JPH10140071A - Marking ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition that is resistant to drying at the pen point even when a pen is left to stand, as the pen point cap is put off, with high resistance to drying-up, by using a colorant, an organic solvent, an organic solvent-soluble resin and pentaerythritol fatty acid ester. SOLUTION: This marking ink composition comprises (A) a colorant, for example, an oil-soluble dye or pigment in an amount of 1-20wt.%, preferably 2-15wt.%, (B) an organic solvent, for example, a lower alcohol, an aromatic hydrocarbon or a lower aliphatic ketone, in an amount of 50-90wt.%, preferably 70-85wt.%, (C) a resin soluble in said organic solvent which is used as a coating film-forming agent, an adhesive to the face to be coated, or a dispersant for the colorant, for example, rosin or the like, in an amount of 0.1-30wt.%, preferably 1-20wt.% and (D) at least one selected from pentaerytheritol (un)saturated fatty acid esters in an amount of 0.1-10wt.%, preferably 0.1-5wt.%. The objective composition exhibits long-term ink stability and has the effect of pen dry-up prevention.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to a quick-drying marking ink composition, in which the pen tip is difficult to dry for a long time even if the cap is left unattached, and the pen tip has excellent drying resistance. The present invention relates to a marking ink composition that is difficult to improve.

[0002]

2. Description of the Related Art Conventionally, a quick-drying marking ink composition, that is, an oil-based ink, is applied to both an absorbing surface of paper, cloth, etc. and a smooth non-absorbing plate surface of plastic, glass, metal, enamel plate, etc. It is widely used because it is writable and quick-drying. These inks include white marking inks, which are general marking inks that have strong fixation of handwriting and inks that can be erased by lightly rubbing with a dry cloth or the like by adding a release agent. There is.

[0003]

However, the above-mentioned marking ink composition of any type can be used for a writing instrument, and if left without a cap, it will take several tens of minutes and the ink from the pen tip will be insufficient. As the organic solvent of the composition evaporates, the coloring agent, resin, and the like are clogged in the network of the tip of the pen made of felt or the like, and the smooth outflow of the ink is hindered.
This phenomenon is usually called dry-up. As described above, the conventional quick-drying marking ink composition has a dry-up problem when the cap is forgotten. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a marking ink composition which is difficult to dry up and has an effect of preventing dry up.

[0004]

Means for Solving the Problems The inventors of the present invention have made intensive studies and studies to solve the above problems, and as a result, have completed the present invention. The present invention also provides a marking ink composition comprising: an organic solvent; an organic solvent; a resin soluble in the organic solvent; and at least one selected from pentaerythritol fatty acid esters. Hereinafter, each component of the present invention will be described.

The organic solvents used in the present invention include lower alcohols such as ethanol, propanol and isopropanol, aromatic hydrocarbons such as toluene and xylene, lower aliphatic ketones such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate, and the like. Lower alcohol esters of lower fatty acids such as butyl acetate; aliphatic hydrocarbons such as hexane and heptane; alicyclic hydrocarbons such as cyclohexane and ethylcyclohexane; alkyl alcohols of glycol; and the like. These inks are used in an amount of 50 to 90% by weight, preferably 70 to 85% by weight, based on the total amount of the ink.
It is.

The coloring agent used in the present invention includes oil-soluble dyes and pigments. As the oil-soluble dye, almost any general oil-soluble dye that is soluble in an organic solvent can be used. For example, as a dye, Orazole Yellow 2GL
N, Orazole Red 3GL, Orazole Blue 2GL
N, neon zapon blue FLE, spirit black S
P, Balifast Red 1308, Oil Blue BA,
Oil Yellow 185, Oil Red TR71, Oil Black S, etc. The pigment is not particularly limited, and examples thereof include azo pigments, condensed polyazo pigments, phthalocyanine pigments, metal complex salt pigments, thioindigo pigments, and dye lake pigments. , Organic pigments such as fluorescent pigments, and inorganic pigments such as carbon black and titanium oxide. Further, processed pigments having a resin-coated surface, such as various types of Microlith A, AS black, AS blue, and IK red are also used. can do. These dyes and / or
Alternatively, pigments can be used alone or as a mixture. The amount used varies depending on the type of colorant and other ink components, but is 1 to 20% by weight, preferably 2 to 15% by weight based on the total amount of the ink. Is desirable.

[0007] The resin used in the present invention is used as a film-forming agent, an adhesive to the surface to be coated, a viscosity modifier for ink, and also as a dispersant for a colorant, and has been used in the past. Various natural resins and synthetic resins can be used.For example, rosin resins such as rosin, ester gum, maleic acid-modified rosin and phenol-modified rosin, cellulose resins such as ethyl cellulose and nitrocellulose, polyvinyl butyral, vinyl chloride-vinyl acetate Examples thereof include vinyl resins such as copolymer resins, petroleum resins, ketone resins, and acrylic resins. These resins are used in an amount of 0.1 to 30% by weight, preferably 1 to 20% by weight based on the total amount of the ink. It is.

