JPH07119383B2 - Aqueous erasable marking pen ink composition - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to an aqueous erasable marking pen ink composition, and more particularly to a water-based non-absorbent or non-permeable writing surface, typically a so-called white plate. And a marking pen ink composition having excellent erasability of handwriting written on a writing surface.

Conventional technology Conventionally, the handwriting written on a non-absorbent or non-penetrative writing surface is wiped off from the writing surface by lightly rubbing it with a dry cloth or soft paper. Various marking pen ink compositions are known. Such a conventional erasable marking pen ink composition, in general,
Along with organic solvents, pigments and resins, it contains an additive called a release agent, for example, in Japanese Examined Patent Publication No. 62-9149.
There is described an erasable marking pen ink composition obtained by dissolving a substance selected from a surfactant and a saturated aliphatic carboxylic acid triglyceride in an organic solvent together with an aliphatic dibasic acid ester and an aliphatic monobasic acid ester.

However, such a conventional erasable marking pen ink composition uses ketones or alcohols as a solvent as described above. Especially, among these solvents, ketones are highly toxic. Among alcohols, methanol is highly toxic and has a bad odor. On the other hand, ethanol, although relatively less toxic, adds to the cost of raw materials.

On the other hand, conventionally, for example, JP-A-60-179478 and JP-A-60-179478.
As described in JP-A-60-219273, an aqueous ink composition obtained by containing a resin emulsion such as a polyvinyl acetate resin as a release agent in water together with a dye or pigment as a colorant and a predetermined surfactant. Things are known. However, since such an ink composition uses a resin emulsion as a release agent, in the handwriting on the non-absorbing surface, after the drying, a continuous film of the resin emulsion is formed on the writing surface as in the case of so-called strippable paint. Therefore, the handwriting is peeled off in the form of a continuous film, and if the handwriting is lightly abraded, the handwriting is not easily peeled off from the writing surface, and it is said that it has excellent erasability. hard.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present inventor has conducted diligent research to solve the above-mentioned problems in conventional oil-based and water-based erasable marking pen ink compositions, and as a so-called handwriting release agent,
Aqueous emulsion of aliphatic carboxylic acid ester that is liquid at room temperature, higher hydrocarbon that is liquid at room temperature, for example, aqueous emulsion of liquid paraffin, or emulsion of higher alcohol that is liquid at room temperature is used together with a water-soluble resin. Therefore, it was found that it is possible to obtain an aqueous erasable marking pen ink composition in which only the handwriting portion rubbed with a dry cloth or the like can be easily peeled off from the writing surface.
The present invention has been achieved.

Means for Solving the Problems The erasable marking pen ink composition according to the present invention comprises (a) water as a solvent, (b) a colorant dissolved or dispersed in water, (c) (1) at room temperature A liquid aliphatic carboxylic acid ester emulsion, (2) a higher hydrocarbon emulsion that is liquid at room temperature, or (3) a higher alcohol emulsion that is liquid at room temperature, and (d) a water-soluble resin. To do.

In the marking pen ink composition according to the present invention,
Water is used as the solvent. The amount of water in the ink composition is usually 50 to 90% by weight, preferably 60 to 80% by weight.
Is the range.

In the marking pen ink composition according to the present invention, a pigment is preferably used as the colorant. Examples of pigments include carbon black, phthalocyanines such as copper phthalocyanine blue, azo, quinacridone, anthraquinone, dioxane, indigo, thioindigo, perinone, perylene, indolenone, azo-
Any one such as azomethine type can be used. Already, a dispersion prepared by dispersing various pigments in water is commercially available,
Also in the present invention, such commercially available products can be preferably used. The pigment dispersion, as a pigment dispersant,
Since various resin dispersants, surfactants, etc. may be blended, the ink composition according to the present invention may also contain such resins, surfactants, etc. The pigment dispersant is known per se and is usually used in the range of 1 to 300 parts by weight, preferably 5 to 100 parts by weight, relative to 1 part by weight of the pigment.

