by suction filtration. It was then purified by column chromatography to obtain the anthraquinone derivative of Test Example 1-14. The anthraquinone derivative of Test Example 1-14 is a compound represented by the following formula (P1-14).

[0199] [ka]

[0200] <Synthesis of dyes in Test Examples 1-15> The anthraquinone derivative of Test Example 1-15 was obtained by the same synthesis as in the dye synthesis process of Test Example 1-14, except that precursor B6 was replaced with precursor B8. The anthraquinone derivative of Test Example 1-15 is a compound represented by the following formula (P1-15).

[0201] [ka]

[0202] (Evaluation method) <Preparation of test specimens for evaluation> Using the anthraquinone derivative of each test example, a dye-containing composition was prepared by mixing the following materials. Mixture of pentaerythritol tetraacrylate and isobornyl acrylate (70% by mass of pentaerythritol tetraacrylate, 30% by mass of isobornyl acrylate): 45 parts by weight Photopolymerization initiator (Omnirad TPO, manufactured by IGM Resins BV): 4.5 parts by weight Anthraquinone derivative: 1 part by weight Methyl ethyl ketone: 50 parts by weight

[0203] A 60 μm-thick polyethylene terephthalate film was used as the transparent substrate, and the dye-containing composition was applied to the surface of the transparent substrate, and the coating film was dried in an oven at 80° C. for 60 seconds. Thereafter, an ultraviolet irradiation device (manufactured by Fusion UV Systems Japan, light source H bulb) was used to irradiate the film with an irradiation dose of 150 mJ / cm. 2 The coating film was cured by irradiating it with ultraviolet light at 1000 kJ / min at 1000 kJ / min. The thickness was adjusted so that the film thickness after curing was 8.0 μm, and a test piece for evaluation was prepared.

[0204] <Evaluation of absorption wavelength and coloring strength> The ultraviolet-visible absorption spectrum of the evaluation test piece for each test example was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.), and the maximum absorption wavelength λmax and the absorbance at that wavelength were determined.

[0205] In evaluating the coloring strength, Test Example 1-10 corresponding to a conventional anthraquinone derivative was used as the standard. If the absorbance was greater than that of Test Example 1-10, it was evaluated as good (○), and if the absorbance was less than that of Test Example 1-10, it was evaluated as poor (×).

[0206] <Evaluation of light resistance> A light resistance test was carried out on the evaluation test specimens of each test example using a xenon weather meter tester (X75, manufactured by Suga Test Instruments Co., Ltd.). In the light resistance test, a UV-blocking adhesive film that absorbs light of 395 nm or less was attached to the front of the evaluation test specimen, and a xenon lamp illuminance of 60 W / cm was used. 2 The test specimens were placed under the conditions of (300nm to 400nm), temperature 45°C, and humidity 50%RH for 120 hours.

[0207] The absorbance of each evaluation test piece before and after the lightfastness test was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.) to determine the absorbance at the wavelength showing the maximum absorbance in the visible light range. The absorbance change rate ΔAbs between before and after the lightfastness test was then calculated. That is, when the measured value before the lightfastness test is absorbance Abs1 and the measured value after the lightfastness test is absorbance Abs2, ΔAbs (%) = {(Abs1 - Abs2) / Abs1} × 100.

[0208] In evaluating light resistance, a ΔAbs of 2% or less was rated as particularly good (◎), a ΔAbs of more than 2% but less than 10% was rated as good (○), and a ΔAbs of more than 10% was rated as poor (×).

[0209] <Dichroic ratio measurement> For each test example, a liquid crystal composition was prepared by mixing an anthraquinone derivative with a cyanocyclohexylbenzene liquid crystal (ZLI-1840, Merck) at a ratio of 1.0% by mass. The liquid crystal composition was then injected into a cell to fabricate a guest-host liquid crystal device. The cell consisted of two glass plates with homogeneously aligned transparent electrodes, facing each other with the alignment surfaces antiparallel. The alignment process was performed by applying a polyimide resin to the transparent electrodes, curing the resin, and then rubbing the resin. The cell thickness was 10 μm.

[0210] The liquid crystal element was placed in the optical path of a spectrophotometer, and the absorbance A / / was measured when linearly polarized light parallel to the rubbing direction was applied to the liquid crystal element, and the absorbance A⊥ was measured when linearly polarized light perpendicular to the rubbing direction was applied to the liquid crystal element.The dichroic ratio, the ratio of absorbance A / / to absorbance A⊥ (A / / / A⊥), was calculated.

[0211] (Evaluation results) Table 1 shows the structure of the anthraquinone derivative, the maximum absorption wavelength λmax, the absorbance at the maximum absorption wavelength λmax, the evaluation results of coloring strength, the rate of change in absorbance ΔAbs, the evaluation results of light fastness, and the dichroic ratio for Test Examples 1-1 to 1-15. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (I), and R, A, and Y in Table 1 are 1 ,Y 2 , Z are R, A, Y in the following formula (I) 1 ,Y 2 , which corresponds to Z.

[0212] [ka]

[0213] [Table 1]

[0214] As shown in Table 1, the anthraquinone derivatives of each test example have a maximum absorption wavelength in the wavelength range of 600 nm or more. Therefore, the anthraquinone derivatives of each test example exhibit a blue color and can be used as cyan dyes.

[0215] Test Examples 1-1 to 1-11, 1-14, and 1-15, in which a substituted phenyl group is directly bonded to the β-position, exhibit significantly higher light resistance than Test Examples 1-12 and 1-13, in which an ether bond is bonded to the β-position.

[0216] Furthermore, in Test Examples 1-1 to 1-9 and 1-14, in which the substituent at the para-position of the directly bonded phenyl group at at least one β-position is an electron-donating group, the absorbance is higher and better coloring strength is obtained than in Test Examples 1-10, 1-11 and 1-15, in which the substituent is not an electron-donating group. Furthermore, Test Examples 1-1 to 1-9 and 1-14 also have higher absorbance than Test Examples 1-12 and 1-13, in which the β-position is an ether bond.

[0217] Furthermore, a comparison of Test Examples 1-3 and 1-9 shows that when both phenyl groups at the β-position have electron-donating groups as substituents, higher absorbance is obtained than when only one of the substituents is an electron-donating group. Furthermore, Test Examples 1-1 to 1-8 confirm that when the electron-donating group is an alkylamino group, piperidyl group, or amino group, the absorbance is more effectively improved than when the electron-donating group is an acetamide group or a hydroxyl group. Furthermore, good dichroic ratios were obtained in all test examples, and it was confirmed that in particular, when two hydroxyl groups are present at the α-position, a high dichroic ratio of 10.0 or more can be obtained.

[0218] [Second Example: Test Example Corresponding to the Second Embodiment] In the second example, synthesis was carried out using precursors A1, A2, and A3 similar to those in the first example.

[0219] (Test Example 2-1) <Synthesis of precursor C1> Precursor A1 (1.0 parts by weight) and p-aminobenzonitrile (2.42 parts by weight) were placed in a two-necked recovery flask and purged with nitrogen. Nitrobenzene (24 parts by weight) was added and heated and stirred in a 190°C oil bath for 5 hours. After cooling the reaction solution to room temperature, the solvent was removed by drying under reduced pressure at 70°C. Methanol was poured into the resulting residue, and the precipitated powder was collected by suction filtration to obtain precursor C1 as a purple powder. Precursor C1 is a compound represented by the following formula (2-a):

[0220] [ka]

[0221] <Synthesis of precursor C2> A two-necked recovery flask was charged with precursor C1 (1.0 parts by weight), (4-pentyloxy)phenylboronic acid (1.18 parts by weight), cesium carbonate (1.74 parts by weight), [1,1-bis(diphenylphosphinoferrocene)]dichloropalladium(II) (0.131 parts by weight), and 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (0.147 parts by weight), and the atmosphere was purged with nitrogen. Toluene (71 parts by weight), ethanol (7.2 parts by weight), and purified water (4.5 parts by weight) were added and stirred in an 80°C oil bath for 2 hours. The reaction solution was cooled to room temperature and separated into dichloromethane and purified water. The organic layer was dried over sodium sulfate. The sodium sulfate was then filtered off, and the remaining solution was concentrated and purified by silica gel column chromatography (eluent: dichloromethane / hexane = 1 / 1) to obtain a crude product. This crude product was purified by column chromatography to obtain precursor C2 as a purple powder. The yield of precursor C2 was 11%. Precursor C2 is a compound represented by the following formula (2-b).

