JPH0621262B2 - Marking ink composition - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention is directed to a plastic plate with excellent drying resistance against pen tip.
A marking ink composition that can be written on a non-absorbent surface such as a metal plate, enamel plate, or glass plate, and that can be easily erased by gently rubbing the handwriting with a dry cloth or soft paper. It is about things.

(Prior Art) Conventionally, a marking ink composition is known which can be written on a non-absorbing surface and whose handwriting can be easily erased by rubbing. The marking ink composition usually contains a relatively low boiling point organic solvent, a coloring agent, and a coloring agent, so that when it is written on a non-absorbing surface, it rapidly dries to give clear and sharp handwriting.
It is composed of a resin and a release agent. Therefore, when the marking ink composition is used for a writing instrument, if the marking ink composition is left with the cap removed, the organic solvent evaporates from the ink composition at the pen tip portion to deposit a coloring material or resin, and It has the disadvantages of clogging inside and obstructing ink ejection from the pen tip, making the handwriting faint and incapable of writing. Therefore, in order to suppress the evaporation of the solvent from the nib and improve the nib dry resistance, JP-A-58-79067 discloses alkyd amide alcohol and sorbitan fatty acid ester as nib dry resistance improvers. , JP-A-60
No. 84369 discloses saccharose ester.

(Problems to be Solved by the Invention) However, the pen tip drying resistance improver disclosed in the above publication requires a large amount for obtaining practical pen tip drying resistance, and in this case, resin film formation There is a problem that the sharpness of the handwriting is deteriorated, such as the ability being impaired and the handwriting being whitened.

Therefore, it is an object of the present invention to provide a marking ink composition using a pen tip desiccant having a large effect that a practical pen tip desiccation resistance can be obtained by adding a small amount.

(Means for Solving Problems) The present invention includes a coloring material, an organic solvent, a resin soluble in the organic solvent, dioctyl azelate, and the following general formula (1).
A marking ink composition comprising at least a decaglycerin stearate partial ester represented by:

<General formula> (In the formula, R represents a stearyl group or hydrogen.) Hereinafter, the present invention will be described in detail.

In the present invention, the coloring material refers to a pigment, a resin-processed pigment, and a dye that is insoluble in the following organic solvents. As the pigment, conventionally known organic pigments / inorganic pigments and metal powder pigments can be appropriately used, but pigments that can be stably dispersed as fine particles in the ink composition are preferable. In this sense, a resin-processed pigment in which a pigment is kneaded into a resin is preferably used, and in this case, it is preferable to use no resin in the ink composition. As the dye, a dye insoluble in an organic solvent such as a disperse dye or an architectural dye can be used. The amount of the colorant used varies depending on the type of the colorant and other ink components, but is 1 to 20% by weight, preferably 2 to 17% by weight based on the total amount of the ink.

Organic solvents include lower alcohols such as ethanol, propanol, isopropanol and butanol, lower aliphatic ketones such as methyl ethyl ketone and methyl isobutyl ketone, lower alcohol esters of lower fatty acids such as ethyl acetate and butyl acetate, and aromatics such as benzene, toluene and xylene. Examples thereof include group hydrocarbons, alicyclic alcohols, alkyl ethers of glycols, and the like, and these can be used alone or as a mixture of two or more. The amount of these used is 55 to 93% by weight, preferably 70 to 90% by weight
Is.

The resin is used for imparting film-forming ability, adhering to the surface to be coated, and adjusting the viscosity of the ink. Conventionally used natural resins and synthetic resins can be used. Specifically, rosin, rosin Ester, rosin-modified glycerin ester, rosin-modified maleic acid resin, rosin-modified phenolic resin, rosin-modified phenol-glycerin ester and other rosin-based resins, ethyl cellulose, acetyl cellulose and other cellulose resins, petroleum-based resins, ketone resins, polyvinyl butyral, vinyl chloride -Vinyl acetate copolymers, vinylidene chloride-vinyl chloride copolymers and the like can be mentioned, and the use amount thereof is 0.5 to 15% by weight, preferably 2 to 10% by weight based on the total amount of the ink. Dioctyl azelate is used as a release agent that gives a handwriting a property that can be easily erased by rubbing, and the amount used is
1 to 15% by weight, more preferably 3 based on the total amount of ink
~ 8 wt% can be used.

