JP2001092281A - Fixing device and image-forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing device and an image-forming device, realizing high speed fixing and obtaining excellent fixing property by uniform and stable temperature, while maintaining power saving and warm-up performance. SOLUTION: This fixing device is constituted of a film-type rotating member provided in a state, where a fixed heating element is inscribed, and a roll-type rotating member for heat ray fixing provided to be opposed to the film-type rotating member, and equipped with a cylindrical light transmitting base substance possessing a heat ray irradiating means for radiating a heat ray inside and having light transmissivity to the heat ray, a light transmissive elastic layer on the outside of the light transmissive base substance and a heat ray absorbing layer absorbing the heat ray on the outside of the light transmitting elastic layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a quick start fixing device used for a copying machine, a printer, a facsimile, and the like, and an image forming apparatus using the fixing device.

[0002]

2. Description of the Related Art Conventionally, as a fixing device used in an image forming apparatus such as a copying machine, a printer, a facsimile, etc., a heat roller fixing method has been used as a fixing device having high technical perfection and stability. Machine to full-color machine,
Has been widely adopted.

However, in a conventional heat roller fixing type fixing device, it is necessary to heat a fixing heat roller having a large heat capacity when heating a transfer material or toner. And also
There is a problem that it takes time to warm up the fixing device during printing, and the printing time (warming-up time) becomes longer.

In order to solve this problem, a film (heat fixing film) is used, the heat roller is brought to the ultimate thickness of the heat fixing film to reduce the heat capacity, and a fixed heating element (ceramic heater) or an induction heating element whose temperature is controlled. Fixing device of the film fixing method and image forming device using it, which greatly improves the heat conduction efficiency by directly contacting the heat fixing film with the heat fixing film, and achieves energy saving and quick start that requires almost no warm-up time. Have been proposed and used recently.

Further, as a modification of the heat roller, a transparent substrate is used as a heat ray fixing roller (rotating member for heat ray fixing), and the toner is heated and fixed by irradiating the toner with heat rays from a halogen lamp (heat ray irradiation means) provided inside. In addition, a fixing method that achieves a quick start without requiring a warm-up time and an image forming apparatus using the same are disclosed in JP-A-52-106741, JP-A-57-82240, and JP-A-57-102736.
And JP-A-57-102741. In addition, a light absorbing layer is provided on the outer peripheral surface of the light transmitting substrate to constitute a heat ray fixing roller (rotating member for heat ray fixing), and a light from a halogen lamp (heat ray irradiation means) provided inside the cylindrical light transmitting substrate is provided. A fixing method for absorbing light by a light absorbing layer provided on the outer peripheral surface of a light transmitting substrate and fixing a toner image by heat of the light absorbing layer and an image forming apparatus using the same are disclosed in
No. 65867.

Conventionally, in double-sided copying, an image on one side formed on an image carrier is transferred and fixed on a transfer material, and this is temporarily stored in a two-sided reversing feeder, and is again placed on the image carrier. In this method, a transfer material is fed from a two-sided reversing feeding device in synchronization with an image formed on the transfer material, and an image on the other surface is transferred and fixed on the transfer material.

As described above, in the double-sided image forming apparatus, as described above, the transfer of the transfer material such as feeding to the two-sided reversing feeder and passing through the fixing device twice is performed, so that the reliability of transfer of the transfer material is improved. It was low and caused the transfer material to jam or wrinkle.

On the other hand, JP-B-49-37538 and JP-B-54-28740, and JP-A-1-44457.
Japanese Patent Application Laid-Open Nos. 4-214576 and 4-214576 propose a method in which a toner image is formed on both surfaces of a transfer material using an image carrier and an intermediate transfer member and then fixed once.

