JP5652823B2 - Azo compounds - Google Patents

Description

  The present invention relates to an azo compound. More specifically, the present invention relates to an azo compound having excellent heat resistance.

  Dyes have long been used as dyes for dyeing various fibers. In recent years, ink sheets for inkjet inks, synthetic resin and dyes for synthetic fiber materials, colorants for polymer materials, and thermal transfer type image forming materials have been used. It is used in various fields such as toner for electrophotography, magnetic recording material, and optical recording material. For this reason, the development of dyes that combine these performances is desired, including the performance required of dyes, not only for color development but also for light resistance, heat resistance, solubility in solvents, and compatibility with resins. .

  For example, pyridone azo compounds are known as yellow dyes (see, for example, Patent Documents 1 to 3).

JP-A 61-159594 JP 2006-71822 A JP 2009-299030 A

  When dyes are used in inkjet ink applications, the performance required of the dyes has been mainly soluble in solvents, but in recent years, when printing materials are processed at high temperatures after inkjet printing (for example, in food containers) There is a growing need for heat resistance that is difficult to discolor even when the food container is heat sterilized after inkjet printing.

  However, the conventional pyridone azo compounds described in Patent Documents 1 to 3 have a drawback that they are poor in heat resistance as compared with phthalocyanine dyes and azo metal complex dyes. Therefore, development of pyridone azo compounds with improved heat resistance has been desired.

  Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a yellow dye having excellent heat resistance.

  The present inventor has intensively studied to solve the above problems. As a result, it was found that a dimer-type azo compound in which two pyridone azo skeletons are linked to one molecule of an alkylene group having a cyclic saturated hydrocarbon group via a sulfonamide bond exhibits excellent heat resistance, The present invention has been completed.

  That is, the above-described purpose is represented by the following chemical formula 1:

In the chemical formula 1, R ¹ and R ² each independently represent a linear or branched alkyl group having 1 to 16 carbon atoms or a substituent containing a hetero atom; R ³ and R ⁴ are each independently A linear, branched or cyclic alkyl group having 1 to 8 carbon atoms or a halogenated alkyl group having 1 to 8 carbon atoms; R ⁵ and R ⁶ are each independently 1 Represents a linear or branched alkyl group of ˜8 or a halogen atom; X represents a substituted or unsubstituted cycloalkylene group having 5 to 12 carbon atoms, wherein the substituent is a carbon number Selected from the group consisting of 1-8 linear or branched alkyl groups, halogen atoms, and substituents containing heteroatoms; m and n are each independently an integer of 0-3; and p And q are each independently an integer of 0-4. In which, in shown,
In the chemical formula 1, — (CH ₂ ) _m —X— (CH ₂ ) _n — represents the following chemical formula 2:
In the chemical formula 2, r is an integer of 0 to 5.
It is achieved by Ah Ru azo compound with a group selected from the group consisting of.

  The azo compound of the present invention can exhibit excellent heat resistance.

  According to the present invention, the following chemical formula 1:

The azo compound shown by these is provided. The azo compound of the present invention is an alkylene group having a cyclic saturated hydrocarbon group (in Formula 1, — (CH ₂ ) _m —X— (CH ₂ ) _n —) having two pyridone azo skeletons in one molecule. It is a dimer-type azo compound linked via (—NH—SO ₂ — in Chemical Formula 1). By using a dimer type having such a specific structure, the azo compound exhibits excellent heat resistance (for example, the weight reduction rate of the azo compound is reduced when the azo compound is held at 230 ° C. or higher). To do. In addition, the azo compound of the present invention has excellent solubility in solvents, particularly solvents such as cyclohexanone (CHN) and N-methylpyrrolidone (NMP) (in the present specification, it is also simply referred to as “solvent solubility”). Have Therefore, the azo compound of the present invention can be suitably used for applications such as inkjet inks.

  Hereinafter, preferred embodiments of the present invention will be described. The azo compound of the present invention is represented by the following chemical formula 1.

In the chemical formula 1, R ¹ and R ² each independently represent a linear or branched alkyl group having 1 to 16 carbon atoms or a substituent containing a hetero atom.

  Here, the linear, branched or cyclic alkyl group having 1 to 16 carbon atoms is not particularly limited. Specific examples of such alkyl groups include methyl, ethyl, propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, n-pentyl group, isopentyl group, neopentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group, n-octyl group, 2-ethylhexyl group, nonyl group, decyl group, undecyl group, Examples include dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group and the like. Among these, in consideration of solvent solubility such as heat resistance and solvent solubility, a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms is preferable, and propyl group, isopropyl group, cyclopropyl group, n -Butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, neopentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group N-octyl group and 2-ethylhexyl group are more preferable.

  The substituent containing a hetero atom is not particularly limited as long as it is derived from an amine having a hetero atom (for example, an oxygen atom, a nitrogen atom, or a sulfur atom) that can be used for pyridone ring synthesis. Main examples include hydroxyalkyl group, hydroxyalkoxyalkyl group, alkoxyalkyl group, aryloxyalkyl group, aminoalkyl group, mercaptoalkyl group, alkylthioalkyl group, oxygen atom, nitrogen atom, sulfur atom, etc. as hetero atoms. Examples of the substituent include. In the azo compound of the present invention, any of these substituents containing an oxygen atom, a nitrogen atom, a sulfur atom, etc. contributes to further improving the solvent solubility without adversely affecting the heat resistance and color tone. sell. The number of carbon atoms contained in the substituent containing a hetero atom is not particularly limited, but 0 to 16 is preferable and 1 to 12 is more preferable in consideration of solvent solubility, heat resistance and the like, particularly solvent solubility. 2 to 10 are more preferable.

  Specific examples of the substituent containing a hetero atom include a hydroxyethyl group, a hydroxypropyl group, a 4-hydroxybutyl group, a 2-hydroxy-1-methyl-ethyl group, a hydroxyethoxyethyl group, a 2-methoxyethyl group, 3-methoxypropyl group, 3-ethoxypropyl group, 3-butoxypropyl group, 3-isopropoxypropyl group, 2-methoxy-1-methyl-ethyl group, tetrahydrofurfuryl group, 2-phenoxyethyl group, 2- ( 4-methoxyphenoxy) ethyl group, 3-N-morpholinopropyl group, 2-N-morpholinoethyl group, 3-N-pyrrolidinonylpropyl group, 2-dimethylaminoethyl group, 3-dimethylaminopropyl group, 3- Diethylaminopropyl group, 2-N-pyrrolidinylethyl group, 2- (N-methyl-2-pyrrolidinyl group) ) Ethyl group, 2-N-piperidinylethyl group, 3- (2-methyl -N- piperidinyl) propyl group, mercaptoethyl group, 2- (ethylthio) ethyl group, and the like are preferable.

In Formula 1, R ³ and R ⁴ each independently represent a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or a halogenated alkyl group having 1 to 8 carbon atoms. .

  Here, the linear or branched alkyl group having 1 to 8 carbon atoms is not particularly limited. Specifically, methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, Neopentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group, n-octyl group, 2-ethylhexyl group and the like can be mentioned. Among these, in consideration of solvent solubility, such as heat resistance and solvent solubility, a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms is preferable, methyl group, ethyl group, propyl group, isopropyl group, A cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, neopentyl group, cyclopentyl group, n-hexyl group, and cyclohexyl group are more preferable.

