JPH01299880A - Oil-base ink for ballpoint pen - Google Patents

Abstract

PURPOSE:To obtain the title ink having features of also a water-base ink for a ballpoint pen, can give a nonblotting, spotless and beautiful writing and is freed of a problem of a leak of ink from a penpoint, by using at least a colorant, an organic solvent and a viscosity modifier as essential components and specifying the viscosity of the obtained ink. CONSTITUTION:This ink compriser at least a colorant which is a well-known dye (e.g., Victoria Blue FB), an organic solvent of a surface tension at 25 deg.C >=30dyne/cm (e.g., benzyl alcohol, phenyl Cellosolve or propylene glycol) and a viscosity modifier soluble in said solvent (e.g., hydroxypropylcellulose or polyvinylpyrrolidone). A dissolution aid (e.g., isopropanol), a dispersant, etc., are optionally added to the obtained mixture to adjust its viscosity in the range of 50-2000cP.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an oil-based ink for ballpoint pens, and more particularly to an oil-based ink for ballpoint pens that has the features of conventional oil-based inks for ballpoint pens and water-based inks for ballpoint pens. It is something.

(Prior Art) Conventionally, inks for ballpoint pens include low-viscosity water-based inks for ballpoint pens that use water as the main solvent and have an ink viscosity of several centipoise, and ink viscosity of several 1000 to several 10 centipoise.
Oil-based inks for ballpoint pens with a high viscosity of 1,000 centiponds and a high boiling point organic solvent as the main solvent are known, and each of the above-mentioned water-based and oil-based inks for ballpoint pens has features that other inks do not have. have.

In other words, water-based ink for ballpoint pens has a low viscosity, so you can get beautiful handwriting without any blemishes, and oil-based ink for ballpoint pens has a high viscosity, so you can get beautiful handwriting without smearing, and it can also be used with small diameters. Since the ink storage tube can be filled directly, the amount of ink remaining can be checked by making the ink storage tube a transparent material.

(Problems to be Solved by the Invention) However, although the water-based and oil-based inks for ballpoint pens have the above-described advantages, they also have the following disadvantages. In other words, because water-based ink for ballpoint pens has a low viscosity, handwriting tends to smear, and in order to prevent ink leakage, a structure with an ink absorbing body such as a fiber bundle must be adopted, and ink remains. The amount cannot be confirmed, and oil-based ink for ballpoint pens has a high viscosity, so it is slow to penetrate the writing surface, and when writing, a portion of the ink tends to remain on the tip of the pen tip, which tends to cause smudges in the handwriting. It is.

Therefore, the inventor of the present invention has found that it is possible to obtain beautiful handwriting without blemishes, which is a feature of conventional water-based ink for ballpoint pens, and also to obtain handwriting without smearing, which is a feature of conventional oil-based ink for ballpoint pens. As a result of various studies in order to obtain an oil-based ink for ballpoint pens that also has the advantage of allowing the remaining amount of ink to be checked, we have developed a ballpoint pen that can achieve the above objectives when the ink viscosity is adjusted within the range of 50 to 2000 centipoise (25°C). We have obtained knowledge that allows us to obtain oil-based ink for use in commercial use.

However, when the viscosity of the ink was simply set within the above range using a viscosity modifier or the like, and the ink was directly filled into a ballpoint pen and stored, a new problem occurred in that the ink began to leak from the pen tip.

That is, since conventional oil-based ink for ballpoint pens has a high viscosity, it has low fluidity and does not cause ink leakage even when directly filled into a small diameter ink storage tube.

Conventional water-based inks for ballpoint pens have low viscosity, but because they use ink storage bodies such as fiber bundles, ink leakage does not occur.

(Means for solving problems) The present invention comprises at least a colorant, an organic solvent, and a viscosity modifier, and the ink viscosity is adjusted to 50 to 2000 centipoise (
25° C.), the surface tension of the organic solvent is 30 d y n e /
The gist of this invention is an oil-based ink for ballpoint pens characterized by having a temperature of at least cm (25° C.).

The present invention will be explained in detail below.

The colorant is a conventionally known dye.

