JP4838914B2 - Water-based ink composition for writing instruments and writing instrument using the same - Google Patents

Description

  The present invention relates to a water-based ink composition for writing instruments. More specifically, the present invention relates to a water-based ink composition for writing instruments having improved ink outflow properties.

Writing tools such as fountain pens, ballpoint pens, marking pens, etc., supply ink in the ink tanks such as shafts, refills, cartridges, etc. to the pen tip provided at the tip of the writing and draw the ink from the pen tip by writing to write the writing surface Form handwriting.
For the ink tank, general-purpose plastic materials such as polyethylene, polypropylene, polystyrene, acrylonitrile-butadiene-styrene copolymer (ABS), polyvinyl chloride, and polyester are used, all of which are hydrophobic.
In addition, water-based ink for writing instruments has a poor ink wettability with respect to the ink guiding member from the ink tank to the pen tip and the pen tip, and the ink spillage tends to be impaired. Although the recovered state is restored by writing, there may be a repetitive phenomenon of thinning after that, or writing may become impossible.
In addition, in order to solve the above-mentioned problems, the wettability of the ink is improved, the lubricity of the ball and the ball seat is improved in the water-based ballpoint pen, and the pigment is dispersed in the ink in which the pigment is used as the colorant. Attempts have been made to add surfactants such as polyoxyethylene alkylphenyl ether and sodium lauryl sulfate for the purpose of the agent, but the effect is not sufficient, and if a large amount of the surfactant is added, paper fibers There was a tendency to cause penetrating of ink by penetrating into the space, or to cause excess ink outflow (ink drips) from the pen tip due to a decrease in ink surface tension (see, for example, Patent Documents 1 and 2). .
JP-A-10-298482 Special Table 2000-515925

  The present invention uses a water-based ink composition for a writing instrument and a writing instrument that can improve writing feeling by imparting lubrication performance when used in a ballpoint pen, in which handwriting always shows a constant concentration, hardly causes bleeding. I want to provide a writing instrument.

The present invention requires a water-based ink composition for a writing instrument comprising at least a colorant, water, and polyglycerin-modified silicone.
Furthermore, it is required that the polyglycerin-modified silicone is contained in an ink composition in an amount of 0.01 to 2 parts by weight and a shear thinning agent is included.
Furthermore, a writing instrument in the form of a ballpoint pen containing the water-based ink composition for a writing instrument is required.

  The present invention contains a polyglycerin-modified silicone in the ink composition, so that the ink guide member that communicates between the ink tank and the writing tip, or the inner wall of the pen tip provided at the writing tip is well wetted. Since it sometimes causes smooth ink outflow from the ink tank to the nib, it is possible to provide a water-based ink composition for a writing instrument that can form a good handwriting without blur and a writing instrument using the same.

  As the polyglycerin-modified silicone used in the present invention, a compound represented by the following formula (1) is preferably used.

（式中、ｍ，ｎはそれぞれ１以上の整数を示し、Ｒ₁ はアルキル基、アルケニル基、シクロアルキル基、アリール基、これらの基の水素原子が部分的にハロゲン原子で置換された基、ポリオキシアルキレン基を示し、そのうち少なくとも１つ以上は下記式（２）〜（８）から選ばれるポリグリセリン基である。）

（式中、Ｑは炭素数１〜１０のアルキレン基を示し、Ｒ₂ は水素又は炭素数１〜３０のアルキル基を示し、ｐ、ｑ、ｒ、ｓ、ｔ、ｕ、ｖはそれぞれ１以上の整数を示す。）

(In the formula, m and n each represent an integer of 1 or more, R ₁ represents an alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, a group in which the hydrogen atoms of these groups are partially substituted with halogen atoms, A polyoxyalkylene group, of which at least one is a polyglycerin group selected from the following formulas (2) to (8).

(In the formula, Q represents an alkylene group having 1 to 10 carbon atoms, R ₂ represents hydrogen or an alkyl group having 1 to 30 carbon atoms, and p, q, r, s, t, u, v are each 1 or more. Indicates an integer.)

The polyglycerin-modified silicone is added to the ink composition in an amount of 0.01 to 2 parts by weight, preferably 0.1 to 2 parts by weight, more preferably 0.1 to 1 part by weight.
If the amount is less than 0.01 parts by weight, it is difficult to obtain a desired effect, and a sufficient effect is obtained with an addition amount of 2 parts by weight or less, so that no further addition is required.
The polyglycerin-modified silicone can improve the ink outflow property, and when stored in a ballpoint pen for practical use, the ball holding portion of the ballpoint pen tip used in the ballpoint pen is worn by the rotation of the ball. Can also be reduced.

