KR101385966B1 - An image fixing apparatus - Google Patents

Abstract

Provided is a fixing apparatus capable of reducing thermal / mechanical load on a fixing roller. The fixing apparatus 130 of the present invention is disposed in parallel with the fixing roller 131 and the fixing roller 131, and the unfixed toner of the recording medium P conveyed to the area in pressure contact with the fixing roller 131. The pressure roller 132 which fixes an image, and the external heating member 133 which heats the main surface of the fixing roller 131 are provided. The external heating member 133 of the fixing device 130 presses the heating belt 133b, which is a tubular elastic member having a heat source 133a therein, and the heating belt 133b to the fixing roller 131 to heat the heating belt ( And a belt guide 133c, which is a support member for rotatably supporting 133b.

Description

Fixing apparatus {An image fixing apparatus}

1 is a schematic block diagram showing the configuration of an image forming apparatus provided with a fixing apparatus according to a first embodiment of the present invention.

2 is a schematic block diagram showing the configuration of a fixing unit according to the embodiment.

3 is a schematic perspective view showing a fixing unit according to the embodiment;

It is a schematic block diagram which shows the structure of the fixing unit which concerns on 2nd Embodiment of this invention.

5 is a schematic plan view of FIG. 4.

Fig. 6 is a schematic block diagram showing the configuration of a fixing apparatus of a conventional radiation preheating method.

It is a schematic block diagram which shows the structure of the conventional multi-axis suspension belt heating system fixing apparatus.

<Description of Symbols>

100 image forming apparatus

110 paper feed unit

120 image forming unit

130 Fusing Unit

131 fixing roller

132 pressure roller

133 external heating element

133a heat source

133b heating belt

133c belt guide

134 heating belt pressing member

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing apparatus, and more particularly, to a fixing apparatus of an external heating method for heating a fixing roller from the outside using a belt.

In an image forming apparatus which forms an image on a recording medium using an electrophotographic image forming method such as a laser printer, a copying machine, a facsimile, or the like, it is necessary to fix the toner image transferred onto the recording medium to form a permanent image. As the fixing method of the toner phase, if the toner is largely classified, the toner is melted by heat and penetrated into the recording medium by pressure; To melt and penetrate the recording medium.

Currently, the fixing method using heat and pressure is the most used in the electrophotographic apparatus. This is because it has a relatively simple configuration and can obtain stable fixability in a wide range from low speed to high speed.

For example, a heat transfer fixing apparatus is constituted by a heating (fixed) roller containing a heat source and a pressure roller in pressure contact with the heating roller. The heating roller is made of a cylinder made of metal such as aluminum or iron, for example, and an elastic layer made of, for example, silicone rubber is formed on the main surface thereof, and a release layer made of, for example, PFA, is formed on the outermost surface thereof. Inside the metal cylinder, radiant heat sources, such as a halogen lamp, are provided, for example. In such a fixing apparatus, the entire heating roller is heated inside the heating roller by a radiant heat source, and the toner is melted and fixed by passing the recording medium on which the toner image has been transferred to a fixing nip formed between the pressing roller.

In the fixing apparatus having the above-described configuration, the heating roller is formed of a thick metal cylinder to withstand high fixing pressure, and its main surface has a thermal conductivity of about 0.5 to 0.8 in comparison with a metal having tens to hundreds of W / m · K. Since the elastic layer, the PFA layer, etc. which are made of very small silicone rubber were provided in W / m * K, heat capacity is large generally, and especially in the case of color fixation, it takes several minutes to warm up. For this reason, the return time from print standby was shortened by maintaining a fixing apparatus at a constant temperature during print standby. However, this response always consumes energy.

In order to reduce the power consumption and improve the heating efficiency, a fixing device of a radiation preheating method has been proposed (for example, Japanese Patent Laid-Open No. 2006-184623). The fixing apparatus 10 of the radiation preheating method shown in FIG. 6 includes a fixing roller 12 having a surface heated from the outside by an external heating means 13 having a heat source 13a therein, and a fixing roller 12. And a pressing roller 11 which is disposed in parallel with the roller and presses the outer circumferential surface of the fixing roller 12 to form the fixing nip. In this fixing apparatus 10, the external heating means 13 is installed in the vicinity of the conveying part for conveying the recording material P before fixing, so that the external heating means 13 can be removed before passing the recording material P through the fixing nip. By using the radiant heat, the recording material P and the toner T can be preheated.

