JP4069873B2 - Method for producing organic pigment dispersion - Google Patents

Description

The present invention relates to an organic pigment organic solvent dispersion excellent in dispersibility and storage stability.

  Organic pigments are used as colorants in a wide range of fields such as printing inks, paints, color filter paints, plastic forming materials, color filters, and ink jets. In general, it is important to finely disperse an organic pigment in an organic solvent in order to satisfy the required quality for these applications.

  Regarding the dispersion of the organic pigment, there is a method of dispersing using various additives, for example, a dispersant such as a surfactant or a pigment dispersion resin. However, dispersion with a surfactant is advantageous for dispersion in an aqueous system because it uses electrostatic repulsion between ionized polar functional groups to stabilize the dispersion, but in an organic solvent having a dielectric constant lower than that of water. In the dispersion in an organic solvent, a method using a pigment dispersion resin has been generally employed as disclosed in Patent Document 1 and Patent Document 2. In this method, the dispersion resin is adsorbed on the surface of the organic pigment particles, and the dispersion is stabilized by utilizing the steric repulsion between the adsorption resins. However, even in this case, if the interaction between the surface of the organic pigment and the dispersion resin is insufficient, the resin is desorbed and easily reaggregates. In addition, since general organic pigments have a small amount of surface functional groups that interact with the resin and many have a very small particle size and a large specific surface area, the amount of dispersed resin required for stabilization is large. Become. In addition, if the amount of the dispersed resin is increased, the amount of resin or additive that can be added to impart ink suitability or paint suitability is limited, or the compatibility between the dispersed resin and these additives is poor. In such a case, there is a problem that aggregation due to a thinning shock and stability with time of the ink and paint are lowered.

On the other hand, a method of carrying out dispersion using a pigment resin having an organic dye residue, an anthraquinone residue or a triazine residue as a base skeleton as a side chain and an acidic group or basic group as a substituent, and a dispersion resin, This is disclosed in Patent Document 3. As an action mechanism of this organic dye derivative, anthraquinone derivative or triazine derivative, various derivatives having polar functional groups and resins having polarities opposite to the functional groups possessed by various derivatives form salts by acid-base interactions. When dissolved in a solvent, this salt adsorbs the organic pigment residue, anthraquinone residue, or triazine residue on the surface of the organic pigment as an adsorption site, and the resin layer exhibits a steric repulsion effect, stabilizing the dispersion of the organic pigment. It is considered to be a plan. In this method, in most cases, an ink or a resin for coating can be used as a dispersion resin as it is, so that there is no compatibility problem caused by the dispersant and excellent versatility. However, in applications that require extremely high dispersion, such as paints for color filters and inkjet inks, sufficient dispersion is often not obtained unless a dispersion resin is used in combination. There remains a problem that the compatibility with the additive and the degree of freedom of the final paint and ink composition are narrowed.
JP 7-268268 A Japanese Patent Laid-Open No. 2001-192595 JP 2001-172530 A

  The present invention provides an organic dye derivative having a basic functional group or a triazine derivative having a basic functional group having excellent dispersibility and storage stability without the above problems, an organic pigment, and an organic solvent in the presence of an acid. The present invention relates to a method for producing an organic pigment dispersion that has been subjected to adsorption treatment.

That is, the present invention relates to an organic pigment derivative having a basic functional group or a triazine derivative having a basic functional group and an organic pigment in an organic solvent having a dielectric constant of 15 or more in the presence of an acid having a molecular weight of 300 or less. In addition, the present invention relates to a method for producing a dispersion, wherein the pigment is dispersed without using a dispersion resin .

  The dispersion of the organic pigment obtained by the present invention has a very good dispersion as compared with a dispersion in which an organic dye having a basic functional group or a triazine derivative is not added, and a dispersion in which the derivative is not used in combination with an acid. And storage stability.

