JPH09249844A - Water-based metallic luster color ink composition for ball point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water-based metallic luster color ink composition which comprises a specific pigment, a substance as a dispersant and a thickener, a humectant, cyclodextrin and water as essential components and is useful for ball point pens, because it is excellent in pigment dispersion stability, prevention of ink adhesion to an ink-containing tube and prevention of sedimentation of coloring pigments into porous paper. SOLUTION: As essential components, contains (A) an aluminum powder pigment, (B) a polysaccharide such as xanthan gum, guaiac gum, succinoglycan, Locust bean gum, as a dispersant and a thickener, (C) cyclodextrin, (D) a humectant of hard volatile, water-soluble organic solvent such as a low molecular- weight polyethylene glycol, glycerol, N-methyl-pyrrolidone and (E) water, when necessary, (F) a coloring pigment. In a preferred embodiment, this ink composition contains components A, B and F in amounts of 1-10wt.% 0.5-10wt.% and 0.5-25wt.%, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-based metallic luster color ink composition for ballpoint pens, and more particularly, it is a type in which ink is stored in a free state in a barrel having a ballpoint pen tip at the tip. A water-based metallic gloss color applied to a ballpoint pen with a simple structure that does not require a complicated mechanism (commonly called a pen core) for adjusting the ink flow rate and the exchange of ink and air between the ink storage parts. It relates to an ink composition.

[0002]

2. Description of the Related Art Several proposals have been made in the past for inks of this type (for example, JP-A-6-313).
No. 142, inventions described in JP-A No. 7-145339, etc.), all of them have a problem that sedimentation of the metal powder pigment in the ink always occurs over time. In addition, a ball-point pen using this type of ink is usually made of a hydrophobic plastic pipe such as polyethylene or polypropylene as an ink containing pipe because of its transparency (visual confirmation of remaining ink amount) and low unit price. However, since the aluminum powder pigment in the ink is an aluminum powder surface-treated with a fatty acid, it easily adheres to the wall surface of the hydrophobic plastic pipe.
With inks using general colorants, as the ink is consumed by using a ballpoint pen, the ink moves toward the pen tip without adhering to the wall surface of the pipe, and the rear end surface of the ink column becomes clear and the remaining ink amount becomes clear. . However,
In the case of metallic gloss color ink, even if the ink is consumed for the above reason, the ink adheres to and remains on the wall surface of the pipe, so that the trailing end of the ink is unclear, the appearance is poor, and the remaining ink amount cannot be accurately determined. Furthermore, in the case of an ink in which a coloring pigment is used in combination with an aluminum powder pigment, the handwriting written on porous paper is such that the coloring pigment with relatively fine particles selectively sinks into the fibers of the paper and the hue of the coloring pigment changes. Is not exhibited, and there is a tendency that a phenomenon occurs in which only the silver color of the aluminum powder pigment remaining in the upper layer exhibits a color tone emphasized.

[0003]

SUMMARY OF THE INVENTION The present invention is directed to the problem of settling of aluminum powder pigments with the passage of time, and to the unclearness of the rear end of the ink column due to the adhesion of aluminum powder pigments on the wall surface of the ink containing tube as the ink is consumed. Water-based ballpoint pen that solves all the problems and problems of combined use of aluminum pigment and coloring pigment that the metallic color tone is not colored well due to the sinking of the coloring pigment on the porous paper surface inside the paper fiber. It is intended to provide a metallic luster color ink composition.

[0004]

A water-based metallic luster color ink composition for ballpoint pens according to the present invention comprises (a) an aluminum powder pigment, (b) a dispersant / thickener selected from polysaccharides, and (iii) ) A composition containing cyclodextrin, a moisturizer selected from (d) a sparingly volatile water-soluble organic solvent, and (e) water. The components used will be described below.

