JP2009292056A - Writing utensil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a writing utensil capable of indefinitely forming a good handwriting without spoiling appearance and worsening color tone of the handwriting by generating color fading and browning of ink visually recognized from the outside in the writing utensil storing the ink in a shaft cylinder formed of a transparent material. <P>SOLUTION: The writing utensil stores an aqueous ink composition comprising at least a coloring agent, water, thiocyanuric acid and/or its salt and enables the ink to be visually recognized from the outside through the shaft cylinder. The writing utensil has a shape of a marking pen. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a writing instrument. Furthermore, the present invention relates to a writing instrument in which water-based ink is incorporated in a transparent shaft cylinder.

2. Description of the Related Art Conventionally, colorful writing instruments in which a shaft cylinder and an ink storage tube are formed of a transparent material, and ink compositions of various colors are stored therein are widely used.
When the ink composition housed in the writing instrument is exposed to light and the colorant fades or browns, the color tone of the ink that is visible through the writing instrument changes remarkably, so that the appearance different from the initial color tone appears. Product value is impaired by being visually recognized. Moreover, since the color tone of a handwriting will change a lot if fading advances, it will also lead to deterioration of product performance. In particular, when a colorant having a xanthene skeleton is used, fading is noticeable.
As a cause of fading of the colorant, it is conceivable that application of the colorant or additive generates active oxygen species by photosensitizing action, and the active oxygen species causes the colorant to fade.
In order to solve the above problems, attempts have been made to add ultraviolet absorbers such as benzophenone-based, salicylic acid-based, benzotriazole-based, and cyanoacrylate-based inks (for example, see Patent Documents 1 and 2). Absorbents are very poorly soluble in media and can be added only in small amounts, especially when used in water-based inks. The effect of improving light resistance could not be obtained.
JP-A 62-106971 JP 9-279080 A

  The present invention is a writing instrument that contains ink in a shaft cylinder made of a transparent material, and the color tone of the ink visually recognized from the outside may deteriorate or deteriorate the color tone of the handwriting due to fading or browning. Therefore, it is an object of the present invention to provide a writing instrument that can form a good handwriting permanently.

The present invention requires a writing instrument that incorporates a water-based ink composition containing at least a colorant, water, thiocyanuric acid and / or a salt thereof, and the ink is visible from the outside via a shaft cylinder.
Furthermore, it is a requirement that the colorant has a xanthene skeleton, that the ink is contained in a container having transparency that can be replaced, and that the ink is filled in a replaceable ink storage body.
Furthermore, it is a requirement that the writing instrument is in the form of a marking pen.

  According to the present invention, the ink contained in the ink cartridge, the refill or the like using the ink container or the ink filling material such as filling, or even the writing instrument configured to be visible directly from the outside. Therefore, it is possible to provide a writing instrument with a high commercial value that can form a good handwriting without causing fading or browning to impair the appearance, and without changing the color tone of the handwriting from the initial stage over the long term.

The present invention incorporates ink in a shaft cylinder using a visually recognizable member (transparent member), so that the color of the ink can be visually recognized from the outside (outside) through the shaft cylinder. It is a rich writing instrument.
In the writing instrument, since the ink is always exposed without being shielded, the ink tends to fade in the shaft cylinder over time. The color fading of the ink is a substance that generates active oxygen species contained in the ink (for example, a dye used as a colorant, resin particles containing the dye, a compound used as an additive, a compound having a phenolic hydroxyl group, a naphthalene derivative) , Acridine derivatives, benzothiazole derivatives, benzophenone derivatives, naphthoquinone derivatives, anthraquinone derivatives, etc.) are generated by photosensitizing action to generate reactive oxygen species, and the reactive oxygen species causes dyes and resin particles containing dyes to fade. It is. Therefore, the present application suppresses discoloration and browning of the colorant due to active oxygen species by using thiocyanuric acid or a salt thereof that has the function of capturing and removing the active oxygen species, and maintains a good quality state for a long time. It is a writing instrument that can be maintained.
The active oxygen species refers to singlet oxygen, superoxide anion radical, hydrogen peroxide, hydroxy radical, alkyl radical, hydroperoxide radical, and the like.