As the colorant, all dyes and pigments that can be dissolved or dispersed in an aqueous medium can be used, and specific examples thereof are exemplified below.
As an acid dye,
New coccin (CI. 16255),
Tartrazine (C.I. 19140),
Acid Blue Black 10B (C.I. 20470),
Guinea Green (C.I.42085),
Brilliant blue FCF (C.I.42090),
Acid Violet 6BN (C.I. 43525),
Soluble Blue (C.I. 42755),
Naphthalene green (C.I. 44025),
Eosin (C.I. 45380),
Phloxin (C.I. 45410),
Erythrosine (C.I. 45430),
Nigrosine (C.I. 50420),
Acid flavin (C.I. 56205) or the like is used.

As basic dye,
Chrysoidine (C.I. 11270),
Methyl violet FN (C.I. 42535),
Crystal violet (C.I. 42555),
Malachite green (C.I. 42000),
Victoria Blue FB (C.I. 44045),
Rhodamine B (C.I. 45170),
Acridine orange NS (C.I. 46005),
Methylene blue B (C.I. 52015) or the like is used.

As a direct dye,
Congo Red (C.I. 22120),
Direct Sky Blue 5B (C.I. 24400),
Violet BB (C.I. 27905),
Direct deep black EX (CI 30235),
Caillas Black G Conch (C.I. 35225),
Direct Fast Black G (C.I. 35255),
Phthalocyanine blue (C.I. 74180) or the like is used.
When a dye is used as the colorant, dry-up is significant in a system applied to a knock-type ballpoint pen that does not require a cap, and the dry-up resistance is an important requirement.

Examples of the pigment include inorganic pigments such as carbon black and ultramarine, and organic pigments such as copper phthalocyanine blue and benzidine yellow, as well as water dispersion finely and stably dispersed in an aqueous medium in advance using a surfactant or resin. Pigment products and the like 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 a water-dispersed pigment using a water-soluble resin,
C. I. Pigment Black 7 (trade name: WA color Black A25, pigment content 15%, manufactured by Dainichi Seika Kogyo Co., Ltd.),
C. I. Pigment Green 7 [trade name: WA-S color Green, pigment content 8%, manufactured by Dainichi Seika Kogyo Co., Ltd.]
C. I. Pigment Violet 23 [trade name: Micropigmo WMVT-5, pigment content 20%, manufactured by Orient Chemical Co., Ltd.]
C. I. Pigment Yellow 83 [trade name: Emacol NS Yellow 4618, pigment content 30%, manufactured by Sanyo Color Co., Ltd.].

  As fluorescent pigments, synthetic resin fine particle fluorescent pigments in which various fluorescent dyes are formed into a solid solution in a resin matrix can be used. Other examples include metallic luster pigments, phosphorescent pigments, white pigments such as titanium dioxide, silica, and calcium carbonate, capsule pigments encapsulating a reversible thermochromic composition, capsule pigments encapsulating perfume and perfume.

As the solvent, water and, if necessary, a water-soluble organic solvent are used.
Examples of the water-soluble organic solvent include ethanol, propanol, butanol, glycerin, sorbitol, triethanolamine, diethanolamine, monoethanolamine, ethylene glycol, diethylene glycol, thiodiethylene glycol, polyethylene glycol, propylene glycol, butylene glycol, and ethylene glycol monomethyl. Ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, sulfolane, 2-pyrrolidone, N-methyl-2- Pyrrolidone, and the like.

  Furthermore, acrylic resin, styrene maleic acid copolymer, cellulose derivative, polyvinyl pyrrolidone, polyvinyl alcohol, dextrin and the like can be used as necessary, and can be used for fixing to a paper surface or imparting viscosity.

Furthermore, a shear thinning agent can be added.
By adding the shear thinning agent, it is possible to suppress the aggregation and sedimentation of the colorant and to suppress the bleeding of the handwriting.
Furthermore, when the writing instrument to be filled with the ink is in the form of a ballpoint pen, it prevents ink leakage from the gap between the ball and the tip when not in use, or the ink when the writing tip is left upward (upright state). Backflow can be prevented.
The viscosity of the ink composition to which the shear thinning agent is added is 20 to 300 mPa · s at a shear rate of 3.84 S ⁻¹ by an E-type rotational viscometer at 20 ° C., and It is preferable that the shear thinning index is 0.1 to 0.9.
By showing the above-mentioned viscosity range and shear thinning index, it is possible to further leak ink and prevent ink backflow.
The shear thinning index (n) is expressed by an empirical formula T = Kj ⁿ (K is a non-Newtonian viscosity coefficient) obtained from rheological measurement using a viscometer such as a shear stress value (T) and a shear rate value (j). It is a value calculated by fitting.

