JP2007031558A - High gloss double coloring ink composition and writing tool using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high gloss double coloring ink composition wherein gloss is excellent, and color development of a pearl pigment is not influenced by a color of an outline, more particularly, influence by a color of an outline in double coloring ink is removed, whereby contrast between a color of a pearl pigment itself and a color of an outline is clearly distinguished to attain a remarkable high gloss double coloring effect. <P>SOLUTION: The high gloss double coloring ink composition comprises (1) a pearl pigment and a powdery metal pigment, (2) water, (3) a water soluble organic solvent comprising at least one of an alcohol, a glycol and a glycol ether, which contains a branched hydrophobic group, and (4) a water soluble dye. A writing tool is manufactured by using the composition as an ink. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a high gloss dual color ink composition and a writing instrument using the same. The present invention also relates to a coloring method using the above composition.

  Double-coloring ink, when written with this, produces a contour line around the handwriting to obtain double-colored handwriting. Used as ink for marking pens, sign pens, water-based ballpoint pens, etc. It is done.

  Conventionally, as a double color ink, for example, a metal powder pigment, a water-soluble dye, water and a penetrating organic solvent, used for writing on a solvent penetrable surface such as paper, cloth, etc., a handwriting formed with a metal powder pigment A double color ink composition is disclosed in which a water-soluble dye permeates and diffuses around the surface to produce a contour effect. (Patent Document 1, Patent Document 2)

  In addition, since the metal powder pigment may be ionized and the water-soluble dye may be reduced during the ionization process, this problem is solved and a double color ink that provides a stable double color effect over a long period of time. A composition is disclosed. (Patent Document 3)

Further, an aqueous high-gloss ink composition is disclosed in which a high-gloss handwriting can be obtained by using a mixture of both pearl pigments and metal powder pigments when used alone. (Patent Document 4)
JP 60-231777 A JP 61-123684 A JP 2000-129188 A Japanese Patent Laid-Open No. 10-245517

  Since these ink compositions use metal powder pigments with excellent concealment properties, the central part of the handwriting shows the original color of the metal powder pigments regardless of the color of the contour line, but the "glossiness" I can't say there is. However, if a pearl pigment is used instead of a metal powder pigment in order to produce a “gloss”, the gloss is obtained, but the pearl pigment itself is poorly concealed, so it is easily affected by the color of the contour line. Even if a pearl pigment is used, there is a problem that it looks completely different depending on the color of the contour line.

  An object of the present invention is to provide a double color ink composition which is excellent in gloss and does not affect the color development of the pearl pigment due to the color of the contour line. That is, while JP-A-10-245517 is intended to improve the design of a single handwriting such as improving the glossiness of a normal handwriting that is not simply a double-coloring ink, the present invention is a double-coloring ink with a double-coloring ink. The two inventions are different from each other in that a remarkable double color effect is obtained by eliminating the influence of the color of the color outline and clearly distinguishing the contrast between the color of the pearl pigment itself and the color of the outline.

As a result of intensive studies to solve the conventional drawbacks, it was found that an ink having a specific composition can achieve the above object, and the present invention has been completed.
That is, the present invention comprises the following 1 to 14.

