JP4824973B2 - Pigment dispersant comprising a copolymer having an epoxy main chain and an alkyleneimine side chain - Google Patents

Description

  The present invention relates to a pigment dispersant comprising a copolymer having an epoxy resin skeleton as a main chain and a linear polymer chain having an alkyleneimine structural unit or an N-acylalkyleneimine structural unit as a side chain.

  Conventional pigment dispersants for coating compositions, including water-based ones, are used to ensure good pigment dispersibility, such as cross-linking agents, additives for grind, solvents, control agents, fillers, plasticizers, etc. In general, those requiring many components such as a wetting agent or a surfactant. In order to adjust to a fine dispersion state, the pigment is added in the presence of a pigment dispersant and various additives, and the mixture is stirred and then used to obtain a desired particle size using a ball mill, sand mill, continuous mill, or the like. It was usually performed by making it small and stably dispersing (see Patent Documents 1 and 2). However, as described above, these have had the problem that they need to be used together with many other components and that a mechanical grinding process such as a mill for a long time is necessary.

Japanese Patent Laid-Open No. 7-3186 JP-A-11-209554

  The problem to be solved by the present invention has been made in view of the above-mentioned prior art, and it is not necessary to use other components such as additives as compared with existing methods, and mechanical such as a long time mill. An object of the present invention is to provide a pigment dispersant exhibiting a good dispersion effect without undergoing a pulverizing step.

  In the present invention, by using, as a pigment dispersant, a copolymer having a main chain having an epoxy resin skeleton and a side chain having a linear polymer chain composed of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit. , Having a hydrophobic epoxy resin skeleton in the main chain and a linear polymer chain having a hydrophilic alkyleneimine structural unit or N-acylalkyleneimine structural unit in the side chain. It is possible to form nanoparticulate polymer micelles in an acidic solvent. In addition, since a linear polymer chain having a side chain alkyleneimine structural unit or an N-acylethyleneimine structural unit has a cation charge, it can neutralize anion charges existing on various pigment surfaces. It is considered that an affinity acts between the pigment dispersant of the present invention and the pigment. Furthermore, the pigment goes through a spontaneous pulverization process from tertiary particles having a large particle size to secondary particles and further to primary particles having a size of several tens of nanometers due to the dispersion power and penetrating power of the formed polymer micelles. Therefore, the polymer micelle of the nanoparticle containing the pigment can be formed and a stable dispersion state can be maintained.

  That is, the present invention is a linear polymer chain comprising a main chain having an epoxy resin skeleton and at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit and having a number average degree of polymerization of 5 to 2,000. The present invention has been completed by finding that a pigment dispersant characterized by comprising a copolymer having a side chain having a favorable dispersion effect.

  Since the pigment dispersant of the present invention has extremely good pigment dispersibility, it is possible to finely and uniformly disperse the pigment without requiring many components and without requiring a mechanical dispersion step.

  The pigment dispersant of the present invention comprises a main chain having an epoxy resin skeleton and at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit, and a linear shape having a number average degree of polymerization in the range of 5 to 2,000. It consists of a copolymer having a side chain having a polymer chain.

  The copolymer used in the present invention has an epoxy resin skeleton in the main chain structure, and a copolymer having a main chain composed of the epoxy resin skeleton is particularly preferable. As the epoxy resin skeleton, known conventional epoxy having a secondary alcohol structure such as an epoxy resin obtained from an epihalohydrin and an aromatic dihydroxy compound or an epoxy resin obtained from a diglycidyl compound and an aromatic dihydroxy compound. It is derived from resin.

  The linear polymer chain comprising at least one of the alkyleneimine structural unit or N-acylalkyleneimine structural unit constituting the side chain of the copolymer used in the present invention can be one having a range of 5 to 2000, The thing in the range of 5-200 is preferable.

  Among such copolymers, in the present invention, the formula (1)

（式（１）中、Ｘはキサンテン骨格を有する二価のフェノール残基、ビフェニレン残基、ビスフェノール残基から選ばれる二価の基であり、Ｙはアルキレンイミン構造単位又はＮ−アシルアルキレンイミン構造単位の少なくとも一種からなる数平均重合度が５〜２０００の範囲にある直鎖状ポリマー鎖を有する側鎖を表し、複数あるＹは同一でも異なっていてもよい。）
で表される構造単位（ａ１）、
式（２）

(In formula (1), X is a divalent group selected from a divalent phenol residue, a biphenylene residue, and a bisphenol residue having a xanthene skeleton, and Y is an alkyleneimine structural unit or an N-acylalkyleneimine structure. A side chain having a linear polymer chain having a number average degree of polymerization of at least one kind of unit in the range of 5 to 2,000, and a plurality of Y may be the same or different.
A structural unit (a1) represented by:
Formula (2)

（式（２）中、Ｙはアルキレンイミン構造単位又はＮ−アシルアルキレンイミン構造単位の少なくとも一種からなる数平均重合度が５〜２０００の範囲にある直鎖状ポリマー鎖を有する側鎖を表し、複数あるＹは同一でも異なっていてもよく、ｎ_１は１〜３の整数である。）
で表される構造単位（ａ２）、
式（３）

(In Formula (2), Y represents a side chain having a linear polymer chain having a number average degree of polymerization in the range of 5 to 2000 consisting of at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit; A plurality of Y may be the same or different, and n ₁ is an integer of ₁ to 3.)
A structural unit (a2) represented by
Formula (3)

（式（３）中、Ｙはアルキレンイミン構造単位又はＮ−アシルアルキレンイミン構造単位の少なくとも一種からなる数平均重合度が５〜２０００の範囲にある直鎖状ポリマー鎖を有する側鎖を表し、複数あるＹは同一でも異なっていてもよく、ｎ_２は１〜３の整数である。）
で表される構造単位（ａ３）、
式（４）

(In Formula (3), Y represents a side chain having a linear polymer chain having a number average degree of polymerization in the range of 5 to 2000 consisting of at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit; A plurality of Y may be the same or different, and n ₂ is an integer of 1 to _3. )
A structural unit (a3) represented by:
Formula (4)

（式（４）中、Ｚはフェニル基又はビフェニル基を表し、Ｙはアルキレンイミン構造単位又はＮ−アシルアルキレンイミン構造単位の少なくとも一種からなる数平均重合度が５〜２０００の範囲にある直鎖状ポリマー鎖を有する側鎖を表し、Ｒ_１は炭素数１〜５のアルキル基を表し、複数あるＹは同一でも異なっていてもよく、ｍ_１は１〜３の整数である。）
で表される構造単位（ａ４）からなる群から選ばれる少なくとも一種の構造単位と、
一価の芳香族ヒドロキシ化合物残基（ｂ１）及び二価の芳香族ヒドロキシ化合物残基（ｂ２）からなる群から選ばれる少なくとも一種とからなる共重合体を好ましく使用できる。

(In the formula (4), Z represents a phenyl group or a biphenyl group, and Y represents a linear chain having a number average degree of polymerization of at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit in the range of 5 to 2000. R ₁ represents a C 1-5 alkyl group, a plurality of Ys may be the same or different, and m ₁ is an integer of ₁ to 3).
At least one structural unit selected from the group consisting of structural units (a4) represented by:
A copolymer comprising at least one selected from the group consisting of a monovalent aromatic hydroxy compound residue (b1) and a divalent aromatic hydroxy compound residue (b2) can be preferably used.

  The linear polymer chain that the copolymer of the present invention has in the side chain, that is, the linear polymer chain Y in the structure represented by the above formulas (1) to (4) is an alkyleneimine structural unit or N-acyl. A linear polymer chain comprising at least one alkyleneimine structural unit. Among them, an ethyleneimine structural unit, a propyleneimine structural unit, an N-acylethyleneimine structural unit having an acyl group having 1 to 18 carbon atoms, and an N-acylpropyleneimine structural unit having an acyl group having 1 to 18 carbon atoms. What consists of the structural unit chosen from the group which consists of at least 1 type is preferable in order to show favorable pigment dispersibility.

  Examples of the linear polymer chain include a linear polymer chain consisting only of N-acylethyleneimine structural units, a linear polymer chain consisting only of ethyleneimine structural units, and a linear chain consisting only of N-acylpropyleneimine structural units. -Like polymer chain, linear polymer chain consisting only of propyleneimine structural units, and linear polymer chain consisting of N-acylethyleneimine or a combination of N-acylpropyleneimine structural units and ethyleneimine or propyleneimine structural units, and N Examples include a linear polymer chain composed of a combination of an acylethyleneimine structural unit and an N-acylpropyleneimine structural unit. A linear polymer chain using structural units having different acyl groups can also be used as the N-acylethyleneimine or N-acylpropyleneimine structural unit. The polymer chain consisting only of the N-acylethyleneimine or N-acylpropyleneimine structural unit is highly hydrophilic, and salts such as its hydrochloride are more water-soluble. Among these linear polymer chains, the linear polymer chain composed of two or more kinds of structural units may be a random polymer chain or a block polymer chain, and a block polymer chain is particularly preferable.