  The halogenated alkyl group having 1 to 8 carbon atoms is obtained by halogenating a part of a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. Such a halogenated alkyl group is not particularly limited, and specifically includes a chloromethyl group, a bromomethyl group, a trifluoromethyl group, a chloroethyl group, a 2,2,2-trichloroethyl group, a bromoethyl group, a chloropropyl group. And bromopropyl group. Of these, chloromethyl group, trichloromethyl group, and bromomethyl group are preferable in consideration of heat resistance such as heat resistance and solvent solubility.

In Chemical Formula 1, R ⁵ and R ⁶ each independently represent a linear or branched alkyl group having 1 to 8 carbon atoms or a halogen atom. Here, the plurality of R ⁵ and R ⁶ may be the same or different.

  Here, the linear or branched alkyl group having 1 to 8 carbon atoms is not particularly limited. Specifically, methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, Neopentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group, n-octyl group, 2-ethylhexyl group and the like can be mentioned. Among these, in consideration of solvent solubility, such as heat resistance and solvent solubility, a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms is preferable, methyl group, ethyl group, propyl group, isopropyl group, A cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, and cyclobutyl group are more preferable.

  Although it does not restrict | limit especially as a halogen atom, A fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned. Of these, fluorine atoms are preferred in view of solvent solubility, such as heat resistance and solvent solubility.

Further, in the above Formula 1, p and q are, respectively, represent the number of bonds of ^{R 5} and ^{R 6} on the benzene ring and is an integer of 0-4. When p or q is 0 to 3, a hydrogen atom is bonded to the carbon atom on the benzene ring to which R ⁵ or R ⁶ and the sulfonyl group (—SO ₂ —) are not bonded. Among these, p and q are preferably 0 to 2 in consideration of solvent solubility such as heat resistance and solvent solubility. Note that p and q may be the same or different.

  In the chemical formula 1, X represents a substituted or unsubstituted cycloalkylene group having 5 to 12 carbon atoms. In this case, the substituent is selected from the group consisting of a linear or branched alkyl group having 1 to 8 carbon atoms, a halogen atom, and a substituent containing a hetero atom.

  Here, the C5-C12 cycloalkylene group is not particularly limited. Specific examples include a cyclopentylene group, a cyclohexylene group, a cycloheptylene group, a cyclooctylene group, and the like. Among these, in view of heat resistance such as heat resistance and solvent solubility, a cyclopentylene group, a cyclohexylene group, and the like are preferable, and a cyclohexylene group is more preferable.

In Chemical Formula 1, — (CH ₂ ) _m — and (CH ₂ ) _n — are bonded to X, but the bonding position is not particularly limited. - _{(CH 2) m} - coupling position 1-position and the case - _{(CH 2) m} - and _{(CH 2) n} - bond position of, for example, when X is cyclopentylene group 1, 2nd, 1st and 3rd positions; when X is a cyclohexylene group, 1st, 2nd, 1st, 3rd, 1st and 4th positions; 1, 4 position; when X is a cyclooctylene group, it may be any of 1, 2 position, 1, 3 position, 1, 4 position, 1, 5 position;

In addition, in — (CH ₂ ) _m —X— (CH ₂ ) _n — in Chemical Formula 1, the configuration of — (CH ₂ ) _m — and (CH ₂ ) _n — bonded to X is particularly limited. However, it may be either a cis isomer, a trans isomer, or a mixture thereof, but by using a mixture of a cis isomer and a trans isomer, an azo compound having further excellent heat resistance and solvent solubility ( A composition containing geometrical isomers of cis and trans isomers).

  The linear or branched alkyl group having 1 to 8 carbon atoms optionally present in the above cycloalkyl group having 5 to 12 carbon atoms is not particularly limited. Specifically, methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, Neopentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, n-heptyl group, cycloheptyl group, n-octyl group, 2-ethylhexyl group and the like can be mentioned. Among these, in view of solvent solubility, such as heat resistance and solvent solubility, a linear alkyl group having 1 to 6 carbon atoms is preferable, methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, n -Butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, neopentyl group, cyclopentyl group, n-hexyl group, and cyclohexyl group are more preferable.

  Although there is no restriction | limiting in particular as a halogen atom which may exist in the said C5-C12 cycloalkylene group, A fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned. Of these, fluorine atoms are preferred in view of heat resistance such as heat resistance and solvent solubility.

  Examples of the substituent containing a hetero atom optionally present in the cycloalkylene group having 5 to 12 carbon atoms include an acyl group, an alkoxy group, a nitro group, an amino group, an alkylamino group, an alkylcarbonylamino group, Heteroaryl such as arylamino group, arylcarbonylamino group, carbonyl group, alkoxyalkyl group, alkoxycarbonyl group, alkylaminocarbonyl group, alkoxysulfonyl group, alkylthio group, carbamoyl group, aryloxycarbonyl group, oxyalkylether group, cyano group Although the substituent which contains an oxygen atom, a nitrogen atom, a sulfur atom, etc. can be illustrated as an atom, it is not limited to these. The number of carbon atoms contained in the substituent containing a hetero atom is not particularly limited, but 0 to 16 is preferable and 1 to 12 is more preferable in consideration of solvent solubility, heat resistance and the like, particularly solvent solubility. 2 to 10 are more preferable. Some of the above substituents are shown below with more specific examples.

  Examples of the acyl group include an acetyl group, an ethylcarbonyl group, a propylcarbonyl group, a butylcarbonyl group, a pentylcarbonyl group, a hexylcarbonyl group, a benzoyl group, and a pt-butylbenzoyl group. Among these, an acetyl group, an ethylcarbonyl group, a propylcarbonyl group, a benzoyl group, and a pt-butylbenzoyl group are preferable.

  The alkoxy group is a straight chain or branched chain having 1 to 8 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a 2-ethylhexyloxy group, and an octyloxy group. And an alkoxy group of the chain. Among these, in consideration of solvent solubility such as heat resistance and solvent solubility, a straight-chain alkoxy group having 1 to 6 carbon atoms is preferable, and methoxy group, ethoxy group, propoxy group, isopropoxy group, butoxy group, pentyl An oxy group and a hexyloxy group are more preferable.

  Examples of the alkylamino group include methylamino group, ethylamino group, n-propylamino group, n-butylamino group, sec-butylamino group, n-pentylamino group, n-hexylamino group, n-heptylamino group, An n-octylamino group, a 2-ethylhexylamino group, etc. are mentioned. Among these, a methylamino group, an ethylamino group, an n-propylamino group, an n-butylamino group, a sec-butylamino group, and a 2-ethylhexylamino group are preferable.

  As the alkoxyalkyl group, methoxymethyl group, methoxyethyl group, methoxypentyl group, methoxyhexyl group, methoxyheptyl group, ethoxyethyl group, ethoxypentyl group, ethoxyhexyl group, propoxyethyl group, propoxypropyl group, propoxybutyl group, Examples thereof include a propoxypentyl group, a butoxyethyl group, a butoxypropyl group, a butoxybutyl group, a 3-methoxypropyl group, and a 3-ethoxypropyl group. Among these, a methoxymethyl group, a methoxyethyl group, a methoxypentyl group, an ethoxyethyl group, a propoxyethyl group, a propoxypropyl group, a butoxyethyl group, a 3-methoxypropyl group, and a 3-ethoxypropyl group are preferable.

  Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, an n-propoxycarbonyl group, an isopropoxycarbonyl group, an n-butoxycarbonyl group, an isobutoxycarbonyl group, a sec-butoxycarbonyl group, and a tert-butoxycarbonyl group. It is done. Of these, a methoxycarbonyl group, an ethoxycarbonyl group, an n-propoxycarbonyl group, and an isopropoxycarbonyl group are preferable.