1. (1) Pearl pigments and metal powder pigments, (2) water, (3) at least one water-soluble organic solvent such as alcohols, glycols and glycol ethers having a branched hydrophobic group, and (4) water-soluble dyes A high-gloss dual color ink composition comprising:
2. The high gloss dual color ink composition according to item 1, further comprising a water-soluble resin.
3. Item 3. The high gloss dual color ink composition according to Item 1 or 2, wherein the pearl pigment is metal oxide-coated mica.
4). Item 4. The high gloss dual color ink composition according to items 1 to 3, wherein the metal powder pigment is an aluminum pigment.
5. The weight ratio of the pearl pigment to the metal powder pigment is 0.1 to 5 metal powder pigment with respect to the pearl pigment 10, and the total content of pearl pigment and metal powder pigment is 4 to 20% by weight (as solid content). The high gloss dual color ink composition according to any one of Items 1 to 4.
6). 6. The high gloss dual color ink composition according to any one of items 1 to 5, wherein the water-soluble organic solvent is an alcohol represented by the general formula CnH2n + 2O (n: an integer of 4 to 6).
7). The high-gloss dual color ink composition according to any one of Items 1 to 5, wherein the water-soluble organic solvent is at least one of dipropylene glycol monopropyl ether, dipropylene glycol monomethyl ether and hexylene glycol.
8). Item 8. The water-soluble dye according to any one of Items 1 to 7, wherein the water-soluble dye is at least one of an anthraquinone dye, a diphenylmethane dye, a triphenylmethane dye, a xanthene dye, an acridine dye, and a metal complex dye. High gloss dual color ink composition.
9. The high gloss dual color ink composition for water-based ballpoint pens according to any one of Items 1 to 8.
10. ELD viscometer 3 ° (R14) cone The high gloss dual color ink composition for water-based ballpoint pens according to item 9, wherein the ink viscosity is 1000 to 10000 mPa · s when measured at 0.5 rpm (20 ° C).
11. A writing instrument using the composition according to any one of Items 1 to 10 as an ink.
12 A water-based ballpoint pen using the composition according to item 9 or 10 as an ink.
13. 13. The water-based ballpoint pen according to item 12, wherein a tip having a difference between a ball diameter and a ball house inner diameter of the ballpoint pen tip is 0.03 mm or more.
14 Color development characterized in that the pearl pigment and the metal powder pigment are removed by rubbing at least part of the handwriting drawn on the absorption surface using the ink composition according to any one of Items 1 to 10 with an eraser Method.

  The eraser is not particularly limited, and any commercially available product can be used. Further, the type (material) of the absorbing surface is not limited and can be applied to any type of absorbing surface as long as the effect of the present invention is obtained. For example, papers, fiber / wood materials, cloths and the like can be mentioned.

  The high-gloss dual color ink composition of the present invention and a writing instrument using the same are excellent in gloss and stable high-gloss double color without affecting the original color of the pearl pigment due to the color of the contour line. An effect can be obtained. Further, according to the ink composition of the present invention, even when the water-based ink is thickened, the colorant can be sufficiently permeated and diffused into the writing surface to form an effective contour line, and an excellent double color development effect is obtained. be able to.

  The high gloss dual color ink composition of the present invention can be used as an ink for various writing instruments, and is particularly suitable as an ink for water-based ballpoint pens. Further, if a ballpoint pen tip having a specific structure is employed in the water-based ballpoint pen of the present invention, the optimum ink outflow can be ensured, and as a result, the double coloring effect of the ink composition of the present invention can be obtained more reliably.

1. High gloss dual color ink composition The high gloss dual color ink composition of the present invention comprises (1) a pearl pigment and a metal powder pigment, (2) water, (3) an alcohol having a branched hydrophobic group, glycol And at least one water-soluble organic solvent of glycol ethers and (4) a water-soluble dye.

-Pearl pigment The pearl pigment is not particularly limited as long as it has excellent luster, and natural mica having a low refractive index, a surface of synthetic mica coated with a metal oxide having a high refractive index, fish scale foil, There are basic carbonates and bismuth oxychloride, but generally, natural mica or synthetic mica coated with a metal oxide is preferable. Since pearl pigments are glossy due to regular multiple reflection on parallel surfaces having different refractive indexes, the glossiness becomes weak when the particle diameter is smaller than 5 μm. Accordingly, the particle diameter is preferably 5 μm or more. Commercially available pearl pigments include Iriodin 100 (particle size 10-60 μm, silver color), Iriodin 103 (10-50 μm, silver color), Iriodin 300 (10-60 μm, gold color), Iriodin 302 (5-20 μm, gold color). ), Iriodin 323 (5 to 20 μm, gold), Iriodin 504 (10 to 60 μm, red), Iriodin 524 (5 to 20 μm, red), Iriodin 502 (10 to 60 μm, bronze), Iriodin 520 (5 to 20 μm, (Bronze color) (above, manufactured by Merck Japan), ULTIMICA SB-100 (5-30 μm, silver color), ULTIMICA SD-100 (10-60 μm, silver color), ULTIMICA RYB-100 (5-30 μm, gold), ULTIMICA RYD-100 (10-60 μm, gold) (Nippon Koken Kogyo Co., Ltd.), TAYCA PEARL TP-500 (10-70 μm, silver), TAYCA PEARL There is TPX-720 (7-45 μm, silver color) (manufactured by Teika). Pearl pigments can be used alone or in combination of two or more.

