JPH09165545A - Aqueous metallic color ink composition and writing tool using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous metallic color ink composition and a writing tool using the same, capable of maintaining the re-dispersion property of a pigment for a long period of time without damaging the basic performance such as the adhering property of a printed line so as to use stably and repeatedly. SOLUTION: This ink composition contains at least an aluminum powder pigment, water and a resin, and uses an acrylic emulsion and an alkaline viscosity increasing emulsion simultaneously as the above resin. The total blending amount of the acrylic emulsion and the alkaline viscosity increasing emulsion is preferably >=3wt.% and <5wt.% in terms of the solid components based on the total of the ink composition. Also, the writing tool has an ink tank for holding the above aqueous metallic color ink composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aqueous metallic color ink composition and a writing instrument using the same. More specifically, it relates to a water-based metallic ink composition for exhibiting a color tone having a metallic luster used for a writing instrument such as a paint marker, a felt-tip pen, a writing pen, and a ball-point pen, and a writing instrument characterized by holding the ink composition. is there.

[0002]

2. Description of the Related Art Conventionally, fine metal powder such as aluminum powder has been used as a pigment in order to exhibit a color tone having a metallic luster such as silver or gold, but in the case of water-based ink, the dispersion medium is water. Therefore, the metal powder reacts with water and deteriorates, and it is difficult to maintain stable ink characteristics.When used in a writing instrument, the pressure in the ink tank increases due to the generation of hydrogen gas, which causes ink ejection. there were. Also, as with ordinary water-based inks, when a pigment is dissolved in an alcohol such as isopropyl alcohol together with a resin as a fixing agent and redispersed in water, the metal powder precipitates due to the presence of highly polar alcohol and the surface of the coating film is There was also the inconvenience that it could not occupy and sufficient metal gloss could not be expressed. Therefore, in order to solve these problems and put the aqueous metallic color ink using aluminum powder into practical use, various studies have been made in the past. For example, in JP-A-2-69580, deterioration of the aluminum powder is suppressed by using the aluminum powder in a paste form by adding additives such as a hydrocarbon solvent and an ester wax. Also, JP-A-63
In Japanese Patent Laid-Open No. 95277, addition of an amphoteric compound such as an amino acid is intended to prevent corrosion of an aluminum powder pigment. On the other hand, in Japanese Patent Laid-Open No. 63-72771, an acrylic emulsion is combined with a water-soluble resin such as polyvinyl alcohol and a cellulose resin,
By adjusting the viscosity range suitable for writing instruments, the dispersibility is improved and the aluminum powder is prevented from settling.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention JP-A-63-72
The proposal of Japanese Patent No. 771 solves the problem that when an acrylic resin emulsion is used, the dispersibility of an aluminum powder pigment is improved, but the viscosity of the ink is increased, which makes it unsuitable for use as an ink for writing instruments. . That is, by combining it with a water-soluble resin such as polyvinyl alcohol or a cellulosic resin, it is possible to reduce the ink viscosity to a range suitable for use as a writing instrument and to prevent gelation and to stabilize the ink as an ink. ing. However, when the above proposed ink is stored in a writing instrument and used, if left for a long period of time, the aluminum powder pigment having a large specific gravity will settle and harden. However, there is a problem that it becomes difficult to restore the uniform ink.
Also, if the cap is repeatedly attached and detached, dry and semi-dried films and solidified substances are accumulated on the pen tip part, etc., and the initial outflow state cannot be obtained, and scratches etc. occur and satisfactory drawing lines are obtained. There is also the problem of disappearing. These are serious problems for inks for writing instruments which are supposed to be used for a long period of time, and it is indispensable to solve these problems for practical use as inks for writing instruments. This problem remarkably occurs particularly in a writing instrument having a fine writing nib portion for writing a thin drawing line.

In view of various problems in the above-mentioned conventional aqueous metallic color inks, an object of the present invention is to maintain high dispersibility of aluminum pigments and to prevent strong aggregation even in the case of sedimentation. Another object of the present invention is to provide an ink composition which is difficult to dry by facilitating redispersion of sediment and improving water retention. Further, by utilizing the characteristics of the above-mentioned ink composition, when the ink is used while being held, it is difficult to be clogged, and it is difficult to dry, and it is always stable for a long period of time without causing writing defects such as scraping. It is intended to provide a writing instrument that can supply a writing line.