The above-mentioned pentaerythritol fatty acid esters are additives used for preventing the dry-up of the drying resistance of the pen tip. The saturated or unsaturated fatty acids condensed with the pentaerythritol are hydrogen or carbon atoms. It is an alkyl group having 3 to 22 or an alkenyl group having 16 to 22 carbon atoms. However, this excludes the case where all are hydrogen. As the saturated fatty acids, saturated higher fatty acids such as caprylic acid, lauric acid, myristic acid, and stearic acid, and as the unsaturated fatty acids, linoleic acid, linolenic acid,
Pentaerythritol fatty acid esters containing at least one of mono-, di-, tri- and tetraesters such as oleic acid are used. Specific examples include pentaerythritol monooleate, pentaerythritol monostearate, pentaerythritol distearate, and pentaerythritol tetraoleate. These additives are used in an amount of 0.1 to the total amount of the ink.
It is used in the range of 1 to 10% by weight, preferably 0.1 to 5% by weight. Further, if necessary, known fatty acid glycerin esters and sorbitan fatty acid esters can be used in combination.

Further, in order to obtain a white board ink, a type of hand-written ink which can be erased by lightly rubbing with a dry cloth or the like the handwriting written on a smooth non-absorbing plate such as plastic, glass, metal or enamel as described above. In addition to
It is sufficient to add a dispersing agent which is dispersed and has a low vapor pressure than the organic solvent and is hardly volatile or nonvolatile. Examples of the releasing agent include known polyhydric alcohols, paraffins, mineral oils and higher fatty acids. And their esters, polyoxyethylene alkyl ether type and / or polyoxyethylene alkyl phenol ether type or sorbitan ester type nonionic surfactants, various soaps and the like, and these may be used alone or in combination. This can provide handwriting with erasability. In addition to the above components, if necessary, auxiliary agents such as an antifoaming agent, a dispersing agent, a preservative, a wetting agent, a clay modifier, and an antifreezing agent can be appropriately used.

[0010]

[Work] The pentaerythritol fatty acid ester used in the ink of the present invention is characterized in that when the cap is removed from the pen and left for a long time, the organic solvent in the ink composition evaporates and the coloring agent or resin It is believed that the precipitates form simultaneously with the formation of a very weak film, which effectively prevents the organic solvent from further evaporating. However, when writing again, it is thought that this very weak film can be easily written because it is easily broken by normal writing pressure, and the outflow of ink is not hindered.

[0011]

EXAMPLE A colorant and a resin are added to an organic solvent, and about 50 to 8
While heating to 0 ° C, the mixture is stirred or dissolved for about 1 hour to dissolve or disperse. Then, an additive of a dry-up inhibitor and other auxiliaries are added, and the mixture is further stirred for about 1 hour and cooled to room temperature. Various marking ink compositions having the compositions shown in Table 1 were prepared. In addition, the numerical value shown in Table 1 shows weight%.

[0012]

[Table-1]

"Supplementary Explanation of Table 1" (1) Spirit Black SP: Orient Chemical Co., Ltd.
(2) Bali Fast Red 1308: manufactured by Orient Chemical Co., Ltd. (3) Microlith Blue 4G-A: resin processed pigment manufactured by CIBA (4) Denka butyral 3002: butyral resin manufactured by Denki Kagaku (5) Neopolymer 160: Petroleum resin manufactured by Nippon Petrochemical Co., Ltd. (6) PEDS: Pentaerythritol distearate manufactured by Tetsuno Yuka Co., Ltd. (7) PETTO: Pentaerythritol trioleate manufactured by Tetsuno Yuka Co., Ltd.

Using the marking ink compositions obtained in Examples 1 to 3 and Comparative Examples 1 to 3, a dry-up test of a pen tip was performed. Table 2 shows the results.

[0015]

[Table-2]

Test method: As an example, the marking ink composition of each embodiment is filled in a writing implement assembled with a pen tip made of a material obtained by processing a fiber bundle into a resin, and an ink absorber, and the cap is removed to remove the room (temperature). (25 ° C, humidity 60%)
And the handwriting was written every hour after the standing, and the time until the handwriting was blurred was measured.

[0017]

As described above, the ink of the present invention contains pentaerythritol fatty acid esters as additives as described above, and thus has the following effects.

With the ink of the present invention, even when the ink is left with the cap removed, the handwriting does not easily fade and writing is not impossible, and the extremely weak ink formed on the surface of the pen tip is used. The coating film is broken by normal writing pressure, and a handwriting as if immediately after manufacturing is obtained.

Since the ink of the present invention uses pentaerythritol fatty acid esters even after a long time,
The ink shows stability forever and has a stable dry-up prevention effect.

[Table-1]

[Table-2]

Claims (1)

[Claims] 1. A marking ink composition comprising a colorant, an organic solvent, a resin soluble in the organic solvent, and at least one selected from pentaerythritol fatty acid esters.