JP2003103986A - Ink backflow inhibitor composition for ball-point pen - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink backflow inhibitor composition for a ball-point pen with upgraded high temperature performance, follow-up properties and resistance to impact and mixing. SOLUTION: This ink backflow inhibitor composition for a ball-point pen is composed of a urea composition added, as a thickening agent, to a hard volatile liquid. The content of the urea composition is 0.1 to 40 mass% for the hard volatile liquid of a base oil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink backflow preventive composition for a ballpoint pen which prevents the ink filled in the ink cylinder of a ballpoint pen from flowing back from the open side of the ink cylinder.

[0002]

2. Description of the Related Art A ball-point pen has a ball-point pen tip at one end of an ink cylinder and an open other end. If the ink cylinder is simply filled with ink, the ball-point nib can be directed upward, sideways, or the like. If left unattended, the ink will flow back through the ink cylinder and leak from the ink cylinder, or even a slight impact of the ink will leak from the ink cylinder and the ink will scatter and stain clothes and the surrounding environment. There is a risk that In addition, the ink filled in the ink cylinder may evaporate through the opening side. In order to prevent these undesired phenomena, the ink pen is filled with a composition called an ink backflow preventer or an ink follower in contact with the ink end surface in the ink cylinder.

The ink backflow preventive composition for ballpoint pens is required to have the following properties. That is, the ink backflow inhibitor composition for a ballpoint pen has high temperature performance, followability,
Impact resistance and mixing resistance are required. As for high-temperature performance, the ink filled in the ink cylinder has the property that the base oil and gelling agent do not separate even in the atmosphere of about 80 ° C that is encountered during transportation of a ballpoint pen, and moreover, it flows in the ink cylinder. Alternatively, it is required that the ink does not flow out from the cylinder. As for the followability, the ink will be consumed as the ballpoint pen is used, but the ink backflow preventive composition will follow the ink end face as it is consumed, and moreover, it will adhere to the wall surface of the ink cylinder and stick to the ink cylinder. It is required not to remain at the end of the section. The impact resistance is required to have a property such that the ink does not flow in the ink cylinder or the ink does not flow out from the ink cylinder even if the ballpoint pen is impacted by being dropped. Further, as the mixing resistance, it is required that the composition for preventing backflow of ink for ballpoint pens is mixed with the ink for oil-based ballpoint pens or the ink for water-based ballpoint pens and does not contaminate the composition for backflow prevention of ink.

[0004]

As described above, various compositions have been disclosed so far as the ink backflow preventive composition, but in recent years, the composition of the ink, the diameter of the ink cylinder portion, etc. have been varied. Under the present circumstances, the ink backflow inhibitor composition for ballpoint pens is not always able to satisfy all of the above-mentioned high temperature performance, followability, impact resistance and mixing resistance.

Therefore, an object of the present invention is to solve the above-mentioned problems, and by appropriately selecting the composition of the thickener for the hardly volatile liquid, excellent high temperature performance, followability, It is an object of the present invention to provide an ink backflow preventive composition for a ballpoint pen having all the properties of impact resistance and mixing resistance.

[0006]

SUMMARY OF THE INVENTION The present invention relates to an ink backflow preventive composition for ball-point pens, which comprises adding a urea composition as a thickener to a hardly volatile liquid.

In the composition for preventing backflow of ink for a ballpoint pen, the content of the urea composition is in the range of 0.1% by mass to 40% by mass.

The urea composition as the thickener has a general formula of R'-NHCONH-R-NHCONH.
It is a compound of -R '. In the above general formula, R is a divalent hydrocarbon compound having 2 to 20 carbon atoms and its derivative, and R'is a monovalent hydrocarbon compound having 1 to 20 carbon atoms and its derivative. Further, R is a tolylene group, a diphenylmethane group, a ditolylene group or a naphthalene group, R'is an alkyl group, a cycloalkyl group, an aryl group or a combination thereof, and an alkyl group is an octyl group, a dodecyl group, a hexadecyl group or an octadecyl group, a cyclo group. The alkyl group is a cyclohexyl group, an ethylcyclohexyl group or a dicyclohexyl group, and the aryl group is a phenyl group, a diphenyl group, an ethylphenyl group or an ethoxyphenyl group.

