JP2002254882A - Pen refill for writing utensil and writing utensil using the pen refill - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pen refill for a writing utensil which is safe and does not take time and further, is less costly with a beautiful appearance, with regard to the modification of the wettability of ink of the pen refill for a writing utensil as well as a writing utensil using this pen refill. SOLUTION: This pen refill for a writing utensil is formed of a thermoplastic resin containing a resin with an N-phenylmaleimide structure in a copolymer skeleton as a material for the pen refill. Also the writing utensil using this pen refill is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pen core for a writing instrument for adjusting a pressure change in an ink tank provided between a writing tip and an ink tank, and a writing instrument using the same. More specifically, the present invention relates to a pen core material for a writing instrument which facilitates the modification of the wettability of the surface thereof, and a writing instrument using the same.

[0002]

2. Description of the Related Art A pen core for a writing instrument (hereinafter abbreviated as a pen core) directly fills an ink tank with ink without using an ink occluding material such as a writing tip or a batting which enables writing by utilizing a capillary phenomenon. It is mounted between a writing tip (pen tip) of a writing instrument such as a fountain pen and an ink tank, and is mainly used for adjusting a pressure change in the ink tank. That is, the pen core has a pressure adjusting unit such as a so-called comb groove structure, and when the air in the ink tank expands due to a change in the outside air pressure or a rise in temperature, the ink pushed out from the ink tank is discharged. It has a function of temporarily holding the ink so that it does not drop from the writing tip or the air replacement hole.

[0003] Further, at least one groove is formed from the rear end of the pen core to the portion in contact with the writing tip so that the capillary force acts, and a function of guiding the ink in the ink tank to the writing tip through the groove is provided. Have. Therefore, this is an essential configuration in a writing implement that directly fills a low-viscosity ink into a writing tip and an ink tank that enable writing by utilizing the capillary phenomenon.

[0004] In terms of the function of the pen core as described above, the wettability of the ink on the surface of the pen core is important. If the wettability is insufficient, the ink guided from the inside of the ink tank will be guided by the guide grooves of the pen core. The ink cannot be sent to the writing tip due to the capillary force of the guide groove not working well, the ink holding force with the pen core is weak, Ink may be blown out due to a rise in temperature or the like.

Conventionally, pen resins are made of AS resin (acrylonitrile / styrene copolymer) or ABS resin (acrylonitrile / butadiene / styrene copolymer) in consideration of moldability, mechanical strength and dimensional stability. Use of such is common. However, AS resin and ABS resin have poor wettability to ink in the surface state as it is after molding, and in order to improve wettability and exhibit good pen core performance, a strong acid such as a chromic acid mixed solution or sodium hydroxide is required. It has been usual to immerse in a strong alkaline solution such as a solution for a certain period of time to perform a chemical hydrophilization treatment to form a hydrophilic group on the surface.

[0006] However, the chemical processing solution is often an unfavorable processing solution in terms of environmental measures, and there is also a danger in operation. The liquid may react with the ink and cause a fatal defect in the performance as a writing instrument. In addition, not only the cost is increased due to the processing step, but also the maintenance of the wettability of the treated surface is deteriorated with time. Further, since the chemical treatment is an etching step, the appearance is often impaired, and it has been difficult to obtain a pen core with a beautiful appearance.

In addition to the above, the surface area of a polysiloxane layer having a silanol group is formed on the surface with a specific thickness, or the total area of the etching recesses with respect to the entire surface of the etching portion is specified. Surfactant is distributed, there are such as those in which alumina and / or silica fine particles are uniformly dispersed and attached to the entire surface at a specific average interval on the ink contact surface, but all of them change with time, There were problems such as the appearance was not beautiful.