[0005]

Means for Solving the Problems The inventors of the present invention have made extensive studies as to improvement of the ink composition in order to achieve the above-mentioned object, in particular, a resin component affecting the dispersibility of a pigment, The present invention has been completed by finding that the above drawbacks can be solved while maintaining high dispersibility of an aluminum pigment by using an acrylic emulsion as a resin together with an alkali thickening emulsion.
That is, according to the present invention, a water-based metallic color ink composition for a writing instrument, which contains at least an aluminum powder pigment, water and a resin, wherein an acrylic emulsion and an alkali thickening emulsion are used in combination as the resin. A water-based metallic color ink composition for a writing instrument is provided. In addition, the total blending amount of the acrylic emulsion and the alkali thickening emulsion is
3% by weight or more in terms of solid content based on the total ink composition 5
An aqueous metallic color ink composition for a writing instrument, which is less than wt% is provided. Also provided is a water-based metallic color ink composition for a writing instrument, which contains a polyvinylpyrrolidone resin or polyethylene oxide as a fixing aid.

Further, according to the present invention, there is provided a writing instrument comprising an ink tank for containing ink and an applicator, wherein the ink tank holds the water-based metallic color ink composition of the present invention. . In particular, the writing implement applicator is a holder that holds the ball and the ball in the exposed state.The ball is spring-loaded to open and close the opening composed of the ball and the tip of the holder to prevent ink from leaking out. A writing instrument characterized by being controlled is provided.

In the present invention, the reason why the use of an acrylic thickening emulsion in combination with an acrylic emulsion as a resin as a fixing agent is not clear, but the precipitate of the aluminum pigment becomes bulky and soft at the same time. It is hard and does not aggregate. It is presumed that this makes it easier to re-disperse the sediment and keep the ink in a stable system. In addition, by using these resin emulsions together, a water retention effect that cannot be obtained individually is exhibited, and even when used while held in a writing instrument, it does not dry and solidify at the released pen tip, and it is always stable. As a result, the ink composition can flow out, and a good drawing line can be obtained without causing blurring.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is a water-based metallic color ink composition for a writing instrument, which contains at least an aluminum powder pigment, water and a resin, wherein an acrylic emulsion resin and an alkali thickening emulsion are used in combination as the resin. It is characterized by having done. The aluminum powder pigment used in the present invention may be a conventionally known one, and the average particle diameter thereof is usually 5 to 40 μm, but in consideration of stability of ink for writing instruments, clogging resistance, etc. Those having a particle size in the range of 5 to 20 μm are preferable. Further, it is preferable that the surface of the aluminum powder pigment is subjected to rust-prevention treatment in order to prevent the oxidation of the aluminum powder pigment in the water system. The aluminum powder pigment may be mixed as it is with each of the mixed components, or may be used by being wetted with a hydrocarbon solvent such as mineral terpene in advance in a paste form. When used in a paste form, a commercially available water-dispersible aluminum paste can be used. Examples of commercially available products include products 1500MA and WB1130 manufactured by Toyo Aluminum Co., Ltd., product name F500SIW manufactured by Showa Aluminum Powder Co., Ltd., product name STAPA Hydrolac-W8 manufactured by Ekart Co., Ltd.
n. , STAPA Hydrolac-WH8n. 1.
Etc. can be suitably used. The aluminum powder pigment plays a role of being arranged on the surface of the coating film to give metallic luster of metallic color.

The acrylic emulsion resin used in the present invention contains an acrylic component such as an acrylic ester polymer, a styrene-acrylic acid ester copolymer, an acrylic ester-vinyl acetate copolymer, an acrylic ester-vinylidene chloride copolymer. It is an emulsion resin of various polymers including. The acrylic component also includes acrylic acid, methacrylic acid, and alkyl esters thereof. The acrylic emulsion resin is generally one in which polymer particles containing an acrylic component covered with a hydrophilic protective layer are dispersed in water, and in the present invention, at the same time as dispersing an aluminum pigment, it is applied to a paper surface or the like. It is the main constituent of the film solidification action of the ink described. The acrylic emulsion resin of the present invention has an average particle size of polymer particles of 0.05 to 0.
It is preferable to use an emulsion having a viscosity of 3 μm and a viscosity of 5000 cp or less, and an acid value of the polymer component of 40 to 1
The range of 10 mg / g is preferable. Here, the acid value means the number of mg of potassium hydroxide required to neutralize the acidic substance contained in 1 g of the sample. This is because the use of an emulsion resin having an acid value of the polymer component in the above range facilitates re-dissolution even when a dry film of ink is formed. That is, it is possible to provide an extremely excellent ink in which writing defects are less likely to occur due to drying of the pen tip portion. A commercially available product can be used as the acrylic emulsion resin of the present invention. For example, J-4 manufactured by Johnson Polymer Co., Ltd.
50, the same J-741, the product names Mohvinyl 877 and Howinth 747 manufactured by Hoechst Synthetic Co., Ltd., the product names AE-166 and AE-333 manufactured by Nippon Synthetic Rubber Co., Ltd., Rohm and Haas Co., Ltd. Product names E-1124, E-1552 and the like can be preferably used.