Aluminum powder pigments include a leafing type consisting of an aluminum powder whose surface is treated with a saturated higher fatty acid and a non-leafing type consisting of an aluminum powder treated with an unsaturated fatty acid. The leafing type is suitable for ink that gives handwriting, and the non-leafing type is easier to mix with the coloring pigment in the ink that is used together with the coloring pigment to give the handwriting of colored metallic tone, and the lower layer than the coloring pigment when forming the handwriting. It is preferably used because it has a tendency to form. These aluminum powder pigments are supplied in the form of a paste which is wet with a hydrocarbon solvent such as mineral terpene or a glycol ether solvent such as propylene glycol monomethyl ether, but is preferably 1 to 10% by weight in terms of aluminum powder in the ink composition, preferably Is 2 to 7% by weight
Used in the range. If the amount used is less than the above range, sufficient metallic glossy handwriting cannot be obtained, and if too much amount is used, it becomes difficult to maintain stable dispersion in the medium, and if it is attempted to stabilize the dispersion, the viscosity of the medium increases. Have to let
As a result, ink outflow from the pen body of the marking pen is hindered.

Coloring pigments added in addition to aluminum powder pigments to provide metallic color handwriting include C.I. I. Pigment Yellow 1, 3, 12, 65,
74, 83, 93, 120, 154, C.I. I. Pigment Orange 17, 36, 40, C.I. I. Pigment Red 1, 2, 5, 9, 49, 53, 144, 190, C.I.
I. Pigment Green 7, 36, C.I. I. Pigment Blue 15 and the like, and fluorescent pigments obtained by dyeing resin particles of an acrylic resin emulsion with a dye. These coloring pigments are contained in the ink composition in an amount of 0.5 to 25% by weight,
It is preferably used in the range of 1 to 20% by weight. When the amount used is out of the above range, the balance with the silver color of the aluminum powder pigment cannot be achieved, and a preferable metallic color tone cannot be obtained.

The pigments are dispersed in an aqueous medium with one or more polysaccharides selected from xanthan gum, guar gum, succinoglycan, locust bean gum, carrageenan gum, welan gum, rhamzan, pectin, alginic acid derivatives and the like. To be done. These polysaccharides are used in the range of 0.1 to 1% by weight in the ink composition, and the addition amount within this range imparts appropriate viscosity and thixotropy to the ink and maintains the dispersion stability of the pigment particles. As the dispersant, a surfactant selected from anionic surfactants and nonionic surfactants may be used in combination.

Next, cyclodextrin and its action will be described. As described above, the aluminum powder pigment used is surface hydrophobic because the aluminum powder surface is treated with a higher fatty acid and the long carbon chain of the fatty acid covers the particle surface, but an ink containing cyclodextrin has been added. Cyclodextrin wraps the pigment particles therein, modifying the hydrophobic surface of the pigment particles to a hydrophilic surface. As a result, the pigment particles have an affinity for an aqueous medium to improve dispersion stability in the aqueous medium,
Almost no pigment adheres to the wall surface of the ink containing tube made of hydrophobic plastic, and the rear end of the ink column can be transferred smoothly due to ink consumption when using the ballpoint pen. Furthermore, in an ink of a system in which an aluminum powder pigment and a coloring pigment are used in combination, even when written on porous paper, the coloring pigment wrapped with cyclodextrin suppresses the sinking into the paper fiber, It has the same standard metallic color as paper. The cyclodextrin used may be any one of α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, and maltosyl cyclodextrin, which is in the range of 0.5 to 10% by weight, preferably 2 to 7% by weight in the ink composition. Used in. If the amount added is less than the above range, a sufficient effect cannot be obtained, and if the amount added exceeds 10% by weight, no further effect is obtained.

Further, a water-soluble resin or a resin emulsion may be used as a fixing agent for fixing the handwriting to the target surface well. As the water-soluble resin, high molecular weight polyethylene glycol, polyvinylpyrrolidone, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose and the like are used, and as the resin emulsion, an acrylic resin emulsion, a urethane resin emulsion, a vinyl acetate resin emulsion, An ethylene / vinyl acetate copolymer emulsion or the like is used. These are used in the ink composition in a range of 0.01 to 10% by weight as a solid content.