As a form of the writing instrument, a ballpoint pen or a marking pen (including a fountain pen and a brush pen) provided with a shaft cylinder in which ink can be visually recognized from the outside and equipped with various pen tips at the writing tip part is used.
The structure and shape of the ballpoint pen itself are not particularly limited, for example, a structure in which ink is impregnated into a fiber bundle housed in a shaft cylinder and ink is supplied to a pen tip (ballpoint pen tip), A structure in which ink is directly stored in the shaft cylinder and an ink flow rate adjusting member composed of a comb groove-like ink flow rate adjusting member or a fiber bundle is interposed between the pen tip and the pen tip is connected directly or via a connecting member. The shaft cylinder can contain a liquid stopper for preventing ink and backflow, and the ink storage pipe can contain a ball pen refill that contains a liquid stopper for preventing ink and backflow in the shaft cylinder. Cap type, retractable type Any of these can be used. In addition, as a retractable type, the form which accommodates multiple said refills may be sufficient.
The structure and shape of the marking pen itself are not particularly limited. For example, a pen tip (marking pen tip) is attached to the writing tip, and ink is applied to an ink occlusion body composed of a fiber bundle housed inside the shaft cylinder. A structure for impregnating and supplying ink to the nib, a structure in which ink is directly stored in the shaft cylinder, and an ink flow rate adjusting member composed of a comb groove-like ink flow rate adjusting member or a fiber bundle is interposed between the pen tip, 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 pen tip by a valve mechanism can be used, and either a cap type or a retractable type can be used.
In addition, as a fountain pen, ink is stored directly in the shaft tube, and a structure in which an ink flow rate adjusting member composed of a comb groove-like ink flow rate adjusting member or a fiber bundle is interposed between the fountain pen type nib, Examples include a structure in which a cartridge containing ink is housed and an ink flow rate adjusting member having a comb groove shape or a fiber bundle is interposed between a fountain pen nib.

The ball pen tip used as the nib 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. A chip formed by holding a ball in a ball holding portion formed by cutting with a drill or the like, a chip provided with a resin ball receiving seat inside a metal or plastic chip, or a ball held by the chip What was urged | biased ahead with the spring body etc. can be applied.
Moreover, the said balls can apply about 0.1-3 mm diameter things, such as a cemented carbide alloy, stainless steel, a ruby, a ceramic, resin, rubber | gum.
Note that the writing instrument of the present invention includes one provided with a rolling mechanism such as a roller at the tip of the writing, which forms a handwriting by the same rolling action as the ball.
The marking pen tip used as the pen tip will be described in more detail. Examples include a fiber tip, a felt tip, and a plastic tip, which are applied in the form of a shell type, a chisel type, a flat type, a brush pen type, and the like.
Further, as the fountain pen type nib, specifically, a metal plate such as a stainless steel plate or a gold alloy plate is cut into a taper taper shape, bent or curved, or resin-molded into a nib shape is applied. it can. The fountain pen-type pen body can be provided with a slit at the center or a ball at the tip.

As the shaft cylinder, ink cartridge, and ink storage tube (refill pipe) for storing ink, for example, a transparent molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, nylon, polycarbonate, and ABS is used.
The transparency includes colored transparency, translucent, and colored translucent, and can confirm the ink color, the remaining amount of ink, and the like.
The transparent shaft cylinder, ink cartridge, and ink storage tube have transparency as a whole, and also have a transparent part so that the remaining amount of ink can be visually recognized. Also good.

Also, it does not take the form of directly containing ink in the shaft cylinder, and ink is contained in a transparent container such as an ink cartridge or an ink container tube, and further an ink occlusion body (fiber bundle covered with a transparent skin). In the case of taking the form of being filled and accommodated in the outer shaft, it is also possible to have a structure in which these transparent accommodating bodies and ink occlusion bodies can be exchanged.
In that case, since the ink flows out into the market alone as a replacement ink in a state where the ink is visible, although it is in a more disadvantageous state against the fading of the ink, in the configuration of the present application, the fading and deterioration of the ink can be reliably suppressed. It will be a thing. When an exchangeable ink container (occlusion body) is used, the outer shaft is not limited to having transparency and may be opaque.
In addition, the replenishment ink in which the ink for replenishing the writing instrument is contained in the transparent soft resin container flows out to the market as a single unit. In the ink used, fading can be suppressed.

Furthermore, the form of the writing instrument is not limited to that described above, and it may be a writing instrument of a double-headed form in which a pen tip having a different form is attached or a pen tip for deriving inks of different colors is attached.
As the double-headed writing instrument, a partition wall is provided in a transparent shaft tube, and a writing tip is fixed to both ends of the shaft tube directly or via a relay member, respectively, and water-based inks having different colors in the shaft tube In a writing instrument or a shaft tube containing the ink directly with the ink occlusion body, 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 color tone. Examples of writing instruments containing different water-based inks.

