JPS5855993B2 - Yusei Ink Seibutsu - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an oil-based ink composition, more specifically, a low odor and low toxicity aliphatic hydrocarbon solvent and (or one or more alicyclic hydrocarbon solvents), The present invention relates to an oil-based ink composition comprising a salt-forming compound of 2-alkyl 4.5-dihydroimidazole and an acidic dye and a film-forming agent that are soluble in this solvent.

Oil-based ink compositions conventionally used for marking glass, plastic, wood, paper, and other objects generally contain aromatic hydrocarbons such as toluene and xylene as solvents and dyes dissolved in these, i.e., oil-soluble dyes and film-forming solvents. It was widely used because it has good water resistance and sunlight fastness.

However, recently there has been a desire to develop oil-based ink compositions that are less likely to cause pollution problems, that is, are less toxic and have less odor.

Therefore, in order to solve this problem, it is desired to develop an oil-based ink composition that uses a low toxicity and low odor aliphatic hydrocarbon solvent or alicyclic hydrocarbon solvent as a solvent instead of toluene or xylene. It's here.

The most important thing in this oil-based ink composition is the development of a dye that dissolves in the above-mentioned solvents, and by the method described below, a low toxicity and low odor aliphatic hydrocarbon solvent or alicyclic hydrocarbon solvent is used as the solvent. It has been considered to prepare oil-based ink compositions.

However, these inks have the following drawbacks.

That is, (1) Dyes soluble in aliphatic hydrocarbon solvents and alicyclic hydrocarbon solvents can be produced by introducing long-chain alkyl groups into dye molecules, unlike conventional oil-soluble dyes. can.

Although it is possible to attach an alkyl group directly to a dye, generally an intermediate having a long chain alkyl group is first synthesized, and then a dye is synthesized from this.In this case, the alkyl group is particularly an alkyl group having 4 or more carbon atoms, Because it is a cycloalkyl group, it is difficult to synthesize intermediates and dyes, and the resulting dyes are often semisolid.

Difficulties in synthesizing the intermediates and dyes and the fact that they are not general purpose dyes make this type of dye expensive.

Therefore, oil-based ink compositions made of this dye are expensive.

(2) Currently, in order to solubilize oil-soluble dyes that are soluble in aromatic hydrocarbon solvents in aliphatic hydrocarbon solvents or alicyclic hydrocarbon solvents, higher fatty acids such as oleic acid and nonylphenol are used. Oil-based marking ink is obtained by dissolving it in alkylphenol at 80 to 120°C and then diluting it with a solvent. However, since this type of ink contains solubilizers such as oleic acid and nonylphenol, the writing marks do not dry easily and remain sticky forever. It has certain drawbacks.

(3) Inks prepared by making salts from acidic dyes or basic dyes and cationic activators or anionic activators and dissolving the salt-formed dyes use activators; When a handwritten mark is immersed in water, the activator gradually disappears, and the dye also disappears, resulting in a decrease in density.

Furthermore, since the salt-forming dye with the activator is in the form of a sticky paste, the handwritten marks also tend to be sticky.

(4) A type of dye in which the carboxyl group and sulfone group of an acidic dye are each chlorinated and reacted with an amine soluble in an aliphatic hydrocarbon solvent or an alicyclic hydrocarbon solvent to form an acid amide is produced by first converting the carboxyl group and sulfone group into an acid amide. To make acid chloride, it is reacted with thionyl chloride, phosphorus trichloride, and phosphorus pentachloride, but in industrial production, it is necessary to handle the chlorinating agent, extract the reactant, and separate the acid amide, which is the reactant with the amine. Dyes are expensive because it is difficult to

Naturally, oil-based ink compositions made from this type of dye are expensive.

* * (5) When using alkylphenol/novolac resin as part of a basic dye-based solubilizer, other solubilizers must be used in conjunction with it because solubilization is weak when used alone. The problem is that only ink with sticky marks can be obtained.

The present inventors have conducted various studies on means to overcome the above-mentioned drawbacks of ink compositions, and as a result, they have used inexpensive acid dyes and salt-forming compounds of 2-alkyl-4,5-dihydroimidazole as colorants. By using this method, these problems were solved and the present invention was completed.

That is, the present invention provides an aliphatic hydrocarbon solvent and/or an alicyclic hydrocarbon solvent, and 2 represented by the following general formula.
The gist of the present invention is an oil-based ink composition comprising a salt-forming compound of -alkyl 4,5-dihydroimidazole and an acidic dye, and a film forming agent.

general formula (In the formula, n is an integer from 4 to 20) Next, the present invention will be explained in detail.