  In addition to those exemplified above, examples of the substituent containing a hetero atom optionally present in a cycloalkylene group having 5 to 12 carbon atoms include 3-N-morpholinopropyl group, 2-N-morpholinoethyl group, 3-N— Pyrrolidinonylpropyl group, 2-dimethylaminoethyl group, 3-dimethylaminopropyl group, 3-diethylaminopropyl group, 2-N-pyrrolidinylethyl group, 2- (N-methyl-2-pyrrolidinyl) ethyl group, 2-N-piperidinylethyl group, 3- (2-methyl-N-piperidinyl) propyl group, 3-isopropoxypropyl group and the like may be used. Among these, 3-N-morpholinopropyl group, 2-N-morpholinoethyl group, 3-N-pyrrolidinonylpropyl group, 2- (N-methyl-2-pyrrolidinyl) ethyl group, 2-N-piperidinyl An ethyl group and a 3- (2-methyl-N-piperidinyl) propyl group are preferable.

  In addition, a plurality of the above substituents can be substituted on the cycloalkylene group, and the types of these substituents may be the same or different when a plurality of substituents are substituted.

  In Chemical Formula 1, m and n are each independently an integer of 0 to 3. Among these, in consideration of solvent solubility such as heat resistance and solvent solubility, m and n are preferably 0 to 2, more preferably 0 to 1, and further preferably m = 0, n. = 1, or a combination of m = 1 and n = 1.

In order to exhibit excellent heat resistance and solvent solubility, the azo compound of the present invention must have the above-described chemical formula 1, but — (CH ₂ ) _m —X— (CH _{2 in the} chemical formula 1 ) _N- is a specific structure, that is, in Formula 1, X represents a substituted or unsubstituted cyclohexylene group, wherein the substituent is linear or branched having 1 to 8 carbon atoms It is preferably selected from the group consisting of chain alkyl groups; m and n are preferably integers of 0-2.

_{Furthermore, - (CH 2) m -X-} (CH 2) n - is the following chemical formula 2:

More preferably a group selected from the group consisting _{of, - (CH 2) m -X-} (CH 2) n - is represented by the following chemical formula 3:

More preferably, the group is selected from the group consisting of: Azo compounds of the present _{invention, - (CH 2) m -X-} (CH 2) n - is by having the above structure, it is possible to exert more remarkable heat resistance, solvent solubility.

In the above chemical formula 1, the bonding position of the aminosulfonyl group (—SO ₂ —NH—) substituted on the benzene ring is either the 2-position, the 3-position or the 4-position when the azo group is bonded to the 1-position. However, the 2nd or 4th position is preferable, and the 4th position is more preferable.

  The production method of the azo compound (dimer type pyridone compound) of the present invention is not particularly limited, and a conventionally known method can be appropriately used. Hereinafter, the preferable manufacturing method of the azo compound of this invention is demonstrated. However, the present invention is not limited to the following form.

  One form (first production method) of the production method of the azo compound (dimer type pyridone compound) of the present invention is represented by the following chemical formula 4:

In the above chemical formula 4, R ⁵ , R ⁶ , p, and q are the same as defined in the above chemical formula 1; sulfanilic acid (also simply referred to as “sulfanilic acid” in the present specification) in the presence of a nitrosating agent. The diazo compound obtained by diazotization is converted into the following chemical formula 5:

In the above chemical formula 5, R ¹ , R ² , R ³ , and R ⁴ are the same as defined in the above chemical formula 1; 3-cyano-6-hydroxypyridin-2 (1H) -one compound (in the present specification) Then, it is simply referred to as “pyridone”). Thereafter, the obtained azo compound intermediate was converted from sulfonic acid (—SO ₃ H) to sulfonyl chloride (—SO ₂ Cl) using a chlorinating agent, and the following chemical formula 6:

In the above chemical formula 6, X, m and n are the same as defined in the above chemical formula 1; the reaction is carried out by reacting with a diamine (sulfonamidation reaction).

  In the above method, the diazotization reaction is not particularly limited and may be performed in the absence of a solvent or in a solvent, but is preferably performed in a solvent. In this case, as a solvent that can be used, an acidic solvent is preferably used, and more specifically, acetic acid, propionic acid, hydrochloric acid, sulfuric acid, concentrated sulfuric acid and the like can be mentioned. The said solvent may be used independently or may be used with the form of a 2 or more types of mixture, or may be used with the form of the mixture with other solvents, such as water and methanol. The amount of the solvent to be used when the solvent is used is not particularly limited, but is an amount such that the concentration of sulfanilic acid is preferably 1 to 40% by weight. Moreover, it is preferable that the sulfanilic acid (preferably in the form of a solution) of Formula 4 is cooled to about −10 to 10 ° C. Thereby, the diazonium produced | generated by subsequent reaction may be stable.

  The diazotization reaction is performed in the presence of a nitrosating agent. Here, the nitrosating agent is not particularly limited, and a known nitrosating agent can be used. Specific examples include nitrosylsulfuric acid, sodium nitrite, methyl nitrite and the like. The amount of the nitrosating agent used when the nitrosating agent is used is not particularly limited, but it is preferably 1 to 2 mol per 1 mol of sulfanilic acid. The nitrosating agent may be added as it is, but may be diluted with water or methanol.

  The diazotization reaction conditions are not particularly limited as long as the diazotization reaction of the sulfanilic acid represented by Chemical Formula 4 proceeds to obtain a desired diazo compound. Specifically, the reaction temperature is preferably −15 to 15 ° C., more preferably −10 to 10 ° C. Moreover, reaction time becomes like this. Preferably it is 0.1 to 10 hours, More preferably, it is 0.5 to 3 hours. Here, the excess nitrosating agent may be decomposed by adding sulfamic acid.

  Next, the diazonium compound thus obtained is subjected to a coupling reaction with the pyridone of the above chemical formula 5. Here, the coupling reaction is not particularly limited and may be performed in the absence of a solvent or in a solvent, but is preferably performed in a solvent. Further, when pyridone is added to the diazo compound, it may be added as it is or may be added in the form of a solution. The solvent used when added in the form of a solution is not particularly limited as long as it can dissolve or disperse pyridone. For example, water, methanol or the like is used. The said solvent may be used independently or may be used with the form of a 2 or more types of mixture. The amount of the solvent used when the solvent is used is not particularly limited, but is an amount such that the concentration of pyridone is preferably 3 to 30% by weight. In consideration of pyridone solubility, coupling reaction reactivity, and the like, the pyridone solution preferably further contains a base. In this case, examples of the base include sodium hydroxide, sodium carbonate, sodium acetate, potassium hydroxide and the like. The addition amount of the base is not particularly limited, but is preferably such an amount that the pyridone solution becomes pH 8-10.

  In the above coupling reaction, the order of addition of the diazo compound and pyridone is not particularly limited, and the diazo compound and pyridone are added simultaneously; the diazo compound is added to pyridone; and the pyridone is added to the diazo compound. There may be. Preferably, pyridone is added to the diazo compound. As a result, the exotherm is suppressed and the reaction tends to proceed cleanly. The pyridone is preferably cooled to about −10 to 10 ° C. Thereby, diazonium can be stable.

