JP3158309B2 - Aqueous marking ink composition for writing board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous marking ink for a writing board, and more particularly to a non-absorbable polypropylene plastic board, a melamine baked board, an enameled board,
A water-based marking ink for writing boards that can be written on a writing board such as a fluororesin film and that can be easily erased by lightly rubbing the handwriting with a dry cloth or flexible paper. is there.

[0002]

2. Description of the Related Art There have been known various marking ink compositions for writing boards which can be easily erased by gently rubbing handwriting on a non-absorbing writing board with a dry cloth or soft paper. ing. Such a conventional marking ink composition for a writing board generally contains an additive called a release agent together with an organic solvent, a pigment and a resin. For example, Japanese Patent Publication No. 62-9149 discloses that a fatty acid ester and / or a higher hydrocarbon and a surfactant are used as a release agent, and an organic solvent is used as a solvent.

However, organic solvents used in conventional marking ink compositions for writing boards include methyl isobutyl ketone, butyl acetate, ethanol, and isopropanol.
In recent years, thinner solvents have been replaced by alcohol solvents due to toxicity problems, but have the drawback of strong odor and irritation.

In order to avoid these drawbacks, it has been practiced to use water as a solvent and to use it in the form of an emulsion as a release agent. For example, see, for example,
No. 7 discloses water as a solvent, a colorant, resins such as polyvinyl acetate, vinyl acetate-acrylic copolymer, alkyd resin or urethane having film forming properties at room temperature, and aliphatic as a handwriting release agent. An aqueous erasable marking pen ink composition containing an emulsion of a hardly volatile liquid compound selected from a carboxylic acid ester, a higher hydrocarbon and a higher alcohol is disclosed, and JP-A-1-252681. In the gazette, water as a solvent, a colorant dissolved or dispersed in water, an emulsion of an aliphatic carboxylic acid ester liquid at room temperature as a release agent, an emulsion of a higher hydrocarbon liquid at room temperature, and a liquid at room temperature In addition to using a higher alcohol emulsion, a water-soluble resin, a polyhydric alcohol or a surfactant as a release aid, and a lower aliphatic alcohol as a drying aid. - Aqueous erasability Ma was added Le - King ink composition is described.

However, when these aqueous erasable marking ink compositions are written on a writing board with the same composition, and immediately after the handwriting has dried, the writing board tends to be stained when rubbed with a dry cloth or the like. Was. This is because the film is not sufficiently formed immediately after the emulsion resin itself dries, and when rubbed with a dry cloth or the like, the pigment and the release agent component remain on the writing board and stain the writing board. .

[0006]

The present inventors have conducted intensive studies to solve the above-mentioned problems in the conventional oil-based and water-based marking ink compositions for writing boards, and as a result, have found that water-soluble resins are used as resins. Used, hexadecyl 2-ethylhexanoate emulsion having good compatibility with the water-soluble resin,
By using a water-soluble resin in combination with an incompatible monobasic aliphatic carboxylic acid ester emulsion and / or a phthalic acid ester emulsion, only a handwriting portion lightly rubbed with a dry cloth or the like is used as a writing plate. The present invention has been made to obtain a marking ink composition for a writing board which can be easily peeled off from an ink, and an object of the present invention is to provide an aqueous marking ink for a writing board having excellent properties. Providing a composition.

[0007]

The gist of the present invention is to provide a writing board containing water as a solvent, containing a water-soluble resin, an aqueous dispersion of a pigment colorant, and an aliphatic carboxylic acid ester emulsion which is liquid at ordinary temperature. In the aqueous marking ink composition, a hexadecyl 2-ethylhexanoate emulsion is used as the aliphatic carboxylic acid ester-based emulsion and is selected from the group consisting of a monobasic aliphatic carboxylic acid ester emulsion and a phthalic acid ester emulsion. A water-based marking ink composition for a writing board, wherein at least one kind or two or more kinds are used.