Metal powder pigment The metal powder pigment is not particularly limited as long as it has a metallic luster, and examples thereof include aluminum pigments and brass pigments. Examples of the aluminum pigment include “Alpaste WJP-U75C”, “Alpaste WE1200”, “Alpaste WXM7675”, “Alpaste WXM0630” (above, manufactured by Toyo Aluminum), “1110W”, “2172SW” (above, Showa Aluminum), “AW-808C”, “AW7000R” (manufactured by Asahi Kasei) and the like. Examples of brass pigments include “BS-605”, “BS-607” (above, manufactured by Toyo Aluminum Co., Ltd.), “Bronze Powder P-555”, “Bronze Powder P-777” (above, manufactured by Nakajima Metal Foil Powder Industry). ) And the like. Colored aluminum pigments such as “F500RG-W”, “F500BG-W”, “F701GR-W”, “F701RE-W” (above, Showa Aluminum) can also be used. These can be used alone or in combination of two or more. In addition, the particle size of a metal powder pigment can be suitably selected according to the designability of handwriting.

  Among these metal powder pigments, those subjected to water resistance treatment are preferable. The water resistance treatment can be performed by a known method. For example, a pigment treated with a phosphoric acid-containing solution can be used, and a commercially available product can also be used. Examples of commercially available products include “Alpaste WXM0630” (manufactured by Toyo Aluminum), “AW7000R” (manufactured by Asahi Kasei) and the like.

  The weight ratio between the pearl pigment and the metal powder pigment can be appropriately determined according to the desired design properties, the type of the pigment used, and the like. Yes, and more preferably 0.2 to 3 metal powder pigment relative to the pearl pigment 10. When the usage ratio of the metal powder pigment is 5 or more, the original high glossiness of the pearl pigment cannot be obtained. On the other hand, if it is less than 0.1, the concealing effect of the metal powder pigment is not sufficiently exhibited, so it is easily affected by the color of the contour line, and even if the same pearl pigment is used, it looks a completely different color depending on the color of the contour line. There is a risk that a malfunction will occur. Therefore, in the present invention, the weight ratio between the pearl pigment and the metal powder pigment is preferably 0.1 to 5 with respect to the pearl pigment 10.

  The total content of the pearl pigment and the metal powder pigment can be appropriately determined according to the type of the pigment used and the like, but is preferably 4 to 20% by weight, more preferably 5 to 5% as a solid content in the ink composition of the present invention. 15% by weight. If the content exceeds 15% by weight, the solid content concentration in the ink becomes high, which may adversely affect the viscosity, fluidity and the like. On the other hand, if it is less than 4% by weight, the hiding property by the pigment becomes insufficient, and there is a possibility that the double coloring effect cannot be obtained. Therefore, in the present invention, the total content of the pearl pigment and the metal powder pigment may be about 4 to 20% by weight.

Water-soluble organic solvent As the water-soluble organic solvent, at least one of alcohols, glycols and glycol ethers having a branched hydrophobic group is used.
The “having branched hydrophobic group” structure in the water-soluble organic solvent of the present invention means a structure in which a hydrophobic group is bonded to the main chain as a side chain in a chain compound. The kind of the hydrophobic group may be any of methyl group, ethyl group and the like. One or more hydrophobic groups may be present in the molecule, and when two or more hydrophobic groups are present, they may be the same or different from each other.