[0222] [ka]

[0223] <Synthesis of dye in Test Example 2-1> Precursor C2 (1 part by weight), iron powder (0.325 parts by weight), and ammonium chloride (0.311 parts by weight) were placed in a two-necked recovery flask and purged with nitrogen. Toluene (27.9 parts by weight), ethanol (8.38 parts by weight), and purified water (5.31 parts by weight) were added and heated and stirred in a 70°C oil bath for 1 hour. The reaction solution was cooled to room temperature, and the insoluble components were filtered through Celite. The solution was then separated into dichloromethane and purified water, washed with purified water and saturated brine, and the organic layer was dried over sodium sulfate. The sodium sulfate was filtered off, and the remaining solution was concentrated and purified by silica gel column chromatography (developing solvent: dichloromethane / hexane = 2 / 1 to 1 / 1) to obtain the anthraquinone derivative of Test Example 2-1 as a purple powder. The anthraquinone derivative of Test Example 2-1 is a compound represented by the following formula (P2-1):

[0224] [ka]

[0225] (Test Example 2-2) <Synthesis of precursor C3> Precursor C3 was obtained in the same manner as in the synthesis of precursor C1, except that p-aminobenzonitrile (2.42 parts by weight) was replaced with p-aminobenzotrifluoride (3.3 parts by weight). Precursor C3 is a compound represented by the following formula (2-c).

[0226] [ka]

[0227] <Synthesis of precursor C4> Precursor C4 was obtained in the same manner as in the synthesis of precursor C2, except that precursor C1 was replaced with precursor C3. Precursor C4 is a compound represented by the following formula (2-d).

[0228] [ka]

[0229] <Synthesis of dye in Test Example 2-2> The anthraquinone derivative of Test Example 2-2 was obtained by the same synthesis as in the dye synthesis process of Test Example 2-1, except that precursor C2 was replaced with precursor C4. The anthraquinone derivative of Test Example 2-2 is a compound represented by the following formula (P2-2).

[0230] [ka]

[0231] (Test Example 2-3) <Synthesis of dye in Test Example 2-3> Precursor C5 was obtained by the same synthesis procedure as in the synthesis of precursor C2, except that (4-pentyloxy)phenylboronic acid was replaced with 4-(trans-4-pentylcyclohexyl)phenylboronic acid. The anthraquinone derivative of Test Example 2-3 was obtained by the same synthesis procedure as in the synthesis of the dye of Test Example 2-1, except that precursor C2 was replaced with precursor C5. The anthraquinone derivative of Test Example 2-3 is a compound represented by the following formula (P2-3).

[0232] [ka]

[0233] (Test Example 2-4) <Synthesis of dyes in Test Example 2-4> In the synthesis process of precursor C2, precursor C1 was changed to precursor C3, and (4-pentyloxy)phenylboronic acid was changed to 4-(trans-4-pentylcyclohexyl)phenylboronic acid, but the synthesis was performed in the same manner to obtain precursor C6. Then, in the synthesis process of the dye of Test Example 2-1, synthesis was performed in the same manner, except that precursor C2 was changed to precursor C6, to obtain the anthraquinone derivative of Test Example 2-4. The anthraquinone derivative of Test Example 2-4 is a compound represented by the following formula (P2-4).

[0234] [ka]

[0235] (Test Example 2-5) <Synthesis of dye of Test Example 2-5> Precursor C7 was obtained by the same synthesis procedure as in the synthesis of precursor C2, except that (4-pentyloxy)phenylboronic acid was replaced with 4-(dimethylamino)phenylboronic acid. The anthraquinone derivative of Test Example 2-5 was obtained by the same synthesis procedure as in the synthesis of the dye of Test Example 2-1, except that precursor C2 was replaced with precursor C7. The anthraquinone derivative of Test Example 2-5 is a compound represented by the following formula (P2-5).

[0236] [ka]

[0237] (Test Example 2-6) The dye of Test Example 1-10 in the first embodiment was the anthraquinone derivative of Test Example 2-6, which is a compound represented by the following formula (P2-6).

[0238] [ka]

[0239] (Test Example 2-7) The dye of Test Example 1-11 in the first embodiment was the anthraquinone derivative of Test Example 2-7. The anthraquinone derivative of Test Example 2-7 is a compound represented by the following formula (P2-7).

[0240] [ka]

[0241] (Test Example 2-8) <Synthesis of dye of Test Example 2-8> The anthraquinone derivative of Test Example 2-8 was obtained by the same synthesis as in Test Example 1-1 of Example 1, except that 4-dimethylaminophenylboronic acid was replaced with 4-(trans-4-pentylcyclohexyl)phenylboronic acid. The anthraquinone derivative of Test Example 2-8 is a compound represented by the following formula (P2-8).

[0242] [ka]

[0243] (Test Example 2-9) <Synthesis of dye of Test Example 2-9> The anthraquinone derivative of Test Example 2-9 was obtained by the same synthesis as in Test Example 1-1 of the first embodiment, except that precursor A2 was changed to precursor A3 and 4-dimethylaminophenylboronic acid was changed to 4-(trans-4-pentylcyclohexyl)phenylboronic acid. The anthraquinone derivative of Test Example 2-9 is a compound represented by the following formula (P2-9).

[0244] [ka]

[0245] (Test Example 2-10) The dye of Test Example 1-12 in the first embodiment was the anthraquinone derivative of Test Example 2-10. The anthraquinone derivative of Test Example 2-10 is a compound represented by the following formula (P2-10).

[0246] [ka]

[0247] (Test Example 2-11) <Synthesis of precursor C8> Precursor C8 was obtained by the same synthesis as in Test Example 1-12 of Example 1, except that precursor A3 was replaced with precursor C1. Precursor C8 is a compound represented by the following formula (2-e).

[0248] [ka]

[0249] <Synthesis of dye of Test Example 2-11> The anthraquinone derivative of Test Example 2-11 was obtained by the same synthesis as in the dye synthesis process of Test Example 2-1, except that precursor C2 was replaced with precursor C8. The anthraquinone derivative of Test Example 2-11 is a compound represented by the following formula (P2-11).

[0250] [ka]

[0251] (Evaluation method) For the anthraquinone derivatives of Test Examples 2-1 to 2-11, evaluation specimens were prepared in the same manner as in Example 1, and the absorption wavelength, coloring strength, lightfastness, and dichroic ratio were evaluated. In the evaluation of coloring strength, Test Example 2-6, which corresponds to a conventional anthraquinone derivative, was used as the standard, and cases where the absorbance was greater than that of Test Example 2-6 were evaluated as good (◯), and cases where the absorbance was equal to or less than that of Test Example 2-6 were evaluated as poor (×).

[0252] (Evaluation results) Table 2 shows the structure of the anthraquinone derivative, the maximum absorption wavelength λmax, the absorbance at the maximum absorption wavelength λmax, the evaluation results of coloring strength, the rate of change in absorbance ΔAbs, the evaluation results of light fastness, and the dichroic ratio for Test Examples 2-1 to 2-11. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (I), and R, A, and Y in Table 2 are 1 ,Y 2 , Z are R, A, Y in the following formula (I) 1 ,Y 2 , which corresponds to Z.

[0253] [ka]

[0254] [Table 2]

[0255] As shown in Table 2, the anthraquinone derivatives of each test example have a maximum absorption wavelength in the wavelength range of 600 nm or more. Therefore, the anthraquinone derivatives of each test example exhibit a blue color and can be used as cyan dyes.

[0256] Furthermore, Test Examples 2-1 to 2-9, in which a substituted phenyl group is directly bonded to the β-position, exhibited extremely high light resistance compared to Test Examples 2-10 and 2-11, in which an ether bond is bonded to the β-position.

[0257] Furthermore, in Test Examples 2-1 to 2-5, in which a substituted phenyl group is directly bonded to the β-position and the substituent at the para-position of the anilino group at the α-position is an electron-withdrawing group, the absorbance is higher and better coloring strength is obtained than in Test Examples 2-6 to 2-9, in which the substituent is not an electron-withdrawing group. Furthermore, Test Examples 2-1 to 2-5 also have higher absorbance than Test Examples 2-10 and 2-11, in which the β-position is an ether bond.