The decaglyceryl stearate partial ester represented by the general formula (1), which is a skeleton of the present invention, is used for improving the nib desiccation resistance, and specific examples include decaglyceryl pentastearate and deca. Glyceryl heptastearate may be used, and its amount used is 0.05 to 5% by weight, more preferably 0.15 to 3% by weight based on the total amount of the ink.
% By weight.

In addition to the above components, if necessary, antiseptics, fungicides,
Various additives such as a wetting agent, a viscosity modifier, an antifreezing agent, an antifoaming agent, and a surfactant can be appropriately used.

Further, the marking ink composition of the present invention can be easily obtained by mixing and dispersing the above-mentioned components with a dispersing machine such as a homomixer, a ball mill and a lab mixer.

(Function) The decaglycerin stearate partial ester represented by the general formula (1) used in the present invention is colloidally and uniformly dispersed in the ink, and the organic solvent in the ink composition evaporates at the pen tip. Then, it deposits at the same time as the resin and forms a very brittle film on the surface of the pen tip. It is considered that this coating suppresses evaporation of the organic solvent, and since this coating is easily destroyed by normal writing pressure, the nib dry resistance is improved. Moreover, this decaglyceryl stearate partial ester has a larger volume when it is dispersed in a solvent in a colloidal form than the above-mentioned other nib drying resistance improvers, so even a small addition amount is sufficient. It has the property of forming a very brittle film on the surface of the pen tip, and this property seems to be useful for producing the effect.

(Examples) Hereinafter, the present invention will be described in more detail with reference to Examples.
In the examples, "parts" means "parts by weight".

The components of Examples 1 and 2 and Comparative Examples 1 to 3 shown in Table 1 below were mixed and dispersed by a homomixer to obtain a marking ink composition.

<Supplementary explanation of Table-1> (1) Fuji AS Black: Fuji Dye Co., Ltd., processed pigment <Pigment: carbon black (45 wt%), resin: polyvinyl butyral (55 wt%)> (2) Fuji AS Red: Fuji Dye Co., Ltd., Processed pigment <Pigment: Insoluble azo pigment (50 wt%), Resin: Polyvinyl butyral (50 wt%)> (3) Fuji IK Blue: Fuji Dye Co., Ltd., Processed pigment <Pigment: Phtharosyanin blue (50 wt%), resin; vinyl chloride / vinyl acetate copolymer (50 wt%)> (4) Decaglin 5-S: Nikko Chemicals Co., Ltd., decaglyceryl pentastearate (5) Softer 1000: Nippon Oil Co., Ltd. ), Alkylamido alcohol (6) Nonion PP-40R: NOF Corporation, sorbitan palmitate (effect of the invention) The marking inks obtained in Examples 1 and 2 and Comparative Examples 1 to 3 above. Using the Narubutsu shown in Table 2. The result of performing nib drying resistance test.

(Note) Test method: Using a fiber core as a pen tip, fill each writing ink composition in a writing instrument using batting, remove the cap and leave it in the room (temperature 20 ° C, humidity 50%), and after leaving it One hour was written every 30 minutes, and after one hour was written every hour, and the time until the handwriting faded was measured.

As described above, the marking ink composition of the present invention has excellent resistance to drying at the nib when used in a writing instrument.

Claims (1)

[Claims] 1. A marking ink composition comprising at least a coloring material, an organic solvent, a resin soluble in the organic solvent, dioctyl azelate and a decaglyceryl stearate partial ester represented by the following general formula (1). object. <General formula> (In the formula, R represents a stearyl group or hydrogen.)