JP2510011C - - Google Patents

Description

The present invention relates to a surface-treated monoazo lake pigment useful in various applications, particularly as a pigment for printing inks, and more specifically, to increase the ink surface tension. The present invention also relates to a monoazo lake pigment for improving ink fluidity, a method for producing the same, and a printing ink composition obtained using the same. (Prior Art) Conventionally, monoazo lake pigments obtained by coupling an aromatic amine having a soluble group as a diazo component and coupling betaoxynaphthoic acid, betatanphthol, and the like as a coupler component are used for coloring printing inks, paints, plastics, and the like. Widely used for various applications. These mono azo lake pigments, to make the color transparent and sharp,
Rosin treatment is also performed to improve dispersibility. In this rosin treatment, a rosin alkali salt solution (rosin soap) is usually added to a coupler component or a dye, and then a lake metal salt such as calcium chloride is added to precipitate on the pigment surface as an insoluble rosin lake metal salt. Things. The rosin-treated pigment obtained by the above-mentioned conventional method improves the sharpness and dispersibility of the pigment.However, when used in offset printing inks, there is a decrease in flowability and a decrease in printability such as a decrease in surface tension of the ink. there were. (Problems to be Solved by the Invention) Therefore, in the present invention, in a monoazo lake pigment obtained by coupling an aromatic amine having a soluble group as a diazo component and coupling a betaoxynaphthoic acid, a betanaphthol or the like as a coupler component, It is an object of the present invention to provide a rosin-treated pigment which does not adversely affect printability without impairing improvement in printability, sharpness, dispersibility, and the like, and a method for producing the same. [Constitution of the Invention] (Means for Solving the Problems) That is, the present invention provides a diazo component obtained by diazotizing an aromatic amine having a soluble group, and a coupler component selected from betanaphthols and betaoxynaphthoic acids. In a solution of the dye obtained by coupling the dye in the presence of a rosin alkali metal salt, and then adding an acid to a system containing the obtained pigment and a rosin alkali metal salt or a rosin lake metal salt. A method for producing a monoazo lake pigment surface-treated with free rosin obtained by adjusting the pH to 5 to 3, a surface-treated monoazo lake pigment obtained by the above-mentioned production method, and the surface-treated monoazo lake pigment and a printing ink vehicle. Including printing ink compositions. The aromatic amine having a soluble group used in the present invention includes, for example, 1
-Amino-4-methylbenzene-2-sulfonic acid (common name p-toluidine-m-
Sulfonic acid), 1-amino-4-methyl-5-chlorobenzene-2-sulfonic acid, 1-amino-4-chloro-5-methylbenzene-2-sulfonic acid, 1-amino-4-methylbenzene-3 -Sulfonic acid, 1-amino-3-methyl-4-sulfonic acid and the like. Representative examples of the coupler component include betaoxynaphthoic acid and betanaphthol, and other oxynaphthoic acids, such as a lower alkyl group, an alkoxy group, and a betaoxynaphthoic acid substituted with a halogen atom. You may. In addition, a coupler component other than betaoxynaphthoic acid can also be partially used for betaoxynaphthoic acid. The monoazo lake pigment of the present invention using the above raw materials can be produced according to a conventionally known method for producing a monoazo lake pigment. That is, an aromatic amine having a soluble group is diazotized according to a conventional method, while the above-mentioned coupler component is prepared according to a conventional method to prepare a base solution, and both are coupled according to a conventional method. P of the system at this time
H is made to be alkaline of 7.5 to 12.5. After coupling, a lake is formed by adding a lake agent (metal salt) to the dye solution. Examples of the lake metal include calcium, barium, strontium, and manganese. Rosin in the present invention means natural rosin acid (tall oil rosin acid, gum rosin acid, wood rosin acid, etc.), modified rosin acid (hydrogenated rosin acid, disproportionated rosin acid, polymerized rosin acid, fumarated rosin acid, maleated The rosin alkali metal salt solution of the present invention is an aqueous solution of rosin sodium salt, rosin potassium salt, etc. The rosin alkali metal salt aqueous solution is prepared in advance in the coupler component. Or a dye solution, and then a laker is added to form a lake. In this case, the water-soluble rosin alkali metal salt is replaced with the laked metal salt to make it insoluble, and the pigment surface becomes insoluble. The amount of the rosin alkali metal salt solution to be added is 3 to 30% by weight as a resin acid solid content based on the dye pigment. The surface-treated