JP2003138194A - Water-based ink composition erasable with eraser, writing implement using the same and method of producing the rubber-erasable water-based ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-based ink composition erasable with eraser in which the handwriting written with the ink on the paper can readily be erased with eraser and resists peeling off with abrasion between paper sheets or with fingers and can retain the handwriting deeply and clearly with high stability. SOLUTION: The water-based ink composition contains capsule particles, water-soluble organic solvents and water. The capsule particles are composed of the surface layer in which a sticky polymer is used as at least a wall material for the capsules and of the core layer including inorganic or organic fine particles of 0.1-12 μm particle size distribution and coloring materials. In this case, the coloring materials are localized near the outer surface of the inorganic or organic fine particles. The capsule particles have the particle size distribution of 1-20 μm.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an eraser-erasable water-based ink composition and a writing instrument using the same.

[0002]

2. Description of the Related Art Conventionally, many proposals have been made for an eraser-erasable water-based ink composition. For example, JP-A-5
JP-A-279614 discloses "a resin having a film forming temperature of 0 ° C. or lower or a glass transition temperature of 0 ° C. or lower, a particle size of 1 to
An erasable ink containing 20 μm of colored spherical resin fine particles and water and having an ink viscosity of 5 to 35 mPa · sec ”is disclosed in JP-A-2001-19888. At least a part of the surface of the resin fine particles has adhesiveness, and the particle distribution of the particles is at least 70% by weight in the range of 2 μm to 20 μm. At least from the adhesive colored resin granules, water and a water-soluble polar solvent. "Erasable water-based ink composition for writing eraser". In the ink composition described in any of the publications, in order to have eraser erasability, the colorant is prevented from penetrating into the inside of the paper surface, and the colorant and the adhesive resin are added in order to impart the handwriting retention property. Ink composition is prepared using the colored resin fine particles of However, these ink compositions are inferior in darkness to a ball-point pen using a pigment itself as a coloring material because the coloring materials are scattered in the resin fine particles, and when erased with an eraser. Although the colored resin fine particles are aggregated and removed in agglomeration, the handwriting is not scraped off by rubbing the surface of the paper surface, so that the erasability of the colored resin particles is more difficult to erase than that of a pencil. Further, in terms of stability over time, there is a drawback that sedimentation of particles is likely to occur as compared with a ballpoint pen using a pigment itself as a coloring material.

[0003]

DISCLOSURE OF THE INVENTION As a result of intensive studies conducted by the present inventors in order to solve the above-mentioned problems of the prior art, as a result of using colored resin fine particles, it is difficult to obtain a thick resin. It is thought that this is because the coloring agent is scattered in the fine particles, and a technique for encapsulating inorganic or organic fine particles in the core of the colored resin fine particles and localizing the coloring material near the outer surface of the inorganic or organic fine particles is proposed. Heading, by this, even if using colored resin fine particles, it has a sufficient thickness as an ink composition for writing applications, and in the eraser erasability, the inorganic or organic fine particles scrape the handwriting by rubbing the paper surface. Therefore, it was found that the eraser has an excellent erasability, and further, the specific gravity with the dispersion medium is adjusted by using hollow fine particles or fine particles having a low specific gravity as the inorganic or organic fine particles. It has been found that it is possible to obtain stability over time, which has led to the completion of the present invention. The object of the present invention is to erase the eraser-erasable water-based ink composition and It is to provide a writing instrument using it.

[0004]

The gist of the present invention is an eraser-erasable water-based ink composition comprising capsule particles, a water-soluble organic solvent, and water, wherein the capsule particles have at least a part of their surface. Is a polymer having an adhesive property as a wall material, and internally includes a color material as a core substance and inorganic or organic fine particles having a particle size distribution of 0.1 μm to 12 μm, and the color material is an outer surface of the inorganic or organic fine particles. It is localized in the vicinity and the particle size distribution of the capsule particles is 1 μm.
It is an eraser-erasable water-based ink composition characterized by having a size of m to 20 μm. That is, in the present invention, the density of the ink composition is increased by encapsulating the inorganic or organic fine particles together with the coloring material in the capsule particles and localizing the coloring material near the outer surface of the inorganic or organic fine particles. By using a hard encapsulated fine particle,
The internal fine particles work to scrape the handwriting when erasing the handwriting with an eraser. Furthermore, by using inorganic or organic fine particles, the specific gravity with the dispersing medium is adjusted to obtain stability, and by these actions, It was possible to provide an eraser-erasable water-based ink composition having an ink strength, eraser-erasability and stability over time superior to those described above, and a writing instrument using the same.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail.
In the present invention, the wall material is a polymer in which at least a part of the surface of the capsule particles has adhesiveness. As such a polymer, one having a glass transition temperature of 60 ° C. or lower is preferable. A glass transition temperature of 60 ° C. or lower, preferably 30 ° C. to 45 ° C. gives the capsule particles proper tackiness and can be easily erased with a fixability and eraser that can withstand rubbing such as rubbing with fingers or paper surfaces. It may have possible erasability. If the particle size distribution of the capsule particles is smaller than 1 μm, it will enter into the space on the paper surface and it will be difficult to erase with an eraser. If it is larger than 20 μm, the ball holder portion called the tip of the ballpoint pen will be clogged. Therefore, it is important to meet the above requirements. The particle size distribution of the inorganic or organic fine particles to be encapsulated in the capsule particles is in the range of 0.1 to 12 μm.
If it is less than 0.1 μm, the merit of including the inorganic or organic fine particles, that is, the effect of the present invention, that is, the improvement of the density of the ink composition, the erasability of the eraser and the stability with time, cannot be seen so much. On the other hand, when it is larger than 12 μm, it becomes difficult to encapsulate inorganic or organic fine particles and obtain capsule particles having a desired size. The capsule particles containing the inorganic or organic fine particles and the coloring material are prepared by a suspension polymerization method. In the emulsion polymerization method or the mini-emulsion polymerization method, the size of the capsule particles themselves becomes small, and the particles enter the pores of the paper surface, making it difficult to erase. On the other hand, the suspension polymerization method, the seed polymerization method, the in-liquid drying method, the dispersion polymerization method and the like are relatively easy to obtain particles having a particle diameter suitable for the present invention. Among them, the suspension polymerization method is considered to be suitable for the present invention in terms of the size of the produced particles, the properties of the capsule particle wall, the strength and the like.