The alkali thickening emulsion used together with the acrylic emulsion resin in the present invention is a resin emulsion such as an acrylic resin. The alkali-thickening type emulsion is generally a polymer particle containing a high concentration of a hydrophilic group because one monomer of the dispersoid copolymer is a highly hydrophilic monomer such as an unsaturated carboxylic acid. It has a core / shell structure composed of a shell and a core having a low concentration, and when added under an alkali or with an alkali agent, it causes dissolution and swelling, thereby increasing the viscosity of the system, and is an O / W type emulsion. . The alkali-thickening emulsion used in the present invention preferably has an average particle diameter of polymer particles of 0.05 to 0.3 μm and an emulsion viscosity of 5000 cp or less. Further, this resin emulsion can be selected and used in a state of being an unneutralized emulsion as it is or in a state of being neutralized and dissolved in advance. A commercially available product can be used as the alkali thickening emulsion of the present invention. For example, product name A manufactured by Rohm and Haas Co., Ltd.
SE-60, TT-615, TT-935, RM
-5, trade name Movinyl LDM manufactured by Hoechst Gosei Co., Ltd.
7010, product name NIKAS manufactured by Nippon Carbide Co., Ltd.
OL-VT-253A, trade name Y1000 manufactured by High Pressure Gas Industry Co., Ltd., trade name B-013 manufactured by Nippon Shokubai Co., Ltd., trade name Polysol AT2040 manufactured by Showa Highpolymer Co., Ltd. and the like are preferably used.

In the present invention, the alkali thickening emulsion and the acrylic emulsion resin are used in combination. By using these resins in combination, it becomes possible to control the sediment of the aluminum pigment having a large specific gravity. That is, in the present invention, by combining the acrylic thickening emulsion with the acrylic emulsion as the resin as the fixing agent,
The aluminum pigment precipitate becomes bulky and at the same time becomes soft and hard and does not aggregate. This facilitates redispersion of the sediment, and the ink can be maintained as a stable system. Further, by using the above two types of resin emulsions in combination, a water retaining effect that cannot be obtained individually is exhibited, and even when used while being held in a writing instrument, the pen tip portion that has been released does not dry and solidify, The ink composition can always flow out stably, and good lines can be obtained without causing blurring.

In the present invention, the total blending amount of the acrylic emulsion and the alkali thickening emulsion is 3% by weight or more and less than 5% by weight in terms of solid content with respect to the entire ink composition. The solid content of 3% by weight or more and less than 5% by weight means that when the solid content is less than 3% by weight, the precipitation of the aluminum pigment having a large specific gravity is controlled, that is, the precipitation is made bulky. This is because the performance of facilitating redispersion due to the softening effect is poor, and the water retaining effect cannot be exerted, and when it is blended in an amount of more than 5% by weight in terms of solid content, the redispersibility of the aluminum powder pigment is of course. This is because there is no problem with the water retention effect and the like, but the resin content is too large, and when it is used for a writing instrument having a thin pen tip portion, the adverse effect due to the formation of a dry film by repeated use becomes large. Further, the compounding ratio of the acrylic emulsion and the alkali thickening emulsion in this case is limited to 50: 1 to 3: 1, and usually 20: 1 to 5: 1.
Range.