[0258] Furthermore, with reference to Test Examples 2-1 to 2-5, it was confirmed that Test Example 2-5, in which the phenyl group at the β-position has an electron-donating group as a para-substituent in addition to the electron-withdrawing group at the α-position, exhibits a particularly high absorbance compared to other Test Examples that do not have such an electron-donating group. It was also confirmed that a good dichroic ratio was obtained in each test example.

[0259] [Third Example: Test Example Corresponding to the Third Embodiment] In the third example, synthesis was carried out using precursors A1 to A3 and B1 to B4 similar to those in the first example.

[0260] (Test Example 3-1) The dye of Test Example 2-8 in the second embodiment was the anthraquinone derivative of Test Example 3-1, which is a compound represented by the following formula (P3-1).

[0261] [ka]

[0262] (Test Example 3-2) <Synthesis of dye in Test Example 3-2> The anthraquinone derivative of Test Example 3-2 was obtained by the same synthesis as in Test Example 1-1 of Example 1, except that 4-dimethylaminophenylboronic acid was replaced with 4-ethylcyclohexylphenylboronic acid. The anthraquinone derivative of Test Example 3-2 is a compound represented by the following formula (P3-2).

[0263] [ka]

[0264] (Test Example 3-3) <Synthesis of dye in Test Example 3-3> The anthraquinone derivative of Test Example 3-3 was obtained by the same synthesis as in Test Example 1-1 of Example 1, except that 4-dimethylaminophenylboronic acid was replaced with 4-methylcyclohexylphenylboronic acid. The anthraquinone derivative of Test Example 3-3 is a compound represented by the following formula (P3-3).

[0265] [ka]

[0266] (Test Example 3-4) <Synthesis of dyes in Test Example 3-4> The anthraquinone derivative of Test Example 3-4 was obtained by the same synthesis as in Test Example 1-1 of Example 1, except that 4-dimethylaminophenylboronic acid was replaced with cyclohexylphenylboronic acid. The anthraquinone derivative of Test Example 3-4 is a compound represented by the following formula (P3-4).

[0267] [ka]

[0268] (Test Example 3-5) The dye of Test Example 2-9 in the second embodiment was the anthraquinone derivative of Test Example 3-5, which is a compound represented by the following formula (P3-5).

[0269] [ka]

[0270] (Test Example 3-6) <Synthesis of dyes in Test Examples 3-6> In the synthesis process of the dye of Test Example 1-1 of the first embodiment, 1.2 equivalents of 4-heptyloxyphenylboronic acid were added instead of 4-dimethylaminophenylboronic acid, and the reaction solution was stirred at 80°C for 1 hour. Then, 1.2 equivalents of 4-pentylcyclohexylphenylboronic acid was added, and the mixture was heated and stirred at 80°C for 2 hours or more. Extraction and purification were then carried out in the same manner as in the synthesis process of the dye of Test Example 1-1, yielding the anthraquinone derivative of Test Example 3-6. The anthraquinone derivative of Test Example 3-6 is a compound represented by the following formula (P3-6).

[0271] [ka]

[0272] (Test Example 3-7) <Synthesis of dyes in Test Examples 3-7> In the synthesis process of the dye of Test Example 1-1 of the first embodiment, 1.2 equivalents of 4-monobutylaminophenylboronic acid were added instead of 4-dimethylaminophenylboronic acid, and the reaction solution was stirred at 80°C for 1 hour. Then, 1.2 equivalents of 4-pentylcyclohexylphenylboronic acid was added, and the mixture was heated and stirred at 80°C for 2 hours or more. Extraction and purification were then carried out in the same manner as in the synthesis process of the dye of Test Example 1-1, yielding the anthraquinone derivative of Test Example 3-7. The anthraquinone derivative of Test Example 3-7 is a compound represented by the following formula (P3-7):

[0273] [ka]

[0274] (Test Example 3-8) The dye of Test Example 1-10 in the first embodiment was the anthraquinone derivative of Test Example 3-8. The anthraquinone derivative of Test Example 3-8 is a compound represented by the following formula (P3-8).

[0275] [ka]

[0276] (Test Example 3-9) The dye of Test Example 1-11 in the first embodiment was the anthraquinone derivative of Test Example 3-9. The anthraquinone derivative of Test Example 3-9 is a compound represented by the following formula (P3-9).

[0277] [ka]

[0278] (Test Example 3-10) The dye of Test Example 1-3 in the first embodiment was replaced with the anthraquinone derivative of Test Example 3-10. The anthraquinone derivative of Test Example 3-10 is a compound represented by the following formula (P3-10).

[0279] [ka]

[0280] (Test Example 3-11) <Synthesis of dye of Test Example 3-11> The anthraquinone derivative of Test Example 3-11 was obtained by the same synthesis procedure as in Test Example 1-12 of the first embodiment, except that 4-heptyloxyphenol was replaced with 4-heptylcyclohexylphenol and precursor A3 was replaced with precursor A2. The anthraquinone derivative of Test Example 3-11 is a compound represented by the following formula (P3-11).

[0281] [ka]

[0282] (Test Example 3-12) <Synthesis of precursor B9> Precursor B9 was obtained in the same manner as in Example 1, except that (4-piperidin-1-yl)phenylboronic acid was replaced with (4-pentylcyclohexyl)phenylboronic acid in the synthesis of precursor B5. Precursor B9 is a compound represented by the following formula (3-a).

[0283] [ka]

[0284] <Synthesis of precursor B10> Precursor B10 was obtained by the same synthesis as in Example 1, except that precursor B5 was replaced with precursor B9. Precursor B10 is a compound represented by the following formula (3-b).

[0285] [ka]

[0286] <Synthesis of dye of Test Example 3-12> The anthraquinone derivative of Test Example 3-12 was obtained by the same synthesis as in the dye synthesis process of Test Example 1-14 in Example 1, except that precursor B6 was replaced with precursor B10. The anthraquinone derivative of Test Example 3-12 is a compound represented by the following formula (P3-12).

[0287] [ka]

[0288] (Test Example 3-13) The dye of Test Example 1-15 in the first embodiment was the anthraquinone derivative of Test Example 3-13. The anthraquinone derivative of Test Example 3-13 is a compound represented by the following formula (P3-13).

[0289] [ka]

[0290] (Evaluation method) For the anthraquinone derivatives of Test Examples 3-1 to 3-13, evaluation specimens were prepared in the same manner as in Example 1, and the absorption wavelength, light resistance, and dichroic ratio were evaluated.

[0291] In addition, the degree of minor absorption was determined by normalizing the absorbance at the maximum absorption wavelength in the UV-visible absorption spectrum to 1.0, and then using the resulting spectrum, the sum of absorbance in the short wavelength region from 380 nm to 480 nm was calculated. The sum of absorbance was the integral value corresponding to the area in the range from 380 nm to 480 nm in the normalized spectrum. Note that absorption in the short wavelength region from 380 nm to 480 nm is defined as minor absorption.

[0292] (Evaluation results) Table 3 shows the structure of the anthraquinone derivative, the maximum absorption wavelength λmax, the degree of secondary absorption, the rate of change in absorbance ΔAbs, the evaluation results of light resistance, and the dichroic ratio for Test Examples 3-1 to 3-13. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (I), and R, A, Y in Table 3 are 1 ,Y 2 , Z are R, A, Y in the following formula (I) 1 ,Y 2 , which corresponds to Z.

[0293] [ka]

[0294] [Table 3]

[0295] As shown in Table 3, the anthraquinone derivatives of each test example have an absorption maximum wavelength in the wavelength range of 600 nm or more. Therefore, the anthraquinone derivatives of each test example exhibit a blue color and can be used as cyan dyes.

[0296] Furthermore, Test Examples 3-1 to 3-10, 3-12, and 3-13, in which a substituted phenyl group is directly bonded to the β-position, exhibit significantly higher light resistance than Test Example 3-11, in which an ether bond is bonded to the β-position.