The refractory liquid is 100 to 1 at 25 ° C.
Silicone oil having a kinematic viscosity of 00000 mm ² / s,
It is one or more of refined mineral oil, synthetic oil, and polybutene oil having a kinematic viscosity of 100 to 10,000 mm ² / s at 40 ° C.

This ink backflow inhibitor composition for ballpoint pens has a 1-minute value of 2 on a spread meter at 25 ° C.
It is 0 to 50 mm.

Since the ink backflow preventive composition for ballpoint pens is constructed as described above, the ink followability and mixing resistance are improved, and the high temperature performance and impact resistance are excellent. Sex is greatly improved.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Examples of the ink backflow preventing composition for ballpoint pens according to the present invention will be described below.

The ink backflow preventive composition for ballpoint pens according to the present invention uses a urea composition, that is, a urea compound, in order to solve the above problems of the conventional ink backflow preventive compositions for ballpoint pens. By thickening the liquid, it is possible to ensure the properties of the ballpoint pen with excellent ink follow-up properties during writing and ink backflow prevention properties in the upright state.

This ink backflow inhibitor composition for ball-point pens uses mineral oil, synthetic oil, ester oil, silicone oil or low-viscosity polybutene as a base oil of a hardly volatile liquid and has the general formula R'-NHCONH-R- A urea-based grease composition containing 0.5 to 40 mass% of a thickener which is a compound of NHCONH-R 'is used. That is, this ink backflow inhibitor composition for ballpoint pens is mainly composed of
It is characterized in that a urea composition is added as a thickener to a hardly volatile liquid. In this ink backflow inhibitor composition for ball-point pens, the content of the urea composition is in the range of 0.1% by mass to 40% by mass.

In the general formula of the above compound, R is any of a tolylene group, a diphenylmethane group, a ditolylene group and a naphthalene group, and R'is an alkyl group, a cycloalkyl group, an aryl group or a combination thereof. The alkyl group is an octyl group, a dodecyl group,
It is a hexadecyl group or an octadecyl group, the cycloalkyl group is a cyclohexyl group, an ethylcyclohexyl group or a dicyclohexyl group, and the aryl group is a phenyl group, a diphenyl group, an ethylphenyl group or an ethoxyphenyl group.

The content of the urea compound used in the composition for preventing backflow of ink for the ballpoint pen is 0.1% by mass to 4% by mass.
Although it was 0% by mass, it was confirmed that if it was 0.1% by mass or less, it was too soft and no effect was obtained, and if it was 40% by mass or more, it was too hard to be practical. The urea compound used in the ink backflow preventive composition for ballpoint pens may be used alone or in combination with other thickeners, but in consideration of the effect on ink, it is mixed with other thickeners. It was found to be desirable to use

Other thickeners include hydrophilic silica,
Hydrophobic silica, eg Aerosil 200, R972
It is used in combination with fine particle silica such as R974D and R976D, fine particle silica subjected to methylation treatment, or water-insoluble metal soap such as aluminum stearate soap and lithium stearate soap. The addition amount of these is preferably 0.1% by mass to 15% by mass with respect to the total amount of the ink follower.

The base oil used in the ink backflow preventive composition for ballpoint pens is not limited as long as it has a usable kinematic viscosity, but in the case of silicone oil, the kinematic viscosity at 25 ° C. Is 100 to 100,000 mm ² /
In the case of mineral oil, synthetic oil, ester oil and polybutene oil, the kinematic viscosity at 40 ° C is 100 to
It has been found that a range of 10000 mm ² / s is desirable. In the case of silicone oil, the kinematic viscosity at 25 ° C is 10
If it is 0 mm ² / s or less, the followability is too good, and the ink discharge amount is too large, which is not suitable for practical use. Also, if the kinematic viscosity at 25 ° C is 100,000 mm ² / s or more, the ink discharge is too great. It became clear that the amount was small and the writing with a ball-point pen became difficult, making it impractical. Similarly, in the case of mineral oil, synthetic oil, ester oil and polybutene oil, the kinematic viscosity at 40 ° C is 100 mm ²
If the kinematic viscosity at 40 ° C. is 10000 mm ² / s or more, the ink discharge amount becomes small if the kinematic viscosity is 40 ° C. or less. , It became clear that it became impossible to write with a ballpoint pen, which was not practical.