It can be used without particular limitation, and specifically, CI Solvent Yellow 2. Same 4゜ Same 14. Same 19.
Same 21. 56. 61. CI Solvent Orange 1.
Same 5. 37. Same 40, CI Solvent Red 1. Same 3
．． Same 8. Same 23, same 30. 81. 82. Same 109.
CI Solvent Violet8. Same 21. 27°CI
Solvent blue 2. Same 11. Same 12. 25, 35
．． 36. 55. Same 73. CI Solvent Green 3
．． CI Solvent Brown 20. 37. CI Solvent Black 3° 5. Same 7. Same 22. Same 23. Organic salt of CI Paysic Yellow 2, CI Paysic Orange 2
Organic salt of CI Paysic Red 1.

Oil-soluble dyes such as organic salts of CI Paysic Violet 3, organic salts of CI Paysic Blue and 26, organic salts of CI Paysic Green 1, and CI Direct Yellow 4. 26. 44, 50. CI Direct Red 1. Same 4゜ Same 23. 37. 39. 75. 81.
CI Direct Blue 1. Same 6. Same 15. Same 86゜ Same 1
06. 199. CI Direct Black 19. Same 2
2. 32. 38. Direct dyes such as 51 and CI Acid Yellow 9. Same 17゜ Same 19. Same 23. 25. 36. Same 42. CI Acid Orange 19. 20. 45. 56, CI Acid Red 7, 14. Same 18th
゜Same 50. Same 51. Same 52. Same 87. Same 92. Same 94,
97. CI Assist Violet 1゜Same 3. Same 7. Same 10. Same 14. CI Acid Blue 1. Same 7. Same 9. Same 15. Same 22. Same 25° Same 27. Same 74. 90. Same 9
3. CI Acid Green9. CI acid black 2
．． 24, 26. 29. Same 52. Acidic dyes such as 154, CI Paysic Yellow 1. Same 2゜ Same 11. C
I-paysik orange 2. Same 14゜ Same 15. Same 21. Same 22. CI Pacific 2. Same 8. Same 9. Same 12.
Same 13. CI Pacific Violet 1. Same 3. Same 7.
Same 10゜ Same 14. CI Paysik Blue 3. Same 5. Same 7
゜Same 9. Same 24. 25. 26. CI Paysik Green 1. Same 4. Examples include basic dyes such as CI Paysic Brown 1 and CI Paysic Black 2, which can be used alone or in combination.
It is preferably 3 to 20% by weight based on the total amount of ballpoint pen ink.

The organic solvent is used as a solvent or dispersion medium for the above-mentioned colorant and as a solvent for the viscosity modifier described below. In order to make oil-based ink for ballpoint pens without ink leakage, its surface tension must be 30
It is necessary to use dyne/am (25°C) or higher, and specifically, benzyl alcohol (38 dy
ne/cm, same below 25℃), ethylene glycol (46 dyne/cm), diethylene glycol (48 dyne/cm),
dyne/cm), propylene glycol (72 dyne/cm), propylene glycol (72 dyne/cm),
e/Cm), dipropylene glycol (32dyne/
cm), polyhydric alcohols such as glycerin (63 dyne/cm), and phenyl cellosolve (46 dyne/cm).
m), glycol ethers such as methyl calpitol (35 dyne/am), ethyl calpitol (32 dyne/am), butyl calpitol (34 dyne/cm), diethyl calpitol (32 dyne/cm), and cellosolve acetate (32 dyne/cm). a m)
Nitrogen-containing compounds such as, 2-pyrrolidone (47 dyne/cm), and N-methylpyrrolidone (41 dyne/cm) are used alone or in combination.

As the viscosity modifier, substances soluble in the above organic solvents are used, specifically methylcellulose, ethylcellulose, and hydroxycellulose.

Cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose, and carboxymethyl cellulose, polyvinyl derivatives such as polyvinylpyrrolidone, polyvinyl butyral, and polyvinyl acetal, copolymers such as styrene-maleic acid copolymer, styrene-acrylic acid copolymer, etc. , alkyd resins and modified products thereof,
Melamine resins and modified products thereof, phthalic acid resins and modified products thereof, maleic acid resins and modified products thereof, acrylic acid resins and modified products thereof.

