JP2008001832A - Aqueous ink composition for writing implement and writing implement building it in - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous ink for a writing implement capable of improving the waterproof property of pigment ink, also exhibiting a sufficient handwriting-fixing property even on writing on an ink-unpenetrable surface such as that of a resin film, and a writing implement building it in. <P>SOLUTION: This aqueous ink composition for the writing implement contains at least a pigment, water, and polycarbonate polyol copolymerization type urethane emulsion. The emulsion is added into the total ink composition by 1 to 15 wt.% range as a resin solid portion. The writing implement building-in the aqueous ink composition for the writing implement is also provided. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water-based ink composition for a writing instrument and a writing instrument incorporating the same. Furthermore, the present invention relates to a water-based ink composition for a writing instrument having excellent fixability when written on a non-penetrating surface and a writing instrument incorporating the same.

Conventionally, water-based inks using pigments as colorants have been widely used because of their excellent light resistance and water resistance of handwriting compared to dyes, and further, resins are blended as additives in the inks. (For example, refer to Patent Documents 1 and 2).
In the ink described in Patent Document 1, an acrylic acid resin or a maleic acid resin is added, and a pigment dispersion effect or a water resistance improvement effect can be obtained by the resin, but when writing on a non-penetrating surface such as a resin film The handwriting fixability required for the ink was not sufficient, and the handwriting was easily peeled off by rubbing.
In addition, the ink described in Patent Document 2 improves the water resistance of handwriting by adding an acrylic resin emulsion and imparts handwriting fixability to a non-penetrating surface. However, although the water resistance of the handwriting can be improved, a sufficient effect cannot be obtained in the handwriting fixing ability, and the handwriting easily peels off depending on the rubbing conditions.
JP 58-80368 A JP 11-193362 A

  The present invention is capable of improving the water resistance of pigment inks, and also provides a water-based ink composition for a writing instrument that can exhibit sufficient handwriting fixability even when written on an ink non-penetrating surface such as a resin film. Is to provide a writing instrument.

The water-based ink composition for a writing instrument of the present invention is required to contain at least a pigment, water, and a polycarbonate polyol copolymer urethane emulsion.
Furthermore, it is required that the emulsion is added in the range of 1 to 15% by weight of resin solid content in the total amount of the ink composition, and that a fluorine-based surfactant or a silicone-based surfactant is added.
Furthermore, the writing instrument is provided with a built-in water-based ink composition for writing instruments, and the writing instrument comprises a fiber processed body in which a large number of fibers are arranged in close contact with each other and a capillary gap is formed between adjacent fibers. It is a requirement that the marking pen has a nib.

  The water-based ink composition for a writing instrument of the present invention can improve the water resistance of pigment ink by blending a polycarbonate polyol copolymer type urethane emulsion, and has sufficient handwriting on an ink non-penetrating surface such as a resin film. Fixability can be expressed.

  The polycarbonate polyol copolymer urethane emulsion is an emulsion of a urethane resin in which various compounds having an isocyanate group and the hydroxyl group of the polycarbonate polyol are copolymerized, and exhibits excellent fixing power when added to water-based ink. . In particular, the fixability is high even on an ink non-penetrating surface such as a resin film, and handwriting peeling due to rubbing or the like hardly occurs.

The polycarbonate polyol copolymer urethane emulsion can be added in an amount of 1 to 15% by weight, preferably 2 to 10% by weight, based on the resin solid content in the ink composition.
If it is less than 1% by weight, it is difficult to obtain the desired fixing property, and even if it exceeds 15% by weight, no further improvement in fixing property can be obtained, so no further addition is required.