Further, the present inventors arrange a plurality of sets of toner image forming means including a charging means, an image writing means, a developing means, etc. around a photosensitive drum (image carrier), and place the toner image forming means on the photosensitive drum. The formed superimposed color toner image is once transferred onto a belt-shaped intermediate transfer body at one time, and then a superimposed color toner image is formed again on the photoconductor drum, and the toner image on the photoconductor drum and the intermediate transfer body are formed again. The toner image on the photosensitive drum is transferred as a front image to both surfaces of the transfer material that is fed in time with the toner image of the intermediate transfer member and is conveyed by the intermediate transfer member, and the toner image on the intermediate transfer member is transferred to the back surface. JP-A-9-258492 discloses an image forming apparatus and an image forming method (one-pass double-sided image forming method) for forming a two-sided color image by transferring a toner image on a transfer material by a fixing unit after transferring the image. It disclosed in Japanese Unexamined and Hei 9-258516 Patent Gazette.

[0010]

However, a fixing device using a method of fixing a toner image on a transfer material by a heat fixing film (film-like rotating member) using the above-described ceramic heater (fixed heating element) or induction heating element, In an image forming apparatus using this, energy saving and a quick start in which a warm-up time is shortened are achieved. Since the film uses a fixed heating element or an induction heating element, each of the films has a fixing property of a hard roller, and it is difficult to fix a color toner image. For this reason, a rubber roller is used as a pair of roller members, but the rubber roller has a low temperature rising speed, is not suitable for high-speed fixing, and a stable and uniform temperature distribution is not obtained, and fixing unevenness occurs. The problem of poor performance arises. In particular, high-speed fixation and fixability in fixing the surface toner image and fixing of the color toner image of the double-sided image forming apparatus are poor.

The present invention solves the above-mentioned problems on the rubber roller side to enable high-speed fixing while maintaining energy saving and warming-up performance, and to obtain good fixing performance at a uniform and stable temperature. Fixing device and image forming device, and in particular, enables high-speed fixing of surface toner images and color toner images in double-sided image formation while maintaining energy saving and warm-up performance, and good fixing performance due to uniform and stable temperature. It is an object of the present invention to provide a fixing device and an image forming apparatus capable of obtaining the following.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a film-like rotating member provided with a fixed heating element in contact therewith is provided. A cylindrical light-transmitting substrate having a heat-ray irradiating means for emitting heat rays, which is provided to face the film-shaped rotating member, and having a light-transmitting property with respect to the heat rays; A fixing device comprising a roll-shaped heat ray fixing rotating member provided with a translucent elastic layer on the outside and a heat ray absorbing layer on the outside of the translucent elastic layer to absorb the heat rays. 1 invention).

[0013] Further, the object is to provide an image forming apparatus for fixing and fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a film-shaped rotating member provided with a fixed heating element in contact therewith; A cylindrical light-transmissive base having heat-ray irradiating means for emitting heat rays, which is provided opposite to the film-shaped rotating member, and having a light-transmitting property with respect to the heat rays; A fixing device comprising a roll-shaped heat ray fixing rotating member provided with a light transmitting elastic layer and a heat ray absorbing layer for absorbing the heat rays outside the light transmitting elastic layer. This is achieved by a forming apparatus (a second invention).

[0014] It is another object of the present invention to provide an image forming apparatus for fixing and fixing a color toner image on a transfer material to the transfer material by heating and pressing, wherein the image forming apparatus includes a heat ray irradiating means for emitting heat rays therein. A cylindrical light-transmitting substrate having a light-transmitting property, a light-transmitting elastic layer outside the light-transmitting substrate, and a heat-ray absorbing layer absorbing the heat rays outside the light-transmitting elastic layer. A fixing device comprising a roll-shaped rotating member for heat ray fixing provided with a film-shaped rotating member provided so as to face the rotating member for fixing heat ray and having a fixed heating element inscribed therein; and This is achieved by an image forming apparatus (third invention) in which the heat ray fixing rotating member corresponds to a toner image.