  The coupling reaction conditions are not particularly limited as long as the reaction between the diazo compound and pyridone proceeds to obtain the desired azo compound. Specifically, the reaction temperature is preferably −15 to 15 ° C., more preferably −10 to 10 ° C. Moreover, reaction time becomes like this. Preferably it is 0.1 to 30 minutes, More preferably, it is 0.5 to 20 minutes. In addition, it is particularly preferable that pyridone is added to the diazo compound (particularly dropwise) during the reaction time.

  Moreover, after completion of the coupling reaction, a desired azo compound intermediate can be precipitated by adjusting the pH of the reaction solution to 5-8. For this reason, you may adjust pH by adding sodium hydroxide, sodium carbonate, sodium acetate, sodium hydrogencarbonate, etc. as needed. The precipitate may be subjected to salting out, crystallization, filtration, washing and drying according to a conventionally known method. By such an operation, the azo compound intermediate can be obtained efficiently and with high purity.

Thereafter, the obtained sulfonic acid intermediate (—SO ₃ H) of the azo compound intermediate is converted (chlorinated) into sulfonyl chloride (—SO ₂ Cl) using a chlorinating agent. The chlorination reaction is preferably performed in the presence of a solvent. The solvent used in this case is not particularly limited as long as it can sufficiently dissolve or disperse the azo compound intermediate and the chlorinating agent. Specific examples of the solvent include acetonitrile, dimethylformamide, diethyl ether, tetrahydrofuran, dioxane, dichloroethane, chloroform, methanol, ethanol, acetone, ethyl methyl ketone, hexane, benzene, toluene, o-dichlorobenzene, aniline, and the like. . The amount of the solvent used is not particularly limited, but is such an amount that the concentration of the azo compound intermediate is preferably 1 to 30% by weight.

  There is no restriction | limiting in particular in the chlorinating agent used for chlorination reaction, A conventionally well-known chlorinating agent can be selected suitably. Specific examples of the chlorinating agent include thionyl chloride, chlorosulfonic acid, sulfuryl chloride, phosphorus trichloride, phosphorus pentachloride, phosphorus oxychloride and the like, and thionyl chloride is particularly preferable. The amount of the chlorinating agent used is not particularly limited, but is 1 to 2 mol per 1 mol of the azo compound intermediate.

  In the chlorination reaction, the order of adding the azo compound intermediate and the chlorinating agent is not particularly limited, but the chlorinating agent is preferably added (particularly dropwise) to the azo compound intermediate. By adopting such an addition order, the reaction easily proceeds cleanly. Chlorination reaction conditions are not particularly limited as long as the desired sulfonyl chloride can be obtained. Specifically, the reaction temperature is preferably 20 to 100 ° C, more preferably 30 to 70 ° C. The reaction time is preferably 0.5 to 5 hours, more preferably 1 to 3 hours. After completion of the reaction, the reaction solution is poured into water to precipitate sulfonyl chloride, and the precipitate is filtered off. Thereafter, the desired sulfonyl chloride can be obtained by drying the precipitate (in particular, drying under reduced pressure) as necessary.

  Thereafter, the obtained sulfonyl chloride is reacted with diamine to be sulfonamidated to synthesize a dimer-type azo compound. The sulfonamidation reaction is preferably performed in the presence of a solvent. The solvent used in this case is not particularly limited as long as it can sufficiently dissolve or disperse sulfonyl chloride and diamine. Specific examples of the solvent include methanol, dioxane, acetonitrile, dimethylformamide, diethyl ether, tetrahydrofuran, dichloroethane, chloroform, ethanol, acetone, ethyl methyl ketone, hexane, benzene, toluene, o-dichlorobenzene, and aniline. . The amount of the solvent used is not particularly limited, but is such an amount that the concentration of the sulfonyl chloride is preferably 1 to 30% by weight.

  The amount of diamine used in the sulfonamidation reaction is not particularly limited as long as the desired dimer-type azo compound can be obtained, but preferably 0.5 to 0.7 mol with respect to 1 mol of sulfonyl chloride. More preferably, it is 0.5-0.6 mol. With such an amount, a dimer-type azo compound can be obtained with good yield.

  Further, the sulfonamidation reaction is preferably performed in the presence of a base in order to trap the by-produced HCl. The base used in this case is not particularly limited, and specific examples include triethylamine, tripropylamine, triethanolamine, pyridine and the like, and triethylamine is particularly preferable. The amount of the base used is not particularly limited, but it is preferably 1 to 2 mol with respect to 1 mol of sulfonyl chloride.

  In the sulfonamidation reaction, the addition order of the sulfonyl chloride and diamine is not particularly limited. For example, any of the method of adding sulfonyl chloride and diamine simultaneously; The method of adding sulfonyl chloride to diamine; The method of adding diamine to sulfonyl chloride may be sufficient. Preferably, a diamine is added (particularly dropwise) to the sulfonyl chloride. By adopting such an addition order, the target product can be obtained in good yield.

  The sulfonamidation reaction conditions are not particularly limited as long as the desired sulfonamide can be obtained. Specifically, the reaction temperature is preferably 10 to 40 ° C, more preferably 15 to 30 ° C. Moreover, reaction time becomes like this. Preferably it is 0.1 to 2 hours, More preferably, it is 0.5 to 1 hour. After completion of the reaction, an aqueous hydrochloric acid solution is poured into the reaction solution to precipitate a yellow precipitate, and the precipitate is filtered off. Then, the azo compound (dimer type azo compound) of the present invention can be obtained by drying the precipitate (in particular, drying under reduced pressure) as necessary.

  In addition, another production method (second production method) of the azo compound (dimer type pyridone compound) of the present invention is represented by the following chemical formula 7:

In the chemical formula 7, R ⁵ , R ⁶ , p, and q are as defined in the chemical formula 1; p-acetylaminobenzenesulfonyl chloride represented by the following chemical formula 6:

In the above chemical formula 6, X, m and n are as defined in the above chemical formula 1; after reacting with a diamine (sulfonamidation reaction), the amide is hydrolyzed to obtain a diamine. The amine obtained by decomposition is diazotized using a nitrosating agent, and the following chemical formula 5:

In the chemical formula 6, R ¹ , R ² , R ³ and R ⁴ are the same as defined in the chemical formula 1;

  In the other production method described above, hydrolysis of the amide is performed using a conventionally known method. For the hydrolysis, an acid such as hydrochloric acid, sulfuric acid or nitric acid, or a base such as sodium hydroxide or potassium hydroxide can be used. The reaction conditions are not particularly limited, but the reaction temperature is preferably 60 to 100 ° C., and the reaction time is preferably 1 to 5 hours.

  Note that the reagents and reaction conditions used in the sulfonamidation reaction, diazotization reaction, and coupling reaction in the other production methods are the same as those in the first production method described above, and thus detailed description thereof is omitted here. To do.