  Of the above linear polymer chains, a linear polymer chain composed of an N-acylethyleneimine structural unit and / or an N-acylpropyleneimine structural unit is a polyoxazoline generally obtained by cation living polymerization of an oxazoline monomer, Among them, examples of linear polymer chains composed of ethyleneimine structural units include poly (N-formylethyleneimine), poly (N-acetylethyleneimine), poly (N-propionylethyleneimine), poly (N- Butyrylethyleneimine), poly (N-isobutyrylethyleneimine), poly (N-pivaloylethyleneimine), poly (N-lauroylethyleneimine), poly (N-stearoylethyleneimine), poly (N- Fats such as (3- (perfluorooctyl) propionyl) ethyleneimine) Acylated with aliphatic unsaturated carboxylic acids such as polyethylenimine, poly (N-acryloylethyleneimine), poly (N-methacryloylethyleneimine), poly (N-oleoylethyneimine) acylated with aliphatic saturated carboxylic acid Aromatic carboxylic acids such as modified ethyleneimine, poly (N-benzoylethyleneimine), poly (N-toluoylethyleneimine), poly (N-naphthoylethyleneimine), poly (N-cinnamoylethyleneimine), etc. And polyethyleneimine acylated with.

  Examples of linear polymer chains composed of propyleneimine structural units include, for example, poly (N-formylpropyleneimine), poly (N-acetylpropyleneimine), poly (N-propionylpropyleneimine), poly (N -Butyrylpropylimine), poly (N-isobutyrylpropyleneimine), poly (N-pivaloylpropyleneimine), poly (N-lauroylpropyleneimine), poly (N-stearoylpropyleneimine), poly (N -(3- (perfluorooctyl) propionyl) propyleneimine) and other aliphatic saturated carboxylic acid acylated polypropyleneimine, poly (N-acryloylpropyleneimine), poly (N-methacryloylpropyleneimine), poly (N -Oleoyl ethinimine) etc. Propyleneimine acylated with carboxylic acid, poly (N-benzoylpropyleneimine), poly (N-toluoylpropyleneimine), poly (N-naphthoylpropyleneimine), poly (N-cinnamoylpropyleneimine), etc. And polypropyleneimine acylated with the above aromatic carboxylic acid.

  As the structural formulas of the polymer chains exemplified above, those represented by the formulas (5) to (8) are particularly preferable examples.

（式（５）中、ｐ_１は２又は３であり、ｑ_１は５〜２０００の範囲である。）

(In formula (5), p ₁ is 2 or 3, and q ₁ is in the range of ₅ to 2000.)

（式（６）中、Ａ_１は炭素数が１〜１８のアシル基を表し、ｐ_２は２又は３であり、ｑ_２は５〜２０００の範囲である。）

(In the formula (6), _{A 1} represents an acyl group having 1 to 18 carbon atoms, _{p 2} is 2 or 3, _{q 2} is in the range of 5 to 2,000.)

（式（７）中、Ａ_２は炭素数が１〜１８のアシル基を表し、ｐ_３及びｐ_４は２又は３であり、ｑ_３＋ｑ_４は５〜２０００の範囲である。）
又は、式（８）

(In the formula (7), _{A 2} represents an acyl group having 1 to 18 carbon atoms, _{p 3} and _{p 4} is 2 or _{3, q} 3 + q ₄ is in the range of 5 to 2,000.)
Or formula (8)

（式（８）中、Ａ_３、Ａ_４は炭素数が１〜１８のアシル基を表し、各々異なるものであり、ｐ_５及びｐ_６は２又は３であり、ｑ_５＋ｑ_６は５〜２０００の範囲である。）
から選ばれる一種である直鎖状ポリマー鎖は、構造制御が容易であるため好ましい。

(In the formula _{(8), A 3, A} 4 represents an acyl group having 1 to 18 carbon atoms, and in each different, _{p 5} and _{p 6} is 2 or _{3, q} 5 + q ₆ is 5 (The range is 2000.)
A linear polymer chain which is a kind selected from is preferable because the structure can be easily controlled.

  In addition, as a xanthene residue which may have an alkyl group having 1 to 5 carbon atoms as a substituent selected as X of the alkyleneimine copolymer of the present invention represented by the above formula (1), Examples thereof include divalent groups having a xanthene skeleton represented by formula (9) and formula (10), and these can be suitably used because of their high heat resistance and solubility.

（式（９）及び式（１０）中、Ｂ_１及びＢ_２は炭素原子、メチレン基、炭素原子数１〜４のアルキル基で置換されたメチレン基、フェニル基で置換されたメチレン基、ナフチル基で置換されたメチレン基、ビフェニル基で置換されたメチレン基、９−フルオレニル基で置換されたメチレン基、又は該フェニル基、該ナフチル基、若しくは該ビフェニル基上に更にアルキル基が芳香核置換したメチレン基を表し、Ｒ_２〜Ｒ_７は炭素数１〜５のアルキル基を表し、ｍ_２、ｍ_３及びｍ_６、ｍ_７は各々独立して０〜３の整数を表し、ｍ_４及びｍ_５は各々独立して０〜２の整数を表す。）

(In Formula (9) and Formula (10), B ₁ and B ₂ are carbon atoms, methylene groups, methylene groups substituted with alkyl groups having 1 to 4 carbon atoms, methylene groups substituted with phenyl groups, naphthyl. A methylene group substituted with a group, a methylene group substituted with a biphenyl group, a methylene group substituted with a 9-fluorenyl group, or an alkyl group further substituted with an aromatic nucleus on the phenyl group, the naphthyl group, or the biphenyl group It represents methylene _group, R 2 to R ₇ represents an alkyl group having 1 to 5 carbon _{atoms, m 2,} m ₃ and _m 6, _{m 7} each independently represents an integer of 0 to 3, _{m 4} and m ₅ each independently represents an integer of 0 to 2.)

  As a biphenylene residue which may have a C1-C5 alkyl group as a substituent selected as X in the said Formula (1), for example, the bivalent represented by Formula (11) Group, which can be suitably used because of its high heat resistance.

（式（１１）中、Ｒ_８及びＲ_９は、炭素数１〜５のアルキル基を表し、ｍ_８及びｍ_９は各々独立して０〜４の整数を表す。）

(In Formula (11), R ₈ and R ₉ represent an alkyl group having 1 to 5 carbon atoms, and m ₈ and m ₉ each independently represent an integer of 0 to 4)

  Examples of the bisphenyl residue optionally having an alkyl group having 1 to 5 carbon atoms or a halogen atom selected as X in the above formula (1) are represented by the formula (12). The divalent group can be preferably used because of its high solubility.

（式（１２）中、Ｂ_３は−Ｃ（ＣＨ_３）_２−、−ＣＨ（ＣＨ_３）−、−ＣＨ_２−、−Ｃ（ＣＨ_３）（ＣＨ_２ＣＨ_３）−、−Ｃ（ＣＨ_３）（Ｃ_６Ｈ_５）−または−ＳＯ_２−を表し、Ｒ_１０及びＲ_１１は炭素数１〜５のアルキル基又はハロゲン原子を表し、ｍ_１０及びｍ_１１は各々独立して０〜４の整数を表す。）

(In Formula (12), B ₃ represents —C (CH ₃ ) ₂ —, —CH (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) (CH ₂ CH ₃ ) —, —C (CH ₃ ) represents (C ₆ H ₅ ) — or —SO ₂ —, R ₁₀ and R ₁₁ represent an alkyl group having 1 to 5 carbon atoms or a halogen atom, and m ₁₀ and m ₁₁ each independently represent 0 to 4 Represents an integer.)

  The monovalent aromatic hydroxy compound residue (b1) in the present invention is not particularly limited as long as it is a residue of a monovalent aromatic hydroxy compound that reacts with a glycidyl compound. For example, a biphenyl alcohol residue, a diphenyl alcohol residue Group, phenol residue, naphthol residue, anthranol residue, hydroxypyrene residue, hydroxyanthraquinone residue, hydroxybenzimidazole residue, hydroxybenzothiazole residue, hydroxycarbazole residue, hydroxydibenzofuran residue, Examples thereof include monovalent aromatic hydroxy compound residues such as hydroxyindole residues, hydroxyquinoline residues, hydroxyacridine residues, and hydroxyquinoxaline residues.

