JPH0826246B2 - Novel crystalline monoazo lake pigment and printing ink composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a monoazo lake pigment used in various applications, particularly in printing inks, paints, plastics, stationery and the like.

(Prior Art) Conventionally, a monoazo lake pigment composed of an aromatic amine having a soluble group and β-naphthol or β-oxynaphthoic acid has been used for coloring printing inks, paints, plastics, stationery and the like. For example, Pigment Red 48: 1 is 1
-Amino-4-methyl-5-chlorobenzene-2-sulfonic acid sodium salt (Na 2B) was used as the diazo component, and β-oxynaphthoic acid was used as the coupler component. The obtained monoazo dye was heated to 75-85 ° C and chlorinated. It is obtained by braking with barium.

Water-based gravure ink is often printed on corrugated board, and pigments are required to have high hiding power and high tinting strength.

Conventionally, a method of growing primary particles or adding an inorganic pigment such as titanium oxide has been known as a means for improving the hidden pay power, but these methods have a drawback that the coloring power is lowered. Was there.

As described above, the coloring power of the hidden pay power is considered to be a contradictory property, and the appearance of a pigment having a high hidden pay power and a high coloring power has been desired.

A mixed coupling rake method for making particles fine is widely known as a means for achieving high coloring power. For example, 2-aminonaphthalene-1,5-sulfonic acid (D acid)
Pigment which was added with 0.1-5.0 mol% to Na-B acid, diazotized, and mixed and coupled with β-oxynaphthoic acid was
Since the particles are fine, the coloring power is high, but it becomes transparent,
Hidden pay power is greatly reduced.

The crystal form of this pigment has a diffraction angle (2
θ ± 0.2 °, Cu-Kα) 4.6 °, 24.8 ° with strong diffraction intensity, 14.1 °, 18.0 °, 24.0 °, 17,4 ° with medium diffraction intensity, 8.4 °, 10.4 ° It has a relatively weak diffraction intensity at 20.4 °, 21.6 ° and 27.4 ° (hereinafter referred to as A type).

(Problems to be Solved by the Invention) As a result of studying a lake formation method for a monoazo dye obtained by mixed coupling of Na 2B acid and D acid, the present inventors have found that By subjecting the dye to heat treatment at high temperature for a long time or solvent treatment and then lake formation, a pigment showing a new crystal form (hereinafter referred to as B type) having an X-ray diffraction pattern different from that of the A type crystal form pigment is obtained, This B
It was found that the type crystal form is a pigment that is superior to the A type crystal form in both hiding power and coloring power, and also in sharpness, gloss, and light resistance.

[Structure of Invention]

(Means for Solving the Problems) The present invention provides 2B acid Na of 95 to 99.9 mol% and D acid of 0.1 to 5 mol%.
A monoazo lake pigment obtained by mixed coupling lake with and as a diazo component and β-oxynaphthoic acid as a coupler component. The X-ray diffraction angle (2θ ± 0.2 °; Cu
-Kα) strong diffraction intensity at 4.6 °, medium diffraction intensity at 23.9 °, 25.7 °, 14.0 °, 15.1 °, 17.8 °, 19.4 °
This is a source for the above-mentioned monoazo lake pigment, which has a relatively weak diffraction intensity at 2 ° and 20.5 °.

The monoazo lake pigment of the present invention comprises 2B acid Na 95 to 99.9 mol%.
And a D acid of 0.1 to 5 mol% as a diazo component and β-oxynaphthoic acid as a coupler component are mixed and coupled to obtain a monoazo dye having a pH of 7.5 to 12.5, preferably 8.0.
To 8.5 to 75 to 100 ℃, preferably 85 to 90 ℃, 0.5
It can be obtained by holding for 5 to 5 hours, preferably 1.5 to 3 hours, or after emulsion treatment with an aromatic solvent, dropping an aqueous barium salt solution to form a lake. Examples of barium salts for rake include barium chloride, barium nitrate, and barium acetate.

