JP2584515B2 - Pigment dispersant and pigment composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a pigment dispersant which provides a pigment dispersion excellent in usability, especially non-aggregation, non-crystallinity and fluidity.

(Prior Art) In general, practically useful pigments that exhibit a vivid color tone and high coloring power in various coating or ink compositions consist of fine particles. However, when the fine pigment particles are dispersed in drainage vehicles such as offset inks, gravure inks and paints, it is difficult to obtain a stable dispersion, which has a significant effect on the production work and the value of the resulting product. It is known to cause various problems.

For example, dispersions containing pigments consisting of fine particles often have high viscosities, which makes it difficult to remove and transport the product from the disperser, or worse, causes gelation during storage and causes use. It can be difficult. When different kinds of pigments are mixed and used, color unevenness or remarkable decrease in coloring power may be caused in a color-developed product due to reduction in color separation or sedimentation due to aggregation. Further, with respect to the surface of the coated film of the colored product, a state defect such as a decrease in gloss and a leveling defect may occur.

Although not directly related to the pigment dispersion, some organic pigments have a phenomenon involving a change in the crystal state of the pigment.

That is, in non-aqueous vehicles such as offset inks, gravure inks, and paints, the crystal particles of energetically unstable pigments change their size and form and shift to a stable state. The commercial value may be impaired due to a decrease in coloring power, generation of coarse particles, and the like.

In order to solve the above various problems, many proposals have been made mainly on copper phthalocyanine and quinacridone pigments.

The contents can be roughly classified into the following two when classified according to the technical method.

The first method involves coating the surface of pigment particles with a colorless compound such as silicon oxide, aluminum oxide and tertiary butyl benzoic acid as disclosed in US Pat.

In the second method, as represented by JP-B-41-2466 and US Pat. No. 2,855,403, a substituent such as a sulfone group, a sulfonamide group, an aminomethyl group or a phthalimidomethyl group is introduced into a side chain using an organic pigment as a parent skeleton. This is a method of mixing the compounds obtained by the above.

The second method has a remarkably large effect on the non-aggregation property and crystal stability of the pigment in the non-aqueous vehicle as compared with the first method, and is extremely advantageous even when judged from the ease of producing the pigment composition. Is the way.

(Problems to be Solved by the Invention) The present invention relates to a pigment composition part and a dispersion method for obtaining a stable dispersion liquid having excellent non-aggregation and fluidity when producing offset inks, gravure inks and paints. Is provided.

[Constitution of the Invention] (Means for Solving the Problem) The present invention relates to a pigment dispersant represented by formula (1) and a pigment composition comprising a pigment and a pigment dispersant represented by formula (1).

Represents

R _{1 to} R ₁₀ represent a hydrogen atom.

p represents an integer of 1 to 3.

X: directly bonded or -SO ₂ NH-, -CONH-, -CH ₂
NHCOCH ₂ NH—, —CH ₂ NH—.

R ₁₁ , R ₁₂ : each independently, a saturated or unsaturated alkyl group or R ₁₁ , R ₁₂ or a single nitrogen atom or containing the nitrogen atom and an oxygen atom, may be substituted with an alkyl group or a hydroxyl group It represents a good 5- or 6-membered ring.

n represents an integer of 1 to 3.

_{Z: -SO 2 -, - CH} 2 representing the NHCOCH ₂ NH-.

R _{13 to} R ₁₆ represent a hydrogen atom.

R ₁₇ represents an alkyl group.

In the formula (I), R _{1 to} R ₁₀ each independently represent a hydrogen atom, a halogen atom, alkyl, alkoxy,
Represents a cyano, sulfonyl, carboxyl, dialkylamino, halogenoalkyl, alkoxycarbonyl, carbamoyl, alkylmercapto or sulfamoyl group, preferably hydrogen, chlorine, bromine, cyano, methyl, ethyl, trifluoromethyl, dimethylamino, aethylamino, Sulfonyl, carboxyl, methoxy,
Ethoxy, tert-butyl or methoxycarbonyl.

