JP2007119530A - Writing tool - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a writing tool having therein a water-based ink whose composition is not affected and which is not rotted by the growth of fungi or the proliferation of microorganisms and does not fade the color of the ink, even when a transparent axial cylinder is used. <P>SOLUTION: This writing tool is characterized by having a water-based ink composition comprising water, a rhodamine-based colorant, and p-chloro-m-cresol in a transparent axial cylinder. The p-chloro-m-cresol is preferably contained in an amount of 0.001 to 0.5 wt.% based on the total amount of the ink composition. The writing tool is characterized by having a comb groove-like ink-holding member in the axial cylinder. An ink-occluding member for be soaked in the ink is disposed in the axial cylinder. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a writing instrument. More specifically, the present invention relates to a writing instrument that has excellent anti-mold properties and can maintain the color developability of ink without causing discoloration due to ultraviolet rays.

Conventionally, in a water-based ink composition for writing instruments in which water is the main solvent, wrinkles have occurred over time, or microorganisms have propagated and the ink has spoiled. In particular, when natural polymers or polysaccharides are added to the ink composition for the purpose of improving the writing performance, straws and microorganisms tend to propagate more easily. Therefore, it is indispensable to add an antibacterial substance, that is, an antifungal agent, to the ink composition for the purpose of preventing the growth of the wrinkles and microorganisms.
As the compound used for the antifungal agent, coalic acid (phenol), cresol, 1,2-benzisothiazolin-3-one and the like are disclosed (for example, see Patent Documents 1 to 3).
Of these antifungal agents, since carboxylic acid and cresol are volatile, a writing instrument (in the shaft cylinder) provided with a comb groove-shaped ink retaining member (so-called pen core), a fiber converging body (so-called batting), etc. (A writing instrument with a structure with many spaces that do not come into contact with ink) can exhibit anti-fouling performance, but when it is built in a writing instrument that uses a transparent shaft, radicals are generated by light (visible light or ultraviolet light). There is a risk of discoloring the dye or the colored resin particles containing the dye. In addition, 1,2-benzisothiazolin-3-one cannot exhibit antifungal properties depending on the pH of the ink, and may itself be insolubilized and deposited, and has low volatility.
Japanese Patent Laid-Open No. 5-140498 JP-A-2-67376 Japanese Patent Laid-Open No. 11-43628

  The present invention is intended to solve the problems of the conventional writing instruments described above, and without causing adverse effects on the ink composition, it may cause spoilage and spoilage due to the growth of microorganisms even after long-term storage. In addition, the present invention provides a writing instrument incorporating a water-based ink in which fading of ink is unlikely to occur even when a transparent cylinder whose inside can be visually recognized is used.

The present invention requires a writing instrument in which a water-based ink composition containing water, a rhodamine colorant, and p-chloro-m-cresol is incorporated in a transparent shaft cylinder.
Furthermore, the p-chloro-m-cresol is contained in an amount of 0.001 to 0.5% by weight in the total amount of the ink composition, the shaft cylinder is provided with a comb groove-shaped ink retaining member, It is a requirement that an ink occlusion body impregnated with ink is disposed in the shaft cylinder.

  The present invention is stable over time without adversely affecting the ink composition, exhibits a sufficient antifungal effect, hardly causes discoloration or fading of ink due to light from the outside, and the inside of the shaft tube is visually recognized. Possible writing instruments can be provided.

  The writing instrument of the present invention does not cause discoloration of ink due to ultraviolet rays even when a water-based ink containing a rhodamine-based colorant and p-chloro-m-cresol is contained in a transparent shaft cylinder. It can exhibit an excellent anti-mold effect.

The p-chloro-m-cresol is an antiseptic / antifungal agent and exhibits an excellent antiseptic / antifungal effect for water-based inks without inhibiting the coloring of colorants (particularly rhodamines).
The p-chloro-m-cresol is contained in an amount of 0.001 to 0.5% by weight, preferably 0.001 to 0.3% by weight, based on the total amount of the ink composition.
If it is less than 0.001% by weight, sufficient antiseptic / antifungal properties cannot be exhibited, and more than 0.5% can be contained, but since the effect does not change, no further addition is required. .
In addition, other antiseptic / antifungal agents can be used in combination with p-chloro-m-cresol.