  The monovalent aromatic hydroxy compound residue is an alkylamino having 1 to 5 carbon atoms, an nitro group, a cyano group, a phenyl group, a sulfonic acid group, an amino group, or an alkylamino group having 1 to 5 carbon atoms. And a substituent such as a dialkylamino group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms.

  Among them, when giving a rigid skeleton to the obtained copolymer, aromatic hydroxy compounds having a biphenyl skeleton such as 4-phenylphenol and 4-hydroxy-4-biphenylcarbonitrile, bisphenol A-type hydroxy compounds, bisphenol F Type hydroxy compounds, bisphenol S type hydroxy compounds, aromatic hydroxy compounds having a diphenyl skeleton such as bisphenol hydroxy compounds, phenol compounds, naphthol compounds, anthranol compounds, hydroxypyrene compounds, hydroxyanthraquinone compounds, hydroxybenzimidazol compounds, hydroxybenzos Thiazole compounds, hydroxycarbazole compounds, hydroxydibenzofuran compounds, hydroxyindole compounds, hydroxyquinoline compounds, hydroxyactol compounds Jin compound is preferably a residue such as dyes having an aromatic alcohol structure monohydric such as hydroxy quinoxaline compound.

  Among the monovalent aromatic hydroxy compound residues having a biphenyl skeleton, the monovalent aromatic hydroxy compound residue represented by the formula (13) is preferable because the heat resistance of the resulting copolymer can be improved. .

（式（１３）中、Ｒ_１２及びＲ_１３は炭素数が１〜５のアルキル基、ニトロ基、シアノ基、フェニル基、スルホン酸基、アミノ基、アルキル基の炭素数が１〜５のアルキルアミノ基、アルキル基の炭素数が１〜５のジアルキルアミノ基、炭素数が１〜５のアルコキシ基、炭素数が１〜５のアルデヒド基のいずれかを表し、ｍ_１２は１〜４、ｍ_１３は１〜５の整数である。）

(In the formula (13), R ₁₂ and R ₁₃ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. It represents any of an amino group, a dialkylamino group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an aldehyde group having 1 to 5 carbon atoms, m ₁₂ is 1 to 4, m ₁₃ is an integer of 1 to 5.)

  Among the monovalent aromatic hydroxy compound residues having a diphenyl skeleton, the monovalent aromatic hydroxy compound residue represented by the formula (14) has the solubility of the aromatic hydroxy compound that gives the structure. Since it is high, preparation is easy and preferable.

（式（１４）中、Ｒ_１４及びＲ_１５は炭素数が１〜５のアルキル基、ニトロ基、シアノ基、フェニル基、スルホン酸基、アミノ基、アルキル基の炭素数が１〜５のアルキルアミノ基、アルキル基の炭素数が１〜５のジアルキルアミノ基、炭素数が１〜５のアルコキシ基、又は炭素数が１〜５のアルデヒド基のいずれかを表し、Ｄ_１は−Ｓ−、−Ｏ−、−ＣＯ−、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−、−ＳＯ_２−、−Ｎ＝Ｎ−、−ＣＨ＝ＣＨ−、−Ｃ（Ｃ_６Ｈ_１１）−、又は−ＣＯＯＣＨ_２−で表されるいずれかの構造であり、ｍ_１４は１〜４、ｍ_１５は１〜５の整数である。）

(In the formula (14), R ₁₄ and R ₁₅ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. amino group, a dialkylamino group having 1 to 5 carbon atoms in the alkyl group, or an aldehyde group of an alkoxy group having 1 to 5 carbon atoms, or carbon atoms to 5, D ₁ is -S-, _{-O -, - CO -, -} CH 2 -, - C (CH 3) 2 -, - SO 2 -, - N = N -, - CH = CH -, - C (C 6 H 11) -, or (It is any structure represented by —COOCH ₂ —, m ₁₄ is an integer of 1 to 4, and m ₁₅ is an integer of 1 to 5.)

  In addition, among monovalent aromatic hydroxy compound residues which are residues of pigments having an aromatic alcohol structure, phenol compounds, naphthol compounds, anthranol compounds, hydroxypyrene compounds, hydroxyanthraquinone compounds, hydroxybenzimidazo Residues such as benzene compounds, hydroxybenzothiazole compounds, hydroxycarbazole compounds, hydroxydibenzofuran compounds, hydroxyindole compounds, hydroxyquinoline compounds, hydroxyacridine compounds, hydroxyquinoxaline compounds are preferred because they have good interaction with the dye compounds. .

  The divalent aromatic hydroxy compound residue (b2) is not particularly limited as long as it is a divalent aromatic hydroxy compound residue that reacts with a glycidyl compound. For example, a biphenol residue, a diphenyldihydroxy residue , Dihydroxybenzene residue, dihydroxynaphthalene residue, dihydroxyanthracene residue, dihydroxypyrene residue, dihydroxyanthraquinone residue, dihydroxybenzimidazole residue, dihydroxybenzothiazole residue, dihydroxycarbazole residue, dihydroxydibenzofuran residue Examples thereof include divalent aromatic hydroxy compound residues such as dihydroxyindole residues, dihydroxyquinoline residues, dihydroxyacridine residues, and dihydroxyquinoxaline residues.

  The divalent aromatic hydroxy compound residue is an alkylamino having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, a nitro group, a cyano group, a phenyl group, a sulfonic acid group, an amino group, or an alkyl group having 1 to 5 carbon atoms. And a substituent such as a dialkylamino group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms.

  Among them, when giving a rigid skeleton to the obtained copolymer, aromatic dihydroxy compounds having a biphenyl skeleton such as biphenol and dihydroxybiphenylcarbonitrile, bisphenol A type dihydroxy compounds, bisphenol F type dihydroxy compounds, bisphenol S type Aromatic dihydroxy compounds having a diphenyl skeleton such as dihydroxy compounds and bisphenol dihydroxy compounds, dihydroxybenzene compounds, dihydroxynaphthalene compounds, dihydroxyanthracene compounds, dihydroxypyrene compounds, dihydroxyanthraquinone compounds, dihydroxybenzimidazol compounds, dihydroxybenzothiazole compounds, dihydroxy Carbazole compounds, dihydroxydibenzofuran compounds, dihydroxyindole compounds Dihydroxy quinoline compounds, dihydroxy acridine compound, is preferably a residue such as dyes having a divalent aromatic alcohol structure such as dihydroxy quinoxaline compound.

  As the divalent aromatic hydroxy compound residue represented by the above divalent aromatic hydroxy compound residue (b2), the divalent represented by the formula (15) having the biphenyl skeleton or the formula (16) The aromatic hydroxy compound residues are preferred.

（式（１５）中及びＲ_１６及びＲ_１７は炭素数が１〜５のアルキル基、ニトロ基、シアノ基、フェニル基、スルホン酸基、アミノ基、アルキル基の炭素数が１〜５のアルキルアミノ基、アルキル基の炭素数が１〜５のジアルキルアミノ基、炭素数が１〜５のアルコキシ基、又は炭素数が１〜５のアルデヒド基のいずれかを表し、ｍ_１６及びｍ_１７は１〜４の整数である。）

(In the formula (15) and R ₁₆ and R ₁₇ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. An amino group, a dialkylamino group having 1 to 5 carbon atoms in an alkyl group, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms, and m ₁₆ and m ₁₇ are 1 It is an integer of ~ 4.)

（式（１６）中、Ｒ_１８及びＲ_１９は炭素数が１〜５のアルキル基、ニトロ基、シアノ基、フェニル基、スルホン酸基、アミノ基、アルキル基の炭素数が１〜５のアルキルアミノ基、アルキル基の炭素数が１〜５のジアルキルアミノ基、炭素数が１〜５のアルコキシ基、又は炭素数が１〜５のアルデヒド基のいずれかを表し、Ｄ_２は−Ｓ−、−Ｏ−、−ＣＯ−、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−、−ＳＯ_２−、−Ｎ＝Ｎ−、−ＣＨ＝ＣＨ−、−Ｃ（Ｃ_６Ｈ_１１）−、又は−ＣＯＯＣＨ_２−で表されるいずれかの構造であり、ｍ_１８及びｍ_１９は１〜４の整数である。）

(In the formula (16), R ₁₈ and R ₁₉ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. amino group, a dialkylamino group having 1 to 5 carbon atoms in the alkyl group, or an aldehyde group of an alkoxy group having 1 to 5 carbon atoms, or carbon atoms 1-5, D ₂ is -S-, _{-O -, - CO -, -} CH 2 -, - C (CH 3) 2 -, - SO 2 -, - N = N -, - CH = CH -, - C (C 6 H 11) -, or -COOCH ₂ - is any structure represented _{by, m 18} and _{m 19} is an integer of 1 to 4).