In the formula (I), The amine component used to form
Dimethylamine, diethylamine, N-ethylisopropylamine, N-ethylpropylamine, N-methylbutylamine, N-methylisobutylamine, N-butylethylamine, N-tert-butylethylamine, diisopropylamine, dipropylamine, N-sec -Butylpropylamine, dibutylamine, di-sec-butylamine, diisobutylamine, N-isobutyl-sec-butylamine, diamylamine, diisoamylamine, dihexylamine, di (2-ethylhexyl) amine, dioctylamine, N-methyloctadecylamine , Didecylamine, diallylamine, N-ethyl-1,2-dimethylpropylamine, N-methylhexylamine, 2-hydroxymethylaminoethanol, dioleylamine, distearylamine, N, N-dimethylaminomethylamine, N, N- The Chill aminoethyl amine, N, N-dimethylaminopropyl amine, N, N-dimethylamino-amyl amine, N, N-dimethylamino-butyl amine, N, N-diethylaminoethyl amine,
N, N-diethylaminopropylamine, N, N-diethylaminohexylamine, N, N-diethylaminobutylamine, N, N-diethylaminopentylamine, N, N-dipropylaminobutylamine, N, N-dibutylaminopropylamine, N , N-dibutylaminoethylamine, N, N-dibutylaminobutylamine, N, N-diisobutylaminopentylamine, N, N-methyl-laurylaminopropylamine,
N, N-ethyl-hexylaminoethylamine, N, N-distearylaminoethylamine, N, N-dioleylaminoethylamine, N, N-distearylaminobutylamine, piperidine, 2-pipecoline, 3-pipecoline, 4-pipecoline , 2,4-Lupetidine, 2,6-lipetidine, 3,5-lupetidine, 3-piperidinemethanol, pipecolic acid, isonipecotinic acid, methyl isonicopetinate, ethyl isonicopetinate, 2-piperidineethanol, pyrrolidine, 3-hydroxypyrrolidine, N-aminoethylpiperidine, N-aminoethyl-4-pipecholine, N-aminoethylmorpholine, N-aminopropylpiperidine, N-aminopropyl-
2-Pipecoline, N-aminopropyl-4-pipecoline, N
-Aminopyropirmophorin, N-methylpiperazine, N-
Butylpiperazine, N-methylhomopiperazine, 1-cyclopentylpiperazine, 1-amino-4-methylpiperazine, 1-cyclopentylpiperazine and the like.

Although there are several synthetic routes for producing the pigment dispersant according to the present invention, a typical production method will be outlined with reference to the pigment dispersant represented by the formula (II) or (III) as an example. These are shown below as 1) and 2).

1) First, a compound represented by the formula (IV) is produced by reacting benzonitrile with succinate new dimethyl ester.

Next, the compound represented by the formula (IV) is chlorosulfonated by a conventional method to produce a compound represented by the formula (V).

Next, the compound represented by the formula (V) is reacted with N-methylpiperazine to produce a pigment dispersant represented by the formula (II).

2) First, p-cyanobenzoyl chloride is reacted with N, N-dimethylaminopropylamine to produce a compound represented by the formula (VI).

Next, the compound represented by the formula (VI) is reacted with dimethyl succinate to produce a pigment dispersant represented by the formula (III).

The pigment dispersant represented by the formula (II) is, for example,
First, the compound represented by the formula (VII) can be produced, and then the pigment dispersant represented by the formula (III) represented by the above 2) can be produced in the same manner as in the production of the pigment dispersant. It is advantageous to synthesize by the method described in 1) above.

The pigment dispersant obtained in the present invention exhibits an excellent dispersing effect on almost all commercially available pigments. For example, azo pigments such as diketopyrrolopyrrole pigments, soluble and insoluble azo pigments, condensed azo pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, perylene / perinone pigments, dioxazine pigments,
Anthraquinone pigments, dianthraquinonyl pigments, anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, flavanthrone pigments, pyranthrone pigments, vat dye pigments, basic dye pigments, etc. It can be used for organic pigments and inorganic pigments such as carbon black, titanium oxide, horizontal lead, cadmium yellow, cadmium red, red iron oxide, iron black, zinc white, navy blue and ultramarine.

The blending of the pigment dispersant obtained in the present invention with the pigment is as follows:
0.1 to 30 parts by weight is preferable for 100 parts by weight of the pigment. If the amount is less than 0.1 part by weight, the effect of the pigment dispersant obtained in the present invention 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 pigment dispersant according to the present invention includes, for example, the following method.