  As the organic pigment used in the present invention, various pigments described in the color index used for printing ink, paint, etc. are used, phthalocyanine series, quinacridone series, benzimidazolone series, anthraquinone series, dioxazine series, Examples include diketopyrrolopyrrole, anthanthrone, indanthrone, flavanthrone, perinone, perylene, isoindoline, isoindolinone, and azo. The organic pigment is exemplified in more detail as follows. Insoluble azo pigments such as toluidine red, toluidine maroon, Hansa yellow, benzidine yellow, pyrazolone red, soluble azo pigments such as risor red, helio bordeaux, pigment scarlet, permanent red 2B, vat dyes such as alizarin, indanthrone, thioindigo maroon Derivatives from dyes, phthalocyanines such as phthalocyanine blue and phthalocyanine green, quinacridones such as quinacridone red and quinacridone magenta, perylenes such as perylene red, perylene scarlet and perylene black, isoindolinone yellow and isoindolinone orange Pyranthrone series such as indolinone, pyranthrone red, pyranthrone orange, thioindigo, condensed azo, benzimidazolone Other pigments include flavanthrone yellow, acylamide yellow, quinophthalone yellow, isoindoline yellow, nickel azo yellow, copper azomethine yellow, perinone orange, anthrone orange, dianthraquinonyl red, dioxazine violet, diketopyrrolopyrrole Etc. can be illustrated.

More specific examples of such pigments by color index (CI) numbers are as follows. C. I. Pigment Yellow 12, 13, 14, 17, 20, 24, 74, 83, 86, 93, 109, 110, 117, 125, 128, 137, 138, 139, 147, 148, 150, 151, 153, 154, 155, 166, 168, 180, 184, 185, C.I. I. Pigment orange 16, 36, 43, 51, 55, 59, 61, C.I. I. Pigment Red 9, 48, 49, 52, 53, 57, 97, 122, 123, 149, 168, 177, 180, 192, 202, 206, 207, 209, 215, 216, 217, 220, 223, 224, 226, 227, 228, 238, 240, 254, 255, C.I. I. Pigment violet 19, 23, 29, 30, 37, 40, 42, 50, C.I. I. Pigment Blue 15, 15: 1, 15: 3, 15: 6, 16, 22, 60, 64, 80, C.I. I. Pigment green 7, 36, C.I. I. Pigment brown 23, 25, 26, C.I. I. Examples thereof include pigment blacks 31 and 32. Considering the adsorptivity and desorption property of the organic dye derivative or triazine derivative, it is preferable to use an organic pigment that has not been subjected to surface treatment such as rosin treatment. Further, the particle size of the organic pigment is not particularly limited, but is preferably 0.01 to 1 μm, and particularly 0.01 to 0.00 μm, as in the organic pigment particle size range used for ordinary inks and paints. 1 μm is preferred. However, the particle size referred to here indicates an average primary particle size measured by an electron microscope or the like.

式中の記号は下記の意味を表す。
Ｑ₁；有機色素残基、アントラキノン残基またはアミノ基を有するアリール基
Ｘ_１；直接結合，−ＣＯＮＨ−Ｙ_２−，−ＳＯ₂ ＮＨ−Ｙ_２- または−ＣＨ₂ ＮＨＣＯＣＨ₂ ＮＨ−Ｙ_１ −（Ｙ_２；置換基を有してもよいアルキレン基またはアリーレン基を表す。）
Ｙ_１；−ＮＨ−または−Ｏ−
Ｚ_１；水酸基、アルコキシ基または下記一般式（２）で示される基で、ｎは１〜４の整数を表す。またｎ＝１の場合、−ＮＨ−Ｘ_１−Ｑ_１であってもよい。
Ｒ_１、Ｒ_２；それぞれ独立に置換もしくは無置換のアルキル基
ｍ；１〜６の整数
一般式（２）

式中の記号は下記の意味を表す。
Ｙ₃；−ＮＨ−または−Ｏ−
Ｒ_３、Ｒ_４；それぞれ独立に置換もしくは無置換のアルキル基またはＲ_３とＲ_４ とが一体となって形成されたヘテロ環。
ｏ；１〜６の整数。
一般式（３）

式中の記号は下記の意味を表す。
Ｑ₂；有機色素残基またはアントラキノン残基
Ｘ_２；直接結合、−ＣＯＮＨ−Ｙ_５−，−ＳＯ₂ＮＨ−Ｙ_５−または−ＣＨ₂ＮＨＣＯＣＨ₂ＮＨ−Ｙ_５−（Ｙ_５は置換基を有してもよいアルキレン基またはアリーレン基を表す。）
Ｙ_４；下記一般式（４）で示される基
ｐ；１〜４の整数。
一般式（４）