As described above, in the water-based ink composition of the present invention, the total amount of the acrylic emulsion resin and the alkali thickening emulsion added is from 3% by weight to 5% by weight.
By setting the range to, for example, a pen core used for markers which is hardened with a fiber bundle resin or the like at the pen tip, and a plastic formed by extrusion molding having continuous pores inside ( Material is polyacetal, etc.)
With a writing instrument having a fine writing nib such as an outer diameter of 2 mm or less, a writing failure due to drying of the nib is less likely to occur. In addition, although it is feared that the adhesiveness will be slightly lowered due to the reduction of the emulsion resin, in the case of using it for a fine writing applicator, the adhesiveness mentioned above can provide a practically sufficient adhesiveness. This is because the area of the drawn line is small, and the phenomenon such as line breakage due to the strain of the coating film during drying does not occur, and especially when writing on the absorption surface typified by the paper surface, the acrylic emulsion resin and alkali Due to the good water retention due to the effect of using the thickening emulsion resin together, it is difficult for the water in the ink to rapidly penetrate into the inside of the paper, so it is possible to obtain a uniform dry coating film with less bleeding, It is presumed that these are the actions that, in spite of the small amount of the resin emulsion and the like, provide practically sufficient adhesion.

Further, in the present invention, if necessary, a polyvinylpyrrolidone resin or polyethylene oxide can be used as a fixing aid. Similar to general water-soluble resins, these auxiliaries adjust the viscosity of the system by a bridge effect between polymer particles and supplement the ink fixing property. In addition, since the addition of these auxiliaries does not cause aggregation of the emulsion resin or the like, the stability of the ink, the aggregation preventing effect of the aluminum pigment which is the characteristic of the ink of the present invention, the redispersibility of sediment, and the water retention property. It is possible to adjust the viscosity and further improve the adherence of the drawn line without impairing the property. In addition to the above components, a color pigment, a pH adjusting agent, a wetting agent, an antiseptic agent, an antifungal agent, and an anticorrosive agent can be appropriately added to the ink shown in the present invention as necessary. .

Next, a writing instrument containing the aqueous metallic color ink of the present invention will be described. As described above, in view of various problems in the conventional water-based metallic color ink, the ink composition of the present invention maintains high dispersibility of the aluminum pigment, and further, strong aggregation even in the case of sedimentation. It is possible to prevent the above-mentioned problems, redisperse the sediment, improve the water retention property, and have the property of being difficult to dry. Therefore, for example, a pen core used for markers that are hardened with a fiber bundle resin or the like at the pen tip part, or a plastic (material such as polyacetal) pen core formed by extrusion molding having continuous pores inside is used. The writing instrument we have, and the outer diameter of the pen core is 2 mm
Regardless of the form of the applicator, such as the following writing instruments for fine writing,
It can be used for all writing instruments consisting of an ink tank that contains ink and an applicator, and when used while being held by the writing instrument, the details of the writing instrument do not easily become clogged, and the pen tip does not dry. It is difficult, and it is possible to supply a stable writing line for a long period of time without causing writing defects such as blurring.

FIG. 1 is a cross-sectional explanatory view of a writing instrument having a ball valve operating mechanism according to an embodiment of the present invention. In FIG. 1, the writing instrument comprises an ink tank 1 for containing ink and an applicator, and the applicator is a ball 2 and a holder 3 for holding the ball in an exposed state. The outflow of ink is controlled by the ball valve action that opens and closes the opening formed by 2 and the tip of the holder 3. That is, when not in use, the ball is pressed by the spring to close the tip of the holder, but during writing, writing pressure is applied to the ball, and a gap is created between the ball and the tip of the holder, so that the required amount of ink flows out. Therefore, an excess ink does not stay in the pen tip portion, and a dry film is unlikely to occur. Due to the structural characteristics of this writing instrument, the excellent water retention of the ink composition of the present invention, and the difficulty of forming a dry film due to repeated use of the ink, writing defects such as blurring may occur for a long time even under severe use conditions. It is possible to always obtain a stable writing line without causing any trouble. On the other hand, when the conventional water-based metallic color ink is used for a writing instrument having a ball valve action mechanism, clogging occurs between the ball and the tip of the holder, which makes it difficult to use stably for a long period of time. The ink composition of the present invention is excellent in redispersibility of an aluminum pigment, and thus is not easily clogged, and not only a marker type writing instrument but also a writing instrument having a ball valve action mechanism as shown in FIG. Can also be used.