In some cases, the pen core material is not chemically treated, but is subjected to low-temperature plasma treatment to perform mechanical surface modification. However, the effect is lost over time. In addition, it is practically difficult to uniformly perform plasma treatment on the entire surface of a complicated and complicated pen core, and if processing unevenness occurs due to fine ink guide grooves or the like, a problem occurs in the pen core performance itself. So it was not enough.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to improve the wettability and the like of ink of a pen core, and has a beautiful appearance which is safe, takes less time and does not cost much. An object of the present invention is to provide a pen core for a writing implement and a writing implement using the same.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention uses a pen core for a writing implement according to the present invention by using a specific resin as a material for the pen core for a writing implement. The writing implement was completed. That is, the present invention relates to a pen core for a writing implement provided between a writing tip and an ink tank for guiding ink and adjusting a pressure change in the ink tank. 1. A pen core for a writing instrument, wherein the core is made of a thermoplastic resin containing a resin having an N-phenylmaleimide structure in a copolymer skeleton 2. The thermoplastic resin, wherein the pen core for a writing instrument contains a styrene-N-phenylmaleimide copolymer 2. The pen core for writing implements described in item 1 made of resin 3. The pen core for writing implements described in any one of items 1 or 2 made of a thermoplastic resin having the following general formula structure: Pen lead.

Embedded image 4. 4. The pen core for a writing implement according to any one of the first to third aspects, wherein the pen core for a writing implement comprises a composite material obtained by kneading and mixing two or more resins. 5. The pen core for a writing implement according to any one of claims 1 to 4, wherein the pen core for a writing implement further comprises a composite material containing an ABS (acrylonitrile-butadiene-styrene) resin. 6. Item 6. A pen core for a writing implement, wherein the surface of the pen core for a writing implement according to any one of Items 1 to 5 is subjected to a hydrophilic coating treatment. 7. A writing implement with a pen core for guiding ink between a writing tip that enables writing using the capillary phenomenon and an ink tank filled with low-viscosity aqueous ink, and adjusting pressure changes in the ink tank 7. A writing implement, wherein the pen core comprises the pen core for a writing implement according to any one of Items 1 to 6. ".

A specific example of a pen core for a writing instrument for adjusting a pressure change in the ink tank provided between the writing tip and the ink tank includes a comb groove-shaped one as shown in the drawings. However, the present invention may be applied to an ink relay core formed by resin extrusion or a resin nib integrated with the nib.

Referring to the writing implement shown in FIG. 1, the writing implement is a so-called fountain pen using a nib formed of a thin metal plate. As shown in FIG. 1, a pen tip 1 used for a fountain pen is press-fitted into a distal end portion of a neck 3 while being arranged on a peripheral surface of a distal end portion of a pen core 2. Pen tip 1
A slit 1a is formed from the center of the pen tip 1 to the tip 1b. The pen core 2 has an ink groove 2 a formed on the peripheral surface facing the pen tip 1, and the ink groove 2 a extends to the end of the pen core 2. The ink groove 2 a is communicated with the inside of the ink tank 4, and the ink tank 4 is detachably fitted into the end of the neck tube 3.

Therefore, the ink in the ink tank 4 is guided to the cut groove 1a of the pen point 1 through the ink groove 2a. Then, the ink guided to the cutting groove 1a of the pen tip 1 is guided to the tip 1b via the cutting groove 1a. As a result, it is possible to write a character or the like by bringing the tip 1b of the pen tip 1 into contact with paper or the like.

On the other hand, as shown in FIG. 2, an air groove 2b and a collector space 2c as a pressure adjusting portion are formed in the pen core 2, and the air groove 2b communicates with the ink tank 4. Further, as shown in FIG. 3, the air groove 2b communicates with the air escape groove 2e via the communication groove 2d, and when the ink in the ink tank 4 is guided to the pen tip 1 and consumed, the amount of consumed ink is reduced. An appropriate amount of air is supplied into the ink tank 4 as bubbles through the air escape groove 2e, the communication groove 2d, and the air groove 2b. As described above, the amount of air corresponding to the amount of ink consumed in the ink tank 4 is supplied into the ink tank 4, so that the ink in the ink tank 4 is sufficiently supplied to the pen tip 1.

The collector space 2c communicates with the inside of the ink tank 4 via the ink groove 2a. The collector space 2c has a function of storing ink overflowing from the ink tank 4 due to air expansion in the ink tank 4 due to a change in ambient pressure or a rise in temperature.