  In the copolymer of the present invention, the molar ratio (b1) / (b2) of the monovalent aromatic hydroxy compound residue (b1) to the divalent aromatic hydroxy compound residue (b2) is 3.3. In the range of ˜30, good pigment dispersibility is exhibited, and the range of 2-9 is more preferred.

  The average molecular weight of the copolymer polymer of the present invention is preferably in the range of 2500 to 1000000, and the effects of the present invention can be suitably achieved, and those in the range of 5000 to 500000 can be particularly preferably used.

  The pigment dispersant comprising a copolymer having the epoxy resin skeleton of the present invention as a main chain and a linear polymer chain having an alkyleneimine structural unit or an N-acylalkyleneimine structural unit as a side chain is hydrophobic in the main chain. It is considered that the polymer micelle of nanoparticles is formed in water, a hydrophilic solvent, or a hydrophobic solvent because of having a hydrophilic alkyleneimine structural unit in the side chain. Depending on the dispersion power and penetrating power of the pigment dispersing agent of the nanoparticle, the polymer of the nanoparticle is passed through a spontaneous pulverization process from a large primary particle of the pigment to a secondary particle of several tens of nanometers. It exhibits a characteristic function capable of forming micelles and maintaining a stable dispersed state. The size of the polymer micelle of the nanoparticle can be controlled by adjusting the molecular weight ratio between the main chain structure and the side chain structure and the pigment using the structure.

  Such a pigment dispersant made of the copolymer of the present invention does not require many other additives, and can form a good dispersion state without the need for an advanced mechanical grinding step.

  A copolymer having a main chain of an epoxy resin skeleton used in the present invention and a side chain of a linear polymer chain having an alkyleneimine structural unit or an N-acylalkyleneimine structural unit is composed of a polyfunctional glycidyl compound, A modified epoxy compound in which the side chain hydroxy group of an epoxy resin having a secondary alcohol structure obtained by reaction with a valent and divalent aromatic hydroxy compound is modified to a sulfonate group by a sulfonylating agent, which is a cationic polymerization initiator Can be obtained by a simple method of cationic polymerization of a cationically polymerizable monomer such as oxazoline.

  As the polyfunctional glycidyl compound that gives an epoxy resin having a secondary alcohol structure, any compound that reacts with an aromatic dihydroxy compound to give a hydroxy group to the side chain may be used.

  As such a polyfunctional glycidyl compound, diglycidyl compounds usually used for the synthesis of epoxy resins such as aromatic glycidyl compounds, alicyclic glycidyl compounds, and aliphatic glycidyl compounds can be used. Of these, the polyfunctional glycidyl compounds represented by the formulas (i) to (iv) are preferable because they provide a pigment dispersant having good pigment dispersibility.

（式（１）中、Ｘはキサンテン骨格を有する二価のフェノール残基、ビフェニレン残基、ビスフェノール残基から選ばれる二価の基を表す。）

(In formula (1), X represents a divalent group selected from a divalent phenol residue having a xanthene skeleton, a biphenylene residue, and a bisphenol residue.)

（式（ii）中、ｎ_１は１〜３の整数を表す。）

(In formula (ii), n ₁ represents an integer of ₁ to 3)

（式（iii）中、ｎ_２は１〜３の整数を表す。）

(In the formula (iii), _{n 2} represents an integer of 1-3.)

（式（iv）中、Ｚはフェニル基又はビフェニル基を表し、Ｒ_１は炭素数１〜５のアルキル基を表し、ｍ_１は１〜３の整数である。）

(In formula (iv), Z represents a phenyl group or a biphenyl group, R ₁ represents an alkyl group having 1 to 5 carbon atoms, and m ₁ is an integer of ₁ to 3).

  X in the above formula (i) is preferably a divalent group represented by the above formulas (9) to (12).

  The monovalent aromatic hydroxy compound to be reacted with these polyfunctional glycidyl compounds may be any one that provides the above-mentioned aromatic hydroxy compound residue. For example, optionally substituted biphenyl alcohol, diphenyl alcohol, phenol, naphthol, anthranol, hydroxypyrene, hydroxyanthraquinone, hydroxybenzimidazole, hydroxybenzothiazole, hydroxycabazol, hydroxydibenzofuran, hydroxyindole Aromatic hydroxy compounds exemplified above, such as hydroxyquinoline, hydroxyacridine, and hydroxyquinoxaline can be used.

  Of these, aromatic hydroxy compounds represented by the following formula (v) or (vi) can be preferably used.

(In the formula (v), R ₁₂ and R ₁₃ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. An amino group, a dialkylamino group having 1 to 5 carbon atoms in an alkyl group, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms, m ₁₂ is 1 to 4, m ₁₃ is an integer of 1-5.)

(In the formula (vi), R ₁₄ and R ₁₅ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. amino group, a dialkylamino group having 1 to 5 carbon atoms in the alkyl group, or an aldehyde group of an alkoxy group having 1 to 5 carbon atoms, or carbon atoms to 5, D ₁ is -S-, _{-O -, - CO -, -} CH 2 -, - C (CH 3) 2 -, - SO 2 -, - N = N -, - CH = CH -, - C (C 6 H 11) -, or (It is any structure represented by —COOCH ₂ —, m ₁₄ is an integer of 1 to 4, and m ₁₅ is an integer of 1 to 5.)

  Moreover, as a bivalent aromatic hydroxy compound made to react with said polyfunctional glycidyl compound, the aromatic hydroxy compounds illustrated above, such as biphenyl alcohol and diphenyl alcohol which may have a substituent, can be used.

  Of these, aromatic hydroxy compounds represented by the following formula (vii) or (viii) can be preferably used.

（式（vii）中、Ｒ_１６及びＲ_１７は炭素数が１〜５のアルキル基、ニトロ基、シアノ基、フェニル基、スルホン酸基、アミノ基、アルキル基の炭素数が１〜５のアルキルアミノ基、アルキル基の炭素数が１〜５のジアルキルアミノ基、炭素数が１〜５のアルコキシ基、又は炭素数が１〜５のアルデヒド基のいずれかを表し、ｍ_１６、ｍ_１７は１〜４の整数である。）

(In the formula (vii), R ₁₆ and R ₁₇ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. An amino group, an alkyl group, a dialkylamino group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms, m ₁₆ and m ₁₇ are 1 It is an integer of ~ 4.)

（式（viii）中、Ｒ_１８及びＲ_１９は炭素数が１〜５のアルキル基、ニトロ基、シアノ基、フェニル基、スルホン酸基、アミノ基、アルキル基の炭素数が１〜５のアルキルアミノ基、アルキル基の炭素数が１〜５のジアルキルアミノ基、炭素数が１〜５のアルコキシ基、又は炭素数が１〜５のアルデヒド基のいずれかを表し、Ｄは−Ｓ−、−Ｏ−、−ＣＯ−、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−、−ＳＯ_２−、−Ｎ＝Ｎ−、−ＣＨ＝ＣＨ−、−Ｃ（Ｃ_６Ｈ_１１）−、又は−ＣＯＯＣＨ_２−で表されるいずれかの構造であり、ｍ_１８、ｍ_１９は１〜４の整数である。）

(In Formula (viii), R ₁₈ and R ₁₉ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. An amino group, a dialkylamino group having 1 to 5 carbon atoms in an alkyl group, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms, D is -S-,- _{O -, - CO -, -} CH 2 -, - C (CH 3) 2 -, - SO 2 -, - N = N -, - CH = CH -, - C (C 6 H 11) -, or - (It is any structure represented by COOCH ₂ —, and m ₁₈ and m ₁₉ are integers of 1 to 4.)

  Modification of the side chain hydroxy group of an epoxy compound having a secondary alcohol structure obtained by the reaction of the polyfunctional glycidyl compound with a monovalent aromatic hydroxy compound and a divalent aromatic hydroxy compound is generally an amine or alkaline inorganic compound. This is achieved by allowing a sulfonylating agent such as sulfonic acid halide or sulfonic acid anhydride to act in the presence of a salt.

  Examples of the sulfonic acid halide include methanesulfonic acid halide, benzenesulfonic acid chloride, p-toluenesulfone which may be substituted with halogen such as methanesulfonic acid chloride, trifluoromethanemethanesulfonic acid chloride, and trichloromethanesulfonic acid chloride. Benzene sulfonic acid chloride optionally substituted with alkyl group or nitro group such as acid chloride, 2-nitrobenzene sulfonic acid chloride, 2,4-dinitrobenzene sulfonic acid chloride, 1-naphthalene sulfonic acid chloride and 2-naphthalene sulfone And naphthalenesulfonic acid halides such as acid chlorides.

