JPS62284766A - Platen roller - Google Patents

Abstract

PURPOSE:To obtain a platen roller free of possibility of defective printing even when the temperature thereof raised, by fitting a rubber member containing specified amounts of a cross-linking agent and a filler and containing a softener and a plasticizer in a specified total amount to the periphery of a core member. CONSTITUTION:A rubber member is used which contains a filler in an amount of 35-70wt% to obtain a high impact strength, contains a cross-linking agent in an amount of 2-11wt% so as to have a glass transition point in a service temperature range thereby enhancing a shock-absorbing capability, and contains a softener and a plasticizer in a total amount of 6-13wt% to maintain the high shock-absorbing capability. The rubber member can be obtained by blending a raw material polymer, carbon, an inorganic filler, an oil, sulfur, a vulcanizing assistant, a vulcanization accelerator and a peroxide as a cross-linking agent, a plasticizer, a reinforcing agent or the like. The inorganic filler may be calcium carbonate, clay or the like or a blend thereof. The softener may be a vegetable oil softener based on an aromatic compound, naphthene or the like or a mineral oil softener such as paraffin wax and mineral rubber. The plasticizer may be a phthalate plasticizer such as DBP and DOP, an adipate plasticizer such as DOA, or the like.

Description

Detailed Description of the Invention 3. 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 and problems]

Conventionally, printing devices such as typewriters have included a platen roller that acts as a base plate during printing. This platen roller usually has a core part 1 as shown in Figure 1.
It is a cylindrical object made by wrapping a rubber material or resin material 2 around it, and as shown in FIG. The struck daisy foil 5 is pressed, and the character of the daisy foil 5 is printed on the printing paper 3F.

The performance of printing on printing paper obtained as described in F is as follows:
The inventor of the present invention has confirmed through experiments that it depends on the impact load when the Daisy foil 5 is pressed. Impact 7 The load is determined by the hardness of the rubber material and the magnitude and speed of the force of the hammer impact. If this impact load is insufficient,
Printing defects occur, such as parts of characters being missing or the outlines of characters being unclear.

The present inventors believe that, as a result of their efforts, if the filler is blended within an appropriate concentration range (35 to 70% by weight),
It has been discovered that in order to obtain good printing performance, it is possible to obtain a rubber compound that can be subjected to partial impact loads and is taut.

Additionally, printing defects such as supplementary notes generally occur frequently when the environmental temperature is high. This defective printing occurs not only in manual typewriters, which are affected by impact loads or irregularities, but also in electronic typewriters, which apply a mechanical or constant impact force to the daisy foil, especially if printing continues for a long time. It has been observed that this phenomenon occurs more frequently when the temperature of the platen roller increases.

By the way, the present inventor discovered that printing performance is affected not only by the ICE load but also by the impact S damping capacity, and that increasing the impact S damping capacity represented by rebound resilience (reducing rebound resilience) improves printing performance. I discovered that it does get better. It has been found that in the case of rubber materials, the shock attenuation ability increases at temperatures near the glass transition point.

Furthermore, the present inventor has discovered that by blending a softener and a plasticizer at an appropriate concentration (6 to 13% by weight in total) in the rubber formulation, a rubber material that can maintain a high impact damping ability over a wide temperature range can be obtained. discovered.

(Object of the invention) The present invention has been made in view of the above circumstances,
The purpose is to provide a platen roller that does not cause printing defects, and in particular does not cause printing defects even when the temperature rises due to long-term use even at high environmental temperatures.

(Step 3 for Solving the Problems) The objective of the present invention is to apply 2 to 1
This is achieved by a platen roller equipped with a rubber material containing a total of 1 claw%, a filler of 35 to 70%, and a softener and a plasticizer of 6 to +3ff11% in total.

That is, in the present invention, a filler is blended at an appropriate concentration (35 to 70% by weight) in order to obtain a large impact load, and the glass transition point is set at a temperature normally used in order to increase the impact g11 ability in a temperature range that is normally used. 2 to 11% by weight of cross-linking agent was added to maintain the temperature within the temperature range, and a total of 6 to 13% by weight of softener and plasticizer was added to maintain VR performance over a wide range of environmental temperatures. It is made of rubber material.

The appropriate concentration of the filler is 35 to 70% by weight, preferably 40 to 65% by weight, more preferably 45 to 60% by weight.
Weight%.

The concentration of the crosslinking agent is preferably 2 to 11% by weight.

3 to +o, 5ffifft%, more preferably 4
~10% by weight.

-F Moderate concentration of total weight of softener and plasticizer 6-1
3% by weight is preferably 7-12% by weight, more preferably 7-II% by weight.

Adding a large amount of crosslinking agent (2 to 11% by weight) increases the hardness of the rubber material. Since the I load becomes larger, it is more effective in preventing the occurrence of printing defects.

In the present invention, the weight % of the crosslinking agent is the total weight % of sulfur, peroxide as a crosslinking agent, and other crosslinking agents.

The weight percent of the filler is the total ff1t% of carbon and an inorganic filler called white filler.

The rubber material of the platen roller of the present invention is made of a raw material polymer (
synthetic, natural rubber and/or thermoplastic elastomers), carbon, inorganic fillers, oils, sulfur, vulcanization aids, vulcanization accelerators, stearic acid, and if necessary peroxides as crosslinking agents, ol Ifj It is obtained by blending appropriate amounts of agents, reinforcing agents, etc.

