JPS621426B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a pigment ink that uses an organic pigment as a colorant, and its purpose is to have excellent dispersibility of the pigment, and when writing on paper, the handwriting has excellent fixation properties. , it is an object of the present invention to provide a pigment ink that can be coated with inks of different colors after drying (hereinafter referred to as "multicolor"). Conventionally, pigment inks have been made by dispersing pigments in a solution containing protective colloidal resins, which are various natural and synthetic water-soluble polymeric substances. However, if the amount of protective colloidal resin used is increased,
Although an ink with relatively excellent dispersion stability can be obtained,
When a water-soluble polymer is in an aqueous solution, its molecular chain is elongated, and this tendency is particularly pronounced for polyelectrolytes such as sodium alginate and sodium polyacrylate.As a result, the viscosity of the ink increases, and the ink becomes ink on writing utensils. When filling and writing, ink flow becomes poor, so the amount of protective colloidal resin used must be reduced, which inevitably results in poor dispersion stability and, furthermore, poor handwriting fixation. There was a question of sufficiency. As described above, in conventional inks, contradictory ink properties such as dispersion stability and ink flowability related to viscosity are influenced by the amount of protective colloidal resin used, so it has been difficult to obtain fully satisfactory inks. . Also, for example, if the color is overlaid, the overcolored area will bleed,
The ink spread and did not fully satisfy the heavy color property. Therefore, the present inventors have developed the present invention as a result of intensive research based on the viewpoint that dispersion stability, ink flowability, and heavy color property cannot be fully satisfied by using a water-soluble resin. The gist of the completed product is a pigment ink in which an organic pigment is dispersed, and the ink composition contains an emulsion of a water-insoluble synthetic resin in an amount of 2 to 18% by weight in terms of solid content. What is particularly important in the present invention is the use of an emulsion of a water-insoluble synthetic resin,
As a result, the polymer chains become spherical and dispersed in water, making it possible to lower the viscosity of the ink while improving dispersion stability and handwriting fixation. Since the water-insoluble resin forms a film, the inks will not mix directly with each other, and the heavy colored areas will not be smeared due to bleeding or spreading of the ink. The synthetic resin emulsion of the present invention includes general emulsions and microemulsions such as polyacrylic ester emulsion, polymethacrylic ester emulsion, acrylic copolymer emulsion, and synthetic fatty acid vinyl ester-vinyl acetate copolymer emulsion. The amount used is 2 to 18% by weight, more preferably 4 to 9% by weight, and 2% by weight based on the total ink.
Below 18% by weight, the handwriting is not sufficiently fixed.
Above that, the viscosity becomes high and no favorable results can be obtained. Furthermore, any type of organic pigment can be used as the organic pigment, but specific examples include:
CI Pigment Yellow 1, 2, 3, 5, 5
12, 13, 14, 15, 83, CI Butt Yellow 1, CI Pigment Orange 1, 5, 13, Same
16, 17, 24, CI Butt Orange 3, CI Pigment Red 1, 2, 3, 4, 5, 7, 9, 12, 22, 23, 37, 38, 48
Calcium Lake, 48 Barium Lake, 48 Manganese Lake, 49 Barium Lake, 50, Same
51, 53 barium lake, 57 calcium lake, 63 calcium lake, 63 manganese lake, 81, 83 aluminum, 88, 112,
214, CI Pigment Violet 1, 2, 3, 23, CI Pigment Blue 1, 2,
15, 16, 17, CI Vat Blue 4, CI Pigment Green 2, 7, 8, 10, CI Pigment Brown 1, 2, 5, CI Vat Brown 3, CI Pigment Black 1, etc.
Organic pigments indicated by (color index),
Colaneal Red FGR, Colaneal Blue AR,
Colaneal Yellow 10G-30, Colaneal Red
4RH-30, Colaneal Green GG, Colaneal Yellow FGL-30, Colaneal Yellow HR, Colaneal Orange GR-30, Impelon Blue KB, Impelon Green KG, Impelon Yellow KR, Impelon Green GG, Impelon violet
KB, Impelon Orange KR (manufactured by Hoechst), Ryudai-W Scarlet F-3G, Ryudai-W Red FBI, Ryudai-W Blue
RLCH, Ryudai-W Green FBT, Ryudai-W Yellow FF8G, Ryudai-W Yellow Brown N, Ryudai-W Orange GRK, Ryudai-W Violet FFBN (manufactured by Dainippon Ink & Chemicals Co., Ltd.), EM Red G, EM Red B,
EM Scarlet 2Y, EM Blue NCB, EM Blue 2G-10, EM Green G, EM Orange O, EM
Yellow FG, EM Yellow G, EM Yellow GR, EM Yellow 2RN, WS Scarlet 2YD-1, WS Blue
ES-1, WS Yellow 2RN-1 (manufactured by Toyo Ink Manufacturing Co., Ltd.), Polx Thread RM-Y, Polx Blue PM-B, Polx Green PM-