The water-based ink composition incorporated in the writing instrument contains at least a colorant, water, thiocyanuric acid and / or a salt thereof.
By adding the thiocyanuric acid or a salt thereof to the ink, fading or browning of the colorant due to the active oxygen species generated in the ink can be suppressed.
Examples of the salt include alkali metal salts such as lithium, sodium and potassium, alkaline earth metal salts such as calcium and barium, metal salts such as magnesium and aluminum, and amine salts such as alkanolamine and ammonia.

The thiocyanuric acid and its salt can be added in an amount of 0.05 to 5% by weight, preferably 0.1 to 3% by weight, in the ink composition.
If it is 0.05% by weight or less, it is difficult to obtain the desired fading-inhibiting effect, and even if it exceeds 5% by weight, no further fading-inhibiting effect can be obtained. do not do.

As the colorant, 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, direct dyes, inorganic pigments such as carbon black and ultramarine blue, and copper Organic pigments such as 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.
As for the dye, a colorant having a xanthene skeleton having a halogen group (especially a dye) is likely to generate active oxygen species due to photosensitization, and the dye itself is fading and it is difficult to maintain the initial color tone. Further, when other dyes are used in combination, the active oxygen species act on the fading of the other dyes to cause further fading.

Among the colorants, examples of the colorant having a xanthene skeleton that is easily discolored by active oxygen species include Acid Red 87 (Eosin), Acid Red 92 (Phloxine), Acid Red 51 (Erythrosin), and Acid Red 94 (Rose). Bengal), Acid Red 388, Acridine Red (C.I. 45000), Rhodamine 110, Rhodamine 123, Rhodamine 6G (C.I. Basic Red 1), Rhodamine 6G Extra, Rhodamine 116, Rhodamine B (C.I. 45170) ), Tetramethylrhodamine perchlorate, rhodamine 3B, rhodamine 19, sulforhodamine, pyronin G (CI.45005), rhodamine S (CI.45050), rhodamine G (CI.45150), ethyl Rhodamine B ( I.45175), rhodamine 4G (C.I.45166), rhodamine 3GO (C.I.45215), sulforhodamine G and the like, and colored resin particles containing the dye (specifically, xanthene series) And pigments such as rhodamine lake 6G, rhodamine lake B (CI 45170: 2), rhodamine lake Y (CI 45160: 1), and the like.
Each colorant can be used singly or in combination of two or more, and can be added in the range of 0.1 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.

By adding a polymer flocculant in the ink, the flocculant causes a loose bridging action between pigments (resin particles containing dye), and exhibits a loose agglomeration state. Ink showing such a loose aggregation state does not cause separation of the pigment in the capillary gap between the ink occlusion body (batting) made of a fiber bundling body and the marking pen body made of a resin bundle of fibers.
Therefore, it is possible to obtain a marking pen having a storage performance equivalent to that of a marking pen filled with a dye ink by suppressing the occurrence of darkening or lightening of the handwriting by separating the pigment by standing upright or inverted.
As the water-soluble polymer flocculant, a water-soluble polymer compound is used, and examples include water-soluble polysaccharides such as tragacanth gum, guar gum, pullulan, cyclodextrin, and cellulose derivatives, polyvinyl pyrrolidone, and polyethylene oxide.
Specific examples of the cellulose derivative include methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose and the like.

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 filling the ink is not used, or the writing tip can be faced up (upright state). When the ink is left as it is, it is possible to prevent the ink from flowing backward and to prevent the 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, benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, diisopropylammonium nitrite, saponin and other rust preventives, coalic acid, sodium salt of 1,2-benzthiazolin-3-one, sodium benzoate, dehydro as necessary Preservatives or antifungal agents such as sodium acetate, potassium sorbate, propyl paraoxybenzoate, 2,3,5,6-tetrachloro-4- (methylsulfonyl) pyridine, urea, nonionic surfactants, reduced or non- Reduced starch hydrolyzate, disaccharides such as trehalose, oligosaccharides, sucrose, cyclodextrin, glucose, dextrin, sorbit, mannitol, sodium pyrophosphate and other wetting agents, antifoaming agents, dispersants, ink permeability Improved fluorosurfactant It may be used nonionic surfactants.
Moreover, an acrylic resin, a styrene maleic acid copolymer resin, polyvinyl alcohol, etc. can also be used for the adhering property to a paper surface, and viscosity provision as needed.

When the water-based ink composition is incorporated in an ink storage tube or a shaft tube, an ink backflow preventer can be filled at the rear end of the ink.
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 following table shows the compositions of the inks incorporated in the writing instruments of Examples and Comparative Examples. In addition, the part in a table | surface shows a weight part.

