JP5770994B2 - Ballpoint pen refill - Google Patents

Description

    The present invention relates to a ballpoint pen refill, and more particularly to a ballpoint pen refill in which a ballpoint pen tip made of a stainless steel material is mounted directly or via a tip holder on an end portion of an ink containing cylinder.

  Conventionally, a ballpoint pen refill in which a ballpoint pen tip made of a stainless steel material is mounted directly or via a tip holder on the tip of an ink containing cylinder is well known and disclosed in Japanese Patent Application Laid-Open No. 2001-301378, “Ballpoint Pen Tip” and the like. Has been. Stainless steel is a material suitably used as a ballpoint pen tip because of its good wear resistance.

  However, even a ballpoint refill using a ballpoint pen tip made of stainless steel has a problem that the tip body such as a ball seat is worn by the rotation of the ball by writing. When the ball seat is worn, the amount of movement of the ball in the tip in the axial direction, so-called clearance, increases.

  As described above, when the wear of the chip body progresses due to the rotation of the ball by writing and the clearance becomes large, various problems such as ink drooping and the inside of the chip being easily dried cause deterioration of the writing performance.

  In order to suppress such abrasion, as disclosed in JP-A-6-248217, “Ink Composition for Ballpoint Pen”, JP-A-9-151354, “Ink Composition for Oil-Based Ballpoint Pen”, etc. The use of various surfactants such as fluorine-based surfactants and silicon-based surfactants for the ballpoint pen ink filled into the ball would increase lubricity and reduce the rotational resistance between the ball and the chip body. It is done.

"JP 2001-301378 A" "Japanese Patent Laid-Open No. 6-248217" "Japanese Patent Laid-Open No. 9-151354"

  However, when various surfactants such as Patent Documents 2 and 3 are used, the writing quality can be improved to some extent, but the effect of suppressing the wear of the ball seat and the tip is not fully satisfactory. It was.

In addition, when an ink having an ink viscosity of 10 to 5000 mPa · s at 20 ° C. and a shear rate of 500 sec ⁻¹ is used, there is a problem that the ink consumption greatly increases due to wear as well as the above-described sag. is there. When the ink consumption increases, new problems such as the scratch resistance of the handwriting deteriorating and soiling the paper surface occur.

  The object of the present invention is to provide a ballpoint pen refill that has good writing quality, maintains lubricity, is hard to wear on the chip body such as a ball seat, and has stable ink consumption from the start of writing to the end of ink. It is to be.

In order to solve the above problems, the present invention
“1. A ballpoint pen tip made of stainless steel with a ball rotatably held at the tip of the ink containing cylinder is mounted directly or via a chip holder, and the ink containing cylinder has at least an aromatic ring inside. containing compounds, 20 ° C., the ink viscosity at a shear rate of 500 sec ^-1, directly oily ball point ink is 10~5000mPa · s, a housing and comprising ballpoint refill ink consumption 0~100m time A ballpoint pen refill satisfying 1.20 ≧ Y1 / Y2 ≧ 0.80 when Y1 mg and ink consumption Y2 mg of 100 m before the end of ink are set.
2. 2. The ballpoint pen refill according to item 1, wherein the movement amount of the ball in the axial direction is 3 to 15 μm.
3. 3. The ballpoint pen refill according to item 1 or 2, wherein the acidic compound having an aromatic ring has a molecular weight of 200 or more.
4). Content of the acidic compound which has the said aromatic ring is 0.1-20.0 mass%, The ball-point pen refill of any one of Claim 1 thru | or 3 characterized by the above-mentioned.
5. Item 5. The ballpoint pen refill according to any one of Items 1 to 4, wherein the acidic compound having an aromatic ring is alkylbenzenesulfonic acid.
6). 6. The ballpoint refill according to any one of items 1 to 5, wherein the oil-based ballpoint pen ink has a pH of 4 to 10. Is.

  The present invention provides a ballpoint pen refill that has good writing quality, maintains lubricity, is less likely to wear a chip body such as a ball seat, and has stable ink consumption from the start of writing to the end of ink. I was able to.

It is a longitudinal cross-sectional view of the ball-point pen refill in this invention. FIG. 2 is an enlarged cross-sectional view of a main part, partly omitted in FIG. 1.

  The first feature of the present invention is that, in the ballpoint pen refill comprising a ballpoint pen tip made of stainless steel at the tip of the ink containing cylinder, the oily ballpoint pen ink contains an acidic compound having an aromatic ring. .