  Among the sulfonic acid chlorides, benzene sulfonic acid chloride optionally substituted with an alkyl group or nitro group, or methane sulfonic acid chloride optionally substituted with a halogen atom is a modified epoxy resin which is a cationic polymerization initiator Methanesulfonic acid chloride, trifluoromethanesulfonic acid chloride, trichloromethanesulfonic acid chloride, benzenesulfonic acid chloride, p-toluenesulfonic acid chloride, 2-nitrobenzenesulfonic acid chloride, 2,4-dinitrobenzenesulfone An acid chloride is preferable in terms of easy availability of raw materials. In particular, p-toluenesulfonic acid chloride is preferable because the modified epoxy resin that is a cationic polymerization initiator has high stability, and trifluoromethanesulfonic acid chloride is preferable because the resulting modified epoxy compound has high cationic polymerization initiating ability.

  Examples of the sulfonic acid anhydride include methanesulfonic acid anhydride which may be substituted with halogen such as methanesulfonic acid anhydride, trifluoromethanemethanesulfonic acid anhydride, trichloromethanesulfonic acid anhydride, and benzenesulfonic acid anhydride. Benzenesulfonic acid anhydride which may be substituted with an alkyl group or nitro group such as p-toluenesulfonic acid anhydride, 2-nitrobenzenesulfonic acid anhydride, 2,4-dinitrobenzenesulfonic acid anhydride, etc. It is done.

  Among the sulfonic acid anhydrides, a methanesulfonic acid anhydride which may be substituted with a halogen atom is preferable because unreacted sulfonic acid anhydride can be distilled off under reduced pressure after the sulfonylation reaction of a hydroxyl group. Sulfonic acid anhydride, trifluoromethanesulfonic acid anhydride, and trichloromethanesulfonic acid anhydride are preferable in terms of easy availability of raw materials. In particular, trifluoromethanesulfonic anhydride is preferable because the modified epoxy resin that is a cationic polymerization initiator has high cationic polymerization initiating ability.

  The substitution reaction with a sulfonate group by a sulfonic acid halide is generally performed in the presence of a base. Examples of the base include aromatic tertiary amines such as pyridine, 4-dimethylaminopyridine and N, N-dimethylaniline, triethylamine, N , N, N ′, N′-tetramethylethylenediamine, aliphatic tertiary amines such as 1,4-diazabicyclo [2,2,2] octane, and alkaline inorganic salts such as potassium carbonate and calcium hydroxide.

  The ratio of substituting the side chain hydroxy group of the secondary alcohol structure with a sulfonate group can be adjusted by the amount of the sulfonic acid halide added and the type of base. For example, when all hydroxy groups are converted into sulfonate groups, a large excess molar amount of sulfonic acid halide or sulfonic acid anhydride may be used with respect to the hydroxy groups in the epoxy resin having a secondary alcohol structure. .

  When the hydroxy group is partially substituted with a sulfonate group, an aromatic tertiary amine such as pyridine or 4-dimethylaminopyridine is used as a base, and a sulfonic acid halide is used in a small excess molar amount relative to the hydroxy group. The reaction temperature may be maintained at about room temperature.

  The copolymer used in the present invention uses a modified epoxy compound having a sulfonate group in the side chain obtained by the above method as a cationic polymerization initiator, and from the side chain sulfonate group of the modified epoxy compound, cationic polymerization such as oxazoline. It can be obtained by a simple method such as a method of cationic polymerization of a functional monomer or a method of hydrolyzing after cationic polymerization.

  Specific examples of the cationic polymerizable monomer include, for example, aziridine such as ethyleneimine, propyleneimine, N- (tetrahydropyranyl) ethyleneimine, N- (t-butyl) ethyleneimine, and alkyleneimine monomers such as azetidine, 2-alkyloxazolines such as 2-oxazoline, 2-methyloxazoline, 2-ethyloxazoline, 2-phenyloxazoline, 2-stearyloxazoline, 2- (3- (perfluorooctyl) propyl) oxazoline, 2-vinyloxazoline, Oxazoline monomers such as 2-alkenyl oxazolines such as 2-isopropenyl oxazoline and 2-oleyl oxazoline, 2-aryl oxazolines such as 2-phenyl oxazoline and ethylene oxazoline De, etc. oxirane monomers such as propylene oxide.

  In the production of the copolymer used in the present invention, the cationic polymerization conditions when the modified epoxy compound is used are alkyl sulfonate esters such as methyl p-toluenesulfonate and methyl trifluoromethanesulfonate and the cationic polymerization initiator. The conventional and known cationic polymerization conditions.

  In addition, a random polymer chain composed of a plurality of N-acylethyleneimine structural units can be formed by polymerization using a plurality of types of oxazoline monomers. Furthermore, since the cationic polymerization of oxazoline is generally a living polymerization, the type of oxazoline monomer is selected. A block polymer can be produced by a modified multi-stage polymerization. Thereby, the side chain of the copolymer used in the present invention can be a random polymer chain or a block polymer chain. For example, 2-phenyloxazoline is cationically polymerized with a cationic polymerization initiator of the modified epoxy resin, and then 2-methyloxazoline is polymerized to directly connect a poly (N-benzoylethyleneimine) chain to the epoxy resin. A copolymer having poly (N-acetylethyleneimine) directly linked to (N-benzoylethyleneimine) and having a block polymerized polyacylethyleneimine as a side chain can be obtained.

  Further, by partially hydrolyzing the polymer chain composed of the N-acylethyleneimine structural unit, a part of the N-acylethyleneimine structural unit in the polymer chain is hydrolyzed to become an ethyleneimine structural unit. -A copolymer having a random polymer chain composed of an acylethyleneimine structural unit and an ethyleneimine structural unit in the side chain can be obtained.

  When the polymer chain composed of the N-acylethyleneimine structural unit before hydrolysis is a block polymer, the N-acylimino group can be selectively hydrolyzed by controlling the hydrolysis conditions. The polyethyleneimine block and the poly (N -Diblock polymer comprising a polyethyleneimine block and an N-acylpolyethyleneimine block, such as a block copolymer chain with an -acetylethyleneimine) block or a block copolymer chain with a polyethyleneimine block and a poly (N-propionylethyleneimine) block A copolymer having a side chain can be synthesized.

  Producing a copolymer having a random copolymer side chain of an ethyleneimine structural unit and an N-acylethyleneimine structural unit even when the polymer chain composed of the N-acylethyleneimine structural unit before hydrolysis is a random polymer Can do.

  The copolymer used in the present invention has an ethyleneimine structure having an epoxy compound skeleton consisting of a polyfunctional glycidyl compound residue, a monovalent aromatic hydroxy compound residue and a divalent aromatic hydroxy compound residue as the main chain. A hydrophilic linear polymer chain having a unit such as an N-acylethyleneimine structural unit, a propyleneimine structural unit, an N-acylpropyleneimine structural unit, an ethylene glycol structural unit, and a propylene glycol structural unit as a side chain Therefore, the polymer micelle can be easily formed because the molecule has both a hydrophobic part and a hydrophilic part, and each structure can be controlled. For this reason, according to the pigment dispersant comprising the copolymer of the present invention, a functional compound that is originally insoluble or hardly soluble in water can be encapsulated and stably maintained in water. For example, a fluorescent aromatic hydrocarbon such as pyrene is encapsulated in a molecular state in the polymer micelle of the pigment dispersant of the present invention, and can exist stably in water.

  Thus, the copolymer used in the present invention is a modified epoxy compound in which a side chain hydroxy group in a modified epoxy having a secondary alcohol structure is substituted with a group having a high leaving ability such as an alkyl sulfonate group or an aryl sulfonate group. Can be produced by cationic polymerization of a cationic polymerizable monomer such as oxazoline or substitution of a polyalkylene glycol with the modified epoxy compound. Therefore, the pigment dispersant of the present invention is extremely It can be manufactured by a simple and easy method.

  Hereinafter, the present invention will be described in more detail with reference to examples. Unless otherwise specified, “%” represents “mass%”.