式中の記号は下記の意味を表す。
Ｒ_５、Ｒ_６；それぞれ独立に置換もしくは無置換のアルキル基。
ｑ；１〜６の整数。
上記一般式（１）のＱ_１、（３）のＱ_２における有機色素残基としてはフタロシアニン系色素、アゾ系色素、キナクリドン系色素、ジオキサジン系色素、アントラピリミジン系色素、アンサンスロン系色素、インダンスロン系色素、フラバンスロン系色素、ペリレン系色素、ペリノン系色素、チオインジコ系色素、イソインドリノン系色素、トリフェニルメタン系色素等の顔料または染料が挙げられる。上記一般式（１）のＱ₁ におけるアミノ基を有するアリール基としては、例えばアミノフェニル基、アミノナフチル基などが挙げられ、この時ベンゼン環にはアミノ基に加え、他の置換可能な場所にハロゲン基、アミノ基、ニトロ基、水酸基、カルボキシル基、スルホン酸基、アルコキシ基、置換または無置換のアルキル基の何れかの置換基を有してもよい。 The organic dye derivative having a basic functional group and the triazine derivative having a basic functional group used in the present invention are represented by the following general formula (1) or (3).
General formula (1)

The symbol in a formula represents the following meaning.
Q ₁ ; aryl group having an organic dye residue, anthraquinone residue or amino group X ₁ ; direct bond, —CONH—Y ₂ —, —SO ₂ NH—Y ₂ — or —CH ₂ NHCOCH ₂ NH—Y ₁ — (Y ₂ represents an alkylene group or an arylene group which may have a substituent.)
Y ₁ ; —NH— or —O—
Z ₁ ; a hydroxyl group, an alkoxy group or a group represented by the following general formula (2), and n represents an integer of 1 to 4. In the case of n = 1, it may be —NH—X ₁ -Q ₁ .
R ₁ and R ₂ ; each independently a substituted or unsubstituted alkyl group m; an integer of 1 to 6 (2)

The symbol in a formula represents the following meaning.
Y ₃ ; —NH— or —O—
R ₃ and R ₄ each independently a substituted or unsubstituted alkyl group or a heterocycle formed by combining R ₃ and R ₄ together.
o; an integer of 1-6.
General formula (3)

The symbol in a formula represents the following meaning.
Q ₂ ; organic dye residue or anthraquinone residue X ₂ ; direct bond, —CONH—Y ₅ —, —SO ₂ NH—Y ₅ — or —CH ₂ NHCOCH ₂ NH—Y ₅ — (Y ₅ represents a substituent) Represents an alkylene group or an arylene group which may have.)
Y ₄ ; group p represented by the following general formula (4); an integer of 1 to 4.
General formula (4)

The symbol in a formula represents the following meaning.
R ₅ and R ₆ each independently represents a substituted or unsubstituted alkyl group.
q; an integer of 1-6.
Examples of the organic dye residue in Q ₁ of the general formula (1) and Q ₂ of (3) include phthalocyanine dyes, azo dyes, quinacridone dyes, dioxazine dyes, anthrapyrimidine dyes, anthanthrone dyes, Examples thereof include pigments or dyes such as danslon dyes, flavanthrone dyes, perylene dyes, perinone dyes, thioindico dyes, isoindolinone dyes, and triphenylmethane dyes. Examples of the aryl group having an amino group in Q ₁ of the general formula (1) include an aminophenyl group and an aminonaphthyl group. At this time, in addition to the amino group, the benzene ring can be substituted at other substitutable positions. You may have a substituent in any one of a halogen group, an amino group, a nitro group, a hydroxyl group, a carboxyl group, a sulfonic acid group, an alkoxy group, a substituted or unsubstituted alkyl group.

  Adsorption treatment of an organic dye derivative having a basic functional group or a triazine derivative having a basic functional group onto an organic pigment is carried out by subjecting an organic dye derivative having a basic functional group or a triazine derivative having a basic functional group to the presence of an acid. Then, the adsorption treatment proceeds by dissolving in an organic solvent and adding and mixing the organic pigment into the solution. Then, by adsorbing an organic pigment derivative having a basic functional group or a triazine derivative having a basic functional group to an organic pigment, the basic functional groups of the organic pigment or triazine derivative introduced on the surface of the organic pigment are adsorbed. It seems that deaggregation occurs due to charge repulsion.

