JP5592618B2 - Water-based ballpoint pen - Google Patents

Description

  The present invention relates to an aqueous ballpoint pen ink composition, and more particularly, to an aqueous ballpoint pen ink composition having good writing quality and excellent stability over time by suppressing precipitates in the ballpoint pen tip. .

  Conventionally, a ballpoint pen provided with a ballpoint pen tip using a tip body made of a stainless steel material is well known. In the case of a water-based ballpoint pen using a chip body made of such a stainless steel material, precipitates such as metal salts generated by reaction of manganese ions and chromium ions such as manganese and chromium contained in the stainless steel material in the ink composition In order to prevent this, it has been proposed that the ink composition contains a rust inhibitor such as benzotriazole, a metal sequestering agent, and the like.

  Examples of such water-based ball-point pen ink compositions include Japanese Patent Publication No. 49-45333 “Water-based ink for writing” and Japanese Patent Application Laid-Open No. 8-41409 “Water-based ball-point pen ink composition”. A composition is disclosed.

  Incidentally, an aqueous ballpoint pen ink composition containing a phosphate ester surfactant as a lubricant is disclosed in JP-A-6-57194, "Aqueous ballpoint pen ink to be supplied directly to a pen body" in order to improve the writing quality. JP-A-10-330678 “Titanium oxide-containing water-based ink for ballpoint pens” discloses a water-based ink containing a phosphate ester surfactant.

"Japanese Patent Publication No.49-45333" "JP-A-8-41409" “Japanese Patent Publication No. 6-6589” "Japanese Patent Laid-Open No. 10-330678"

  However, Patent Documents 1 and 2 propose water-based ballpoint pen inks containing rust preventives such as benzotriazole and benzothiadiazole compounds, but the problem is that the lubricity is poor, the writing quality is poor, and blurring is also generated. Was holding.

  Further, as in Patent Document 3, in order to improve the writing quality, when a fatty acid or a salt thereof such as an alkali salt of an unsaturated fatty acid is contained as a lubricant, a metal such as a manganese ion or a chromium ion in the chip body There was a possibility that metal salts would be generated by reaction with ions.

  In addition, as in Patent Document 4, it is possible to improve the lubricity and improve the writing quality by using a phosphoric acid-based lubricant, but in recent years, products with a wide range of multicolors and viscosities have been put on the market. Since the coloring agents, resins, and the like used therewith are also diversified, there is a strong demand for a substance having a lubrication improving property equal to or higher than that of a phosphoric acid based lubricant.

  An object of the present invention is to provide an ink composition for a water-based ballpoint pen that has good writing quality and is excellent in stability over time by suppressing deposits due to metal salts in the chip body.

In order to solve the above problems, the present invention
“1. Provided with a ballpoint pen tip that rotatably holds a ball in a ball holding chamber of a chip body made of stainless steel material at the tip of the ink storage cylinder, and at least water and a colorant are contained in the ink storage cylinder An aqueous ballpoint pen filled with an aqueous ballpoint pen ink composition containing a boron-based extreme pressure agent and an aminocarboxylic acid , wherein the aminocarboxylic acid is carboxymethylpolyethyleneimine, L-aspartic acid (ASDA), L-glutamic acid diacetate (GLDA), cyclohexane diamine tetraacetic acid (CyDTA), or selected one or more of the salts thereof, and an aqueous ballpoint pen, wherein the ball is a cemented carbide ball.
2. 2. A water-based ballpoint pen as set forth in claim 1, wherein a coil spring for pressing a ball made of stainless steel is disposed in the tip body .
3. 3. The aqueous ballpoint pen according to item 1 or 2, wherein the aminocarboxylic acid is carboxymethylpolyethyleneimine .
4). The aqueous content of the aminocarboxylic acid relative to the total weight ink composition described in any of paragraphs 1 through the third term, characterized in that 0.1 to 5.0 wt% Ballpoint pen .
5. The aqueous ball point ink composition, aqueous ballpoint pen as described in any of paragraphs 1 to 4, wherein characterized in that it contains an acrylic resin. Is.

  The present invention uses a water-based ballpoint pen ink composition containing an extreme pressure agent selected from a sulfur-based extreme pressure agent, a boron-based extreme pressure agent, and a chlorine-based extreme pressure agent, and an aminocarboxylic acid. It was possible to provide an aqueous ballpoint pen ink composition having excellent stability over time by suppressing deposits due to metal salts in the chip body.