As the pigment, any pigment that can be dispersed in an aqueous medium can be used. In addition to inorganic pigments such as carbon black and ultramarine, and organic pigments such as copper phthalocyanine blue and benzidine yellow, a surfactant or a resin is used in advance. For example, water-dispersed pigment products that are finely and stably dispersed in an aqueous medium are used. I. Pigment Blue 15: 3B [Product name: Sandy Super Blue GLL, pigment content 24%, manufactured by Sanyo Dye Co., Ltd.]
C. I. Pigment Red 146 [Product name: Sandye Super Pink FBL, pigment content 21.5%, manufactured by Sanyo Dye Co., Ltd.]
C. I. Pigment Yellow 81 [Product name: TC Yellow FG, pigment content about 30%, manufactured by Dainichi Seika Kogyo Co., Ltd.]
C. I. Pigment Red 220/166 [Product name: TC Red FG, pigment content of about 35%, manufactured by Dainichi Seika Kogyo Co., Ltd.].
As the resin for dispersing the pigment, polyamide resin, polyurethane resin, polyester resin, epoxy resin, melamine resin, phenol resin, silicone resin, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl acetate, polyvinyl chloride, polyvinylidene chloride, Examples thereof include polystyrene, acrylic acid resin, maleic acid resin, gum arabic, cellulose, dextran, casein, and derivatives thereof, and copolymers of the above-described resins.
As the fluorescent pigment, a fluorescent pigment in the form of fine particles of a synthetic resin in which various fluorescent dyes are formed into a solid solution in a resin matrix can be used.
In addition, white pigments such as titanium dioxide, metal powders such as aluminum, natural mica, synthetic mica, alumina, pearl pigments in which the surface of the core material is coated with a metal oxide such as titanium dioxide, cholesteric liquid crystal type glitter A functional pigment or the like can also be used.
Furthermore, a microcapsule pigment encapsulating a reversible thermochromic composition, or a thermochromic pigment such as a microcapsule pigment encapsulating a dye or pigment together with the reversible thermochromic composition can also be used.
The pigments can be used alone or in combination of two or more, and are used in the range of 1 to 25% by weight, preferably 2 to 15% by weight in the ink composition.

Furthermore, it is also possible to use a dye that can be dissolved or dispersed in an aqueous medium in combination with the pigment.
As the dye, an acid dye, a basic dye, a direct dye, or the like can be used. Examples of the acid dye include neucoccine (CI. 16255), tartrazine (CI. 19140), and acid blue. Black 10B (C.I. 20470), Guinea Green (C.I. 42085), Brilliant Blue FCF (C.I. 42090), Acid Violet 6B (C.I. 42640), Soluble Blue (C.I. 42755), naphthalene green (C.I.44025), eosin (C.I.45380), phloxine (C.I.45410), erythrosine (C.I.45430), nigrosine (C.I.50420), acid Flavin (C.I. 56205) or the like is used.

  Examples of basic dyes include chrysoidine (C.I. 11270), methyl violet FN (C.I. 42535), crystal violet (C.I. 42555), malachite green (C.I. 42000), Victoria blue FB ( CI 44045), rhodamine B (C.I. 45170), acridine orange NS (C.I. 46005), methylene blue B (C.I. 52015) and the like are used.

  As direct dyes, Congo Red (C.I. 22120), Direct Sky Blue 5B (C.I. 24400), Violet BB (C.I. 27905), Direct Deep Black EX (C.I. 30235), Kaya Las Black G Conch (C.I. 35225), Direct Fast Black G (C.I. 35255), Phthalocyanine Blue (C.I. 74180) and the like are used.

A water-soluble organic solvent can be added to the ink. As the water-soluble organic solvent, a conventional general-purpose solvent compatible with water is used. Ethanol, propanol, butanol, glycerin, sorbitol, ethylene glycol, diethylene glycol, thiodiethylene glycol, hexylene glycol, 1,3-butanediol, Neoprene glycol, polyethylene glycol, propylene glycol, butylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, 2 -Pyrrolidone, N-methyl-2-pyrrolidone, etc. It is.
In addition, the said water-soluble organic solvent can also use 1 type (s) or 2 or more types together, and is used in 2-60 weight% in an ink composition, Preferably it is 5-35 weight%.

