JPH1142883A - Ink follow-up material for water-based ball-point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make an ink follow-up material for a water-based ball-point pen excellent in aged stability while a residual amount of ink is made easy to be seen by making an interface plane, further a thickener in an ink follow-up material is excellent in dispersion, and separated oil is little by a method wherein a reagent which connects both chemically, or improves an affinity accompanied by chemical reaction to raise a function of a composite material, is contained. SOLUTION: A reagent wherein in a water-based ball-point pen receiving ink 20 directly in an ink receiving tube 10, silicon is contained in a molecule, and in inorganic material and organic material, or an organic material composite system of different kinds, both are chemically bonded, or an affinity is improved followed by chemical reaction, and function of composite material is raised, i.e., a silane coupling agent is limited. Thereby, fine grain thickener and a clay amount increasing agent in the ink follow-up material 30 are bonded to the silane coupling agent, and dispersion in the ink follow up material 30 becomes good. A hydrophobic property of the ink follow-up material 30 itself is improved from a hydrophobic property of that itself, and both are welded together almost in a plane from a function wherein an interface between the ink 20 and the ink follow-up material is kept at a minimum area.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink-follower composition for water-based ballpoint pens, more specifically, an ink-ink follower interface is always clear, the remaining amount of ink is easy to understand, and ink is directly stored in an ink storage tube. The present invention relates to an ink-follower composition for a water-based ball-point pen, which does not have a phenomenon that bubbles are accumulated at the interface between the ink and the ink-follower, which is unique to the water-based ball-point pen.

[0002]

2. Description of the Related Art The viscosity of an ink for an aqueous ballpoint pen is 3 Pa · sec to 20 Pa for an oil ballpoint pen having a similar form.
-In contrast to 50 mPa-sec to 3 Pa-sec, the ink leaks when the pen is left upward or sideways. In addition, since ink may be scattered even by a slight impact to stain hands and clothes, an ink follower is provided to prevent this.

JP-A-48-40510, JP-A-57-1
53070, JP-A-57-200472, JP-A-58-1982
1772, JP-A-61-57673, JP-A-61-14
5269, JP-A-61-151289, JP-A-61-2
00187, JP-A-61-268786, JP-A-62-1987
50379, JP-A-62-148581, JP-A-62-148581
199492, JP-A-63-6077, JP-A-02-2
48487, JP-A-04-202281, JP-A-05-202
270192, JP-A-05-270193, JP-A-06
-200235, JP-A-06-220418, JP-A-0-220418
6-247094, JP-A-06-264048, JP-A-06-328890, JP-A-06-336584, JP-A-07-61187, JP-A-07-173426, JP-A-07-214974, JP-A-07-214975, JP-A-07-1979 242093, JP-A-07-266780,
JP-A-08-2171, JP-A-08-11481, JP-A-08-58282, JP-A-08-72465, JP-A-08-90982, JP-A-08-108679, JP-A-08-142570, JP-A-08-183286, JP-A-08-183286 08-300873, JP-A-08-300874, JP-A-09-11683, and JP-A-09-76687, etc., use a gel-like material or a combination of a gel-like material and a solid material in an aqueous ballpoint pen in which ink is directly stored in an ink storage tube. It is disclosed that an ink follower is provided. These inventions are aimed at various purposes and eyes, such as making it easy to follow ink, withstanding the impact of falling, enhancing the effect of preventing backflow, and improving the appearance.

In Japanese Utility Model Publication No. 3-53902, the ink follower is made of polybutene that is not thickened, and the difference in the wetting of the ink and the ink follower to the ink storage tube is used to make the meniscus at the interface convex and the ink remaining amount is increased. Is easy to understand. However, in the same invention that does not provide pseudoplasticity, the ink leaks when the pen is turned sideways or upward. Further, even if a slight degree of pseudoplasticity is imparted, the meniscus cannot be reliably made convex. If the shape of the interface can be reliably made to be convex, it can be made surely a plane.When considering the transparency of the ink storage tube and the ink follower, the shape of the interface should be a plane. It is obvious that one person can easily determine the remaining amount of ink.