  A feature of the present invention is that, in an aqueous ballpoint pen ink composition, an extreme pressure agent selected from a sulfur-based extreme pressure agent, a boron-based extreme pressure agent, and a chlorine-based extreme pressure agent is used in combination with an aminocarboxylic acid. is there.

Extreme pressure agents, compounds with a long hydrocarbon chain and ends strongly polar group in the molecule (-SO 3 _H group), physically adsorbed or chemisorbed With increasing temperature metal surfaces in frictional heat, solid It is a substance that has the effect of forming a soft film and improving the lubricity, and can improve the lubricity with the chip body under high writing pressure, obtain a smooth writing feeling, and improve the writing quality. Among these extreme pressure agents, as a result of intensive studies by the present inventors, sulfur-based extreme pressure agents, boron-based extreme pressure agents, and chlorine-based extreme pressure agents have extremely high lubricity and remarkably improve the writing quality. I understood that. Of these, it is preferable to use an extreme pressure agent of a boron compound in consideration of the lubricating effect and stability over time.

  In addition, as described in Patent Document 4, there is already a phosphoric acid extreme pressure agent, which has improved lubricity and improved writing quality. As a result of intensive studies, the use of one or more of sulfur-based extreme pressure agent, boron-based extreme pressure agent, and chlorine-based extreme pressure agent allows the hydrocarbon chain and polar group compound of each extreme pressure agent to be in the ball or chip body. It was found that by adsorbing to the metal surface and forming a lubricating film, the lubricity is improved and the writing quality is improved. Among these, it is more preferable to use an extreme pressure agent of a boron compound in view of the lubrication effect and the stability over time.

  Specifically, sulfur-based extreme pressure agents include sulfurized fats and oils, sulfurized olefins, thiadiazole, polysulfide, zinc dithiocarbamate, sulfurized fatty acid esters, dibenzyl polysulfide, thiophosphate esters, etc., and boron-based extreme pressure agents include polyoxyethylene Examples of chlorinated extreme pressure agents such as diglycerin borate ester and diglycerin borate ester include chlorinated paraffin, chlorinated fatty acid ester, and chlorinated oil. You may use these individually or in mixture of 2 or more types.

  Specifically, ANGLAMOL 81 (manufactured by Nippon Lubrizol Co., Ltd.), SULFURIZED LARD (manufactured by Dainippon Ink Co., Ltd.), Die-Lube S940 (manufactured by Dainippon Ink), ANGLAMOL33 (manufactured by Lubrizol Co., Ltd.), Emulbon T-20, -40, and the like -60, the same -66, the same -80, the same -160, Emalbon S-20, the same -40, the same -60, the same -66, the same -80, the same -83, the same -160 (manufactured by Toho Chemical Industry Co., Ltd.) , Empara K-40, -K45, -K50, and -AR500 (manufactured by Ajinomoto Fine Techno Co., Ltd.).

  If the content of the extreme pressure agent is less than 0.1% by mass with respect to the total amount of the ink composition, the desired lubricity cannot be obtained, the writing quality is poor, and there is a risk of blurring in the handwriting. If the amount exceeds 0.0% by mass, the ink aging may become unstable. Therefore, the amount is set to 0.1 to 5.0% by mass with respect to the total amount of the ink composition. Further, in order to further improve the writing feeling and obtain good ink aging, the content of the extreme pressure agent is most preferably 0.5 to 3.0% by mass with respect to the total amount of the ink composition.

  As described above, the extreme pressure agent can improve lubricity and obtain a smooth writing feeling, but may react with metal ions such as manganese ions and chromium ions in the chip body to form a metal salt. . Since these metal salts do not dissolve in the ink composition, there is a problem that they appear as precipitates.

  In order to solve these problems of improving writing quality and suppressing the generation of precipitates due to metal salts, it is important in the present invention to contain an aminocarboxylic acid in the aqueous ballpoint pen ink composition.