  Among the water-soluble organic solvents, alcohols having a branched hydrophobic group include, in particular, compounds represented by the general formula CnH2n + 2O (n: an integer of 4 to 6) such as isobutanol, s-butanol, t -Butanol (C4), isopentanol, s-pentanol, t-pentanol, 3-pentanol, 3-methyl-2-butanol, 2-methyl-1-butanol (C5), 2-ethylbutanol, 4 -Methyl-2-pentanol (C6) and the like.

  Examples of glycols and glycol ethers having a branched hydrophobic group include 1,3-octylene glycol, hexylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, poly (oxyethylene-oxypropylene) derivatives, Examples include ethylene glycol monoisopropyl ether, propylene glycol monobutyl ether, propylene glycol monoethyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol monomethyl ether. Among these water-soluble organic solvents, dipropylene glycol monopropyl ether, dipropylene glycol monomethyl ether, hexylene glycol and the like can be preferably used.

  The content of the water-soluble organic solvent can be appropriately determined according to the type of the water-soluble organic solvent, but is usually about 1 to 50% by weight, preferably 5 to 30% by weight in the ink composition of the present invention. . When the content of the water-soluble organic solvent exceeds 50% by weight, the solubility of the water-soluble resin may be reduced and may precipitate. When the content of the water-soluble organic solvent is less than 1% by weight, sufficient osmotic diffusion may not be obtained.

-Water-soluble dyes As water-soluble dyes, in the present invention, anthraquinone dyes, diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, acridine dyes, 1: 1 type metal complex dyes, and 1: 2 type metal complex dyes And at least one selected from copper phthalocyanine dyes can be used. As these dyes themselves, known ones or commercially available products can be used as they are. In the present invention, among these dyes, it is preferable to use at least one of a carbonium dye and a metal complex dye.

  The anthraquinone dye may be any one having an anthraquinone skeleton, and includes an anthraquinone derivative and an anthrone derivative. For example, use CIAcid Blue 27, CIAcid Blue 43, CIAcid Green 25, CIBasic Violet 25, CIBasic Blue 60, CIMordnt Red 11, CIAcid Red 83, CIDirect Green 28, CIMordant Blue 48, etc. Can do.

Examples of diphenylmethane dyes include CI Basic Yellow 2, CI Basic Yellow 3, CI Basic Yellow 37 and the like.
Triphenylmethane dyes include CIAcid Blue 90, CIAcid Blue 104, CIAcid Green 16, CIAcid Violet 49, CIBasic Red 9, CIBasic Blue 7, CIAcid Violet 1, CIAcid Red 289, CIDirect Blue 41, CIMordnt Blue 1, CIMordnt Violet 1 Etc. can be used.

  As the xanthene dye, C.I.Acid Yellow 73, C.I.Acid Yellow 74, C.I.Acid Red 52, C.I.Acid Violet 30, C.I.Basic Red 1, C.I.Basic Violet 10, C.I.Mordnt Red 27, C.I.Mordnt Violet 25 and the like can be used.

  Examples of acridine dyes include C.I.Basic Yellow 6, C.I.Basic Yellow 7, C.I.Basic Orange 14, C.I.Basic Orange 15, and the like.

  Examples of the metal complex dye include a metal complex dye, a dye containing a metal, and a dye capable of coordinating with a metal. For example, an azo dye having an OH group, a COOH group, an NH2 group, or the like can be used as a dye that can coordinate with a metal. As such azo dyes, for example, C.I.Mordant Red 30, C.I.Mordant Yellow 3, C.I.Mordant Green 15, C.I.Mordant Blue 13 and the like can be used.