Therefore, the suspension polymerization method will be described below. The suspension polymerization method is a method in which a monomer phase in which a polymerization initiator is dissolved is dispersed in a droplet form in a continuous phase that is incompatible with this monomer phase to produce spherical polymer particles. . The suspension polymerization method of the present invention will be described in detail. An oil-soluble polymerization initiator, and a water-insoluble monomer in which inorganic or organic fine particles and a coloring material are dispersed or dissolved are contained in a dispersant called a suspension stabilizer. This is a method of producing a polymer capsule particle containing inorganic or organic fine particles and a coloring material by advancing the polymerization in a dispersion system in which oil droplets are dispersed in water. Therefore, the monomer used in the present invention is preferably a water-insoluble or sparingly soluble monomer,
Any radically polymerizable monomer can be used without limitation. Specific examples of such a monomer include polymerizable unsaturated aromatics such as styrene, chlorostyrene, α-methylstyrene, divinylbenzene and vinyltoluene,
Acrylic acid, methacrylic acid, itaconic acid, maleic acid,
Polymerizable unsaturated carboxylic acids such as fumaric acid, polymerizable unsaturated sulfonic acids such as sodium styrene sulfonate or salts thereof, methyl methacrylate, methyl acrylate, ethyl methacrylate, ethyl acrylate, n-butyl methacrylate, acrylic Acid n-butyl, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, glycidyl methacrylate, glycidyl acrylate, ethylene glycol dimethacrylate, ethylene glycol diacrylate, acrylonitrile, methacrylonitrile, methacrolein , Acrolein, methacrylamide, acrylamide, butadiene, isoprene, vinylpyridine, N-vinylpyrrolidone, conjugated dienes and the like. Various polyfunctional compounds or monomers can also be used as crosslinkers. Such examples include divinylbenzene, divinylnaphthalene, divinylcyclohexane, 1,3-dipropenylbenzene, ethylene glycol dimethacrylate,
Examples thereof include ethylene glycol diacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, butylene glycol, trimethylolethane triacrylate, trimethylolethane trimethacrylate, pentaerythritol tetramethacrylate, and pentaerythritol tetraacrylate.

The polymerization initiator is preferably a water-insoluble or sparingly soluble polymerization initiator, and any radical polymerization initiator can be used without limitation. 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylpropanenitrile), 2,2'-azobis- (2,4-dimethylpentanenitrile), 2,2'-azobis- (2-
Methylbutanenitrile), 1,1'-azobis- (cyclohexanecarbonitrile), 2,2'-azobis-
(2,4-dimethyl-4-methoxyvaleronitrile),
Azo (azobisnitrile) type initiators such as 2,2′-azobis- (2-aminodipropane) hydrochloride, benzoyl peroxide, cumene hydroperoxide, acetyl peroxide, hydrogen peroxide, lauroyl peroxide, peroxide Peroxide type initiators such as sulfates, (ammonium persulfate), peroxyesters (eg t-butyl peroctate, α-cumyl peroxypivalate and t-butyl peroctate) are mentioned.

The organic fine particles to be encapsulated in the capsule particles can also be prepared by the suspension polymerization method. The above water-insoluble or sparingly soluble monomer and a polymerization initiator soluble in the monomer are dissolved, and stirred and dispersed in water containing a suspension stabilizer at high speed to generate oil droplets, and radical polymerization is carried out at a temperature. It can be prepared by starting. At this time, it is possible to obtain hard organic particles or soft organic particles by appropriately selecting the type of the monomer, and the hardness of the core substance also affects the erasability. Alternatively, commercially available inorganic or organic fine particles may be used. Crosslinked polystyrene acrylic particles SX8703 and SX704 manufactured by JSR Corporation, crosslinked acrylic monodisperse particles MX series and crosslinked polystyrene particle SGP series manufactured by Soken Chemical Co., Ltd., and Godball E-manufactured by Suzuki Yushi Kogyo Co., Ltd. Porous silica spherical particles such as 2C and E-6C can be used, and in some cases it is preferable to perform classification. Any spherical particles having a particle diameter of 12 μm or less can be used without being limited to the above. The inorganic or organic fine particles may be hollow particles, and the specific gravity of the coloring material and the inorganic or organic fine particle-encapsulating capsule particles is used to match the specific gravity of the dispersion medium of the ink composition. It is possible to prevent sedimentation of capsule particles and improve stability over time.
The organic hollow fine particles can be similarly prepared by the suspension polymerization method, and the preparation method will be described below. The water-insoluble or sparingly soluble monomer and the polymerization initiator that is soluble in the monomer are dissolved, and a large amount of an oil-soluble surfactant is further added, and the monomer in which bubbles are finely dispersed by stirring at high speed, Stir and disperse at high speed in water containing a suspension stabilizer,
By forming oil droplets and applying temperature to initiate radical polymerization, fine particles having gas as a core are formed. Alternatively, commercially available hollow inorganic or organic fine particles as described below may be used. Hollow particles such as crosslinked polystyrene acrylic hollow particles SX866 and crosslinked polystyrene acrylic hollow particles GRANDOLL PP2000S manufactured by Dainippon Ink and Chemicals, Inc. manufactured by JSR Co., Ltd., such as SILAX-MS manufactured by Shirasu Co., Ltd. Ultrafine particle Shirasu balloons and hollow porous silica spherical particles such as Godball B-6C manufactured by Suzuki Yushi-Seiyaku Co., Ltd. can be used, and in some cases it is preferable to perform classification. Further, any hollow particles having a specific gravity of 1.2 or less and a particle diameter of 12 μm or less can be used without being limited to the above.

At least one kind or two or more kinds of the inorganic or organic fine particles may be used in the capsule particles.
Further, in the ink composition, two or more kinds of capsule particles of different kinds such as colorant and encapsulated particles of inorganic fine particles and capsule particles of encapsulated colorant and organic fine particles may be mixed. Further, in the coloring material, various known pigments and dyes can be used, and specifically, various carbon black, calcium carbonate, inorganic pigments such as titanium oxide and azo pigments, phthalocyanine pigments, anthraquinone pigments, Indigo-based pigments, melamine-based pigments, and other organic pigments and fluorescent pigments; among dyes, water-insoluble or sparingly soluble oil-soluble dyes are preferable, and specifically, solvent red, solvent blue, solvent orange, solvent green and oil Examples thereof include azo type dyes, phthalocyanine type dyes, anthraquinone type dyes and the like which are dyes usually used in ink compositions. You may use these pigments and dyes individually or in mixture of 2 or more types. A suspension stabilizer is used in suspension polymerization. Examples of the suspension stabilizer include water-soluble polymers such as gelatin, polyvinyl alcohol, methyl cellulose and carboxymethyl cellulose, or surfactants such as sodium dodecylbenzenesulfonate and sodium dodecyl sulfate, or tricalcium phosphate, calcium carbonate, and dioxide. It is preferable to use a solid fine powder such as titanium or nickel dioxide.