  Aminocarboxylic acid is a compound having an amino group and a carboxyl group, but envelops the entire generated metal salt and dissolves and stabilizes the metal salt in the ink composition, thereby suppressing the generation of metal salt precipitates. There is. Therefore, as in the present invention, in order to improve lubricity, when using at least an extreme pressure agent selected from a sulfur extreme pressure agent, a boron extreme pressure agent, and a chlorine extreme pressure agent, an aminocarboxylic acid is used in combination. By doing so, it is possible to obtain an ink composition for water-based ballpoint pens having good writing quality and excellent stability over time by suppressing precipitates due to metal salts in the chip body.

  Specific examples of aminocarboxylic acids include carboxymethylpolyethyleneimine, L-aspartic acid (ASDA), L-glutamic acid diacetic acid (GLDA), cyclohexanediaminetetraacetic acid (CyDTA), hydroxyethylethylenediaminetriacetic acid (HEDTA), and diethylenetriamine. Examples thereof include pentaacetic acid (DTPA), dihydroxyethylglycine (DHEG), hydroxyethyliminodiacetic acid (HIDA), and salts thereof such as alkali metal salts, ammonium salts, and amine salts. You may use these individually or in mixture of 2 or more types.

  Further, among aminocarboxylic acids having a carboxyl group, carboxymethylpolyethyleneimine (Chemical Formula 1), L-aspartic acid (chemical formula 1) represented by chemical formulas such as (Chemical Formula 1) to (Chemical Formula 4) having a strong effect of dissolving a metal salt. ASDA) (Chemical Formula 2), L-glutamic acid diacetic acid (GLDA) (Chemical Formula 3), cyclohexanediaminetetraacetic acid (CyDTA) (Chemical Formula 4), or salts thereof are preferred.

（式中、ｎは整数を、Ｘは水素、アルカリ金属、アンモニウム、アミンの中のいずれかを示す。） Furthermore, carboxymethylpolyethyleneimine (Chemical Formula 1) forms a polymer and has a very high molecular weight. In particular, when the molecular weight is 10,000 or more, the straight chain becomes longer and a larger structure is formed, so that the effect of suppressing the reaction between the metal ion and the fatty acid due to steric hindrance becomes stronger. Moreover, since it is excellent in biodegradability and can reduce environmental impact, it can cope with recent remarkable environmental problems. Therefore, among aminocarboxylic acids, it is most preferable to use carboxymethylpolyethyleneimine.

(In the formula, n represents an integer, and X represents hydrogen, alkali metal, ammonium, or amine.)

Specific examples of these aminocarboxylic acids include L-aspartic acid-N-N-diacetic acid tetrasodium salt (ASDA-4Na), Clewat Bi-ADS (Nagase Chemtech Co., Ltd.), L-glutamic acid di-acid. As acetic acid tetrasodium salt (GLDA-4Na), Cyrest CMG-40 (Chubu Kirest Co., Ltd.) cyclohexanediamine tetraacetic acid / H ₂ O (CyDTA) as CyDTA (Dojin Chemical Laboratories) Hydroxyethylethylenediamine Examples of trisodium triacetate (HEDTA-3N a · H ₂ O) include Clewat OH300 (Nagase Chemtech Co., Ltd.).

  On the other hand, if the content of aminocarboxylic acid is less than 0.1% by mass relative to the total amount of the ink composition, the effect of suppressing precipitation of metal salts may be weakened, and if it exceeds 5.0% by mass. In addition, since the ink aging becomes unstable, it is set to 0.1 to 5.0% by mass with respect to the total amount of the ink composition. More preferably, 0.5-3.0 mass% is suitable with respect to the ink composition whole quantity.

  The colorant is not particularly limited, and may be appropriately selected and used. As the dye, direct dyes, acid dyes, basic dyes, metal-containing dyes, various water-soluble salt-forming dyes, and the like can be used. Examples of pigments include inorganic, organic, and processed pigments. Specifically, carbon black, aniline black, ultramarine, yellow lead, titanium oxide, iron oxide, phthalocyanine, azo, quinacridone, quinophthalone, selenium , Triphenylmethane, perinone, perylene, glyoxazine, aluminum pigment, pearl pigment, fluorescent pigment, phosphorescent pigment, and complementary color pigment. Alternatively, a microcapsule pigment obtained by encapsulating or solidifying a colored body in which a pigment is dispersed in a medium as a colored resin particle body in a shell made of a resin wall film-forming substance by a known microencapsulation method may be used. good. Further, colored resin particles in which the pigment is covered with a transparent or translucent resin or the like, or colored resin particles or colorless resin particles colored with a pigment or a dye can also be used. These dyes and pigments may be used alone or in combination of two or more. The content is preferably 1% by mass to 20% by mass with respect to the total amount of the ink composition.