Moreover, the fixing apparatus of the multi-axis suspension belt heating system is proposed about the said problem (for example, Unexamined-Japanese-Patent No. 2005-292714). The fixing apparatus 20 of the multi-axis suspension belt heating system shown in FIG. 7 includes a fixing roller 22 having a heating source 22a, a pressure roller 21 pressed against the fixing roller 22, and a suspension roller ( 23 and an endless belt 25 lengthened by a suspension roller 24 having a heating source 24a. The fixing device 20 having the above-described configuration can easily lengthen the heating nip width sufficiently (that is, lengthen the heating time) and also has a low mechanical load on the fixing roller 22.

However, in the above-mentioned fixing apparatus 10 of the radiation preheating method, the preheating of the recording material P and the toner T by the radiant heat or convection from the external heating means 13, especially when the printing speed is high. In the case of color fixing, the heating effect on the recording material P and toner T is very small. For this reason, it is difficult to speed up printing or to colorize.

In addition, the fixing apparatus of the multi-axis suspension belt heating system has a high manufacturing cost because of a complicated mechanism, and a large heat capacity of the entire heating unit including the suspension roller. For this reason, there exists a problem that heating efficiency is bad and a warm-up time becomes long. For this purpose, a fixing method using a thin belt made of a metal having a low heat capacity or, for example, PI (Polyimide) is proposed. It is necessary to install the release layer which consists of high manufacturing difficulty. For this reason, belt cost becomes very high, and the number of parts of the suspension mechanism for suspension of a belt also becomes large compared with the conventional two-roller fixing machine, and there exists a problem that the number of parts and cost in the fixing apparatus as a whole become very high.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide a novel and improved fixing apparatus capable of reducing the thermal / mechanical load on the fixing roller.

According to an aspect of the present invention for solving the above problems, there is provided a fixing roller, a pressure roller which is arranged in parallel with the fixing roller and fixes an unfixed toner image of a recording medium conveyed to an area in pressure contact with the fixing roller; There is provided a fixing apparatus including an external heating member for heating a main surface of the fixing roller. The external heating member of the fixing apparatus includes a cylindrical elastic member having a heat source therein, and a supporting member for pressing the cylindrical elastic member to the fixing roller and rotatably supporting the cylindrical elastic member.

According to the present invention, the cylindrical elastic member having a heat source therein can be pressure-contacted to the fixing roller to elastically deform along the outer circumferential surface of the fixing roller, thereby making it possible to enlarge the pressure-contacting portion of the cylindrical elastic member and the fixing roller. Thereby, the thermal load of the fixing roller can be reduced. Moreover, the pressing force which a cylindrical elastic member gives to a fixing roller is very small compared with the case of using an external heating roller. Thereby, the mechanical load of the fixing roller can be reduced.

Here, the support member slidably supports the cylindrical elastic member in the rotational direction of the cylindrical elastic member. The cylindrical elastic member rotates by the frictional force at the pressure contact portion with the fixing roller. At this time, the support member slidably supports the cylindrical elastic member so as not to interfere with the rotation of the cylindrical elastic member.

Moreover, a cylindrical elastic member is provided so that it may be pressed by the fixing roller in the upstream of a fixing roller rotation direction. The cylindrical elastic member is a member for heating the fixing roller. It is preferable that the fixing roller heated to the fixing temperature for fixing the toner reaches the pressure contact portion (fixing nip) with the pressure roller as soon as possible to heat the toner. Thus, the cylindrical elastic member is provided on the upstream side of the fixing roller rotation direction (the side opposite to the advancing direction of the fixing roller on the basis of the fixing nip).

The support member supports at least a portion and both ends of the outer circumferential surface of the cylindrical elastic member. Usually, the support members which support both ends of an elastic member prevent the separation of the cylindrical elastic member in the longitudinal direction and the circumferential direction, and the support member which supports a part of the outer peripheral surface normally functions to prevent the separation of the elastic member in the circumferential direction. do.

Moreover, a cylindrical elastic member is driven by the frictional force by the contact with a fixing roller. For this reason, it is not necessary to provide auxiliary members, such as a drive part and suspension roller, for rotationally driving a cylindrical elastic member. This can simplify the configuration of the external heating member and reduce the heat capacity of the entire external heating member.