Example 1
Bisphenol A-type linear epoxy resin 9.3 g (“AM-040-P” manufactured by Dainippon Ink & Chemicals, Inc.) (10 m equivalent, epoxy equivalent 933 g), 4-phenylphenol 2.56 g (15. 0 mmol), 0.13 ml (0.06 mol%) of a 65% ethyl acetate triphenylphosphonium ethanol solution and 50 ml of N, N-dimethylacetamide were reacted at 120 ° C. for 6 hours under a nitrogen atmosphere. After allowing to cool, the solution was dropped into 150 ml of water, and the resulting precipitate was washed twice with methanol and then dried under reduced pressure at 60 ° C. to obtain a monofunctional epoxy compound. The yield of the product obtained was 10.3 g.

  As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the epoxy ring was opened by 100% from 4-phenylphenol.

30 ml of a chloroform solution containing 10.3 g of a modified bisphenol A-type linear epoxy resin having a secondary hydroxy group in the side chain obtained from the above reaction (side chain hydroxy group 34.5 mmol) was stirred under ice-cooling in a nitrogen atmosphere, 24.12 ml (300 mmol) of pyridine was added. 30 ml of a chloroform solution containing 28.5 g (150 mmol) of p-toluenesulfonic acid chloride was added dropwise with stirring under ice cooling in a nitrogen atmosphere, followed by stirring under ice cooling for 1 hour. Further, after reacting at 40 ° C. for 3 and a half hours, 200 ml of chloroform was added to the obtained pale yellow transparent liquid, and 21.5 ml (200 mmol of N, N-dimethylethylenediamine was added dropwise under ice-cooling and stirring. Was sufficiently stirred on ice and kept at a liquid temperature of 25 ° C. or lower, and 200 ml of a 10% hydrochloric acid aqueous solution was added to the resulting yellow liquid, followed by extraction with chloroform, and a 10% aqueous hydrochloric acid solution, a saturated aqueous sodium bicarbonate solution, After washing with water, it was dried over magnesium sulfate, suction filtered, and concentrated under reduced pressure to obtain 12.5 g of a pale yellow solid.
As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the modification rate of hydroxy group to p-toluenesulfonyl group was 100%.

  1.35 g (p-toluenesulfonyloxy group 3.0 mmol) of the modified epoxy resin obtained above, 5.1 g (60.0 mmol) of 2-methyloxazoline and 30 ml of N, N-dimethylacetamide under nitrogen atmosphere The mixture was stirred at 100 ° C. for 24 hours. 100 ml of ethyl acetate was added to the obtained yellow semi-solid and stirred vigorously at room temperature, followed by filtration, washing with ethyl acetate, and drying under reduced pressure to obtain 6.2 g of a white powdered solid. From the analysis by 1H-NMR, the obtained solid had a bisphenol A type epoxy resin as the main chain, the hydrogen at the o-position of the p-toluenesulfonyloxy group (δ 7.82 ppm), and poly (N-acetylethyleneimine). It was confirmed that the copolymer had a number average polymerization degree of 20 poly (N-acetylethyleneimine) as a side chain from an integral ratio of ethylene hydrogen (δ 3.47 ppm).

  The obtained copolymer was used as a pigment dispersant to disperse the pigment, and the dispersibility was observed. The pigments used were red (“Symuller Fast Red 4590”), yellow (“Symer Fast Yellow 4400T”), and blue (Fastogen Blue FGF) pigments manufactured by Dainippon Ink and Chemicals, Inc. 3 mg of the above pigment dispersant and 2 mg of each pigment were added to 5 ml of water, and then stirred at room temperature for 30 minutes.

  In any of the pigments, it was confirmed that the pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment had a spherical shape with a particle size of 50 to 70 nm, the red pigment had a particle size of 40 to 60 nm, and the yellow pigment had a spherical shape with a particle size of 80 to 100 nm.

(Example 2)
3.1 g of the copolymer obtained in Example 1 was stirred at 90 ° C. for 8 hours in 12.2 g of 5N hydrochloric acid water. After allowing to cool, about 50 ml of acetone was added to a solution containing a white precipitate that had formed over time. After standing, the supernatant was removed by decantation, and acetone addition, standing, and decantation were repeated. The acetone addition, standing, and decantation operations were further repeated twice, and then the white precipitate was filtered, washed with acetone, and then dried under reduced pressure at room temperature to obtain 2.8 g of a white powder solid. From the analysis by 1H-NMR, it was confirmed that the obtained solid was a copolymer having a bisphenol A type epoxy resin as a main chain and a polyethyleneimine hydrochloride having a number average polymerization degree of 20 as a side chain.

  Using the obtained copolymer as a pigment dispersant, a blue pigment was dispersed in the same manner as in Example 1 to observe the dispersibility. It was confirmed that the blue pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment was spherical with a particle size of 50 to 70 nm.

(Example 3)
3.1 g of 2,7-diglycidyloxy-1,3,4,5,6,8-hexamethyl-9-phenylxanthene (“EXA7335” manufactured by Dainippon Ink and Chemicals, 6.4 mmol), 4 , 4′-diglycidyloxybiphenyl 0.47 g (1.6 mmol), 4,4′-dihydroxybiphenyl 1.34 g (7.2 mmol), and ethyl triphenylphosphonium acetate in 70% methanol solution 0.021 g (0 .04 mmol) was heated and stirred at 140 ° C. in a nitrogen atmosphere in 5.0 g of N, N-dimethylacetamide and reacted for 4 hours. After allowing to cool, the pale yellow transparent semi-solid reaction solution was diluted with 20 g of N, N-dimethylacetamide and added dropwise to ice. The precipitated white block precipitate was filtered by suction and washed with ice water, and the block precipitate was boiled in 300 ml of water for 30 minutes with vigorous stirring. After cooling, the precipitate obtained by decantation was pulverized, and the powdered precipitate was washed with water and methanol, and then dried under reduced pressure at 60 ° C. to obtain 4.6 g of xanthene-biphenylene copolymer type linear epoxy resin. Obtained.
As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the epoxy ring was opened by 100% from 4-phenylphenol.

15 ml of a chloroform solution containing 4.6 g of a modified epoxy resin having a secondary hydroxy group in the side chain obtained from the above reaction was stirred under ice-cooling in a nitrogen atmosphere, and 8.04 ml (100 mmol) of pyridine was added. 15 ml of a chloroform solution containing 9.5 g (50 mmol) of p-toluenesulfonic acid chloride was added dropwise with stirring under ice cooling in a nitrogen atmosphere, followed by stirring under ice cooling for 1 hour. After further reaction at 40 ° C. for 3 hours and a half, 100 ml of chloroform was added to the obtained pale yellow transparent liquid, and 7.2 ml (67 mmol) of N, N-dimethylethylenediamine was added dropwise with stirring under ice cooling. The mixture was kept under ice-cooling and kept at a liquid temperature of 25 ° C. or lower, and 100 ml of 10% hydrochloric acid aqueous solution was added to the resulting yellow liquid, followed by extraction with chloroform, and 10% hydrochloric acid aqueous solution, saturated aqueous sodium hydrogen carbonate solution, After washing with water, it was dried over magnesium sulfate, suction filtered, and concentrated under reduced pressure to obtain 5.9 g of a pale yellow solid.
As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the modification rate of the side chain hydroxy group to the p-toluenesulfonyl group was 100%.

  Using the modified epoxy resin obtained above 2.50 g (p-toluenesulfonoxy group 3.0 mmol), 2-methyloxazoline 5.1 g (60.0 mmol) and N, N-dimethylacetamide 30 ml In the same manner as in Example 2, 7.5 g of a pale yellow powdered solid was obtained. From the analysis by 1H-NMR in the same manner as in Example 2, the obtained solid had a xanthene-biphenylene copolymerization type epoxy resin as a main chain and a poly (N-acetylethyleneimine) having a number average polymerization degree of 20 on the side. It was confirmed that the copolymer was a chain.

  The copolymer epoxy resin 3.7g obtained above was stirred at 90 ° C. for 8 hours in 12.5 g of 5N hydrochloric acid water. After allowing to cool, about 60 ml of acetone was added to a solution containing a white precipitate that had formed over time. After standing, the supernatant was removed by decantation, and acetone addition, standing, and decantation were repeated. After this acetone addition, standing, and decantation operations were further repeated twice, the white precipitate was filtered, washed with acetone, and then dried under reduced pressure at room temperature to obtain 3.5 g of a white powder solid. From the analysis by 1H-NMR, it was confirmed that the obtained solid was a copolymer having xanthene-biphenylene copolymerization type epoxy resin as a main chain and polyethyleneimine hydrochloride having a number average polymerization degree of 20 as a side chain. It was done.

  Using the obtained copolymer as a pigment dispersant, a blue pigment was dispersed in the same manner as in Example 1 to observe the dispersibility. It was confirmed that the blue pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment was spherical with a particle size of 70-90 nm.