Methacrylic acid resins and modified products thereof, vinyl acetate resins and modified products thereof, ketone resins and modified products thereof, phenol resins and modified products thereof, etc. are used alone or in combination, and the amount used depends on the type of viscosity modifier. Although it varies greatly depending on the degree of polymerization, it is 0.0% based on the total amount of ballpoint pen ink.
1 to 30% by weight is preferred.

Further, the oil-based ink for ballpoint pens of the present invention has a viscosity of 2
At 5°C, the essential requirement is 50 to 2000 centipoise. If the ink viscosity is less than 50 centipoise, ink leakage is likely to occur even if a solvent with a surface tension of 30 dyne/cm or more (at 25°C) is used, and handwriting is likely to bleed, and if it exceeds 2,000 centipoise, handwriting is likely to bleed. This is because smudges are more likely to occur.

In addition to the above essential ingredients, it also improves handwriting dryness and/or
Or methanol as a solubilizing agent.

Ethanol, isopropanol, normal butanol,
Solvents such as low-boiling alcohols such as secondary butanol, esters such as ethyl acetate and methyl acetate, aromatic hydrocarbons such as toluene and xylene, and aliphatic hydrocarbons such as n-heptane and n-hexane are added to 10% of the total amount of ink. It may be added within a range of % by weight or less, and furthermore, conventionally known surfactants, dispersants, preservatives, antifungal agents, lubricants, etc. may be appropriately selected and added.

In order to obtain this oil-based ink for ballpoint pens, the above components are obtained by heating, dissolving, mixing and stirring as necessary, and processes such as filtration and centrifugation are introduced into the ink manufacturing process as necessary. You can also do that.

(Function) Why is the oil-based ink for ball-point pens according to the present invention capable of producing beautiful handwriting without smudges or smudges, which has the features of conventional oil-based inks for ball-point pens and water-based inks for ball-point pens?
In addition, it is possible to check the remaining amount of ink, and whether ink does not leak from the pen tip is surmised as follows.

In other words, this oil-based ink for ballpoint pens has an ink viscosity of 50 to 2000 centipoise (25°C), so compared to conventional oil-based inks for ballpoint pens, the ink is quickly absorbed by the writing surface and the ink adhering to the ball is removed. Since it is completely transferred to the writing surface, smudges are less likely to occur, and since it has a higher viscosity than conventional water-based inks for ballpoint pens, the occurrence of smudging can be suppressed. Furthermore, since an organic solvent with a surface tension of 30 dyne/cm or more is used, the surface tension of the ink will also be high, so ink with the above viscosity range can be directly filled into a small diameter ink storage tube. Also, there is no ink leakage, and the remaining amount of ink can be checked.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples, where "parts" in Examples and Comparative Examples indicate "parts by weight."

Lost garden disaster Victoria Blue FB 10
= 0 copies (CI Paysic Blue 26. BASF
) Isopropanol 3.15 parts Glycerin 30.0 parts Ethylene glycol 50.0 parts HPC (H)
, 1.6 parts (hydroxypropylcellulose.

(manufactured by Nippon Soda ■) Benzotriazole (preservative> 0.05 part After mixing the above ingredients, stirring for 2 hours while heating to 70°C,
The mixture was filtered through a 1 μm filter to obtain a blue oil-based ballpoint pen ink having a viscosity of 1220 centivoise (25° C.).

Tsutomu Kaikakasa In the above Example 1, except that HPC (H) was 0.4 parts and ethylene glycol was 51.4 parts.

As in Example 1, the viscosity was 40 centipoise (25°C
) was obtained as an oil-based ink for blue ballpoint pens.

Blue ballpoint pen with a viscosity of 2430 centipoise (25°C) except that RPC (H) was 2.2 parts and ethylene glycol was 49.6 parts. An oil-based ink for use was obtained.

In Example 1 above, ethylene glycol was replaced with butyl cellosolve (surface tension: 27 dyne/cm).

Same as Example 1 except that the temperature was 25°C).

A blue oil-based ballpoint pen ink having a viscosity of 1150 centipoise (25° C.) was obtained.