[0297] Furthermore, comparing Test Examples 3-1 to 3-4 with Test Examples 3-8 and 3-10, it was confirmed that the degree of side absorption can be reduced by using a substituted or unsubstituted cyclohexyl group as the para-substituent of the phenyl group at the β-position. Similarly, comparing Test Example 3-5 with Test Example 3-9, and comparing Test Example 3-12 with Test Example 3-13, it was also confirmed that the degree of side absorption can be reduced by using a cyclohexyl group as the para-substituent of the β-position. This indicates that an anthraquinone derivative can exhibit excellent blueness with reduced yellowness if the para-substituent of the β-position is a cyclohexyl group.

[0298] Furthermore, comparisons between Test Examples 3-6 and 3-8, and between Test Examples 3-7 and 3-10, confirmed that the effect of suppressing the degree of side absorption can be obtained even when there is only one cyclohexyl group at the β-para position. Furthermore, comparisons between Test Examples 3-1 and 3-6 and 3-7 confirmed that when both substituents at the β-para positions are cyclohexyl groups, the effect of suppressing the degree of side absorption is greater than when only one is a cyclohexyl group. Furthermore, good dichroic ratios were obtained in all test examples, and it was confirmed that a particularly high dichroic ratio was obtained when two hydroxyl groups were present at the α-position.

[0299] [Fourth Example: Test Example Corresponding to the Fourth Embodiment] In the fourth example, synthesis was carried out using the same precursor as in the first to third examples.

[0300] (Test Example 4-1) <Synthesis of precursor B11> A two-neck flask was charged with 4-heptyloxyphenol (0.45 parts by weight) and potassium carbonate (0.30 parts by weight), and the atmosphere was purged with nitrogen. Dehydrated N-methyl-2-pyrrolidone (20 parts by weight) was added, and the mixture was stirred at 120°C for 3 hours. Precursor B4 (0.50 parts by weight) was added to this solution, and the mixture was stirred at 80°C for 7 hours. The reaction solution was returned to room temperature, and water / dichloromethane was added to separate the solution. The organic layer obtained by the separation was dried over sodium sulfate and then concentrated using an evaporator. The mixture was purified by silica gel column chromatography (developing solvent: hexane / dichloromethane = 1 / 4, with 1% by weight of triethylamine added), and the recovered product was dried under reduced pressure at 60°C to obtain Precursor B11 as a red powder. Precursor B11 is a compound represented by the following formula (4-a):

[0301] [ka]

[0302] <Synthesis of precursor B12> Precursor B11 (0.20 parts by weight) was placed in a two-neck flask and purged with nitrogen. Nitrobenzene (4.8 parts by weight) and 4-heptylaniline (0.52 parts by weight) were added and stirred at 200°C for 12 hours. The reaction solution was dried under reduced pressure at 75°C to remove nitrobenzene and obtain a residue. Methanol was poured into the residue, and the precipitated powder was collected by suction filtration to obtain precursor B12 as a purple powder. Precursor B12 is a compound represented by the following formula (4-b):

[0303] [ka]

[0304] <Synthesis of dye of Test Example 4-1> The anthraquinone derivative of Test Example 4-1 was obtained by the same synthesis as in Test Example 1-14 of the first embodiment, except that precursor B6 was replaced with precursor B12. The anthraquinone derivative of Test Example 4-1 is a compound represented by the following formula (P4-1).

[0305] [ka]

[0306] (Test Example 4-2) The dye of Test Example 1-10 in Example 1 was the anthraquinone derivative of Test Example 4-2, which is a compound represented by the following formula (P4-2).

[0307] [ka]

[0308] (Test Example 4-3) The dye of Test Example 2-8 in the second embodiment was the anthraquinone derivative of Test Example 4-3, which is a compound represented by the following formula (P4-3).

[0309] [ka]

[0310] (Test Example 4-4) The dye of Test Example 1-11 in Example 1 was the anthraquinone derivative of Test Example 4-4, which is a compound represented by the following formula (P4-4).

[0311] [ka]

[0312] (Test Example 4-5) <Synthesis of dyes in Test Examples 4-5> In the synthesis process of the dye of Test Example 1-1 of the first embodiment, 1.2 equivalents of 4-heptyloxyphenylboronic acid were added instead of 4-dimethylaminophenylboronic acid, and the reaction solution was stirred at 80°C for 1 hour. Then, 1.2 equivalents of 4-pentyloxybiphenylboronic acid was added, and the mixture was heated and stirred at 80°C for 2 hours or more. Extraction and purification were then carried out in the same manner as in the synthesis process of the dye of Test Example 1-1, yielding the anthraquinone derivative of Test Example 4-5. The anthraquinone derivative of Test Example 4-5 is a compound represented by the following formula (P4-5):

[0313] [ka]

[0314] (Test Example 4-6) The dye of Test Example 3-6 in the third embodiment was the anthraquinone derivative of Test Example 4-6, which is a compound represented by the following formula (P4-6).

[0315] [ka]

[0316] (Test Example 4-7) The dye of Test Example 2-9 in the second embodiment was the anthraquinone derivative of Test Example 4-7. The anthraquinone derivative of Test Example 4-7 is a compound represented by the following formula (P4-7).

[0317] [ka]

[0318] (Test Example 4-8) The dye of Test Example 2-3 in the second embodiment was replaced with the anthraquinone derivative of Test Example 4-8. The anthraquinone derivative of Test Example 4-8 is a compound represented by the following formula (P4-8).

[0319] [ka]

[0320] (Test Example 4-9) The dye of Test Example 3-7 in the third embodiment was replaced with the anthraquinone derivative of Test Example 4-9. The anthraquinone derivative of Test Example 4-9 is a compound represented by the following formula (P4-9).

[0321] [ka]

[0322] (Test Examples 4-10 to 4-12) <Synthesis of precursor D1> Toluene (100 parts by weight), ethanol (20 parts by weight), water (10 parts by weight), precursor A1 (1 part by weight), 4-pentylcyclohexylphenylboronic acid (1.2 parts by weight), triethylamine (0.62 parts by weight), and tris(dibenzylideneacetone)dipalladium (0.2 parts by weight) were added to a two-necked recovery flask and stirred at 80°C for at least 2 hours. After confirming the completion of the reaction by thin-layer chromatography, the reaction solution was returned to room temperature, purified water was added, and extraction with ethyl acetate was performed. Sodium sulfate was added to the resulting organic layer, which was then dried. The solvent was then removed under reduced pressure using an evaporator. The resulting solid was purified by column chromatography (developing solvent: hexane / dichloromethane = 1 / 1 to 2 / 3) to obtain precursor D1 as a dark red solid. Precursor D1 is a compound represented by the following formula (4-c).

[0323] [ka]

[0324] <Synthesis of precursor D2> Precursor D2 was obtained in the same manner as in the synthesis of precursor D1, except that 4-pentylcyclohexylphenylboronic acid was replaced with 4-heptyloxyphenylboronic acid. Precursor D2 is a compound represented by the following formula (4-d).

[0325] [ka]

[0326] <Synthesis of precursor D3> Precursor D3 was obtained in the same manner as in the synthesis of precursor D1, except that 4-pentylcyclohexylphenylboronic acid was replaced with 4-monobutylaminophenylboronic acid. Precursor D3 is a compound represented by the following formula (4-e).

[0327] [ka]

[0328] <Synthesis of dyes in Test Examples 4-10> Precursor D1 (1.0 parts by weight) was placed in a two-necked recovery flask and the system was purged with nitrogen. Tetrahydrofuran (18.0 parts by weight) was then added. Next, in a separate flask, 4-methoxybenzenethiol (3.3 parts by weight) and pyridine (1.6 parts by weight) were mixed and stirred at room temperature for 30 minutes to prepare a solution. This solution was added to the solution containing Precursor D1 in the recovery flask and heated and stirred at 50°C. After confirming the completion of the reaction by thin-layer chromatography, the reaction solution was allowed to cool to room temperature. Dilute hydrochloric acid (a mixture of 35% hydrochloric acid (20.0 parts by weight) and purified water (80.0 parts by weight)) was added, and the precipitated solid was collected by filtration. The collected solid (1.0 parts by weight) and zinc powder (0.5 parts by weight) were placed in a two-necked recovery flask and the system was purged with nitrogen. Dichloromethane (200.0 parts by weight) and acetic acid (18.0 parts by weight) were then added and stirred at room temperature. After confirming the completion of the reaction by thin layer chromatography, the reaction solution was filtered, pure water was added to the filtrate, and the mixture was extracted with dichloromethane. Sodium sulfate was added to the obtained organic layer, and the mixture was dried. The solvent was then removed under reduced pressure using an evaporator. The resulting residue was purified by column chromatography (developing solvent: hexane / dichloromethane = 1 / 1 to 1 / 3) to obtain the anthraquinone derivative of Test Example 4-10 as a dark blue solid. The anthraquinone derivative of Test Example 4-10 is a compound represented by the following formula (P4-10).

