JPS6377982A - Ink composition for marking pen - Google Patents

Abstract

PURPOSE:To obtain the title composition which is nontoxic and has excellent non-drying properties and fluidity, by incorporating a specified organic compound into ethyl alcohol. CONSTITUTION:A solvent comprising ethyl alcohol is mixed with a surface active agent comprising an organic compound (a) of formula I (wherein R is a 16-22C hydrocarbon chain; n is 0-5) in an amount of 0.2-4.0wt%, an organic compound (b) of formula II (wherein R is a 16-18C hydrocarbon chain) in an amount of 0.2-2.0wt%, or an organic compound (c) of formula III (wherein R is a 16-22C hydrocarbon chain) in an amount of 0.2-2.0wt%, and if necessary, a dye and other resin.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an ink composition for marking pens with improved non-drying properties.

(Prior Art) Conventionally, xylene, cellosolve, etc. have been used as solvents for ink compositions for marking pens, but they have had problems with toxicity. Therefore, it is desirable to use ethyl alcohol, which has low toxicity, as a solvent, but ethyl alcohol has the disadvantage that it is highly volatile and requires a short dry-up time, so that it becomes impossible to write on it immediately in the cap-off state. Generally, to improve non-drying properties, medium-to-high temperature solvents and slow-drying solvents are added, but adding these solvents has the disadvantage of halving the low toxicity advantage of ethyl alcohol. Since these solvents have high viscosity, there is a problem that the fluidity of the ink is impaired when the amount added is large.

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide an ink composition for a marking pen that has no toxicity problems, does not have a viscosity so high as to impair fluidity, and has improved non-drying properties. It is something.

(Means for Solving the Problems) The ink composition for marking pens of the present application devised to achieve the above object uses ethyl alcohol as a solvent and has the following molecular formula (% formula %) (R is Hydrocarbon chain having 16 to 22 carbon atoms, n is an integer of 0 to 5) (2) R-100H (R is a hydrocarbon chain having 16 to 18 carbon atoms) (3) R-
In the case of (1), 0.2 to 4.0i of any organic compound represented by OH (R is a hydrocarbon chain having 16 to 22 carbon atoms)
In case of (2), it is added in an amount of 0.2 to 2.0% by weight, and in case of (3), it is added in an amount of 0.2 to 2.0% by weight. In addition, among the above organic compounds, the number of carbon atoms in the hydrocarbon chain of (3) is preferably in the range of 16 to 18. Also, the amount of these organic compounds added is 0.8 to 3.0% by weight in the case of (1), and 0.6 to 3.0% in the case of (2).
1.5% by weight, and in the case of (3), the range of 0.6 to 1.5% by weight is more preferable. If the amount added is too small, the effect will not appear, and conversely, if it is too large, it will not dissolve and will not dissolve. This is because there is a risk of re-precipitation. The ink composition naturally contains the required amount of dye and other necessary resins.

(Function) According to the present invention, when the organic compound of any one of the above (1), (2), and (3) is added as a surfactant, gas and liquid are formed to improve the solvent 6-fund drying properties. Such an organic compound consists of a hydrocarbon chain (R) which is a hydrophobic group, and -(C!HaO)nH1-(X)OH-OH, which is a hydrophilic group. Whether or not these organic compounds form a monomolecular film at the gas-liquid interface is determined by the balance between the degree of affinity for water of the hydrophilic groups and the magnitude of the cohesive force acting between the hydrophobic groups. That is, if the hydrophilicity of the hydrophilic group is weak, it is impossible to form a monomolecular film, whereas if it is too strong, it dissolves in water and a monomolecular film cannot be obtained. Furthermore, the cohesive force of a hydrophobic group increases as the length of the hydrophobic group increases; if the length of the hydrophobic group is too short, the effect of the hydrophilic group tends to overcome this, and the molecules dissolve in water, making it impossible to obtain a monomolecular film. The types and amounts of organic compounds to be added as surfactants presented herein in this application were obtained as a result of intensive research and experiments by the inventors, and are This makes it possible to improve the

(Example) Below, the compositions of the first to fourth examples of the present invention and comparative examples, as well as the experimental results of measuring the time until dry-up, are shown in a table. In addition, appropriate dyes and other additive resins were used in the table, and industrial modified ethyl alpour was used as a solvent.

Composition of First Example Composition of Second Example Composition of Third Example Composition of Fourth Example Comparative Example Experimental Results (Effects of the Invention) As described above, the ink composition for marking pens of the present invention is free from toxicity. There is no need to worry, and the viscosity does not become so high that it impedes fluidity, and it has the effect of extremely improving non-dry properties.

Claims (1)

[Claims] Ethyl alcohol is used as a solvent, and the following molecular formula (1) R-O-(C_2H_4O)_nH (R is a hydrocarbon chain having 16 to 22 carbon atoms and n is an integer of 0 to 5) ) (2) R-COOH (R is a hydrocarbon chain having 16 to 18 carbon atoms) (3) R-OH (R is a hydrocarbon chain having 16 to 22 carbon atoms) In case of (1), 0.
It is characterized in that it is added in a range of 2 to 4.0% by weight, 0.2 to 2.0% by weight in case of (2), and 0.2 to 2.0% by weight in case of (3). Ink composition for marking pens.