In the present invention, a dye can also be used as the colorant. In this case, a water-soluble dye is preferably used as the dye.

The colorant is usually 1 to 30% by weight in the ink composition.
The content is preferably in the range of 5 to 20% by weight. When the colorant is contained in an excessive amount, the viscosity of the ink composition is too high, resulting in inferior writability,
The erasability is also reduced. On the other hand, when the content of the coloring agent is too small, the handwriting density is low, which is not practical.

Next, in the ink composition according to the present invention, as a release agent for handwriting, an aliphatic carboxylic acid ester which is liquid at room temperature,
A higher hydrocarbon that is liquid at room temperature or a higher alcohol that is liquid at room temperature is contained in an aqueous emulsion state.

As the aliphatic carboxylic acid ester, the ester is preferably a monobasic acid ester, dibasic acid diester, monohydric or diester of dihydric alcohol, or monohydric, di or triester of trihydric alcohol.
Particularly preferred specific examples include monobasic acid esters, particularly propyl myristate, which is a higher fatty acid ester,
Butyl palmitate, butyl stearate, etc. Dialkyl esters of dibasic acid dialkyl didecyl dodecane, dipropyl adipate, dioctyl sebacate, dioctyl azelate, etc., dihydric alcohol esters propylene glycol monostearate, propylene glycol Decanoic acid diester, natural or synthetic fatty acid triglyceride which is a trihydric alcohol triester, and trimethylolpropane triisostearate. These are used alone or as a mixture of two or more kinds.

As the higher hydrocarbon as a stripping agent, what is usually called fluid paraffin, squalane, or the like is preferably used, but it may be partially oxidized, for example, polyethylene oxide wax. The higher alcohol that is liquid at room temperature is not particularly limited, but for example, hexyl alcohol, octyl alcohol, lauryl alcohol, etc. are preferably used.

The aqueous emulsion of such aliphatic carboxylic acid ester, higher hydrocarbon or higher alcohol can be prepared by a usual emulsification method. Moreover, a commercial item can also be used. Further, if necessary, two or more aqueous emulsions of an aliphatic carboxylic acid ester, a higher hydrocarbon or a higher alcohol may be added to the ink composition.

In the ink composition according to the present invention, the aliphatic carboxylic acid ester, higher hydrocarbon or higher alcohol as a release agent is contained in the ink composition in an amount of 1 to 20% by weight, preferably 5 to 15% by weight. It In the ink composition, when the compounding amount of the aliphatic carboxylic acid ester, the higher hydrocarbon or the higher alcohol is less than 1% by weight, sufficient handwriting erasability cannot be obtained, while
Even if the content is too much over 20% by weight, the handwriting will be extended and the writing surface will be stained, and the erasability of the handwriting will be deteriorated.

Furthermore, the ink composition according to the present invention improves the film-forming property and leveling property of the handwriting on the writing surface, and is excellent in the erasability of the handwriting, and at the same time, the ink composition has an appropriate viscosity to improve the writing property. A water-soluble resin is contained in order to increase
As the water-soluble resin, for example, an originally water-soluble synthetic resin such as polyvinylpyrrolidone, polyvinyl alcohol having a polymerization degree of 100 to 3000 and a saponification degree of 50 mol% or more is preferably used.

However, in addition to this, originally water-insoluble acrylic resin, styrene-maleic anhydride resin, maleated oil,
Maleated polybutadiene, maleated alkyd resin,
A water-soluble resin that is water-solubilized by salt formation such as sodium salt of maleated petroleum resin, sodium salt of maleated rosin ester resin, alkali metal salt of potassium salt, ammonium salt, amine salt and the like is also preferably used. Furthermore, natural water-soluble resins such as gum arabic and serratic can also be used. Among the above, a resin that is inherently water-soluble and a synthetic resin that is salt-solubilized and solubilized are particularly preferably used.