The fixing apparatus of this invention is comprised so that the width of the contact part in the circumferential direction of a cylindrical elastic member and a fixing roller may become larger than the width of the contact part in the circumferential direction of a fixing roller and a pressure roller. Thereby, the heating efficiency of a fixing roller can be improved more. Moreover, the pressure contact part of a fixing roller and a pressure roller is formed so that the center angle of the fixing roller which connects both ends of the width | variety of the pressure contact part in the circumferential direction with the rotation center of a fixing roller may be 30 degrees or more. As a result, the width of the pressure-contacting portion in the circumferential direction of the fixing roller and the pressure roller becomes large, so that the fixing time is long and the fixing strength of the toner can be improved.

Moreover, you may perform the emissivity improvement process, such as black heat-resistant coating, on the inner surface of a cylindrical elastic member. A heat source is provided inside the cylindrical elastic member. The radiation rate improving treatment can be performed on the inner surface of the cylindrical elastic member to improve the radiation rate of the heat source.

On the other hand, the fixing roller is configured to include an elastic layer made of a heat-resistant elastic member having heat insulation. A release layer may be formed on the outermost circumferential surface of the fixing roller in order to prevent the toner to be fixed from adhering to the fixing roller.

EMBODIMENT OF THE INVENTION Preferred embodiment of this invention is described in detail, referring an accompanying drawing below. In addition, in this specification and drawing, the component which has a substantially the same function structure is attached | subjected with the same code | symbol, and redundant description is abbreviate | omitted.

(First embodiment)

First, based on FIG. 1, the image forming apparatus provided with the fixing apparatus which concerns on 1st Embodiment of this invention is demonstrated. Moreover, FIG. 1 is a schematic block diagram which shows the structure of the image forming apparatus provided with the fixing apparatus which concerns on this embodiment.

The fixing apparatus according to the present embodiment is provided in an image forming apparatus 100 such as a laser printer, a copying machine, a facsimile, or the like. As an example, the toner image is transferred in multiple stages to the paper P conveyed on the transfer belt 105 suspended by four rollers 107a, 107b, 107c, and 107d in FIG. The image forming apparatus 100 of the method of obtaining an image is shown. The image forming apparatus 100 includes a paper supply unit 110, an image forming unit 120, and a fixing unit 130.

The paper supply unit 110 is a unit for stacking the paper P for transferring the toner image formed by the image forming unit 120 described later to supply the paper P to the image forming unit 120.

The image forming unit 120 is a unit for forming a toner image to be transferred onto the paper P. In this embodiment, four image forming portions are used to form toner images of four colors (black, cyan, yellow, magenta). 120B, 120C, 120Y, and 120M. The image forming portions 120B, 120C, 120Y, and 120M each include a photosensitive drum 121 on which an electrostatic latent image is formed, a charging roller 122 that charges the main surface of the photosensitive drum 121, An exposure apparatus 123 for exposing a main surface of the charged photosensitive drum 121 to form an electrostatic latent image, a stirrer 124 for stirring the toner as a developer, and a toner supplied from the stirrer 124 for the photosensitive drum 121. A developing roller 125 for attaching an electrostatic latent image formed thereon to form a toner image, and a cleaning roller 126 for removing the toner remaining on the photosensitive drum 121 after transferring the toner image onto the paper P; Is done. Further, a transfer roller 127 for transferring the toner image onto the paper P is disposed to face the photosensitive drum 121 with the transfer belt 105 interposed therebetween.

The fixing unit 130 is a fixing device for fixing the toner image transferred to the paper P. FIG. The detailed configuration of the fixing unit 130 will be described later.

In the image forming apparatus 100, the paper P carried out from the paper supply unit 110 is conveyed to the image forming unit 120 by the transfer belt 105. The paper P passes through the photosensitive drum 121 and the transfer roller 127 together with the transfer belt 105 toner formed in each of the image forming portions 120B, 120C, 120Y, and 120M. The images are transferred sequentially. The paper P on which four toner images have been transferred by passing through the image forming unit 120 is conveyed to the fixing unit 130 and the toner images are fixed to the paper P. As shown in FIG.

In the above, the structure of the image forming apparatus 100 which concerns on this embodiment was demonstrated. Next, the structure of the fixing unit 130 which concerns on this embodiment is demonstrated based on FIG. 2 and FIG. 2 is a schematic block diagram showing the configuration of the fixing unit 130 according to the present embodiment. 3 is a schematic perspective view of the fixing unit 130 according to the present embodiment.

