JP2007083433A - Discoloring ball-point pen and writing utensil set employing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discoloring ball-point pen in which a contained discoloring liquid can be stably used to the last without developing troubles such as blur in a holograph, the scattering of a tip or the like at the use of an inner wadding type applicator with the fibrous tip and also can be easily painted into details, and a writing utensil set employing thereof. <P>SOLUTION: The discoloring ball-point pen formed by containing the discoloring liquid which includes at least water and a reducing agent and decolorizes or discolors an image formed with an ink including a dye decolorized or discolored by a reducing action, and a liquid plug arranged in a contact state behind the discoloring liquid within a housing tube attached with a ball-point pen tip directly or through a relay member and the writing utensil set composed of the discoloring ball-point pen and a writing utensil containing an ink including the dye decolorizing or discoloring by the reducing action or an ink including a coloring agent, which is neither decolorized nor discolored by the reducing action are dealt. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a color-changing ballpoint pen and a writing instrument set using the same. More specifically, the present invention relates to a discoloration ballpoint pen that contains a discoloration liquid that discolors or discolors an image formed by an ink containing a dye that is decolorized or discolored by a reducing action, and a writing instrument set using this ballpoint pen.
In the present invention, “front” refers to the pen tip side, and “rear” refers to the receiving tube side.

2. Description of the Related Art Conventionally, a writing instrument containing an ink containing a dye that is decolored or discolored by a reducing action has been used, and a discoloring applicator used for decoloring or discoloring a handwriting formed by the writing instrument as necessary. (For example, refer to Patent Documents 1 and 2).
The applicator for discoloration is an applicator provided with a fiber nib and containing a cotton pad impregnated with a discoloration liquid. For this reason, if the remaining amount of the color changing liquid impregnated in the batting becomes small, it becomes difficult to induce a sufficient amount of the color changing liquid to the pen tip, and thus fading is likely to occur when applied (written).
In addition, since a fiber tip is used as the nib, it is not suitable for erasing details, and the tip may be broken due to long-term use.
Japanese Examined Patent Publication No. 62-28834 JP 2004-122491 A

  The present invention solves the above-described conventional problems, that is, it causes blurring of handwriting, chipping, etc., which becomes a problem when using an applicator such as a filling type using fiber chips. Therefore, the present invention provides a color changing ballpoint pen that can be used up stably to the end and can be easily applied to details, and a writing instrument set using the same.

The ballpoint pen for discoloration of the present invention comprises at least water that discolors or discolors an image formed with an ink containing a dye that discolors or discolors by a reducing action in a storage tube in which a ballpoint pen tip is attached directly or via a relay member. And a color changing liquid containing a reducing agent and a liquid stopper disposed in contact with the rear of the color changing liquid.
Furthermore, 3 to 30% by weight of a reducing agent is contained in the total amount of the color-changing liquid, the color-changing liquid contains a phosphate ester surfactant, and the color-changing liquid is decolored or discolored by a reducing action. It is a requirement to include a colorant that does not occur.
Further, at the rear end of the color-changing ballpoint pen, a double-headed shape is provided by providing a writing instrument containing an ink containing a dye that is decolored or discolored by a reducing action, or an ink containing a colorant that is not decolored or discolored by a reducing action. It is a requirement that
Furthermore, a writing instrument set comprising the discoloring ballpoint pen and an ink containing a dye that is decolored or discolored by a reducing action, or a writing instrument containing a colorant that does not lose or discolor by a reducing action is required. .

  According to the present invention, a discoloration ballpoint pen that can stably use up a built-in discoloration solution to the end without fading of handwriting or chipping of a chip, and can be easily applied to details, and the ballpoint pen The writing instrument set used can be provided.

  The ballpoint pen for color change of the present invention comprises a color change solution and a liquid stopper in a housing tube to which a ballpoint pen tip is attached directly or via a relay member.

