JPS63205260A - Platen roller - Google Patents

Abstract

PURPOSE:To enhance hammer energy efficiency and the durability of a printing element, by mounting a rubber material having specific hardness and a specific impact resilience value to the periphery of a core material. CONSTITUTION:A platen roller is constituted by mounting a rubber material 8 having hardness and an impact resilience value to the periphery of a core material 7. The core material 7 pref. has rigidity and hardness sufficient to obtain impact force necessary for obtaining good printing capacity. The rubber material 8 must have hardness of 95+ or -3 JIS A at 20-25 deg.C based on JIS K6301 and an impact resilience value of 4-7% at 20-30 deg.C based on JIS K6301 and can be obtained by appropriately adjusting the compounding amounts of a raw material polymer, carbon, an inorg. filler, oil, sulfur, a vulcanizing agent, a vulcanization accelerator or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a platen roller, and more particularly to a platen roller used in a printing device such as a typewriter.

[Conventional technology]

Conventionally, printing devices such as typewriters have included a platen roller that acts as a base plate during printing.

This platen roller is generally cylindrical in shape, with a rubber material 2 wrapped around a core material 1, as shown in FIG. When printing, for example, as shown in FIG. By hitting the element with a printing hammer 6, it is pressed against the rubber material 2, and the character of the printing element is printed on the printing paper 3.

The printing performance on the printing paper obtained as described above is determined by the hammer energy of the printing device and the hardness of the rubber material that makes up the platen roller.If the hammer energy is constant, the higher the hardness of the rubber material, the better the printing performance. gets better. Therefore, if the hardness of the rubber material is insufficient for the hammer energy of the printing device used, printing defects such as missing parts of characters or unclear outlines of characters will occur.

In order to prevent such printing defects, attention has been focused on how to increase the hardness of the rubber material used in conventional platen rollers. As a means of achieving high hardness, the rubber composition is usually made by using at least 20 prh or more of an organic reinforcing agent such as modified melamine resin, heystyrene resin, or phenol resin based on 100 parts of the polymer, or Carbon black, especially FEF carbon level or FE
The proportion of carbon black with a diameter finer than F is 50
% or more, high hardness was achieved.

However, although the vulcanized rubber thus obtained can achieve high hardness, it usually has a high impact resilience value. For this reason, when such a rubber material is used for the platen roller, the rebound of the hammer is large, which means that out of the energy given by the hammer, the energy consumed for printing is small.In other words, the energy efficiency of the hammer is poor. turn into. Therefore, in order to perform good printing, it is necessary to increase the hammer energy to compensate for the inefficiency. For this reason, the impact load upon impact increases, leading to progressive wear of the printing element and crushing of printed characters.

Conventionally, this problem has been addressed by improving the durability of the printing element. For example, if it is Dizzy foil,
This was countered by using expensive phenolic resin for the type parts that were prone to crushing, and using wear-resistant polyamide etc. for the support parts that supported the type, using so-called two-color molding, but the durability was poor. There was naturally a limit to the improvement of this technology, and there were also problems in terms of economic efficiency.

[Problem that the invention seeks to solve]

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a platen roller with reduced rebound resilience, which provides good printing performance and excellent type durability.

[Means for solving problems]

The above objects of the present invention are achieved by the present invention as follows.

20~25℃ based on JIS K6301 around the core material
hardness is 95±3 JISA, and JIS
A platen roller equipped with a rubber material having a rebound resilience value of 4 to 7% at 20 to 30°C based on K6301.

[For production]

The platen roller of the present invention has a hardness of 95±3 JISA at 20 to 25°C based on JIS K6301, which is comparable to the rubber material used for general platen rollers, and a rebound resilience value at 20 to 30°C based on JIS K6301. It has a smaller rubber material of 4 to 7% than conventional platen rollers, making it possible to reduce hammer rebound during printing and improve hammer energy efficiency compared to conventional platen rollers. For this reason, it is possible to perform good printing with less hammer energy than before, and furthermore, the impact load when pressing the hammer can be reduced by the amount of energy that is reduced, making it possible to print on Daisy-Foil, etc. It is also possible to improve the durability of the element. Furthermore, with this improvement in durability, it is now possible to use printing elements that were previously inferior in terms of durability, such as the aforementioned Dage foil made by one-color molding of resin such as polyamide, without any particular problems. can. Furthermore, since hammer energy can be reduced, vibrations and noise generated during printing can also be reduced. Furthermore, by reducing the impact resilience value at 20 to 30°C to a small value of 4 to 7%, it is possible to reduce the impact resilience value at environmental temperatures of about 10 to 40°C, where printing devices such as typewriters are normally used. It is also possible to reduce the temperature dependence, and therefore the hammer energy efficiency is improved over the entire environmental temperature range, and the temperature dependence of printing performance can also be improved compared to the conventional method.