The object of the present invention is to provide a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a film-shaped rotating member provided with an induction heating element in contact therewith; A cylindrical light-transmitting base having heat-ray irradiating means for emitting heat rays, which is provided to face the rotating member, and having a light-transmitting property with respect to the heat rays; and a light-transmitting outside of the light-transmitting base. A fixing device comprising: a roll-shaped rotating member for fixing a heat ray, provided with a transparent elastic layer and a heat ray absorbing layer for absorbing the heat ray outside the translucent elastic layer (fourth invention) Achieved by

[0016] Further, the object is to provide an image forming apparatus for fixing and fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a film-shaped rotating member provided with an induction heating element in contact therewith; A cylindrical light-transmissive base having heat-ray irradiating means for emitting heat rays, which is provided opposite to the film-shaped rotating member, and having a light-transmitting property with respect to the heat rays; A fixing device comprising a roll-shaped heat ray fixing rotating member provided with a light transmitting elastic layer and a heat ray absorbing layer for absorbing the heat rays outside the light transmitting elastic layer. This is achieved by a forming apparatus (a fifth invention).

The object is also to provide an image forming apparatus for fixing and fixing a color toner image on a transfer material to the transfer material by heating and pressurizing, wherein the image forming apparatus has a heat ray irradiating means for emitting heat rays therein, A cylindrical light-transmitting substrate having a light-transmitting property, a light-transmitting elastic layer outside the light-transmitting substrate, and a heat-ray absorbing layer absorbing the heat rays outside the light-transmitting elastic layer. A fixing device including a roll-shaped heat ray fixing rotating member provided with a film-shaped rotating member provided in contact with the heat ray fixing rotating member and provided with an induction heating element. This is achieved by an image forming apparatus (sixth invention) in which the heat ray fixing rotary member corresponds to a toner image.

Further, the above object is to provide a fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressing, wherein a fixing roller member made of a thin cylindrical elastic body;
A cylindrical light-transmitting base having heat-ray irradiating means for emitting heat rays, which is provided to face the fixing roller member, and having a light-transmitting property with respect to the heat rays; A fixing device comprising: a light-transmitting elastic layer; and a roll-shaped heat ray fixing rotating member provided with a heat ray absorbing layer for absorbing the heat rays outside the light transmitting elastic layer. Invention).

The above object is also achieved by an image forming apparatus for fixing and fixing a toner image on a transfer material to the transfer material by heating and pressing, wherein a fixing roller member comprising a thin cylindrical elastic body; Provided opposite to the roller member,
A cylindrical light-transmitting base having heat-ray irradiating means for emitting heat rays therein and having a light-transmitting property with respect to the heat rays; a light-transmitting elastic layer provided outside the light-transmitting base; This is achieved by an image forming apparatus (eighth invention) having a fixing device including a roll-shaped heat ray fixing rotating member provided with a heat ray absorbing layer for absorbing the heat rays outside the elastic layer. .

Further, the object is to provide an image forming apparatus for fixing and fixing a color toner image on a transfer material to the transfer material by heating and pressurizing, wherein the image forming apparatus has a heat ray irradiating means for emitting heat rays therein, A cylindrical light-transmitting substrate having a light-transmitting property, a light-transmitting elastic layer outside the light-transmitting substrate, and a heat-ray absorbing layer absorbing the heat rays outside the light-transmitting elastic layer. A heat-fixing rotary member in the form of a roll provided with a fixing device comprising a fixing roller member made of a thin cylindrical elastic body, provided opposite to the heat-ray fixing rotary member,
This is achieved by an image forming apparatus (ninth aspect) in which the heat ray fixing rotating member corresponds to the color toner image.

[0021]

Embodiments of the present invention will be described below. Note that the description in this column does not limit the technical scope of the claims and the meaning of terms. Further, the following assertive description in the embodiment of the present invention indicates the best mode, and does not limit the meaning or technical scope of the terms of the present invention. In the following description of each example of the fixing device and each example of the image forming apparatus, members having the same functions and structures are denoted by the same reference numerals.