In the present invention, a polyalkylene oxide compound and a polyvalent carboxylic acid are used as the water-soluble resin.
It is preferable to use a water-soluble resin which is a hydrophilic high molecular weight compound having a weight average molecular weight of 10,000 or more obtained by reacting the anhydride or its lower alkyl ester or diisocyanate, and a fluorine-based surfactant Is preferably contained.

Usually, as a release agent for erasing handwriting written with a marking ink, a resin for softening the resin in the ink composition and a resin for drying the ink composition as a handwriting on a writing board are used. It is necessary to add oily substances that are incompatible with the resin that migrate between the membrane and the writing board. According to the above-mentioned publication, various surfactants and polyhydric alcohols are used as components for softening the water-soluble resin, and various aliphatic oils incompatible with the resin include various aliphatic substances. Emulsions of carboxylic esters, higher hydrocarbons, or higher alcohols have been used.

According to the present invention, an aliphatic carboxylate hexadecyl 2-ethylhexanoate emulsion is used as a component compatible with the resin as a release agent, and an aliphatic carboxylate ester emulsion and / or is used as an incompatible component with the resin. And a phthalic acid ester emulsion.

[0011] When the dry handwriting written on the writing board with the aqueous marking ink composition for a writing board of the present invention is rubbed with a dry cloth or flexible paper, the reason why the writing can be erased is as follows. When the handwriting is dried, the water-soluble resin contains a pigment as a colorant and forms a film in a state softened by compatible hexadecyl 2-ethylhexanoate. On the other hand, a fatty acid ester incompatible with the water-soluble resin is formed. The emulsion or phthalate emulsion can be easily erased because the emulsion is destroyed with the evaporation of water and a continuous oil layer is formed between the writing board and the water-soluble resin film. it is conceivable that.

Further, the present invention will be described in detail. In the aqueous marking ink composition for a writing board according to the present invention, water is used as a solvent. The amount of water in the ink composition is usually 60 to 90%, preferably 70 to 85%.
Range.

In the aqueous marking ink composition for a writing board according to the present invention, the film forming property and leveling property of the writing surface are improved, and when the handwriting is lightly rubbed with a dry cloth or soft paper, Use a water-soluble resin at room temperature so that it can be easily erased. As a water-soluble resin, a polyalkylene oxide compound having a weight average molecular weight of 100 or more obtained by addition-polymerizing an alkylene oxide containing ethylene oxide to an organic compound having two active hydrogen groups and a polycarboxylic acid, an anhydride thereof or a lower alkyl thereof. A hydrophilic high molecular weight compound having a weight average molecular weight of 10,000 or more obtained by reacting with an ester or diisocyanate is preferred.

In the polyalkylene compound, the organic compound having two active hydrogens as a starting material includes:
For example, ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, 1,
6-hexanediol, aniline and the like. Examples of the alkylene oxide added to the organic compound include, for example, ethylene oxide alone or a mixture of ethylene oxide and propylene oxide, butylene oxide, styrene oxide, α-olefin epoxide, glycidyl ether, and the like.

The addition polymerization of the alkylene oxide is carried out by a known method. The addition method of the ethylene oxide and the other alkylene oxide can be appropriately selected, for example, by mixing or by polymerization in a block. Examples of the polycarboxylic acid, anhydride or lower alkyl ester thereof to be reacted with the polyalkylene oxide compound include phthalic acid, isophthalic acid, adipic acid, fumaric acid, malonic acid, maleic acid and terephthalic acid. And carboxylic acids such as sebacic acid, dimer acid and pyromellitic acid. Examples of the lower alkyl ester include a methyl ester, a dimethyl ester, and a diethyl ester. The most preferred specific examples are dimethyl terephthalate, dimethyl phthalate, dimethyl isophthalate, dimethyl adipate, dimethyl sebacate, and pyromellitic anhydride. This polymerization reaction is carried out at 120 to 250 ° C. and 10 to ^{4 to} 76.
It is preferable to carry out under the condition of 0 Torr. Examples of diisocyanates include tolylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and 4,4'-methylene- Bis (cyclohexyl isocyanate) and the like. This urethanization reaction can be obtained, for example, by mixing at an NCO / OH equivalent ratio of 1.5 to 0.5 and performing the reaction at 80 to 150 ° C. for 1 to 5 hours. The high molecular weight compound has a weight average molecular weight of 1
It is preferably at least 000. The water-soluble resin is contained in the ink composition in an amount of 0.1 to 15%, preferably 0.3 to 10%.