The balls constituting the ball valve operating mechanism may have a spherical diameter of 0.7 to 1.5 mm, but 1.0 to 1.2 mm is more preferable. The inner diameter of the tip of the holder and the strength of the spring are adjusted so that a writing pressure is applied to the ball during writing and a gap of about 0.03 to 0.1 mm is generated between the ball and the tip of the holder. The ball 2 of the writing instrument and the holder 3 that holds the ball in the exposed state are made of metal and a rigid body. This is to prevent the pen tip portion from being deformed by repeated use, and to completely control the outflow of ink by opening and closing the opening portion. As a result, fiber bundle resin,
The durability is superior to that of a writing instrument having a pen core made of plastic.

[0018]

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the following examples. (Example 1) 15.0 parts of an aluminum paste, 20.0 parts of an acrylic emulsion, 0.5 part of an alkali thickening emulsion, 0.3 part of a preservative, and 0.1 part of a rust preventive agent were added with purified water. After adjusting the amount to 100 parts, the components were adjusted and then stirred and mixed at room temperature for about 1 hour to obtain a silver metallic color ink composition. Aluminum paste has a pigment content of 68%
Non-leafing type aluminum paste manufactured by Toyo Aluminum Co., Ltd., water-based Alpaste 1500
MA was used. Acrylic emulsion has a solid content of 42
%, And an acid value of 100, John Cryl J-450 manufactured by Johnson Polymer Co., Ltd. was used. The alkali-thickening emulsion is also an acrylic emulsion and has a solid content of 2
8% of Rohm and Haas Co., Ltd. Primal A
SE-60 was used. As a preservative, Proxel XL-2 manufactured by ICI Corporation was used. Benzotriazole was used as the rust preventive agent. The obtained ink composition was filled in the following three types of sample pens and tested for redispersibility, stickiness, and writing stability in repeated writing. The test results are shown in Table 1 together with the results for the ink compositions of Examples 2 to 6 and Comparative Examples 1 to 6 below. The sample pen 1 has a pen tip made of a polyester fiber bundle resin processed body having an outer diameter of 5 mm, and is a valve mechanism that opens and closes by pumping the pen body from an ink storage section in a barrel made of polypropylene. It is a type of marking pen in which ink is sent to a pen body via a pen. The sample pen 2 is a marking pen using the same pen core with the outer diameter of 2 mm as the pen tip in the same container as the pen 1. The sample pen 3 is a marking pen having a ball valve operating mechanism of the present invention, which has an applicator capable of controlling the outflow of ink and an ink tank for storing the ink and has the same shape as that of FIG. It is a marking pen having a shaft of 1 mm and the same shaft as the pen 1. In each of the sample pens, the barrel, which is the ink reservoir, has an inner diameter of 10 mmφ and a length of 10 cm and is made of polypropylene.

The test methods and evaluation criteria for redispersibility, stickiness, and writing stability in repeated writing are as follows. 1. Redispersibility Each pen was filled with one stainless steel stirring ball having a diameter of 5 mmφ and a predetermined amount of ink, and then the cap was capped and left in a constant temperature bath at 50 ° C. for one month upward. After standing, the marking pen was shaken, and the number of times until the stirring ball inside started to move was examined. ◯: Stirrer ball starts to move after shaking 1 to 3 times △: Stirrer ball starts to move after shaking 3 to 5 times ▲: Stirrer ball starts to move after shaking 5 to 10 times ×: Shake up to 10 times Stirrer does not move

2. Adhesiveness Each pen is filled with a predetermined amount of ink, and the pen 1 and pen 2 are impregnated with a sufficient amount of ink by the pumping operation of the pen tip, and then the pen (polyethylene terephthalate) film with a diameter of 3 cm The spiral writing was 30 cm long. After the drawn line was dried, cellophane tape was attached to the coated surface of the line, a 200 g weight was left for 1 hour, and the line was peeled off to examine the degree of peeling of the drawn line. ○: No peeling of drawn line △: Some peeling of drawn line ▲: Marked peeling of drawn line ×: Complete peeling of drawn line

3. Writing stability 1 (repeated writing) Each pen is filled with a predetermined amount of ink, and for pen 1 and pen 2, the pen core is soaked with sufficient ink by the pumping operation of the pen tip, and then the diameter is 5c on the PPC paper.
A spiral writing of m was performed for 1 m, and after writing, it was left facing upward (the coating portion was facing up) for 1 hour without a cap. After standing, the mixture was shaken and stirred well, and the same test as described above was repeated. (For pen 1 and pen 2, pumping is performed twice after 1 m writing). Conditions at the time of the test are temperature 25 ° C and humidity 65%
And "Spiral writing 1m Writing → (Pen tip pumping 2
The number of cycles until writing becomes impossible despite the remaining ink when the number of cycles is “1 hour) → 1 hour after cap off”. ⊚: Writing was possible even after 50 cycles or more, and there was no line blur. ◯: Writing was possible even after 50 cycles or more. (Triangle | delta): It became impossible to write in 30 to 50 cycles. ▲: Writing became impossible after 10 to 30 cycles. X: Writing became impossible after 1 to 10 cycles.