  The stainless steel material has better wear resistance than copper alloys such as brass, but it is important to improve the lubricity of the ballpoint pen ink and reduce the wear of the chip body such as the ball seat. Therefore, in the present invention, it is important to contain an acidic compound having an aromatic ring in the oil-based ballpoint pen ink.

  The acidic compound having an aromatic ring used in the present invention is an acidic compound having a benzene ring, a naphthalene ring, an anthracene ring or the like. As a result of diligent research on the lubricity, the present inventor has included an acidic compound having an aromatic ring in the ink composition for oil-based ballpoint pens, so that writing quality is good and wear of the ball seat can be suppressed. I understood that it would be possible. This is because an acidic compound having an aromatic ring forms a lubricating film that is easily adsorbed to the metal, and has the effect of suppressing metal contact between the ball and the chip body, improving lubricity and improving writing quality. In addition, it is assumed that the wear of the ball seat is suppressed. Furthermore, the lubricating film formed by the acidic compound having an aromatic ring is protected by covering the oxide film on the surface of the stainless steel material, and the deterioration of the oxide film is suppressed, so that the corrosion resistance of the ballpoint pen tip and the like is stable over time. It is estimated that the effect of improving the effect can be obtained.

  The second feature of the present invention is that 1.20 ≧ Y1 / Y2 ≧ 0.80 when the ink consumption Y1 mg at the time of 0 to 100 m and the ink consumption Y2 mg at 100 m before the end of the ink are set. .

This is because obtaining a stable writing performance from the start of writing to the end of ink is also an important issue for ballpoint pen refills. Ink viscosity oil ballpoint pen ink used in the present invention, 20 ° C., the ink viscosity at a shear rate of 500 sec ^-1 is 10~5000mPa · s and conventional oil-based ballpoint pen ink, 20 ° C., the ink viscosity at a shear rate of 500 sec ^-1 By making the viscosity lower than about 10,000 to 20,000 mPa · s and containing an acidic compound having an aromatic ring, it further enhances lubricity and improves writing quality. However, due to the low viscosity, when Y1 / Y2> 1.20, the scratch resistance is deteriorated and the total writing distance is shortened, and when Y1 / Y2 <0.80, writing performance such as handwriting density and writing quality is reduced. In order to decrease, when the ink consumption Y1 mg at 0 to 100 m and the ink consumption Y2 mg at 100 m before the end of ink, 1.20 ≧ Y1 / Y2 ≧ 0.80, from the start of writing to the end of ink, It is important to maintain the ink consumption within the above-mentioned range, and it is preferable to satisfy 1.15 ≧ Y1 / Y2 ≧ 0.90 considering the effect of writing performance.

  By the way, if the ink consumption Y1 mg at 0 to 100 m and the ink consumption Y2 mg at 100 m before the end of ink are set to 1.20 ≧ Y1 / Y2 ≧ 0.80, the wear of the chip body is suppressed. Is the most important factor. However, it is not possible to obtain stable writing performance from the start of writing to the end of ink simply by suppressing the wear of the chip body. As described above, the present invention contains an acidic compound having an aromatic ring, thereby improving the lubricity between the ball and the chip body to suppress wear of the chip body and to suppress deterioration of the oxide film. In order to improve the stability over time in the chip body, such as the corrosion resistance of ballpoint pen tips, the ink flow and writing performance can be stabilized by maintaining a smooth ink flow from the beginning of writing to the end of ink. It can be done.

When the ink viscosity of the oil-based ballpoint pen ink of the present invention is less than 10 mPa · s at 20 ° C. and a shear rate of 500 sec ⁻¹ , the handwriting is likely to be affected by bleeding and ink dripping. When the ink viscosity at 5000 ° C. and a shear rate of 500 sec ⁻¹ exceeds 5000 mPa · s, the ball rotation resistance during writing tends to increase, and the writing taste tends to become heavy. Therefore, the ink viscosity at 20 ° C. and a shear rate of 500 sec ⁻¹ is preferably 10 to 5000 mPa · s. More preferably, it is 50-3,000 mPa * s, Most preferably, it is 100-1500 mPa * s.