Embodiment 1 FIGS. 1 to 8 show a first example of a fixing device according to the present invention and an image forming process and each mechanism of an embodiment of the first example of an image forming apparatus using the fixing device. It will be described using FIG. FIG. 1 is a first view of an image forming apparatus according to the present invention.
FIG. 2 is a cross-sectional configuration diagram of an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a toner image forming state in the image forming apparatus of FIG. 1, and FIG. FIG. 2B is a diagram illustrating a toner image formation state when the formed back image is transferred onto the intermediate transfer member. FIG. 2B illustrates a state in which the front image is formed on the image carrier in synchronization with the back image on the intermediate transfer member. FIG. 2C is a diagram showing a state of forming a toner image when performing a double-sided image formation on a transfer material, and FIG. 3 is a diagram showing a first example of a fixing device according to the present invention. FIG.
FIG. 4 is a detailed explanatory view of the fixing film, FIG. 5 is an enlarged cross-sectional configuration diagram of the roll-shaped hot-wire fixing rotating member of FIG. 3, and FIG. FIG. 7 is a diagram illustrating a concentration distribution of a heat ray absorbing layer of the member, FIG. 7 is a diagram illustrating an outer diameter and a thickness of a light-transmitting substrate of the roll-shaped heat ray fixing rotating member in FIG. 3, and FIG. FIG. 4 is a fixing control block diagram of the fixing device of FIG. 3 and fixing devices of the following respective examples.
In the following description of the embodiment of the image forming apparatus of the first example, in the transfer material supported and transported by the intermediate transfer body,
The surface facing the image carrier is referred to as the front surface, and the other surface, that is, the surface facing the intermediate transfer member is referred to as the back surface, and the image transferred to the front surface of the transfer material is transferred to the front image, the back surface of the transfer material. Image is called a back side image.

In FIG. 1, reference numeral 10 denotes a photosensitive drum as an image carrier, 11 denotes a scorotron charger as charging means for each color, 12 denotes an exposure optical system as image writing means for each color, and 13 denotes an exposure optical system for each color. A developing device 14a is an intermediate transfer belt which is an intermediate transfer member, and 14b is a device which transfers the toner image on the image carrier to the surface of the intermediate transfer member and the transfer material.
A primary transfer device as a secondary transfer device; 14g, a secondary transfer device as a secondary transfer device for transferring the toner image on the intermediate transfer member to the back surface of the transfer material; 150, a paper charger as a transfer material charging device;
14h is a transfer material static eliminator as a transfer material static elimination means, 160 is a separation claw 210 as a claw member and a spur 162 as a spur member.
The transport unit 170 having the following configuration is the fixing device of the first example.

The photosensitive drum 10, which is an image carrier, has a transparent conductive layer, a, on the outer periphery of a cylindrical substrate formed of a transparent member such as optical glass or transparent acrylic resin.
A photosensitive layer such as an Si layer or an organic photosensitive layer (OPC). The conductive layer is grounded, and the image bearing member driving motor (not shown) is driven in a clockwise direction indicated by an arrow in FIG. It is rotated at a linear speed of ４００400 mm / sec.

The toner image forming means for forming a toner image on the image carrier is a scorotron charger 11, which is a charging means.
It comprises a laser exposure optical system 120 as an image writing means and a developing device 13 as a developing means.

Scorotron charger 11 as charging means
Is a control grid maintained at a predetermined potential (unsigned)
And a discharge electrode 11a formed of, for example, a sawtooth electrode,
It is attached to face the photosensitive layer of the photosensitive drum 10 and is charged by corona discharge having the same polarity as the toner (in the present embodiment, the polarity of the toner used is set to minus polarity.
In the present embodiment, the scorotron charger 11 serving as a charging unit performs negative charging (to charge the photosensitive drum 10 uniformly). As the discharge electrode 11a, a wire electrode or a needle electrode may be used.

Laser exposure optical system 12 as image writing means
Reference numeral 0 denotes a semiconductor laser as a light emitting element (not shown), a rotary polygon mirror 120b for rotating and scanning a laser beam emitted from the semiconductor laser, an fθ lens 120c, and a reflection mirror 12
The laser beam emitted from the semiconductor laser is rotationally scanned by a rotating polygon mirror 120b, and is read by a separate image reading device onto the rotating photosensitive drum 10 via an fθ lens 120c and a reflecting mirror 120d. Then, an image is written on the photosensitive layer of the photosensitive drum 10 according to the image data stored in the memory, and an electrostatic latent image is formed on the photosensitive drum 10. It is necessary to change the image data so that the image data corresponding to the front image and the image data corresponding to the back image are mirror images of each other.