As the vehicle for the printing ink of the present invention, for example, in the case of offset ink, rosin-modified phenolic resin, petroleum resin, alkyd resin, or 20 to 50 parts by weight of resin such as drying oil-modified resin, linseed oil, tung oil, soybean oil 0 to 30 parts by weight of vegetable oil such as n-paraffin, isoparaffin, aromatech, naphthene, solvent such as α-olefin 10 to 60
It consists of parts by weight. This offset ink vehicle is mixed with the monoazo lake pigment of the present invention, and other known additives such as an ink solvent, a drier, a leveling improver and a thickener are appropriately mixed to obtain a printing ink composition. Also,
As gravure ink, gum rosin, wood rosin,
Tall oil rosin, calcified rosin, lime rosin, styrene acrylic resin, styrene maleic acid resin, rosin ester, maleic acid resin, Gilsonite, Dalman, shellac, polyamide resin, vinyl resin, nitrocellulose, cyclized rubber, chlorinated rubber, ethyl cellulose , Cellulose acetate, ethylene-vinyl acetate copolymer resin, urethane resin, polyester resin, alkyd resin, etc., 10 to 50 parts by weight, n-hexane, toluene, ethanol,
Solvents such as methanol, acetone, ethyl acetate, ethyl lactate, ethyl lactate, cellosolve, diacetone alcohol, chlorobenzol, ethyl ether, acetal ethyl ether, ethyl acetoacetate, butyl cellosolve, water 30-80 parts by weight, monoazo lake pigment 3 of the present invention 35 parts by weight, 0 to 20 parts by weight of extender pigments such as barium sulfate, barium carbonate, calcium carbonate, gypsum, white alumina, clay, silica, silica white, calcium silicate, and precipitated magnesium carbonate. It appropriately contains a plasticizer, an ultraviolet ray inhibitor, an antioxidant, an antistatic agent, and the like.

(Effect of the Invention) The monoazo lake pigment of the present invention is a pigment of B type crystal form, unlike the A type crystal form which is the X-ray diffraction pattern of conventional Pigment Red 48: 1.

The B-type crystal pigment obtained in the present invention exhibits excellent hidden paying power and coloring power when used in printing ink, paint, etc.
It is also excellent in sharpness, gloss and light resistance.

(Examples) Hereinafter, the present invention will be described with reference to Examples. In the examples, "part" means "part by weight" and "%" means "% by weight".

Example 1 1-Amino-4-methyl-5-chlorobenzene-2-
96.9 parts of sulfonic acid and 3.6 parts of 2-aminonaphthalene-1,5-sulfonic acid are completely dissolved by stirring in 800 parts of water at 80 ° C for 30 minutes. After adding 93.3 parts of 35% hydrochloric acid to oxidize, allow to cool to room temperature. After cooling, add 800 parts of water and cool to 0 ° C to 3 ° C. Add sodium sulfite dissolved in 100 parts of water and
What was stirred for 0 minutes is used as the diazo component.

On the other hand, a coupler component is prepared by dissolving 76 parts of β-oxynaphthoic acid together with 1400 parts of water, 34 parts of sodium hydroxide and 10.2 parts of sodium carbonate at 15 ° C.

The diazo component was added dropwise to this coupler component over 30 minutes, and stirring was continued for 1 hour to complete the coupling reaction. The pH after coupling was 10.0. Dilute hydrochloric acid was gradually added dropwise to obtain a monoazo dye having a pH of 8.5. This monoazo dye was heated to 85 ° C. over 30 minutes and kept at the same temperature for 2 hours, and then a solution prepared by dissolving 100 parts of barium chloride hydrate in 500 parts of water was added. The mixture was further stirred at 85 ° C for 30 minutes, after the completion of the lake reaction, filtered, washed with water and dried at 85 ° C to obtain 218 parts of a red monoazo lake pigment powder. This pigment has a diffraction angle (2θ ± 0.2 °, Cu-K in the X-ray diffraction pattern as shown in FIG.
α) Diffraction intensity was shown at 4.6 °, 14.0 °, 15.1 °, 17.8 °, 19.4 ° and 20.5 °.

Comparative Example 1 The monoazo dye obtained by carrying out the coupling reaction in the same manner as in Example 1 was heated to 85 ° C. over 30 minutes, and immediately a solution of 100 parts of barium chloride hydrate dissolved in 500 parts of water was added. . After further stirring at 85 ° C. for 30 minutes and completing the lake reaction, Example 1
218 parts of red monoazo lake pigment powder were obtained in the same manner as in.