  Examples of the rhodamine colorant include rhodamine 110, rhodamine 123, rhodamine 6G (CI Basic Red 1), rhodamine 6G extra, rhodamine 116, rhodamine B (CI. 45170), tetramethylrhodamine perchlorate. , Rhodamine 3B, rhodamine 19, sulforhodamine, pyronin G (CI.45005), rhodamine S (CI.45050), rhodamine G (CI.45150), ethylrhodamine B (C.I.45175) Rhodamine 4G (C.I. 45166), rhodamine 3GO (C.I. 45215), sulforhodamine G, Acid Red 52, Acid Red 289, Acid Red 388, Acridine Red (C.I. 45000), etc. Dye and coloring containing the dye Fat particles (specifically, a pigment obtained by solidifying a rhodamine dye in a resin matrix), rhodamine lake 6G, rhodamine lake B (C.I. 45170: 2), rhodamine lake Y (C.I. 45160: Examples thereof include rhodamine pigments such as 1), which are used alone or in combination.

If desired, a general-purpose colorant can be used in combination with the rhodamine colorant.
As general-purpose colorants, all dyes and pigments that can be dissolved or dispersed in an aqueous medium can be used. Various dyes such as acid dyes, basic dyes, and direct dyes, inorganic pigments such as carbon black and ultramarine, Organic pigments such as copper phthalocyanine blue and benzidine yellow, and water-dispersed pigment products that are finely and stably dispersed in an aqueous medium in advance using a surfactant or a resin are used.
Further, a synthetic resin fine particle-shaped fluorescent pigment in which various fluorescent dyes are formed into a solid solution in a resin matrix, a white pigment such as titanium dioxide, a metal powder such as aluminum, a natural mica, a synthetic mica, alumina, and a glass piece. A pearl pigment whose surface is coated with a metal oxide such as titanium dioxide, a cholesteric liquid crystal-type glitter pigment, a microcapsule pigment encapsulating a reversible thermochromic composition, and a dye or pigment together with the reversible thermochromic composition. It is also possible to use a thermochromic pigment such as a microcapsule pigment encapsulating.
Each colorant may be used alone or in combination of two or more, and is used in the range of 1 to 30% by weight, preferably 2 to 15% by weight in the ink composition.

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.
Specific examples of the water-based ink used in the present invention include a shear-thinning ink containing a shear-thinning agent, a cohesive ink obtained by suspending a pigment in a gentle aggregation state with a water-soluble polymer flocculant, and a viscosity of A low viscosity ink of about several mPa · s can be mentioned.

When the ink is filled in a writing instrument having an ink occlusion body (batting) made of a fiber bundling body or a marking pen body made of a resin binder of fibers, a capillary flocculant is added by adding a polymer flocculant to the ink. Separation of the colorant at can be suppressed. This is because the aggregating agent causes a loose bridging action between the pigments and exhibits a loose agglomerated state, and the darkening or lightening of the handwriting due to long-term standing of the writing instrument in an upright or inverted state is caused. It can be suppressed.
As the water-soluble polymer flocculant, a nonionic or anionic water-soluble polymer compound is used, and examples thereof include water-soluble polysaccharides such as polyvinylpyrrolidone, polyethylene oxide, and cellulose.