Since the inorganic or organic fine particles and the coloring material are encapsulated in the capsule particles by the above method, it is a necessary condition that they are well dispersed in the monomer phase. for that reason,
In order to easily disperse the inorganic or organic fine particles and the coloring material in the monomer phase, the surface of the inorganic or organic fine particles and the coloring material is subjected to a surface treatment with a silane coupling agent, a titanate coupling agent, a surfactant or the like. Good.
These coupling agents are appropriately selected according to the surface properties of the inorganic or organic fine particles and the coloring material. In particular,
In the silane coupling agent, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2
-Aminoethyl) aminopropylmethyldimethoxysilane, aminosilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane / hydrochloride, γ-glycidoxy Propyltrimethoxysilane, γ
-Mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilazane, γ-anilinopropyltrimethoxysilane, vinyltrimethoxysilane, etc. Examples of titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl tri-n-dodecylbenzenesulfonyl titanate,
Isopropyl tris (dioctyl pyrophosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (di-tridecyl)
Examples thereof include phosphite titanate, bis (dioctylpyrophosphate) oxyacetate titanate, bis (dioctylpyrophosphate) ethylene titanate, isopropyltri (dioctylphosphate) titanate, and isopropyltri (N-aminoethyl-aminoethyl) titanate. The inorganic or organic fine particles and the colorant-encapsulating capsule particles are preferably contained in the ink composition in an amount of 5% by weight to 35% by weight, 5% by weight
When the amount is less than 50%, the handwriting density is affected, and when it exceeds 35% by weight, the stability over time is affected.

The ink composition further contains a shear thinning agent, and the viscosity at 1.0 sec ^-1 is 800 to 3000.
0 mPa. s and the viscosity at 100 sec ^-1 is 2
0-2000 mPa. s (Haake Rheometer R
Those showing a value of 20 ° C. measured by S-75) are preferable. The shear thinning viscosity imparting agent is preferably one that is soluble or dispersible in water, and is not limited to the following and can be used. Examples of such shear thinning agents include xanthan gum, alka gum, gellan gum, guar gum, natural polysaccharides such as locust bean gum, hydroxymethyl cellulose, carboxymethyl cellulose, and other celluloses, polyacrylic acid, polyacrylic acid alkyl methacrylate copolymer. Acrylic acid polymers such as polymers and polyethylene glycol fatty acid esters can be used alone or in combination. Therefore, a preferred embodiment of the present invention is an eraser-erasable water-based ink composition for writing with a ballpoint pen, which comprises inorganic or organic fine particles, colorant-encapsulating capsule particles, water, a water-soluble organic solvent, and a shear thinning agent. 1 to 3 are enlarged cross-sectional views of a handwriting drawn with the ink composition of the present invention, schematically showing the state of capsule particles in the present invention. 1 and 2 show the case where inorganic or organic fine particles are mononuclearly encapsulated in the capsule particles, and the coloring material is localized near the outer surface of the fine particles. 1 shows the case where the inorganic or organic fine particles are hollow fine particles, and FIG. 2 shows the case where the inorganic or organic fine particles are non-hollow fine particles. FIG. 3 shows a case where mononuclear different kinds of inorganic or organic fine particles are included in the capsule particles,
This is the case where the coloring material is localized near the outer surface of the fine particles. 4 and 5 show a case where polynuclear inorganic or organic fine particles are encapsulated in capsule particles, FIG. 4 shows a case where the inorganic or organic fine particles are hollow fine particles, and FIG. 5 shows a case where the inorganic or organic fine particles are non-hollow. The case of fine particles is shown. Figure 1
In FIG. 5, 1 indicates hollow particles of inorganic or organic fine particles, 2 indicates coloring material, 3 indicates capsule particles, and 4 indicates non-hollow particles. In the present invention, mononuclear capsule particles and polynuclear capsule particles may be mixed in the ink composition, or capsule particles containing different fine particles may be mixed. Further, different fine particles such as hollow fine particles and non-hollow fine particles may be mixed in one capsule particle. The above-described eraser-erasable water-based ink composition is usually used as an ink for a writing instrument containing an ink composition. Specific examples thereof include a ballpoint pen, a marker, a felt-tip pen, etc., but are not limited thereto.

[0012]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited to the following examples. Example 1 Preparation of Organic Fine Particles and Capsule Particles Encapsulating Coloring Material 0.06 part of sodium dodecylbenzenesulfonate was dissolved in 400 parts of water, and further tricalcium phosphate 15
Parts were dispersed to form a continuous phase. 1.0 part of crosslinked acrylic monodisperse particles (trade name Chemisnow MX-150 manufactured by Soken Chemical Co., Ltd.) and 4.5 parts of carbon black (trade name SpecialBlack6 manufactured by Degussa Co., Ltd.) in the continuous phase.
32.4 parts of styrene, 11.39 parts of butyl acrylate,
A dispersion of 2.39 parts of 2,2′-azobisisobutyronitrile was added, and the mixture was stirred at high speed to form droplets having an average of about 4 μm,
Thereafter, the stirring power was weakened, and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, and an acid was added to the obtained slurry to remove tricalcium phosphate. Water was added to the obtained solid content by suction filtration to adjust the solid content to 50% by weight. The organic fine particles and the carbon black-containing capsule particles obtained at this time had an average particle diameter of about 4 μm.

Preparation of Eraser Erasable Water-based Ink Composition 32 parts of 50% by weight solids preparation of carbon black and crosslinked acrylic monodisperse particles (organic fine particles) -encapsulated capsule particles, water 40.56 parts, ethylene glycol 20
Part, triethylene glycol 5 parts, dispersant (trade name D
isperbyk190 manufactured by Big Chemie) 0.8
Parts, 0.3 parts of polyacrylic acid (trade name Carbopol 981 manufactured by BFGoodRich) as a viscosity adjusting agent, 1.0 part of pH adjusting agent triethanolamine, preservative (trade name Proxel GXL manufactured by I.C.I. ) 0.04 parts, rust preventive agent BTA (1,2,3-benzotriazole) 0.2
And TTA (4-methyl-1-H-benzotriazole) 0.1 part total 100 parts were stirred with a disper to obtain a black eraser erasable water-based ink composition. The viscosity of the ink composition is 11900 mPa.s at 1.0 sec ^-1 . s
And at 100 sec ⁻¹ , 749.8 mPa.s. It was s.