1. A pigment composition obtained by previously mixing a pigment and a pigment dispersant is added to a non-aqueous vehicle or the like and dispersed.

2. The pigment and the pigment dispersant are separately added and dispersed in a non-aqueous vehicle or the like.

3. The pigment and the pigment dispersant are separately dispersed in a non-aqueous vehicle or the like, and the resulting dispersion is mixed.

 In this case, the pigment dispersant may be dispersed only with the solvent.

4. After dispersing the pigment in a non-aqueous vehicle or the like, a pigment dispersant is added to the resulting dispersion.

The desired effects can be obtained by any of these methods.

Regarding the method for preparing the pigment composition shown in the above item 1, the desired effect can be sufficiently obtained by simply mixing the pigment powder and the powder of the pigment dispersant according to the present invention.
Mechanically mixing with an attritor, super mill, various pulverizers, etc., or adding a solution containing the pigment dispersant according to the present invention to a suspension of pigment with water or an organic solvent, and depositing the pigment dispersant on the pigment surface Alternatively, better results can be obtained by performing a close mixing method such as co-dissolving the organic pigment and the pigment dispersant in a solvent having a strong dissolving power such as sulfuric acid and co-precipitating with a poor solvent such as water. it can.

In the use of a pigment and a pigment dispersant as described in 2 to 4 above, dispersers and high-speed mixers are used as dispersing machines for dispersing a pigment or a pigment dispersant in a non-aqueous vehicle or a solvent, mixing these, and the like. By using a homomixer, a kneader, a roll mill, a sand mill, an attritor, etc., the pigment can be dispersed well.

Therefore, according to the present invention, gravure inks such as lime rosin varnish, polyamide resin varnish or vinyl chloride resin varnish, nitrocellulose lacquer, normal dry or baked paint of amino alkyd resin, acrylic lacquer, amino acryl resin baked paint, urethane resin In non-aqueous vehicles such as paints, it shows good fluidity such as a decrease in dispersion viscosity and a decrease in structural viscosity as compared with the case where pigments are used alone, and prints without problems such as color separation and crystal change. Alternatively, it is possible to obtain a beautiful product having good gloss of the coating film.

In particular, the pigment dispersant according to the present invention has an extremely excellent dispersing effect not only in oil-modified amino alkyd resin coatings but also in oil-free alkyd resin coatings.

In addition, the use of the pigment dispersant according to the present invention is not limited to the drainage vehicle, but may include other printing inks, paints, and the like.
Furthermore, even in the coloring of plastics, a colorant having excellent dispersing effect and coloring power can be obtained.

Hereinafter, production examples of the pigment dispersant according to the present invention will be described. In the following, "parts" means "parts by weight", and the numbers of the pigment dispersants in the production examples correspond to the abbreviations of the pigment dispersants shown in Table 1.

[Production Example 1] The compound represented by the formula (IV) was chlorosulfonated by a conventional method, and 50 parts of the obtained compound were dispersed in 900 parts of water. Next, 167 parts of N, N-diethylaminopropylamine was added, the temperature was raised to 60 ° C., and the mixture was stirred at the same temperature for 2 hours. The precipitate is filtered, washed with water and dried at 70 ° C. to obtain a pigment dispersant (1) 6
0 parts were obtained.

[Production Example 2] The compound represented by the formula (IV) was converted into di (chloroacetamidomethyl) by a conventional method, and 50 parts of the obtained compound was treated with 900 parts of water.
Parts. Subsequently, 77 parts of N-aminopropyl-2-pipecholine was added, the temperature was raised to 90 ° C., and the mixture was stirred at the same temperature for 4 hours. The precipitate was filtered, washed with water and dried at 70 ° C. to obtain 68 parts of a pigment dispersant (5).

[Production Example 3] The compound represented by the formula (IV) was chloromethylated by a conventional method, and 50 parts of the obtained compound was dispersed in a mixed solvent consisting of 700 parts of water and 100 parts of methanol. Then, dibutylamine
47 parts were added, the temperature was raised to 70 ° C., and the mixture was stirred at the same temperature for 2 hours. The precipitate was filtered, washed with water and dried at 70 ° C. to obtain 59 parts of a pigment dispersant (8).

