JPH03236999A - Pen point of liquid writing utensil - Google Patents

Abstract

PURPOSE:To enhance writing life to a large extent by improving abrasion resistance and to inexpensively prepare a pen point markedly improved in a writing feeling by stretching a molded body, which is obtained by molding a crystalline polymer, having ink outflow gaps in the axial direction thereof. CONSTITUTION:The filament of a high draw ratio obtained by stretching a molded body having ink outflow gaps obtained by molding a crystalline polymer in high magnification in the axial direction thereof becomes the pen point of a liquid writing utensil excellent in writing characteristics, especially, in abrasion resistance and a writing feeling. The crystalline polymer is a known one and, when a polar group is provided in a molecule, a commercial polyacetal, polyamide or polyester resin can be used but, especially, the polyacetal resin is a material capable of easily generating the rearrangement of a molecular chain by its simple molecular structure and weak bipolar interaction and pref. because of the moldability, abrasion resistance and ink wettability as a pen point.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a nib of a liquid writing instrument having a gap for ink outflow, and more particularly to a nib of a liquid writing instrument having a gap for ink to flow out. The present invention relates to a pen nib for a limb writing instrument which has a very good writing taste.

[Conventional technology]

Conventionally, most pen nibs of this type have been obtained by extrusion processing thermoplastic resin, and the resin used is polyamide, polyurethane, polyacetal, etc. alone, or these resins are mixed with fillers. Composite charges were commonly used.

When writing with the paulownia wood nib, liquid such as ink acts as a lubricant during sliding friction, but it has the disadvantage of relatively large wear and tear, especially for people who write with high pressure. This tendency was noticeable when paper was used for paper with large surface roughness or for paper with large surface roughness. In other words, all of the resins mentioned above have problems with respect to abrasion resistance, which affects the writing life of the pen tip. Therefore, this low abrasion resistance is a major obstacle in designing liquid writing instruments.
In particular, the following two points can be mentioned.

The point is that it is necessary to balance the amount of ink stored in the ink absorber with the amount of wear on the pen tip, but since conventional pen tips have a large amount of wear, it is necessary to have enough ink. However, the lifespan of liquid writing instruments is limited by nib wear.

Another point is that by making the ink absorbing body into a cartridge, the writing life can be greatly extended, but the wear resistance of the conventional pen nib with an irregular cross section and a gap for ink to flow out is low. It is hardly useful to have a liquid writing instrument with a replaceable ink cartridge.

[Problem to be solved by the invention]

By the way, the present inventor has been researching various pen nibs with gaps for ink to flow out, and has found pen nibs with high abrasion resistance,
Although abrasion can be solved by using glass, ceramics, various rod metals, etc., these particles are less likely to affect writing, which is another important characteristic of writing instrument nibs compared to nibs made of plastic materials. The disadvantage is that the taste is very poor, and the writing quality tends to deteriorate especially if you write with a thin line width, and the paper fibers etc. This caused problems such as digging into the diary and disturbing the lines drawn.

Therefore, the present invention has been made in consideration of the above circumstances.
]] The aim is to significantly improve the writing life and abrasion resistance that could not be obtained with conventional methods, and to create a liquid writing nib that has a much better writing quality and is industrially easy to use. The objective is to manufacture and provide the product at low cost using a method that is suitable for use.

[First Step to Solve the Problem] As a result of intensive research to achieve the above object, the present inventor has
Writing properties, especially abrasion resistance and writing feel The present invention was completed with the idea of a pen nib for a writing instrument with excellent physical and physical characteristics.

That is, a molded product of an unstretched crystalline polymer usually contains a mixture of crystalline parts in which molecular chains are properly arranged and amorphous parts in which molecular chains are disordered. This localized area causes a decrease in mechanical strength such as elongation rate.

Therefore, in order to improve mechanical strength, the molecular arrangement of this amorphous part is adjusted and crystallized, and the crystalline part becomes a lamellar crystal with folded molecular chains. It is necessary to unravel the folded branch chains and orient them in one direction.

The crystalline polymer used in the present invention is a known one, and as long as it has a polar group in the molecule, commercially available polyacetal resins, polyamide resins, polyester resins, etc. can be used. In particular, polyacetal resins can be used. Resin is a material in which molecular chain rearrangement can easily occur due to its simple molecular structure and weak bipolar prephasing tL action. preferable.

In order to obtain the desired pen nib of the present invention, it is preferable to use a known extrusion molding machine or injection molding machine that is used for molding ordinary thermoplastic resins. From the viewpoint of production cost, it is preferable to use an extrusion molding machine. In any method, it is desirable that the speed of the melt flow and the melt temperature be sufficiently controlled.