In the marking ink composition according to the present invention, a pigment is used as a colorant. Examples of pigments include carbon black, azo-based, phthalocyanine-based, and indanthrene-based pigments such as slenble. These pigments are used as a pigment colorant liquid, that is, as a pigment dispersion. Various resin-based dispersants are preferably used as the pigment dispersant. When a surfactant type dispersant such as polyoxyethylene nonylphenyl ether is used, the resin film is softened more than necessary, the drying property deteriorates, and when the white plate is wiped off after writing on the white plate, it is not preferable. . The amount of the pigment in the pigment colorant liquid is 20 to 35%,
The amount of the dispersant is 6 to 12 based on 30 parts of the pigment in a solid content ratio.
Used in the range of parts. The colorant liquid is usually contained in the ink composition in an amount of 1 to 30%, preferably 5 to 2%.
It is contained in the range of 0%. When the colorant liquid is contained in an excessive amount, the viscosity of the ink composition is too high, so that the writability is poor and the erasability is low. On the other hand, when the content of the colorant liquid is too small, the density of the handwriting is too low to be practical.

In the ink composition according to the present invention, hexadecyl 2-ethylhexanoate, which is compatible with the above water-soluble resin, is selected from aliphatic carboxylic acid esters which are liquid at normal temperature as a release agent for handwriting. Compatible aliphatic carboxylic esters and / or phthalic esters are used in the form of an aqueous emulsion. The concentration of hexadecyl 2-ethylhexanoate in the aqueous emulsion is 25 to
55%. As the aliphatic carboxylic acid ester incompatible with the water-soluble resin, a monobasic acid ester is preferably used. Specific examples include methyl oleate, butyl oleate, 2-ethylhexyl palmitate, isopropyl isostearate, isocetyl stearate, isocetyl isostearate, and isostearyl palmitate. These are used alone or as a mixture of two or more. Lid as release agent
Dibutyl phthalate, dioctyl phthalate, and the like are used as the luate. The concentration of these carboxylic acids in the emulsion is between 25 and 55%.

In the emulsion of such an aliphatic carboxylic acid ester or phthalic acid ester, storage stability over time is important, and there should be no separation such as creaming during storage. Glycerin is usually used as a stabilizer. As the emulsifier, fatty acid soap, alkyl soda sulfate or sorbitan surfactant is used. The emulsification method can be prepared by a method using an ordinary emulsifier.

In the ink composition according to the present invention, a hexadecyl 2-ethylhexanoate emulsion which is compatible with the water-soluble resin as a release agent is contained in the ink composition in an amount of 1 to 3%.
It is contained in an amount of 10%, preferably 2 to 8%. or,
The aliphatic carboxylic acid ester emulsion or phthalic acid ester emulsion incompatible with the water-soluble resin is preferably 1 to 10%, more preferably 2 to 10% in the ink composition.
It is contained in the range of 8%. In the ink composition, when the total content of the aliphatic carboxylic acid ester emulsion or the phthalic acid ester emulsion is less than 1%, sufficient handwriting erasability cannot be obtained.
Excessive addition of more than 0% results in extended handwriting and stains the writing surface, and on the contrary, lowers the erasability of the handwriting.