4. Writing stability 2 (repeated writing) Each pen is filled with a specified amount of ink, and pen 1 and pen 2 are soaked into the pen core with a sufficient amount of ink by the pumping operation of the nibs, and then the diameter is 5c on the PPC paper.
A spiral writing of m was performed for 1 m, and after writing, it was left for 1 hour in a thermostatic chamber at 50 ° C. with the cap facing upward (the coating portion was facing upward). After standing, the pen was taken out again, returned to room temperature, shaken and stirred well, and the same test as described above was repeated. (For pen 1 and pen 2, pumping is performed twice after 1 m writing). When 1 cycle of "spiral writing 1 m writing → (pen tip pumping 2 times) → 50 ° C. cap off for 1 hour" was set as one cycle, the number of cycles until writing was impossible despite ink remaining was examined. ⊚: Writing was possible even after 50 cycles or more, and there was no line blur. ◯: Writing was possible even after 50 cycles or more. (Triangle | delta): It became impossible to write in 30 to 50 cycles. ▲: Writing became impossible after 10 to 30 cycles. X: Writing became impossible after 1 to 10 cycles.

Comparative Example 1 A silver metallic color ink composition was obtained in the same manner as in Example 1 except that the alkali thickening emulsion was not added. (Comparative Example 2) The components were adjusted in the same manner as in Example 1 except that the amount of the alkali thickening emulsion was increased to 2.0 parts without adding the acrylic emulsion, and the silver metallic color was changed by the same method. An ink composition was obtained. (Comparative Example 3) Polyethylene oxide which is a water-soluble resin as a fixing aid without adding an acrylic emulsion.
The components were adjusted in the same manner as in Example 1 except that 0 part was added, and a silver metallic color ink composition was obtained by the same method. As polyethylene oxide, PEO-1 manufactured by Sumitomo Seika Chemicals Co., Ltd. was used.

(Example 2) Acrylic emulsion 1
Reduced to 0.0 parts and alkali thickened emulsion 1.0
The ingredients were adjusted in the same manner as in Example 1 except that the amount was increased.
A silver metallic color ink composition was obtained by the same method. (Comparative Example 4) A silver metallic color ink composition was obtained in the same manner as in Example 2, except that the alkali thickening emulsion was not added. (Comparative Example 5) The components were adjusted in the same manner as in Example 2 except that 1.5 parts of water-soluble resin polyethylene oxide was added as a fixing aid without adding the alkali thickening emulsion, A silver metallic color ink composition was obtained by the method.

Example 3 The components were adjusted in the same manner as in Example 2 except that 1.5 parts of the water-soluble resin polyvinylpyrrolidone was added as a fixing aid, and a silver metallic color was prepared by the same method. An ink composition was obtained. As polyvinylpyrrolidone, PVP K-90 manufactured by Gaf Co. was used. (Comparative Example 6) The ingredients were adjusted in the same manner as in Example 3 except that the amount of polyvinylpyrrolidone, which was a fixing aid, was increased to 3.0 parts without adding an acrylic emulsion, and a silver-colored product was prepared by the same method. A metallic color ink composition was obtained.

(Example 4) Aluminum paste 12.
0 part, acrylic emulsion 10.0 parts, alkali thickening type emulsion 1.0 part, polyethylene oxide 1.5 parts which is a water-soluble resin as a fixing aid, preservative 0.3
Parts, rust preventive agent 0.1 parts, yellow pigment toner 20.0 parts, and red pigment toner 2.0 parts to make 100 parts, and after adjusting the components, by stirring and mixing at room temperature for about 1 hour. A golden metallic color ink composition was obtained. The yellow pigment toner uses a 15% acrylic pigment-dispersed acrylic resin-based aqueous toner, and the red pigment toner uses a 15% CI pigment red 17-based acrylic resin-dispersed aqueous toner. The toner has a predetermined amount of compound and an average particle diameter of about 100 to 300 nm (nanometer).
Dispersed by a bead mill for about 30 minutes, and then added.