In addition, by adding a shear thinning agent to the ink, ink leakage from the gap between the ball and the tip can be prevented when the ballpoint pen that fills the ink is not used, or the writing tip is directed upward (upright state) ), It is possible to prevent backflow of ink and to prevent aggregation and sedimentation of the pigment.
The viscosity of the ink composition added with the shear thinning agent is 200 to 3000 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 0.6.
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 by 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, alka gum, guar gum, locust bean gum and A gel having a gelling ability extracted from seaweeds such as glucomannan, agar and carrageenan, polymers having a molecular weight of 100,000 to 150,000 mainly composed of derivatives thereof, hydroxyethyl cellulose, alginic acid alkyl esters, and alkyl esters of methacrylic acid. Viscous polysaccharides, benzylidene sorbitol and benzylidene xylitol or derivatives thereof, crosslinkable acrylic acid polymer, inorganic fine particles, polyglycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester , Polyoxyethylene alkyl ether, polyoxypropylene alkyl ether, polyoxyethylene alkylphenyl ether, fatty acid amide and other nonionic surfactants having an HLB value of 8 to 12, salts of dialkyl or dialkenylsulfosuccinic acid, N-alkyl Examples thereof include a mixture of -2-pyrrolidone and an anionic surfactant, and a mixture of polyvinyl alcohol and an acrylic resin.

  Further, when the ink is incorporated into a ballpoint pen for practical use, a higher fatty acid such as oleic acid, a nonionic surfactant having a long chain alkyl group, a polyether-modified silicone oil, a thiophosphorous acid tri (alkoxycarbonylmethyl ester) And thiophosphorous acid triesters such as thiophosphorous acid tri (alkoxycarbonylethyl ester), polyoxyethylene alkyl ether or polyoxyethylene alkyl aryl ether phosphoric acid monoester, polyoxyethylene alkyl ether or polyoxyethylene alkyl aryl ether It is preferable to add a lubricant such as phosphoric acid diesters or their metal salts, ammonium salts, amine salts, alkanolamine salts and the like to impart an effect of preventing wear of the ball seat.

In addition to the above components, pH adjusters such as inorganic salts such as sodium carbonate, sodium phosphate and sodium acetate, organic basic compounds such as water-soluble amine compounds, benzotriazole and its derivatives, tolyltriazole, dicyclohexylammonium as necessary Nitrite, diisopropylammonium nitrite, sodium thiosulfate, saponin and other rust preventives, 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, metal soaps, polyalkylene glycols, fatty acid esters, ethylene oxide addition type cationic activators, phosphoric acid based activators, Thiocarbamine Salt, lubricant such as dimethyldithiocarbamate, ascorbic acid, ascorbic acid derivative, α-tocopherol, catechin, catechin derivative, synthetic polyphenol, phosphonate, phosphinate, sulfite, sulfoxylate, dithionite, Antioxidants such as thiosulfate, thiourea dioxide, formamidinesulfinic acid, glutathione, wetness such as urea, cyclodextrin, sorbit, mannitol, sucrose, glucose, reduced or non-reduced starch hydrolysates, sodium pyrophosphate Agent, defoaming agent such as dimethylpolysiloxane, dispersing agent, fluorine-based surfactant that improves ink permeability, nonionic surfactant, surfactant that improves wettability to pen core surface, etc. May be.
If necessary, acrylic resin, styrene maleic acid copolymer resin, polyvinyl pyrrolidone, polyvinyl alcohol, dextrin and the like can be used for fixing to the paper surface and imparting viscosity.

The ink is put into practical use by filling a marking pen or ballpoint pen with a tip attached to the 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, plastic tip is attached to the writing tip, and the fiber bundle contained in the shaft cylinder is used. The ink occlusion body is impregnated with ink, the ink is supplied to the writing tip, the ink is stored directly inside the shaft cylinder, and an ink flow rate adjusting member consisting of a comb groove-shaped ink storage member and a 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, structure in which ink is directly stored in the shaft cylinder, and an ink flow rate adjusting member consisting of a comb groove-shaped ink storage member and a 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.
In particular, as a writing instrument of the present invention, a writing instrument having a structure with a large space that does not come into contact with ink in the shaft cylinder, for example, an ink occlusion body (batting) made of a fiber bundle housed in the shaft cylinder is impregnated with ink, and the writing tip Excellent antifouling performance can be exhibited even in a structure in which ink is supplied to the part or a structure in which ink is directly stored in the shaft cylinder and a comb groove-shaped ink storage member (pen core) is interposed.

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 0.1 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.

