JPH0735484B2 - Method for dispersing pigment and pigment composition - Google Patents

Description

Detailed Description of the Invention

"Purpose of Invention" (Field of Industrial Application) The present invention relates to a pigment dispersion method and a pigment composition having excellent suitability for use, particularly non-aggregation property and non-crystallinity. (Prior Art) Generally, a practically useful pigment that exhibits a clear color tone and high tinting strength in various coating compositions is composed of fine particles. However, when dispersed in non-aqueous vehicles such as offset inks, gravure inks and paints, fine particles of pigments make it difficult to obtain stable dispersions and have a significant impact on the manufacturing process and the value of the resulting products. It is known to cause various problems. For example, dispersions containing pigments consisting of fine particles often have high viscosities and are difficult to transport from the product disperser, and in the worse case, gelation occurs during storage, making them unusable. May be. Further, when different kinds of pigments are mixed and used, color unevenness or a marked decrease in coloring power may occur in a color-developed product due to phenomena such as color separation due to aggregation and sedimentation. Furthermore, the coating surface of the color-developed product may have poor gloss, poor leveling, and other defective states. Although not directly related to pigment dispersion, in some organic pigments, energy-unstable pigment crystal particles change their size and morphology in a non-aqueous vehicle and move to a stable state. The product value may be impaired due to a marked change in hue, a decrease in coloring power, or the generation of coarse particles. For the purpose of improving the non-aggregation property and crystal stability of pigments, many proposals have been made so far, centering on copper phthalocyanine pigments and quinacridone pigments. For example, as shown in Japanese Patent Publication No. 41-2466 and USP2761865, it is obtained by using an organic pigment as a mother bone nucleus and introducing a substituent such as a sulfone group, a sulfonamide group, an aminomethyl group or a phthalimidomethyl group into a side chain. It is a method of mixing compounds. These methods are remarkably advantageous in terms of the non-aggregation property of the pigment in the non-aqueous vehicle, the crystal stability and the like, and the ease of manufacturing the pigment composition. However, much research has not been done on the method of mixing azo pigments. Japanese Patent Publication 45-11026 and Japanese Patent Publication 53-3
In Japanese Patent No. 5090, a method is proposed in which an azo dye alkaline earth metal sulfonate and an organic amine salt are mixed. (Problems to be Solved by the Invention) The present inventors have studied to solve various problems occurring in non-aqueous vehicles such as offset inks, gravure inks and paints as described above, and have found practically excellent pigments. Invented a dispersion method. [Structure of the Invention] (Means for Solving the Problems) That is, the present invention provides a method for dispersing a pigment or a pigment dispersion method using 0.3 to 30 parts by weight of an azo compound represented by the following general formula (I) in 100 parts by weight of a pigment It is a composition. In the formula, Q: a residue of an azo dye. A: represents a divalent linking group shown below. -O -, - NR '-, - S -, - CO -, - SO 2 -, - CR'
R "-, -SO ₂ NR'-, -CONR'-, -CH ₂ NH-, -CH ₂ N
HCOCH ₂ -A combination thereof or a saturated or unsaturated alkylene group having 1 to 20 carbon atoms bonded to each of the above divalent bonding groups (provided that the alkylene group is not directly bonded to another alkylene group in the formula), or Represents an arylene group. R'and R "represent a hydrogen atom, or an alkyl group or aryl group having 1 to 20 carbon atoms. R _{1 to} R ₄ : hydrogen atom, a saturated or unsaturated alkyl group or aryl group having 1 to 20 carbon atoms, Or represents a heterocycle containing a nitrogen, oxygen or sulfur atom, n, k, p, m: an integer of 1 to 4, l, r: an integer of 0 to 4, provided that l and r are not 0 at the same time. When the azo compound represented by the general formula (I) according to the invention is mixed with the pigment, the pigment is not assembled in the non-aqueous vehicle more than when the azo compound is mixed with the alkaline earth metal sulfonate or the organic amine salt. It was clarified that the effect on the properties, crystal stability, etc. was remarkably increased.In addition, the azo compound represented by the general formula (I) was filtered, compared with alkaline earth metal sulfonates and organic amine salts.