FIG. 1 shows a sectional view of an example of the platen roller of the present invention.

As shown in FIG. 1, the platen roller of the present invention is basically constructed by having a core material 7 surrounded by a rubber material 8 having the above-mentioned hardness and impact resilience values. 1. The core material 7 can be formed from metals such as stainless steel, aluminum, and mild steel, and resins such as phenol, styrene, melamine, and elastomer. This core material 7 preferably has sufficient rigidity and hardness to obtain the impact force necessary to obtain good printing performance.

As mentioned above, the rubber material 8 needs to have a hardness of 95±3 JISA at 20 to 25°C based on JIS K6301, and a rebound resilience value of 4 to 7% at 20 to 30°C based on JIS K6301. . Such hardness provides sufficient durability required for platen rollers used in printing devices such as typewriters and printers.

Rubber materials having such hardness and impact resilience values include, for example, raw material polymers (natural synthetic rubber and/or thermoplastic elastomer), carbon, and inorganic fillers that are used when compounding rubber materials for ordinary platen rollers. , oil, sulfur, vulcanization aids, vulcanization accelerators, stearic acid, and other peroxides as crosslinking agents, plasticizers, reinforcing agents, etc., as necessary, by adjusting the blending amounts accordingly. .

Specifically, for example, the concentration of a vulcanizing agent such as sulfur is increased (preferably 15 parts or more per 100 parts of rubber) to increase the concentration of carbon black in the filler, especially carbon black having a finer diameter than FEF. It is preferable to adjust the rubber material so that the weight occupied by the rubber is 50% or less.

Here, the raw material polymers include 5BR (styrene butadiene rubber), NBR (tolyl butadiene rubber), IR (
Rubbers such as isoprene rubber), NR to tolyl rubber), CR (chloroprene rubber), IIR (butyl rubber), BR (butadiene rubber), or RB (butadiene resin), 5B
Polystyrene-based elastomers such as S (styrene-butadiene-styrene elastomer), polyolefin-based, polyester-based, polyurethane-based, thermoplastic elastomers such as PVC (polyvinyl chloride), or blends thereof can be used.

As for carbon, I S A F (Intermed
iateSuper Abrasion Furnac
e), S A F (5uper^brasi
on Furnace), HA F (A ear ablation furnace black), F E F (Fas
t Extrusion Furnace), S RF
(Semi-Reinforcing Furnace
), F T (Fine Thermal), E P
C (Easy Processing Channel)
, MPC (Medium Processing)
Channel) or a blend thereof can be used.

As the inorganic filler, it is also effective to use calcium carbonate, various clays, talc, etc., or blends thereof, and silica-based fillers such as hydrous silicates, anhydrous silicic acid, and their respective salts.

As softeners, those based on vegetable oils such as aromatic, naphthenic and paraffinic ones, and those based on mineral oils such as paraffin wax and mineral rubber are also used. Factices are also used.

As the vulcanization accelerator, metal oxides such as zinc white and magnesia, and fatty acids such as stearic acid are used.

Vulcanization accelerators include aldehyde amines, guanidines, thiazoles, thiurams, geocarbamates,
Xanthates and the like and various combinations thereof are used.

Examples of crosslinking agents include peroxides such as dicumyl peroxide, ditertiary butyl peroxide, and benzoyl peroxide, localized sulfur thereof, organic sulfur-containing compounds, metal oxides, quinone dioximes, organic polyvalent amines, and modified phenolic resins. used.

Plasticizers include DBP (dibutyl phthalate) and DOP.
Phthalates such as (dioctyl phthalate), adipates such as DOA (dioctyl adipate), sebacates such as DOS (dioctyl sebacate), phosphates such as TCP (tricresyl phosphate), and polyethers, Polyester type etc. are used.

