JPH06247092A - Nib - Google Patents

Abstract

PURPOSE:To prevent a highly hard thin film layer from being cracked and make writing possible for a long distance by a method wherein, in a pipe-shaped nib having a very hard thin film layer formed at least at a writing part, metal is segregated in crystal grain boundaries of the layer. CONSTITUTION:A very hard thin film layer of titanium carbide and tungsten carbide is formed on a writing face of a base material of a pipe-shaped nib made of metal such as stainless steel by a physical vapor deposition method such as a reactive sputtering process. Metals (e.g. Ti, W) are segregated in crystal grain boundaries of the very hard thin film layer to prevent the layer from being cracked due to a drop shock at the time of writing. To segregate the metallic components used for the very hard thin film layer, there is such a method that the amount of gas to be introduced is made smaller at the time of forming the thin film layer, and, in the case where metal as a tertiary component is segregated, such a method that the metal as the tertiary component is contained in advance in a target is used. As a result, writing for a long distance becomes possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pen tip, and more particularly to a pen tip used in a needle pen type writing instrument.

[0002]

2. Description of the Related Art A needle pen type writing instrument is characterized in that the writing line width is always constant, and is used for drawing which requires high accuracy of the writing line width, drawing by output from a computer and the like. Furthermore, with the recent use of computers, it is being put to practical use in the field of art graphs.

As described above, as the field of use of the stylus pen type writing instrument expands, the types of sheets used also increase. For example, in the field of art graphs, recycled paper and films obtained by coating a mixture of calcium carbonate and silica on the surface of a plastic material are also used.

By the way, when writing is performed on the above film with a writing instrument having a pen tip made of metal such as stainless steel, the pen tip is damaged by friction with the film and a long distance cannot be written. . Therefore, in order to obtain a pen tip that can prevent breakage, that is, have good wear resistance and can write over a long distance, ceramics such as alumina are attracting attention, and the pen tip is used as a film-only needle pen type writing instrument. A nib formed of ceramics such as alumina has been proposed. Further, a nib in which a high-hardness thin film layer is formed on the tip of a metal nib base material is also proposed.

[0005]

SUMMARY OF THE INVENTION It is to prevent the needle-shaped pen tip from being damaged during writing. The nib formed of ceramics such as alumina has a problem that the nib is broken due to a load during writing and a drop impact during handling. This is because a needle pen type writing instrument is often required to have a thin handwriting width, and the size of the pen tip is regulated depending on the writing line width. For example, a pen tip with a writing line width of 0.5 mm uses a pipe with an inner diameter of 0.25 mm, an outer diameter of 0.45 mm, and a length of 3 mm. Is extremely difficult to prevent.

Therefore, it is preferable to use a metal such as stainless steel having a high hardness thin film formed at its tip as the pen tip base material. However, in the case of a nib having a high-hardness thin film layer formed on the tip of a metal nib base material, the high-hardness thin film layer is formed by a load during writing or a drop impact during handling, as in the case of the nib formed by the ceramics. There was a problem that the loss of

[0007]

DISCLOSURE OF THE INVENTION The present invention is a pipe-type pen nib having a high-hardness thin film layer formed on at least a writing part, wherein the high-hardness thin film has metal segregated at grain boundaries. The nib is the main point.

The base material of the pen tip of the present invention is a metal pipe, and stainless steel or nickel silver can be used.

The high-hardness thin film layer formed on at least the writing portion of the pen tip is formed to improve the abrasion resistance of the pen tip and enable writing over a long distance. A high hardness thin film layer made of tungsten, chromium nitride, aluminum nitride or the like is preferable.

The high hardness thin film layer can be formed by a physical vapor deposition method such as a reactive sputtering method or an ion plating method.

In the high hardness thin film layer, it is necessary that the metal segregates at the crystal grain boundaries. This is to prevent damage to the high-hardness thin film layer due to a load during writing and a drop impact during handling. Examples of the metal include titanium, tungsten, nickel, iron, chromium, cobalt and the like.