It became clear that washing with water is very easy and there is no loss during washing, which is extremely advantageous in manufacturing. Incidentally, JP-A-61-246260 reports an example in which A in the present invention does not exist, that is, an alkylamine such as tetramine or triamine is directly bonded to a dye. However, the anchoring effect of this dispersant on the dye to be adsorbed is insufficient as compared with the dispersant of the present invention, and as a result, stains of hue occur, dispersibility, gloss, density, viscosity, and stability over time are poor. No satisfactory effect has been obtained. Further, Japanese Patent Publication No. 56-166266 discloses the general formula (I) of the present invention.
It has been shown that the dispersant is effective as described above when 1 = 0 and r = 0 in. In the present invention, even when l is 0 to 4 and r is 0 to 4 (l and r do not take 0 at the same time), that is, when the alkylamine is repeatedly repeated 2 or more, the dispersion is equal to or more than that. It was confirmed that the agent was effective. Typical alkylamines used to make the azo pigment dispersants of the present invention are N-beef tallow-N- (3-aminopropyl).
-1,3 diaminopropane, N- (3-tallow aminopropyl) -1,3 diaminopropane, (N- (N-3-tallow aminopropyl) -3-aminopropyl) -1,3 diaminopropane, N- Oleyl-N- (3-aminopropyl)-
Examples thereof include 1,3 diaminopropane and N-stearyl-N- (3-aminopropyl) -1,3-diaminopropane. The azo compound represented by the general formula (I) can be produced by the following three methods. The first method is an aromatic amine having the general formula: (In the formula, R ₅ and R ₆ are independently a hydrogen atom, -OCH ₃ , -Cl,
-SO ₃ H, -NO _2, represent either an alkyl group. R ₀ in the general formula (I) is Represents ) Is diazotized by a conventional method and is coupled with an industrially useful coupler such as phenols, naphthols, acetoacetic anilides, pyrazolones and oxyquinolines. The second method is, for example, the following general formulas (III), (IV),
(V), (VI), (VII) (Wherein R ₀ , R ₅ , R ₆ are the same as R ₀ , R ₅ , and R _{6 in the} general formula (II).) Industrially useful bases are diazotized to a coupling component having Obtained by coupling. The third method is to use an azo compound as a raw material, for example, to convert it into a chlorosulfonate or carboxylic acid chloride, and then react it with a compound of the general formula (VIII) in the presence of a solvent. (In the formula, R _{1 to} R ₄ and n, k, p and l, r are the same as the corresponding symbols in the general formula (I)), and can be obtained by a dehydrochlorination reaction with an amine represented by the formula. In this method, 1 to 4 substituents are introduced, which will be described in the production example. Two or more substituents can also be introduced by the first and second methods. For example, it can be obtained by coupling an aromatic amine of the general formula (II) with a coupler component as described below. (Meanings same as R _0, R _5, R ₆ of formula in R _0, R _5, R ₆ has the general formula (II).) The pigment in the present invention, the soluble and insoluble azo pigments, condensed azo pigments Phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, perylene / perinone pigments, dioxazine pigments, vat dye pigments, basic dye pigments, etc. Inorganic pigments such as carbon black, titanium oxide, yellow lead, cadmium yellow, cadmium red, red iron oxide, iron black, zinc white, navy blue, and ultramarine can also be used. The amount of the compound represented by formula (I) according to the present invention to be added to the pigment is preferably 0.3 to 30 parts by weight based on 100 parts by weight of the pigment. If the amount is less than 0.3 parts by weight, the effect of the compound represented by the general formula (I) cannot be obtained, and if the amount is more than 30 parts by weight, the effect of the amount used cannot be obtained. The method of using the compound represented by formula (I) according to the present invention is as follows. That is, 1. A pigment composition obtained by previously mixing a pigment and a compound represented by the general formula (I) is added to a non-aqueous vehicle and dispersed. 2. A pigment and a compound represented by the general formula (I) are separately added to and dispersed in a non-aqueous vehicle. 3. The pigment and the compound represented by the general formula (I) are separately dispersed in a non-aqueous vehicle in advance, and the resulting dispersion is mixed. In this case, the compound represented by the general formula (I) may be dispersed only in the solvent. 4. After dispersing the pigment in the non-aqueous vehicle, add the compound represented by the general formula (I) to the obtained dispersion. There are four methods, etc., and any of these can achieve the desired effect. As a method for preparing the pigment composition shown in the above 1, the desired effect can be obtained by simply mixing the pigment powder and the powder of the compound represented by the general formula (I) according to the present invention.