Example 2 Preparation of Organic Fine Particles 10 parts of polyvinyl alcohol (trade name Gohsenol GL-05 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was dissolved in 400 parts of water at 80 ° C. to form a continuous phase. 52 parts of styrene in the continuous phase,
A dispersion of 2.00 parts of 2,2′-azobisisobutyronitrile was added, and the mixture was stirred at high speed to form droplets having an average of about 3 μm,
Thereafter, the stirring power was weakened, and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, and the resulting slurry was thoroughly washed with water, suction filtered and dried. The organic fine particles thus obtained, that is, styrene monodisperse particles, had an average particle diameter of about 3 μm. Preparation of Organic Fine Particles and Capsule Particles Encapsulating Coloring Material 8 parts of polyvinyl alcohol (trade name: Gohsenol GL-05 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) in 80 parts of water
It was made to melt | dissolve at degree C and it was set as the continuous phase. 1.3 parts of the styrene monodisperse particles and a blue organic pigment (trade name He in the continuous phase)
liogenBlue L7101F BASF)
Add a dispersion of 5.0 parts, ethyl methacrylate 34.2 parts, butyl acrylate 12.82 parts, ethylene glycol dimethacrylate 2.0 parts, 2,2'-azobisisobutyronitrile 2.0 parts. , Stirring at high speed, average about 6 μm
, And then the stirring power was weakened, and suspension polymerization was carried out at 60 ° C. for 6 hours. After polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to prepare a solid content of 50% by weight. The organic fine particles and the blue organic pigment-containing capsule particles obtained at this time had an average particle diameter of about 6 μm. Preparation of Eraser Erasable Water-based Ink Composition 50% by Weight Solid Preparation of Blue Organic Pigment and Styrene Monodisperse Fine Particles (Organic Fine Particles) -Encapsulated Capsule Particles 40
Parts, water 27.5 parts, propylene glycol 25 parts, glycerin 5 parts, dispersant (trade name Azisper PW911 Ajinomoto Fine-Techno Co., Ltd.) 0.4 parts, viscosity modifier aca gum (trade name Akagam Hakuto Co., Ltd.) 0.3 parts, pH adjuster triethanolamine 1.0 part, preservative sodium benzoate 0.5 part, BTA 0.2 part, TTA 0.1 part 100 parts total 100 parts are stirred with a disper to erase the blue eraser. A water-based ink composition was obtained. The viscosity of the ink composition is 3469 mPa.s at 1.0 sec ^-1 . s and 10
77.87 mPa.s at ⁰ sec ^-1 . It was s.

Example 3 Preparation of Inorganic Fine Particles and Capsule Particles Encapsulating Coloring Material In 400 parts of water, hydroxypropylmethyl cellulose (trade name: Metroze 60SH, Shin-Etsu Chemical Co., Ltd.) 4.8
Parts were melted at 80 ° C. to obtain a continuous phase. Porous silica (trade name: Godball E-2C, manufactured by Suzuki Yushi Kogyo Co., Ltd.) and surface treatment of the continuous phase with a coupling agent, and red organic pigment (trade name: Chromophtal DPP Red BP Ciba Specialty Chemicals Co., Ltd.) ), 4 parts, methyl styrene 11.82 parts, butyl acrylate 38.45 parts,
2.00 parts of ethylene glycol dimethacrylate, 2,
A dispersion of 1.64 parts of 2′-azobisisobutyronitrile was added, and the mixture was stirred at a high speed to form droplets having an average of about 8 μm, after which the stirring power was weakened and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to adjust the solid content to 50% by weight. The inorganic fine particles and the red organic pigment-containing capsule particles obtained at this time had an average particle diameter of about 6 μm. Preparation of Eraser Erasable Water-based Ink Composition 50 parts by weight of solid content of the red organic pigment and the capsule particles encapsulating inorganic fine particles 50 parts, water 18.46 parts, ethylene glycol 10 parts, diethylene glycol 20 parts,
Dispersant (Product name Azisper PW911 Ajinomoto Fine Techno
Co., Ltd.) 0.6 part, viscosity modifier polyacrylic acid alkyl methacrylate copolymer (trade name PEMULEN TR-1
BFGoodRich) 0.2 parts, pH adjuster triethanolamine 0.4 parts, antiseptic (trade name Biosite 800)
S Taisho Technos Co., Ltd.) 0.04 part, rust preventive agent BTA 0.2 part, TTA 0.1 part total 100 parts were stirred with a disper to obtain a red eraser erasable water-based ink composition. When the viscosity of the ink composition is 1.0 sec ^-1 , it is 1
7750 mPa. s, and 69 at 100 sec ^-1
0 mPa. It was s.

Example 4 Preparation of Inorganic Fine Particles and Capsule Particles Encapsulating Coloring Material 400 parts of water was charged with methyl cellulose (trade name: Metroze SM
7 parts of Shin-Etsu Chemical Co., Ltd.) were melted at 70 ° C. to obtain a continuous phase. Porous silica whose surface is treated with a coupling agent on the continuous phase (trade name: Godball E-6C)
Suzuki Yushi Kogyo Co., Ltd.) and yellow organic pigment (trade name N)
OVOPERM YELLOW HR Hoechst)
6.0 parts, ethyl methacrylate 22.83 parts, butyl acrylate 25.63 parts, divinylbenzene 0.65 parts,
A dispersion of 2.00 parts of 2,2′-azobisisobutyronitrile was added, and the mixture was stirred at high speed to form droplets having an average of about 7 μm,
Thereafter, the stirring power was weakened, and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to adjust the solid content to 50% by weight. The inorganic fine particles and the yellow organic pigment-containing capsule particles obtained at this time had an average particle diameter of about 7 μm. Preparation of Eraser Erasable Water-based Ink Composition 42 parts by weight of solid content of the yellow organic pigment and inorganic fine particle-containing capsule particles, 25.5 parts, water 25.5 parts, ethylene glycol 10 parts, diethylene glycol 18 parts, dispersant styrene maleic acid Resin (Brand name Alaster 700
Arakawa Chemical Industry Co., Ltd.) 3 parts, viscosity modifier xanthan gum (trade name Echo Gum Dainippon Pharmaceutical Co., Ltd.) 0.
5 parts, antiseptic 0.5 part of sodium benzoate, 0.2 parts of pH adjuster sodium hydroxide aqueous solution 1N, rust preventive BT
A total of 100 parts of 0.2 parts of ATA and 0.1 parts of TTA was stirred with a disper to obtain a yellow eraser-erasable water-based ink composition.
The viscosity of the ink composition is 274 when the viscosity is 1.0 sec ^-1 .
8 mPa. s, and 74.36 at 100 sec ^-1
mPa. It was s.