The pen core of the present invention is a pen core for a writing implement for adjusting a pressure change in an ink tank provided between a writing tip and an ink tank, and has an N-phenylmaleimide structure as a resin material. It is characterized by containing a resin having a polymer skeleton. If an N-phenylmaleimide structure is provided in the copolymer skeleton, copolymerization with other structures is possible. However, if a styrene-N-phenylmaleimide copolymer copolymerized with styrene is used as a composite material, the styrene moiety Is preferred because it increases the compatibility with other resins to be kneaded and mixed. Above all, the compatibility with the ABS resin is improved, so that it is particularly preferable. For example, there is one made of a thermoplastic resin having a structure represented by the following general formula.

Embedded image

The pen core of the present invention contains the above-mentioned specific resin. The resin has an N-phenylmaleimide structure in the copolymer skeleton, whereby the properties of the resin surface are improved, and the ink used and further processed. The wettability of the hydrophilic coating solution is improved. Specifically, it is estimated that the wettability of water is improved by the polarity of the coordinated C ＝ O bond.

Although the pen core formed from the above-mentioned material can be used basically only by degreasing, it is more preferable to apply a hydrophilic coat in order to further exert the above-mentioned pen core performance.

Usually, a pen core is often manufactured by an injection molding method. At this time, a release agent is applied to the surface of an injection mold used to separate the pen core from the mold. Making it easier. Therefore, on the surface of the injected pen core, there is a release agent typified by a silicon-based substance adhered from the mold. It is necessary to remove the agent to exhibit the inherent hydrophilicity of the pen core or to facilitate the hydrophilic coating treatment.

The size and shape of the pen core are not one type but a plurality of types, and the required pen core performance generally has a wide range. Depending on the required pen core performance, the performance may not be sufficiently achieved only by the hydrophilicity of the resin itself. Therefore, the hydrophilicity of the pen core surface can be further increased by the hydrophilic coating treatment to improve the performance. For the hydrophilic coating treatment, an aqueous solution of a water-soluble resin or an aqueous solution of a surfactant can be used.

The pen core may be subjected to a physical surface treatment such as sandblasting before and after various treatments. Sandblasting is very effective because physical treatment can be used together without changing the chemical composition of the resin surface.

Specific examples of the resin having an N-phenylmaleimide structure in the copolymer skeleton include those copolymerized with styrene and those described in the above chemical formula.
The resin is often used in a state of being kneaded and mixed with another resin. For example, a mixture obtained by kneading and mixing with an ABS resin may be used. Commercial products include Marekka brand K series of Denki Kagaku Kogyo Co., Ltd., K-090, K-095, K-10
0, K-200, K-300, K-043, K-400, K-510, K-600, K-700
There is a lineup such as. Such a composite material can have multiple functions, and the ABS structure can
The surface wettability can be improved by the styrene-N-phenylmaleimide resin while maintaining the performance of the BS resin (good moldability, high durability, dimensional stability). A
BS resin is particularly useful as a pen core material, but ABS resin
If a resin having another basic skeleton is used instead of the resin, it is possible to obtain a pen core material having the same properties as the resin having the skeleton.

When the copolymer having an N-phenylmaleimide structure and another resin are kneaded and mixed, the properties can be appropriately set only by adjusting the properties to desired physical properties. For example,
When kneading and mixing the styrene-N phenylmaleimide resin and the ABS resin, the ratio of the former to the latter is 10:90 to 3
When the ratio is about 0:70, physical properties preferable as a pen core material are obtained.

In the present invention, the term "copolymer" or "resin" has a broad meaning, and includes copolymers and polymer alloys containing other components. However, if the composition includes other components, its properties may be affected. Therefore, a narrow definition containing no other components is preferable.

The pen tip and the writing instrument which can be used in the present invention include a fountain pen, a plate pen, a ball-point pen, a felt pen, and the like. Any type that uses the capillary force of a pen core can be used as appropriate.