In order to allow immediate writing even after a long period of non-use in a ballpoint pen or after the cap is removed and the pen tip is exposed, the evaporation of water in the ink at the pen tip is suppressed. The medium is ethylene glycol, propylene glycol, diethylene glycol, liquid low molecular weight polyethylene glycol, glycerin, 2
Moisturizers selected from sparingly volatile water-soluble organic solvents such as -pyrrolidone and N-methylpyrrolidone are added. These moisturizers are used in the range of 5 to 30% by weight in the ink composition. In addition, lubricants (phosphate ester, fluorine-based surfactants, silicone-based surfactants), preservatives, etc.
A small amount of antifungal agent, rust preventive agent, pH adjusting agent and the like are added.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The ink of the present invention is prepared according to the following steps. (1) Pour water, a moisturizer and cyclodextrin into a container, stir and dissolve into an aqueous solution obtained (2) Add resin, color pigment and other additives to be added, stir and mix To do. (3) Next, an aqueous paste of polysaccharide prepared in advance is added and mixed. (4) Finally, the mixture to which the aluminum powder pigment paste previously mixed with water in a ratio of 1: 1 is added is thoroughly mixed by a disper until it becomes homogeneous. A comparative ink used in the comparative test described below was also prepared according to the above process. However, cyclodextrin was not added in the above step, whereby steps (1) and (2) were started in a combined step, and then the above step order was followed.

[0012]

EXAMPLES Table 1 shows the composition and physical properties of the example inks and the comparative example inks. All the numerical values of the compositions in the table represent parts by weight. Each sample ink was prepared by the above manufacturing method.

[Table 1]

The contents of the raw materials and the physical properties of the sample ink in the table will be described along with the note numbers. (1) "Alpaste WXM" manufactured by Toyo Aluminum Co., Ltd.
0650 "(heating residue 62% by weight) (2)" AW-7000R "manufactured by Asahi Kasei Metals Co., Ltd.
(Heating residue 63% by weight, average particle diameter 15 μm) (3) “Alpaste WB0” manufactured by Toyo Aluminum Co., Ltd.
230 "(65% by weight of aluminum powder, 30% by weight of mineral terpene, 5% by weight of stearic acid dimer acid) (4)" Iso Elite P "manufactured by Saltwater Port Sugar Co., Ltd. (total cyclodextrin amount 80% or more, maltosyl cyclo (Dextrin amount 70% or more) (5) "Dixie Pearl K-10" manufactured by Shimizu Port Sugar Co., Ltd.
0 "(total cyclodextrin amount 98% or more, α-cyclodextrin amount 70% or more) (6) Saltwater Port Sugar Co., Ltd." Iso Elite L "(total cyclodextrin amount 80% or more, maltosyl cyclodextrin amount (70% or more, solid content 70% or more) (7) 2% aqueous dispersion of Sanyo Co., Ltd. "Reozan" (succinoglycan) (8) 2 of "Kelcogel" (xanthan gum) manufactured by Dainippon Pharmaceutical Co., Ltd. % Aqueous dispersion (9) "PEO-18" manufactured by Sumitomo Seika Chemicals Ltd. (molecular weight 43
2% aqueous solution of 0,000 to 4,800,000 polyethylene glycol) (10) Styrene / acrylic ester copolymer emulsion (nonvolatile content 41%, pH 7.6, viscosity 300 mPas)
・ S) (11) "Sandai Yellow R-P" manufactured by Sanyo Dye Co., Ltd.
(CI Pigment Yellow 13 16.5%, anionic surfactant 2.8%) (12) "Sandai Super Blue GL" manufactured by Sanyo Dye Co., Ltd.
L "(CI Higment Blue 15: 3 21%, nonionic surfactant 5.5%) (13)" WS Green G1-P "manufactured by Toyo Ink Co., Ltd.
(Aqueous dispersion of phthalocyanine green pigment with 32% surfactant) (14) "Sandai Super Yellow G" manufactured by Sanyo Dye Co., Ltd.
SN "(CI Higment Yellow 14 18%, nonionic surfactant 7.5%) (15) Zeneka" Proxel XL2 "(16) 1 rpm (rotation by EM type viscometer (Tokyo Keiki)) / Min) and viscosity values η ₁ and η measured at 100 rpm
₁₀₀ (Unit: mPa · s, temperature: about 20 ℃) (17) Color tone of lines drawn on writing paper A (JIS P3201) (standard tone) "Yellow silver" is metallic yellow, "Blue silver" is metallic blue, ""Greensilver" represents the color tone of metallic green.