  The azo compound of the present invention as described above has a maximum absorption wavelength of 420 to 440 nm and can be used as a yellow dye (yellow dye compound). In addition, the maximum absorption wavelength (λmax) of the absorption spectrum of the azo compound described above means a value measured in chloroform using an ultraviolet-visible spectrophotometer. The azo compound of the present invention is excellent in heat resistance. For example, when the azo compound is held at 230 ° C. for 1 hour, the weight reduction rate of the azo compound is preferably as low as possible, preferably 4% by weight or less, more preferably 3% by weight or less, and still more preferably 2% by weight. % Or less. The azo compound of the present invention is soluble (compatible) with a solvent, particularly cyclohexanone (CHN) or N-methylpyrrolidone (NMP), acetone, dimethylformamide, dimethyl sulfoxide, chloroform, toluene, ethyl acetate, tetrahydrofuran and the like. More preferably, and excellent solubility (compatibility) with cyclohexanone and N-methylpyrrolidone. The solvent solubility of the azo compound of the present invention is not particularly limited, and the higher the better. For example, the concentration of the azo compound relative to the amount of CHN required to dissolve the azo compound of the present invention is preferably 1% by weight or more, more preferably 5% by weight or more, and more preferably 10% by weight or more. More preferably it is. The concentration of the azo compound relative to the amount of NMP necessary for dissolving the azo compound of the present invention is preferably 7% by weight or more, more preferably 9% by weight or more, and 12% by weight or more. More preferably it is. As described above, since the azo compound of the present invention is excellent in heat resistance and solvent solubility, it can be suitably used for various applications, particularly ink jet ink.

  Hereinafter, as an application of the azo compound of the present invention, an inkjet ink will be described as an example. That is, another embodiment of the present invention is an inkjet ink containing the azo compound of the present invention.

  The inkjet ink of the present invention is the same as the conventional inkjet, such as JP 2010-195904 A, JP 2009-132812 A, and JP 11-106693 A, except that it contains the azo compound of the present invention as a pigment. It may be an ink for use.

  The composition of the inkjet ink of the present invention can be the same as a known composition except that it contains the azo compound of the present invention as a pigment. For example, the inkjet ink of the present invention contains a pigment, a resin, and a solvent.

  The ink-jet ink of the present invention must contain the azo compound of the present invention as a pigment. Here, the blending amount of the azo compound of the present invention is not particularly limited, but is preferably 1 to 40% by weight and more preferably 3 to 30% by weight with respect to the total weight of the ink. Within such a range, a printed surface with a sufficient density can be obtained, and a stable dissolved state in ink can be obtained. In addition, the azo compound of this invention may be used independently or may be used with the form of 2 or more types of mixtures.

  In addition, the inkjet ink of the present invention may be used in combination with other pigments or dyes. Other pigments or dyes are not particularly limited, and known pigments or dyes can be used. The other pigments or dyes may be used alone or in the form of a mixture of two or more.

  The resin used in the inkjet ink of the present invention is not particularly limited, and a known resin used in the inkjet ink can be used. The resin can be appropriately selected in consideration of properties such as viscosity and adhesion. Specific examples include vinyl chloride-vinyl acetate copolymer, acrylic resin, butyral resin, polyamide resin, nitrocellulose, phenol resin, xylene resin, maleic acid resin, and silicon resin. The weight average molecular weight of the resin is not particularly limited and can be appropriately selected in consideration of a desired ink viscosity and the like. Specifically, the weight average molecular weight of the resin is preferably 1000 to 40000. Within such a range, the viscosity of the ink can be adjusted to an appropriate level. Further, the blending amount of the resin (resin content of the ink) is not particularly limited, but is preferably 0.5 to 20% by weight, and more preferably 0.6 to 15% by weight with respect to the total weight of the ink. In such a range, an appropriate ink viscosity can be obtained, so that ink can be stably ejected without causing droplet ejection or direction disturbance, and adhesion to a printing medium without peeling from the printing surface. And the dye can be retained well. In addition, the said resin may be used independently or may be used with the form of a 2 or more types of mixture. Further, for the purpose of further improving properties such as viscosity and adhesion, a higher molecular weight resin may be used in combination.

  The solvent used in the inkjet ink of the present invention is not particularly limited as long as it can dissolve other components (pigment, resin, etc.). Specifically, ketone solvents such as acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, DIBK (diisobutyl ketone), cyclohexanone, N-methylpyrrolidone, DAA (diacetone alcohol); methanol, ethanol, isopropyl alcohol, butanol Alcohol solvents such as ethylene glycol monoethyl alcohol, ethylene glycol monomethyl alcohol and other alkylene glycol ether solvents; toluene, xylene and other hydrocarbon solvents; ethyl acetate, butyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether Examples thereof include ester solvents such as acetate. Of these, ketone solvents are preferable, and acetone, methyl ethyl ketone, methyl butyl ketone, cyclohexanone, and N-methylpyrrolidone are more preferable. The amount of the solvent is not particularly limited, but is preferably 0.1 to 20% by weight with respect to the total weight of the ink. If it is such a range, other components (a pigment | dye, resin, etc.) can be melt | dissolved efficiently. In addition, the said solvent may be used independently or may be used with the form of a 2 or more types of mixture.

  The ink-jet ink of the present invention may contain other additives. Here, the other additives are not particularly limited, and the additives used for the ink jet ink can be used in the same manner. For example, a conductivity adjusting agent, an amine, a dispersing agent, a polymerization inhibitor, a surface adjusting agent, a leveling agent, an ultraviolet absorber, and an antioxidant for increasing printing suitability and printed matter resistance.

  Of these, the conductivity adjusting agent is particularly effective when the ink of the present invention is used for high-speed printing by a continuous type ink jet printer. Here, it does not restrict | limit especially as an electrical conductivity regulator, A well-known electrical conductivity regulator can be used. Specific examples include potassium iodide, ammonium thiocyanate, potassium thiocyanate, and lithium nitrate. These conductivity adjusting agents are preferred because they do not show discoloration due to heat due to the residue on the printing surface. The blending amount of the conductivity adjusting agent is not particularly limited, but is preferably 0.1 to 2% by weight based on the total weight of the ink. In such a range, sufficient conductivity can be obtained, so that moderate charge deflection can be obtained, and no discoloration is induced. In addition, the said electrical conductivity modifier may be used independently or may be used with the form of 2 or more types of mixtures.

  The dispersant may be added for the purpose of improving the dispersibility of the dye and the storage stability of the ink composition. Here, it does not restrict | limit especially as a dispersing agent, A well-known dispersing agent can be used. Specifically, a hydroxyl group-containing carboxylic acid ester, a salt of a long chain polyaminoamide and a high molecular weight acid ester, a salt of a high molecular weight polycarboxylic acid, a salt of a long chain polyaminoamide and a polar acid ester, a high molecular weight unsaturated acid ester, a high Molecular copolymer, modified polyurethane, modified polyacrylate, polyether ester type anionic activator, naphthalene sulfonic acid formalin condensate salt, aromatic sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphate ester, polyoxyethylene nonyl Examples include phenyl ether and stearylamine acetate. More specifically, styrene-acrylic acid copolymer, styrene-acrylic acid-alkyl acrylate ester copolymer, styrene-maleic acid copolymer, styrene-maleic acid-acrylic acid alkyl ester copolymer, Salt: Styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid alkyl ester copolymer, salts thereof; styrene-maleic acid half ester copolymer, vinyl naphthalene-acrylic acid copolymer, vinyl naphthalene-maleic Examples include acid copolymers, styrene-maleic anhydride-maleic acid half ester copolymers, salts thereof; benzyl methacrylate-methacrylic acid copolymers, salts thereof, and the like. The blending amount of the dispersant is not particularly limited, and can be appropriately set in consideration of desired dispersibility. Specifically, the blending amount of the dispersant is preferably 0.01 to 10% by weight with respect to the total weight of the ink. If it is such a range, components, such as a pigment | dye, can be disperse | distributed favorably. In addition, the said dispersing agent may be used independently or may be used with the form of 2 or more types of mixtures.