  As the organic solvent used in the present invention, a polar solvent having a dielectric constant of 15 or more, preferably 20 or more is used. When the dielectric constant is less than 15, the solubility of the organic dye derivative having a basic functional group or the triazine derivative having a basic functional group is remarkably lowered. As long as the dielectric constant satisfies the above conditions, there is no particular limitation. Specifically, alcohols such as methanol, ethanol, propyl alcohol, and butanol, 1,2-ethanediol, 1,2-propanediol, Glycol solvents such as 1,3-propanediol, 1,4-butanediol, diethylene glycol, ketones such as acetone and methyl ethyl ketone, other N-methylpyrrolidone, acetonitrile, N, N-dimethylformamide, sulfolane, dimethyl sulfoxide, etc. Is mentioned. These solvents can be used singly or in combination of two or more, but in use, it is preferable to contain a protic solvent such as alcohols or glycols. Moreover, viscous glycerin etc. can also be melt | dissolved and used for the said solvent at normal temperature.

  In the present invention, the acid added to dissolve the organic dye derivative having a basic functional group and the triazine derivative having a basic functional group is obtained by reaction of hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, strong acid and weak base. Inorganic compounds such as salts, organic acids such as carboxylic acids and sulfonic acids can be used. Organic acids are preferred, and carboxylic acids are particularly preferred. Further, these acids have a molecular weight of 300 or less. Preferably it is 200 or less.

  As the addition amount of the acid used in the present invention, 0.1 to 10 equivalents is added with respect to the acidic functional group amount contained in the organic dye derivative having a basic functional group or the triazine derivative having a basic functional group. I can do it. More preferably, it is 0.5 to 5 equivalents.

  The concentration of the organic solvent solution of the organic dye derivative having a basic functional group or the triazine derivative having a basic functional group is 1 to 100 mmol / L, and preferably 1 to 50 mmol / L. Most preferably, it is 5-20 mmol / L.

  The slurry concentration of the organic solvent dispersion of the organic pigment varies depending on the characteristic values specific to the organic pigment, the type of organic dye derivative having a basic functional group or the triazine derivative having a basic functional group, the amount added, etc. Therefore, it is not particularly limited, but 5 to 50% is preferable.

  The disperser used for the adsorption treatment is not particularly limited. For example, a paint conditioner (manufactured by Red Devil), a ball mill, a sand mill (such as “Dynomill” manufactured by Shinmaru Enterprises), an attritor, a pearl mill (Such as “DCP mill” manufactured by Eirich), coball mill, basket mill, homomixer, homogenizer (such as “Creamix” manufactured by M Technique), wet jet mill (“Genus PY” manufactured by Genus, “Nanomizer manufactured by Nanomizer”) Or the like. In view of cost, processing capability, etc., it is preferable to use a media type dispersing machine. As the media, glass beads, zirconia beads, alumina beads, magnetic beads, stainless beads, etc. can be used.

  In order to exhibit the performance of the organic pigment adsorbed by the disperser at the same time, it is preferable that the dispersed particle size is reduced to 0.5 μm or less, preferably 0.2 μm or less. The dispersed particle size here is an average particle size (D50 value) measured by a general particle size distribution meter, for example, a dynamic light scattering type particle size distribution meter (for example, “Microtrac UPA” manufactured by Nikkiso Co., Ltd.). is there.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not specifically limited to a following example, unless the summary is exceeded. In this example, parts represent parts by weight. In addition, the measurement of the dispersion | distribution particle diameter of the organic pigment dispersion obtained by the Example and the comparative example and evaluation of storage stability were performed with the following method.

  The average particle size (D50 value) was measured using a dynamic light scattering type particle size distribution meter ("Microtrack UPA" manufactured by Nikkiso Co., Ltd.). As the diluting solvent at the time of measurement, the same organic solvent used in each example was used.

  The storage stability was evaluated from the change in particle diameter after storing an organic solvent dispersion of an organic pigment at 40 ° C. for 10 days.

After adding 89.9 parts of methanol, 0.1 part of hydrogen chloride and 0.5 part of the dispersant represented by the general formula (5) to a glass bottle and mixing and stirring, LIONOL BLUE E (manufactured by Toyo Ink Manufacturing Co., Ltd.) 9.5 parts was added and dispersed with a paint shaker using zirconia beads as a medium to obtain dispersion A.
General formula (5)

  Add 89.9 parts of n-butanol, 0.1 part of glacial acetic acid and 0.5 part of the dispersant represented by the general formula (5) to the glass bottle, and after mixing and stirring, add 9.5 parts of LIONOL BLUE E. Then, zirconia beads were dispersed with a paint shaker as a medium to obtain dispersion B.