As the color changing liquid, a solution in which a reducing agent is added to an aqueous medium is used.
Specific examples of the reducing agent include sodium sulfite, potassium sulfite, lithium sulfite, calcium sulfite, ammonium sulfite, zinc sulfite, sodium thiosulfate, potassium thiosulfate, ammonium thiosulfate, sodium hypochlorite, hydrosulfite and the like. In view of safety and discoloration or decoloring performance, sulfites such as sodium sulfite and potassium sulfite are preferably used.
The reducing agent is contained in an amount of 3 to 30% by weight, preferably 10 to 25% by weight, based on the total amount of the color changing liquid. If it is 3% by weight or less, sufficient erasability cannot be imparted, and if it is added in an amount of 30% by weight, sufficient erasability and discoloration are satisfied, so no further addition is required.

Moreover, an organic solvent, a coloring agent, and various additives can be mix | blended with the said discoloration liquid as needed.
By using a dye or pigment that is difficult to be discolored by the reducing agent as the colorant, the color change liquid can be colored and the visibility is excellent.

In particular, it is preferable to add a surfactant as the additive. Addition of the surfactant increases the penetrability to the paper surface when applied, and can more reliably discolor or decolor the handwriting with the color-changing ink, and more reliably suppress line skipping during writing. .
The surfactant is suitably used in the range of 0.05 to 5% by weight, preferably 0.1 to 2% by weight, based on the total amount of the color changing liquid. If it is 0.05% by weight or less, a sufficient effect for suppressing line jumping cannot be obtained, and if it is added at 5% by weight, a sufficient effect for suppressing line jumping can be imparted, so no further addition is required.

  As the surfactant, general-purpose ones such as anionic, nonionic, amphoteric, phosphate ester, and fluorine are applicable as long as they are soluble in an aqueous solution having a high salt concentration and strong alkalinity. A phosphoric acid ester-based material is preferably used.

Examples of the phosphate ester-based surfactant include alkali metal salts of phosphoric acid monoesters of polyoxyethylene alkyl ether, alkali metal salts of phosphoric acid monoesters of polyoxyethylene alkylphenyl ether, and phosphoric acid of polyoxyethylene alkyl ether There are alkali metal salts of diesters and alkali metal salts of phosphoric acid diesters of polyoxyethylene alkylphenyl ether. Examples of the alkali metal include sodium and potassium. Also, polyoxyethylene alkyl ether phosphoric acid monoester amine salt, polyoxyethylene alkylphenyl ether phosphoric acid monoester amine salt, polyoxyethylene alkyl ether phosphoric acid diester amine salt, polyoxyethylene alkylphenyl ether Examples thereof include amine salts of phosphoric acid diesters. Also, alkanolamine salt of polyoxyethylene alkyl ether phosphoric acid monoester, alkanolamine salt of polyoxyethylene alkylphenyl ether phosphoric acid monoester, alkanolamine salt of polyoxyethylene alkyl ether phosphoric acid diester, polyoxyethylene Examples thereof include alkanolamine salts of phosphoric acid diesters of alkylphenyl ethers.
Specifically, “Phosphanol PE-510” manufactured by Toho Chemical Industry Co., Ltd. as a polyoxyethylene alkylphenyl ether phosphate ester (mixture of monoester and diester), polyoxyethylene alkyl ether phosphate ester (monoester) "Phosphanol ML-220" manufactured by the same company as a mixture of the same and diester) "Phosphanol RA-600" manufactured by the same company as polyoxyethylene alkyl ether phosphate ester (a mixture of monoester and diester), polyoxy In addition to “Phosphanol RE-610” manufactured by the same company as an ethylene alkylphenyl ether phosphate (mixture of monoester and diester), polyoxyethylene alkylphenyl ether phosphate (monoester and diester) As ester mixture) manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. of "PLYSURF A212E", "Plysurf A212C", it can be exemplified such as "Plysurf A208B".

An organic amine can also be added to the color changing liquid. By adding an organic amine, it is possible to reliably suppress the occurrence of a residual color when the ink is erased.
Examples of the organic amine include n-amylamine, 2-ethylbutylamine, ethylenediamine, diethylenetriamine, aniline, n-butylamine, diamylamine, diethanolamine, n-tributylamine, triamylamine, and triethanolamine.