[0329] [ka]

[0330] <Synthesis of dye of Test Example 4-11> The anthraquinone derivative of Test Example 4-11 was obtained by the same synthesis as in the dye synthesis process of Test Example 4-10, except that precursor D1 was replaced with precursor D2. The anthraquinone derivative of Test Example 4-11 is a compound represented by the following formula (P4-11).

[0331] [ka]

[0332] <Synthesis of dye of Test Example 4-12> The anthraquinone derivative of Test Example 4-12 was obtained by the same synthesis as in the dye synthesis process of Test Example 4-10, except that precursor D1 was replaced with precursor D3. The anthraquinone derivative of Test Example 4-12 is a compound represented by the following formula (P4-12).

[0333] [ka]

[0334] (Test Example 4-13) <Synthesis of dye of Test Example 4-13> A two-neck flask was charged with 4-heptyloxyphenol (0.36 parts by weight) and potassium carbonate (0.24 parts by weight), and the flask was purged with nitrogen. Dehydrated N-methyl-2-pyrrolidone (10 parts by weight) was added and stirred at 120°C for 3 hours. Precursor A2 (0.50 parts by weight) was then added and stirred at 120°C for 7 hours. The reaction solution was returned to room temperature, and water / dichloromethane was added and the mixture was separated. The resulting organic layer was dried over sodium sulfate and concentrated using an evaporator. The mixture was then purified by silica gel column chromatography and dried under reduced pressure at 60°C to obtain the anthraquinone derivative of Test Example 4-13 as a blue powder. The anthraquinone derivative of Test Example 4-13 is a compound represented by the following formula (P4-13):

[0335] [ka]

[0336] (Test Example 4-14) <Synthesis of dye of Test Example 4-14> The anthraquinone derivative of Test Example 4-14 was obtained in the same manner as in the synthesis of the dye of Test Example 4-13, except that 4-heptylphenol was used instead of 4-heptyloxyphenol. The anthraquinone derivative of Test Example 4-14 is a compound represented by the following formula (P4-14).

[0337] [ka]

[0338] (Test Example 4-15) <Synthesis of dye of Test Example 4-15> The anthraquinone derivative of Test Example 4-15 was obtained by the same synthesis as in Test Example 4-13, except that 4-heptyloxyphenol was replaced with 4-heptylcyclohexylphenol. The anthraquinone derivative of Test Example 4-15 is a compound represented by the following formula (P4-15). Note that the anthraquinone derivative of Test Example 4-15 is the same compound as the anthraquinone derivative of Test Example 3-11.

[0339] [ka]

[0340] (Evaluation method) <Evaluation of absorption wavelength and light resistance> For the anthraquinone derivatives of Test Examples 4-1 to 4-15, evaluation specimens were prepared in the same manner as in Example 1, and the absorption wavelength and light resistance were evaluated.

[0341] <Calculation of total energy difference ΔE> For the anthraquinone derivatives of Test Examples 4-1 to 4-15, the total energy difference ΔE before and after the reaction represented by the above-mentioned reaction formula (4-2) was calculated. The total energy difference ΔE was calculated using the quantum chemistry calculation program GAMESS, with the functional set to B3LYP and the basis set set to 6-31G(d), according to the following procedure.

[0342] (1) For each anthraquinone derivative in the test example, structural optimization was performed using SCF calculations, and the total energy Ep of the molecule in the optimized structure was obtained. (2) Using the structure of the anthraquinone derivative after structural optimization, in which hydrogen was added to the anthraquinone skeleton, as the initial structure of the hydrogen adduct, structural optimization of the hydrogen adduct was performed by SCF calculation. Then, the total energy Ek of the molecule in the optimized structure was obtained for the hydrogen adduct.

[0343] The hydrogen adduct can have four stereoisomers depending on the position of the substituent at the β-position. Of the four stereoisomers, the most stable structure, which is the structure with the most stable energy, is thought to be the most likely to be formed. Therefore, the most stable structure was adopted as the three-dimensional structure of the hydrogen adduct. The most stable structure was searched for by performing a relaxed scan calculation, which rotates the dihedral angle at the bonding site of the β-position substituent. (3) The total energy difference ΔE was calculated using the formula ΔE=Ek-Ep.

[0344] (Evaluation results) Table 4 shows the structure of the anthraquinone derivative, the absorption maximum wavelength λmax, the total energy difference ΔE, the absorbance change rate ΔAbs, and the evaluation results of light resistance for Test Examples 4-1 to 4-15. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (II), and R, A, X, and Y in Table 4 are 1 ,Y 2 , Z are R, A, X, and Y in the following formula (II). 1 ,Y 2 , which corresponds to Z.

[0345] [ka]

[0346] [Table 4]

[0347] As shown in Table 4, the anthraquinone derivatives of each test example have a maximum absorption wavelength in the wavelength range of 580 nm or more, and therefore can be used as cyan dyes. Furthermore, high lightfastness was obtained in Test Examples 4-1 to 4-12, in which the total energy difference ΔE was -16 kcal / mol or more. On the other hand, lightfastness was poor in Test Examples 4-13 to 4-15, in which the total energy difference ΔE was less than -16 kcal / mol. The results in Table 4 suggest that a structure without a hydroxyl group at the α-position or a structure in which a substituent is directly bonded to the β-position increases the total energy difference ΔE and provides high lightfastness.

[0348] Fifth Example: Test Example Corresponding to the Fifth Embodiment In the fifth example, synthesis was carried out using the same precursors as in the first to fourth examples.

[0349] (Test Example 5-1) The dye of Test Example 1-10 in the first embodiment was the anthraquinone derivative of Test Example 5-1, which is a compound represented by the following formula (P5-1).

[0350] [ka]

[0351] (Test Example 5-2) The dye of Test Example 1-11 in the first embodiment was the anthraquinone derivative of Test Example 5-2, which is a compound represented by the following formula (P5-2).

[0352] [ka]

[0353] (Test Example 5-3) <Synthesis of dye of Test Example 5-3> In the synthesis process of the dye of Test Example 1-1 of the first embodiment, precursor A2 was changed to precursor A3, and 1.2 equivalents of 4-heptyloxyphenylboronic acid were added instead of 4-dimethylaminophenylboronic acid. The reaction solution was stirred at 80°C for 1 hour, and then 1.2 equivalents of 4-(trans-4-pentylcyclohexyl)phenylboronic acid was added and heated and stirred at 80°C for 2 hours or more. Extraction and purification were then performed in the same manner as in the synthesis process of the dye of Test Example 1-1, yielding the anthraquinone derivative of Test Example 5-3. The anthraquinone derivative of Test Example 5-3 is a compound represented by the following formula (P5-3).

[0354] [ka]

[0355] (Test Example 5-4) The dye of Test Example 1-2 in Example 1 was replaced with the anthraquinone derivative of Test Example 5-4, which is a compound represented by the following formula (P5-4).

[0356] [ka]

[0357] (Test Example 5-5) <Synthesis of dye of Test Example 5-5> The anthraquinone derivative of Test Example 5-5 was obtained by the same synthesis as in Test Example 4-10 of the fourth embodiment, except that precursor D1 was changed to precursor D2 and 4-methoxybenzenethiol was changed to 4-heptyloxybenzenethiol. The anthraquinone derivative of Test Example 5-5 is a compound represented by the following formula (P5-5).

[0358] [ka]

[0359] (Test Example 5-6) The dye of Test Example 4-11 in the fourth embodiment was the anthraquinone derivative of Test Example 5-6, which is a compound represented by the following formula (P5-6).