Mechanically mixing with a kneader, roll, attritor, supermill, various crushers, etc., or adding a solution containing a compound represented by the general formula (I) according to the present invention to a suspension system of water or an organic solvent for a pigment. Then, the compound represented by the general formula (I) is deposited on the surface of the pigment, or
Better results can be obtained by performing a close mixing method such as co-dissolving the organic pigment and the compound represented by the general formula (I) in a solvent having a strong dissolving power such as sulfuric acid and coprecipitating with a poor solvent such as water. You can get it. In the use of the pigments shown in the above 2 to 4 and the compound represented by the general formula (I), the pigment or the compound represented by the general formula (I) is dispersed in a non-aqueous vehicle or a solvent. The pigment can be well dispersed by using a dissolver, a high speed mixer, a homomixer, a kneader, a roll mill, a sand mill, an attritor or the like as a dispersing machine for mixing and the like. Therefore, according to the present invention, offset ink vehicles such as various rosin-modified resins, lime rosin varnishes, gravure inks such as polyamide resin varnishes or vinyl chloride resin varnishes, nitrocellulose lacquers, permanent drying or baking paints of aminoalkyd resins, acrylic lacquers. In non-aqueous vehicles such as amino acrylic resin baking paints and urethane resin paints, it shows good fluidity such as lower viscosity and structural viscosity of the dispersion than when pigment is used alone, and at the same time, color separation It is possible to obtain a beautiful product because the printed matter or the coating film has a good gloss without problems such as crystal change. An outline of the synthetic method of a typical compound represented by the general formula (I) will be described below as a production example. Production Example [1] β-oxynaphthoic acid was heated and stirred under reflux with equimolar thionyl chloride in benzene or acetone for 1 hour to synthesize an acid chloride, and after the reaction was completed, (N- (N-3-beef tallow Aminopropyl) -3-aminopropyl-1,3-diaminopropane was added, and the mixture was further heated and stirred under reflux for 1 hour to obtain the following coupler component. (However, beef tallow was represented by having 18 carbon atoms.) This coupling component was coupled with the diazo component to obtain an azo dye. Comparative Example of Production Example [1] N-beef tallow-1, in place of the amine used in Production Example [1],
The following coupler components were obtained in the same manner as in Production Example [1] using 3 diaminopropane. The following azo dye was obtained using this coupling component in the same manner as in Production Example [1]. Production Example [2] The following coupler component was obtained in the same manner as in Production Example [1] using (N-3-beef tallow aminopropyl) -1,3 diaminopropane. The following azo dye was obtained by coupling the diazo component with this coupling component. Production Example [3] P-Nitrobenzoyl chloride in N- (N-
(Oleylaminopropyl) -3-aminopropyl)-
1,3 Diaminopropane was stirred under reflux for 1 hour to synthesize a carboxylic acid amide, and then the nitro group was reduced by a conventional method to obtain the following diazo component. This base was diazotized according to a conventional method and coupled with a coupling component to obtain the following azo dye. Production Example [4] p-Acetylaminosulfonyl Chloride and Production Example [1]
The sulfone amide obtained by heating and stirring the amine used in 1) under reflux for 2 hours in benzene or acetone was hydrolyzed by boiling under reflux for 1 hour in diluted hydrochloric acid to obtain the following diazo component. This base was diazotized according to a conventional method to give a production example [1].