  Among these metal complex dyes, copper phthalocyanine dyes, 1: 1 type metal complex dyes, 1: 2 type metal complex dyes, and the like can be preferably used. Specifically, CIDirect Blue 86, etc. as copper phthalocyanine dyes, CIAcid Yellow 54, CIAcid Orange 74, CIAcid Red 186, CIAcid Violet 56, etc. as 1: 1 type metal complex dyes, 1: 2 Examples of the type metal complex dye include CIAcid Yellow 59, CIAcid Black 60, CIAcid Red 296, CIAcid Blue 167 and the like.

  The content of the water-soluble dye can be appropriately determined according to the type of the water-soluble dye, etc., but is usually about 0.05 to 5% by weight, preferably 0.1 to 3% by weight in the ink composition of the present invention. What should I do? If the water-soluble dye exceeds 5% by weight, the viscosity and fluidity may be adversely affected. If the water-soluble dye is less than 0.05% by weight, the desired double color development effect may not be obtained.

-Water-soluble resin etc. In this invention, a water-soluble resin can also be mix | blended as needed. The water-soluble resin is not particularly limited as long as it can impart thickening and / or adhesiveness to the water-based ink, and can be appropriately selected according to the purpose of use. For example, microbial polysaccharides or derivatives thereof such as pullulan, xanthan gum, welan gum, and lamb gum gum; water-soluble plant polysaccharides or derivatives thereof, guar gum, locust bean gum, pectin; water-soluble animal polysaccharides or derivatives thereof as gelatin; Casein and the like; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose (CMC), and sodium salts and ammonium salts of celluloses such as hydroxypropyl cellulose; starchy derivatives such as starch, cationic starch, dextrin, modified dextrin, and sodium starch glycolate; Polyvinyl alcohol (PVA), polyvinyl pyrrolidone, polyvinyl ether, etc. as vinyl synthetic polymers; Um, carboxyvinyl polymers and the like; polyethylene oxide as other synthetic polymers, methoxy ethylene-maleic acid copolymer or the like can be used. These can be used alone or in combination of two or more.

  The content of the water-soluble resin can be appropriately determined according to the type of the water-soluble resin and the like, but is usually about 0.05 to 40% by weight, preferably 0.1 to 30% by weight in the ink composition of the present invention. What should I do? If the water-soluble resin exceeds 40% by weight, writing may be difficult. When the water-soluble resin is less than 0.05% by weight, the predetermined addition effect may not be obtained.

  In the ink composition of the present invention, other additives may be blended within a range that does not hinder the effect. For example, polyoxyethylene alkali metal salts, dicarboxylic acid amides, phosphate esters, N-oleyl sarcosine salts, etc. as lubricants; polyhydric alcohols or derivatives thereof (glycerin, etc.) as wetting agents; benzotriazoles, tolyltriazoles as rust inhibitors Dicyclohexylammonium nitrate and the like; benzoisothiazoline-based, pentachlorophenol-based, cresol and the like as antiseptic / rust-proofing agents, and various other dispersants and surfactants.

  The ink viscosity of the ink composition of the present invention is usually about 1000 to 10000 mPa · s when measured with an ELD viscometer 3 ° (R14) cone 0.5 rpm (20 ° C.) when used for an aqueous ballpoint pen. It is preferable. By setting the ink viscosity within this range, it is possible to obtain particularly excellent temporal stability and writing property as a water-based ballpoint pen. The ink viscosity can be adjusted with a water-soluble resin, water, or the like.

  The ink composition of the present invention can be prepared using a known dispersion method, defoaming method, filtration method and the like. For example, it can be obtained by mixing and stirring water, a water-soluble dye and a metal powder pigment, blending a water-soluble resin, and then blending a water-soluble organic solvent and various additives as required. In addition, what is necessary is just to use well-known stirring apparatuses, such as a dissolver, a mixer, a kneader, for the mixing or stirring in each process.