  In addition, rust preventives, antiseptics or antifungal agents such as carboxylic acid, wetting agents, antifoaming agents such as methylpolysiloxane, polyalkylene glycol fatty acid esters, ethylene, etc., as long as they do not affect the decoloring performance as required A lubricant such as an oxide addition type cationic activator may be used.

In addition, a polysaccharide or a water-soluble resin can be added to impart shear thinning viscosity to the color changing liquid.
Examples of the polysaccharide include welan gum, tamarind gum, guar gum, alka gum, xanthan gum, and succinoglycan (average molecular weight of about 1 to 8 million) in which the constituent monosaccharide is an organic acid-modified heteropolysaccharide of glucose and galactose. Alternatively, they can be mixed and used.
Furthermore, a water-soluble resin can be used, and examples thereof include alkyd resins, acrylic resins, styrene maleic acid copolymers, polyvinyl pyrrolidone, polyvinyl alcohol, and dextrin.

The discoloration liquid having shear thinning viscosity has a viscosity measured at 100 rpm (20 ° C.) of an EM type rotational viscometer in the range of 3 to 160 mPa · s, and a shear thinning index [shear stress value (T ) And the shear rate (j) value derived from rheological measurements (T = Kj ^n, where n value calculated by applying K and n are calculated constants) is 0 A range of 0.1 to 0.6, preferably 0.1 to 0.5, and more preferably 0.1 to 0.4 is suitable.

The ballpoint pen tip that constitutes the ballpoint pen has a conventional general-purpose tip mechanism, for example, a tip that is formed by cutting a metal to form a ball receiving seat and an ink lead-out portion, and a plurality of inner sides on the inner surface near the tip of a metal pipe. Protrusions are provided by pressing deformation from the outer surface, and between the inward projections, a chip formed with an ink outflow gap extending radially outward from the central part in the radial direction, a metal or plastic chip is made of resin A chip provided with a ball seat or the like can be applied. Particularly, a chip formed by pressing deformation has a relatively small contact area with the rear end of the ball, and can provide a smooth writing feeling with a low writing pressure.
The ball held by the ballpoint pen tip is 0.1 to 3.0 mm, preferably 0.1 to 1.5 mm, more preferably 0.1 to 1.5 mm in outer diameter, such as cemented carbide, stainless steel, ruby, and ceramic. A 1.0 mm ball is effective.
The ballpoint pen tip is provided with a resilient member for projecting the rear end of the ball forward in the tip, and when not writing, the ball is pressed against the inner edge of the tip of the tip to bring it into close contact, and when writing, it is The ball can be retracted to allow ink to flow out, and ink leakage when not in use can be suppressed.
Examples of the elastic member include a metal thin wire spring, a member provided with a straight portion (rod portion) at one end of the spring, a linear plastic processed body, and the like, and can be pressed by an elastic force of 10 to 45 g. Applied.

The accommodating tube connected directly to the ballpoint pen tip or via a connecting member is a general-purpose cylindrical molded member, for example, a molded member made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, etc. It is preferably used in terms of low evaporation and productivity.
Moreover, what has an internal diameter of about 1.5-10 mm is used suitably for the said storage pipe.
Furthermore, by using a transparent, colored transparent, or translucent molded body as the storage tube, the color, remaining amount, etc. of the stored color changing liquid can be confirmed.
The housing tube may be housed in the shaft tube in the form of a refill, or the shaft tube itself having a tip attached to the tip may be used as the housing tube, and the shaft tube may be directly filled with the color changing liquid.
The ballpoint pen of the type that accommodates the refill in the shaft cylinder is a knock type such as a rear end knock or a side knock or a rotary type that allows the refill that does not require a cap to appear and disappear, in addition to a ballpoint pen that is configured to mount a cap. It may be a ballpoint pen.