Further, since the ink follower for water-based ball-point pens has low viscosity, there is a disadvantage that the oil component is likely to separate (oil separation) when left unattended. This is because the amount of ink required for writing with an oil-based ballpoint pen is 100 m
On the other hand, in the case of an aqueous ballpoint pen in which ink is directly stored in the ink storage tube, the amount of ink required for writing is as large as about 50 to 300 mg per 100 m. As required, those with low consistency become the mainstream. In general, the lower the viscosity of lubricating grease, the lower the stability and the more likely it is for oil release to occur. Further, since the thickener component easily moves in the lubricating grease, a sparse part and a dense part are mixed, and it is easy to lose the uniform state. Since the ink follower for the water-based ballpoint pen uses a material similar to the lubricating grease, it exhibits a time-dependent behavior based on a similar physical law. However, if oil separation occurs, it reacts with the surfactant in the ink or breaks the ink flow path as oil droplets, which adversely affects writing. In addition, if there is no uniformity, a part to be followed and a substance that adheres granularly to the inner wall of the ink storage tube will be formed, which not only makes the appearance worse, but also reduces the amount by the amount attached to the inner wall, and finally prevents volatilization and leakage. Also, the function as a follower of such as will be lost.

SUMMARY OF THE INVENTION The present inventors have improved such a disadvantage and provided a pseudo-plasticity ink follower composition in which the ink remaining amount is easy to see with an interface as a flat surface and the oil release is difficult to remove. We did intensive research to provide things. JP-A-8-300873 discloses an ink follower for an aqueous ballpoint pen using a silane-based surface modifier.
In the present invention, in particular, in an inorganic material and an organic material, or in a heterogeneous organic material composite system, a chemical agent that combines the two chemically or improves the affinity with a chemical reaction to enhance the function of the composite material, that is, It is limited to a silane coupling agent. As a result, the fine particle thickener and the clay thickener in the ink follower combine with the silane coupling agent to improve the dispersion in the ink follower, and furthermore, the hydrophobicity of the ink follower itself increases due to its own hydrophobicity. From the effect of improving the performance and keeping the interface between the ink and the ink follower in a minimum area, it has been found that both are brought into close contact with a substantially flat surface, and based on this finding, the present invention has been completed.

In the present invention, the amount of the coupling agent is 0.1 to 20.0 parts by weight based on the total amount of the composition.
Furthermore, 0.1 to 5 parts by weight is preferred. If the amount is less than 0.1 parts by weight, the effects of the present invention cannot be obtained. If the amount exceeds 5 parts by weight, the excess coupling agent oozes out of the ink follower and floats in the ink, and in the worst case, adversely affects the ink material such as pigment. 2
If the amount exceeds 0 parts by weight, the amount of bleeding is large, and the ink flow path may be completely blocked when the pen tip is stored upward for a long period of time.

Solvents used as base oils for ink followers for aqueous ballpoint pens include mineral oils such as polybutene, liquid paraffin and spindle oil, and silicone oils. They do not elute into the aqueous ink and have a small loss on evaporation. In addition, in general, water-based ink has better wettability with resins such as polypropylene and polyethylene used for an ink storage tube than an aqueous ink, and has an advantage that the amount of consumed ink can be easily recognized.

[0009] Some polybutenes and silicone oils have high volatility.
The volatilization loss value was measured at 8 ° C. for 5 hours.
If it is 2% by weight or less, there is no problem at room temperature for 2 to 3 years or more. The volatility of polybutene correlates strongly with molecular weight. When the standard for satisfying the above-mentioned volatilization loss value is represented by a molecular weight, a substance having an average molecular weight of about 500 or more corresponds to the standard. Since the structure of the silicone oil is also an important factor, it cannot be determined solely from the molecular weight alone.

The thickener and surfactant used in the ink follower for water-based ballpoint pens are usually preferably hydrophobic or water-insoluble. When hydrophilic thickeners and surfactants migrate into the ink from the interface with the ink, causing the ink follower to lose its viscosity or adversely affecting the ink, resulting in inconvenience such as being unable to write. There is. Examples of the thickener include Aerosil R-972, R-974D, and R-976.
D, RY-200 (Nippon Aerosil Co., Ltd. brand name) fine particle silica whose surface is methylated, Leopard KE
Organic thickener such as (trade name of Chiba Flour Milling Co., Ltd.), clay thickener whose surface is hydrophobized by onium treatment such as dimethyldioctadecyl ammonium bentonite, lithium stearate, aluminum stearate, sodium stearate, etc. Use of a water-insoluble metal soap. These may be used alone or in combination, but their total amount is 1 to 10% by weight based on the total amount of the ink follower. Further, in the present invention, an effect of improving the hydrophobicity of the entire ink follower system is obtained by the effect of the coupling agent, so that Aerosil # 200,
380, 300, 100, OX50 (Nippon Aerosil Co., Ltd.)
(Product name) Hydrophilic thickeners such as fine-particle alumina and ultrafine-particle titanium oxide can also be used. The amount used is equivalent to the hydrophobic one.