monoazo lake pigment of the present invention is prepared by adding an acid to a system containing the pigment obtained above and a pigment coated with a rosin alkali metal salt or a rosin lake metal salt to adjust the pH to 5 to 3. Acids that can be used include mineral acids such as hydrochloric acid and organic acids such as acetic acid, etc. In the present invention, a press cake obtained by heating, filtering and purifying a pigment slurry obtained by a conventional method is used. Similar results can be obtained by reslurrying the system to make the pH of the system about 3. In this case, the treatment is preferably performed at 40 ° C. or lower to prevent crystal growth of the pigment. As the vehicle, for example, in the case of offset ink, 20 to 50 parts by weight of a resin such as a rosin-modified phenol resin, a petroleum resin, an alkyd resin, or a dry oil-modified resin. Arni oil, tung oil, such as soybean oil vegetable oil 0-30
Parts by weight, 10 to 60 parts by weight of a solvent such as n-paraffin, isoparaffin, aromatech, naphthene, α-olefin and the like. The monoazo lake pigment of the present invention is blended with the vehicle for offset ink, and other known additives such as an ink solvent, a dryer, a leveling improver, and a thickener are appropriately blended to obtain a printing ink composition. Also, as gravure ink, gum rosin, wood rosin, tall oil rosin, calcified rosin, lime rosin, rosin ester, maleic resin, Gilsonite, dammar, shellac, polyamide resin, vinyl resin, nitrocellulose, cyclized rubber, chlorinated rubber, Ethyl cellulose, cellulose acetate, ethylene-vinyl acetate copolymer resin, urethane resin, polyester resin, 10 to 50 parts by weight of a resin mixture such as alkyd resin, n-hexane, toluene, ethanol, methanol, acetone, ethyl acetate, ethyl lactate, 30 to 80 parts by weight of a solvent such as cellosolve, diacetone alcohol, chlorobenzol, ethyl ether, acetal ethyl ether, ethyl acetoacetate, butyl acetate cellosolve; 3 to 35 parts by weight of the monoazo lake pigment of the present invention; Um, barium carbonate, calcium carbonate, gypsum, alumina white, clay, silica, silica white, talc, calcium silicate, precipitating pigments such as 0 to 20 parts by weight of magnesium carbonate, and other auxiliary agents, as a plasticizer, It appropriately contains an ultraviolet inhibitor, an antioxidant, an antistatic agent and the like. Hereinafter, examples will be described. In the examples, "part" represents "part by weight" and "%" represents "% by weight". EXAMPLES Example 1 18.7 parts of p-toluidine-m-sulfonic acid are dissolved in a solution consisting of 300 parts of water and 4 parts of sodium hydroxide. After adding 25 parts of 35% hydrochloric acid and performing acid precipitation, 200 parts of ice are added, and the mixture is cooled to 0 ° C. 7 parts of sodium sulfite dissolved in 25 parts of water was added, and the mixture was stirred at 5 ° C. or lower for 30 minutes to obtain a diazo component. On the other hand, 18.7 parts of betaoxynaphthoic acid were mixed with 1500 parts of water and 1 part of sodium hydroxide.
A component dissolved in one part of the solution and cooled to 15 ° C. is used as a coupler component.
A diazo component is added dropwise to the coupler component in 20 minutes, and a coupling reaction is performed. 3
After stirring for 0 minutes, 64 parts of 10% rosin soap (15% as resin solid content with respect to pigment content)
%) And adjust the pH to 12.3 with a 1% aqueous sodium hydroxide solution. next,
58 parts of 35% calcium chloride aqueous solution is added and stirred for 2 hours to complete the lake formation reaction. After heating to 70 ° C, the mixture is filtered and washed with water, and the obtained press cake is reslurried in 2000 parts of water. 5% hydrochloric acid is added dropwise to the slurry to adjust the pH to 3.0. The mixture was stirred at room temperature for 1 hour, filtered, washed with water, dried and pulverized to obtain 49 parts of a monoazo lake pigment. For comparison, a pigment without the acid treatment (a conventional pigment) was also synthesized. The contact angles of the pigment obtained in this example and the pigment obtained by the conventional method were compared. With respect to water, the pigment obtained by the conventional method was 41 °, and the pigment obtained in this example was 49 °. For methylene iodide, the pigment obtained by the conventional method was 23 °, the pigment obtained in the present example was 19 °, and the pigment obtained in the present example was It was hydrophobic and lipophilic compared to the pigment. When the heat of wetting with water was measured with a calorimeter, the pigment according to the conventional method became 5.1 cal / g, whereas the pigment according to the present example became hydrophobic at 3.0 cal / g. The pigment obtained above was converted into an ink and tested. The varnish used was 50 parts of Tamanol 361 (manufactured by Arakawa Chemical: rosin-modified phenolic resin) and 20 parts of linseed oil.
