JPH0719103B2 - Method of manufacturing elastic rotating body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a method for manufacturing an elastic rotating body used in office equipment such as a copying machine, a printer, and a word processor.

<Background Art> Conventionally, as an elastic rotating body used in a copying machine, a printer, a word processor, etc., one having a surface layer made of a rubber material such as EPDM, chloroprene rubber, urethane rubber, or silicone rubber has been used. It was These elastic rotators are mainly used for transporting paper to be printed, but they have drawbacks such as paper dust accumulating on the surface layer, stains such as ink and toner, and easy surface abrasion. Was able to withstand a few thousand to tens of thousands of passes.

Further, a fixing roller used in a copying machine, a printer or the like generally uses a heating roller having a heating source as an elastic rotating body, and the elastic rotating body used here performs paper passing in a heated state. There was a problem such as toner offset, and durability was extremely severe.

On the other hand, in order to solve the above-mentioned drawbacks, the applicant of the present invention applied an elastic material layer onto an elastic layer as shown in Japanese Patent Application No. 59-234780 and applied an elastic rotating body obtained by firing the resin material. is suggesting. It is known that when the elastic rotating body is baked during production, it is rapidly cooled to lower the crystallinity of the resin film on the surface and increase the film strength. However, if the elastic rotating body is not uniformly cooled during the rapid cooling, a partial heat shrinkage may occur between the elastic layer and the resin layer, resulting in a partial permanent deformation.

<Object of the invention> The object of the present invention is to eliminate the above-mentioned drawbacks, to form a uniform resin film by quenching after firing, and to further form a strong and smooth resin film on the elastic layer. It is to provide a manufacturing method of a rotating body.

<Summary of the Invention> In order to achieve the above object, the present invention is to apply a resin material on an elastic layer and bake the resin material at a temperature equal to or higher than its crystalline melting point while maintaining the elastic layer under low temperature heating. In the manufacturing method for manufacturing the elastic rotating body, the whole surface of the elastic rotating body is rapidly cooled at the same time after firing the elastic rotating body.

<Example> FIG. 1 is a perspective view of a fixing roller which is an elastic rotating body obtained by applying the present invention. The fixing roller 1 is provided with a rubber layer 3 which is an elastic layer having heat resistance such as silicon rubber or fluororubber on a cored bar 2, on which a tetrafluoroethylene resin (PTF) is provided.
E) A fluororesin 4 such as ethylene tetrafluoride-perfluoroalkoxyethylene copolymer (PFA) is applied, and then baked at a temperature not lower than the crystal melting point of the fluororesin to obtain a desired shape.

By the way, generally, a rubber roller coated with an unsintered resin needs to be heated to a temperature equal to or higher than the crystalline melting point of the resin as described above, but the rubber itself has rubber characteristics such as impact resilience and compression set, so that the temperature is high. When heated, it causes fumes and depolymerization. These not only hinder the formation of a good quality resin layer, but also impair the rubber properties of the rubber itself. Therefore, overheating of the rubber layer causes the roller to have no function of the rubber layer and no characteristics of the resin layer.

For these reasons, in the examples of the present invention, a firing method is used in which the rubber roller itself is kept under a low-temperature overheat that does not cause smoking or depolymerization, while the resin coating layer is provided with a high temperature above its crystalline melting point. did.

Specifically, a method of rapidly heating the unsintered resin on the surface while rapidly cooling the rubber layer from inside the core metal, or the dielectric loss tangent of the liquid resin (dispersion, enamel) itself is more than that of the rubber layer. In addition to the dielectric heating method (see FIG. 2) that utilizes the large size, any method that is suitable for this purpose is suitable for the present invention.

By this method, a thermal gradient is substantially formed in the rubber in the thickness direction, but the temperature lower than the endurance temperature of the rubber (for example, 200 ° C. or lower) is higher than the crystalline melting point of the unbaked resin (for example, It is given for about 5 to 10 minutes from the firing temperature of 250 ° C or higher). After this firing, the roller is quenched. By this quenching, a fired resin surface layer having a low crystallinity and sufficient resin properties is formed on the rubber roller in a strongly adhered state to the rubber roller and with a desired thickness.

Therefore, in the elastic roller 1, the lower layer rubber itself exhibits desired rubber properties almost in the same manner as before the resin layer formation, the surface resin layer exhibits completely baked resin properties, and the adhesive property of these layers is It is strong.

Next, for the elongation rate and tensile strength of the resin, take out only the resin film from the roller after manufacturing as a tanzaque type sample with a width of 15 mm × a length of 100 mm, and check this with a 20 mm gap between chucks and a 250 mm pulling speed.
It was measured by performing a tensile test at / min. As a result, the characteristics of the resin were directly obtained.

Regarding the peel strength of the resin, cuts are made with a cutter knife at intervals of 10 mm width in the circumferential direction of the roller, the partially peeled fluororesin layer is pulled by a tension meter, and the maximum value is taken as the peel strength. According to this example, a width of 20 g / 10 mm or more was obtained.

FIG. 2 shows a method of manufacturing the roller of this embodiment. The apparatus shown in FIG. 2 is a specific example of a heating system using both an induction heating apparatus and infrared external heating.
High frequency generated from magnetron 105 (950MHz ~ 2450MH
z), a waveguide 106 for transmitting the wave, an openable / closable resin container 102 having the metallic high-frequency reflection plate 103 connected to the waveguide, and two infrared rays for upper and lower infrared rays for external heating. It has a lamp 111 and a reflective shade.