  The polymerization inhibitor can be added for the purpose of enhancing the storage stability of the ink and the stability in the recording apparatus. Here, it does not restrict | limit especially as a polymerization inhibitor, A well-known polymerization inhibitor can be used. Specific examples include hydroquinone, p-methoxyphenol, t-butylcatechol, and di-t-butylhydroxytoluene. The blending amount of the polymerization inhibitor is not particularly limited, and can be appropriately set in consideration of desired characteristics. Specifically, the blending amount of the polymerization inhibitor is preferably 0.01 to 5% by weight with respect to the total weight of the ink. If it is such a range, sclerosis | hardenability can be maintained and the storage stability of an ink can be improved. In addition, the said polymerization inhibitor may be used independently or may be used with the form of 2 or more types of mixtures.

  The inkjet ink of the present invention can be produced by a known method. For example, the ink-jet ink of the present invention can be prepared by adding a resin to a solvent, dissolving the mixture by stirring, and then adding a dye and other additives as necessary to sufficiently dissolve the resin. If necessary, the liquid mixture thus obtained may be filtered with a filter having a pore diameter of 3 μm or less, and further 1 μm or less.

  The ink-jet ink of the present invention may be an ink used for active energy ray-curable ink jet printing. In this case, the ink-jet ink contains a dye, a polymerizable monomer, a polymerization initiator, and, if necessary, a solvent.

  Here, the pigment is the same as described above.

  The polymerizable monomer used in the inkjet ink of the above form is not particularly limited, and is an active energy ray polymerizable substance represented by the formula (1) described in JP2009-132812A, JP2010-195904A. Polymerizable monomer (A) having one triazine ring and two or more polymerizable groups described in the publication [for example, bis (acryloxyethyl) hydroxyethyl isocyanurate, tris (methacryloxyethyl) isocyanurate, tris ( Acryloxyethyl) isocyanurate, caprolactone-modified tris (acryloxyethyl) isocyanurate, etc.], benzyl (meth) acrylate, (ethoxy (or propoxy)) 2-phenoxyethyl (meth) acrylate, dicyclopentenyl (oxyethyl) ( (Meth) acrylate, Noxydiethylene glycol (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 2-ethoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, methoxydipropylene glycol (meth) Acrylate, dipropylene glycol (meth) acrylate, β-carboxylethyl (meth) acrylate, trimethylolpropane formal (meth) acrylate, isoamyl (meth) acrylate, cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (Meth) acrylate, dicyclopentanyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate 2-hydroxy-3-phenoxypropyl (meth) acrylate, 1,4-cyclohexanedimethanol (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) ) Acrylate, acryloylmorpholine, N-vinylcaprolactam, N-vinylpyrrolidone, N-vinylformamide, N-acryloyloxyethylhexahydrophthalimide and other monofunctional monomers, dimethylol-tricyclodecane di (meth) acrylate, (ethoxy ( Or propoxy)) bisphenol A di (meth) acrylate, cyclohexanedimethanol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (ethoxy (or propoxy) B) 1,6-hexanediol di (meth) acrylate, (ethoxy (or propoxy)) neopentyl glycol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, dipropylene glycol di ( (Meth) acrylate, trimethylolpropane tri (meth) acrylate, tripropylene glycol di (meth) acrylate, pentaerythritol tri (or tetra) (meth) acrylate, trimethylolpropane tri (or tetra) (meth) acrylate, tetramethylolmethane Known monomers such as polyfunctional monomers such as tri (or tetra) (meth) acrylate and dipentaerythritol hexa (meth) acrylate can be used. The polymerizable monomers may be used alone or in the form of a mixture of two or more.

  The polymerization initiator used in the inkjet ink of the above form is not particularly limited, and can be appropriately selected in consideration of the curing speed, the cured coating film properties, the coloring material, and the like. Specifically, compounds represented by formulas (8) and (10) to (13) described in JP2009-132812; benzoin isobutyl ether, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, benzyl 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, bis (2,4,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, oligo (2-hydroxy-2-methyl-1- (4 -(1-methylvinyl) phenyl) propanone), 1,2-octanedione, 1- (4- (phenylthio) 2,2- (O-benzoyloxime)) and other radical photopolymerization initiators; 1-hydroxycyclohexyl phenyl ketone, benzoin ethyl ether, benzyldimethyl ketal, 2-hydroxy-2-methyl-1-phenylpropan-1-one , And 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, etc .; benzophenone, 4-phenylbenzophenone, isophthalphenone, 4-benzoyl-4′-methyl -Hydrogen abstraction type polymerization initiators such as diphenyl sulfide. Although the compounding quantity of the said polymerization initiator is not restrict | limited in particular, It is preferable that it is 2-25 weight% with respect to a polymerizable monomer. In such a range, an appropriate curing speed (polymerization of the polymerizable monomer can be efficiently achieved), and an appropriate ink viscosity can be obtained, so that the ink can be discharged without causing droplet ejection or direction disturbance. It can be ejected stably, has excellent adhesion to the printing medium without being peeled off from the printing surface, and the dye can be held well. In addition, the said polymerization initiator may be used independently or may be used with the form of 2 or more types of mixtures. When the compounds represented by the above formulas (8) and (10) to (13) are used as a polymerization initiator, a hydrogen donor such as triethanolamine or monoethanolamine is used in combination with the polymerizable substance. May be. Thereby, the radical generating efficiency of a polymerization initiator can be improved.

  In addition to or in place of the hydrogen donor, a sensitizer may be used in combination. The sensitizer is not particularly limited, and examples thereof include trimethylamine, methyldimethanolamine, triethanolamine, p-diethylaminoacetophenone, ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, N, N-dimethyl. Examples include amines that do not cause an addition reaction with the polymerizable monomer, such as benzylamine and 4,4′-bis (diethylamino) benzophenone.

  Moreover, the ink for inkjet of the said form may contain a solvent. The solvent is not particularly limited as long as it can dissolve other components (pigment, polymerizable monomer, polymerization initiator, etc.). Specifically, ketone solvents such as acetone, methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone, DIBK (diisobutyl ketone), cyclohexanone, N-methylpyrrolidone, DAA (diacetone alcohol); ethylene glycol monomethyl ether acetate, ethylene glycol Glycol monoacetate solvents such as monoethyl ether acetate and propylene glycol monomethyl ether acetate; Glycol diacetate solvents such as ethylene glycol diacetate, diethylene glycol diacetate and propylene glycol diacetate; ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol Glycol solvents such as ethylene glycol monobutyl ether, Propylene glycol monomethyl ether, propylene glycol monobutyl ether, diethylene glycol monoethyl glycol ether solvents such as ether; methyl lactate, ethyl lactate, propyl, lactate ester solvents such as butyl lactate. Of these, ketone solvents are preferable, and acetone, methyl ethyl ketone, methyl butyl ketone, cyclohexanone, and N-methylpyrrolidone are more preferable. The amount of the solvent is not particularly limited, but is preferably 0.1 to 20% by weight with respect to the total weight of the ink. If it is such a range, other components (a pigment | dye, a polymerizable monomer, a polymerization initiator, etc.) can be dissolved efficiently. In addition, the said solvent may be used independently or may be used with the form of a 2 or more types of mixture.

  In addition, the ink jet ink of the above form may contain other additives. Here, the other additives are not particularly limited, and the additives used for the ink jet ink can be used in the same manner. For example, a conductivity adjusting agent, an amine, a dispersing agent, a polymerization inhibitor, a surface adjusting agent, a leveling agent, an ultraviolet absorber, and an antioxidant for increasing printing suitability and printed matter resistance. In addition, since these other additives are the same as the above, description is abbreviate | omitted here.