A liquid stopper (liquid backflow prevention body) is filled at the rear end of the color changing liquid stored in the storage tube.
The liquid stopper is made of a non-volatile liquid and / or a hardly volatile liquid (base oil).
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, poly Ether-modified silicone oil, fatty acid-modified silicone oil and the like can be mentioned, and one kind or two or more kinds 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.
Polybutene or silicone oil is preferably used as the base oil of the liquid stopper, and fatty acid amide or silica is preferably used as the thickener.
The liquid stopper can be used in combination with a resin solid stopper.

  In part (rear end) of the color-changing ballpoint pen, there is a writing instrument or applicator containing a built-in ink containing a dye that is decolored or discolored by a reducing action, or an ink containing a colorant that is not decolored or discolored by a reducing action Provided (so-called double-headed applicator structure), making it possible to discolor or erase the handwriting made of the ink with a single writing instrument, or to re-write on the writing surface of the discolored liquid, thereby providing a writing instrument with excellent portability. be able to.

The color changing ballpoint pen is a writing instrument (color-changing or non-color-changing writing instrument) or coating containing an ink containing a dye that is decolored or discolored by a reducing action, or an ink containing a colorant that is not decolored or discolored by a reducing action. A writing instrument set may be combined with a tool (a discoloring or non-discoloring applicator).
The writing instrument set may be composed of a single color-changing or non-color-changing writing tool and a color-changing ballpoint pen, but a plurality of color-changing or non-color-changing writing tools having different tones, or a plurality of color-changes having different handwriting widths. By making a writing instrument set that combines a color or non-color-changing writing instrument and a ballpoint pen for color change, it is possible to form a variety of handwriting and patterns, and the handwriting and patterns can be discolored or decolored and decolorized. A writing tool set that is remarkably rich and can be rewritten on the writing surface.

In addition, the discoloration property is achieved by using a pen tip that can be formed thicker than the handwriting width formed by the color-changing writing instrument (applicator), in which the handwriting width of the color-changing ballpoint pen used in the double-headed writing instrument or writing instrument set is It becomes possible to discolor or erase the handwriting efficiently.
By applying the pen tip such that the handwriting width of the color-changing ballpoint pen can be formed narrower than the handwriting width formed by the color-changing writing tool (applicator), By overcoating the color-changing ink on the portion where the coating is applied, it is possible to easily form a letter.

  What is a writing instrument (applicator) containing an ink containing a dye that is decolored or discolored by a reducing action used in the double-headed writing instrument or writing instrument set, or an ink containing a colorant that is not decolored or discolored by a reducing action A fiber bundle in which a fiber tip, felt tip, plastic tip, ball tip, fountain pen tip, brush tip, etc. are attached to the writing tip and housed in the shaft tube. The ink occlusion body is made to be impregnated with ink, and the ink is supplied to the tip of the writing. The ink is stored directly inside the shaft tube, and is made of a comb groove-shaped coating liquid storage member (pen core) or fiber bundle. A structure that supplies a predetermined amount of ink to the writing tip by interposing a liquid storage member, a structure that stores ink directly in the shaft cylinder, and supplies a predetermined amount of ink to the writing tip by a valve mechanism The ink was filled into a pen tip and an ink containing tube which communicates with the (barrel), the structure were provided with the liquid stopper and solid plugs for backflow prevention to the rear end of said ink can be exemplified.