Raw material polymers include SBR, NBR, IRlNR,
Rubber or RB such as CR, I IR, BR.

Thermoplastic elastomers such as SBS, polyolefin, polyester, polyurethane, PVC, or blends thereof are used.

Carbons include l5AF, SAF, and HAF.

FEF, SRF, FT, EPC, MPC or a blend thereof is 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 silicic acid, 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 accelerating aid, zinc shavings, total oxides such as magnesia, and fatty acids such as stearic acid are used.

As the vulcanization accelerator, aldehyde amines, guanidines, thiazoles, thiurams, dithiocarbamates, xanthates, etc., and various combinations thereof are used.

As a crosslinking agent, dicumyl peroxide, ditertiary
Peroxides such as butyl peroxide and benzoyl peroxide, their agglomerated sulfur, organic sulfur-containing compounds, metal oxides, quinone dioximes, organic polyvalent amines, modified phenolic resins, and the like are used.

Examples of plasticizers include phthalates such as DBP and DOP, and D
Adipate series such as OA, sebacate series such as DOS, TC
Phosphate-based materials such as P, as well as polyether-based materials, polyester-based materials, and the like are used.

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

Further, as a tackifier, coumaron-indene resin, phenol-terpene resin, rosin derivative, etc. are appropriately used.

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

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

〔Example〕

Example 1 Rubber as shown in Table 1 was put into a mold and heated to 149°C.
By vulcanizing for 60 minutes at
A cylindrical rubber material of JIS-A scale (measured at 20° C.) was obtained, and the platen roller of the present invention was obtained by attaching the rubber material to an aluminum core material. Use this platen roller as an electronic typewriter (Canon %, A
P36Q), and 1,000 characters were continuously printed on bank bond paper in an environment of 20° C. As a result, no printing defects occurred at all. Furthermore, when the same test was conducted in environments of 30° C. and 40° C., no printing defects occurred.

In addition, the rubber compound shown in Table 1 is molded (JIS
- 6301; for making test pieces for impact resilience test) and press vulcanized at 150°C for 60 minutes, and the impact resilience of the obtained test pieces was 7! at each temperature. l11 was determined. The results are shown in Table 2.

Example 2 A platen roller was made in the same manner as in Example 1 except that the rubber shown in the formulation table in Table 3 was used, and the same printing test was conducted. No defective printing occurred even in Iwawa in an environment of ℃.

Comparative Examples 1 to 4 Platen rollers were made in the same manner as in Example 1 except that rubbers whose formulations are shown in Tables 4 to 7 were used, and the same printing test was conducted in an environment of 10°C. In Tables 4 to 7, 3 pieces, 1 piece, 2 pieces, 1 piece, respectively.
35 defective prints occurred and 2. In an environment of 20℃, 0, 1, 3, and 140 defective prints occurred respectively for those in Tables 4 to 7, and in a 30℃ environment. Below, for Tables 4 to 7, 0, 2, and 6, respectively.
255 defective prints occurred, and in an environment of 40℃, 2 and 5 defective prints occurred for those in Tables 4 to 7, respectively.
There were 9 and 510 defective prints.

[Reference example]

Using a large number of platen rollers using rubber materials of various formulations containing 0.1 to 0.1 to 0.1 to 0.1% market weight of crosslinking agents, each platen roller was installed in the same printer as in Example 1, and the rubber material portion was heated to 0.degree.
! While maintaining the temperature at 5°C intervals from 00°C, 1000 characters were continuously printed and the number of defective prints that occurred was measured.

Judgment of 1ft11 constant results is based on defective printing of 10 characters or more (characters are missing, some ink is missing, printing/outlines are unclear, print density is uneven). , and those below that were considered to have good printing quality. When we plotted the compounding concentration of the crosslinking agent for each rubber material and the temperature of the platen roller, we could clearly see that there were areas with poor printing and points with good printing, and we drew the boundary line between them, as shown in Figure 3. A graph like the one shown is obtained.

As can be seen from the graph, the platen roller using a rubber material containing 2 to I+% by weight of a crosslinking agent has a temperature range of 0°C to 5°C.
It can be said that printing defects do not occur even when used at a temperature of 0°C.

Table 1 Table 2 Table 3
Table 4 Table 5
Table 6 Table 7 [Effects of the Invention] As described above, the platen roller of the present invention can obtain high-quality printing for a long time even at high environmental temperatures, and has a low concentration of crosslinking agent and filler. Since it can be obtained by a simple operation of adjustment, it is possible to achieve an economical value of several hundred.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the platen roller of the present invention, Fig. 2 is a schematic diagram of the part of the printer where printing is performed, and Fig. 3 shows the compounding concentration of the crosslinking agent in the rubber material of the platen roller and its concentration. It is a graph showing the state in which the correlation with the usage temperature contributes to the quality of printing. ! = Core metal part 2: Rubber material (resin material) which is a hard elastic layer 3 Printing paper 4: Ink ribbon 5, Daisy foil 6゛Printing hammer case 2 Figure 1 Cage 1'' (Charge%) io'' 53 Figure

Claims (1)

[Claims] Around the core metal material, a crosslinking agent of 2 to 11% by weight, a filler of 35 to 70% by weight, and a total of 6 to 1% of a softener and a plasticizer are added.
A platen roller equipped with a rubber material containing 3% by weight.