  In the present invention, a resin may be used as an ink viscosity modifier or a pigment dispersant, and water-soluble resins such as acrylic resins, alkyd resins, cellulose derivatives, polyvinyl pyrrolidone, and polyvinyl alcohol, xanthan gum, and cross-linked acrylic acid. Examples include shear thinning agents such as polymers, succinoglycans and gar gums. Among them, when an acrylic resin is added, a large number of carboxyl groups are present, and the effect of suppressing metal salt precipitates is also exerted, which also plays a role like aminocarboxylic acid. Therefore, in the present invention, it is preferable to use an acrylic resin such as a cross-linked acrylic acid polymer or an acrylic resin having two effects as an ink viscosity modifier and an aminocarboxylic acid. You may use these individually or in mixture of 2 or more types. You may use these individually or in mixture of 2 or more types.

 Moreover, if the addition amount of the resin is less than 0.1% by mass relative to the total amount of the ink composition, it is difficult to obtain a desired ink viscosity, and if it exceeds 30% by mass, the writing performance may be deteriorated. Therefore, 0.1 mass%-30 mass% is preferable.

  In addition, in consideration of water dissolution stability, moisture evaporation drying prevention, etc., water-soluble organic solvents such as glycerin and ethylene glycol, considering improvement in lubricity, phosphate ester-based, silicon-based surfactants, A pH adjuster such as triethanolamine, a humectant such as urea or sorbit, a rust inhibitor such as benzotriazole, and a fungicide such as 1,2 benzoisothiazolin-3-one can be added. Also, a fixing agent can be added as appropriate, and an acrylic resin, urethane resin, styrene-butadiene resin, polyester resin, vinyl acetate resin, or the like can be added as a resin emulsion. These can be used alone or in combination of two or more.

  Further, the ball-point pen tip ball is not particularly limited, but a cemented carbide ball mainly composed of tungsten carbide uses cobalt, nickel, or the like as its binder. The carboxymethylpolyethyleneimine, L-aspartic acid (ASDA), L-glutamic acid diacetic acid (GLDA), cyclohexanediaminetetraacetic acid (CyDTA), or a salt thereof with respect to metals such as cobalt and nickel over time. Since it is difficult to corrode, it does not cause ball rotation resistance due to corrosion, a good writing quality is obtained, and it can be suitably used for cemented carbide balls.

Next, an Example is shown and this invention is demonstrated.
Example 1
Water 27.6 parts by mass Water-soluble organic solvent (glycerin) 20.0 parts by mass Aminocarboxylic acid (L-aspartic acid-N-N-diacetic acid tetrasodium salt) 0.5 parts by mass Boron extreme pressure agent (Emalbon T -20) 1.0 part by mass urea 7.5 parts by mass pH adjuster (triethanolamine) 3.0 parts by mass antibacterial agent (1,2 benzoisothiazolin-3-one) 0.2 parts by mass rust inhibitor (Benzotriazole) 0.2 parts by mass Colorant (NKW-2100 series) 40.0 parts by mass Resin (succinoglycan) 0.20 parts by mass

  In Example 1, first, water, a water-soluble organic solvent, a boron-based extreme pressure agent (Emalbon S-20), L-aspartic acid-N-N-diacetic acid tetrasodium salt (Clewat Bi-ADS (Nagase Chemtech Co., Ltd.) )), PH adjuster, moisturizer, antibacterial agent, rust preventive agent, and colorant are heated and stirred with a magnetic hot stirrer to prepare a base ink.

  Thereafter, while heating the base ink produced, the resin was added and sufficiently mixed and stirred using a homogenizer stirrer until a uniform state was obtained. Then, it filtered using the filter paper and obtained the ink composition for water-based ball-point pens of Example 1.

Examples 2-6
A water-based ballpoint pen ink composition was prepared in the same procedure as in Example 1 except that each component was changed to the formulation shown in Table 1.

Comparative Examples 1-4
A water-based ballpoint pen ink composition was prepared in the same procedure as in Example 1 except that each component was changed to the formulation shown in Table 2.