[0360] [ka]

[0361] (Test Examples 5-7) <Synthesis of dyes in Test Examples 5-7> The anthraquinone derivative of Test Example 5-7 was obtained by the same synthesis as in Test Example 4-10 of the fourth embodiment, except that 4-methoxybenzenethiol was replaced with 4-heptyloxybenzenethiol. The anthraquinone derivative of Test Example 5-7 is a compound represented by the following formula (P5-7).

[0362] [ka]

[0363] (Test Examples 5-8) <Synthesis of dyes in Test Examples 5-8> The anthraquinone derivative of Test Example 5-8 was obtained by the same synthesis as in Test Example 4-10 of the fourth embodiment, except that precursor D1 was changed to precursor D2 and 4-methoxybenzenethiol was changed to 4-cyanobenzenethiol. The anthraquinone derivative of Test Example 5-8 is a compound represented by the following formula (P5-8).

[0364] [ka]

[0365] (Test Example 5-9) <Synthesis of precursor B13> Precursor B13 was obtained by the same synthesis as in Example 1, except that precursor A1 was replaced with precursor B4. Precursor B13 is a compound represented by the following formula (5-a).

[0366] [ka]

[0367] <Synthesis of dyes in Test Examples 5-9> The anthraquinone derivative of Test Example 5-9 was obtained by performing the same synthesis as in Test Example 1-1 of the first embodiment, except that precursor A2 was changed to precursor B13 and 4-dimethylaminophenylboronic acid was changed to 4-heptyloxyphenylboronic acid. The anthraquinone derivative of Test Example 5-9 is a compound represented by the following formula (P5-9). Note that the anthraquinone derivative of Test Example 5-9 is the same compound as the anthraquinone derivative of Test Example 1-15.

[0368] [ka]

[0369] (Test Examples 5-10) The dye of Test Example 4-1 in the fourth embodiment was replaced with the anthraquinone derivative of Test Example 5-10, which is a compound represented by the following formula (P5-10).

[0370] [ka]

[0371] (Test Example 5-11) The dye of Test Example 4-13 in the fourth embodiment was the anthraquinone derivative of Test Example 5-11. The anthraquinone derivative of Test Example 5-11 is a compound represented by the following formula (P5-11).

[0372] [ka]

[0373] (Test Example 5-12) The dye of Test Example 4-14 in the fourth embodiment was the anthraquinone derivative of Test Example 5-12. The anthraquinone derivative of Test Example 5-12 is a compound represented by the following formula (P5-12).

[0374] [ka]

[0375] (Evaluation method) <Evaluation of absorption wavelength and light resistance> For the anthraquinone derivatives of Test Examples 5-1 to 5-12, evaluation specimens were prepared in the same manner as in Example 1, and the absorption wavelength and light resistance were evaluated.

[0376] <Thermogravimetry> The anthraquinone derivatives of Test Examples 5-1 to 5-12 were subjected to weight measurement using a simultaneous thermogravimetry and differential thermal analyzer (STA7200RV, Hitachi High-Tech Science) under conditions of a gas flow rate of 200 mL / min and a temperature rise rate of 10°C / min, raising the temperature from 30°C to 550°C. Air was used as the gas. The 10% weight loss temperature was determined based on the weight at the start of the temperature rise.

[0377] (Evaluation results) Table 5 shows the structure of the anthraquinone derivative, the absorption maximum wavelength λmax, the 10% weight loss temperature, the absorbance change rate ΔAbs, and the evaluation results of light resistance for Test Examples 5-1 to 5-12. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (II), and R, A, X, and Y in Table 5 are 1 ,Y 2 , Z are R, A, X, and Y in the following formula (II). 1 ,Y 2 , which corresponds to Z.

[0378] [ka]

[0379] [Table 5]

[0380] As shown in Table 5, the anthraquinone derivatives of each test example have a maximum absorption wavelength in the wavelength range of 580 nm or more, and therefore can be used as cyan dyes. High light resistance was obtained in Test Examples 5-1 to 5-10, in which the 10% weight loss temperature was 350° C. or higher. On the other hand, Test Examples 5-11 and 5-12, in which the 10% weight loss temperature was less than 350° C., exhibited poor light resistance.

[0381] The results in Table 5 suggest that structures without a hydroxyl group at the α-position or structures in which a substituent is directly bonded to the β-position have a higher 10% weight loss temperature and higher light resistance. It was also confirmed that structures in which X is -NH- tend to have higher 10% weight loss temperatures and light resistance than structures in which X is a sulfur atom. Furthermore, 1 ,Y 2 It was confirmed that when is an electron donating group such as an alkylamino group, the 10% weight loss temperature and light resistance tend to be lower.

[0382] [Sixth Example: Test Example Corresponding to the Sixth Embodiment] In the sixth example, synthesis was carried out using the same precursor as in the first to fifth examples.

[0383] (Test Example 6-1) The dye of Test Example 1-11 in the first embodiment was the anthraquinone derivative of Test Example 6-1, which is a compound represented by the following formula (P6-1).

[0384] [ka]

[0385] (Test Example 6-2) The dye of Test Example 2-8 in the second embodiment was the anthraquinone derivative of Test Example 6-2, which is a compound represented by the following formula (P6-2).

[0386] [ka]

[0387] (Test Example 6-3) The dye of Test Example 1-3 in Example 1 was replaced with the anthraquinone derivative of Test Example 6-3, which is a compound represented by the following formula (P6-3).

[0388] [ka]

[0389] (Test Example 6-4) The dye of Test Example 1-2 in Example 1 was replaced with the anthraquinone derivative of Test Example 6-4, which is a compound represented by the following formula (P6-4).

[0390] [ka]

[0391] (Test Example 6-5) <Synthesis of dye of Test Example 6-5> In the synthesis of the dye of Test Example 1-1 of the first embodiment, 1.2 equivalents of 4-(trans-4-pentylcyclohexyl)phenylboronic acid were added instead of 4-dimethylaminophenylboronic acid, and the reaction solution was stirred at 80°C for 1 hour. Then, 1.2 equivalents of 4-pentyloxybiphenylboronic acid was added, and the mixture was heated and stirred at 80°C for 2 hours or more. Extraction and purification were then carried out in the same manner as in the synthesis of the dye of Test Example 1-1, yielding the anthraquinone derivative of Test Example 6-5. The anthraquinone derivative of Test Example 6-5 is a compound represented by the following formula (P6-5):

[0392] [ka]

[0393] (Test Example 6-6) <Synthesis of dye in Test Example 6-6> In the synthesis process of the dye of Test Example 1-1 of the first embodiment, 1.2 equivalents of 4-(trans-4-pentylcyclohexyl)phenylboronic acid were added instead of 4-dimethylaminophenylboronic acid, and the reaction solution was stirred at 80°C for 1 hour. Then, 1.2 equivalents of 4-monobutylaminophenylboronic acid was added, and the mixture was heated and stirred at 80°C for 2 hours or more. Extraction and purification were then carried out in the same manner as in the synthesis process of the dye of Test Example 1-1, yielding the anthraquinone derivative of Test Example 6-6. The anthraquinone derivative of Test Example 6-6 is a compound represented by the following formula (P6-6):

[0394] [ka]

[0395] (Test Examples 6-7) The dye of Test Example 5-5 in the fifth embodiment was replaced with the anthraquinone derivative of Test Example 6-7, which is a compound represented by the following formula (P6-7).

[0396] [ka]

[0397] (Test Examples 6-8) The dye of Test Example 4-12 in the fourth embodiment was the anthraquinone derivative of Test Example 6-8. The anthraquinone derivative of Test Example 6-8 is a compound represented by the following formula (P6-8).

[0398] [ka]

[0399] (Test Example 6-9) The dye of Test Example 5-7 in the fifth embodiment was replaced with the anthraquinone derivative of Test Example 6 to 9. The anthraquinone derivative of Test Example 6 to 9 is a compound represented by the following formula (P6-9).