As the dye contained in the ink, general-purpose dyes are used as long as they are discolored or decolored by a reducing agent, such as methine dyes, trimethylmethane dyes, diphenylmethane dyes, triphenylmethane dyes, xanthene dyes. Dyes, cyanine dyes, azo dyes, anthraquinone dyes, cyanine dyes, and the like can be used.
Specific examples of the dye include C.I. I. Basic Blue 1, C.I. I. Basic Blue 3, C.I. I. Basic Blue 7, C.I. I. Basic Blue 54, C.I. I. Basic Blue 65, C.I. I. Basic Blue 69, C.I. I. Basic Orange 21, C.I. I. Basic Orange 46, C.I. I. Basic Red 13, C.I. I. Basic Red 14, C.I. I. Basic Red 37, C.I. I. Basic Red 49, C.I. I. Basic Green 1, C.I. I. Basic Green 4, C.I. I. Basic Violet 1, C.I. I. Basic Violet 10, C.I. I. Basic Violet 15, C.I. I. Basic Violet 27, C.I. I. Basic Yellow 49, C.I. I. Acid Blue 93, C.I. I. Acid Red 92, C.I. I. Acid Green 3, C.I. I. Acid Violet 19, C.I. I. Acid yellow 23 etc. can be illustrated.
In addition, by using together with a dye that is discolored or decolored by the reducing agent, and a dye or pigment that is difficult to be discolored by the reducing agent, a handwriting in which the color tone of the dye is mixed is visually recognized at the time of writing, and the color changing liquid is applied to the handwriting. By adhering, one of the dyes can be discolored or decolored so that a handwriting with a different color tone can be visually recognized.
Moreover, it can also be set as the ink which can be rewritten on the surface which apply | coated the color-change liquid by containing only the colorant which does not decolor or discolor by a reducing action in ink.

  As the solvent contained in the ink, a conventional water-soluble organic solvent can be added in addition to water. 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-pyro Don and the like.

In addition, in order to make the coloring property of a dye favorable in ink, it is necessary to make pH of ink 1-6.
Therefore, when the pH of the ink needs to be adjusted in the acidic region, an acidic substance can be added, formic acid, acetic acid, propionic acid, lactic acid, oxalic acid, succinic acid, malic acid, citric acid, tartaric acid, phosphoric acid. In addition, sulfonic acid such as paratoluenesulfonic acid, hydrochloric acid, sulfuric acid, nitric acid and the like are applied. In particular, an organic acid is preferably used because it has a small influence on the color tone of the ink and, when a ball-point pen tip is used, tip wear hardly occurs.
Further, as required, organic amines such as sodium hydroxide, potassium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, triethanolamine, 2-amino-2-propanol, aqueous ammonia, etc. A basic substance can also be used in combination.

A thickener can be added to the ink as necessary in order to impart shear thinning or to impart a desired ink viscosity. For example, water-soluble or dispersible 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 its Derivatives, hydroxyethylcellulose, alginic acid alkyl esters, polymers having a molecular weight of 100,000 to 150,000, mainly composed of alkyl esters of methacrylic acid, thickening with gelation ability extracted from seaweeds such as glucomannan, agar and carrageenan Polysaccharides, benzylidene sorbitol and benzylidene xylitol or their derivatives, inorganic fine particles, polyglycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polyoxyethylene alkyl ether・ Nonionic surfactants having an HLB value of 8 to 12, such as polyoxypropylene alkyl ether, polyoxyethylene alkylphenyl ether, fatty acid amide, salts of dialkyl or dialkenylsulfosuccinic acid, N-alkyl-2-pyrrolidone and anionic A mixture of surfactants, a mixture of polyvinyl alcohol and an acrylic resin, and the like can be used, and these can be used alone or in combination.
Furthermore, water-soluble resins can also be used, and examples thereof include alkyd resins, acrylic resins, styrene maleic acid copolymers, cellulose derivatives, polyvinyl pyrrolidone, polyvinyl alcohol, and dextrin.

Among the thickeners, polyvinyl pyrrolidone and polyvinyl alcohol are preferably used because they function stably even when the ink is in an acidic region and exhibit a desired ink viscosity.
In particular, in a system in which a dye having an ink pH of 1 to 6 exhibits a good color development state, the polyvinyl pyrrolidone and polyvinyl alcohol are excessive even in the initial stage and after the lapse of time, although other thickeners hardly exhibit sufficient functions. Thus, the desired ink viscosity can be maintained without causing an increase in viscosity or a decrease in viscosity.

  In addition, as long as it does not affect the color development and decoloration of the dye, if necessary, anticorrosive agent, antiseptic agent such as coal acid or antifungal agent, surfactant, wetting agent, antifoaming agent such as methylpolysiloxane, lubrication You may use additives, such as an agent.