Examples of the shear thinning agent include xanthan gum, welan gum, succinoglycan (average molecular weight of about 1 to 8 million) whose constituent monosaccharide is an organic acid-modified heteropolysaccharide of glucose and galactose, 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, mainly composed of alkyl esters of methacrylic acid, thickening agent having gelling ability extracted from seaweed such as glucomannan, agar and carrageenan Sugars, benzylidene sorbitol and benzylidene xylitol or their derivatives, crosslinkable acrylic acid polymer, inorganic fine particles, polyglycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polio Shi polyoxyethylene alkyl ether-polyoxypropylene alkyl ethers, polyoxyethylene alkyl phenyl ether, nonionic HLB value, such as fatty acid amide is 8-12 surfactants, salts of dialkyl or dialkenyl sulfosuccinic acid. Examples thereof include a mixture of N-alkyl-2-pyrrolidone and an anionic surfactant, and a mixture of polyvinyl alcohol and an acrylic resin.
The shear thinning agent can be used in combination, and the polymer can be used as a resin.

When the ink composition of the present invention is used by filling a ballpoint pen, a metal soap, a nonionic surfactant having a long-chain alkyl group, a polyether-modified silicone oil, thiophosphorous acid tri (alkoxycarbonylmethyl ester), Thiophosphorous acid triesters such as phosphoric acid tri (alkoxycarbonylethyl ester), phosphoric acid monoester of polyoxyethylene alkyl ether or polyoxyethylene alkyl aryl ether, polyoxyethylene alkyl ether or phosphoric acid diester of polyoxyethylene alkyl aryl ether Alternatively, it is preferable to add a lubricant such as a metal salt, an ammonium salt, an amine salt, an alkanolamine salt or the like to give an effect of preventing wear of the ball seat.
In addition, inorganic salts such as sodium carbonate, sodium phosphate and sodium acetate, pH adjusters such as organic basic compounds such as water-soluble amine compounds, benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, diisopropylammonium nitrite, saponin, etc. Rust preventive agent, coalic acid, sodium salt of 1,2-benzthiazolin-3-one, sodium benzoate, sodium dehydroacetate, potassium sorbate, propyl paraoxybenzoate, 2,3,5,6-tetrachloro-4- (Methylsulfonyl) pyridine and other preservatives or antifungal agents, urea, nonionic surfactants, reduced or non-reduced starch hydrolysates, oligosaccharides such as trehalose, sucrose, cyclodextrin, glucose, dextrin, sorbit, man knit, Wetting agents such as pyrophosphate sodium, defoamers, may be used a dispersing agent, a fluorine based surfactant to improve ink permeability and nonionic surfactants.

The ink composition is put into practical use by filling a marking pen, a ballpoint pen, a brush pen, a fountain pen, or the like with a tip attached to a writing tip.
When filling the marking pen, the structure and shape of the marking pen itself are not particularly limited. For example, a fiber tip, felt tip, or plastic tip is attached to the writing tip and the fiber bundle accommodated inside the shaft tube is used. The ink occlusion body is impregnated with ink, the ink is supplied to the tip of the writing, the ink is directly stored inside the shaft cylinder, and the ink flow rate adjustment member consisting of a comb groove-like ink flow rate adjustment member or fiber bundle is interposed Examples include a marking pen having a structure in which ink is directly stored in the shaft cylinder and a predetermined amount of ink is supplied to the writing tip portion by a valve mechanism.
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, ink is stored directly inside the shaft cylinder, and there is an ink storage tube filled with the ink composition in the shaft cylinder, with a comb groove-shaped ink flow control member and an ink flow control member consisting of fiber bundles interposed The ink containing tube communicates with a tip having a ball attached to the tip, and a ballpoint pen having a structure in which a liquid stopper for backflow prevention is in close contact with the end face of the ink can be exemplified.