  Moreover, it is preferable that the movement amount of the ball-point pen tip used in the present invention in the axial direction of the ball is 3 μm to 15 μm. If it is less than 3 μm, the ink consumption tends to be small, which may cause poor handwriting and other handwriting defects. If it exceeds 15 μm, it becomes difficult to stably supply the ink, and 1.20 ≧ Y1 / Y2 ≧ 0. .80 cannot be satisfied.

  The acidic compound having an aromatic ring used in the present invention is an acidic compound having an aromatic ring such as a benzene ring, a naphthalene ring, or an anthracene ring. The acidic compound having an aromatic ring includes a large number of aromatic rings such as a benzene ring. Since it is easier to improve the lubricity, it preferably has a molecular weight of 200 or more.

Specific examples of the acidic compound having an aromatic ring include alkylbenzene sulfonic acid, naphthalene sulfonic acid, naphthalene sulfonic acid-formaldehyde condensate, alkyl diphenyl ether disulfonic acid, polyoxyethylene alkyl phenyl ether phosphoric acid and the like. In consideration of writing, it is preferable to include a sulfur-based compound having a high adsorptivity to a metal surface, alkylbenzenesulfonic acid (RC ₆ H ₄ —SO ₃ ^— , R: alkyl group) is preferable, and dodecylbenzenesulfone. Acid, dodecyl diphenyl oxide sulfonic acid, and the like.

  If the content of the acidic compound having an aromatic ring is less than 0.1% by mass relative to the total amount of the ink composition, the desired lubricity may not be obtained. If it exceeds 20.0% by mass, Is likely to be unstable, so 0.1 to 20.0% by mass is preferable with respect to the total amount of the ink composition. More preferably, it is 0.5-10.0 mass% with respect to the ink composition whole quantity, Most preferably, it is 2.0-8.0 mass%.

Such acidic compounds having an aromatic ring include anionic or cationic surfactants, but some surfactants have water-soluble properties and tend to be difficult to dissolve in oil-based inks. Insufficient ink stability over time remains. Therefore, it is preferable to use a salt-formation product obtained by neutralizing an acidic compound having an aromatic ring with a basic compound. The salt formation obtained in this manner is preferable because it has a strong ionic binding force and remarkably improves long-term ink aging stability. Furthermore, considering lubricity, it is preferable that each of the acidic compound and the basic compound has an aromatic ring, and more preferably, the compound having an aromatic ring is a functional group (S, SO, SO ₂ having a sulfur atom). , SO _3, etc.) is preferable because a strong lubricating layer is formed between the ball and the ball seat, so that the lubricity is considered to be improved.

Further, when an organic amine having ethylene oxide (CH ₂ CH ₂ O) is used in combination with the salt structure, a lubricating effect is more easily obtained. Therefore, it is preferable to use oxyethylene alkylamine or polyoxyethylene alkylamine having ethylene oxide (CH ₂ CH ₂ O) as the organic amine. You may use these individually or in mixture of 2 or more types.

  By the way, the oily ballpoint pen ink contains an acidic compound having an aromatic ring, and in order to maintain the ink stability with time and the corrosion resistance of the chip body, pH 4.0 to 10.0 is preferable, and pH 5.0 to 9.0. Most preferably. When the pH value is 3.9 or less, metal ions in the chip body are likely to elute, so that metal salt precipitates are easily generated. When the pH value is 10.1 or more, good color tone and dispersion of the colorant are obtained. Since stability cannot be obtained, by setting the pH value to an intermediate region of 4.0 to 10.0, the ink aging stability is improved and the influence on the corrosion resistance of the chip body can be reduced.

  Furthermore, in consideration of the stability of the salt-forming body, when the pH value is a strongly acidic region having a pH value of 3.9 or less and the strong alkali region having a pH value of 10.1 or more, the ionic bond of the salt-forming body is easily released. For this reason, an intermediate region (weakly acidic, neutral, weakly alkaline) having a pH of 4.0 to 10.0 is most preferable because the stability over time is good.

  In the method for measuring oil-based ballpoint pen ink, the pH value in the present invention is obtained by collecting oil-based ink in a container, adding ion-exchanged water, heating with stirring, allowing to cool after heating, and evaporating. After replenishing the amount of water, filter using filter paper. The value measured at 20 ° C. with a pH meter using the upper layer of the filtered filtrate is shown.

  As for the colorant used in the present invention, there are dyes and pigments. As for the dyes, there are oil-soluble dyes, acid dyes, basic dyes, metal-containing dyes, direct dyes, and various salt-forming dyes. It can be adopted. Examples of the pigment include inorganic, organic and processed pigments. These dyes and pigments can be used in combination of two or more. In particular, it is preferable to use a dye for the pigment because there is a possibility that the writing quality is deteriorated due to rotation inhibition between the ball and the chip body.