The developing device 13 as a developing means keeps a predetermined gap with respect to the peripheral surface of the photosensitive drum 10 and rotates in a forward direction with respect to the rotating direction of the photosensitive drum 10 at a developing position. A developing sleeve 13a formed of a cylindrical nonmagnetic stainless steel or aluminum material having an outer diameter of 15 to 25 mm, and a one-component or two-component developer of black (K) is accommodated inside the developing device 13 are doing. The developing sleeve 13a of the developing device 13 is provided with a predetermined gap, for example, 100 to
The developer on the developing sleeve 13a having a layer thickness of 80 to 300 μm is kept out of contact with the photosensitive drum 10 with a gap of 500 μm, and a developing bias in which a DC voltage and an AC voltage are superimposed is applied to the developing sleeve 13a. As a result, non-contact reversal development is performed, and a toner image is formed on the photosensitive drum 10.

An intermediate transfer belt 14a as an intermediate transfer member
Preferably has a volume resistivity of 10 ⁹ Ω · cm or more,
It is an endless belt of less than ¹² Ωcm, for example, a modified polyimide, a thermosetting polyimide, an ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, a thickness of 0.1 to 0.1 in which a conductive material is dispersed in an engineering plastic such as nylon alloy. It is a seamless belt having a two-layer structure in which a 1.0 mm semiconductive film substrate is coated with a fluorine coating having a thickness of 5 to 50 μm, preferably as a toner filming preventing layer. In addition, as the base of the intermediate transfer belt 14a, a semiconductive rubber belt having a thickness of 0.5 to 2.0 mm in which a conductive material is dispersed in silicon rubber or urethane rubber or the like can be used. The intermediate transfer belt 14a includes a driving roller 1 that is a roller member.
4d, the secondary transfer opposing roller 14j, the driven roller 14e, and the tension roller 14i, and are rotated counterclockwise as indicated by the arrow in FIG. The driven roller 14e, the secondary transfer opposing roller 14j, and the driving roller 14d are rotated at a fixed position, and the tension roller 14i is movably supported and rotated by an elastic force such as a spring (not shown). Drive roller 1 is driven by an intermediate transfer member drive motor (not shown).
4d is rotated to drive and rotate the intermediate transfer belt 14a. The rotation of the intermediate transfer belt 14a causes the secondary transfer opposing roller 14j, the driven roller 14e, and the tension roller 14i to be driven and rotated. The slack of the rotating intermediate transfer belt 14a is tensioned by the tension roller 14i. The intermediate transfer belt 14a is driven by a driven roller 14e.
The recording paper P as a transfer material is supplied to a position where
It is supported and transported by the intermediate transfer belt 14a. The recording paper P is separated from the intermediate transfer belt 14a at a curvature portion KT at an end of the intermediate transfer belt 14a stretched around the driving roller 14d on the fixing device 170 side.

A primary transfer device 14b as a primary transfer means for transferring the toner image on the image carrier to the surface of the intermediate transfer member or the transfer material is opposed to the photosensitive drum 10 with the intermediate transfer belt 14a interposed therebetween. The corona discharger is provided, and forms a transfer area (no reference numeral) between the intermediate transfer belt 14a and the photosensitive drum 10. A DC voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied to the primary transfer device 14b, and the toner image on the photosensitive drum 10 is transferred onto the intermediate transfer belt 14a or the recording paper P as a transfer material. Transfer to the surface. As the primary transfer device 14b, a transfer roller or a transfer blade can be used in addition to the corona discharge device.

A secondary transfer device 14g, which is a secondary transfer means for retransferring the toner image on the intermediate transfer member to the back surface of the transfer material, is constituted by a corona discharger, and is provided between the primary transfer device 14b and the driving roller 14d. And is provided to face the secondary transfer facing roller 14j that is grounded with the intermediate transfer belt 14a interposed therebetween.
Polarity opposite to toner (positive polarity in this embodiment)
Is applied to transfer the toner image on the intermediate transfer belt 14a to the back surface of the recording paper P.