Further, as the organic reinforcing agent, high styrene resin, phenol resin, modified melamine resin, etc. can be effectively used.

Further, as the tackifier, coumaron-indene resin, phenol-terpene resin, rosin derivative, etc. can be appropriately used.

Further, as anti-aging agents, various combinations of aldehydes, ketones, amines and derivatives thereof, wax-based ones, and stiff straws are used.

In addition, xylyl mercaptan, 2-
Benzamide thiophenol, zinc salt, etc. are used.

〔Example〕

Hereinafter, the present invention will be explained in more detail based on Examples.

Example 1 A rubber composition having the formulation shown in Table 1 was press-vulcanized at 140° C. for 70 minutes to obtain a rubber material. The hardness and impact resilience value of this rubber material are 93JIS 8 (20℃, JISK
6301), rebound resilience is 6% (20℃, JISK6
301').

1st grade compound material weight part SBR150
2100 TSAF Carphone 20 Mild Calcium Carbonate 13070 Maoil
lO zinc oxide
3 Stearic acid 2 Accelerator CZ 1 Accelerator TS
O,2 sulfur
35 The above rubber material was replaced with a stainless steel core material having the shape shown in Fig. 1 (outer diameter: 22 mm, inner diameter: 1
6ma+, length 2400m11) thickness 7+nm
The platen and roller of the present invention were obtained by laminating the platen and roller.

゛ When this platen roller was attached to a printing device having a one-color molded dage foil as shown in the third figure and printing was performed, the letters of the alphabet large H were printed.
Good printing was possible with extremely small impact energy of about 7 mJ. In addition, although such printing was performed continuously for 100,000 characters, no particular change in printing performance was observed.

Example 2 A rubber composition having the formulation shown in Table 2 was press-vulcanized at 140° C. for 60 minutes to obtain a rubber material. The hardness and rebound resilience value of this rubber material is 97JTS^ (20℃, JISK
6301), rebound resilience is 4.5% (20℃, JIS
K6301).

1 Presentation 1 Compounding material Part by weight SBR150
2100 ISAF Carbon 30 Minor Calcium Carbonate 170 Aroma Oil
I5 Zinc white 3 Stearic acid 2 Accelerator CZ
1// T So
, 2
40 A platen roller was prepared in the same manner as in Example 1 except that the above rubber material was used, and printing was performed. Good printing was possible with the same small impact energy as in Example 1. In addition, although such printing was performed continuously for 100,000 characters, no particular change in printing performance was observed.

Comparative Example 1 A rubber composition having the formulation shown in Table 3 was press-vulcanized at 140° C. for 70 minutes to obtain a rubber material. The hardness and rebound resilience value of this rubber material is 93JIS A (20℃, JIS
S K6301), rebound resilience is 10% (20℃, J
ISK6301).

1 Main ball compounding material Weight part SBR150
2100 ISAF Carbon 20 Minor Calcium Carbonate 80 Aroma Oil
7 Zinc white 3 Stearic acid 2 Accelerator C7
1 // TSO, 2i
Oh
30 A platen roller was made in the same manner as in Example 1 except that the above rubber material was used, and printing was performed.
A large impact energy of about 25 mJ was required in order to perform good printing on alphabet large H type characters. Furthermore, when such printing was performed continuously, characters were missing after about 10,000 characters.

(Effects of the Invention) As explained above, the platen roller of the present invention with a reduced impact resilience value not only provides good printing performance and excellent type durability, but also resists changes in environmental temperature. It is also possible to ensure stable printing performance even in the case of printing.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of an example of a platen roller of the present invention, FIG. 2 is a sectional view of an example of a conventional platen roller, and FIG. 3 is a diagram illustrating a printing state. 1.7...core material 2.8--rubber material 3...
Printing paper 4... Ink ribbon 5... Dage foil 6... Printing hammer PJ1 Figure 2 Figure 3

Claims (1)

[Claims] (1) Around the core material 20~ based on JIS K6301
A platen roller equipped with a rubber material having a hardness of 95±3 JIS A at 25°C and a rebound resilience value of 4 to 7% at 20 to 30°C based on JIS K6301.