JPS6064852A - Type for typewriter - Google Patents

Abstract

PURPOSE:To improve the printing lifetime by injection molding thermoplastic resin which contains inorganic filler of particular or fibrous state, thereby reducing the weight of a type for a typewriter. CONSTITUTION:Filler is fibrous material such as spherical to particular glass fiber or carbon fiber of silica, silicon carbide or glass. Particle diameter of the spherical or particular shape is preferably 3-20mum, and the shape of the fibrous material has preferably 3-20mum of diameter, 30-50mum or length. Thermoplastic resin employs polycarbonate and polyether sulphone, and the content of the filler in the resin composition is preferably 4-40%(wt.).

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to type 2 type with nolistic printing.

Traditionally, typewriter type has been cast from a zinc-aluminum alloy.

Such metal type type is heavy and has an insufficient printing life of about 50,000 times, and furthermore, productivity cannot be said to be good.

Various attempts have been made to reduce the weight of typewriter type and improve its printing life, and one of these is the use of plastic.

The inventors of the present invention have conducted various studies on the use of plastic types for typewriters, and as a result, they have invented a typeface that satisfies the demands for weight reduction and improved printing life.

The gist of the present invention is a typewriter type made of a thermoplastic resin containing a granular or fibrous inorganic filler and formed by injection molding.

The shape of the inorganic filler may be granular or fibrous, but granular fillers, particularly spherical ones, are preferred.

The reason why spherical inorganic fillers are particularly preferable as typewriter type is considered to be as follows. The interface between the spherical filler and the resin is smooth with no irregularities. Therefore, when the character portion of the typeface is subjected to impact during printing, the impact force is not concentrated on a specific portion on or near the surface of the character portion to the extent that it destroys the resin, but is uniformly dispersed inside.

Specifically, they are spherical or granular materials such as silica, silicon carbide, and glass, and fibrous materials such as glass fibers and carbon fibers.

The particle size of the spherical or granular particles is preferably 3 to 20 μm. If the particle size is smaller than 3 μm, the reinforcing effect will be weak, and if it is larger than 20 μm, the filler will not be filled into the fine parts of the characters, which will significantly reduce the appearance of the type and shapeability of the characters, resulting in poor print quality. It damages the

The current state of the fibrous material is 3 to 20 μm in diameter and 30 to 50 μm in length.
m is preferred. If it is smaller than this range, the reinforcing effect will be weaker, and if it is larger than this range, the fine parts of the printed characters will not be filled with fine details.

Next, as thermoplastic resins, ABSlPVC, polycarbonate/, polyethersulfone, PPS, PPO
However, polycarbonate and polyether sulfone have the best properties for printing type.

Further, the content of the inorganic filler in the resin composition is 5 to 4.
0% (weight %, same hereinafter) is preferable.

The type of the present invention is formed by injection molding using the resin composition.

Next, as an example, a resin composition having the following formulation was injection molded to obtain a printed character "-".

Example 1 Polycarbonate 75-thick glass beads (5-10 μm) 25-thick Example 2 Polyethersulfone 80-thick glass beads (5-1
5 μm) 20 Comparative Example Zn-At Alloy The printing life of these types was measured using an actual small Japanese typewriter (using carbon ribbon, lift-off method), and the results are as follows.

The printing type of the present invention has the following features.

(1) The printing life is significantly superior.

(n) Since it is light in weight, it is easy to handle, and the weight of the type holder can be reduced.

011) Productivity is good because it is manufactured by injection molding.

Patent applicant: Sumitomo Bakelite Co., Ltd. Procedural amendment (voluntary) 226 1981 Date of birth Monthly date ÷ Date of occurrence Dear Commissioner of the Japan Patent Office 1, Indication of the case 1989 Patent Application No. 472139 2, Name of the invention Typewriter type 3 , Relationship to the case of the person making the amendment Patent applicant address: 1-2-2-4 Uchisaiwai-cho, Chiyoda-ku, Tokyo, Specification to be amended: 2゛°pa-゛°, and drawings.