Example 4
9.8 g (50 m equivalent, epoxy equivalent 196 g), 4-phenylphenol 11.9 g (70 mmol), 65% ethyl acetate, product name Epicoat 1031S [tetrakis (glycidyloxyallyl) ethane] of Japanepoxyresin (JER) 0.21 ml (0.1 mol%) of triphenylphosphonium ethanol solution and 40 ml of N, N-dimethylacetamide were reacted at 160 ° C. for 4 hours under a nitrogen atmosphere. After allowing to cool, the solution was dropped into 100 ml of water, and the resulting precipitate was washed twice with methanol and then dried under reduced pressure at 70 ° C. to obtain 17.6 g of a modified epoxy compound having a hydroxy group in a biphenylene side chain. Obtained.

As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the epoxy ring was opened by 100% from 4-phenylphenol.

  In a solution of 9.15 g (25.0 m equivalent) of a biphenylene type modified epoxy compound having an alcoholic hydroxy group in the side chain obtained above, 20.0 g (250 mmol) of pyridine and 30 ml of chloroform, p-toluenesulfonic acid chloride was added. A solution of chloroform (30 ml) containing 14.3 g (75 mmol) was added dropwise for 30 minutes with stirring under ice cooling in a nitrogen atmosphere. After completion of dropping, the mixture was further stirred at a bath temperature of 40 ° C. for 4 hours. After completion of the reaction, 60 ml of chloroform was added to dilute the reaction solution. Subsequently, after sequentially washing with 100 ml of 5% aqueous hydrochloric acid solution, saturated aqueous sodium hydrogen carbonate solution and saturated aqueous sodium chloride solution, it was dried over magnesium sulfate, filtered and concentrated under reduced pressure. The obtained solid was washed several times with methanol, filtered, and dried under reduced pressure at 70 ° C. to obtain 13.0 g of a modified epoxy compound.

  As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the modification rate of the side chain hydroxy group to the p-toluenesulfonyl group was 100%.

  2.08 g (4.0 m equivalent) of a modified epoxy compound having a p-toluenesulfonyloxy group in the side chain synthesized above, 6.8 g (80.0 mmol) of 2-methyloxazoline and 40 ml of N, N-dimethylacetamide were added. The mixture was stirred at 100 ° C. for 24 hours in a nitrogen atmosphere. After adding 300 ml of ethyl acetate to the resulting reaction mixture and stirring vigorously at room temperature, the product solid was filtered, washed twice with ethyl acetate, and dried under reduced pressure to obtain 8.7 g of a white powder solid. From the analysis by 1H-NMR, the obtained solid had a modified epoxy having a tetrakisphenylethane structure as a main chain (δ 6.45 to 7.90 ppm) and poly (N-acetylethyleneimine) as a side chain [ethylene hydrogen. (Δ 3.47 ppm), acetyl hydrogen (δ 2.00 ppm)], and a poly (N-acetylethyleneimine) copolymer having a number average degree of polymerization of 20 from quantitative calculation of reactants and products. It was confirmed.

  Dispersibility was observed by dispersing the pigment in the same manner as in Example 1 using the obtained copolymer as a pigment dispersant. In any of the pigments, it was confirmed that the pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment had a spherical shape with a particle size of 40 to 60 nm, the red pigment had a particle size of 20 to 40 nm, and the yellow pigment had a spherical shape with a particle size of 80 to 100 nm.

(Example 5)
3.8 g of the poly (N-acetylethyleneimine) copolymer obtained in Example 4 was stirred in 90 ° C. for 6 hours in 15.2 g of 5N aqueous hydrochloric acid to carry out a hydrolysis reaction. After standing to cool, the reaction mixture solution containing the white precipitate formed over time is added to about 150 ml of acetone and stirred at room temperature for about 30 minutes, and then the product solid is filtered, washed twice with acetone, and dried under reduced pressure. 3.3 g of a white solid was obtained. From the analysis by 1H-NMR, poly (N-acetylethyleneimine) is free from side chain acetylhydrogen (δ 2.00 ppm) by hydrolysis, and the obtained solid has polyethyleneimine hydrochloride as the side chain. It was confirmed to be a copolymer.

  Using the obtained copolymer as a pigment dispersant, a blue pigment was dispersed in the same manner as in Example 1 to observe the dispersibility. It was confirmed that the blue pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment was spherical with a particle size of 40 to 60 nm.

(Example 6)
Japan Epoxy Resin (JER) trade name Epicoat 1031S [tetrakis (glycidyloxyallyl) ethane] 9.8 g (50 m equivalent, epoxy equivalent 196 g), 4.4'-biphenol 5.95 g (35 mmol), 65% acetic acid An ethyltriphenylphosphonium ethanol solution (0.21 ml, 0.1 mol%) and N, N-dimethylacetamide (40 ml) were reacted at 130 ° C. for 2 hours in a nitrogen atmosphere. Thereafter, 2.79 g (15 mmol) of 4-phenylphenol was further added and the reaction was continued for 3 hours. After allowing to cool, the solution was dropped into 100 ml of water, and the resulting precipitate was washed twice with methanol and then dried under reduced pressure at 70 ° C. to obtain a modified epoxy polymer compound having a hydroxy group in the biphenylene side chain. .5 g was obtained. As a result of GPC measurement (HLC-8020, manufactured by Tosoh Corporation) of the obtained polymer epoxy, the molecular weight was 5,100.

As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the epoxy ring was opened by 100% from 4-phenylphenol.

  In a solution of 13.7 g of a biphenylene-type modified epoxy polymer compound having an alcoholic hydroxy group in the side chain obtained above, 30 g (375 mmol) of pyridine and 50 ml of chloroform, 21.5 g (113 mmol) of p-toluenesulfonic acid chloride was added. A chloroform (50 ml) solution containing was added dropwise for 30 minutes with stirring under ice cooling in a nitrogen atmosphere. After completion of dropping, the mixture was further stirred at a bath temperature of 40 ° C. for 4 hours. After completion of the reaction, 100 ml of chloroform was added to dilute the reaction solution. Subsequently, after sequentially washing with 150 ml of 5% hydrochloric acid aqueous solution, saturated aqueous sodium hydrogen carbonate solution and saturated aqueous sodium chloride solution, it was dried over magnesium sulfate, filtered and concentrated under reduced pressure. The obtained solid was washed several times with methanol, filtered, and dried under reduced pressure at 70 ° C. to obtain 19.5 g of a modified epoxy compound.

  As a result of 1H-NMR measurement (manufactured by JEOL Ltd., AL300, 300 MHz), the modification rate of the side chain hydroxy group to the p-toluenesulfonyl group was 100%.

  2.60 g (5 m equivalent) of a modified epoxy polymer compound having a p-toluenesulfonyloxy group in the side chain synthesized above, 8.50 g (100 mmol) of 2-methyloxazoline and 50 ml of N, N-dimethylacetamide were mixed with nitrogen. The mixture was stirred at 100 ° C. for 24 hours under an atmosphere. After adding 300 ml of ethyl acetate to the resulting reaction mixture and stirring vigorously at room temperature, the product solid was filtered, washed twice with ethyl acetate, and dried under reduced pressure to obtain 10.8 g of a white powder solid. The yield during polymerization was 99%. From the analysis by 1H-NMR, the obtained solid had an epoxy skeleton having a tetrakisphenylethane structure as a main chain (δ: 6.45 to 7.90 ppm) and poly (N-acetylethyleneimine) as a side chain [ethylene. Hydrogen (δ: 3.47 ppm), acetyl hydrogen (δ: 2.00 ppm)], and from this and quantitative calculation of the reaction product and the product, a poly ( N-acetylethyleneimine) as a side chain.

  Dispersibility was observed by dispersing the pigment in the same manner as in Example 1 using the obtained copolymer as a pigment dispersant. In any of the pigments, it was confirmed that the pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment had a spherical shape with a particle size of 60 to 80 nm, the red pigment had a particle size of 40 to 60 nm, and the yellow pigment had a spherical shape with a particle size of 90 to 110 nm.

(Example 7)
5.7 g of the poly (N-acetylethyleneimine) copolymer obtained in Synthesis Example 6 was stirred in 22.8 g of 5N aqueous hydrochloric acid at 90 ° C. for 6 hours to carry out a hydrolysis reaction. After allowing to cool, the reaction mixture solution containing white precipitate that has formed over time is added to about 200 ml of acetone and stirred at room temperature for about 30 minutes, and then the product solid is filtered, washed twice with acetone, and dried under reduced pressure. 4.9 g of a white solid was obtained. The yield was 99%. From the analysis by 1H-NMR, there was no side chain acetyl hydrogen (δ: 2.00 ppm) of poly (N-acetylethyleneimine) by hydrolysis reaction, and the obtained solid had polyethyleneimine hydrochloride as the side chain. It was recognized that it was a copolymer.