Next, the hollow continuous body obtained by stretch molding is stretched to the right of the ink outflow gap. The temperature of the molded product during stretching must be below 150°C. This is because the melting point of polyacetal resin is close to that of polyacetal resin, and even if it is stretched in a molten state, there is no improvement in strength. Then, a pen nib can be created by cutting the obtained stretched molded product into short lengths and polishing the tip into a pen nib shape.

[For production]

The highly stretched pen nib obtained by the present invention has the following excellent advantages.

(1) Since both the amorphous portion and the crystalline portion are oriented in one direction and have a dense crystal structure, it has excellent abrasion resistance during writing.

(2) The strength of the pen core itself is increased, so even people who use high writing pressure will not damage the pen tip.

(3) Since the structural member of the pen tip is made of plastic, it has excellent writing quality, unlike pen nibs made of glass, ceramics, various metals, etc.

(4) Since ordinary thermoplastic resin molding equipment can be used as is, mass production is possible and the unit price per piece is low.

[Fire example]

Next, the present invention will be explained in more detail based on examples.

In this example, polyacetal resin is used as the crystalline polymer, and if the molecule has a polar group in addition to this,
Polyamide resin, polyester resin, etc. can be used.

In this example, after heating, melting and extrusion molding polyacecool resin, a die having a large number of small holes arranged at the tip is attached to the tip so as to have gaps in the irregular cross section, and then extrusion molding is carried out. This molded product was stretched at a stretching rate of 12 times, and cut into short pieces.1.
A pen nib having a gap with an irregular cross section was obtained. This pen nib was assembled into a writing instrument, and the wear amount of the nib was measured when writing was performed using a mechanical writing tester, and a sensory test was conducted by an experienced evaluator to determine the writing feel. Moreover, the bending elongation rate was measured using the pen tip as it was. The results are shown in Table 1.

Next, an embodiment of a gap of irregular cross section for ink to flow out at the pen tip will be described with reference to FIGS. 1 to 7. The first embodiment shown in Fig. 1 has a pen nib 2 with a radial gap 1 opened radially to the outer surface, and if necessary, a pipe 3 is attached to the outer periphery as shown in Fig. 2. do. In addition, the second embodiment shown in FIG. 3 has a pen nib 2 in which branch-like gaps in the circumferential direction are connected in the middle of a radial gap 1 opened on the outer surface in the radial direction.
It is.

Furthermore, the third embodiment shown in FIG.
As shown in the figure, a pair of symmetrical pen nibs 2 are combined and a pipe 3 is attached to the outer periphery and fixed.

The fourth embodiment shown in FIG. 6 has a fan-shaped gap 1 with a complicated shape that opens toward the center, and as shown in FIG. and fix it.

[Comparative example]

After hot-melt extrusion molding the polyacetal resin, heat-melt extrusion molding the polyacetal resin into a state with gaps in a hole-shaped cross section using a die with a large number of small holes arranged so that the polyacetal resin is fused into a state with gaps in a hole-shaped cross section, Stretching, long cutting, annealing, short cutting, polishing and as necessary (7)
Then, the pen tip is made by subjecting it to surface treatment, etc. This pen tip was assembled into a writing instrument and tested in the same way as in the example. The results are also shown in the table below.

[Test mucilage]

Table 1 is in accordance with J15-6037-1986 marking pen.

〔Effect of the invention〕

As explained above, the pen tip according to the present invention has writing characteristics,
In particular, it has excellent abrasion resistance and writing quality, and as is clear from the test results above, with conventional pen nibs, even though there is still sufficient ink remaining, it becomes impossible to write at short writing distances. This made it possible to write over much longer distances.

(o L. In the wear test, the conditions for the written test using a mechanical writing tester were that only the writing load was 1.00 gf.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of the present invention, FIG. 2 is a cross-sectional view showing another usage form of the first embodiment, and FIG. 3 is a cross-sectional view showing a second embodiment of the present invention. FIG. 4 is a cross-sectional view showing a third embodiment of the present invention, FIG. 5 is a cross-sectional view showing another usage form of the third embodiment, and FIG. 6 is a fourth embodiment of the present invention. 0 FIG. 7 is a cross-sectional view showing another usage form of the fourth embodiment. ]... Gap, 2... Pen tip, 3... Pipe.

Claims (1)

[Claims] A pen nib for a liquid writing instrument, characterized in that it is made by stretching in the axial direction a molded product obtained by molding a crystalline polymer and having a gap for ink to flow out.