In addition, a pH adjuster, an antiseptic, or an antifungal agent can be added as necessary.
Examples of the pH adjuster include volatile amine compounds such as ammonia, lactic acid, and citric acid.
Examples of the preservative or antifungal agent include carboxylic acid, sodium salt of 1,2-benzisothiazolin-3-one, sodium benzoate, sodium dehydroacetate, potassium sorbate, propyl paraoxybenzoate, 2,3,5,6 -Tetrachloro-4- (methylsulfonyl) pyridine and the like.
Furthermore, anti-foaming agents and antioxidants such as fluorine surfactants, silicone surfactants, nonions, anions, cationic surfactants, and dimethylpolysiloxane that improve the permeability of the solvent can also be added. .
In particular, among the surfactants, fluorine surfactants and silicone surfactants are preferably used because they have a high effect of suppressing ink repellency when written on an ink non-penetrating surface such as a resin film. Further, by adding the surfactant, a uniform coating film can be formed when writing on the ink non-penetrating surface, so that the handwriting is more difficult to peel off.

  In addition, one or more water-soluble resins such as alkyd resin, acrylic resin, styrene maleic acid copolymer, cellulose derivative, polyvinyl pyrrolidone, polyvinyl alcohol and dextrin are added in combination with polycarbonate polyol copolymer urethane emulsion. In addition, one or more wetting agents such as urea, nonionic surfactant, sorbit, mannitol, sucrose, glucose, reduced starch hydrolyzate, sodium pyrophosphate and the like can be added.

A shear thinning agent can be added to the water-based ink composition.
As the shear thinning agent, a water-soluble or dispersible substance is effective, and xanthan gum, welan gum, and succinoglycan whose constituent monosaccharide is an organic acid-modified heteropolysaccharide of glucose and galactose (average molecular weight) About 1,000 to 8 million), guar gum, locust bean gum and derivatives thereof, hydroxyethyl cellulose, alginic acid alkyl esters, polymers having a molecular weight of 100,000 to 150,000 based on alkyl esters of methacrylic acid, glucomannan, agar and carrageenan Thickening polysaccharides having gelling ability extracted from seaweed such as benzylidene sorbitol and benzylidene xylitol or derivatives thereof, crosslinkable acrylic acid polymer, inorganic fine particles, polyglycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, poly Tylene glycol fatty acid ester, polyoxyethylene castor oil, polyoxyethylene lanolin, lanolin alcohol, beeswax derivative, polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyoxyethylene alkyl phenyl ether, fatty acid amide, etc. have an HLB value of 8 to Twelve nonionic surfactants, salts of dialkyl or dialkenylsulfosuccinic acid and the like can be exemplified, and they can be used alone or in combination.
Furthermore, a mixture of N-alkyl-2-pyrrolidone and an anionic surfactant, a mixture of polyvinyl alcohol and an acrylic resin can also be used.
The shear thinning agent can be used in the range of 0.1 to 20% by weight in the ink composition.

In addition, a rust preventive agent, a lubricant, etc. can be added as needed.
Examples of the rust inhibitor include benzotriazole and derivatives thereof, tolyltriazole, dicyclohexylammonium nitrite, diisopropylammonium nitrite, sodium thiosulfate, ethylenediaminetetraacetate, saponin, and dialkylthiourea.
Examples of the lubricant include phosphate ester surfactants, metal soaps, polyalkylene glycol fatty acid esters, ethylene oxide addition type cationic surfactants, phosphate ester activators, thiocarbamates, and dimethyldithiocarbamates. It is done.