Shiran Somata Spiron Red C-GH 10.0 parts (organic salt of CI Paysic Red manufactured by Hodogaya Chemical Industry) Benzyl alcohol 20.0 parts Phenyl cellosolve 25.0 parts Propylene glycol 9.95 parts PVP K2O 8.0 parts ( Polyvinylpyrrolidone, manufactured by BASF) PVP K
0 parts of 2O (polyvinylpyrrolidone, manufactured by BASF) After mixing the above components, the mixture was stirred at room temperature for 3 hours and filtered through a 1 μm filter to obtain a red oil-based ballpoint pen ink with a viscosity of 230 centipoise (25° C.).

Loss of Five Lords Nigrosine Base EX 15.0 parts (CI Solvent Black 7, manufactured by Orient Kagaku Kogyo ■) Benzyl Alcohol 10.0 parts Phenyl Cellosolve 55.0 parts Hilac llOH
5.0 parts (ketone resin, manufactured by Hitachi Chemical ■) Denka Butyral #4000-1 15.0 parts (butyral resin, manufactured by Denki Kagaku Kogyo ■) The above components except for nigrosine base EX were mixed and mixed at room temperature. After stirring for 1 hour, Nigrosine Base EX was further added, and the mixture was further stirred at room temperature for 1 hour and filtered through a 1 μm filter to obtain a black oil-based ballpoint pen ink with a viscosity of 1640 centipoise (25° C.).

Lost Garden Carbon Black 10.0 parts Isopropanol 5.0 parts Ethyl Calpitol
65.0 parts nitrocellulose
15.0 parts MP-10005.0 parts (methacrylic acid copolymer, manufactured by Soken Kagaku ■) Among the above components,
The components except carbon black were mixed, stirred at room temperature for 1 hour, transferred to a ball mill pot, carbon black was added thereto, mixed and dispersed for 24 hours, filtered through a 1 μm filter, and the viscosity was 640 centipoise (at 25°C). )
A black oil-based ink for ballpoint pen was obtained.

Kansoso and Copper Phthalocyanine Blue 15.0 parts (organic pigment) N-methylpyrrolidone 65.0 parts Isopropatol 5.0 parts Joncryl 672
15.0 parts (styrene-acrylic copolymer,
(manufactured by Johnson ■) The above ingredients except copper phthalocyanine blue were mixed, stirred at room temperature for 1 hour, and then transferred to a ball mill pot.
Copper phthalocyanine blue was added to this, mixed and dispersed for 36 hours, filtered through a 1 μm filter, and the viscosity was 450.
A centipoise (25° C.) blue oil-based ink for ballpoint pens was obtained.

(Effect of the invention) The ballpoint pen oil-based inks obtained in Examples 1 to 5 and Comparative Examples 1 to 2 above were filled into a transparent resin cylinder with an inner diameter of 3 mm, and a stainless steel cylinder with a 0.5 mm diameter carbide ball set at the tip. Combine the ballpoint pen tip to make a test ballpoint pen 1
A quality test was conducted. The results are shown in Table 1.

(The following is a margin) Table 1 *1 Bottles: Using the above-mentioned ballpoint pen for testing, a writing tester (manufactured by HUTT) was used to write over a distance of 100 m, and the number of blots was measured.

o: 0~2 Δ: 3~10 ×: 11 or more Car 2 Niji Mini JIs with the above test ballpoint pen
Handwritten notes were written on P3201 writing paper A, and the state of the handwriting was observed.

0: No bleeding ×: There is bleeding *3 Ink leakage: Hold the ballpoint pen with the tip facing downwards. 5
The pen was allowed to stand for a minute, and leakage of ink from the pen tip was observed.

0: No ink leakage X: Ink leakage As explained in detail above, the oil-based ink for ballpoint pens according to the present invention provides beautiful handwriting without any smudges or smudges, and the remaining amount of ink can be confirmed. This is an excellent oil-based ink for ballpoint pens that combines the features of conventional water-based inks for ballpoint pens and oil-based inks for ballpoint pens.

Claims (1)

[Claims] consisting of at least a colorant, an organic solvent, and a viscosity modifier,
An oil-based ink for a ball-point pen having an ink viscosity in the range of 50 to 2000 centipoise (25°C), characterized in that the surface tension of the organic solvent is 30 dyne/cm (25°C) or more.