The paper charger 150, which is a transfer material charging means, is preferably constituted by a corona discharger, is provided opposite to a driven roller 14e which is grounded with the intermediate transfer belt 14a interposed, and has the same polarity as the toner (this embodiment). (In the embodiment, negative polarity) is applied, and the recording paper P is charged and attracted to the intermediate transfer belt 14a. As the paper charger 150, in addition to the corona discharger, a paper charging brush or a paper charging roller capable of abutting and releasing the saw-toothed electrode and the intermediate transfer belt 14a may be used.

Transfer material static eliminator 14h as transfer material static elimination means
Is a driving roller which is preferably constituted by a corona discharger, and is grounded with the intermediate transfer belt 14a interposed therebetween near the position where the recording paper P is separated from the intermediate transfer belt 14a at the end of the intermediate transfer belt 14a on the fixing device 170 side. An AC voltage superimposed with a DC voltage for preventing separation discharge at the time of separation of the surface toner image having a high charge amount (Q / M) charged by the secondary transfer device 14g and applied to the secondary transfer device 14g; The recording paper P conveyed by the intermediate transfer belt 14a is discharged and separated from the intermediate transfer belt 14a.

The transport section 160 has a separation claw 210 as a transfer material separation assisting means and a spur 162 as a spur member.
The intermediate transfer belt 14a is provided between the curvature section KT at the end of the fixing device 170 side and the fixing device 170 of the first example. The transport unit 160 is heated by the heat from the fixing device 170.
If the intermediate transfer belt 14a is deformed or the intermediate transfer belt 1
This prevents the toner image carried on the transfer belt 4a from becoming slightly fused and difficult to transfer, and prevents the toner from being fixed on the intermediate transfer belt 14a.

The separation claw 210, which is a transfer material separation assisting means, is close to the curvature portion KT of the intermediate transfer belt 14a, and has a predetermined distance from the intermediate transfer belt 14a, preferably 0.1 to 2.0.
When the recording paper P is separated from the intermediate transfer belt 14a, the recording paper P is bent toward the intermediate transfer belt 14a to be conveyed when the recording paper P is separated from the intermediate transfer belt 14a. To assist the curvature separation of the recording paper P.

The spur 162, which is a spur member, has a plurality of protrusions 162a on its peripheral surface, and is provided rotatably about a rotation support shaft 165. The spur 162 guides the back side of the recording sheet P to convey the recording sheet P, prevents the back side toner image of the recording sheet P having the toner image on both sides from being disturbed, and also supplies the recording sheet P to the fixing device 170. The recording paper P is stably conveyed to the fixing device 170 while keeping the entering direction constant.

The separation claw 210 and the spur 162 are disposed on the side opposite to the photosensitive drum 10 with respect to the transfer material conveying surface on the intermediate transfer belt 14a or its extension surface.
It is also possible to provide spurs 162 as spur members on both sides of the transfer material conveying surface or an extension surface thereof.

The fixing device 170 according to the first embodiment includes a ceramic heater 172 as a fixed heating element, and a heat fixing film as a film-shaped rotating member for fixing a toner image of an upper surface (front surface side). 17A, and a lower heat roller 17 serving as a lower roll-shaped heat ray fixing rotating member for fixing a toner image of a lower side (rear side image).
The heat-ray fixing roller 17a is driven to rotate by a fixing drive motor (not shown), and the heat fixing film 17A is driven to rotate. A halogen lamp 171g or a xenon lamp (not shown) that emits a heat ray such as an infrared ray or a far-infrared ray including visible light depending on a light source is disposed as a heat ray irradiating means in the center of the heat ray fixing roller 17a. Heat fixing film 17A and heat ray fixing roller 17a
The recording paper P is sandwiched by a nip portion N formed between
By applying heat and pressure, the toner image on the recording paper P is fixed.

Next, the image forming process will be described.

The photosensitive drum 10 is rotated clockwise as indicated by the arrow in FIG. The application of the potential is started.