Test and evaluation The tip of the ink containing cylinder is equipped with a ballpoint pen tip that rotatably holds a cemented carbide ball having a ball diameter of φ0.7 mm in a ball holding chamber of a chip body made of stainless steel material, and ink A refill in which the water-based ink composition prepared in Examples 1 to 6 and Comparative Examples 1 to 4 and the grease-like ink follower were directly filled in the containing cylinder was used as a gel ink ballpoint pen (trade name: manufactured by Pilot Corporation). G-knock) was mounted on the water-based ballpoint pen of the present invention, and the following tests and evaluations were performed. In addition, using the copy paper (PPC paper) as a writing taste and writing test paper, it evaluated by the following items.

Writing taste: A ballpoint pen refill was evaluated after a handwriting sensory test after standing for 2 weeks in a room temperature environment.
Smooth and good ・ ・ ・ ◎
Somewhat inferior ・ ・ ・ ○
Heavy and inferior ・ ・ ・ ×

Time-lapse test of chip body: The ink in the chip body was observed with a microscope after leaving the ballpoint pen refill in an environment of 50 ° C. and 0% humidity for 3 months.
Good without deposits ... ◎
Slightly generated precipitates, but no problem in practical use
Precipitate is present and causes scumming or poor writing ・ ・ ・ ×

    In Examples 1 to 6, good performance was obtained for both the writing quality and the aging test of the chip body.

  In Comparative Examples 1 and 2, since no aminocarboxylic acid was contained, a precipitate was generated, resulting in poor writing.

  In Comparative Examples 3 and 4, since a sulfur-based extreme pressure agent, a boron-based extreme pressure agent, and a chlorine-based extreme pressure agent were not contained, sufficient lubricity was not obtained and writing was heavy.

  Although not shown, when a coil spring that presses a ball made of stainless steel is provided in the ballpoint pen tip, the reaction between the extreme pressure agent and the metal ion of the coil spring is the same as the tip body. Since there is a possibility that a metal salt is generated due to the above, the effect of the present invention is remarkable.

  Furthermore, in an ink composition containing a pigment having a large particle size such as a pigment, there is a possibility of deterioration in writing quality due to rotation inhibition between the ball and the chip body, and a ball having a ball diameter of 0.7 mm or less was used. Since the ball pen has a small contact area between the ball and the ball seat, and there is a possibility that the writing quality is deteriorated due to a high load applied to the unit area, the effect of the present invention is remarkable.

  The present invention relates to an aqueous ballpoint pen, and more specifically, an aqueous ballpoint ink composition containing at least water, a colorant, an extreme pressure agent, and an aminocarboxylic acid, wherein the extreme pressure agent is a sulfur-based extreme pressure agent, By using an aqueous ballpoint pen ink composition characterized by being selected from at least one of a boron-based extreme pressure agent and a chlorine-based extreme pressure agent, the writing quality is good, and the metal salt in the ballpoint pen tip, etc. By suppressing it, an aqueous ballpoint pen having excellent stability over time can be provided. Therefore, it can be widely used as a ballpoint pen, such as a cap type and a knock type.

Claims (5)

At the tip of the ink storage cylinder, the ball holding chamber of the chip body made of stainless steel material is provided with a ballpoint pen tip that rotatably holds the ball, and at least water, colorant, boron-based in the ink storage cylinder An aqueous ballpoint pen filled with an aqueous ballpoint pen ink composition containing an extreme pressure agent and an aminocarboxylic acid , wherein the aminocarboxylic acid is carboxymethylpolyethyleneimine, L-aspartic acid (ASDA), L-glutamic acid diacetic acid ( GLDA), cyclohexane diamine tetraacetic acid (CyDTA), or selected one or more of the salts thereof, and an aqueous ballpoint pen, wherein the ball is a cemented carbide ball. The water-based ballpoint pen according to claim 1, wherein a coil spring that presses a ball made of stainless steel is disposed in the tip body . The water-based ballpoint pen according to claim 1 or 2, wherein the aminocarboxylic acid is carboxymethylpolyethyleneimine . The water-based ballpoint pen according to any one of claims 1 to 3, wherein the content of the aminocarboxylic acid is 0.1 to 5.0% by mass with respect to the total mass of the ink composition. The aqueous ball point ink composition, aqueous ballpoint pen as claimed in any one of claims 1 to 4, characterized in that it contains an acrylic resin.