The 2-alkyl 4,5-dihydroimidazole that can be used in the present invention is usually made into a salt with an acidic dye as shown in the following formula to solubilize the dye.

(In the formula, n represents an integer of 4 to 20, D represents an acidic dye residue, and XH represents an anionic dissociative group.

) In other words, oil-soluble acid dyes, which are originally water-soluble, are salted with 2-alkyl 4,5-dihydroimidazole that dissolves in aliphatic hydrocarbon solvents and/or alicyclic hydrocarbon solvents. A salt-forming compound is dissolved in the solvent to form an oil-based ink.

Since this oil-soluble salt-forming compound exists in the form of a salt in the solvent, it is stably dissolved.

2-Alkyl 4,5-dihydroimidazole is extremely easy to synthesize and its manufacturing cost is low, as when the alkyl group is long, it is quaternized to produce a cationic activator.

The synthesis method was published by Nikka, 1973.2366, Kiji, Yamada,
As described by Mr. Ito, N-acyl ethylene diamine is prepared from fatty acid methyl ester and ethylene diamine, and this is heated, dehydrated, and cyclized to obtain 2-alkyl 4.5 dihydroimidazole.

As the 2-alkyl 4,5-dihydroimidazole that can be used, 2-butyl 4,5-dihydroimidazole, 2
-Amyl 4,5-dihydroimidazole, 2-hexyl 4,5-dihydroimidazole, 2-hentyl 4,5-
Dihydroimidazole, 2-octyl 4,5-dihydroimidazole, 2-nonyl 4,5-dihydroimidazole, 2-decyl 4,5-dihydroimidazole, 2-dodecyl 4,5-dihydroimidazole, 2-tetradecyl 4,5- Dihydroimidazole, 2-hexadecyl 4
・5-dihydroimidazole, 2-octadecyl 4.5
There is dihydroimidazole.

Examples of acidic dyes that can be used to form salts with this 2-alkyl 4,5-dihydroimidazole include CI Acid Yellow 1 and CI Acid Yellow 3.
, 7, 11, 17, 19, 23, 25, 29, 36, 38, 42, 44, 49, 6
1, 70, 72, 76, 78, 79, 13
1, 135, 141, CI Acid Orange 1,
Same 7, Same 8, Same 10. Same 19, same 20. 24, 28
, 41. Same 43, Same 51, Same 56, Same 63, Same 65,
67, CI Acid Red 1, 6, 8, 9,
13, 14, 18, 26, 27, 32, 35, 37, 42, 51, 80, 82, 8
5, 87, 88, 89, 92, 94, 97
, 106, 111. Same 114, Same 117, Same 118
, 119, 129, 131, 134, 138
, 145, 149, 158, 249, 257
, 265, 266, CI Acid Violet 7
, 11, 15, 34, 41, 43, 48,
49, CI Acid Blue 1, 9, 15, 2
2, 23, 25, 27, 29, 40, 41
, 43, 45, 59, 62, 74, 78,
82, 83, 92, 93, 103, 112
, 113, 117, 120, 126, 127
, 129, 138, 140, CI Acid Green 3, 9, 16, 19, 20, 25, 2
7, 28, 36, 40. 41, 44, CI Acid Brown 2, 4, 13, 14, 20,
Same 27, CI Acid Black 1, Same 2, Same 7, Same 2
4, 26, 29, 31, 48, 50. 94
There is.

Next, examples of aliphatic hydrocarbon solvents and alicyclic hydrocarbon solvents as low odor and low toxicity solvents to replace aromatic hydrocarbon solvents include normal hexane with a boiling point of 40'C or higher;
isohexane, normal heptane, normal octane,
Isooctane, normal decane, and mixtures thereof include petroleum benzine, petrol ligroin, kerosene, petroleum spirit, petroleum naphtha, and cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, and the like.

Here, even if the 2-alkyl-4.5-dihydroimidazole and the acid dye are added to the solvent at the same time, the salt-forming reaction occurs quickly, so that an oil-based ink can be obtained.

This salt-forming reaction does not occur because an aliphatic hydrocarbon solvent and/or an alicyclic hydrocarbon solvent is used as a solvent, but rather because the solvent dissolves 2-alkyl-4,5-dihydroimidazole. If so, it can be used as an ink, but in the present invention, aliphatic hydrocarbon solvents and/or alicyclic hydrocarbon solvents are used because of their low odor and toxicity.