The ballpoint pen tip will be described in more detail. A tip formed by holding a ball in a ball holding portion obtained by pressing and deforming the vicinity of the tip of a metal pipe inward from the outer surface, or a metal material is cut by a drill or the like A chip formed by holding the ball in the ball holding part formed by the above, a chip provided with a resin ball receiving seat inside a metal or plastic chip, or a ball held by the chip is moved forward by a spring body Energized items can be applied.
The ball may be about 0.2 to 3 mm in diameter, such as cemented carbide, stainless steel, ruby, ceramic, resin, or rubber.
In addition, the writing instrument filled with the ink of the present invention includes those provided with a rolling mechanism such as a roller at the tip of the writing for forming a handwriting by the same rolling operation as that of the ball.

For example, a molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, or nylon is used as the ink storage tube that stores the ink composition.
Furthermore, by using a transparent, colored transparent, or translucent molded body as the ink containing tube, the ink color, the remaining amount of ink, and the like can be confirmed.
In addition to directly connecting the chip to the ink storage tube, the ink storage tube and the chip may be connected via a connecting member.
The ink storage tube may be a refill type in which the refill is accommodated in the shaft cylinder, or the shaft cylinder itself having a tip mounted on the tip is used as an ink container to directly fill the shaft cylinder with ink. May be.

The back end of the ink composition accommodated in the ink accommodating 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.

It is preferable to add a gelling agent to the nonvolatile liquid and / or the hardly volatile liquid to increase the viscosity to a suitable viscosity. The surface of the silica is hydrophobized, the surface is methylated fine particle silica, and aluminum silicate. , 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.
Note that the form of the writing instrument is not limited to that described above, and may be a twin-type writing instrument on which a pen body having a different form is mounted or a pen body on which different colors are derived is mounted.

The following table shows the composition of each example.

The contents of the raw materials in the table are explained according to the note numbers.
(1) Eisen Co., Ltd., trade name: Eosin GH 35% -L, active ingredient 35%
(2) Product name: Water Yellow 6C, manufactured by Orient Chemical Co., Ltd.
(3) Product name: Acid Red FB, manufactured by Daiwa Kasei Co., Ltd.
(4) Made by Orient Chemical Industry Co., Ltd., trade name: Water Blue 106L, 10% active ingredient
(5) Sanyo Color Co., Ltd., trade name: Sundai Super Black C, active ingredient 30%
(6) Daiichi Kogyo Seiyaku Co., Ltd., trade name: Prisurf AL, polyoxyethylene distyrenated phenyl ether phosphoric acid monoester and diester mixture (7) Zeneca Co., Ltd., trade name: Proxel XL-2 1,2-Benzisothiazoline-3-one (8) Shin-Etsu Silicone Co., Ltd., trade name: KF-6100
(9) Product name: KF-6104, manufactured by Shin-Etsu Silicone Co., Ltd.

Preparation of Ink Backflow Preventer Body In 85 parts of polybutene as a base oil, 15 parts of fatty acid amide as a thickener was added, and then kneaded with three rolls to obtain an ink backflow preventer body.

Preparation of ballpoint pen Each of the ink compositions obtained as described above was filled in a ballpoint pen refill fitted with one end of a polypropylene pipe with a stainless steel chip holding a ball having a diameter of 0.4 mm. After the ink backflow preventer was disposed, the ballpoint pen refill was incorporated into a shaft tube to produce a ballpoint pen.

Ink runoff test Ten ballpoint pens obtained as described above were prepared and written on a writing tester in accordance with JIS S6054 under the conditions of a load of 100 g, a writing speed of 4 m / min, and a writing angle of ° C. Ink consumption per 100 m (average value of 10) was calculated.
Handwriting test The handwriting obtained in the ink outflow test was visually observed.
Write-off test The number of ball-point pens that could not completely consume ink among the 10 ball-point pens was examined.
The test results are shown in the following table.

The criteria for the state of handwriting in the table are as follows.
○: A good handwriting can be formed.
(Triangle | delta): A handwriting becomes thin thinly as it writes.
▲: The handwriting becomes thinner as you write.
X: The repeated phenomenon that a handwriting becomes light according to writing and then becomes dark is seen.

Claims (4)

  A water-based ink composition for a writing instrument comprising at least a colorant, water, and polyglycerin-modified silicone.   The water-based ink composition for a writing instrument according to claim 1, comprising 0.01 to 2 parts by weight of the polyglycerin-modified silicone in the ink composition.   The water-based ink composition for a writing instrument according to claim 1 or 2, comprising a shear thinning agent.   A writing instrument in the form of a ballpoint pen containing the water-based ink composition for a writing instrument according to claim 3.