This pigment is 4.6 in X-ray diffraction as shown in FIG.
°, 8.4 °, 10.4 °, 14.1 °, 18.0 °, 20.4 °, 21.6 °, 24.0
The diffraction intensity was corrected to °, 24.8 ° and 27.4 °.

Test Example 1 (Aqueous Gravure Test) The pigments obtained in Example 1 and Comparative Example 1 were made into an aqueous gravure ink and tested as a pigment composition. 9 parts of the pigment obtained in Example 1 and Comparative Example 1, 49.7 parts of styrene acrylic acid-based varnish, and 150 parts of glass beads were placed in a 225 ml mayonnaise bottle and dispersed for 90 minutes with a paint conditioner, and then 34.6 parts of an additional varnish was added, The mixture was dispersed for 10 minutes with a paint conditioner, and the glass beads were filtered off to obtain a red aqueous gravure dark ink.

Also, 5 parts of the dark color ink and 30 parts of the white ink for aqueous gravure were well stirred in a paper cup to obtain a light color ink. The dark ink was spread on Manila board paper with a # 3 bar coater, and the gloss (60 °) was measured with a gloss meter. Further, the color was spread on a black background art paper with a # 6 bar coater, and the hidden paying power was measured by a color machine L ^* value. The larger the L ^* value, the greater the hidden pay power.

The light-colored ink was developed on a white liner paper with a # 6 bar coater, and the coloring power was measured by a color machine L ^* value. The smaller the L ^* value, the higher the coloring power.

 The results are shown in Table-1.

The water gravure ink using the pigment of Example 1 has a high gloss,
The hidden pay power was high and the concentration was high.

Test Example 2 (Offset Test) The pigments obtained in Example 1 and Comparative Example 1 were made into offset inks and tested as a pigment composition.

The varnish used was 50 parts of Tamanol 361 (Arakawa Chemical Co., Ltd .: rosin-modified phenolic resin), 20 parts of linseed oil, and 30 parts of No. 5 solvent (Nippon Oil Co., Ltd .: ink solvent).
It was heated and melted at 00 ° C to manufacture. Then, 2 parts of aluminum octylate was added to 98 parts of this varnish to form a gel varnish.

70 parts of the obtained gel varnish and 20 parts of the red pigment of the present invention obtained by using the pigment obtained in Example 1 and Comparative Example 1 and 10 parts of No. 1 solvent (Nippon Oil Co., Ltd .: ink solvent) were blended, The mixture was kneaded and mixed with a triple roll to obtain an offset ink having a tack value of 9.0 parts.

This was applied to art paper using a small rotary printing machine (RI tester), and the gloss, sharpness (color machine C value), and coloring power (color machine L ^* value) of the obtained color-developed paper were compared. . The larger the C value, the higher the sharpness, and the smaller the L ^* value, the higher the coloring power. The results are shown in Table-2.

Next, the color-developing paper used in Test Example 2 was accelerated in light resistance with a fedometer, and the color machine ΔE values at each acceleration time were compared. The results are shown in Table-3.

 The larger the ΔE value, the larger the color change.

The printed matter using the pigment of Example 1 had good weather resistance.

[Brief description of drawings]

FIG. 1 shows X of the monoazo lake pigment obtained in Example 1.
FIG. 2 is a line diffraction diagram, and FIG. 2 is an X-ray analysis diagram of the monoazo lake pigment obtained in Comparative Example 1.

Claims (2)

[Claims] 1. A sodium salt of 1-amino-4-methyl-5-chlorobenzene-2-sulfonate in an amount of 95 to 99.9 mol% and 2-
Aminoazophthalene-1,5-sulfonic acid 0.1 to 5 mol% as a diazo component, β-oxynaphthoic acid as a coupler component is a monoazo lake pigment obtained by mixed coupling lake, X-ray diffraction angle (2θ ± 0.2 °; Cu-K
α) Strong diffraction intensity at 4.6 °, medium diffraction intensity at 23.9 °, 25.7 °, 14.0 °, 15.1 °, 17.8 °, 19.4 °, 20.
The above monoazo lake pigment having a relatively weak diffraction intensity at 5 °. 2. A printing ink composition comprising the monoazo lake pigment according to claim 1 and a printing ink vehicle.