Next, the following tests were conducted on the sample inks, and the results are summarized in Table 2.

[Table 2] (1) Pigment Settling Acceleration Test 10 g of each sample ink was placed in a test tube having an inner diameter of 14 mm and a length of 105 mm, and 3000 rpm (187
It was centrifuged for 3 minutes (corresponding to 0 G) and the presence or absence of sediment at the bottom of the test tube was observed. (2) Color Sink of Colored Pigment The color tone of handwriting on a porous paper (black Kent paper) surface was observed with a sample pen (a construction and a method of which will be described later). Evaluation symbol ○: Substantially the same as the standard color tone ×: Almost no coloration of the blended color pigment (3) Ink adhesion stains The rear end of the ink column of the sample pen and the ink follower (liquid stopper) The presence or absence of ink adhesion stains on the inner wall surface of the pipe at the interface part of was observed. Evaluation symbol ○: Clearly visible interface with no ink adhesion stain ◇: Very little ink adhesion stain and almost visible interface △: Invisible interface due to ink adhesion stain x: Ink adhesion stain Therefore, the interface cannot be identified at all

In the sample pen, each sample ink is filled in an ink containing tube made of a polypropylene pipe, and a ball-point pen tip is inserted into one end of the pipe to prevent ink from leaking out from the other end. Inject the grease-like transparent ink follower (liquid stopper) and centrifuge it so that the ink fills the pen tip without any gap (1000G / 1
Minutes).

[0016]

INDUSTRIAL APPLICABILITY The water-based metallic luster color ink composition for ball-point pens of the present invention is prepared by encapsulating particles of an aluminum powder pigment or a coloring pigment in which cyclodextrin originally has a hydrophobic surface in the ink and modifying it to a hydrophilic surface. Due to the action that is thought to increase the affinity for the aqueous medium, not only the effect of significantly improving the pigment dispersion stability of the ink is exhibited, but also ink adhesion stains on the wall surface of the ink container made of hydrophobic plastic are eliminated. The appearance of the ballpoint pen and the position of the rear end of the ink column that shifts as the ink is consumed are clarified (the remaining ink amount is confirmed), and the metallic color is suppressed by suppressing the color sinking phenomenon of the colored pigment in the handwriting on the porous paper surface. It has various effects of maintaining the beautiful color tone of.

Claims (3)

[Claims] 1. A dispersant / thickener selected from (a) an aluminum powder pigment and (b) a polysaccharide, as essential components,
(C) A water-based metallic luster color ink composition for ball-point pens, which contains cyclodextrin, (D) a moisturizer selected from sparingly volatile water-soluble organic solvents, and (V) water. 2. A water-based metallic luster color ink composition for a ball-point pen according to claim 1, which contains 1 to 10% by weight (aluminum powder equivalent) of aluminum powder pigment and 0.5 to 10% by weight of cyclodextrin in the total ink composition. Stuff. 3. The water-based metallic luster color ink composition for a ball-point pen according to claim 1, further comprising 0.5 to 25% by weight of a color pigment in the total ink composition.