5. Contents of the amendment as per attached sheet
T-zone II Inkei Mugiirsu. . 1 Description 1. Name of the invention Typewriter type 2. Claims A typewriter type made of a thermoplastic resin containing a granular or fibrous inorganic filler and formed by injection molding.

3. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to typewriter type made of plastic, and particularly to typewriter types used in typewriters that select and print one piece at a time.

Figure 1 shows an example of such typeface. Printing of type is performed by applying an impact force (printing force) in the direction of the arrow to the back surface (3) of the type.

Conventionally, typewriter type has been manufactured by casting from a zinc-aluminum alloy.

However, the printed characters used in such typewriters (
11 is often Japanese characters, etc., which have extremely thin line widths, and conventional metal type is heavy, so the printing surface at the tip of the character (2)
The printing force applied to the paper has to be large, and the printing life is 5.
It was a short one, about 10,000 times.

Furthermore, productivity could not be said to be good.

Various efforts have been made to reduce the weight of typewriter type and improve its printing life, and one of these is the use of plastic.

The inventors of the present invention have conducted various studies on the use of plastic typefaces for typewriters, and as a result, they have invented a typeface that satisfies the demands of being lighter and having a longer printing life.

The gist of the present invention is a typewriter type formed by injection molding from a thermoplastic resin containing a granular or fibrous inorganic filler.

The shape of the inorganic filler may be granular or fibrous, but granular fillers, particularly spherical ones, are preferred. The reasons why spherical inorganic fillers are preferable for typewriter type, particularly typewriter type that selects and prints one piece at a time, are considered to be as follows. The interface between the spherical filler and the resin is smooth with no irregularities, so when the character part of the type receives an impact from the printing force during printing, the impact force is so specific that it destroys the resin at or near the character part surface. It is not concentrated in the area but is evenly distributed inside. Therefore, even in the case of characters with extremely narrow line widths, such as Japanese characters, there is very little wear or chipping of the printed characters due to the printing force, and the printing life can be improved.

Specifically, they are spherical or granular materials such as silica, silicon carbide, and glass, and fibrous materials such as glass fibers and carbon fibers.

The particle size of the spherical or granular particles is preferably 3 to 20 μm. If the particle size is smaller than 3 μm, the reinforcing effect will be weak, and if the particle size is larger than 20 μm, the filler will not be filled into the fine parts of the characters, which will significantly reduce the appearance of the type and shapeability of the characters, resulting in poor printing. It is degrading.

The shape of the fibrous material is 3 to 20 μm in diameter and 30 to 50 μm in length.
μm is preferred. If it is smaller than this range, the reinforcing effect will be weak, and if it is larger than this range, the fibers will not be filled into the fine parts of the printed characters.

Next, as thermoplastic resins, there are ABS, PVC, polycarbonate, polyethersulfone, PPS, PPO, etc., but the ones with excellent properties for printing type are those with a content of polycarbonate and polyethersulfone of 5 to 5. 40% (weight i%, same hereinafter) is preferable.

The type of the present invention is formed by injection molding using the resin composition.

Next, as an example, a resin composition having the following formulation was injection molded to obtain a printed character "-".

Example 1 Polycarbonate 75% glass beads (5-10 μm) 25% Example 2 Polyethersulfone 80% glass beads (5-15 μm)
) 20% Comparative Example Zn-k1 Alloy The printing life of these types was measured using an actual small Japanese typewriter (using carbon ribbon, lift-off method), and the results are as follows.

The printing type of the present invention has the following length.

(1) The printing life is significantly superior.

(11) Since it is lightweight, it is easy to handle, and furthermore, the weight of the type holder can be reduced.

Since it is manufactured by Gill injection molding, productivity is high. 4. Brief Description of the Drawings FIG. 1 is a perspective view of an example of typewriter type.

(1) Printed characters (2) Printed surface (3) Back patent applicant Sumitomo Bakelite Co., Ltd.

Claims (1)

[Claims] A typewriter type formed by injection molding from a thermoplastic resin containing a granular or fibrous inorganic filler.