For oil-based dyes, specifically, Bali First Black 1802, Black 1805, Black 1701, Blue 1601, Blue 1621, Red 1320, Red 1360, Yellow 1101, Yellow 1151, Nigrosine Base EXBP, Nigrosine Base EX, BASE OF BASIC DYES ROB-B, RO6G-B, VPB-B, VB-B, MVB-3, Eisenspiron Black GMH-Special, Violet C-RH, Blue GNH, Blue C-RH, Red C-GH, Red C-BH, Yellow C-GNH, Yellow C-2GH, S. P. T.A. Blue 111, Blue GLSH-special, Red 533, Orange 6, S. B. N. Violet 510, S.I. B. N. Yellow 510, Yellow 530, S.I. R. C-BH etc. are mentioned.
Specific examples of water-based dyes include Direct Black 17, 19, 22, 154, 195, Acid Black 1, 2, 24, Direct Yellow 4, 26, Direct Red 1, 23, 31, Direct Blue 1, 41, 71, 119, Direct Orange 6, etc., Acid Black 1, 2, 24, 26, Acid Orange 56, Acid Yellow 3, 17, 42, 61 Acid Red 8, 9, 9, 51, Acid Blue 1, 7, 62, 90, Acid Green 3, 9, 16, Acid Violet 15, 17, C.I. I. Basic erotic-1, 2 and 21, C.I. I. Basic Orange 2, 14 and C.I. I. Basic Red 1, 2 and 9, C.I. I. Basic Violet 1, 3, 10, and C.I. I. Basic Bull-3, 7 and 26, Basic Green 4, C.I. I. Basic Brown 12, C.I. I. Examples include Basic Black 2, Methyl Violet, Victoria Blue FB, Malachite Green, and Rhodamine series.

  Examples of pigments include inorganic, organic, and processed pigments. Specifically, carbon black, aniline black, ultramarine, yellow lead, titanium oxide, iron oxide, phthalocyanine, azo, quinacridone, and quinophthalone Selenium, triphenylmethane, perinone, perylene, goxazine, metallic pigment, pearl pigment, fluorescent pigment, phosphorescent pigment, and the like. These dyes and pigments may be used alone or in combination of two or more. As for content of a coloring agent, 1.0-50.0 mass% is preferable with respect to the ink composition whole quantity.

  Examples of the solvent used in the present invention include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol dimethyl ether, ethylene glycol monophenyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, diethylene glycol dimethyl ether, 3- Glycol ethers such as methoxybutanol and 3-methoxy-3-methylbutanol, glycols such as diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, butylene glycol and ethylene glycol, benzyl alcohol, methanol, ethanol, 1 -Propanol, 2-propano , Isopropanol, isobutanol, t-butanol, propargyl alcohol, allyl alcohol, 3-methyl-1-butyn-3-ol, alcohols such as ethylene glycol monomethyl ether acetate and other higher alcohols, phenyl cellosolve, etc. The solvent generally used as ink for ball-point pens, such as cellosolve, can be illustrated, and these can be used 1 type or 2 or more types. The content of the organic solvent is preferably 5.0 to 50.0% by mass with respect to the total amount of the ink composition in consideration of solubility of the colorant, handwriting drying property, blurring, and the like.

  In addition, in order to improve the aging stability and lubricity of the colorant, as the organic amine and surfactant, phosphate ester surfactant, fluorine surfactant, silicon surfactant, acetylene Surfactant, fatty acid, etc. as pigment dispersant, polyvinyl butyral resin, polyvinyl alcohol resin, acrylic resin, etc., viscosity modifier, ketone resin, terpene resin, alkyd resin, phenoxy resin, polyvinyl acetate, polyvinyl pyrrolidone, etc. Pseudoplasticity imparting agents such as resins, fatty acid amides, hydrogenated castor oil, and cellulose derivatives, and colorant stabilizers, plasticizers, chelating agents, water, rust preventives, antibacterial agents, etc. . These may be used alone or in combination of two or more.

  Next, embodiments of the ballpoint pen of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.