After a potential is applied to the photosensitive drum 10, image writing by an electric signal corresponding to image data is started by the laser exposure optical system 120, and the surface of the photosensitive drum 10 corresponds to an original image. An electrostatic latent image is formed.

The electrostatic latent image is reversely developed by the developing device 13 in a non-contact state, and a toner image is formed on the photosensitive drum 10 (toner image forming means).

The toner image serving as the back surface image formed on the photosensitive drum 10 as the image carrier by the above-described image forming process is transferred to the intermediate transfer member by the primary transfer device 14b in the transfer area (no symbol). A certain intermediate transfer belt 14
(a) of FIG. 2 (FIG. 2 (A)).

After the toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is subjected to static elimination by the photosensitive drum AC static eliminator 16, the toner is transferred to a cleaning device 19 serving as an image carrier cleaning means, Is cleaned by a cleaning blade 19a made of a rubber material, and is collected by a screw 19b in a toner discharge container (not shown).

After the toner image serving as the back surface image is formed on the intermediate transfer belt 14a as described above, the toner image serving as the front surface image is continuously formed on the photosensitive drum 10 in the same manner as the above-described image forming process. Is formed (see FIG. 2).
(B)). At this time, the image data is changed so that the front surface image formed on the photosensitive drum 10 is a mirror image of the rear surface image formed on the photosensitive drum 10.

With the formation of a surface image on the photosensitive drum 10, recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a feed roller 15a, and is used as a transfer material feeding means. Timing roller 1
The toner image of the front surface image formed on the photosensitive drum 10 and the toner image of the back surface image carried on the intermediate transfer belt 14a are transferred in synchronization by the driving of the timing roller 15b. Area (unsigned). At this time, the fed recording paper P is transferred to a paper charger 15 serving as a transfer material charging unit provided on the front side of the recording paper P.
0, the intermediate transfer belt 1 is charged to the same polarity as the toner.
4a, and is conveyed to the transfer area (no symbol). By charging the paper with the same polarity as the toner, the toner image is prevented from being attracted to the toner image on the intermediate transfer belt 14a and the toner image on the photosensitive drum 10, thereby preventing the toner image from being disturbed.

In the transfer area (no sign), the surface image on the photosensitive drum 10 is applied to the surface of the recording paper P by the primary transfer device 14b to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied. Transcribed. At this time, the back surface image on the intermediate transfer belt 14a is not transferred to the recording paper P but exists on the intermediate transfer belt 14a.

The recording paper P on which the toner image has been transferred is
Polarity opposite to toner (positive polarity in this embodiment)
Is transferred to the secondary transfer device 14g to which the voltage of
The backside image on the peripheral surface of the intermediate transfer belt 14a is retransferred to the backside of the recording paper P by the next transfer unit 14g (FIG. 2).
(C)).

The recording paper P having the toner images formed on both sides is
The curvature of the curvature portion KT of the intermediate transfer belt 14a, the charge removal operation by the transfer material charge remover 14h as the transfer material charge removal means provided at the end of the intermediate transfer belt 14a, and the conveyance with a predetermined interval from the intermediate transfer belt 14a The separation claw 210 provided in the section 160 separates the intermediate transfer belt 14a from the intermediate transfer belt 14a, is conveyed to the fixing device 170 through a spur 162 provided in the conveyance section 160, and is provided between the heat fixing film 17A and the heat ray fixing roller 17a. The toner image on the recording paper P is fixed by being conveyed between the nip portions N and subjected to heat and pressure in the nip portion N. The recording paper P on which double-sided image recording has been performed is sent upside down, and is discharged by a discharge roller 18 to a tray outside the apparatus.

The toner remaining on the peripheral surface of the intermediate transfer belt 14a after the transfer is provided to face the driven roller 14e with the intermediate transfer belt 14a interposed therebetween, and is applied to the intermediate transfer belt 14a with the support shaft 142 as a rotation fulcrum. The intermediate transfer member is cleaned by an intermediate transfer member cleaning device 140 which is an intermediate transfer member cleaning unit having an intermediate transfer member cleaning blade 141 capable of contacting and releasing contact.