In order to test the high temperature performance, the followability, the impact resistance and the mixing resistance of the ink backflow inhibitor compositions for ball-point pens of Examples and Comparative Examples, commercially available ball-point pens A and commercially available ball-point pens B shown in Table 4 were tested. And a commercially available ballpoint pen C (hereinafter referred to as ballpoint pen A, ballpoint pen B and ballpoint pen C) were purchased. The ink backflow preventive composition filled in the ball-point pens A, B and C was absorbed with a syringe, and the ink backflow preventive composition adhering to the wall surface of the ink cylinder was wiped off. The compositions of Example 18 and Comparative Examples 1 to 10 were filled. For ballpoint pen A, the inner diameter of the ink cylinder is 1.0 mm,
The filling amount of the ink backflow prevention composition for ballpoint pens is 4 mm.
^{Is 3} . Regarding the ball-point pen B, the inner diameter of the ink cylinder is 2.5 mm, and the filling amount of the ink backflow preventing composition for ball-point pens is 60 mm ³ . Also, a ballpoint pen C
The inner diameter of the ink cylinder is 3.5 mm, and the filling amount of the ink backflow prevention composition for ballpoint pens is 120 m.
m is ^3.

[Table 4]

At this time, Examples 1 to 18 are the same as the amounts of the compositions shown in Tables 1 and 2, and Comparative Examples 1 to 1
In No. 0, only the amount of the composition shown in Table 3 was continuously filled with the ink at the ink end portion, that is, the end surface of the ink, and the following four evaluation tests were performed. The composition of the ink backflow inhibitor composition for ball-point pens shown in Examples 1 to 18 according to the present invention is a composition in which a urea composition is added as a thickener to a hardly volatile liquid of a base oil. . In addition, the composition of the ink backflow inhibitor composition for ball-point pens shown in Comparative Examples 1 to 10 does not include the urea-based thickener composition.

(1) As a high temperature performance test of the ball-point pens A, B and C, the ball-point pens A, B and C were left standing in an 80 ° C. constant temperature air bath for 30 days, and then the appearance of the ball-point pens was observed. . By observing the appearance of the ball-point pens A, B and C, the ball-point pens in which the ink backflow preventive composition flows in the ink cylinder or flows out from the ink cylinder and the separation of the base oil and the gelling agent is observed. It was rejected. (2) As a follow-up test of the ballpoint pens A, B and C, the ballpoint pens A, B and C continuously write at a speed of 10 cm / sec until the ink runs out, and the ink backflow preventive composition consumes the ink. It was observed whether or not to follow. A part of the ink backflow preventive composition adheres to the wall surface of the ink cylinder and ink remains at the end of the ink cylinder, and the ink backflow preventer composition does not move in the ink cylinder, and A ballpoint pen that became unreadable on the way was rejected. (3) As an impact resistance test of ballpoint pens A, B and C,
The ball-point pens A, B, and C were held with the ball-point tips up and dropped from the height of lm to the concrete floor 50 times, and then the appearance of the ball-point pens A, B, and C was observed.
A ballpoint pen in which the ink backflow preventive composition flowed in the ink cylinder or a ballpoint pen in which the ink flowed out from the ink cylinder was judged to be unacceptable. (4) As a mixing resistance test of ballpoint pens A, B and C,
After leaving the ballpoint pens of the ballpoint pens A, B and C facing upward in a constant temperature air bath at 80 ° C. for 30 days, the appearance of the ballpoint pens A, B and C was observed. A ballpoint pen in which the ink backflow preventive composition was mixed with the ink was rejected.