Example 1
The ballpoint pen refill 1 according to the first embodiment shown in FIGS. 1 and 2 is provided with a ballpoint pen tip 4 in which a ball 3 having a ball diameter of φ0.7 mm is rotatably held at the tip of an ink containing cylinder 2 and also contains ink. In the cylinder 2, the ballpoint refill 1 is obtained by directly accommodating the ink 11 for ink-based ballpoint pen 11 (0.4g) and the ink follower 12 in the ink composition 1. Further, in the ball-point pen tip 4, a coil spring 10 that always presses the ball 3 against the inner wall of the tip end edge 5a is disposed at the rear end of the ball.

  The ballpoint pen tip 4 has an ink circulation hole 7 and a radially extending ink circulation groove 8 in the ball holding chamber 6, and a ball seat 9 having substantially the same shape as a writing ball provided on the bottom wall of the ball holding chamber 6. By placing the ball 3 and caulking the tip end edge 5a of the tip end portion 5 inward, a part of the ball 3 is rotatably held so as to protrude from the tip end edge 5a.

Oil-based ballpoint pen inks are colorants, dyes, organic solvents, benzyl alcohol, ethylene glycol monophenyl ether, salt formation of acidic compounds (alkylbenzene sulfonic acids) with aromatic rings and basic compounds (benzoxonium compounds) Body (salt formation formulation 1, molecular weight 600-700), oleic acid as organic acid, polyvinylpyrrolidone (PVP K-90: manufactured by ASP Japan Co., Ltd.) as resin, ketone resin (Hilac 110H: manufactured by Hitachi Chemical Co., Ltd.) ), Weighed a predetermined amount, heated to 60 ° C., and then completely dissolved using a disper stirrer to obtain an oil-based ballpoint pen ink. Specific blending amounts are as follows. The ink viscosity was measured at a shear rate of 500 sec ^-1 in an environment of 20 ° C. using AR-G2 (stainless steel 40 mm 2 ° rotor) manufactured by TA Instruments Inc. s.

Ink formulation 1
Dye (Spiron Black-GMH-S) 15.0% by mass
Dye (Barry First Violet 1701) 15.0% by mass
Solvent (benzyl alcohol) 60.7 mass%
Salted product of an acidic compound having an aromatic ring and a basic compound (produced in Formulation Example 1) 5.0% by mass
Stabilizer (oleic acid) 1.0% by mass
Stabilizer (polyoxyethylene alkylamine) 1.0% by mass
Resin (Polyvinylpyrrolidone) 0.3% by mass
Resin (ketone resin) 2.0% by mass

Salt formation example 1
First, 100 g of water and 30 g of alkylbenzenesulfonic acid Na were weighed in a beaker and heated, and then dissolved using a disper stirrer. Then, 19.5 g of a benzoxonium compound was weighed, stirred, and filtered using a filter paper. To obtain a salt structure.

Formulation Examples 2-5
As shown in Table 1, salt-making bodies of Formulation Examples 2 to 5 were prepared in the same manner as Formulation Example 1, except that each component was changed.

Examples 2 to 3, Reference Examples 1 and 2
As shown in Table 2, oil-based ballpoint pen inks of Examples 2-3 and Reference Examples 1 and 2 were obtained in the same procedure as Example 1 except that each component was changed. Table 2 shows the measurement and evaluation results.

Comparative Examples 1-4
As shown in Table 3, the oil ballpoint pen inks of Comparative Examples 1 to 4 were obtained by blending in the same procedure as in Example 1 except that each component was changed. Table 3 shows the measurement and evaluation results.

Testing and evaluation
The oil ballpoint pen inks prepared in Examples 1 to 3, Reference Examples 1 and 2 and Comparative Examples 1 to 4 were filled in the ballpoint pen refill of Example 1, and the following test was performed using writing paper JIS P3201 as writing test paper. And evaluated.

Written taste: A hand-written sensory test was performed and evaluated.
Smooth and good ・ ・ ・ ◎
Somewhat inferior ・ ・ ・ ○
Heavy and inferior ・ ・ ・ ×

Abrasion resistance test: The wear of the ball seat after the writing test was measured with a running test machine with a load of 200 gf, a writing angle of 70 °, and 4 m / min.
Ball seat wear is less than 2μm and can be written.
Ball seat wear is 2 μm or more and less than 5 μm, and can be written on.
The wear of the ball seat is 5 μm or more and less than 10 μm, resulting in poor writing.
Wear of ball seat is 10μm or more, and writing becomes impossible ... ×