Example 5 Preparation of Hollow Organic Fine Particles and Encapsulated Particles Containing Coloring Material 0.04 part of sodium dodecylbenzenesulfonate was dissolved in 400 parts of water, and further 7 parts of tricalcium phosphate was dispersed to form a continuous phase. 1.0 part of polystyrene acrylic hollow particles GRANDOLL PP2000S (manufactured by Dainippon Ink and Chemicals, Inc.) and blue organic pigment Helio were added to the continuous phase.
3. GenBlue L7101F (manufactured by BASF) 3 parts, ethyl methacrylate 34.24 parts, butyl acrylate 12.
82 parts, divinylbenzene 0.65 parts, 2,2'-azobisisobutyronitrile 1.64 parts dispersion were added, and the mixture was stirred at a high speed to form droplets having an average of about 8 μm, after which the stirring power was weakened. Suspension polymerization was carried out at 60 ° C. for 6 hours. After polymerization, water 5
After adding 00 ml and standing still for 6 hours, the supernatant was discarded and an acid was added to the obtained slurry to remove tricalcium phosphate. Water was added to the obtained solid content by suction filtration to adjust the solid content to 50% by weight. The hollow organic fine particles and the blue organic pigment-containing capsule particles obtained at this time had an average particle diameter of about 7 μm. Preparation of Eraser Erasable Aqueous Ink Composition 40 parts by weight of solid content of blue pigment and hollow polystyrene acrylic particle-encapsulated capsule particles 40 parts, water 41.05 parts, ethylene glycol 10 parts, diethylene glycol 7 parts, dispersant (commodity) First name Dispe
rbyk192 manufactured by BYK Chemie) 0.8 parts, as a viscosity adjusting agent, 0.3 parts of alka gum (trade name: Alka gum manufactured by Hakuto Co., Ltd.), pH adjusting agent diethanolamine 0.5.
Part, preservative (trade name: Caisson LX SF25, manufactured by Rohm and Haas Japan Co., Ltd.) 0.05 part, rust preventive agent BTA 0.2 part, TTA 0.1 part 100 parts total 100 parts by stirring with a disper blue An eraser-erasable water-based ink composition was obtained. The viscosity of the ink composition is 1650 mPa.s at 1.0 sec ^-1 . s, and 4 when 100 sec ^-1
5.93 mPa. It was s.

Example 6 Preparation of Hollow Inorganic Fine Particles and Encapsulated Particles Encapsulating Coloring Material 8 parts of polyvinyl alcohol (trade name Gohsenol GL-05 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was dissolved in 400 parts of water at 80 ° C. and continuously. Phased. The average particle size is 7 after classification into the continuous phase.
0.5 μm, surface-treated with a coupling agent, and 0.5 parts of Silux Fine Balloon SFB101 (manufactured by Shirasu Co., Ltd.) and Carbon Black Printe
x150T (manufactured by Degussa Corp.) 4 parts, styrene 31.2
5 parts, ethylhexyl acrylate 18.43 parts, 2,
A dispersion of 2.39 parts of 2′-azobisisobutyronitrile was added, and the mixture was stirred at a high speed to form droplets having an average of about 10 μm, after which the stirring power was weakened and suspension polymerization was carried out at 60 ° C. for 6 hours.
After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to adjust the solid content to 50% by weight. The hollow fine particles and the carbon black-encapsulating capsule particles obtained at this time had an average particle diameter of about 8 μm. Preparation of Eraser Erasable Water-based Ink Composition 42 parts by weight of carbon black and hollow inorganic fine particle-encapsulated capsule particles in solid content of 50 parts, water 30.75
Parts, propylene glycol 20 parts, triethylene glycol 5 parts, dispersant (trade name Disperbyk 180
0.2 parts by weight, manufactured by Big Chemie Co., Ltd., and xanthan gum (trade name by Echo Gum Dainippon Pharmaceutical Co., Ltd.), a viscosity modifier.
5 parts, pH adjusting agent sodium hydroxide 1N 1.2 parts, preservative (trade name Bioside 1700 Taisho Technos Co., Ltd.) 0.05 part, BTA 0.2 part, TTA 0.1 part 100 parts total with stirring. A black eraser erasable aqueous ink composition was obtained. The viscosity of the ink composition is 1.
When 0 sec ^-1 , it is 2447 mPa. s and 100s
When ec ^-1 , 76.45 mPa. It was s.

Example 7 Preparation of Organic Fine Particles and Capsule Particles Encapsulating Coloring Material 0.05 part of sodium dodecyl sulfate was dissolved in 400 parts of water and 16 parts of tricalcium phosphate was dispersed to obtain a continuous phase. Highly cross-linked styrene particles (trade name SX8704) in the continuous phase
JSR Co., Ltd.) and titanium dioxide (trade name: Diamond White TCR-37 Co., Ltd., Tochem Products Co., Ltd.) 7
Parts, ethylhexyl methacrylate 19.83 parts, butyl acrylate 38.45 parts, divinylbenzene 0.55
Part, 2,2′-azobisisobutyronitrile (1.00 part) was added, and the mixture was stirred at a high speed to form droplets of about 4 μm on average, and then the stirring power was weakened to carry out suspension polymerization at 60 ° C. for 6 hours. I did. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, and an acid was added to the obtained slurry to remove tricalcium phosphate. Water was added to the obtained solid content by suction filtration to adjust the solid content to 50% by weight. The organic fine particles and the titanium dioxide-containing capsule particles obtained at this time had an average particle diameter of about 4 μm. Preparation of Eraser Erasable Water-Based Ink Composition 60 parts by weight of titanium dioxide and highly crosslinked styrene particle-encapsulating capsule-encapsulated particles, 60 parts, water 12.5
Parts, propylene glycol 20 parts, triethylene glycol 5 parts, dispersant (trade name: Diperbyk 192
BIC Chemie) 1.2 parts, viscosity modifier xanthan gum (trade name Echo Gum Dainippon Pharmaceutical Co., Ltd.) 0.5
Part, antiseptic (trade name Hokuord A Kitako Chemical Industry Co., Ltd.
0.5 parts, rust preventive agent BTA 0.2 parts, TTA 0.1
A total of 100 parts was stirred with a disper to obtain a white eraser-erasable water-based ink composition. The viscosity of the ink composition is 2478 mPa.s at 1.0 sec ^-1 . s and 10
73.37 mPa.s at ⁰ sec ^-1 . It was s.