As shown in FIG. 2, the fixing unit 130 according to the present embodiment includes a fixing roller 131, a pressure roller 132, and an external heating member 133.

The fixing roller 131 is a roller for fixing the toner image transferred to the paper P, and is provided in pressure contact with the pressure roller 132 described later. As shown in FIG. 3, the fixing roller 131 includes a fixing roller rotating shaft 131a, an elastic layer 131b, and a release layer 131c. The fixing roller rotating shaft 131a is, for example, a metal core, connected to an external drive unit (not shown), and rotates in a counterclockwise direction. The elastic layer 131b is provided around the fixing roller rotating shaft 131a, and is formed of a member having a heat insulating property, and is made of, for example, foamable silicone rubber. The release layer 131c is formed around the elastic layer 131b and is made of a material having mold release properties so that toner does not adhere to the release layer 131c. The release layer 131c is formed by coating a fluororesin film such as PFA or PTFE or coating of these materials. In addition, a non-foamed silicone rubber layer having a thickness of about 0.2 to 3 mm is provided between the elastic layer 131b and the release layer 131c.

The pressure roller 132 is a roller which applies pressure for fixing the toner image transferred to the paper P, and is provided in pressure contact with the fixing roller 131 in parallel. As shown in FIG. 3, the pressure roller 132 includes a pressure roller rotation shaft 132a and an elastic layer 132b. The pressure roller rotation shaft 132a is an axis serving as the rotation center of the pressure roller 132, and is, for example, a metal core and is rotatably supported by a support member (not shown). An elastic layer 132b is formed around the pressure roller rotating shaft 132b. The elastic layer 132b is formed of a member having a heat insulating material, and is made of, for example, foamable silicone rubber.

The external heating member 133 is a member for heating the fixing roller 131, and includes a heating belt 133b and a belt guide 133c having a heat source 133a therein as shown in FIG. 3.

The heating belt 133b is an endless belt and is a cylindrical elastic member that heats the fixing roller 131. The heating belt 133b has heat resistance for continuous use in a state of being heated at about 150 to 200 ° C. by a heat source 133a such as a halogen lamp, and forms a heating nip with the fixing roller 131. In order to be pressed by the fixing roller 131 is formed of a material having a bending elastic. The heating belt 133b is formed of, for example, a metal such as stainless steel or nickel having a small heat capacity, or a heat resistant resin such as PI. Moreover, in order to improve the emissivity of the heat source 133a, you may perform the emissivity improvement process, such as black heat-resistant coating, on the inner peripheral surface of the heating belt 133b. Moreover, you may form the release layer which consists of PFA, PTFE, etc. on the outer peripheral surface of the heating belt 133b. Further, the heating belt 133b is positioned upstream of the fixing roller in the rotational direction of the fixing roller 131 based on the fixing nip so that the fixing roller 131 reaches the fixing nip as soon as possible after being heated by the heating belt 133b. It is better to install on the opposite side of the rotation direction.

The belt guide 133c is a supporting member that rotatably supports the heating belt 133b in order to maintain the state in which the heating belt 133b is in pressure contact with the fixing roller 131. The belt guide 133c is formed of a material having heat resistance, for example, a heat resistant resin, in order to support the heating belt 133b heated to about 150 to 200 ° C. The belt guide 133c supports the heating belt 133b so as to be slidable in the rotational direction. For this reason, the inner circumferential surface of the belt guide 133c is formed of a material which does not cause great friction between the outer circumferential surface of the heating belt 133b so as not to interfere with the rotation of the heating belt 133b.

For example, as shown in FIG. 3, the belt guide 133c is provided in the both ends and center part of the heating belt 133b. The belt guides 133c at both ends are provided so as to cover the circumferential direction and the end surface in order to suppress the separation of the heating belt 133b in the longitudinal direction, and the belt guide 133c at the center portion is the circumferential direction of the heating belt 133b. In order to suppress the separation of the heating belt 133b is installed so as to cover a part of the outer circumference. Moreover, the shape of the belt guide 133c is not limited to the said example, For example, you may make it the shape which covers the whole length direction opposite to the fixing roller 131 of the heating belt 133b.