In the ink composition according to the present invention, a fluorine-based surfactant is used as a film forming aid. When a fluorine-based surfactant is not added, writing on a writing board such as a polypropylene board or a melamine baked board with a writing board results in poor ink transfer and poor writability. The amount of the fluorine-based surfactant is usually 5% or less, preferably 0.1% or less.
It is contained in the range of 2-3%. In the ink composition according to the present invention, a lower aliphatic alcohol may be added to accelerate the drying of the handwriting. Ethanol or isopropanol is preferably used for the lower alcohol, but it is usually 1 to the extent that the emulsion in the ink composition is not destroyed.
The content is 0% or less, preferably 5% or less.

[0021]

The present invention will be described below with reference to examples. The percentages or parts in the examples are% by weight or parts by weight. First, reference examples 1 and 2 show adjustment examples of the water-soluble resin as reference examples. Reference Example 1 So-called polyethylene glycol obtained by adding ethylene oxide to ethylene glycol (weight average molecular weight 1
(0000) 100 parts of dimethyl terephthalate 2.2
Parts by weight and a polyesterification reaction to obtain a weight average molecular weight of 1
30,000 compounds were obtained. Reference Example 2 A polyalkylene oxide compound (weight average molecular weight of 20,000) obtained by subjecting bisphenol A to block addition polymerization of 85% of ethylene oxide and 15% of propylene oxide.
0) in 100 parts of hexamethylene diisocyanate.
84 parts and a small amount of dibutyltin dilaurate
Urethane at 00 ° C. to give a weight average molecular weight of 250,
000 hydrophilic polymer compounds were obtained. Next, reference examples 3 and 4 show preparation examples of an emulsion of an aliphatic carboxylic acid ester as reference examples.

REFERENCE EXAMPLE 3 35 parts of water, 50 parts of hexadecyl ethylhexanoate, 3 parts of sodium oleate, 2 parts of sodium lauryl sulfate, and 10 parts of glycerin were stirred and emulsified with a homogenizer to obtain 2ethylhexanoic acid. A hexadecyl emulsion was obtained. Reference Example 4 56 parts of water, 30 parts of butyl oleate, sorbitan nonionic surfactant Nonion OP80R (manufactured by NOF Corporation) 3.18
0.82 parts of nonionic OT221 (manufactured by NOF Corporation) was stirred and emulsified with 10 parts of glycerin using a homogenizer to obtain a butyl oleate emulsion.

Next, as reference examples, preparation examples of pigment colorant liquids are shown in Reference Examples 5 to 8. Reference Example 5 26 parts of carbon black, John Krill 62 [acrylic styrene resin-based dispersant, Johnson Polymer Co., Ltd.] 1
7.0 parts, Azitol XW393 [Defoaming agent, Hoechst Co., Ltd.] 0.02 parts, Bioside 880 [Mold inhibitor, Daisho Co., Ltd.] 0.10%, Water 56.88 parts in a pot mill And crushed overnight to obtain a black colorant solution. Reference Example 6 30 parts of Slenble-B [Dainichi Seika Co., Ltd.], 27.3 parts of Joncryl 61-J [acrylic styrene resin-based dispersant, Johnson Co., Ltd.], Azitol XW3930.02
, 0.10 part of Bioside 880 and 42.58 parts of water were ground overnight in a pot mill to obtain a blue colorant liquid.

Reference Example 7 Poppy Red GG (Dainichi Seika Co., Ltd.) 30 parts, Joncryl 61-J 27.3 parts, Azitol XW393 3.0 parts.
02 parts, Bioside 880 0.10 parts, water 42.58
The part was crushed overnight with a pot mill to obtain a red colorant liquid. Reference Example 8 Wet cake of Shanning Line 2GN [moisture 60.
9%, Dainichi Seika Co., Ltd.] 76.73 parts, John Krill 6
1-J 21.9 parts, Azitol XW393 0.02
, 0.10 part of Bioside 880 and 0.69 part of water were ground in a pot mill overnight to obtain a green colorant liquid.

