JPH08194400A - Fixing roller and fixing device formed by using the same roller - Google Patents

Abstract

PURPOSE: To obtain a fixing roller of a long life type and a fixing device suitable for high-speed fixing by providing the fixing roller with a cylindrical arbor material, a thermosetting resin layer dispersed with conductive power and solid lubricant and a release type resin layer without contg. the conductive powder. CONSTITUTION: The arbor material 4 is formed of metals, such as, for example, aluminum and copper. The surface of the arbor material 4 is provided with the thermosetting resin layer 3 contg. the conductive powder and the solid lubricant. Further, the surface of the thermosetting resin layer 3 is provided with the release type resin layer 2 contg. the solid lubricant and without contg. the conductive powder. Even if, therefore, the release type resin layer 2 wears and the thermosetting resin layer 3 formed thereunder is exposed on the surface of the fixing roller, the release property possessed by the thermosetting resin layer 3 is assured and the continuation of the fixing operation is possible, insofar as the conductive powder dispersed in the thermosetting resin layer 3 is not much exposed on the surface of the fixing roller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing roller and a fixing device using the same.

[0002]

2. Description of the Related Art In image forming apparatuses such as laser printers, copiers, and facsimiles, demands for higher image recording speed are increasing year by year. In order to increase the image recording speed (specifically, A4 paper conversion speed of 100 pages / minute or more), it is necessary to enable the fixing process in a short time.

[0003]

In order to speed up the fixing process in a fixing device having a pair of fixing rollers, conventionally, the temperature itself of a heating body for heating the fixing roller is set high or the surface of the fixing roller is fixed. By providing the coating layer with a small film thickness, it has been considered that the thermal efficiency of the recording material from the fixing roller is improved and the amount of heat to the recording material that is insufficient due to the increase in speed is supplemented. However, even if the film thickness of the surface coating layer is thin as in the latter case, considering the life of the fixing roller such as abrasion due to friction with the recording material, the film of the surface coating layer has been formed in the conventional fixing roller configuration. The thickness is limited to about 20 μm. An object of the present invention is to provide a fixing roller having a surface coating layer having a long life. Another object of the present invention is to realize a fixing device capable of supporting high-speed fixing.

[0004]

The above object is to provide a thermosetting resin formed on a core metal material by a cylindrical core metal material and a thermosetting resin in which conductive powder and a solid lubricant are dispersed. This is achieved by obtaining a fixing roller having a layer and a releasing resin layer formed on the thermosetting resin layer by the releasing resin containing no conductive powder. Further, the above object has a pair of rotating bodies that are in pressure contact with each other and a heating body that heats at least one rotating body, and by passing a recording medium having an unfixed image between the pair of rotating bodies. In a fixing device for fixing, at least one of the rotating bodies has a thermosetting resin layer containing conductive powder and a solid lubricant on a core metal material, and further contains conductive powder on it. This is achieved by having no releasable resin layer.

[0005]

According to the present invention, even if the releasing resin layer is worn and the thermosetting resin layer provided thereunder appears on the surface of the fixing roller, it is dispersed in the thermosetting resin layer. If a large amount of the conductive powder is not exposed on the surface of the fixing roller, the releasability of the thermosetting resin layer is secured and the fixing operation can be continued. By using this fixing roller, a fixing device suitable for high-speed fixing can be realized.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a fixing device according to the present invention, and FIG. 2 is an explanatory diagram showing a structure of a coating layer of a fixing roller according to the present invention. In FIG. 2, reference numeral 4 denotes a core metal material, and the core metal material 4 is formed of a metal such as aluminum or copper. A thermosetting resin layer 3 containing a conductive powder 10 and a solid lubricant is provided on the core metal material 4, and a solid lubricant is further contained on the thermosetting resin layer 3 and a conductive powder is contained. The releasable resin layer 2 that does not include is provided.

The thermosetting resin forming the thermosetting resin layer 3 is made of, for example, a polyimide resin or a silicone resin,
Further, the releasing resin forming the releasing resin layer 2 is made of, for example, a polyimide resin, a silicone resin or a fluororesin. Conductive powder 10 contained in thermosetting resin layer 3
For example, a metal oxide, aluminum metal powder or carbon black is used as the solid lubricant, and a fluorine resin (PFA (perfluoroalkoxy) or PTFE is used as the solid lubricant.
A fluororesin containing (polytetrafluoroethylene) as a component is preferable. ), Molybdenum disulfide or graphite is used. In the present embodiment, the thermosetting resin layer 3 has a configuration in which a fluorine resin as a solid lubricant and an aluminum metal powder as a conductive powder are dispersed in a polyimide resin, and the release resin layer 2 is a polyimide resin. It has a structure in which a fluororesin is dispersed as a solid lubricant. Here, by using a polyimide resin as the base resin of the releasable resin layer 2 and the thermosetting resin layer 3 and using the same basic components, mutual adhesion can be improved.