The contents of the raw materials in the table will be described along the note numbers.
(1) Eisen Hodogaya Co., Ltd., Acid Red 87, Trade name: Eosin GH 35% -L
(2) Eisen Hodogaya Co., Ltd., Acid Red 92, trade name: Phloxine (3) Sinloihi Co., Ltd., trade name: SF501 Pink, solid content 30%
(4) Arch Chemicals Japan, trade name: Proxel XL-2
(5) Product name: Prisurf AL, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.
(6) Daiichi Kogyo Seiyaku Co., Ltd., trade name: F-6212
(7) Made by Sanki Co., Ltd., trade name: Leozan (8) Made by Hokuko Sangyo Co., Ltd., trade name: Hokuside R-150
(9) Kyowa Hakko Co., Ltd., trade name: Glutathione (10) Clariant Japan, trade name: SANDUVOR 3225 DISP
(11) Product name: SANDUVOR PT21 DISP, manufactured by Clariant Japan

Preparation of ink cartridge type marking pen Each ink composition prepared by mixing and stirring the compositions of Examples 1-2 and Comparative Examples 1-4, stirring at 400 ° C. for 1 hour with a disper at 25 ° C., and filtering. Was accommodated in a transparent cartridge container made of polyethylene, and a stopper was fixed to prepare an ink cartridge.
After that, the obtained ink cartridge contains a synthetic resin pen core that temporarily stores ink in the ink storage part according to the change in internal and external pressure inside the transparent shaft, and the tip of the pen core is a fountain pen type A fountain pen type marking by installing a pen tip and a writing instrument main body with an ink guide core for guiding ink from the ink storage section to the pen tip. A pen (cap type) was obtained.

Preparation of marking pen After mixing and stirring the compositions of Examples 3 and 4 and Comparative Examples 5 and 6, the ink compositions prepared by stirring at 25 ° C. with a disper at 400 rpm for 1 hour and filtering, A fiber sizing ink occlusion body coated with a synthetic resin film with polyester sliver is impregnated and accommodated in a transparent shaft cylinder, and a chisel-type fiber pen body is attached to the tip of the shaft cylinder to obtain a filling type marking pen (cap type) It was.

Preparation of Ballpoint Pen In the compositions of Example 5 and Comparative Example 7, after adding other than the shear thinning agent to water and mixing and stirring, add the shear thinning agent, and at 25 ° C. with a disper. Each ink was prepared by stirring at 400 rpm for 1 hour and filtering.
Further, 1.5 parts of fatty acid amide as a thickener was added to 98.5 parts of polybutene as a base oil, and then kneaded with three rolls to obtain an ink backflow preventer.
A stainless steel chip holding a cemented carbide ball having a diameter of 0.3 mm was filled with the ink of Example 5 and Comparative Example 7 into a ballpoint pen refill fitted to one end of a transparent polypropylene pipe, and the rear end was After arranging the ink backflow prevention body, the ballpoint pen refill was incorporated into a transparent shaft cylinder (cap type) to prepare a refill type ballpoint pen.

The following tests were conducted using each marking pen and ballpoint pen.
Light Resistance Test After marking each marking pen and ballpoint pen with a xenon light resistance tester (suga tester, xenon lamp applied) at an irradiation intensity of 180 W / m ^{2 for} 20 hours, the color tone of ink visible through the outside Compared with the initial stage (appearance test).
Writing test Using each writing instrument (12) for which the light resistance test was performed, the color tone of the handwriting when writing on paper was confirmed.
The test results are shown in the following table.

In addition, the evaluation regarding the symbol of the test result in a table | surface is as follows.
Light resistance test ○: No change was observed in the color tone of the ink compared to the initial stage.
X: Yellowing (discoloration) compared with the initial stage.
Written test ○: There was no change in handwriting compared to the initial stage.
X: Yellowing (discoloration) compared with the initial stage.

Claims (5)

  A writing instrument comprising a water-based ink composition containing at least a colorant, water, thiocyanuric acid and / or a salt thereof, wherein the ink is visible from the outside through a shaft cylinder.   The writing instrument according to claim 1, wherein the colorant has a xanthene skeleton.   The writing instrument according to claim 1 or 2, wherein the ink is incorporated in a container having transparency that can be exchanged.   The writing instrument according to claim 1 or 2, wherein the ink is filled in a replaceable ink occlusion body.   The writing instrument according to claim 1, wherein the writing instrument is in the form of a marking pen.