Next, the components that can be used in the ink of the present invention will be described. Inks that can be used in the writing instrument of the present invention include water-based inks, and those containing water as a basic solvent, a humectant, a coloring agent, a resin component, etc. And the like are appropriately used. Although it is possible to use oil-based ink, a remarkable effect cannot be expected as compared with the case of using water-based ink.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION

EXAMPLES The present invention will be specifically described below with reference to examples.

Examples 1 to 4 and Comparative Examples 1 to 3 As shown in Table 1, the pen cores of Examples and Comparative Examples were prepared by subjecting each resin and, if necessary, to surface treatment. Various evaluations were made with black ink. The writing instrument used for the evaluation was a desk pen manufactured by Pilot Corporation, and the ink used was an ink having a viscosity of 1.5 mPa · S, a pH of 9.4, and a surface tension of 50.5 mN / m.

[0029]

[Table 1]

Each performance evaluation was performed as follows. (Average value of n = 10) <Hydrophilic coat applicability>: It was visually evaluated whether or not the hydrophilic coat could be made uniform. <Ink groove suction test>: After immersing the rear part of the pen core in a petri dish in which black ink was poured at a height of 2 to 3 mm, the time required for the ink to suck up to 2 mm from the tip was measured. <Initial ink ejection property>: After attaching the pen core to a desk pen to obtain a completed product, insert the black ink spare with the pen tip upward. Next, after the pen tip was turned downward, the time until the ink reached the blotting paper was measured by lightly touching the blotting paper. <Bottle drop test>: After attaching the pen core to the desk pen to make the finished product, insert the black ink spare with the pen tip facing upward. Next, the pen tip is turned down so that the ink reaches the pen tip so that writing is possible. After the completed pen was set downward on the closed fountain tester, when the pressure was reduced at a reduced pressure of 1.4 kPa / min, the time until ink bleeding was measured.

[0031]

As described above, the pen core material for a writing instrument and the writing instrument using the same according to the present invention can adjust the pressure change in the ink tank provided between the writing tip and the ink tank. It is possible to improve the wettability of its surface without using environmentally unfavorable chemical treatments, etc. and to obtain a pen core with a beautiful appearance because it does not perform physical surface modification such as etching treatment or plasma treatment. It is possible,
It has excellent effects.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a tip of a writing instrument of the present invention in a longitudinal sectional state.

FIG. 2 is a plan view showing a pen core and a pen tip of a writing instrument of the present invention when viewed from a plane direction.

FIG. 3 is a side view showing the pen core and the pen tip of the writing instrument of the present invention viewed from the side.

FIG. 4 is an AA cross-sectional view showing a vertical cross section taken along line AA in FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pen tip 2 Pen core 3 Neck tube 4 Ink tank 5 Neck tube 6 Slit

Claims (7)

[Claims] 1. A pen core for a writing implement provided between a writing tip and an ink tank for guiding ink and adjusting a pressure change in the ink tank, wherein the pen core for the writing implement is N-phenyl. A pen core for a writing implement, comprising a thermoplastic resin containing a resin having a maleimide structure in a copolymer skeleton. 2. The pen core for a writing instrument according to claim 1, wherein the pen core for a writing instrument is made of a thermoplastic resin containing a styrene-N-phenylmaleimide copolymer. 3. The pen core for a writing instrument according to claim 1, wherein the pen core for a writing instrument is made of a thermoplastic resin having the following general formula structure. Embedded image 4. The pen core for a writing instrument according to claim 1, wherein the pen core for a writing instrument is made of a composite material obtained by kneading and mixing two or more resins. 5. The pen core for a writing instrument according to claim 1, wherein the pen core for a writing instrument is made of a composite material further containing an ABS (acrylonitrile-butadiene-styrene) resin. 6. A pen core for a writing instrument, wherein the surface of the pen core for a writing instrument according to claim 1 is subjected to a hydrophilic coating treatment. 7. A pen for guiding ink between a writing tip enabling writing by utilizing a capillary phenomenon and an ink tank filled with a low-viscosity aqueous ink, and adjusting a pressure change in the ink tank. A writing instrument comprising a core, wherein the pen core comprises the pen core for a writing instrument according to any one of claims 1 to 6.