These water-soluble resins are usually used in ink compositions.
It is contained in the range of 0.1 to 15% by weight, preferably 0.3 to 10% by weight.

In the ink composition according to the present invention, preferably, a water-soluble polyhydric alcohol is blended as a release aid in order to enhance the effect of the release agent. Examples of such polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol having a molecular weight of about 200 to 600,
Examples thereof include polypropylene glycol having a molecular weight of 1000 to 3000, glycerin, and trimethylolpropane. Such a polyhydric alcohol is incorporated in the ink composition in an amount of 20% by weight or less, preferably 10% by weight or less. Too much blending in the ink composition in excess of 20% by weight is not preferable because the viscosity of the ink composition becomes excessively high and the writability is lowered.

Further, as another peeling aid, various surfactants may be contained. As such a surfactant, any of anion, nonion, cation, and amphoteric can be used. However, in particular, nonionic surfactants such as carboxylic acid having a polyoxyethylene chain, sulfonic acid type, sulfuric acid ester type, phosphoric acid ester type and the like, anionic surfactants, amphoteric surfactants of alkyl betaine type, fluorine type Surfactants and the like are preferably used. The surfactant is usually contained in an amount of 10% by weight or less, preferably 0.2 to 5% by weight. When blended excessively, the erasability of handwriting is reduced.

The handwriting with the ink composition according to the present invention on the non-absorbent or non-permeable writing surface is formed into a film while the resin contains a colorant when water is evaporated, that is, when the handwriting is dried. On the other hand, the aliphatic carboxylic acid ester as the release agent, the higher hydrocarbon or higher alcohol emulsion is destroyed, and a continuous oily layer is formed between the non-absorptive writing surface and the resin film. Therefore, the handwriting has erasability.

The surfactant as a peeling aid has an effect of assisting the separation of the oily layer and the pigment-containing resin aqueous layer in the handwriting during writing. However, the surfactant also enhances the leveling property at the time of writing, eliminates uneven distribution of the release agent emulsion in the handwriting before drying on the writing surface, and imparts uniform erasability after the handwriting is dried. Have. In particular, these effects are remarkable when a fluorine-based surfactant is used.

Further, the ink composition according to the present invention, as a drying accelerator for improving the dryness of handwriting, is usually 15% by weight or less based on the ink composition, preferably to the extent that the emulsion contained in the ink composition is not destroyed. 1-10% by weight
The lower aliphatic alcohol may be contained within the range.
In particular, ethanol, propanol or butanol is preferably used.

In addition to the above, the ink composition may optionally contain any pH adjuster, preservative, preservative, etc., which are usually blended with the aqueous ink composition.

EFFECTS OF THE INVENTION The erasable marking pen ink composition according to the present invention uses water as a solvent, in which an aliphatic carboxylic acid ester, a higher hydrocarbon or a higher alcohol which is liquid at room temperature is dispersed in an aqueous emulsion state as a release agent. In addition, since it is a water-based ink composition containing a water-soluble resin, there is almost no problem of toxicity, odor and irritating odor in conventional oil-based ink compositions, and the above-mentioned release agent has a handwriting After drying, a continuous oily layer is formed on the writing surface, the resin film containing the colorant is separated from the writing surface, and the water-soluble resin improves the film-forming property and leveling property of the handwriting on the writing surface. Therefore, like the conventional oil-based erasable marking pen, by lightly rubbing the handwriting with a dry cloth, paper, or the like, only the rubbed portion can be easily peeled and erased.

Furthermore, according to the ink composition of the present invention, since the release agent is a hardly volatile liquid substance, even after a long time has passed after writing,
Since it still exists between the writing surface and the resin film containing the colorant, the erasability of the handwriting is effectively retained.

EXAMPLES The present invention will be described below with reference to examples and reference examples, but the present invention is not limited to these examples. In the Reference Examples and Examples, parts and% indicate parts by weight and% by weight, respectively.