The shaft cylinder and the ink storage tube for containing ink are made of a transparent material, for example, a molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, polycyclohexane terephthalate, polycarbonate, polymethylpentene, and nylon. Is used.
The transparency refers to a state in which the inside of the shaft cylinder can be confirmed, such as ink color and ink remaining amount, including colored transparent, translucent, and colored translucent.
In addition, the transparent shaft cylinder or the ink containing tube may have transparency so that the remaining amount of ink can be visually recognized.
In addition, when the writing instrument is configured to accommodate the ink storage tube in the shaft tube, it is preferable to provide a transparent portion in any case so that the ink inside 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.

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.

The form of the writing instrument of the present invention is not limited to that described above, and may be a double-headed writing instrument on which a pen body having a different form or a pen body for deriving different color tones is attached.
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.

The ink composition of the present invention and the ink composition of the comparative example are shown below.
In addition, the number in a mixing | blending shows a weight part.

The contents of the raw materials in the table are explained according to the note numbers.
(1) Nippon Fluorescent Chemical Co., Ltd., trade name: Lumicol NKW-3907E, solid content 33.5%
(2) Product name: Lumicol NKW-3904E, solid content 33.5%, manufactured by Nippon Fluorescent Chemical Co., Ltd.
(3) Product name: Rhodamine B, manufactured by Sumitomo Chemical Co., Ltd.
(4) Product name: Brilliant Blue FCF, manufactured by Hodogaya Chemical Co., Ltd.
(5) Product name: Nikkor PBC-34 manufactured by Nikko Chemicals Co., Ltd.

Preparation of Ink Each raw material of the above Examples and Comparative Examples was mixed and stirred with a disper at 40 ° C. for 2 hours to obtain a water-based ink composition for writing instruments.

Production of writing instrument 1 Each ink was stored in a liquid state in a transparent shaft cylinder made of polycarbonate resin, a polyester fiber resin processing pen body was provided at the tip of the shaft cylinder, and a cap was attached to obtain a marking pen.
In addition, a comb groove-shaped ink storage member is provided at the rear part of the pen body in the shaft cylinder.

Preparation of writing instrument 2 A fiber bundling body is disposed in a transparent shaft cylinder made of polypropylene resin, the fiber bundling body is impregnated with each of the inks, a polyester fiber resin processing pen body is provided at the end of the shaft cylinder, and a cap is provided. A marking pen was obtained by mounting.

  For the ink compositions and writing instruments 1 and 2 obtained in Examples and Comparative Examples, the antifungal and light resistance tests were performed by the following methods.

Antifungal test 1
According to the Japanese Industrial Standard (JIS Z 2911), the initial stage and the water-based ink composition after 14 days at 30 ° C. were tested.
Antifungal test 2
The wrinkles used in JIS Z 2911 were added to the ink for each writing instrument, and the situation inside the writing instrument when 90 days passed at 30 ° C. was confirmed.
Light Resistance Test Each writing instrument was exposed to sunlight (seven days facing south) according to JIS L 0841, and the color tone of the appearance and the handwriting written on the paper with the cap removed were compared with the initial writing.
The results of each test are shown in the following table.

The explanation about the test result evaluation symbols in the table is as follows.
Antifungal test 1
○: There is a prevention circle.
X: There is no inhibition circle and wrinkles are generated in the water-based ink composition.
Antifungal test 2
○: No wrinkle occurred in any writing instrument.
X: Wrinkles are generated in the comb groove or the shaft tube.
Light resistance test ○: None of the writing instruments showed any change compared to the initial stage.
X: Significant color resistance and browning were observed compared to the initial stage.

Claims (4)

  A writing instrument in which a water-based ink composition containing water, a rhodamine-based colorant and p-chloro-m-cresol is incorporated in a transparent shaft cylinder.   The writing instrument according to claim 1, comprising 0.001 to 0.5% by weight of the p-chloro-m-cresol in the total amount of the ink composition.   The writing instrument according to claim 1, wherein a comb groove-shaped ink storage member is provided in the shaft cylinder.   The writing instrument according to claim 1, wherein an ink occlusion body impregnated with ink is disposed in the shaft cylinder.