And 30 parts of No. 5 solvent (Nippon Oil Co., Ltd .: ink solvent) at 200 ° C.
And dissolved by heating. Next, gel varnish was prepared by adding 98 parts of this varnish to 2 parts of aluminum octylate. 70 parts of the obtained gel varnish, 20 parts of the above pigment, and 10 parts of No. 1 solvent (Nippon Oil Co., Ltd .: ink solvent) were blended and mixed and kneaded with a three-roll mill to obtain an offset ink. No difference was observed between the pigment obtained in this example and the pigment obtained in the conventional example in dispersibility, hue, transparency, sharpness, etc., but the pigment of this example was compared with the pigment of the conventional method. As a result, the fluidity was good and no thickening (tightness) with time was observed. When the pigment according to this example and the conventional method were subjected to extraction treatment with methanol and the infrared absorption spectrum of the extract was measured, the pigment according to the conventional method showed absorption at around 1540 cm ^-1 due to the metal carboxylate, In the pigment according to this example, the above absorption disappeared, and a new absorption due to free carboxylic acid appeared around 1700 cm ^-1 . Example 2 18.5 parts of p-toluidine-m-sulfonic acid and 4-methyl-aniline-3
0.2 parts of sulfonic acid are diazotized in a conventional manner, and 58 parts of a 35% aqueous solution of calcium chloride are added to obtain a diazo solution. On the other hand, 18.7 parts of betaoxynaphthoic acid is dissolved according to a conventional method, and 106 parts of 10% rosin soap (25% as a resin solid content with respect to a coloring matter) is added to obtain a coupler liquid. Example 1 Coupling reaction by dropping a diazo solution over 20 minutes into a coupler solution
A lake formation reaction is carried out in the same manner as described above. The pH at the end of the lake formation was 12.0. After stirring for 1 hour, 5% hydrochloric acid is added dropwise to adjust the pH to 3.0. Stir for 1 hour,
After filtration, washing with water, drying and pulverization, 53 parts of an azo-luke pigment were obtained. For comparison, a pigment without the acid treatment (a conventional pigment) was also synthesized. The offset ink prepared from the pigment of the present example has less emulsification fluctuation (fluidity fluctuation when water is forcibly emulsified into the ink) compared to the pigment obtained by the conventional method, and the apparent surface of the ink. An increase in the tension and an increase in the surface tension of the emulsion were observed. [Effect of the Invention] The surface-treated monoazo lake pigment obtained in the present invention is
Lipophilicity is increasing. Therefore, the printing ink using the surface-treated monoazo lake pigment of the present invention has a high fluidity, a small fluctuation in the fluidity when water is forcibly emulsified in the ink, and increases the apparent surface tension of the ink. Moreover, the surface-treated monoazo lake pigment of the present invention shows no difference in pigment dispersibility, transparency, sharpness, and hue from those obtained by the conventional method. As described above, the surface-treated pigment according to the present invention has a surface characteristic different from that of the conventional rosin-treated pigment, and in addition to pigments for printing inks such as offset printing inks and gravure printing inks, for paints and plastics. Excellent as a colorant.

Claims (1)

[Claims] 1. In a solution of a dye obtained by coupling a diazo component obtained by diazotizing an aromatic amine having a soluble group and a coupler component selected from betanaphthols and betaoxynaphthoic acids, a rosin alkali metal salt Monoazo lake pigment surface-treated with a free rosin obtained by adding an acid to a system containing the obtained pigment and a rosin alkali metal salt or a rosin lake metal salt after the lake formation in the presence of Manufacturing method. 2. A surface-treated monoazo lake pigment obtained by the production method according to claim 1. 3. A printing ink composition comprising the surface-treated monoazo lake pigment according to claim 2 and a vehicle for a printing ink.