[0025]

EXAMPLES The composition ratio of the marking ink composition for a writing board according to the present invention is shown below as examples. Example 1 Black pigment colorant liquid (Reference Example 5) 10.0% The above water-soluble resin (Reference Example 1) 20.0% 2-ethylhexanoic acid hexadecyl emulsion 6.7% Butyl phthalate emulsion 6.7 % Florad FC128 ¹ ) 0.3%
Water 51.3% Ethanol 5.0%

Example 2 Blue pigment colorant liquid (Reference example 6) 10.0% Water-soluble resin (Reference example 1) 20.0% 2-ethylhexanoic acid hexadecyl emulsion 6.7% Dibutyl phthalate emulsion 6.7% Florad FC128 0.3%
Water 51.3% Ethanol 5.0%

Example 3 Red pigment colorant liquid (Reference Example 7) 10.0% The above water-soluble resin (Reference Example 1) 20.0% 2-ethylhexanoic acid hexadecyl emulsion 6.7% 2-ethylhexyl valmitate emulsion 6 0.7% Florad FC-128
0.3% Water 51.3% Ethanol 5.0%

Example 4 Green pigment colorant liquid (Reference Example 8) 10.0% The above water-soluble resin (Reference Example 1) 20.0% 2-hexadecyl 2-ethylhexanoate emulsion 6.7% Isopropyl isostearate 6.7 % Florad FC-128 0.3%
Water 51.3% Ethanol 5.0% (Note) 1) Fluorinated surfactant, manufactured by Sumitomo 3M Co., Ltd. The ink compositions of Examples 1 to 4 were put in a marker shaft and melamine was added. The handwriting was written on a baked white plate, and after 5 minutes, the handwriting was rubbed with a dry cloth, and the erasing property (initial erasing property) of the handwriting and the erasing property after standing for 15 days (daily erasing property) were examined. Table 1 shows the results.

[0029] (Note) ○: good 1) Solvent is butyl acetate type 2) Solvent is alcohol type As a comparative sample, the erasability was compared with a commercially available organic solvent type marking ink for writing board. The aqueous marking ink for a writing board had good initial erasability and erasability over time.

[0030]

The aqueous marking ink for a writing board according to the present invention uses water as a solvent, the above water-soluble resin, a pigment dispersed in water, a fatty acid ester and / or phthalic acid as a release agent. Since it uses an aqueous emulsion such as an ester, it has no toxicity, odor, or pungent odor as compared with a conventional organic solvent-type marking ink composition for a writing board, and a specific release agent is selected. Therefore, as in the case of a conventional marking ink for a writing board made of an organic solvent, after writing, the handwriting can be erased by lightly rubbing with a dry cloth or paper.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-133477 (JP, A) JP-A-56-41277 (JP, A) JP-A-2-38472 (JP, A) JP-A 55-41 90569 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C09D 11/16

Claims (2)

(57) [Claims] 1. An aqueous marker for a writing board containing water as a solvent, containing a water-soluble resin, an aqueous dispersion of a pigment colorant, and an aliphatic carboxylic acid ester emulsion which is liquid at ordinary temperature.
In the king ink composition, as the water-soluble resin,
Ethylene oxide to an organic compound having two neutral hydrogen groups
Containing addition polymerized alkylene oxide
Luylene oxide compounds and polycarboxylic acids and their anhydrides
Or its lower alkyl ester or diisocyanate
With a weight average molecular weight of 10,000 or more obtained by reacting
Using an aqueous polymer compound, using a hexadecyl 2-ethylhexanoate emulsion as the aliphatic carboxylic acid ester-based emulsion and at least one selected from the group consisting of monobasic aliphatic carboxylic acid ester emulsions and phthalic acid ester emulsions An aqueous marking ink composition for a writing board, wherein one or more kinds are used. 2. The aqueous marking ink composition for a writing board according to claim 1, further comprising a fluorine-based surfactant.