It is also an effective means to use an additive such as a surfactant in order to improve the follow-up property of a usual ink follower for a water-based ballpoint pen. The type of the surfactant is not limited, but it is not preferable that the gel on the ink side elutes into the ink during storage over time, and a nonionic surfactant having an HLB (hydrophilic / hydrophobic balance) value of 4 or less is preferable. . Furthermore, what is generally called a fluorine-based surfactant or a silicon-based surfactant is most preferable because it significantly lowers the surface tension of the base oil. Additives that are effective in stabilizing and homogenizing the dispersion of the thickener and making the system hydrophobic are to be used positively as long as they do not adversely affect the stability over time or the ink. In the present invention, it is possible to use an additive having some hydrophilicity for the same reason as the above-mentioned thickener. Generally, the amount of these additives ranges from 0.01%, which is the minimum amount at which the effect is exerted, to about 5% by weight at the maximum. When used in an amount exceeding 5% by weight, there is no problem in the performance of the ink follower itself, but the effect of addition is not only completely meaningless, but also there is a concern about adverse effects on the ink.

It is preferable to add the additives in advance because they are easily distributed uniformly throughout the entire system, but there is no problem in changing the order of addition as necessary. For example, when metal soap is used, it must be kneaded by heating to a high temperature of 200 ° C. or higher, and the additive loses its effectiveness unless added after cooling according to its heat resistance.

An example of the method for filling the ink follower according to the present invention is as follows. An ink is filled into an ink container, a pen point is attached, and the ink follower is further filled. Thereafter, when a strong centrifugal force is applied from the tail end toward the pen tip by the centrifugal separator, the ink and the ink follower are filled with good appearance without air or the like being interposed therebetween.

Next, the present invention will be described with reference to examples.

For evaluation of the examples and comparative examples, aqueous ballpoint pen inks were prepared as follows. Printex 25 (Carbon Flack; trade name of Degussa Co., Ltd.) 6 parts by weight Joncryl 61J (styrene acrylic acid copolymer emulsion: 31% ammonia neutralized aqueous solution: Johnson Co., Ltd.) 10 @ Acronal YJ-1120D (styrene methacryl) Acid copolymer: 50% emulsion: trade name of Mitsubishi Chemical BASF Corporation 10 glycerin 10 potassium ricinoleate 0.5 triethanolamine 1 1,2-benzisothiazolin 3-one 0.2 benzotriazole 0.2 {SILWET L7001 (Silicone-based surfactant; trade name of Nippon Unicar Co., Ltd.)} 0.2 {Water 11.5} After kneading the above with a bead mill, coarse particles of carbon black were removed and propylene glycol 20 parts by weight. Carbopol 940 (cross-linked type (Liacrylic acid; BF CUT (trade name of Rich Co., Ltd.)) 0.4 {water 30} was added to obtain an ink for a ball-point pen having a viscosity of 450 mPa · sec at 40 sec ^-1 .

Test 1 Stability over Time (Pen Body Storage Test) Each of 50 examples and comparative examples was assembled into a ballpoint pen shown in FIG. A translucent polypropylene tube having an inner diameter of 4.0 mm was used as an ink storage tube 7 and filled with a predetermined ink 8 and an ink follower 9 of each of Examples and Comparative Examples. A commercially available ballpoint pen (UM) having the same configuration as that of FIG.
-100; the same ballpoint pen tip as that of Mitsubishi Pencil Co., Ltd.). The ball-point tip holder 3 is made of free-cutting stainless steel, and the ball 4 is made of tungsten carbide having a diameter of 0.5 mm. A storage test was performed on the assembled ballpoint pen under forced conditions. After leaving each sample in a constant temperature bath at 50 ° C. for 2 weeks with the pen tip facing upward, the number of oils in the ink was counted by silent gaze and scored. Examples and comparative examples each have 50 samples, with 0 being the best and 50 being the lowest.

Test 2 Written test Ten samples each of which were the same as in Test 1 were assembled, and spiral writing was performed continuously at a speed of 4.5 m / sec at a speed of 4.5 m / sec to consume approximately half of the initial ink amount. The remaining amount of ink was visually confirmed, and the ink remaining amount was easy to understand as in the initial stage. Although the remaining amount is easy to understand, the ink / ink follower interface is not flat. A point where the inner wall of the ink storage tube was extremely dirty was designated as one point. Nothing on the way loses the function of the ink follower
As a point, I was going to change from the formulation design, but there was no 0 point this time.