First, as a reference example, a preparation example of an aqueous emulsion of an aliphatic carboxylic acid ester will be shown.

Reference Example 1 67 parts of water, 30 parts of butyl stearate and nonionic surfactant Neugen EA-120 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., HLB12)
3 parts were stirred and emulsified with a homogenizer to obtain an aqueous emulsion of butyl stearate.

Reference Example 2 71 parts of water, 25 parts of dioctyl dodecanedioate, 0.8 part of nonionic surfactant Surfactant 80 (manufactured by Kao Corporation) and 3.2 parts of nonionic surfactant Tween 80 (manufactured by Kao Corporation) (interface) Stirring agent HLB12.8) was stirred and emulsified with a colloid mill to obtain an aqueous emulsion of dioctyl dodecanedioate.

Example An aqueous marking pen ink composition having the components shown below was prepared. In the following, a dispersion means a pigment dispersion, a resin means a water-soluble resin, an activator means a surfactant, and a desiccant means a drying accelerator. The number of parts in the pigment dispersion indicates the number of parts by weight used in the preparation of 100 parts by weight of the ink composition, and the% number in the other components is the effective substantial amount compounded amount by the weight% in the ink composition (total amount 100% by weight). Means the rest is water.

Ink composition 1 Colorant (50 parts of carbon black dispersion ¹⁾ Carbon black 7.5% Resin Water-soluble acrylic resin 1.0% Release agent Butyl stearate 7.0% Isopropyl myristate 3.0% Activator Hytenol 18E ²⁾ 0.5% Florard FC -430 ³⁾ 0.3% desiccant Isopropanol 8.0% Ink composition 2 (Comparative example) Colorant (Carbon black dispersion ⁴⁾ 55 parts) Carbon black 5.5% Resin-free release agent Butyl palmitate 5.0% Dioctyl dodecanedioate 5.0% Liquid Paraffin 3.0% Activator Hitenol NE-05 ²⁾ 0.5% Trax K-40 ⁵⁾ 0.2% Unidyne DS-20 ⁶⁾ 0.2% Desiccant Ethanol 5.0% Ink Composition 3 Colorant (Special Black TU Paste ⁷⁾ 20 Part) Carbon black 5.0% Resin polyvinyl alcohol 2.5% Release agent Butyl isostearate 8.0% Triglyceride 3.0% activator Unidyne DS-401 ⁶⁾ 0.3% desiccant without ink composition 4 colorant (copper phthalocyanine blue dispersion ⁸⁾ 40 parts) of 0.5% copper phthalocyanine blue 6.0% resin acacia stripper butyl stearate 5.0% palmitic Butyl acid 3.0% Dioctyl sebacate 3.0% Activator Persoft SK ⁹⁾ 0.5% Amhthol 24B ¹⁰⁾ 0.5% Unidyne DS-402 ⁶⁾ 0.3% Drying agent Isopropanol 5.0% Ink composition 5 Colorant (Flexonyl blue AN ¹¹⁾ 20 parts) Pigment 5.0% Resin Polyvinyl alcohol 2.0% Release agent Isopropyl myristate 8.0% Polypropylene glycol (average molecular weight 300) 2.0% Activator Florard FC-430 ³⁾ 0.4% Drying agent Ethanol 5.0% Ink composition 6 Colorant (flexo) Niruretsudo FGR-LA ¹²⁾ 15 parts) pigment 5.0% resin water-soluble acrylic resin 3.0% release agent azelaic Dioctyl 5.0% diisopropyl adipate 5.0% activator HITENOL N-08 ²⁾ 0.4% Polystar AAM-550 ¹³⁾ 0.2% desiccant isopropanol 6.0% Ink composition 7 colorant Blue No. 1 5.0% resin polyvinyl alcohol 3.5% release agent Butyl stearate 10% Activator Unidyne DS-401 ⁶⁾ 0.4% Desiccant Isopropanol 6.0% Ink composition 8 Colorant (25 parts of carbon black dispersion) Carbo black 5.0% Resin polyvinyl alcohol 10% Release agent Butyl stearate 10% Activator Nitsukor ECT-7 ¹⁵⁾ 2.0% No desiccant Ink composition 9 (Comparative example) Colorant (25 parts of carbon black dispersion) Carbon black 5.0% No resin Release agent Butyl stearate 10% Activator Nitzkor ECT-7 ¹⁵⁾ 2.0% desiccant without ink composition 10 colorant (carbon black dispersion 25 parts Carbon black 5.0% resin without stripper butyl stearate 10% active agent Nitsukoru ECT-7 ¹⁵⁾ None 2.0% desiccant Note 1) carbon black 15%, 65% water, styrene - butyl acrylate - methacrylic acid copolymerization Combined amine salt 20
% Dispersion.