Comparative Example 1 Preparation of Coloring Material-Encapsulating Capsule Particles 0.06 part of sodium dodecylbenzenesulfonate was dissolved in 400 parts of water, and tricalcium phosphate 15 was added.
Partially dispersed to form a continuous phase. 4.5 parts of carbon black (trade name SpecialBlack6 manufactured by Degussa Co., Ltd.), 32.4 parts of styrene, and 1 part of butyl acrylate were added to the continuous phase.
Add a dispersion of 1.39 parts and 2,2'-azobisisobutyronitrile 2.39 parts, stir at high speed and average about 4μ.
Then, the stirring force was weakened and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, and an acid was added to the obtained slurry to remove tricalcium phosphate. Water was added to the obtained solid content by suction filtration to adjust the solid content to 50% by weight. The average particle size of the carbon black-encapsulated capsule particles obtained at this time was about 4 μm. Preparation of Ink Composition 32 parts of solid content 50% by weight of carbon black and encapsulated capsule particles, 40.56 parts of water, 20 parts of ethylene glycol, 5 parts of triethylene glycol, dispersant (trade name: Disperbyk 190, manufactured by BYK Chemie) 0.8 parts, 0.3 parts of polyacrylic acid (trade name Carbopol 981 BFGoodRich) as a viscosity modifier,
pH adjusting agent triethanolamine 1.0 part, antiseptic agent (trade name: Proxel GXL manufactured by UK IC) 0.0
4 parts, rust preventive agent BTA 0.2 parts, TTA 0.1 parts total 100
The part was stirred with a disper to obtain a black ink composition. When the viscosity of the ink composition is 1.0 sec ^-1 , it is 9622.
mPa. s, and 635.9 m when 100 sec ^-1
Pa. It was s.

Comparative Example 2 Preparation of Coloring Material-Encapsulating Capsule Particles 8 parts of polyvinyl alcohol (trade name: Gohsenol GL-05 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was added to 80 parts of water.
It was made to melt | dissolve at degree C and it was set as the continuous phase. Blue organic pigment (trade name Heliogen Blue L7101FB
5.0 parts, 34.2 parts ethyl methacrylate,
A dispersion of 12.82 parts of butyl acrylate, 2.0 parts of ethylene glycol dimethacrylate, and 2.0 parts of 2,2′-azobisisobutyronitrile was added, and the mixture was stirred at high speed to form droplets having an average of about 6 μm. , Then weaken the stirring power, 60 ℃ 6
Suspension polymerization was carried out for an hour. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to give a solid content of 5
It was adjusted to 0% by weight. The average particle diameter of the blue organic pigment-containing capsule particles obtained at this time was about 6 μm. Preparation of Ink Composition 40 parts by weight of solid content of the blue organic pigment-encapsulating capsule particles, 40 parts, water 27.5 parts, propylene glycol 25
Part, glycerin 5 parts, dispersant (trade name Azisper PW911
Ajinomoto Fine Techno Co., Ltd.) 0.4 parts, viscosity modifier Alkagum (trade name: Alkagum Hakuto Co., Ltd.) 0.3
Parts, pH adjuster triethanolamine 1.0 part, preservative sodium benzoate 0.5 part, BTA 0.2 part, TT
A 0.1 part total of 100 parts was stirred with a disper to obtain a blue ink composition. The viscosity of the ink composition is 1.0 se
When c ^-1 is 2607 mPa.s. s, 100 sec ^-1
Then 64.78 mPa. It was s.

Comparative Example 3 Preparation of Coloring Material-Encapsulating Capsule Particles Hydroxypropylmethylcellulose (trade name, Metroses 60SH, Shin-Etsu Chemical Co., Ltd.) 4.8 was added to 400 parts of water.
Parts were melted at 80 ° C. to obtain a continuous phase. 4 parts of a red organic pigment (trade name: Chromophtal DPP Red BP Ciba Specialty Chemicals Co., Ltd.) in the continuous phase, 11.82 parts of methyl styrene, 38.45 parts of butyl acrylate, 2.00 parts of ethylene glycol dimethacrylate, 2,2'-
A dispersion of 1.64 parts of azobisisobutyronitrile was added, and the mixture was stirred at a high speed to form droplets having an average of about 8 μm, after which the stirring power was weakened and suspension polymerization was carried out at 60 ° C. for 6 hours. After polymerization, add 500 ml of water, leave it for 6 hours, discard the supernatant,
Suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to adjust the solid content to 50% by weight. The average particle size of the red organic pigment-containing capsule particles obtained at this time was about 6
was μm. Preparation of Ink Composition 50 parts by weight of solid content of the red organic pigment-encapsulated capsule particles 50 parts, water 18.86 parts, ethylene glycol 10
Part, diethylene glycol 20 parts, dispersant (trade name Azisper PW911 Ajinomoto Fine Techno Co., Ltd.) 0.6
Parts, viscosity modifier: polyacrylic acid alkyl methacrylate copolymer (trade name: PEMULEN TR-1 BFGoodRich) 0.2 parts, preservative (trade name: Biosite 800S)
Taisho Technos Co., Ltd.) 0.04 parts, anti-rust agent BT
A red ink composition was obtained by stirring a total of 100 parts of A0.2 parts and TTA 0.1 parts with a disper. The viscosity of the ink composition is 15850 mPa.s at 1.0 sec ^-1 . s, and 525 mPa.s at 100 sec ^-1 . It was s.

Comparative Example 4 Preparation of Capsule Particles Encapsulating Coloring Material In 400 parts of water, methyl cellulose (trade name: Metroze SM
7 parts by Shin-Etsu Chemical Co., Ltd.) is melted at 70 ° C.,
A yellow organic pigment (trade name NOVOPERM in the continuous phase)
YELLOW HR Hoechst) 6.0 parts, ethyl methacrylate 22.83 parts, butyl acrylate 25.63
Part, divinylbenzene 0.65 part, and 2,2′-azobisisobutyronitrile 1.00 part dispersion were added, and the mixture was stirred at a high speed to form droplets of about 7 μm on average, and then the stirring force was weakened to 60 Suspension polymerization was carried out at 6 ° C for 6 hours. Water 50 after polymerization
After adding 0 ml and standing still for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to adjust the solid content to 50% by weight. The average particle size of the yellow organic pigment-containing capsule particles obtained at this time was about 7 μm. Preparation of Ink Composition 42 parts by weight of solid content 50% by weight of the yellow organic pigment-containing capsule particles, 25.5 parts of water, 10 parts of ethylene glycol,
18 parts of diethylene glycol, dispersant styrene maleic acid resin (trade name: Alastar 700 Arakawa Chemical Industry Co., Ltd.)
3 parts, viscosity adjusting agent xanthan gum (trade name: Echo Gum Dainippon Pharmaceutical Co., Ltd.) 0.5 parts, preservative sodium benzoate 0.5 parts, pH adjusting agent sodium hydroxide 1N aqueous solution 0.2 parts , Rust preventive agent BTA 0.2 parts, TTA
An ink composition was obtained by stirring a total of 0.1 parts of 100 parts with a disper. When the viscosity of the ink composition is 1.0 sec ⁻¹ , it is 2057 mPa.s. s, and 60.88 mPa.s at 100 sec ^-1 . It was s.