2. Writing Instruments The ink composition of the present invention can be used as ink for various writing instruments, and can be used as, for example, a marker, a sign pen, a ballpoint pen, etc., but can be suitably used particularly as an aqueous ballpoint pen ink. In the writing instrument of the present invention, constituent members of known writing instruments (markers, water-based ballpoint pens, etc.) can be appropriately employed in terms of points other than ink.
In the case of a water-based ballpoint pen, for example, ink containing tubes having a known material and size can be applied as they are. As the material, for example, synthetic resin pipes such as polyethylene and polypropylene, and other metal pipes can be used. The ballpoint pen may be assembled according to a known ballpoint pen assembly method.

  Further, the same material and structure as those used in known water-based ballpoint pens can be used for the ballpoint pen tip, but the difference between the ball diameter and the ball house inner diameter is usually 0.03 mm or more, particularly 0.03 to 0. It is preferable for the ink composition of the present invention (the writing instrument of the present invention) to use a ballpoint pen tip of 0.07 mm. In the present invention, the difference corresponds to the distance at the point where the distance between the ball and the inner surface of the ball house is closest. The difference between the ball diameter and the ball house inner diameter in a conventional ballpoint pen (ballpoint pen tip) is usually about 0.01 to 0.02 mm, but in the present invention, the ink of the present invention is provided by providing a large difference of 0.03 mm or more. A good double color developing effect by the composition can be obtained more reliably.

3. Coloring Method The present invention also includes a coloring method characterized in that the pearl pigment and the metal powder pigment are removed by rubbing at least part of the handwriting drawn on the absorption surface using the ink composition of the present invention with an eraser.

  When the handwriting by the ink composition of the present invention is rubbed with an eraser, only the surfaces of the pearl pigment and the metal powder pigment are substantially removed, and only the dye surface remains on the absorption surface. As a result, the covered dye surface is exposed, and as a result, a color of only the dye can be obtained. For example, when only a part of the handwriting is rubbed with an eraser, it is possible to create a variety of appearances consisting of a combination of double coloration and dye-only coloration, making it possible to create various designs.

  When the handwriting by the ink composition of the present invention is rubbed with an eraser, the pearl pigment and the metal powder pigment are substantially removed. As a result, it is possible to easily obtain a color by using only the dye and to create various designs. .

  The features of the present invention will be described more specifically with reference to the following examples and comparative examples. However, the present invention is not limited to these. Table 1 shows the compositions of Comparative Objects A to C, Examples 1 to 7, and Comparative Examples 1 to 4. Each ink having the composition (% by weight) shown in Table 1 was prepared by stirring for 2 hours using a desper at room temperature.

Each component shown in Table 1 is as follows.
(1) Pearl pigment / Pearl pigment 1: Metal oxide-coated mica ("Iriodin 323" manufactured by Merck)
Pearl pigment 2: Mica coated with metal oxide (“Iriodin 520” manufactured by Merck)
(2) Metal powder pigment / Metal powder pigment 1: Aluminum powder pigment ("Alpaste WXM0630" manufactured by Toyo Aluminum)
Metal powder pigment 2: Aluminum powder pigment ("AW7000R" manufactured by Asahi Kasei)
(3) Water-soluble organic solvent / Water-soluble organic solvent 1: Dipropylene glycol monomethyl ether (reagent)
・ Water-soluble organic solvent 2: Dipropylene glycol monopropyl ether (reagent)
(4) Water-soluble resin / Water-soluble resin 1: Ramzan gum ("K7C233" made by Sanki)
Water-soluble resin 2: PVA (manufactured by “PVA-204” Kuraray)
(5) Water-soluble dyes / Water-soluble dyes 1: Acid Red 289
Water-soluble dye 2: Acid Green 16
Water-soluble dye 3: Acid Blue 104
(6) Additives / Preservatives: ("Proxel XL-2" manufactured by Solusia)
・ Anti-mold agent: ("Coat Side H" manufactured by Takeda Pharmaceutical)

  As described above, each of the ink compositions of Comparative Examples A to C, Examples 1 to 7 and Comparative Examples 1 to 4 shown in Table 1 is attached to a polypropylene ink containing tube having a stainless ballpoint pen tip (ball material: ceramics) attached to one end. Filled and filled with an ink backflow preventive (gelled silicone oil) to prepare a ballpoint pen refill. Next, a ballpoint pen refill was attached to the main body, a cap was attached, air in the tube was removed by a centrifuge, and finally a tail plug was attached to obtain a ballpoint pen.