2) Polyoxyethylene alkyl ether sulfate ester salt (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).

3) Fluorine-based surfactant (Sumitomo 3M Limited).

4) A dispersion consisting of 10% carbon black, 67% water, 20% water-soluble acrylic resin, 2% ammonia water and 1% surfactant.

5) Polyoxyethylene alkyl ether sulfate ester salt (manufactured by NOF CORPORATION).

6) Fluorine-based surfactant (manufactured by Daikin Industries, Ltd.).

7) Pigment dispersion (manufactured by Hoechst).

8) A dispersion comprising 15% of copper phthalocyanine, 75% of water, and 10% of styrene-methyl methacrylate-hydroxymethyl methacrylate-acrylic acid copolymer ammonium salt.

9) Alkyl sulphate sodium salt (manufactured by NOF CORPORATION).

10) Alkyl betaine type amphoteric surfactant (Kao Corporation)
Made).

11) Pigment dispersion (made by Hoechst).

12) Pigment dispersion (made by Hoechst).

13) Polycarboxylic acid type polymeric anionic surfactant (manufactured by NOF CORPORATION).

14) Polyoxyethylene alkyl ether carboxylic acid (manufactured by Nippon Surfactant Industry Co., Ltd.).

Each of these ink compositions was used to write on a non-absorbent writing surface made of enamel, and after 5 minutes, the dry handwriting was lightly rubbed with a dry cloth to eliminate the handwriting erasability (initial erasability). The same erasability (erasability over time) after standing for 15 days at a temperature of 25 ° C. and a relative humidity of 60% was examined. The results are shown in Table 1. In addition, the evaluation was made by visually observing four grades, that is, ⊚ is extremely good, ◯ is good, Δ is slightly bad, and x is bad.

Even when the writing surface was made of a melamine resin or a fluorine-based resin, almost the same results as shown in Table 1 were obtained.

For comparison, an oil-based erasable marking pen ink composition using a conventional commercially available ketone solvent or alcohol solvent was similarly tested, and the results are shown in Table 1.

The ink composition containing the water-soluble resin has improved initial erasability and erasability over time as compared with the same ink composition except that the water-soluble resin is not contained.

Claims (5)

[Claims] 1. (a) Water as a solvent, (b) a colorant dissolved or dispersed in water, (c) (1) emulsion of an aliphatic carboxylic acid ester which is liquid at room temperature, (2) at room temperature A water-based erasable marking pen ink composition comprising a liquid higher hydrocarbon emulsion or (3) a higher alcohol emulsion liquid at room temperature, and (d) a water-soluble resin. 2. The aliphatic carboxylic acid ester is a monobasic acid ester, a dibasic acid diester, a dihydric alcohol mono- or diester, or a trihydric alcohol mono-, di- or triester. A water-based erasable marking pen ink composition. 3. The water-based erasable marking pen ink composition according to claim 1, which contains a polyhydric alcohol as a release aid. 4. The aqueous erasable marking pen ink composition according to claim 1, which contains an aliphatic alcohol as a drying aid. 5. The water-based erasable marking pen ink composition according to claim 1, which contains a surfactant.