In the resin container 102, a fan 100 for generating an air flow in the hollow of the elastic roller 1 and a fan 101 for generating an air flow in the container 102 are rotatable by a driving means outside the container. It is provided. The container has a handle 109 on the upper side and an arm 107 for positioning the flange 1A of the elastic roller 1 on the lower side, which can be opened and closed around a fulcrum 108.

110 is a control means of the device, which is a drive means 104 and a magnetron 10
5 and the infrared lamp 111 are operated by a variable timer (not shown) for a predetermined time by inputting a closed state of the container and a predetermined start signal.

Since the elastic roller 1 has a rubber layer as a lower layer and a resin dispersion on the surface, a large amount of high frequency waves are absorbed in the dispersion having a relative dielectric constant larger than that of the rubber layer. Therefore, the resin dispersion is rapidly heated to a high temperature by heating with a high frequency wave, infrared rays and a constant temperature bath, and is heated to a temperature higher than its firing temperature. At this time, the rubber layer has a low high-frequency absorptivity, so that the rubber layer is not heated to a temperature as high as that of the discharge purgen and is heated to a considerably lower temperature. This makes it possible to obtain the roller characteristics described above.

The rubber layer thickness and the resin thickness of the above-described embodiment are set as the predetermined thickness within the range of 0.1 mm to 1 mm for the former and the predetermined thickness within the range of 1 μ to 50 μ for the latter, and the present invention includes the preferred embodiment. The above thickness is represented by the average thickness of each layer,
Optimally, the minimum film thickness is preferable.

Although the above embodiment does not provide an adhesive layer between the resin layer and the rubber layer, the present invention also includes one having an adhesive layer.

The resin layer in the above-described embodiment preferably contains water having a high dielectric constant, and a resin such as silicone, polyimide, polyamide, or polyamideimide is applied.

The rubber layer of the above-mentioned example may be a rubber material such that the temperature below the melting point of the material of the resin layer is the durable temperature, and ethylene propylene rubber, a mixture of this rubber with other rubber, etc. are applied. It

The fixing roller 1 fired as described above can be rapidly cooled to obtain the smoothness of the resin film on the surface and sufficient adhesion of the resin film and the rubber layer.

However, when a rapid thermal gradient is locally generated on the surface of the fluororesin during the rapid cooling, only the fluororesin in that part undergoes extreme heat shrinkage, and the resin layer is partially wrinkled, resulting in unevenness on the surface. The drawbacks of This is because the resin layer that has melted and has not yet sufficiently formed a film is rapidly cooled only partly faster than the others, causing a heat shrinkage force to act, and the film strength to withstand this heat shrinkage force is the surrounding resin. Because it is not made in layers.

When such a phenomenon occurs, for example, when it is used as a fixing roller, there occurs a phenomenon in which fixing failure occurs only in a portion which is deformed due to heat contraction or toner offset is abnormally increased.

FIG. 3 is an explanatory diagram showing a case where a quenching step is provided in the continuous line. The fixing roller 1 is held by the block No. 42 via the flange 1A and passes through the shower chamber 41 at a constant speed. The water kept at a constant temperature between 15 ° C. and 35 ° C. flows through the pipe 43 and is blown out from the outlet 43A of the pipe 43 all at once. The water discharged from the pipe 43 is collected in the drainage channel 44 and circulates. The water in the pipe 43 is blown out all at once when the entire fixing roller 1 is completely in the water blowing portion. By blowing water as uniformly as possible over the entire surface of the fixing roller 1 in the circumferential direction and the axial direction in this manner, it is possible to obtain a uniform resin surface by eliminating the partially watered portion and the non-watered portion.

The length of the water blowing portion needs to be longer than the axial length of the fixing roller 1, and the amount of water blowing is
0.1m ³ / min or more is desirable and the moving speed of the fixing roller is 1m /
sec or less is desirable. If it is out of the above range, a part where water does not come into contact is likely to occur, and as described above, wrinkles due to heat shrinkage occur.

The elastic rotator manufactured in this way has a durability of more than 1 million sheets when used as a conveyance roller for general office equipment, and heat fixing of fixing devices used in copiers, printers, etc. When used as an application roller, it had a durability of 100,000 sheets or more, good fixing property and little offset.

<Effects of the Invention> As described above, in the process of firing the resin material in the elastic layer and then rapidly cooling the elastic rotating body, the entire surface of the elastic rotating body is rapidly cooled at the same time, so that a uniform and smooth coating film having no surface defects can be obtained. Can be formed, and the film strength is high, and the adhesive force between the resin film and the elastic layer can also be increased.

[Brief description of drawings]

FIG. 1 is a perspective view of an elastic rotating body showing an embodiment of the present invention, FIG. 2 is a sectional view of a dielectric heating device, and FIG. 3 is an explanatory view for explaining a quenching method of the present invention. 1 ... Elastic rotating body, 2 ... Core metal, 3 ... Elastic layer, 4 ... Resin coating.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masaaki Sakurai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Michio Shigenobu 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Inichiro Yamamoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (1)

[Claims] 1. A manufacturing method for manufacturing an elastic rotating body by applying a resin material onto an elastic layer and firing the resin material at a temperature equal to or higher than its crystal melting point while maintaining the elastic layer under heating at a low temperature. A method for manufacturing an elastic rotating body, which comprises simultaneously quenching the entire surface of the elastic rotating body after firing the elastic rotating body.