The vinyltris (β-methoxyethoxy) silane used in this test was KBC1003 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.) and TSL835 (trade name, manufactured by Toshiba Silicone Co., Ltd., γ-glycidoxypropyltrimethoxysilane).
0, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane is a trade name of Nippon Unicar Co., Ltd.
1120, diphenyldiethoxysilane used was a brand name KBE202 manufactured by Shin-Etsu Chemical Co., Ltd.

(Example 1) Nissan polybutene 015N (trade name of Nippon Oil & Fats Co., Ltd.) 94 parts by weight Fine particle aluminum oxide (manufactured by Nippon Aerosil Co., Ltd.) 5 {vinyltris (β-methoxyethoxy) silane 1} Example 1 was obtained by kneading with a three-roll mill.

(Example 2) KF-96A-3,000 (methylpolysiloxane: trade name of Shin-Etsu Chemical Co., Ltd.) 95 parts by weight Aerosil 380 (fine particle silica; trade name of Nippon Aerosil Co., Ltd.) 3３γ-glycidic Xylpropyltrimethoxysilane 1 {SILWET FZ2110 (silicone surfactant; trade name of Nippon Unicar Co., Ltd.) 1} The above mixture was kneaded with a three-roll mill to obtain Example 2.

Example 3 Polybutene HV-15 (trade name of Nippon Oil Co., Ltd.) 89.9 parts by weight Aerosil R974 (trade name of Nippon Aerosil Co., Ltd.) 4 N- (β-aminoethyl) -γ- Aminopropyltrimethoxysilane 6 {F Top EF-801 (Fluorine-based surfactant; trade name of Mitsubishi Materials Corporation) 0.1} The above compound was kneaded with a three-roll mill to obtain Example 3.

Example 4 Diana Process Oil MC-W90 56 parts by weight Polybutene HV-15 32 {Aerosil R974 3} Vinyl tris (β-methoxyethoxy) silane 6} N- (β-aminoethyl) -γ-aminopropyltri Methoxysilane 3 @ The inside was reduced to 0.1 atm with a planetary mixer (manufactured by Kodaira Seisakusho) and stirred for 2 hours to obtain Example 4.

(Example 5) KF-96H-30,000 (methylpolysiloxane: trade name of Shin-Etsu Chemical Co., Ltd.) 37 parts by weight Diana Process Oil MC-S32 53 {Aerosil 200 1} Benton 34 (organic treated bentonite: Wilvar-Eris Co., Ltd.) 2 {vinyl tris (β-methoxyethoxy) silane 6} diglycerin dibehenyl ether 1 {ethanol 2} The above mixture was kneaded twice with a three-roll mill.
The ethanol was volatilized and lost during kneading on a three-roll mill.

(Comparative Example 1) Nissan polybutene 015N 95 parts by weight Fine aluminum oxide 5% The above compound was kneaded with a three-roll mill to obtain Comparative Example 1.

(Comparative Example 2) KF-96A-3,000 95 parts by weight Aerosil 380 3 {SILWET FZ-2110 1} NIKKOL SO-15 (Nikko Chemical {trade name: Sorbitan sesquiolate) 1} Comparative Example 2 was obtained by kneading with a roll mill.

Comparative Example 3 89.9 parts by weight of polybutene HV-15 Aerosil R974 4 {KF-96A-3,000 6} F Top EF-801 0.1} The above compound was kneaded with a three-roll mill and compared. Example 3 was obtained.

(Comparative Example 4) Diana Process Oil MC-W90 59 parts by weight Polybutene HV-15 32 {Aerosil R974 3} NIKKOL SO-15 3} Reduce the pressure to 0.1 atm with a planetary mixer (described above). After stirring for 2 hours, Comparative Example 4 was obtained.

(Comparative Example 5) KF-96H-30,37 parts by weight Diana Process Oil MC-S3253 {Aerosil 2001} BENTON 342 {KF-96A-3,000 6} Diglycerin dibehenyl ether 1} Ethanol 2} The above composition was kneaded twice with a three-roll mill, and Comparative Example 5
The ethanol was volatilized and lost during kneading on a three-roll mill.

