JPS5917678B2 - writing instrument nib - Google Patents

Description

[Detailed Description of the Invention] Conventionally, as pen nibs for writing instruments, fiber nibs made by bundling synthetic fibers and processed with resin, or hard or thermoplastic synthetic resin nibs with a plurality of ink outflow capillaries formed in the vertical direction, have been used. , thermoplastic resin powder or thermosetting initial condensation resin powder alone or a mixture of metal powder is pressed in a mold,
A synthetic resin nib that is heated and molded (also known as a sintered nib).

) etc. are known. However, these pen nibs have various drawbacks as follows.

In other words, fiber pen nibs lack abrasion resistance, and when writing for a long period of time, it is not possible to obtain thin characters as at the beginning of writing, but the characters become thicker or the tip of the nib comes apart.

Therefore, when the amount of processed resin is increased in order to improve wear resistance, the flow of ink to the pen tip is obstructed, resulting in problems such as inability to write or smearing depending on the direction in which the pen is intended to be written.

Due to the manufacturing method, synthetic resin pen nibs with multiple ink outflow capillaries formed in the vertical direction can only form ink outflow capillaries in the vertical direction, so if you use shorthand or leave the pen with the nib facing up for a long time, the ink absorber will form. The ink does not flow smoothly from the pen to the nib, resulting in disadvantages such as blurring of written characters and the inability to write.

Among the sintered pen nibs, which are also known as sintered pen nibs, sintered pen nibs made of thermoplastic resin powder adhere to each other simply by softening or melting the surface of the powder particles, so the adhesive strength is weak and brittle. It has drawbacks such as breakage during writing and part of the tip being chipped.

In addition, sintered pen nibs made of thermosetting initial condensation resin powder alone or in combination with metal powder have the disadvantage of being hard, lacking in flexibility, and breaking the paper surface when written.

The present invention provides a writing instrument nib made of synthetic resin that can solve these drawbacks, and is made by molding a methoxymethylated polyamide resin by subjecting it to a condensation reaction in a mold in the presence of a catalyst. It's ahead.

In the pen nib obtained by the present invention, unlike conventional sintered nib made of thermoplastic resin powder, adhesion of the resin powder particles to each other is not only due to softening or melting of the powder particle surface only, but also in the presence of a catalyst. A condensation reaction occurs and cross-linking occurs between molecules, and as the reaction progresses, it hardens and becomes a porous polymer molded body with a three-dimensional structure, so the resulting pen tip is flexible as a whole and can be used for writing. There is no risk of the pen tip breaking or part of the tip chipping off, and it also has the abrasion resistance and flexibility unique to polyamide resin, and by freely adjusting the space ratio inside the nib, it can be used as a shorthand or writing instrument. Even if the pen is left with the nib facing up for a long period of time, there is no risk that the written characters will smear or become impossible to write on, and by selecting the shape of the nib, the writing experience is similar to that of a regular brush. can.

For example, it has excellent effects such as the ability to obtain good handwriting of the bouncing parts of kanji characters.

In carrying out the present invention, the methoxymethylated polyamide resin suitably has a degree of methoxymethylation of, for example, 20 to 35 degrees, and may be used in the form of flakes or granules depending on the purpose.

The catalyst is selected from ordinary catalysts for curing thermosetting synthetic resins, and preferably organic acids or salts of organic acids are used.

When mixing the resin and the catalyst, it is necessary that the two are mixed uniformly, and the catalyst is preferably dissolved in water or an organic solvent and then mixed.

The amount of catalyst is selected depending on the type of catalyst and the degree of methoxytylation of the resin. For example, if the degree of methoxymethylation of the resin is 25 mm and the average particle size is 50 microns (14 mm) 1 to 10 inches is appropriate.

The shape of the mold is arbitrarily selected, such as a pen tip, a circular rod, a square rod, or a plate, depending on the purpose.

The amount of resin filled into the mold is adjusted so that the internal void ratio of the nib is 30 to 70 inches, taking into consideration ink fluidity, ink retention, or flexibility.

The filling method is carried out by applying vibration from outside the mold or applying pressure at appropriate times.

The heating temperature is selected depending on other conditions, but is 70 to 1
Performed within 50°C.

When the resin particles in the mold, which are advantageously selected from the above conditions, are heated, the particles soften or melt to form an adhesive state, causing a rough condensation reaction, causing cross-linking between molecules, and as the reaction progresses. When cured, a porous polymer molded product with a three-dimensional structure is obtained.

In addition, in the present invention, in order to adjust the hardness and flexibility, an appropriate amount of other thermosetting initial condensation resin powder, thermoplastic resin powder, or fibrous powder-like inorganic or organic substance may be further mixed with the above materials and molded. can.

Example 1 20 g of ethyl alcohol and 30 h of water were mixed with 21 citric acid and mixed with Toresin F3, which had an average particle size of 60 microns.
0 (manufactured by Teikoku Kagaku Koshu) was added and mixed well with a stirrer, then separated in a furnace and dried.

A 3 Ct capacity mold with a conical tip is filled with 1.52 of the resin F30 while being vibrated from the outside and sealed, heated at 70° C. for 50 minutes, allowed to cool, and taken out from the mold.

The pen nib obtained in the experiment had an internal void ratio of 53.

Example 2 Water 30'? Dissolve 5 g of tartaric acid and add to this the average particle size of 50 microns (waste) Torezin F30X (manufactured by Teikoku Kagaku Koshu)
50V was added, mixed well with a stirrer, separated, dried at low temperature, and the Toresin F30X was placed in an inner rod mold with a capacity of 5Ct. Fill uniformly with appropriate pressure and seal, 150
After heating at ℃ for 30 minutes, let it cool and remove from the mold to form a pen nib with a sharpened tip.

According to experiments, the internal void ratio of this product was 65%.

Note that the component of Torezin manufactured by Teikoku Kagaku Kogyo Co., Ltd. in Example 1.2 is a methoxymethylated polyamide resin.

In addition, Torezin is a registered trademark of methoxymethylated polyamide resin manufactured by Teikoku Kagaku Kogyo Co., Ltd., 1-F30J, rF30
XJ is a symbol indicating the variety.

Claims (1)

[Claims] 1. A writing instrument nib formed by subjecting a methoxymethylated polyamide resin to a condensation reaction in a mold in the presence of a suitable catalyst.