  The ink jet ink of the above form can be produced by a known method. For example, it can be prepared by thoroughly dispersing a dye, a polymerizable monomer, a polymerization initiator, and, if necessary, other additives using a normal disperser such as a sand mill. At this time, a high concentration concentrate of the dye may be prepared in advance and then diluted with a polymerizable monomer. If necessary, the dispersion thus obtained may be filtered with a filter having a pore size of 3 μm or less, and further 1 μm or less.

The usage form of the inkjet ink of the present invention is not particularly limited, and a known inkjet printing method can be applied. For example, the ink-jet ink of the present invention is supplied to a printer head of a printer for an ink-jet recording system, ejected from the printer head onto a substrate, and then irradiated with active energy rays such as ultraviolet rays and electron beams. Thereby, the ink on the printing medium is quickly cured. In addition, when irradiating an ultraviolet-ray as a light source of an active energy ray, a high pressure mercury lamp, a metal halide lamp, a low pressure mercury lamp, an ultrahigh pressure mercury lamp, an ultraviolet laser, LED, and sunlight can be used, for example. The light source is preferably selected appropriately according to the sensitivity of the polymerization initiator used. The ultraviolet intensity that can be used for curing the ink of the present invention is preferably 500 to 5,000 mW / cm ² in a wavelength region effective for curing. Such irradiation intensity does not damage the recording medium and does not induce color fading.

  The azo compound contained in the inkjet ink of the present invention is excellent in heat resistance. Therefore, even when the ink-jet ink is used for an application in which it is heat-treated after being ejected onto the printing material, the decomposition of the azo compound can be suppressed, thereby effectively preventing discoloration. be able to. Moreover, since the azo compound contained in the inkjet ink of the present invention is excellent in solvent solubility, a stable dissolved state can be maintained in the inkjet ink.

  The effects of the present invention will be described using the following examples and comparative examples. However, the technical scope of the present invention is not limited only to the following examples. In the following examples, “parts” and [%] mean parts by weight and% by weight, respectively, unless otherwise specified.

[Example 1]
A synthesis scheme of Compound 1 is shown in Chemical Formula 8 below.

(Synthesis of Compound C1)
37 g of sulfanilic acid (Compound A) was sufficiently stirred with 150 g of water and 32 g of 35% hydrochloric acid, and then diazotized with 5 g of 4N aqueous sodium nitrite solution at 5 to 10 ° C. for 180 minutes. Next, 370 g of water was added to 42 g of pyridone (Compound B1), and a solution adjusted to pH 8 with 2N sodium hydroxide was added to the diazotization solution while maintaining the temperature at 10 ° C. or lower. The pH is adjusted to 5 with sodium hydroxide to complete the coupling reaction. After completion of the reaction, 100 g of sodium chloride is used for salting out. The precipitated product is filtered off and dried to obtain an azo compound intermediate (compound C1). 60 g (yield 78%) was obtained.

(Synthesis of Compound D1)
After adding 215 g of acetonitrile and 16 g of dimethylformamide to 35 g of the azo compound intermediate (compound C1) and stirring well, 25 g of thionyl chloride was added dropwise at room temperature (25 ° C.) over 10 minutes. After completion of dropping, the mixture was stirred at 40 ° C. for 2 hours. After completion of the reaction, the reaction solution was poured into 500 g of water and the precipitate was separated by filtration. Drying under reduced pressure gave 27 g (yield 74%) of sulfonyl chloride (Compound D1).

(Synthesis of Compound 1)
47 g of sulfonyl chloride (Compound D1) was dissolved in 175 g of dioxane, and 10 g of isophoronediamine and then 30 g of triethylamine were added dropwise over 5 minutes and 10 minutes respectively while stirring at room temperature (25 ° C.). After stirring at room temperature (25 ° C.) for 1 hour, the mixture was poured into 300 g of 1M aqueous hydrochloric acid to obtain a yellow precipitate. After filtration, the precipitate was stirred and washed with 100 g of acetone and then dried to obtain 48 g (yield 95%) of Compound 1.
[Example 2]
A synthesis scheme of Compound 2 is shown in Chemical Formula 9 below.

(Synthesis of Compound F1)
50 g of p-acetylaminobenzenesulfonyl chloride (Compound E) was dissolved in 56 g of methanol, and 18 g of isophoronediamine and then 43 g of triethylamine were added dropwise over 5 minutes and 20 minutes while stirring at 0 ° C. After stirring at room temperature (25 ° C.) for 1 hour, 97 g of 35% aqueous hydrochloric acid was added, and the mixture was heated to reflux for 3 hours. After completion of the reaction, the reaction solution was poured into 1500 g of water and stirred well. The precipitate was filtered off and dried to obtain 36 g (yield 69%) of compound F1.

(Synthesis of Compound 2)
After adding 600 g of water to 30 g of compound F1 and 17 g of sodium nitrite and sufficiently stirring, diazotization was carried out at 0 to 5 ° C. for 180 minutes using 46 g of 35% aqueous hydrochloric acid. Next, a solution obtained by dissolving 12 g of sulfamic acid in 121 g of water was added thereto. 315 g of water was added to 32 g of pyridone (compound B2), and the diazonium solution was added to a solution adjusted to pH 8 with 2M sodium hydroxide while maintaining the temperature at 10 ° C. or lower and stirred. After completion of the reaction, the precipitated product was filtered off and dried to obtain 41 g (96%) of Compound 2.
[Example 3]
A synthesis scheme of Compound 3 is shown in Chemical Formula 10 below.

(Synthesis of Compound 3)
After adding 600 g of water to 30 g of compound F1 and 13 g of sodium nitrite and sufficiently stirring, diazotization was performed at 0 to 5 ° C. for 30 minutes using 46 g of 35% aqueous hydrochloric acid. Next, a solution obtained by dissolving 6 g of sulfamic acid in 61 g of water was added thereto. 446 g of water was added to 45 g of pyridone (compound B3), and the diazonium solution was added to a solution adjusted to pH 8 with 2M sodium hydroxide while maintaining the temperature at 10 ° C. or lower and stirred. After completion of the reaction, the precipitated product was filtered off and dried to obtain 55 g (86%) of Compound 2.

[Example 4]
A synthesis scheme of Compound 4 is shown in Chemical Formula 11 below.

(Synthesis of Compound 4)
After adding 112 g of water to 7 g of compound F1 and 2 g of sodium nitrite and sufficiently stirring, diazotization was performed at 0 to 5 ° C. for 60 minutes using 10 g of 35% aqueous hydrochloric acid. Next, a solution obtained by dissolving 0.6 g of sulfamic acid in 4 g of water was added thereto. 49 g of water was added to 7 g of pyridone (compound B4), and the diazonium solution was added to a solution adjusted to pH 8 with 2M sodium hydroxide while maintaining the temperature at 10 ° C. or lower and stirred. After completion of the reaction, the precipitated product was filtered off and dried to obtain 10 g (68%) of Compound 4.

[Example 5]
A synthesis scheme of compound 5 is shown in the following chemical formula 12.