The ink composition is put into practical use by filling a general-purpose writing instrument such as a marking pen, a ballpoint pen, and a fountain pen with various pen tips attached to the writing tip.
Among the nibs, as the marking pen tip, for example, a fiber tip, a felt tip, a plastic tip, a brush, etc. can be applied, and as a ball-point pen tip, the vicinity of the tip of a metal pipe is pressed and deformed inward from the outer surface. A chip formed by holding a ball in the ball holding part, a chip formed by holding a ball in a ball holding part formed by cutting a metal material by a drill or the like, and a resin made inside a metal or plastic chip A chip provided with a ball seat or a ball held by the chip and biased forward by a spring body can be applied. The ball may be made of cemented carbide, stainless steel, ruby, ceramic, resin, rubber, or the like, and those having a diameter in the range of 0.1 mm to 3.0 mm are preferably used.
Further, as the pen tip in the form of a fountain pen, a metal plate such as a stainless steel plate or a gold alloy plate cut into a taper taper shape, bent or curved, or resin molded into a pen tip shape can be applied. The pen body can be provided with a slit at the center or a ball at the tip.

When filling the marking pen, the structure and shape of the marking pen itself are not particularly limited. For example, the ink is impregnated with an ink occlusion body made of a fiber bundle housed in the shaft tube, and the ink is applied to the writing tip. Supply structure, ink is stored directly inside the shaft cylinder, ink flow rate adjusting member made of comb groove or ink flow rate adjusting member consisting of fiber bundle is interposed, ink is stored directly inside the shaft cylinder, and the valve mechanism A marking pen having a structure for supplying a predetermined amount of ink to the writing tip portion may be mentioned.
When filling the ball-point pen, the structure and shape of the ball-point pen itself are not particularly limited. For example, an ink occlusion body composed of a fiber bundle housed in the shaft tube is impregnated with ink and supplied to the writing tip. Structure, structure in which ink is stored directly in the shaft cylinder, and an ink flow rate adjusting member consisting of a comb groove-like ink flow rate adjusting member or fiber bundle is interposed, a chip with a ball attached to the tip is directly or via a connecting member Examples include a structure in which a liquid stopper for preventing ink and backflow is accommodated in a connected shaft cylinder, and a structure in which a ball pen refill in which a liquid stopper for preventing ink and backflow is accommodated in an ink accommodating tube is accommodated in the axis cylinder.

For example, a molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, or nylon is used as the shaft cylinder or the ink storage tube for storing ink.
The molded body may have transparency, and transparency includes colored transparency, translucency, and colored translucency, and can confirm the ink color, the remaining amount of ink, and the like.
In addition, the transparent shaft cylinder or the ink storage tube may have transparency as a whole, or may have a partially transparent portion where the remaining amount of ink can be visually recognized.

The back end of the ink stored in the ink storage tube or the shaft tube may be filled with an ink backflow prevention body.
The ink backflow prevention body composition is composed of a non-volatile liquid or a hardly volatile liquid.
Specifically, petroleum jelly, spindle oil, castor oil, olive oil, refined mineral oil, liquid paraffin, polybutene, α-olefin, α-olefin oligomer or co-oligomer, dimethyl silicone oil, methylphenyl silicone oil, amino-modified silicone oil, Examples thereof include polyether-modified silicone oil and fatty acid-modified silicone oil, and one or more can be used in combination.

The non-volatile liquid and / or the hardly volatile liquid is preferably added with a gelling agent to increase the viscosity to a suitable viscosity. , Swellable mica, hydrophobic thickeners such as bentonite and montmorillonite, fatty acid metal soaps such as magnesium stearate, calcium stearate, aluminum stearate, zinc stearate, tribenzylidene sorbitol, fatty acid amide, amide modified Examples include dextrin compounds such as polyethylene wax, hydrogenated castor oil, fatty acid dextrin, and cellulose compounds.
Furthermore, the liquid ink backflow prevention body composition and a solid ink backflow prevention body composition can be used in combination.

The writing instrument form of the present invention is not limited to the one described above, and may be a double-headed writing instrument in which pen bodies having different forms are mounted or pen bodies that lead out inks having different colors are mounted.
As the double-headed writing instrument, a partition wall is provided in the shaft cylinder, and the writing tip is fixed to the both ends of the shaft cylinder directly or via a relay member, respectively. In a writing instrument or a shaft tube, two refills are stored so that the writing tip is located at both ends of the shaft tube, and each of the two refills has a different color tone. The writing instrument which accommodates can be illustrated.