The fixing unit 130 has an unfixed toner image at a pressure contact portion (hereinafter referred to as a “fixing nip”) of the fixing roller 131 and the pressure roller 132 heated by the external heating member 133. By passing the formed paper P, the toner is heated and pressurized to fix the toner image on the paper P. FIG. Here, in order to reduce the thermal / mechanical load to the said fixing roller 131 at the time of heating the fixing roller 131, in this embodiment, it heats using the heating belt 133b which is a cylindrical elastic member.

The external heating member 133 according to the present embodiment forms a heating nip by pressing the elastic heating belt 133b to the fixing roller 131 and bending the heating belt 133b. When the heating belt 133b is pressed against the fixing roller 131, the heating belt 133b is elastically deformed and bent along the main surface of the fixing roller 131. The heating belt 133b is bent to contact the fixing roller 131 to become a heating nip. Thus, wide heating nip can be formed by pressing the heating belt 133b to the fixing roller 131 and forming a heating nip. By increasing the heating nip width, the fixing roller 131 is not locally heated, thereby reducing the heat load on the surface of the fixing roller.

Moreover, since the heating belt 133b is an elastic member, the pressing force which presses the heating belt 133b to the fixing roller 131 is very small compared with the case of heating using an external heating roller or the like. Therefore, the mechanical load on the fixing roller 131 can be reduced, and the boundary peeling and surface abrasion of the release layer 131c and the elastic layer 131b of the fixing roller 131 can be prevented.

On the other hand, the heating belt 133b follows the fixing roller 131 which rotates counterclockwise, and rotates clockwise. In the heating nip, friction occurs because the release layer 131c of the fixing roller 131 and the release layer of the heating belt 133b come into contact with each other, while the friction force generated in the heating nip between the belt guide 133c and the heating belt 133b. The heating belt 133b can slide in the rotational direction along the belt guide 133c because it is comprised so that a larger friction force may not generate | occur | produce. For this reason, the heating belt 133b can rotate by the frictional force which arises in a heating nip. In addition, the frictional force causes tension on the heating belt 133b at the pressure contact portion (heating nip) of the heating belt 133b and the fixing roller 131, while tension is applied to the heating belt 133b at the portions other than the heating nip. Do not. In this manner, the tension of the entire heating belt 133b is prevented from causing the heating belt 133b to be hardly twisted, thereby preventing the heating belt 133b from being cracked or broken.

Such an external heating member 133 does not require an auxiliary member such as a suspension roller, and can be configured very simply. Therefore, the heat capacity of the entire external heating member 133 is reduced to improve the thermal efficiency. Thereby, the time (warming up time) required for heating the fixing roller 131 to the fixing temperature can be shortened, thereby reducing the cost.

In the above, the fixing unit 130 which concerns on 1st Embodiment was demonstrated. The fixing unit 130 is configured to press the heating belt 133b, which is a cylindrical elastic member having a heat source 133a therein, to the fixing roller 131 so as to be rotatably supported by the belt guide 133c serving as the supporting member. . Thereby, the heating nip which is the pressure contact part of the heating belt 133b and the fixing roller 131 can be increased, and the pressing pressure from the heating belt 133b to the fixing roller 131 also reduces. Therefore, the thermal / mechanical load on the fixing roller 131 can be reduced. Moreover, since the structure of the external heating member 133 can be simplified, the heat capacity of the whole external heating member becomes small, and thermal efficiency can be improved.

(Second Embodiment)

Next, the fixing unit 130 which concerns on 2nd Embodiment of this invention is demonstrated based on FIG. 4 and FIG. 4 is a schematic block diagram showing the configuration of the fixing unit 130 according to the present embodiment. 5 is a schematic plan view of FIG. 4. The fixing unit 130 which concerns on this embodiment differs in the point which provided the press member in the inner peripheral surface of the heating belt 133b compared with 1st Embodiment. Hereinafter, the difference with the fixing unit 130 which concerns on 1st Embodiment is mainly demonstrated.

As shown in FIG. 4, the fixing unit 130 according to the present embodiment includes a fixing roller 131, a pressure roller 132, an external heating member 133, and a heating belt pressing member 134. The fixing roller 131, the pressure roller 132, and the external heating member 133 are the same members as in the first embodiment.