(Synthesis of Compound F2)
20 g of p-acetylaminobenzenesulfonyl chloride (compound E) was dissolved in 23 g of methanol, and 6 g of 1,3-di (aminomethyl) cyclohexane and then 9 g of triethylamine were added dropwise over 2 minutes and 5 minutes, respectively, while stirring at 0 ° C. . After stirring at room temperature (25 ° C.) for 1 hour, 22 g of 35% aqueous hydrochloric acid was added, and the mixture was heated to reflux for 3 hours. After completion of the reaction, the reaction solution was poured into 200 g of water and stirred well. The precipitate was separated by filtration and dried to obtain 10 g (yield 51%) of compound F2.

(Synthesis of Compound 5)
After adding 128 g of water to 15 g of compound F2 and 7 g of sodium nitrite and sufficiently stirring, diazotization was carried out at 0 to 5 ° C. for 120 minutes using 4 g of 35% aqueous hydrochloric acid. Next, a solution obtained by dissolving 3 g of sulfamic acid in 30 g of water was added thereto. 55 g of water was added to 12 g of pyridone (compound B1), and the diazonium solution was added to a solution adjusted to pH 8 with 2M sodium hydroxide while maintaining the temperature at 10 ° C. or lower and stirred. After completion of the reaction, the precipitated product was filtered off and dried to obtain 18 g (69%) of Compound 5.

[Example 6]
A synthesis scheme of Compound 6 is shown in Chemical Formula 13 below.

(Synthesis of Compound 6)
After adding 128 g of water to 15 g of compound F2 and 7 g of sodium nitrite and sufficiently stirring, diazotization was carried out at 0 to 5 ° C. for 120 minutes using 4 g of 35% aqueous hydrochloric acid. Next, a solution obtained by dissolving 3 g of sulfamic acid in 30 g of water was added thereto. 55 g of water was added to 14 g of pyridone (compound B5), and the diazonium solution was added to a solution adjusted to pH 8 with 2M sodium hydroxide while maintaining the temperature at 10 ° C. or lower and stirred. After completion of the reaction, the precipitated product was filtered off and dried to obtain 18 g (61%) of Compound 6.

[Example 7]
A synthesis scheme of Compound 7 is shown in Chemical Formula 14 below.

(Synthesis of Compound 7)
After adding 128 g of water to 15 g of compound F2 and 7 g of sodium nitrite and sufficiently stirring, diazotization was carried out at 0 to 5 ° C. for 120 minutes using 4 g of 35% aqueous hydrochloric acid. Next, a solution obtained by dissolving 3 g of sulfamic acid in 30 g of water was added thereto. 55 g of water was added to 18 g of pyridone (compound B3), and the diazonium solution was added to a solution adjusted to pH 8 with 2M sodium hydroxide while maintaining the temperature at 10 ° C. or lower and stirred. After completion of the reaction, the precipitated product was filtered off and dried to obtain 18 g (69%) of Compound 7.
[Comparative Example 1]
A synthesis scheme of compound 8 is shown in the following chemical formula 15.

(Synthesis of Compound 8)
50 g of sulfonyl chloride (Compound D1) was dissolved in 390 g of dioxane, and 26 g of 2-ethylhexylamine and then 66 g of triethylamine were added dropwise over 5 minutes and 15 minutes respectively while stirring at room temperature (25 ° C.). After stirring at room temperature (25 ° C.) for 1 hour, the mixture was poured into 500 g of 1M aqueous hydrochloric acid solution to obtain a yellow precipitate. After completion of the reaction, the precipitated product was filtered off and dried to obtain 61 g of Compound 8 (yield 98%).
[Comparative Example 2]
A synthesis scheme of Compound 9 is shown in Chemical Formula 16 below.

(Synthesis of Compound 9)
15 g of sulfonyl chloride (Compound D1) was dissolved in 168 g of chloroform, and 3 g of hexamethylene diamine and then 6 g of triethylamine were added dropwise over 1 minute and 5 minutes, respectively, while stirring at room temperature (25 ° C.). After stirring at room temperature (25 ° C.) for 1 hour, the mixture was poured into 200 g of 1M aqueous hydrochloric acid solution to obtain a yellow precipitate. After completion of the reaction, the precipitated product was filtered off and dried to obtain 15 g (yield 78%) of Compound 9.

<Heat resistance evaluation (TG-DTA)>
10 mg each of compounds 1 to 9 obtained in Examples and Comparative Examples was heated from room temperature (25 ° C.) to 230 ° C. (heating rate: 5 ° C./min), and the weight loss rate after 1 hour was measured. The heat resistance was evaluated. A smaller value means higher heat resistance. The results are shown in Tables 1A to 1C below.

<Solubility>
The amount of solvent required to dissolve 50 mg of each of Compounds 1 to 9 obtained in Examples and Comparative Examples in cyclohexanone (CHN) or N-methylpyrrolidone (NMP) was measured. And the weight percentage of each compound amount with respect to the amount of solvent was computed, and the solubility of each compound was evaluated. Higher values mean higher compound solubility. The results are shown in Tables 1A to 1C below.

From the results of Table 1A-1C, in Examples 1-7, (in Formula _{1, - (CH 2) m} -X- (CH 2) n -) alkylene group having a saturated cyclic hydrocarbon group per molecule It was shown that a dimer-type azo compound in which two pyridone azo skeletons are linked via a sulfonamide bond (—NH—SO ₂ —) has a low TG reduction rate and excellent heat resistance. Furthermore, it was shown that the dimer-type azo compounds of Examples 1 to 7 are excellent in solubility in cyclohexanone or N-methylpyrrolidone. In particular, Examples 1 to 4 using isophorone diamine as the diamine were remarkably excellent in solvent solubility. "-" In the table represents unrated.

  On the other hand, although Comparative Example 1 having only one pyridoneazo skeleton in one molecule was excellent in solvent solubility, it was shown to be extremely inferior in heat resistance. Further, Comparative Example 2 in which two pyridone azo skeletons are connected by a linear alkyl group has improved heat resistance compared to Comparative Example 1, but still does not have sufficient heat resistance, and the solvent solubility is remarkably inferior. It was shown that.

  From the above results, it was shown that the azo compound of the present invention is excellent in heat resistance and solvent solubility and can be suitably used for applications such as inkjet inks.

Claims (4)

The following chemical formula 1:
In the chemical formula 1, R ¹ and R ² each independently represent a linear or branched alkyl group having 1 to 16 carbon atoms or a substituent containing a hetero atom;
R ³ and R ⁴ each independently represent a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms or a halogenated alkyl group having 1 to 8 carbon atoms;
R ⁵ and R ⁶ each independently represent a linear or branched alkyl group having 1 to 8 carbon atoms, or a halogen atom;
X represents a substituted or unsubstituted cycloalkylene group having 5 to 12 carbon atoms, wherein the substituent includes a linear or branched alkyl group having 1 to 8 carbon atoms, a halogen atom, and a hetero atom. Selected from the group consisting of substituents containing atoms;
m and n are each independently an integer of 0 to 3; and p and q are each independently an integer of 0 to 4,
In is shown,
In the chemical formula 1, — (CH ₂ ) _m —X— (CH ₂ ) _n — represents the following chemical formula 2:
In the chemical formula 2, r is an integer of 0 to 5.
Oh Ru azo compound with a group selected from the group consisting of. In the chemical formula 1, — (CH ₂ ) _m —X— (CH ₂ ) _n — represents the following chemical formula 3:
The azo compound according to claim 1, which is a group selected from the group consisting of: In the chemical formula 1, — (CH ₂ ) _m —X— (CH ₂ ) _n — represents the following chemical formula 4 :
Or Ranaru is a group selected from the group azo compound according to claim 2. An inkjet ink comprising the azo compound according to claim 1 .