Comparative Example 6 Diana Process Oil MC-W90 56 parts by weight Polybutene HV-15 32 {Aerosil R974 3} Diphenyldiethoxysilane 9 # Reduce the pressure to 0.1 atm with a planetary mixer (described above) for 2 hours. After stirring, Comparative Example 6 was obtained.

Table 1 shows the test results of Examples and Comparative Examples.

[0031]

[Table 1]

In Examples 1 to 5, no oil separation was observed. In particular, Example 1 and Comparative Example 1 differ only in the presence or absence of the silane coupling agent. In Comparative Example 1, the aluminum oxide fine particles having high hydrophilicity migrated into the ink, and all the oil components were moved in the tip direction ( (In the upward direction), but was not seen at all in Example 1. This is probably because the silane coupling agent increased the hydrophobicity.

The inks of Comparative Example 2 and Comparative Example 3 had good follow-up properties with the respective silicone-based and fluorine-based surfactants exhibiting the effect. "The interface after writing was flat. Did not meet the strict criteria of "things." On the other hand, in Example 2 in which the silane coupling agent was added, the interface remained flat in all of Example 10 and 6 out of 10 in Example 3.

In Example 4, there was no oil separation and the ink followability was good even though the dispersion was performed with a lower shearing force than in the other examples. On the other hand, in Comparative Example 4 in which no silane coupling agent was added, good results were not obtained despite the use of hydrophobic silica and a surfactant having an HLB value of 3.7. This means that the silane coupling agent functioned well as a dispersant. As an additional test, Comparative Example 6 using diphenyldiethoxysilane, which is a silane-based surface modifier, was prepared. Since the hydrophobicity is improved, it is effective in transferring oil droplets into the ink. There was no improvement in followability.

Further, vinyltrichlorosilane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3,4
Epoxycyclohexyl) ethyltrimethoxysilane,
γ-glycidoxypropyltrimethoxysilane, N-β
(Aminoethyl) γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane The same test as in this example was performed in combination, but all showed the same tendency.

For reference, polybutene, liquid paraffin, spindle oil, dimethyl silicone oil and methyl phenyl silicone oil are used as base oils, and Aerosil R-972, R-974D, R-976D, RY-2 are used as thickeners.
00, # 200, 380, 300, 100, OX50,
TITANIUM DIOXIDE P25, ALMINIUM OXIDE (Nippon Aerosil Co., Ltd. product name) BETON 27, 34, EW (Wilbaelis Company product name), Synthetic smectite SAN, SA
F, SWN (Coop Chemical Co., Ltd.) and other additives such as fluorine-based and silicon-based surfactants such as polyoxyethylene derivatives, glycerin / polyglycerin derivatives, sorbitan derivatives, and phosphate esters; aluminum-based coupling agents; Tests in which a titanium-based coupling agent was arbitrarily combined showed the same tendency as in the examples of the present application.

[0037]

As described above, according to the present invention, the ink follower provided with the pseudo-plasticity allows the ink remaining amount to be easily viewed with the interface being flat, and the thickener in the ink follower is well dispersed and oil release is improved. It is an ink follower for water-based ballpoint pens that is small and has excellent stability over time.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a refill holder of an aqueous ballpoint pen using the ink follower of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 ink storage tube 20 ink 30 ink follower 40 joint between pen tip and ink storage tube 41 pen tip (ballpoint pen tip holder) 42 ball

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Miki Sugiyama 2-12-12 Irie, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture Inside Mitsubishi Pencil Co., Ltd. Yokohama Office (72) Inventor Katsuhiko Shiraishi 2-chome Irie, Kanagawa-ku, Yokohama-shi, Kanagawa 5-12 Mitsubishi Pencil Co., Ltd. Yokohama Office

Claims (2)

[Claims] 1. An aqueous ball-point pen for directly storing ink in an ink storage tube, wherein the compound contains silicon in a molecule and is composed of an inorganic material and an organic material or a heterogeneous organic material composite system.
An ink follower characterized by containing a reagent that chemically links the two or improves affinity with a chemical reaction and enhances the function of the composite material 2. In a composite system of an inorganic material and an organic material or an organic material of a different kind, a reagent which chemically bonds the two or improves affinity with a chemical reaction to enhance the function of the composite material is provided. Vinyltrichlorosilane, vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3,4 epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxy Propyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β
(Aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N.
Phenyl-γ-aminopropyltriethoxysilane, γ
The ink follower according to claim 1, wherein the ink follower is at least one compound selected from the group consisting of -mercaptopropyltrimethoxysilane and γ-chloropropyltrimethoxysilane.