The following azo dye was obtained by coupling with the coupling component of. Production Example [5] The base of Production Example [4] and an equimolar amount of diketene were heated and stirred in xylene under reflux for 1 hour to obtain the following coupling component. Various bases were diazotized with this coupling component and coupled to obtain the following azo dye. Comparative Example of Production Example [5] The amine used in Production Example [1] and an equimolar amount of diketene were heated and stirred in xylene under reflux for 1 hour to obtain the following coupling component. The following azo dye was obtained by coupling the diazo component with this coupling component. Production Example [6] Azo dye having the following structure And an equivalent mole of thionyl chloride are heated and stirred in xylene under reflux for 2 hours to form an acid chloride, and then the amine used in Production Example [1] is added, and further heated and stirred under reflux for 1 hour. Azo dye of Production Example [7] Azo dye having the following structure And an equivalent mole of thionyl chloride are heated and stirred in xylene under reflux for 2 hours to form an acid chloride, and then the amine used in Production Example [2] is added, and further heated and stirred under reflux for 1 hour. Azo dye of Production Example [8] 10 parts of an azo dye having the following structure was stirred with 50 parts of chlorosulfonic acid at 50 ° C. for 1 hour, poured into ice water, filtered, and washed with water to obtain a water cake of chlorosulfonate. Ice water 20
The amine used in Production Example [1] was added dropwise to 0 part as a slurry, and the mixture was stirred at 10 to 20 ° C. for 5 hours to obtain an azo dye having the following structure. Chlorsulfone group was analyzed by reductive decomposition of azo group,
It was revealed that two naphthalene nuclei and one benzene nuclei were introduced. Production example

[9] Azo dye having the following structure Was heated and stirred under reflux for 2 hours in twice the molar amount of thionyl chloride and xylene to give an acid chloride, and then the production example [2]
The amine used in 1. was added, and the mixture was heated and stirred under reflux for 2 hours to obtain an azo dye having the following structure. Examples and comparative examples will be described below. The chemical structure of each compound indicated by the alphabet corresponds to that shown in the production example. Example 1 CIPigment Yellow 83 was blended in a vinyl chloride varnish for gravure so that the pigment content was 10%, and dispersed by a sand mill to obtain a pigment dispersion. Comparative Example A powder of compound (e) was added to the obtained pigment dispersion by CI Pigmen.
The content was adjusted to 10% by weight with respect to t Yellow 83 and uniformly stirred with a dissolver to prepare a gravure ink, and the viscosity was measured and compared with the viscosity of the above pigment dispersion (comparative example). The results are shown in Table 1, and those according to the present invention have excellent fluidity. In addition, the printed matter printed with the gravure ink also showed excellent effects on the vividness of the color tone, the coloring power, and the gloss. In addition, the dispersion obtained by previously dispersing the compound (e) in a vinyl chloride varnish for gravure with a sand mill was used as a CI Pigment Yell
Even if the weight ratio of ow83 and compound (e) was lowered to 9: 1, the same effect was obtained. Comparative Examples and Examples (2) to (6) In the vinyl chloride varnish for gravure, various pigments alone (comparative examples) were dispersed such that the pigment content was 10% (25% for inorganic pigments) or various pigments were dispersed. After being made to manufacture example 1-9
Gravure ink was prepared by adding various compounds shown in 1 above, and its viscosity was examined. The results are shown in Table 1, and those according to the present invention have excellent fluidity. Also, excellent effects were obtained in terms of the vividness of the color tone, the coloring power, and the gloss of the printed matter printed with the gravure ink. The case where the compound (f ') is used is shown as a comparative example of Example (3). The compound (f) had a greater dispersion effect than the compound (f '). As a comparative example of Example (4), the case of using the compound (a ′) is shown. The dispersion effect of the compound (a) was slightly larger than that of the compound (a '). Example (7) CI Pigmen for amino alkyd resin varnish for baking paint
t Blue-15 was blended so that the pigment content was 6% by weight, and dispersed by a ball mill to obtain a pigment dispersion. (Comparative Example) Further, the compound (i) was dispersed in xylene with an attritor to prepare a concentrated xylene dispersion of the compound (i). Then, the pigment dispersion and the xylene dispersion of the compound (i) were mixed in a weight ratio of CI Pigment Blue-15 to the compound (i) of 9: 1.
Was uniformly mixed with a dissolver to prepare a paint, the viscosity was measured, and the viscosity was compared with that of the above pigment dispersion (comparative example). The results are shown in Table 2, and those of the present invention have excellent fluidity. Further, the same effect can be obtained by adding the powder of the compound (i) to the above pigment dispersion so that the content of the powder is 10% by weight based on the pigment and uniformly mixing with a dissolver. Examples (8) to (13) Aminoalkyd resin varnish for baking paint has a pigment content of 6
% (25% in the case of an inorganic pigment), each pigment alone (comparative example) or after dispersing each pigment, each compound shown in Production Examples 1 to 9 is added to prepare an aminoalkyd paint. Then, the viscosity was measured. The results are shown in Table 2. The aminoalkyd paints according to the examples were excellent in fluidity and crystal stability, and were also excellent in the color of the coating film, the degree of tinting strength, and the gloss. Furthermore, storage stability was also excellent with little change in viscosity increase. Example (14) CI Pigment Blue 15 was added to a nitrocellulose lacquer so that the pigment content was 5.5% by weight, and the mixture was kneaded with three rolls to obtain a pigment dispersion. (Comparative Example) When preparing a pigment dispersion in the same manner as described above, the compound (i) was added to CI Pigment Blue 15 so that the content was 5% by weight before the completion of kneading with three rolls, and the mixture was mixed uniformly. A paint was prepared by mixing with the above, the viscosity was measured, and the viscosity was compared with that of the above pigment dispersion. The results are shown in Table 4, and those according to the present invention have excellent fluidity. Similar results were obtained when the dispersing machine used for preparing the above paint was changed from a three roll mill to a sand mill. Examples (15) to (20) CI Pigment Blue 15 alone (comparative example) was dispersed in a nitrocellulose lacquer such that the pigment content was 5.5%, or C.I.