  Furthermore, when ink is directly stored in the ink storage tube (shaft tube), an ink backflow prevention body (liquid stopper) can be filled at the rear end of the ink. The ink backflow preventer may be used in combination with a resin solid stopper.

  Examples and Comparative Examples are shown in the following table, but the present invention is not limited to the following Examples. In addition, the part in an Example shows a weight part.

The raw materials in the table will be described along the note numbers.
(1) Product name: FISCO BLACK 886, manufactured by Orient Chemical Industry Co., Ltd.
(2) Product name: Phosphanol RM410, manufactured by Toho Chemical Industry Co., Ltd.
(3) Daiichi Kogyo Seiyaku Co., Ltd., trade name: Prisurf A208B
(4) Welan gum, manufactured by Sanki Co., Ltd., trade name: AGWRET-W
(5) Xanthan gum, manufactured by Sanki Co., Ltd., trade name: XANTAN G

Preparation of discoloration liquid The ingredients other than the shear thinning agent were added to water, mixed and stirred, and then the shear thinning agent was added, and the mixture was prepared by stirring at 25 ° C with a disper at 400 rpm for 1 hour. .

Preparation of backflow prevention body (liquid stopper) After adding 15 parts of fatty acid amide as a thickener to 85 parts of polybutene as a base oil, a backflow prevention body was obtained by kneading with 3 rolls.

Production of Ballpoint Pen for Color Change A stainless steel tip provided with a resilient member for holding 1 g of the color change solution of Examples 1 to 5 and holding a ball made of cemented carbide having a diameter of 0.7 mm forwardly biasing the ball. A ballpoint pen refill fitted at one end of a polypropylene pipe (inner diameter 3.8 mm) is filled, and after the backflow prevention body is disposed at the rear end, the ballpoint pen refill is incorporated into a shaft tube to produce a ballpoint pen for discoloration. did.
The discoloration ballpoint pen is provided with a detachable cap.

Preparation of color-changing ink A for writing instruments Blue dye 4.0 parts [manufactured by Clariant GmbH, C.I. I. Acid Blue 93)
Phosphate ester surfactant (lubricant) 0.5 part [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Prisurf 212E]
Coal acid (preservative) 0.1 part Citric acid (pH adjuster) 0.5 part Xanthan gum (thickener) 0.45 part Glycerin 15.0 parts Water 79.45 parts

  A mixture of a part of the solvent with a dye and various additives and a part of the solvent with a thickener added thereto are mixed together, and then stirred for 1 hour to reduce shear viscosity. Ink A was obtained. The pH of the ink was 3.0.

Production of a color-changing ball-point pen (color-changing writing instrument A) A ball-point pen tip having a resilient member that rotatably holds a 0.5 mm ball at the tip and urges the ball forward is connected to the tip via a connecting member. After filling the discolorable ink inside the polypropylene ink containing tube fixed to the opening, add 85 parts of polybutene as a base oil to the rear end of the ink, 15 parts of fatty acid amide as a thickener, An ink backflow preventive body obtained by kneading with three rolls was placed to obtain a color-changing ballpoint pen refill.
Further, the color-changing ballpoint pen refill was incorporated into a shaft tube, and a cap was fitted to produce a color-changing ballpoint pen.
When writing on paper using the color-changing ballpoint pen, a dark blue handwriting was obtained with a light writing feeling.

Preparation of color-changing ink B for writing instruments Red dye 2.0 parts [Hodogaya Chemical Co., Ltd., C.I. I. Basic Red 14]
Phosphate ester surfactant (lubricant) 0.5 part [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Prisurf A212E]
Carboxylic acid 0.1 part Glycerin 15.0 parts Water 82.4 parts

  After adding a dye and various additives into the solvent, the mixture was stirred for 1 hour to obtain a color-changing ink B. The pH of the ink was 3.5.