Then, the handwriting of the ballpoint pen filled with the ink prepared as a comparison object (ink not containing the dye for obtaining the contour line) and the handwriting of the ballpoint pen prepared in the example and the comparative example were compared, and the following criteria were used. evaluated. The evaluation results are shown in Table 1.
○: The color of the pearl color part looks the same color as the comparison target.
X: The color of the pearl color part is influenced by the color of the outline, and looks different from the comparison target.
In Comparative Examples 1 to 4, the color of the pearl color part was influenced by the color of the outline, and looked different from the comparison target. Even when the comparative example 1 and the comparative example 2 were compared, although the compositions other than the water-soluble dye were the same, they looked different pearl colors.

  On the other hand, in Examples 1-7, the color of the pearl color part looked the same color as the comparison object. Therefore, even when the composition other than the water-soluble dye is made the same and the water-soluble dye has a different color, a stable pearl color can be obtained without being affected by the color of the contour line. When these handwritings were rubbed with a commercially available eraser, the pearl pigment and metal powder pigment were removed, and lines with water-soluble dyes appeared clearly.

As is clear from these results, the ink of the present invention is a dual color ink composition that can achieve stable pearl color development without being affected by the color of the contour line.

Claims (14)

(1) Pearl pigments and metal powder pigments, (2) water, (3) at least one water-soluble organic solvent such as alcohols, glycols and glycol ethers having a branched hydrophobic group, and (4) water-soluble dyes A high-gloss dual color ink composition comprising: The high gloss dual color ink composition according to claim 1, further comprising a water-soluble resin. The high gloss dual color ink composition according to claim 1 or 2, wherein the pearl pigment is a metal oxide-coated mica. The high gloss dual color ink composition according to claim 1, wherein the metal powder pigment is an aluminum pigment. The weight ratio of the pearl pigment to the metal powder pigment is 0.1 to 5 metal powder pigment with respect to the pearl pigment 10, and the total content of pearl pigment and metal powder pigment is 4 to 20% by weight (as solid content). The high gloss dual color ink composition according to any one of claims 1 to 4. 6. The high gloss dual color ink composition according to claim 1, wherein the water-soluble organic solvent is an alcohol represented by the general formula CnH2n + 2O (n: an integer of 4 to 6). The high-gloss dual color ink composition according to any one of claims 1 to 5, wherein the water-soluble organic solvent is at least one of dipropylene glycol monopropyl ether, dipropylene glycol monomethyl ether and hexylene glycol. The high-gloss property according to any one of claims 1 to 7, wherein the water-soluble dye is at least one of an anthraquinone dye, a diphenylmethane dye, a triphenylmethane dye, a xanthene dye, an acridine dye, and a metal complex dye. Double color ink composition.  The high gloss dual color ink composition for water-based ballpoint pens according to any one of claims 1 to 8. The high gloss dual color ink composition for water-based ballpoint pens according to claim 9, wherein the ink viscosity is 1000 to 10000 mPa · s when measured at ELD viscometer 3 ° (R14) cone 0.5 rpm (20 ° C). A writing instrument using the composition according to claim 1 as an ink. An aqueous ballpoint pen using the composition according to claim 9 or 10 as an ink. The water-based ballpoint pen according to claim 12, wherein a tip having a difference between a ball diameter and a ball house inner diameter of the ballpoint pen tip is 0.03 mm or more. A coloring method comprising removing the pearl pigment and the metal powder pigment by rubbing at least a part of the handwriting drawn on the absorption surface with the eraser using the ink composition according to claim 1.