The viscosity of the paint prepared by adding 5/95 to I. Pigment Blue 15 is shown in Table 3. Similarly, Table 3 shows the test results regarding the viscosity of the nitrocellulose lacquer in combination with other pigments and various compounds according to the present invention. In any case, the one according to the present invention has excellent fluidity, and also has excellent results in gloss, sharpness of color tone and tinting strength in the color-developed coating film. A storage stability test was also conducted on Examples 14 and 17. The storage condition is 50 ° C for 3 months. As is clear from the results in Table 4, all of the products according to the present invention have excellent storage stability. Example (21) Amino acrylic baking paint Amino acrylic baking paint CIPigment Orange 36 alone (comparative example) was dispersed in a varnish so that the pigment content was 6%, or CI Pigment Orange 36 was dispersed, and then compound (k) was added to CIPigment Orange 36. On the other hand, when the fluidity of the paints added so that the ratio was 10/90 was compared, the one according to the present invention showed remarkably excellent results. Also, in the paint prepared by cutting the above-prepared paint using an aluminum paint base prepared in advance with aminoacrylic resin varnish so that the ratio of pigment and aluminum is 1/5, the one according to the present invention has a remarkably clear color tone and excellent gloss. showed that. Example (22) Urethane paint varnish CIPi so that the pigment content in the urethane paint varnish is 10%.
gment Yellow95 alone (comparative example) or CI
After dispersing Pigment Yellow 95, compound (h) was added to CI
When the fluidity of the paint added so that it became 10/90 against Pigment Yellow 95 and the state of the color-developed coating film were compared,
The product according to the present invention was excellent in fluidity and the color tone and gloss of the color-developed coating film. Example (23) Rosin-modified phenolic resin offset ink CIPigment Red 57 was dispersed in a rosin-modified phenolic resin-based offset ink varnish so that the pigment content was 30%, and then compound (a) was dispersed in CI Pigment Red 57. Later, compound (a) was applied to CI Pigment Red 57
An offset ink was prepared by adding it so as to be 15/85, and its fluidity was compared by a parallel plate type viscometer. The one according to the present invention showed remarkably excellent results. Also in the printed matter, the one according to the present invention showed excellent results in vividness of color tone, coloring power and transparency.

Claims (2)

[Claims] 1. A method of dispersing a pigment, wherein 0.3 to 30 parts by weight of an azo compound represented by the following general formula (I) is used in 100 parts by weight of the pigment. In the formula, Q: a residue of an azo dye. A: represents a divalent linking group shown below. -O -, - NR '-, - S -, - CO -, - SO 2 -, - CR'
R "-, -SO ₂ NR'-, -CONR'-, -CH ₂ NH-, -CH ₂ N
HCOCH ₂ -A combination thereof or a saturated or unsaturated alkylene group having 1 to 20 carbon atoms bonded to each of the above divalent bonding groups (provided that the alkylene group is not directly bonded to another alkylene group in the formula), or Represents an arylene group. R'and R "represent a hydrogen atom, or an alkyl group or aryl group having 1 to 20 carbon atoms. R _{1 to} R ₄ : hydrogen atom, a saturated or unsaturated alkyl group or aryl group having 1 to 20 carbon atoms, Or represents a heterocycle containing a nitrogen, oxygen or sulfur atom, n, k, p, m: an integer of 1 to 4, l, r: an integer of 0 to 4, provided that l and r are not 0 at the same time. 2. A pigment composition comprising 100 parts by weight of the pigment and 0.3 to 30 parts by weight of the azo compound of the general formula (I) as set forth in claim 1.