[Production Example 4] Potassium-tert-butoxide in a nitrogen atmosphere
77 parts and 198 parts of the compound represented by the formula (VI) were added to 330 parts of anhydrous tert-amyl alcohol, and the temperature was raised to 85 ° C. Then,
50 parts of dimethyl succinate was gradually added over 2 hours, and the mixture was further stirred at the same temperature for 1 hour. After cooling to 40 ° C., 200 parts of methanol was added, and the mixture was stirred for 15 minutes. The precipitate was filtered, washed with methanol and water, and dried at 70 ° C. to obtain 147 parts of a pigment dispersant (4).

The pigment dispersant according to the present invention can be produced by the same method as in Production Examples 1 to 4. Some examples are shown in Table 1.

In order to evaluate the effect of the pigment dispersant according to the present invention,
A paint having the following composition was prepared.

Formulation (1) Pigment 9.5 parts Pigment dispersant 0.5 part Alkyd resin-based varnish (non-volatile content 60%) 26.4 parts Melamine resin-based varnish (non-volatile content 50%) 13.6 parts Thinner 20 parts (xylene / n-butanol = 8/2) 48.3 parts of mixed varnish added after dispersion (alkyd / melamine = 7/3 (solid content)) Formulation (2) Pigment 9.5 parts Pigment dispersant 0.5 part Oil-free polyester resin varnish 26.4 parts (nonvolatile content 60%) Melamine resin Varnish (non-volatile content 50%) 13.6 parts Swazole 20 parts Mixed varnish added after dispersion 48.3 parts (alkyd / melamine = 7/3 (solid content)) Put the above mixture in a container, add steel ball and paint Dispersed with a shaker to make paint. These paints were compared with a paint without a pigment dispersant (a paint in which no pigment dispersant was added in the above formulation and the pigment was 10 parts) according to the following evaluation method. Table 2 shows examples of the results. The numbers of the pigment dispersants in Table 2 correspond to the abbreviations shown in Table 1.

Evaluation method (1) The viscosity of the obtained paint was measured by a B-type viscometer and determined (measuring temperature 25 ° C.). The evaluation was made by a relative comparison with the paint without the pigment dispersant added, and the one having a low viscosity was regarded as good.

：: good △: somewhat good ×: poor Evaluation method (2)
It was adjusted with a thinner so that it would be seconds, sprayed on a tin plate with an air spray gun, baked, and visually evaluated and measured with a gloss meter at 20 ° gloss to make a comprehensive evaluation of the sharpness of the painted surface.

○: Excellent △: Good ×: Poor These paints showed almost no increase in viscosity when they were left for one week and the viscosity was measured with the same viscometer. In addition, a 1 / 10-cut light-colored paint was prepared using a white paint adjusted with titanium white, the viscosity was adjusted to 23 seconds with a Ford cup 4, and placed in a test tube to observe the aggregation state. No separation or sedimentation was observed.

Further, the pigment to which the pigment dispersant according to the present invention was added showed good dispersibility without causing aggregation even in nitros cellulosic lacquer, acrylic resin paint and gravure ink.

Claims (2)

(57) [Claims] 1. A pigment dispersant represented by the formula (1). Equation (1) Represents R _{1 to} R ₁₀ represent a hydrogen atom. p represents an integer of 1 to 3. X: directly bonded or -SO ₂ NH-, -CONH-, -CH ₂
NHCOCH ₂ NH—, —CH ₂ NH—. R ₁₁ , R ₁₂ : each independently, a saturated or unsaturated alkyl group or R ₁₁ , R ₁₂ or a single nitrogen atom or containing the nitrogen atom and an oxygen atom, may be substituted with an alkyl group or a hydroxyl group It represents a good 5- or 6-membered ring. n represents an integer of 1 to 3. _{Z: -SO 2 -, - CH} 2 representing the NHCOCH ₂ NH-. R _{13 to} R ₁₆ represent a hydrogen atom. R ₁₇ represents an alkyl group. 2. A pigment composition comprising a pigment and the pigment dispersant according to claim 1.