Regarding the ball-point pens A, B and C filled with the ink backflow preventive composition for ball-point pens shown in Examples 1 to 18, the above-mentioned high temperature performance test, follow-up test, impact resistance test and mixing resistance test were conducted. The evaluation test results are shown in Tables 1 and 2. Further, the ballpoint pens A, B and C filled with the ink backflow preventive composition for ballpoint pens shown in Comparative Examples 1 to 10 were subjected to the above high temperature performance test, follow-up test, impact resistance test and mixing resistance test. Table 3 shows the evaluation test results. As is clear from the evaluation test results of these Examples and Comparative Examples, the ink backflow preventive composition for ballpoint pens of the present invention has excellent high-temperature performance, followability, impact resistance and mixing resistance. I understand.

[Table 1]

[Table 2]

[Table 3]

In Examples 1 to 18 and Comparative Examples 1 to 10 according to the present invention, samples of ink backflow preventive compositions for ballpoint pens were prepared as follows. For Examples 1 to 18, half of the base oil and diphenylmethane 4,4 ′ diisocyanate were weighed in a container.
Then, the contents in the container were heated to 55 ° C. with stirring to prepare an isocyanate solution. In addition, half of the base oil and amine were weighed in another container. Then, the content in the container was heated to 50 ° C. with stirring to prepare an amine solution.
Next, the amine solution was put into a container containing an isocyanate solution to react them with each other. The contents in the reacted container were heated to 180 ° C. with stirring.
It was cooled to room temperature with stirring and passed through a three-roll mill for adjustment. Silica was added before passing through the three roll mill. In Comparative Examples 1 to 10, the respective raw materials were weighed out, mixed, and passed through a three-roll mill at room temperature for adjustment.

[0024]

The ink backflow inhibitor composition for ball-point pens according to the present invention is prepared or produced by adding the urea composition as a thickener to the hardly volatile liquid as described above, and therefore has high temperature performance. It has excellent followability, impact resistance, and mixing resistance, and is highly practical as a ballpoint pen.
That is, in the ballpoint pen filled with the ink backflow preventive composition for a ballpoint pen, even if the tip of the ballpoint pen is left in an upward direction, a horizontal direction, or the like, the ink leaks from the ink cylinder portion without flowing back through the ink cylinder portion. Even if a shock is applied to the ink cylinder, the ink does not leak and scatter from the ink cylinder, and there is no risk of soiling clothes, the surrounding environment, etc., and the ink cylinder is filled. There is no risk that the ink that has been applied will evaporate through the open side.

Continued front page    F-term (reference) 2C350 GA03 KF03 NA10 NA11 NC06                       NC20

Claims (6)

[Claims] 1. An ink backflow preventive composition for a ballpoint pen, wherein a urea composition is added as a thickening agent to a hardly volatile liquid. 2. The content of the urea composition is 0.1
The ink backflow inhibitor composition for ball-point pens according to claim 1, wherein the composition is in the range of from 40% by mass to 40% by mass. 3. The urea-based composition as the thickener has a general formula of R′—NHCONH—R—NHCON.
The ink backflow inhibitor composition for a ball-point pen according to claim 1 or 2, which is a compound of HR '. (In the above general formula, R is a divalent hydrocarbon compound having 2 to 20 carbon atoms and its derivative, and R'is 1 to 20.
And monovalent hydrocarbon compounds and their derivatives. ) 4. In the general formula of the compound, R is a tolylene group, a diphenylmethane group, a ditolylene group or a naphthalene group, R'is an alkyl group, a cycloalkyl group, an aryl group or a combination thereof, and an alkyl group is an octyl group or dodecyl. Group, hexadecyl group or octadecyl group,
The ink backflow preventing agent for a ball-point pen according to claim 3, wherein the cycloalkyl group is a cyclohexyl group, an ethylcyclohexyl group or a dicyclohexyl group, and the aryl group is a phenyl group, a diphenyl group, an ethylphenyl group or an ethoxyphenyl group. Composition. 5. The refractory liquid is 100 to 100 at 25 ° C.
Silicone oil having a kinematic viscosity 100,000 mm ² / s, refined mineral oil having a kinematic viscosity of 100~10000mm ² / s at 40 ° C., claims, characterized in that the synthetic oil is any one or more of polybutene oil The ink backflow inhibitor composition for a ballpoint pen according to any one of 1 to 4. 6. The ink backflow preventive composition for a ballpoint pen according to claim 1, wherein a 1-minute value measured by a spread meter at 25 ° C. is 20 to 50 mm.