  Using the obtained copolymer as a pigment dispersant, a blue pigment was dispersed in the same manner as in Example 1 to observe the dispersibility. It was confirmed that the blue pigment showed a good dispersion state in water and formed stable spherical particles. As a result of observation with an electron microscope, the blue pigment was spherical with a particle size of 60 to 80 nm.

As described above, it was clear that the pigment dispersant of the present invention does not require many other additives and can form a good dispersion state without going through an advanced mechanical grinding process.

Claims (9)

A main chain having an epoxy resin skeleton, and a side chain having a linear polymer chain consisting of at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit and having a number average degree of polymerization in the range of 5 to 2,000. A copolymer having the formula (1)

[In the formula (1), X represents the formula (9)

Formula (10)

[In Formula (9) and Formula (10), B ₁ and B ₂ are carbon atoms, methylene groups, methylene groups substituted with alkyl groups having 1 to 4 carbon atoms, methylene groups substituted with phenyl groups, naphthyl. A methylene group substituted with a group, a methylene group substituted with a biphenyl group, a methylene group substituted with a 9-fluorenyl group, or an alkyl group further substituted with an aromatic nucleus on the phenyl group, the naphthyl group, or the biphenyl group It represents methylene _group, R 2 to R ₇ represents an alkyl group having 1 to 5 carbon _{atoms, m 2,} m ₃ and _m 6, _{m 7} each independently represents an integer of 0 to 3, _{m 4} and m ₅ each independently represents an integer of 0 to 2. ]
A xanthene residue represented by
Formula (11)

In [Equation (11), _{R 8} and _{R 9} represents an alkyl group having 1 to 5 carbon atoms, _{m 8} and _{m 9} each independently represent an integer of to 0-4. ]
A biphenol residue represented by
Formula (12)

Wherein (12), _{B 3} is _{-C (CH 3) 2 -,} - CH (CH 3) -, - CH 2 -, - C (CH 3) (CH 2 CH 3) -, - C (CH ₃ ) represents (C ₆ H ₅ ) — or —SO ₂ —, R ₁₀ and R ₁₁ represent an alkyl group having 1 to 5 carbon atoms or a halogen atom, and m ₁₀ and m ₁₁ each independently represent 0 to 4 Represents an integer. ]
And at least one divalent group selected from the group consisting of bisphenol residues represented by the formula: Y is a number average degree of polymerization consisting of at least one alkyleneimine structural unit or N-acylalkyleneimine structural unit of 5 to 5. It represents a side chain having a linear polymer chain in the range of 2000, and a plurality of Y may be the same or different. ]
A structural unit (a1) represented by:
Formula (2)

[In the formula (2), Y represents a side chain having a linear polymer chain having a number average degree of polymerization in the range of 5 to 2000 consisting of at least one of an alkyleneimine structural unit or an N-acylalkyleneimine structural unit; A plurality of Y may be the same or different, and n ₁ is an integer of ₁ to 3. ]
A structural unit (a2) represented by
Formula (3)

[In Formula (3), Y represents a side chain having a linear polymer chain having a number average degree of polymerization in the range of 5 to 2000 consisting of at least one alkyleneimine structural unit or N-acylalkyleneimine structural unit; plurality of Y may be the same or different, n ₂ is an integer of 1-3. ]
At least one structural unit selected from the group consisting of structural units (a3) represented by:
A pigment dispersant comprising a copolymer comprising at least one selected from the group consisting of a monovalent aromatic hydroxy compound residue (b1) and a divalent aromatic hydroxy compound residue (b2). The linear polymer chain has an ethyleneimine structural unit, a propyleneimine structural unit, an N-acylethyleneimine unit having an acyl group having 1 to 18 carbon atoms, and an N- having an acyl group having 1 to 18 carbon atoms. pigment dispersing agent according to claim 1 Symbol mounting is made of at least one acyl propyleneimine units. The linear polymer chain has the formula (5),

Wherein (5), _{p 1} is 2 or 3, _{q 1} is in the range of 5 to 2,000. ]
Formula (6),

Wherein (6), _{A 1} represents an acyl group having 1 to 18 carbon atoms, _{p 2} is 2 or 3, _{q 2} is in the range of 5 to 2,000. ]
Formula (7),

Wherein (7), _{A 2} represents an acyl group having 1 to 18 carbon atoms, _{p 3} and _{p 4} is 2 or _{3, q} 3 + q ₄ is in the range of 5 to 2,000. ]
And equation (8)

In [Equation _{(8), A 3, A} 4 represents an acyl group having 1 to 18 carbon atoms, and in each different, _{p 5} and _{p 6} is 2 or _{3, q} 5 + q ₆ is 5 The range is 2000. ]
The pigment dispersant according to claim 1 or 2 , wherein the pigment dispersant is selected from. The monovalent aromatic hydroxy compound residue (b1) may have a substituent such as biphenyl alcohol residue, diphenyl alcohol residue, phenol residue, naphthol residue, anthranol residue, hydroxypyrene residue. Group, hydroxyanthraquinone residue, hydroxybenzimidazole residue, hydroxybenzothiazole residue, hydroxycarbazole residue, hydroxydibenzofuran residue, hydroxyindole residue, hydroxyquinoline residue, hydroxyacridine residue, and hydroxy The pigment dispersant according to claim 1 , which is at least one selected from the group consisting of quinoxaline residues. The monovalent aromatic hydroxy compound residue (b1) has the formula (13)

[In the formula (13), R ₁₂ and R ₁₃ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. It represents any of an amino group, a dialkylamino group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and an aldehyde group having 1 to 5 carbon atoms, m ₁₂ is 1 to 4, m ₁₃ is an integer of 1-5. ]
And Equation (14)

[In the formula (14), R ₁₄ and R ₁₅ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, and alkyl groups having 1 to 5 carbon atoms. amino group, a dialkylamino group having 1 to 5 carbon atoms in the alkyl group, or an aldehyde group of an alkoxy group having 1 to 5 carbon atoms, or carbon atoms to 5, D ₁ is -S-, _{-O -, - CO -, -} CH 2 -, - C (CH 3) 2 -, - SO 2 -, - N = N -, - CH = CH -, - C (C 6 H 11) -, or -COOCH ₂ - is any structure represented _{by, m 14} is 1 to _{4, m 15} is an integer of 1 to 5. ]
The pigment dispersant according to any one of claims 1 to 4 , which is at least one selected from monovalent aromatic hydroxy compound residues represented by formula ( 1 ). The pigment according to any one of claims 1 to 5 , wherein the divalent aromatic hydroxy compound residue (b2) is at least one of a biphenyl alcohol residue and a diphenyl alcohol residue which may have a substituent. Dispersant. The divalent aromatic hydroxy compound residue (b2) is represented by the formula (15):

[In the formula (15), R ₁₆ and R ₁₇ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, alkyl groups having 1 to 5 carbon atoms. An amino group, a dialkylamino group having 1 to 5 carbon atoms in an alkyl group, an alkoxy group having 1 to 5 carbon atoms, or an aldehyde group having 1 to 5 carbon atoms, and m ₁₆ and m ₁₇ are 1 It is an integer of ~ 4. ]
And Equation (16)

[In the formula (16), R ₁₈ and R ₁₉ are alkyl groups having 1 to 5 carbon atoms, nitro groups, cyano groups, phenyl groups, sulfonic acid groups, amino groups, alkyl groups having 1 to 5 carbon atoms. amino group, a dialkylamino group having 1 to 5 carbon atoms in the alkyl group, or an aldehyde group of an alkoxy group having 1 to 5 carbon atoms, or carbon atoms 1-5, D ₂ is -S-, _{-O -, - CO -, -} CH 2 -, - C (CH 3) 2 -, - SO 2 -, - N = N -, - CH = CH -, - C (C 6 H 11) -, or -COOCH ₂ - is any structure represented _{by, m 18} and _{m 19} is an integer of 1 to 4. ]
The pigment dispersant according to any one of claims 1 to 6 , which is at least one selected from divalent aromatic hydroxy compound residues represented by: Claim molar ratio of aromatic hydroxy compound monovalent residues (b1) and divalent aromatic hydroxy compound residue (b2) (b1) / ( b2) is in the range of 3.3 to 30 1 The pigment dispersant in any one of -7 . The pigment dispersant according to any one of claims 1 to 8 , wherein the copolymer has an average molecular weight in the range of 2500 to 50000.