In this embodiment, the fixing roll having the above structure was used as a heating roller as shown in FIG. FIG.
1 indicates a heating roller. The core metal material 4 constituting the heating roller 1 is made of aluminum and is formed as a hollow cylindrical member having a thickness of about 8 mm.
Is housed. Since the structure of the coating layer formed on the core metal member 4 is as described above, the same reference numerals are given and the description thereof is omitted. A pressure roller 7 is provided in the vicinity of the heating roller 1 so as to be in pressure contact with the heating roller 1. The pressure roller 7 includes a rubber layer made of silicon rubber having a thickness of 5 to 8 mm on a core metal made of aluminum, and a resin layer made of PFA having a thickness of about 100 μm on the rubber layer. It is configured by providing. The recording material 6 on which the unfixed toner image is formed by the well-known electrophotographic technique is sent to the pressure contact portion of the heating roller 1 and the pressure roller 7 along the guide plate 9, and the unfixed toner image is sufficiently formed at this pressure contact portion. Then, it is heated, melted, and pressurized to be fixed on the recording material 6. The recording material 6 sent out from the pressure contact portion between the heating roller 1 and the pressure roller 7 is sent out to the next step by the discharge roller 8.

When fixing is carried out by a fixing device equipped with such a heating roller, the releasable resin layer 2 is worn and the thermosetting resin layer 3 provided thereunder appears on the surface of the heating roller 1. Also, if a large amount of the conductive powder 10 dispersed in the thermosetting resin layer 3 is not exposed on the surface of the heating roller 1, the fixing operation is sufficiently continued due to the releasability of the thermosetting resin layer 3. can do.

In the heating roller of this embodiment, first, the thermosetting resin layer 3 is applied on the core metal 4 made of aluminum, and then the releasable resin layer 2 is applied. It is obtained by firing at 400 ° C. Based on such a procedure, a heating roller having an outer diameter of about 100 mm, a thickness of the releasable resin layer 2 of 1 to 5 μm, and a sum of the thickness of the releasable resin layer 2 and the thickness of the thermosetting resin layer 3 is about 20 μm. We produced a product and carried out high-speed fixing, and obtained results that could meet the specifications.

In manufacturing the fixing roller, in order to improve the adhesiveness between the core metal member 4 and the thermosetting resin layer 3,
An adhesive layer may be provided, alumite treatment may be performed, or the surface of the core metal material 4 may be processed by sandblasting or the like to have a roughness of about 1 to 10 μm.

[0012]

Comparative Example FIG. 3 shows a comparative example. In FIG. 3, reference numeral 4 denotes a core metal material, and the core metal material 4 is formed of a metal such as aluminum or copper. A thermosetting resin layer 3 containing a conductive powder 10 and a solid lubricant is provided on the core metal material 4, and a particle size smaller than that of the conductive powder 10 is provided on the thermosetting resin layer 3. A releasable resin layer 2'containing a small conductive powder 11 and a solid lubricant is provided. In the case of this configuration, since the conductive powder 11 is present in the releasable resin layer 2 ', if the thickness of each layer is set to the same dimension as in the configuration of FIG. It will reach the end of its life before it appears in the mold release resin layer 2 '.
2 is thicker than that of FIG. 2 and the conductive powder 11 is segregated in the releasable resin layer 2'to the thermosetting resin layer 3 side, so that high-speed fixing can be achieved. It was

[0013]

As described above, according to the present invention, a long-life fixing roller can be provided. Further, by adopting this fixing roller, a fixing device suitable for high speed fixing can be realized.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a schematic configuration of a fixing device according to the present invention.

FIG. 2 is an explanatory diagram showing a structure of a coating layer of a fixing roller according to the present invention.

FIG. 3 is an explanatory diagram showing a comparative example.

[Explanation of symbols]

2 ... Releasable resin layer, 3 ... Thermosetting resin layer, 4 ... Core metal material, 10 ... Conductive powder

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yudai Nakamura 1060 Takeda, Hitachinaka City, Ibaraki Prefecture Hitachi Koki Co., Ltd.

Claims (9)

[Claims] 1. A cylindrical core metal material, a thermosetting resin layer formed on the core metal material by a thermosetting resin in which conductive powder and a solid lubricant are dispersed, and conductive powder. And a releasing resin layer formed on the thermosetting resin layer by a non-releasing resin. 2. The fixing roller according to claim 1, wherein the conductive powder is metal oxide, aluminum metal powder or carbon black. 3. The fixing roller according to claim 1, wherein the solid lubricant is fluororesin, molybdenum disulfide or graphite. 4. The fixing roller according to claim 1, wherein the thermosetting resin is a polyimide resin or a silicone resin. 5. The fixing according to claim 1, wherein the release resin is a polyimide resin containing the solid lubricant or a silicone resin containing the solid lubricant. roller. Fluororesin 6. The fixing roller according to claim 1, wherein the releasing resin is a fluororesin. 7. The release resin layer has a thickness of 1 μm or more, and the sum of the thickness of the release resin layer and the thermosetting resin layer is 50 μm or less. The fixing roller according to claim 1. 8. The fixing roller according to claim 1, wherein the releasing resin layer and the thermosetting resin layer have substantially the same basic components. 9. A pair of rotating bodies which are in pressure contact with each other, and a heating body which heats at least one rotating body, and fixing is performed by passing a recording medium having an unfixed image between the pair of rotating bodies. In the fixing device, at least one of the rotating bodies has a thermosetting resin layer containing conductive powder and a solid lubricant on a core metal material, and further does not contain conductive powder. A fixing device having a releasable resin layer.