Ink consumption test: In an environment of temperature 20 ° C. and humidity 65% RT, a writing test is performed with a running test machine with a load of 200 gf, a writing angle of 70 °, and 4 m / min. 0 to 100 m (Y1) and 100 m before writing is completed. The ink consumption (Y2) was measured.
1.15 ≧ Y1 / Y2 ≧ 0.90 ・ ・ ・ ◎
1.20 ≧ Y1 / Y2> 1.15 or 0.90> Y1 / Y20 ≧ 0.80
Y1 / Y2> 1.20 or Y1 / Y2 <0.80

In Examples 1 to 3 , writing taste, abrasion resistance test, and ink consumption test were all good, and writing performance was good.

  In Comparative Example 1, since a compound having no aromatic ring was used, the writing was heavy and the wear of the ball seat was all severe in the wear resistance test. In addition, in the ink consumption test, the ink consumption decreased, and the handwriting became thinner and blurring occurred.

  In Comparative Example 2, since a compound having no aromatic ring was used, the writing quality was inferior, and in the abrasion resistance test, the ball seat was all worn very badly. In the ink consumption test, the ink consumption increased and the writing performance such as scratch resistance was poor.

  In Comparative Example 3, the ink viscosity was too high, the writing was heavy, and the wear of the ball seat was inferior in the wear resistance test.

  In Comparative Example 4, since a silicon surfactant which is a compound having no aromatic ring was used, the writing was heavy, and in the abrasion resistance test, the ball seat was all worn very badly, and writing was poor or impossible to write.

The present invention relates to an ink composition for an oil-based ballpoint pen, and more specifically, a ballpoint pen tip made of a stainless steel material holding a ball rotatably mounted at the tip of an ink containing cylinder, directly or via a tip holder, A ballpoint pen that contains an acidic compound having at least an aromatic ring inside the ink-holding cylinder and directly contains ink for oil-based ballpoint pens having an ink viscosity of 10 to 5000 mPa · s at 20 ° C. and a shear rate of 500 sec ⁻¹ . Ballpoint pen characterized by satisfying 1.20 ≧ Y1 / Y2 ≧ 0.80 when the refill is an ink consumption Y1 mg at 0 to 100 m and an ink consumption Y2 mg at 100 m before the end of ink Good oil-based ballpoint pen ink with good writing quality and good lubricity by using refill A composition can be provided. Therefore, it can be widely used as a ballpoint pen, such as a cap type and a knock type.

1 Ballpoint pen refill
2 Ink container
3 balls
4 Ballpoint pen tip
5 Tip end
5a Tip edge
6 ball holding room
7 Ink distribution hole
8 Radial grooves
9 Ball seat
10 Coil spring

Claims (8)

A ballpoint pen tip made of a stainless steel material having a ball rotatably held at the tip of the ink containing cylinder is mounted directly or via a chip holder, and an acidic compound having an aromatic ring inside the ink containing cylinder, It contains at least a salt-form of a basic compound having an aromatic ring and directly contains an ink for oil-based ballpoint pens having an ink viscosity of 10 to 5000 mPa · s at 20 ° C. and a shear rate of 500 sec ⁻¹ . It is a ballpoint pen refill, and satisfies 1.20 ≧ Y1 / Y2 ≧ 0.80 when the ink consumption Y1 mg at the time of 0 to 100 m and the ink consumption Y2 mg at 100 m before the end of ink are set. Ballpoint refill. The ballpoint pen refill according to claim 1, wherein the basic compound having an aromatic ring is a benzoxonium compound. The ballpoint pen refill according to claim 1 or 2 , wherein the oil-based ballpoint pen ink contains an organic amine having ethylene oxide (CH ₂ CH ₂ O). The ballpoint pen refill according to any one of claims 1 to 3, wherein an axial movement amount of the ball is 3 to 15 µm. The ballpoint pen refill according to any one of claims 1 to 4 , wherein the acidic compound having an aromatic ring has a molecular weight of 200 or more. The content of the acidic compound having an aromatic ring, ballpoint pen according to any one of claims 1, characterized in that 0.1 to 20.0 wt% 5 refill. The ballpoint pen refill according to any one of claims 1 to 6 , wherein the acidic compound having an aromatic ring is alkylbenzenesulfonic acid. The ballpoint pen refill according to any one of claims 1 to 7 , wherein the pH of the oil-based ballpoint pen ink is 4 to 10.

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