The heating belt pressing member 134 is provided to improve the adhesiveness between the heating belt 133b of the external heating member 133 and the fixing roller 131. The heating belt pressing member 134 is, for example, a plate-shaped member provided inside the heating belt 133b and is in contact with the inner circumferential surface of the heating belt 133b to press the contact portion of the heating belt 133b and the fixing roller 131 ( Heating nip) is provided to press on the fixing roller 131 side. Both ends of the heating belt pressing member 134 are supported by elastic members 135 such as springs, for example.

The heating belt pressing member 134 has a heat resistance to heat from the heat source 133a and the heating belt 133b, and has a high thermal conductivity such as metal or ceramic so as not to interfere with heating of the fixing roller 131. And the like. Moreover, in order to raise a radiation ratio, you may perform the radiation rate improvement process, such as black heat-resistant coating, on the side facing the heat source 133a of the heating belt press member 134.

As described above, the heating belt 133b is elastically deformed along the outer circumferential surface of the fixing roller 131 by its elasticity when pressed by the fixing roller 131. At this time, the pressure contact portion of the heating belt 133b and the fixing roller 131 becomes a heating nip to heat the fixing roller 131 by the heating belt 133b, but the heating belt 133b and the fixing roller 131 When the adhesion is low, the heating efficiency of the fixing roller 131 is lowered. Thus, the heating belt 133b is pressed toward the fixing roller 131 by the heating belt pressing member 134 in order to ensure the heating belt 133b and the fixing roller 131 are in close contact with each other. Here, the pressing force by the heating belt pressing member 134 is such that a mechanical load (for example, boundary peeling of the surface of the fixing roller 131, elastic wear, etc.) is not applied to the fixing roller 131. It is good to set.

In the above, the fixing unit 130 which concerns on 2nd Embodiment of this invention was demonstrated. In the fixing unit 130, the fixing unit 130 according to the first embodiment further includes a heating belt pressing member 134 for bringing the heating belt 133b and the fixing roller 131 into close contact with each other. Thereby, the fixing roller 131 can be heated more efficiently than the first embodiment by making sure that the heating belt 133b and the fixing roller 131 are in close contact with each other.

As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it goes without saying that this invention is not limited to the said example. It will be apparent to those skilled in the art that various modifications or variations can be made within the scope of the claims, and they are naturally understood to belong to the technical scope of the present invention.

For example, in the said embodiment, although the cylindrical elastic member was an endless belt, this invention is not limited to the said example. For example, a tube made of an elastic body may be used.

As described above, according to the present invention, it is possible to provide a fixing apparatus capable of reducing the thermal / mechanical load on the fixing roller.

Claims (11)

A fixing roller, a pressure roller which is disposed in parallel with the fixing roller and fixes an unfixed toner image of a recording medium conveyed to an area in pressure contact with the fixing roller, and heats a main surface of the fixing roller. With an external heating element, The external heating member, A cylindrical elastic member having a heat source therein, and a supporting member for pressing the cylindrical elastic member to the fixing roller and rotatably supporting the cylindrical elastic member, Wherein the support member comprises: A fixing device characterized by supporting at least a portion and both ends of an outer circumferential surface of the tubular elastic member. The fixing device according to claim 1, wherein the support member supports the cylindrical elastic member so as to be slidable in a rotational direction of the cylindrical elastic member. The fixing device according to claim 1 or 2, wherein the cylindrical elastic member is pressed by the fixing roller at an upstream side of the fixing roller rotation direction. delete The fixing device according to claim 1, wherein the cylindrical elastic member is driven by a frictional force caused by contact with the fixing roller. The fixing device according to claim 1, wherein the width of the pressure contact portion in the circumferential direction of the cylindrical elastic member and the fixing roller is larger than the width of the pressure contact portion in the circumferential direction of the fixing roller and the pressure roller. The press-contacting portion of the fixing roller and the pressing roller is formed such that the center angle of the fixing roller connecting the rotational center of the fixing roller and both ends in the circumferential direction of the pressing-contacting portion is 30 ° or more. Fixing device. The fixing device according to claim 1, wherein an inner surface of the cylindrical elastic member is coated with a black heat-resistant coating. The fixing apparatus according to claim 1, wherein the fixing roller has a heat-resistant elastic member having heat insulation. The fixing apparatus according to claim 1, wherein the fixing roller has a release layer on its outermost circumferential surface. The method according to claim 1, And a heating belt pressing member which is provided on an inner circumferential surface of the cylindrical elastic member and presses the cylindrical elastic member toward the fixing roller side.

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