(Example 5) Aluminum paste 12.
0 part, acrylic emulsion 10.0 parts, alkali thickening emulsion 1.0 part, preservative 0.3 part, rust preventive agent 0.1 part, yellow pigment toner 10.0 parts, blue pigment toner 10.0 Purified water was added to 100 parts to make 100 parts, and after adjusting the components, a green metallic color ink composition was obtained by the same method as in Example 4. Blue pigment toner is pigment (CI P
igment Blue 15) Aqueous toner containing 15% acrylic resin dispersion was used.

(Example 6) An acrylic emulsion having a solid content of 47% and an acid value of 30 is Johnson Polymer Co., Ltd.
Jonkrill J-90 manufactured by K.K.
Components were adjusted in the same manner as in Example 3 except that parts were made, and a silver metallic color ink composition was obtained by the same method.

[0029]

[Table 1]

From the results of Example 1 and Comparative Example 1 and Comparative Example 2 and Example 2 and Comparative Example 2 and Comparative Example 4, the redispersibility and the writing can be improved by using the emulsion resin and the alkali thickening emulsion in combination. It can be seen that the performance for stability is produced. From a comparison between Example 1 and Example 2, it can be seen that when the compounding amount of the resin is reduced, the compounding amount is suitable for fine writing pens such as pen 2 and pen 3.
From Example 3 and Example 6, it can be seen that the ink composition of Example 3 using an emulsion resin having a higher acid value has better writing stability. Further, when the water-soluble resin which is the above-mentioned fixing aid is added for the purpose of supplementing the fixing property as in Examples 3 and 6, excellent writing stability may be exhibited as in the case of no addition. I understand. On the other hand, from the results of Example 1 and Example 2, Comparative Example 3 and Comparative Example 6, from the viewpoint of adhesion and writing stability, it is possible to use a water-soluble resin instead of the emulsion resin, It can be seen that the redispersibility is poor. Also, naturally, it becomes impossible to give water resistance to the drawn line. Further, it can be seen from Examples 4 and 5 that the composition of the present invention can be applied to a system of metallic color ink to which a coloring pigment is added. On the other hand, for pen 1, pen 2 and pen 3,
Comparing the test results, the pen 3 has a valve mechanism in the applicator portion, that is, a ball valve mechanism by spring repulsion. Therefore, even under severe conditions such as the test 4, the pen 1 and the pen 2 It can be seen that even better writing stability over time is exhibited.

[0031]

The aqueous metallic color ink composition for a writing instrument of the present invention maintains the redispersibility of the pigment for a long period of time without impairing the basic performance such as the adherence of the drawn line with the ink, and particularly repeats Exhibits excellent writing stability during use. Further, by using it together with the writing instrument of the present invention, better writing stability over time can be realized.

[Brief description of the drawings]

FIG. 1 is a cross-sectional explanatory view of a writing instrument having a ball valve operating mechanism according to an embodiment of the present invention.

[Explanation of symbols]

 1. Ink tank 2. Ball 3. Holder 4. Spring 5. Dedication

Claims (5)

[Claims] 1. An aqueous metallic color ink composition containing at least an aluminum powder pigment, water and a resin, wherein an acrylic emulsion and an alkali thickening emulsion are used in combination as the resin. Metallic color ink composition. 2. The aqueous metallic color according to claim 1, wherein the total amount of the acrylic emulsion and the alkali thickening emulsion is 3% by weight or more and less than 5% by weight in terms of solid content based on the total ink composition. Ink composition. 3. The aqueous metallic color ink composition according to claim 1, further comprising a polyvinylpyrrolidone resin or polyethylene oxide as a fixing aid. 4. An ink tank for containing ink and an applicator, wherein the ink tank is provided in the ink tank.
A writing instrument, which holds the water-based metallic color ink composition as described above. 5. The ink applicator of the writing instrument is a holder for holding the ball and the ball in a state of being exposed, and the ball is repelled by a spring to open and close an opening formed by the ball and the tip of the holder. A writing instrument, which controls the outflow of water, and holds the aqueous metallic color ink composition according to claim 1, 2 or 3 in the ink tank.