  In particular, the writing feeling is good when writing on the ink non-penetrating surface, the ink followability is stable, and the writing surface is hard to be damaged. It is most suitable to use in the form of a marking pen having a pen tip made of a fiber processed body in which a capillary gap is formed.

The ink compositions of Examples and Comparative Examples are shown in the following table.
In addition, the numerical value of a composition in a table | surface shows a weight part.

The contents of the raw materials in the table are explained according to the note numbers.
(1) 30% carbon black nonionic activator dispersion, manufactured by Sanyo Dye Co., Ltd., trade name: SANDY SUPER BLACK C
(2) Dispersion obtained by dispersing carbon black (25%) in 5% acrylic resin aqueous solution (3) Polycarbonate urethane resin emulsion, manufactured by Avicia, trade name: NEOREZ R-9603, solid content 34%
(4) Polycarbonate urethane resin emulsion, manufactured by Nippon Polyurethane Co., Ltd., trade name: WPC-101, solid content 40%
(5) Acrylic-styrene resin emulsion, manufactured by Johnson Polymer Co., Ltd., trade name: Jonkrill 74J, solid content 45%
(6) Polyester-urethane resin emulsion, manufactured by Avicia, trade name: NEOREZR-960, solid content 33%
(7) Fluorosurfactant, manufactured by Dainippon Ink & Chemicals, Inc., trade name: Megafac F120
(8) Silicone surfactant, manufactured by Toray Dow Corning Co., Ltd., trade name: FZ2163

Preparation of Ink Compositions other than the processed pigment among the compositions of the above Examples and Comparative Examples were mixed and stirred uniformly, and then the mixed solution was added to the processed pigment in a stirred state, and 20 ° C with a disper. Was stirred for 1 hour to obtain a water-based ink composition for writing instruments.

Preparation of marking pen An aqueous marking pen was obtained by filling 1.5 g of the obtained ink composition into a commercially available marking pen (Pilot Corporation; SGR-8SL).

Scratch resistance test Using each marking pen, write 5 consecutive circles on a transparent PET film in an environment of 20 ° C. and 60% humidity, and let stand for 24 hours.
The handwriting state at the time of moving and rubbing on the handwriting with a tissue paper carrying 200 g of weight was visually observed.

Water resistance test Using each marking pen, write 5 circles continuously on a transparent PET film in an environment of 20 ° C and 60% humidity. After leaving for 24 hours, the PET is soaked in water. The state of the handwriting after immersing the film in water for 1 hour was visually observed.
The test results are shown in the following table.

The contents of the symbols in the table will be described below.
Scratch resistance test A: No change in handwriting.
○: Slight peeling is observed in the handwriting, but there is no practical problem.
(Triangle | delta): Handwriting peeling is seen partially.
X: Most of the handwriting is peeled off.
Water resistance test ○: No change from before immersion.
X: The handwriting is peeled off and cannot be visually recognized.

Claims (5)

  A water-based ink composition for a writing instrument, comprising at least a pigment, water, and a polycarbonate polyol copolymer urethane emulsion.   The water-based ink composition for a writing instrument according to claim 1, wherein the emulsion is added to the total amount of the ink composition in a range of 1 to 15% by weight in terms of resin solids.   3. A water-based ink composition for a writing instrument according to claim 1 or 2, wherein a fluorine-based surfactant or a silicone-based surfactant is added.   A writing instrument incorporating the water-based ink composition for a writing instrument according to any one of claims 1 to 3.   5. The marking pen according to claim 4, wherein the writing instrument is a marking pen having a nib made of a fiber processed body in which a large number of fibers are arranged in close contact with each other and a capillary gap is formed between adjacent fibers. Writing instrument.