[0400] [ka]

[0401] (Test Example 6-10) <Synthesis of precursor B14> Precursor B14 was obtained by the same synthesis procedure as in Example 1 for precursor A2, except that precursor A1 was replaced with precursor B4 and 4-heptyloxyaniline was used instead of 4-heptylaniline. Precursor B14 is a compound represented by the following formula (6-a):

[0402] [ka]

[0403] <Synthesis of dyes in Test Examples 6-10> The anthraquinone derivative of Test Example 6-10 was obtained by the same synthesis as in Test Example 1-1 of the first embodiment, except that precursor A2 was changed to precursor B14 and 4-dimethylaminophenylboronic acid was changed to 4-heptyloxyphenylboronic acid. The anthraquinone derivative of Test Example 6-10 is a compound represented by the following formula (P6-10).

[0404] [ka]

[0405] (Test Example 6-11) <Synthesis of dyes in Test Examples 6-11> The anthraquinone derivative of Test Example 6-11 was obtained by the same synthesis as in Test Example 4-13 of the fourth embodiment, except that 4-heptyloxyphenol was replaced with 4-(trans-4-pentylcyclohexyl)phenol. The anthraquinone derivative of Test Example 6-11 is a compound represented by the following formula (P6-11).

[0406] [ka]

[0407] (Test Example 6-12) <Synthesis of precursor D4> Precursor D4 was obtained in the same manner as in Example 4, except that precursor B4 was replaced with precursor A1 in the synthesis process of precursor B11. Precursor D4 is a compound represented by the following formula (6-b).

[0408] [ka]

[0409] <Synthesis of dyes in Test Examples 6-12> The anthraquinone derivatives of Test Examples 6-12 were obtained by synthesizing the dyes of Test Examples 4-10 of the fourth embodiment in the same manner as above, except that precursor D1 was replaced with precursor D4 and 4-methoxybenzenethiol was replaced with 4-heptyloxybenzenethiol. The anthraquinone derivatives of Test Examples 6-12 are compounds represented by the following formula (P6-12).

[0410] [ka]

[0411] (Test Example 6-13) <Synthesis of dyes in Test Examples 6-13> The anthraquinone derivative of Test Example 6-13 was obtained by synthesizing the dye of Test Example 4-13 of the fourth embodiment in the same manner as above, except that 4-heptyloxyphenol was replaced with 4-monobutylaminophenol. The anthraquinone derivative of Test Example 6-13 is a compound represented by the following formula (P6-13). Note that the anthraquinone derivative of Test Example 6-13 is the same compound as the anthraquinone derivative of Test Example 1-13.

[0412] [ka]

[0413] (Evaluation method) <Evaluation of absorption wavelength and coloring strength> For the anthraquinone derivatives of Test Examples 6-1 to 6-13, evaluation specimens were prepared in the same manner as in the first example.

[0414] The ultraviolet-visible absorption spectrum of the evaluation test piece of each test example was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.) and the maximum absorption wavelength λmax and the absorbance at that wavelength were determined for the wavelength range of 360 nm to 800 nm. In the evaluation of coloring strength, an absorbance of 0.40 or more was rated as good (◯), and an absorbance of less than 0.40 was rated as poor (×).

[0415] <Calculation of transition dipole moment> The transition dipole moments of the anthraquinone derivatives of Test Examples 6-1 to 6-13 were calculated using the time-dependent density functional method. Specifically, the quantum chemistry calculation program GAMESS was used, with the functional set to B3LYP and the basis function set to 6-31G(d), to calculate the transition dipole moment of each anthraquinone derivative in vacuum. The transition dipole moment is a vector consisting of x, y, and z components. The value obtained by raising the sum of the squares of each component to the 1 / 2 power was used as the magnitude μ(μ=(x 2 +y 2 +z 2 ) 1 / 2 ) was decided.

[0416] (Evaluation results) Table 6 shows the structure of the anthraquinone derivative, each component of the transition dipole moment, the magnitude μ of the transition dipole moment, the maximum absorption wavelength λmax, the absorbance, and the evaluation results of the coloring strength for Test Examples 6-1 to 6-13. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (II), and R, A, X, and Y in Table 6 are 1 ,Y 2 , Z are R, A, X, and Y in the following formula (II). 1 ,Y 2 , which corresponds to Z.

[0417] [ka]

[0418] [Table 6]

[0419] As shown in Table 6, Test Examples 6-1 to 6-10, in which the magnitude μ of the transition dipole moment was 3.30 D or more, exhibited higher absorbance and better tinting strength than Test Examples 6-11 to 6-13, in which the magnitude μ of the transition dipole moment was less than 3.30 D. Furthermore, the anthraquinone derivatives of Test Examples 6-1 to 6-10 tended to have high absorption maximum wavelengths in the wavelength range of 580 nm or more, making them usable as cyan dyes.

[0420] The results in Table 6 suggest that the direct bonding of a substituent to the β-position increases the transition dipole moment. 1 ,Y 2 It was confirmed that when the group is an electron-donating group such as an alkylamino group, the transition dipole moment becomes large and high absorbance tends to be obtained.

[0421] Seventh Example: Test Example Corresponding to the Seventh Embodiment In the seventh example, synthesis was carried out using the same precursor as in the first to sixth examples.

[0422] (Test Example 7-1) The dye of Test Example 1-11 in the first embodiment was the anthraquinone derivative of Test Example 7-1, which is a compound represented by the following formula (P7-1).

[0423] [ka]

[0424] (Test Example 7-2) The dye of Test Example 2-8 in the second embodiment was the anthraquinone derivative of Test Example 7-2, which is a compound represented by the following formula (P7-2).

[0425] [ka]

[0426] (Test Example 7-3) The dye of Test Example 1-3 in Example 1 was replaced with the anthraquinone derivative of Test Example 7-3, which is a compound represented by the following formula (P7-3).

[0427] [ka]

[0428] (Test Example 7-4) The dye of Test Example 1-2 in Example 1 was replaced with the anthraquinone derivative of Test Example 7-4, which is a compound represented by the following formula (P7-4).

[0429] [ka]

[0430] (Test Example 7-5) <Synthesis of precursor A4> Precursor A4 was obtained in the same manner as in Example 1, except that 4-cyanoaniline was used instead of 4-heptylaniline in the synthesis of precursor A2. Precursor A4 is a compound represented by the following formula (7-a).

[0431] [ka]

[0432] <Synthesis of dye of Test Example 7-5> The anthraquinone derivative of Test Example 7-5 was obtained by the same synthesis as in Test Example 1-1 of the first embodiment, except that precursor A2 was changed to precursor A4 and 4-dimethylaminophenylboronic acid was changed to 4-heptyloxyphenylboronic acid. The anthraquinone derivative of Test Example 7-5 is a compound represented by the following formula (P7-5).

[0433] [ka]

[0434] (Test Example 7-6) <Synthesis of dye of Test Example 7-6> The anthraquinone derivative of Test Example 7-6 was obtained by synthesizing the dye of Test Example 1-1 of the first embodiment in the same manner as above, except that precursor A2 was changed to precursor A4 and 4-dimethylaminophenylboronic acid was changed to 4-pentylcyclohexylphenylboronic acid. The anthraquinone derivative of Test Example 7-6 is a compound represented by the following formula (P7-6). Note that the anthraquinone derivative of Test Example 7-6 is the same compound as the anthraquinone derivative of Test Example 2-3.

[0435] [ka]

[0436] (Test Example 7-7) The dye of Test Example 5-5 in the fifth embodiment was replaced with the anthraquinone derivative of Test Example 7-7. The anthraquinone derivative of Test Example 7-7 is a compound represented by the following formula (P7-7).

[0437] [ka]

[0438] (Test Examples 7-8) The dye of Test Example 5-7 in the fifth embodiment was replaced with the anthraquinone derivative of Test Example 7-8, which is a compound represented by the following formula (P7-8).

[0439] [ka]

[0440] (Test Examples 7-9) <Synthesis of dyes in Test Examples 7-9> The anthraquinone derivatives of Test Examples 7-9 were obtained by synthesizing the dyes of Test Examples 4-10 of the fourth embodiment in the same manner as above, except that precursor D1 was changed to precursor D3 and 4-methoxybenzenethiol was changed to 4-heptyloxybenzenethiol. The anthraquinone derivatives of Test Examples 7-9 are compounds represented by the following formula (P7-9).