Comparative Example 5 Preparation of Encapsulated Particles Containing Coloring Material 0.04 part of sodium dodecylbenzenesulfonate was dissolved in 400 parts of water, and further 7 parts of tricalcium phosphate was dispersed to obtain a continuous phase. Blue organic pigment He is added to the continuous phase.
liogenBlue L7101F (manufactured by BASF) 3
Parts, ethyl methacrylate 34.24 parts, butyl acrylate 12.82 parts, divinylbenzene 0.65 parts, 2,
A dispersion of 1.64 parts of 2′-azobisisobutyronitrile was added, and the mixture was stirred at a high speed to form droplets having an average of about 8 μm, after which the stirring power was weakened and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, and an acid was added to the obtained slurry to remove tricalcium phosphate. Water was added to the obtained solid content by suction filtration to adjust the solid content to 50% by weight. The average particle size of the blue organic pigment-containing capsule particles obtained at this time was about 7
was μm. Preparation of Ink Composition 40 parts by weight of solid content of the blue pigment-encapsulating capsule particles 50 parts, water 41.05 parts, ethylene glycol 10 parts, diethylene glycol 7 parts, dispersant (trade name Dispe
rbyk192 manufactured by BYK Chemie) 0.8 parts, as a viscosity adjusting agent, 0.3 parts of Alka gum (trade name: Alka gum manufactured by Hakuto Co., Ltd.), pH adjusting agent diethanolamine 0.5.
Part, preservative (trade name: Caisson LX SF25, manufactured by Rohm and Haas Japan Co., Ltd.) 0.05 part, rust preventive agent BTA 0.2 part, TTA 0.1 part 100 parts total 100 parts by stirring with a disper blue An ink composition was obtained. The viscosity of the ink composition is 1436 mPa.s at 1.0 sec ^-1 .
s, and 41.98 mPa.s at 100 sec ^-1 . s
Met.

Comparative Example 6 8 parts of polyvinyl alcohol (trade name Gohsenol GL-05 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was dissolved in 400 parts of adjusted water of colorant-encapsulating capsule particles at 80 ° C. to form a continuous phase. Carbon black P in the continuous phase
rintex150T (manufactured by Degussa Co., Ltd.) 4 parts, styrene 31.25 parts, ethylhexyl acrylate 18.43
Part, 2,2'-azobisisobutyronitrile 2.39 parts of the dispersion is added, and the mixture is stirred at a high speed to form droplets of about 10 μm on average, after which the stirring power is weakened and suspension polymerization is carried out at 60 ° C. for 6 hours. I did. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, suction filtration was performed on the obtained slurry, and water was added to the obtained solid content to adjust the solid content to 50% by weight. The average particle size of the carbon black-encapsulated capsule particles obtained at this time was about 8 μm. Preparation of Ink Composition 42 parts by weight of solid content 50% by weight of the carbon black-encapsulated capsule particles, water 30.75 parts, propylene glycol 20 parts, triethylene glycol 5 parts, dispersant (trade name: Disperbyk 180 manufactured by Big Chemie)
0.2 part, viscosity adjusting agent xanthan gum (trade name: Echo Gum Dainippon Pharmaceutical Co., Ltd.) 0.5 part, pH adjusting agent sodium hydroxide 1N 1.2 parts, preservative (trade name Biocide 1700 Taisho Technos Co., Ltd.) ) 0.05 part, BT
A 0.2 part and TTA 0.1 part 100 parts total 100 parts were stirred with the disper and the black ink composition was obtained. The viscosity of the ink composition is 1964 mPa.s at 1.0 sec ^-1 . s, and 60.60 mPa.s at 100 sec ^-1 . It was s.

Comparative Example 7 Preparation of Capsule Particles Containing Coloring Material 0.05 part of sodium dodecyl sulfate was dissolved in 400 parts of water, and 16 parts of tricalcium phosphate was dispersed to obtain a continuous phase. In the continuous phase, 7 parts of titanium dioxide (trade name, Diawhite TCR-37 manufactured by Tochem Products Co., Ltd.), 19.83 parts of ethylhexyl methacrylate, 38.45 parts of butyl acrylate, 0.55 parts of divinylbenzene, 2 ，
A dispersion of 1.00 parts of 2′-azobisisobutyronitrile was added, and the mixture was stirred at a high speed to form droplets having an average of about 4 μm, after which the stirring power was weakened and suspension polymerization was carried out at 60 ° C. for 6 hours. After the polymerization, 500 ml of water was added and the mixture was allowed to stand for 6 hours, the supernatant was discarded, and an acid was added to the obtained slurry to remove tricalcium phosphate. Water was added to the obtained solid content by suction filtration to adjust the solid content to 50% by weight. The average particle diameter of the titanium dioxide-encapsulating capsule particles obtained at this time was about 4 μm. Preparation of ink composition Solid content of the titanium dioxide-encapsulating capsule particles is 50% by weight
Preparation 60 parts, water 12.3 parts, propylene glycol 2
0 parts, triethylene glycol 5 parts, dispersant (trade name
Diperbyk192 manufactured by Big Chemie) 1.2
Part, viscosity modifier xanthan gum (trade name: echo gum
0.5 part of pH adjuster sodium hydroxide 1.0N aqueous solution, preservative (trade name Hokude A Kitako Chemical Co., Ltd.) 0.5 part, Anticorrosion agent B
A total of 100 parts of TA 0.2 parts and TTA 0.1 parts was stirred with a disper to obtain a white ink composition. The viscosity of the ink composition is 2114 mPa.s at 1.0 sec ^-1 . s, and 66.45 mPa.s at 100 sec ^-1 . It was s. Density measurement and erasability test For density measurement, a high-quality paper was coated with a bar coater to a constant film thickness (33 μm), and the density was measured at 5 points with a 2112 type digital color densitometer (manufactured by Array Corp.) and averaged. The concentrations are shown in the table below. Model 2112 Digital Color Densitometer measures transmission and reflection densities of color and black and white images,
It is a densitometer that digitally displays over a density range of 0 to 4. 500 in the erasability test
4 reciprocal eraser under g load (Product name MONO PE-0
4A (Tonbo Pencil Co., Ltd.) was used for erasing, and the density after erasing was measured with a 2112 digital color densitometer. The hiding rate was measured for Example 7 and Comparative Example 7. For the hiding rate, use a hiding rate measuring paper (manufactured by Taiyu Equipment Co., Ltd.), coat the test paper with an applicator, and apply it to a spectrophotometer TC-1800MKII (Tokyo Denshoku Technical Center). Measure the Y value with the Y value of the black part of the test piece /
It was calculated by the Y value (%) of the white portion. Regarding the stability with time, the glass bottle was stored in a constant temperature bath at 50 ° C. for 5 months, and the degree of sedimentation was observed.