Organic pigments such as 2B, Portx Yellow PM-10GC (manufactured by Sumika Color), Fuji SP Red #73, Fuji SP Blue #41, Fuji SP Green #7005, Fuji SP Orange #92 (manufactured by Fuji Color Co., Ltd.) Aqueous dispersion-processed organic pigments treated with surfactants, etc.
Hydracol DNA Orange, Hydracol Hansa Yellow GSX, Hydracol Alpha Blue,
Hydracol Phthalocyanine Green (manufactured by Hercules), Sanogran Red BN, Sanogran Yellow 4G, Sanogran Green 3GLS, Sanogran Blue 2GLS, Sanogran Violet BL,
There are powder processed pigments such as Sanogran Black 5BL (manufactured by Sandoz), and these can be used alone or in combination.
It can be used as a mixture of more than one species, and the amount used is preferably 2 to 25% in terms of pure pigment. Furthermore, the ink solvent is mainly water, and in addition, polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, glycerin, and thiodiethylene glycol, ethylene glycol monoalkyl ethers such as methyl cellosolve and ethyl cellosolve, methyl carbitol, and ethyl. Diethylene glycol monoalkyl ether such as carbitol and lower alcohols such as ethanol, propanol, and butanol are used alone or in combination.
The appropriate amount to be used is 2 to 20% by weight based on the total ink. In addition to the above, film forming agents such as butyl cellosolve acetate and butyl carbitol acetate, preservatives, dispersants, antifungal agents, and PH
Conditioners, antifoaming agents, etc. can also be used. Particularly, favorable results can be obtained by using a dispersant, and such dispersants include alkali metal salts such as styrene-maleic anhydride copolymers, styrene-acrylic acid copolymers, ammonium salts, Amine salts and other surfactants are effective;
When used, 0.5 to 5% by weight based on the total ink
used. Methods for preparing ink using the above-mentioned composition include ball mills, roll mills, sand mills, vibration mills, Chemistler, homomixer, or ultrasonic dispersion methods, which are generally used for pigment dispersion, and pigments and other materials used. The pigment may be selected by considering the following factors, and the pigment may be dispersed in the liquid. Hereinafter, the present invention will be explained with reference to Examples. In Examples and Comparative Examples, "parts" represent "parts by weight." Example 1 Colanyl Blue AR (manufactured by Hoechst, pigment content 40%)...22.5 parts Primal AC-61 (manufactured by Nippon Acrylic Co., Ltd., polyacrylic acid ester emulsion content 46%)
…18.0 parts Ethylene glycol …6.5〃 Butyl cellosolve …1.4〃 Demol N (manufactured by Kao Atlas Co., Ltd., sodium naphthalene sulfonic acid formalin condensate) …1.8 parts Pentachlorophenol sodium salt (preservative) …0.2〃 Water …49.6〃 Above Place the formulation in a 200ml glass beaker;
A blue ink was obtained by stirring with a magnetic stirrer for 1 hour. Comparative Example 1 In Example 1, Aron A-20LL, which is a water-soluble acrylic resin, was used instead of Brimal AC-61.
(Manufactured by Toagosei Co., Ltd., containing sodium polyacrylate 20
%) 25 parts were used to obtain an ink in the same manner. Example 2 Colanil Yellow FGL-30 (manufactured by Hoechst, containing 40% pigment) ...20 parts Cevian A-4715 (manufactured by Daicel Corporation, containing 50% polyacrylic acid ester emulsion) ...8.0〃 Ethylene glycol ...4.6〃 Texanol…0.3 parts Butyl carbitol acetate…0.6〃 Lunox 1500A (manufactured by Toho Chemical Co., Ltd., anionic surfactant) …3.4〃 Nonal 310 (manufactured by Toho Chemical Co., Ltd., nonionic surfactant) …1.0〃 Broxel CRL ( Manufactured by ICI, preservative) ...0.02〃 Water ...62.08〃 In the above formulation, Carbon Black MA100, Lunox 1500A, ethylene glycol and water are thoroughly kneaded and dispersed using a triple roll, then mixed with the rest of the composition and stirred. A yellow ink was obtained. Comparative Example 2 In Example 2, a water-soluble polymer, Isoban (manufactured by Kuraray Co., Ltd.,
Isobutylene-maleic acid copolymer-NH ₄ salt) 4
An ink was obtained in the same manner. The properties of the inks obtained in the above Examples and Comparative Examples are as shown in the following table.

【table】

[Table] As described above, the pigment ink of the present invention is an ink with excellent dispersion stability, fixing property, and heavy color property, and is suitable for writing instruments, taking into account the particle size, viscosity, and surface tension of the pigment. Then, for printing, for recorder,
It is also suitable as an ink for stamps.

Claims (1)

[Claims] 1. A pigment ink containing an organic pigment dispersed therein, containing 2 to 18% by weight of a water-insoluble synthetic resin emulsion in terms of solid content in the ink composition.