[0441] [ka]

[0442] (Test Examples 7-10) <Synthesis of dyes in Test Examples 7-10> The anthraquinone derivatives of Test Examples 7-10 were obtained by synthesizing the dyes of Test Examples 4-13 of the fourth embodiment in the same manner as above, except that precursor A2 was replaced with precursor A3. The anthraquinone derivatives of Test Examples 7-10 are compounds represented by the following formula (P7-10). The anthraquinone derivatives of Test Examples 7-10 are the same compounds as the anthraquinone derivatives of Test Examples 1-12.

[0443] [ka]

[0444] (Test Examples 7-11) The dye of Test Examples 6-11 in Example 6 was the anthraquinone derivative of Test Examples 7-11. The anthraquinone derivative of Test Examples 7-11 is a compound represented by the following formula (P7-11).

[0445] [ka]

[0446] (Test Examples 7-12) The dye of Test Examples 6-12 in Example 6 was the anthraquinone derivative of Test Examples 7 to 12. The anthraquinone derivative of Test Examples 7-12 is a compound represented by the following formula (P7-12).

[0447] [ka]

[0448] (Test Example 7-13) <Synthesis of precursor D5> Precursor D5 was obtained in the same manner as in Example 4, except that in the synthesis process of precursor B11, precursor B4 was replaced with precursor A1 and 4-heptyloxyphenol was replaced with 4-pentylcyclohexylphenol. Precursor D5 is a compound represented by the following formula (7-b).

[0449] [ka]

[0450] <Synthesis of dyes in Test Examples 7-13> The anthraquinone derivatives of Test Examples 7-13 were obtained by synthesizing the dyes of Test Examples 4-10 of the fourth embodiment in the same manner as above, except that precursor D1 was replaced with precursor D5 and 4-methoxybenzenethiol was replaced with 4-heptyloxybenzenethiol. The anthraquinone derivatives of Test Examples 7-13 are compounds represented by the following formula (P7-13).

[0451] [ka]

[0452] (Evaluation method) <Evaluation of absorption wavelength and coloring strength> For the anthraquinone derivatives of Test Examples 7-1 to 7-13, evaluation specimens were prepared in the same manner as in Example 1. Then, the maximum absorption wavelength λmax and the absorbance at that wavelength were determined in the same manner as in Example 6, and the coloring strength was evaluated.

[0453] <Calculation of molecular orbital coefficients> The molecular orbital coefficients of the anthraquinone derivatives of Test Examples 7-1 to 7-13 were calculated using density functional theory. Specifically, using the quantum chemistry calculation program GAMESS, the anthraquinone derivatives were subjected to structural optimization using the functional B3LYP and the basis function 6-31G(d), and the molecular orbital coefficients of the optimized structure were obtained. C in the above formula (7-1) 11 , C 12 , C 21 , C 22 For each carbon atom in the 11 , M 12 , M 21 , M 22 Calculate 、 M 11 , M 12 , M 21 , M22 The average Mv was calculated. Under these calculation conditions, 15 orbitals are assigned to the carbon atom, and the molecular orbital coefficients are calculated for each orbital.

[0454] (Evaluation results) Table 7 shows the structure of the anthraquinone derivative, the square root of the sum of the squares of the molecular orbital coefficients, the average Mv, the maximum absorption wavelength λmax, the absorbance, and the evaluation results of the coloring strength for Test Examples 7-1 to 7-13. The structure of the anthraquinone derivative of each Test Example is represented by the following formula (II), and R, A, X, and Y in Table 7 are 1 ,Y 2 , Z are R, A, X, and Y in the following formula (II). 1 ,Y 2 , which corresponds to Z.

[0455] [ka]

[0456] [Table 7]

[0457] As shown in Table 7, Test Examples 7-1 to 7-9, which have an average Mv of 0.03 or more, have higher absorbance and better tinting strength than Test Examples 7-10 to 7-13, which have an average Mv of less than 0.03. Furthermore, the anthraquinone derivatives of Test Examples 7-1 to 7-9 have absorption maxima in the wavelength range of 580 nm or more, and therefore can be used as cyan dyes.

[0458] The results in Table 7 suggest that the average Mv increases when a substituent is directly bonded to the β-position. Furthermore, a comparison between Test Example 7-1 and Test Example 7-5, and a comparison between Test Example 7-2 and Test Example 7-6 confirmed that when Z is an electron-withdrawing group such as a cyano group, the average Mv increases and a high absorbance tends to be obtained. Furthermore, Test Examples 7-3, 7-4, and 7-9 show that when Y 1 ,Y 2It was confirmed that when is an electron-donating group such as an alkylamino group, the average Mv tends to be large and high absorbance tends to be obtained.

Claims

1. An anthraquinone derivative represented by the following formula (1-1): 【Chemical 1】 In formula (1-1), R １ , R ２ , and R ３ are each independently an amino group or a hydroxyl group, and R １ , R ２ , and R ３ At least one of Y is a hydroxyl group. １ and Y ２ at least one of Y is an electron-donating group, and the electron-donating group is an alkylamino group, an amino group, or a piperidyl group; １ and Y ２ When only one of Y １ and Y ２ the other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, or a cyclohexyl group, and the aryl group and cyclohexyl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

2. An anthraquinone derivative represented by the following formula (1-1): 【Chemistry 2】 In formula (1-1), R １ , R ２ , and R ３ are each independently an amino group or a hydroxyl group. １ and Y ２ at least one of Y is an electron-donating group, and the electron-donating group is an acetamide group or a hydroxyl group; １ and Y ２ When only one of Y １ and Y ２ the other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, or a cyclohexyl group, and the aryl group and cyclohexyl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

3. In the formula (1-1), R １ and R ３ each is a hydroxyl group, and R ２ is an amino group The anthraquinone derivative according to claim 1 or 2.

4. An anthraquinone derivative represented by the following formula (2-1): 【Chemistry 3】 In formula (2-1), R １ , R ２ , and R ３ are each independently an amino group or a hydroxyl group, and R １ , R ２ , and R ３ At least one of Y is a hydroxyl group. １ and Y ２ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, an alkylamino group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. Z is an electron-withdrawing group, and the electron-withdrawing group is a cyano group or a halogenated alkyl group.

5. An anthraquinone derivative represented by the following formula (2-1): 【Chemistry 4】 In formula (2-1), R １ , R ２ , and R ３ are each independently an amino group or a hydroxyl group. １ and Y ２ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, an alkylamino group, or a cyclohexyl group, and the aryl group and the cyclohexyl group may have a substituent. Z is an electron-withdrawing group, and the electron-withdrawing group is an aldehyde group, an acetyl group, or a sulfo group.

6. In the formula (2-1), R １ and R ３ each is a hydroxyl group, and R ２ is an amino group The anthraquinone derivative according to claim 4 or 5.

7. The anthraquinone derivative according to claim 6, which is derived from claim 4, is represented by the following formula (2-3): 【Chemistry 5】 In formula (2-3), R ４ and R ５ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group, and Z is the electron-withdrawing group. Anthraquinone derivatives.

8. The anthraquinone derivative according to claim 6, which is derived from claim 5, is represented by the following formula (2-3): 【Chemistry 6】 In formula (2-3), R ４ and R ５ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group, and Z is the electron-withdrawing group. Anthraquinone derivatives.

9. An anthraquinone derivative represented by the following formula (3-1): 【Chemistry 7】 In formula (3-1), R １ , R ２ , and R ３ are each independently an amino group or a hydroxyl group, and R １ , R ２ , and R ３ At least one of Y is a hydroxyl group. １ and Y ２ At least one of Y is a cyclohexyl group, and the cyclohexyl group may have a substituent; １ and Y ２ When only one of Y is a cyclohexyl group, １ and Y ２ the other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group, and the aryl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

10. The anthraquinone derivative according to claim 9, represented by the following formula (3-2): 【Chemistry 8】 In formula (3-2), Y １ and Y ２ At least one of Y is a cyclohexyl group, and the cyclohexyl group may have a substituent; １ and Y ２ When only one of Y is a cyclohexyl group, １ and Y ２ the other is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group, and the aryl group may have a substituent. Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

11. The anthraquinone derivative according to claim 10, represented by the following formula (3-3): 【Chemistry 9】 In formula (3-3), R ４ and R ５ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cyclic hydrocarbon group, and Z is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a cyano group, a nitro group, a halogen atom, an amino group, or an alkylamino group.

Images