Production of a color-changing marking pen (color-changing writing instrument B) The color-changing ink B is directly accommodated in a polypropylene shaft tube, and a chisel-type fiber marking is provided at the tip of the shaft tube through a comb groove-shaped ink flow rate adjusting member. A discolorable marking pen was prepared by attaching a pen tip.
When writing on the paper surface using the discolorable marking pen, a dark red handwriting was obtained with a light writing feeling.

Preparation of double-headed writing instrument A Double-headed discoloration by fitting the color-changing ballpoint pen refill of Example 1 into one of the shaft cylinders and fitting the color-changing ballpoint pen refill containing the previously prepared color-changing ink A into the other. I got a writing instrument.
When writing on the paper surface using the color-changing ball-point pen part of the writing instrument, a blue handwriting is obtained, and a color-changing liquid is applied using the color-changing ball-point pen part (Example 1 side) provided on the other side from the handwriting. The blue handwriting disappeared.
Since the double-headed writing instrument can perform writing and erasing with one writing instrument, it is excellent in portability and convenience.

Preparation of double-headed writing instrument B Double-headed by fitting the color-changing ballpoint pen refill obtained in Example 1 above into one of the shaft cylinders and fitting the color-changing marking pen containing the previously prepared color-changing ink B into the other. A discoloring writing instrument B was obtained.
When writing on the paper surface using the color-changing marking pen part of the applicator, a red handwriting is obtained, and further, a color-changing liquid using the color-changing ball-point pen part (Example 1 side) provided on the other side from the handwriting. When applied, the coated area was decolored.
Since the double-headed writing instrument can perform writing and erasing with one applicator, it is excellent in portability and convenience.

Preparation of writing instrument set Along with each of the color changing ball pens obtained in Examples 1 to 5, the color changing ball pen (color changing writing tool A) containing the previously prepared color changing ink A and the color changing property containing the color changing ink B Five types of writing instrument sets were obtained by combining with a marking pen (color-changing writing instrument B).
The five types of writing instrument set, when writing on the paper surface using a writing instrument containing each color-changing ink, blue and red handwriting is obtained, and when applying a color-changing liquid using each color-changing ballpoint pen from the handwriting Each handwriting was decolored or discolored.

  The following tests were conducted using the five types of writing instrument sets.

Color change test After writing a straight line on the report paper using the color change writing tools A and B, the color change when the blue and red handwriting was traced with a color change ballpoint pen was confirmed.

Writability test We observed the handwriting of five consecutive circles on the report paper.
The results of each test are shown in the following table.

The evaluation of the test results is as follows.
Discoloration test ○: Good erasure or discoloration can be achieved with two or fewer strokes.
Writability test ○: Good handwriting was obtained from writing.
Δ: Slight jumping was confirmed in the initial stage, but good handwriting was recovered within three.

Claims (6)

  Discoloration containing at least water and a reducing agent that discolors or discolors an image formed with an ink containing a dye that discolors or discolors by a reducing action in a storage tube to which a ballpoint pen tip is attached directly or via a relay member. A ballpoint pen for color change comprising a liquid and a liquid stopper disposed in contact with the color change liquid at a rear side thereof.   2. The ballpoint pen for color change according to claim 1, wherein the total amount of the color change liquid contains 3 to 30% by weight of a reducing agent.   The color-changing ballpoint pen according to claim 1 or 2, wherein the color-changing liquid contains a phosphate ester-based surfactant.   The color-changing ballpoint pen according to any one of claims 1 to 3, wherein the color-changing liquid contains a colorant that is not decolored or discolored by a reducing action.   5. A writing instrument incorporating an ink containing a dye that is decolored or discolored by a reducing action or an ink containing a colorant that is not decolored or discolored by a reducing action at the rear end of the ballpoint pen for discoloration according to any one of claims 1 to 4. A ballpoint pen for discoloration characterized by a double-headed shape.   5. A writing instrument set comprising the discoloration ballpoint pen according to claim 1 and an ink containing a dye that is decolored or discolored by a reducing action, or a writing instrument that contains an ink containing a colorant that is not decolored or discolored by a reducing action. .