  To the glass bottle, 79.8 parts of ethylene glycol, 0.2 part of glacial acetic acid, 1.0 part of a dispersant represented by the general formula (5) were added, and after mixing and stirring, 19.0 parts of LIONOL BLUE E were added, Dispersion C was obtained by dispersing zirconia beads as a medium using a paint shaker.

In a glass bottle, 89.9 parts of methanol, 0.1 part of glacial acetic acid and 0.5 part of a dispersant represented by the general formula (6) were added, mixed and stirred, and then LIONOL RED 5620 (manufactured by Toyo Ink Manufacturing Co., Ltd.) was added. 9.5 parts was added and dispersed with a paint shaker using zirconia beads as a medium to obtain dispersion D.
General formula (6)

After adding 89.9 parts of methanol, 0.1 part of glacial acetic acid and 0.5 part of the dispersant represented by the general formula (7) to a glass bottle and mixing and stirring, LIONOL GREEN 6YK (manufactured by Toyo Ink Manufacturing Co., Ltd.) 9.5 parts was added and dispersed with a paint shaker using zirconia beads as a medium to obtain dispersion E.
General formula (7)

In a glass bottle, 89.9 parts of methanol, 0.1 part of glacial acetic acid and 0.5 part of a dispersant represented by the general formula (8) were added, mixed and stirred, and then HOSTAPERM YELLOW H5G (manufactured by Clariant) was added. .5 parts was added and dispersed with a paint shaker using zirconia beads as a medium to obtain dispersion F.
General formula (8)

To a glass bottle, 89.9 parts of ethanol, 0.1 part of glacial acetic acid and 0.5 part of a dispersant represented by the general formula (9) were added, mixed and stirred, and then HOSTPERM VIOLET BL (manufactured by Clariant) was added. Five parts were added and dispersed with a paint shaker using zirconia beads as a medium to obtain dispersion G.
General formula (9)

  To a glass bottle, 84.8 parts of methanol, 0.1 part of glacial acetic acid and 0.5 part of a dispersant represented by the general formula (7) were added, mixed and stirred, and then PALIOGEN MAROON L3980 (manufactured by BASF) was added to 9.5. In addition, zirconia beads were dispersed with a paint shaker as a medium, and dispersion H was obtained.

  As shown in the table, the organic pigment dispersion of the present invention showed a fine dispersed particle size and good storage stability compared to the comparative example.

Comparative Example 1

  90 parts of methanol and 10 parts of LIONOL BLUE E were added to a glass bottle, and dispersed in a paint shaker using zirconia beads as a medium to obtain dispersion I.

Comparative Example 2

  89.9 parts of methanol, 0.1 part of glacial acetic acid, and 10.0 parts of LIONOL BLUE E were added to a glass bottle, and dispersed with a paint shaker using zirconia beads as a medium, to obtain a dispersion J.

Comparative Example 3

  Add 90 parts of methanol and 0.5 part of the dispersant represented by the general formula (5) to the glass bottle, mix and stir, add 9.5 parts of LIONOL BLUE E, and disperse with a paint shaker using zirconia beads as a medium. Dispersion K was obtained.

Comparative Example 4

  Add 80 parts of methanol, 10 parts of Solsperse 20000 (manufactured by Avicia, alcohol-soluble resin type dispersant) and 10 parts of HOSTAPERM YELLOW H5G to a glass bottle, and disperse with a paint shaker using zirconia beads as a medium to obtain dispersion L It was.

Comparative Example 5

  Add 90 parts of methanol and 0.5 part of the dispersant represented by the general formula (6) to a glass bottle, and mix and stir. Then, 9.5 parts of LIONOL RED 5620 and zirconia beads as a medium are dispersed in a paint shaker. M was obtained.

Comparative Example 6

In a glass bottle, 80 parts of methanol, 10 parts of Solsperse 20000, and 10 parts of LIONOL RED 5620 were added and dispersed with a paint shaker using zirconia beads as a medium to obtain dispersion N.

Claims (3)

A triazine derivative having an organic dye derivative or a basic functional group having a basic functional group, an organic pigment, the presence of a molecular weight of 300 or less acid, in which dielectric constant is adsorption treatment in an organic solvent at least 15 And a method for producing a dispersion, wherein the pigment is dispersed without using a dispersion resin .  2. The method according to claim 1, wherein the organic solvent contains a protic solvent.  The production method according to claim 1 or 2, wherein the adsorption treatment is performed using a media-type disperser.