In order to segregate the metal at the grain boundaries, for example, in the case of segregating the metal component used in the high hardness thin film layer, there is a method of reducing the amount of introduced gas at the time of forming the thin film layer. In the case of segregating the metal as the third component, it is possible to adopt a method of including the metal as the third component in the target.

[0013]

In the nib according to the present invention, since the metal layer is segregated at the crystal grain boundaries in the high hardness thin film layer, the metal exists between the crystal grains and prevents the separation of the crystal grains from each other. It is presumed that the high hardness thin film layer can be prevented from being damaged due to the load during writing and the drop impact during handling.

[0014]

【Example】

(Pen tip manufacturing method) Pen tip base material: Material: Stainless steel (SUS304) Shape: Inner diameter 0.25 mm, outer diameter 0.45 mm, length 3 m
m pipe High hardness thin film molding: Equipment; Parallel plate magnetron sputtering equipment Introduced gas; Methane, Argon Applied voltage; 500V

Production Examples 1 to 5 Titanium having a purity of 99% was used as a target, and a titanium carbide thin film as a high hardness thin film was formed on the writing portion of the pen tip. At this time, the pen tip was obtained with an introduced amount of argon of 12 SCCM and an introduced amount of methane of 5, 7, 8, 9, and 11 SCCM, respectively.

Production Example 6 Titanium containing about 5% by weight of nickel was used as a target, and a thin film layer of titanium carbide was formed as a high hardness thin film layer on the writing portion of the pen tip. At this time, the amount of introduced argon is 8
An SCCM was used, and the amount of methane introduced was 8 SCCM to obtain a pen tip.

Production Examples 7 to 11 Tungsten having a purity of 99% was used as a target.
A tungsten carbide thin film layer was formed as a high hardness thin film layer on the writing portion of the pen tip. At this time, the amount of argon introduced is 12 S
CCM, the amount of methane introduced is 2, 4, 6, 8, 1 respectively
The pen tip was obtained as 0 SCCM.

The compositions of the high hardness thin film layers of the nibs obtained in the above Production Examples 1 to 11 were examined by fluorescent X-ray analysis. Further, the pen tip was replaced with a commercially available plotter pen (CPV035, manufactured by Pentel Co., Ltd.) to prepare a needle pen type writing instrument, and a film (9280-0633, coated with a mixture of calcium carbonate and silica,
WREED-PACKER, USA) with a writing load of 70
Writing was performed under the conditions of g, writing angle of 90 °, and writing speed of 30 cm / sec, and the writing distance was measured until the high hardness thin film was worn and the stainless steel as the pen tip base material was exposed. The results are shown in Tables 1, 2, and 3.

[0019]

[Table 1]

The titanium carbide crystals are present in a composition ratio of 1: 1. Therefore, in the titanium carbide thin films containing a large amount of titanium components like the nibs obtained in Production Examples 1 and 2, excess titanium is segregated at the titanium carbide grain boundaries.

[0021]

[Table 2]

As described above, the titanium carbide crystals are present in a composition ratio of 1: 1. Therefore, nickel is segregated at the titanium carbide grain boundaries.

[0023]

[Table 3]

The crystal components of the high hardness thin films of the nibs obtained in Production Examples 7 to 11 were analyzed by the X-ray diffraction method.
The presence of metallic tungsten could be confirmed in the nib of No. 8 and not in those of Production Examples 9 to 11. Therefore, in the high hardness thin films of the nibs obtained in Production Examples 7 and 8, tungsten is segregated at the tungsten carbide grain boundaries.

[0025]

As described above in detail, in the nib according to the present invention, since the metal of the high hardness thin film is segregated at the grain boundaries, the segregated metal causes embrittlement of the high hardness thin film. Since it prevents the loss of the high hardness thin film, it has an excellent effect that writing can be performed over a long distance.

Claims (1)

[Claims] 1. A pipe-type pen nib having a high-hardness thin film layer formed on at least a writing portion, wherein the high-hardness thin film is one in which a metal is segregated at a grain boundary.