The oil-based ink prepared as described above is the same as the oil-based ink obtained by dissolving in advance a salt-forming compound obtained by reacting 2-alkyl-4,5-dihydroimidazole with an acid dye in a solvent. .

Also, if necessary, an aromatic hydrocarbon solvent such as benzene,
Toluene, xylene, etc. can also be added.

Resins are used as film forming agents, such as alkylphenols, novolac resins, coumaron-indene resins, modified rosin resins, and modified alkyd resins.

As an oil-based ink composition, a salt-forming compound of 2- to 4-alkyl 4.5-dihydroimidazole and an acidic dye is used.
It is desirable to contain 5-30% by weight of resin and 50-80% by weight of solvent.

If necessary, add an oil-soluble activator, rust preventive agent, and antistatic agent.

The present invention will be specifically explained below based on Examples, and in the Examples, "parts" represent "parts by weight".

Example 1 2-dodecyl 4,5 dihydroimida 15 partsol and Eisen Acid Red Phloxine PB (CI Acid Red.

75 parts of normal octane (manufactured by Hodogaya Chemical Co., Ltd.) 10 parts of hytanol 1133 (manufactured by Hitachi Chemical Co., Ltd.) A salt-forming dye obtained by reacting an aqueous solution of Phloxine PB at room temperature in advance and then separating and drying it is dissolved together with normal octane and hytanol 1133, or by adding hytanol 1133.2-dodecyl 4,5 dihydroimidazole to normal octane at room temperature. , Aisen Acid Phloxine PB was added and dissolved by stirring to obtain a good red oil-based ink.

Example 2 2-Octadecyl 4,5-dihydroimidazole Patent Flu VX (CI Acid Blue 1, manufactured by Igawara Chemical Co., Ltd.) 15 parts 15 parts Ligroin 60 parts Coumaron resin (manufactured by Nippon Steel Chemical Co., Ltd.) 10 parts Preparation of ink is as follows A blue oil-based ink was obtained in exactly the same manner as in 1.

Example 3 2-Octyl 4,5-dihydroimidazole Nigrosine NB Conc (CI Acid Black 2, manufactured by Igawara Kagaku Co., Ltd.) Ethylcyclohexane Hallinister L (manufactured by Hatamakasei Co., Ltd., modified rosin resin) 20 parts 10 parts 55 Part 15 parts The above ingredients were stirred at room temperature to obtain a black oil-based ink.

Suminol Milling instead of Nigrosin NB Conch
Black 8BX (manufactured by Igawara Kagaku Co., Ltd.), Kayanol Milling Black VLG (manufactured by Hitachi Chemical Co., Ltd.), Diazid Fast Black BR Conc (manufactured by Mitsubishi Chemical Co., Ltd.) 1
Even if 0 parts were used, a black oil-based ink was obtained.

Example 4 2-butyl 4-yl 5-dihydroimidazo 10 parts Eisen acid floxine PB (CI acid red 92, manufactured by Hodogaya Chemical Co., Ltd.) 5 parts normal octane 75 parts Hytanol 1133 (octylphenol novolac resin, manufactured by Hitachi Chemical Co., Ltd.) ) 10 parts The above ingredients were stirred at room temperature to obtain a red oil-based ink.

As explained above, the oil-based ink of the present invention uses an acid dye and a 2-alkyl-4, which are inexpensive and whose hue can be selected arbitrarily.
・Uses a salt-forming compound with 5-dihydroimidazole as a coloring agent and does not use a solubilizing agent, so the writing marks do not become sticky, and since a salt-forming dye with an activator is not used, the writing marks are immersed in water. The dye has good water resistance when used, and since it is not an acid amide dye derived from an acid dye or an alkyl group-substituted dye, it does not require a complicated process for dye synthesis, and therefore has the advantage of providing an inexpensive dye.

In short, the handwritten marks made using the ink of the present invention dry quickly, and the density did not decrease even after being immersed in running water for one month.

In a comparative example that did not use the ink of the present invention, the ink did not dry quickly and remained sticky for three days, and the density clearly decreased after being immersed in running water for one month.

Claims (1)

[Scope of Claims] 1. An aliphatic hydrocarbon solvent and/or an alicyclic hydrocarbon solvent, and 2-alkyl 4.5 represented by the following general formula.
- a salt-forming compound of dihydroimidazole and an acid dye;
An oil-based ink composition comprising a film-forming agent. General formula (in the formula, n is an integer of 4 to 20).