Example 8 Next, the properties of the ballpoint pen filled with the eraser-erasable water-based ink composition according to the present invention were examined. The ink composition shown in Example 1 and Comparative Example 1 was 0.7 mm.
A stainless steel ball-point pen tip that encloses a φ ball is filled into a polypropylene pipe with one end fitted, and this is written with a PS-5 type disk drawing machine (manufactured by Seiki Kogyo Kenkyusho) at a writing speed of 51.67 mm. / sec load 200g Continuous writing at a writing angle of 70 °, and this handwriting is 500g load 4 reciprocations using an eraser tester, eraser (product name M
Erase with ONOPE-04A (manufactured by Tombow Pencil Co., Ltd.), and set 100-{(density after erasing / density before erasing) × 100} = erasure rate (%), and erase rate (%) I put it out. Also, in the state of the pen of the ballpoint pen,
It was stored for a month and the writing state was confirmed.

[0028]

[Table 1]

[0029]

[Table 2]

[0030]

[Table 3]

[0031]

[Table 4]

[0032]

[Table 5]

[0033]

[Table 6]

[0034]

[Table 7]

[0035]

[Table 8]

[0036]

INDUSTRIAL APPLICABILITY According to the present invention, by encapsulating inorganic or organic fine particles in capsule particles, the ballpoint pen ink composition can be left deep and clear on the paper surface, and even in the handwriting, the effect of the included fine particles makes it more preferable to use an eraser. It is possible to provide an eraser-erasable water-based ink composition which can be easily erased and is excellent in stability over time by adjusting the specific gravity of the encapsulated fine particles and the specific gravity of the ink medium, and a ballpoint pen using the same.

[Brief description of drawings]

FIG. 1 is an enlarged cross-sectional view of handwriting drawn with the ink composition of the present invention, where the inorganic or organic fine particles are hollow fine particles.

FIG. 2 is an enlarged cross-sectional view of handwriting drawn with the ink composition of the present invention, where the inorganic or organic fine particles are non-hollow fine particles.

FIG. 3 is an enlarged cross-sectional view of handwriting drawn with the ink composition of the present invention, in which capsule particles containing different kinds of inorganic or organic particles are mixed.

FIG. 4 is an enlarged cross-sectional view of a handwriting drawn with the ink composition of the present invention. 1 When a plurality of hollow inorganic or organic fine particles are present in the capsule particles,

FIG. 5 is an enlarged cross-sectional view of a handwriting drawn with the ink composition of the present invention 1. When a plurality of non-hollow inorganic or organic fine particles are present in the capsule particles

[Explanation of symbols]

1 Inorganic or organic hollow particles 2 Colorant
3 Capsule particles 4 Inorganic or organic non-hollow particles

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] November 27, 2001 (2001.11.
27)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0027

[Correction method] Change

[Correction content]

Next, the characteristics of the ballpoint pen filled with the eraser-erasable water-based ink composition according to the present invention were examined. The ink composition shown in Example 1 and Comparative Example 1 was filled into a polypropylene pipe having a stainless steel ball-point pen tip enclosing a 0.7 mmφ ball fitted at one end, and this was filled with a PS-5 type disc-shaped drawing line. Writing speed 51.67 mm / sec load 2 with a machine (made by Seiki Kogyo Kenkyusho)
It was continuously written at a writing angle of 00g of 00g, and the handwriting was erased with an eraser (trade name: MONOPE-04A (manufactured by Tonbo Pencil Co., Ltd.)) under a 500g load for 4 reciprocations using a erasing tester. {(Density after erasing / density before erasing) x 100} = erasure rate (%), and the erasure rate (%) was calculated.
It was stored in a constant temperature bath for 5 months and the state of writing was checked.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazuaki Sato             6-10-12 Toshima, Kita-ku, Tokyo Co., Ltd.             Inside the dragonfly pencil F-term (reference) 2C350 GA03 GA04 NA19                 4J039 AD03 AD09 AD10 AD11 AD12                       AD14 AD15 AD22 BA04 BA13                       BA16 BC30 BC39 BC40 BC56                       BC57 BC60 BD03 BE01 BE02                       BE06 BE12 BE23 CA03 CA06                       CA11 GA27

Claims (8)

[Claims] 1. Capsule particles, a water-soluble organic solvent, and
An eraser-erasable water-based ink composition comprising water, wherein at least a part of the surface of the capsule particles is made of a polymer having an adhesive property as a wall material, and inside thereof, a coloring material as a core material and a particle size distribution of 0 are provided. Including inorganic or organic fine particles of 1 μm to 12 μm, the coloring material is localized near the outer surface of the inorganic or organic fine particles, and the particle size distribution of the capsule particles is 1 μm to 20 μm. An eraser-erasable water-based ink composition characterized by: 2. The eraser-erasable water-based ink composition according to claim 1, wherein the polymer, which is a wall material of the capsule particles, has a glass transition temperature of 60 ° C. or lower. 3. The eraser-erasable water-based ink composition according to claim 1, wherein the capsule particles are prepared by a suspension polymerization method. 4. The eraser-erasable water-based ink composition according to claim 1, wherein the inorganic or organic fine particles in the capsule particles have a specific gravity of 1.2 or less and are hollow or non-hollow substances. 5. The ink composition comprises 5 capsule particles.
The eraser-erasable water-based ink composition according to claim 1, which is contained in an amount of 35% by weight to 35% by weight. 6. A shear thinning agent is added to the ink composition.
Including, 1.0sec ^-1Viscosity at 800 ~ 30000m
Pa. s and 100 sec^-1Viscosity at 20 ~
2000 mPa. s (Haake Rheometer RS-
The value of 20 ° C. measured at 75).
Eraser Erasable water-based ink composition. 7. A writing instrument using the eraser-erasable water-based ink composition according to any one of claims 1 to 6. 8. A water-insoluble monomer in which an oil-soluble polymerization initiator, inorganic or organic fine particles and a coloring material are dispersed or dissolved is dispersed in water containing a dispersant as oil droplets to polymerize the dispersion system, A process for producing an eraser-erasable water-based ink composition, which comprises producing polymer capsule particles containing inorganic or organic fine particles and a coloring material as a core substance.