Further, the toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is subjected to static elimination by the photosensitive drum AC static eliminator 16 and then cleaned by the cleaning device 19 to be cleaned in the next image forming cycle. Yes.

As shown in FIG. 3, the fixing device 1 of the first example
Reference numeral 70 denotes a heat fixing film 17 as a film-like rotating member for fixing a toner image of an upper side (front side) surface image.
A, and a heat-fixing roller 17a as a lower roll-shaped heat-ray fixing rotating member for fixing a toner image of a lower (back-side) rear image, and a heat-fixing film 17A as a hard roller And the heat ray fixing roller 17a as a soft roller having elasticity,
A wide nip portion N having a width of 30 mm or less, preferably 10 mm or more, sandwiches the recording paper P that enters the nip portion N and passes through the nip portion N, and applies heat and pressure to the toner on the recording paper P. Fix the image.

The heat fixing film 17A for fixing the toner image of the surface image is, for example, a thin fixing film 171 having a thickness of 40 to 100 μm, a ceramic heater 172 as a fixed heating element, and a heater holder for holding the ceramic heater 172. 173 as a hard roller. In addition, it is preferable that a metal roller member having good thermal conductivity such as an aluminum material or a stainless steel material or a heat equalizing roller TR4 using a heat pipe be provided inside the heater holder 173. Thus, the heat generation temperature distribution in the axial direction of the heat fixing film 17A heated by the ceramic heater 172 is made uniform. TS2 is a temperature sensor mounted on the back surface of the ceramic heater 172 of the upper heat fixing film 17A and serving as a temperature detecting unit using, for example, a contact-type thermistor for performing temperature control. As the temperature sensor TS2, a non-contact type sensor can be used in addition to a contact type sensor.

The heat capacity of the fixing film 171 is about 1/20 of that of the heat ray fixing roller 17a, and a quick start with almost zero warm-up is possible. The heater holder 173 holds the rotating fixing film 17.
1, while being pressed against the heat ray fixing roller 17a via a ceramic heater 172 to be held. The fixing film 171 has a heater holder 173.
The heat ray fixing roller 17 loosely fits into the
The rotation is driven by the surface frictional force a. Heat fixing film 1
Since 7A has a small heat capacity, the heat of the heat ray fixing roller 17a is hardly removed.

As the ceramic heater 172, an alumina substrate provided with a resistor and overcoat glass by thick film printing is used, and the thermal resistance between the fixing film 171 is lower than that of the fixed heating element.

As shown in FIG. 4, the structure of the fixing film 171 includes a base material 171A, a conductive layer 171B, and a surface release layer 171C.

As the base material 171A, a polyimide resin having excellent strength and dimensional stability at high temperatures is preferable, and the thickness is preferably as thick as about 40 to 100 μm. By increasing the thickness to about 40 μm, the strength and rigidity are increased, and the end of the fixing film 171 during rotation can be regulated without buckling. On the other hand, if the thickness is more than 100 μm, the heat conduction becomes poor, and the heat conduction becomes large, so that it becomes difficult to heat up instantaneously and the electric power used increases. In order to prevent offset, it is preferable to provide a surface release layer 171C, for example, a layer of fluororesin (PFA or PTFE), and furthermore, between the inner surface of the base material 171A of the fixing film 171 and the surface of the ceramic heater 172. The conductive layer 171B is provided and grounded in order to eliminate the influence of the triboelectric charge generated by the sliding of the contact. Also, the surface release layer 171 is formed so as to release the charged charges separated from the rear end of the recording paper P in a low humidity environment.
An offset is prevented by lowering the resistance by inserting a conductive filler in C. However, if the resistance value is too low, the transfer charge leaks to cause an offset, so that 2 × 10 ^{10 to} 5 × 10 ¹¹
A resistance value of Ω / cm ² is preferred.

The heat ray fixing roller 17a as a heat ray fixing rotating member for fixing the toner image on the back surface has a cylindrical light transmitting base 171a and a light transmitting outside (outer peripheral surface) of the light transmitting base 171a. Elastic layer 171d and heat ray absorbing layer 171
b and a release layer 171c are provided as a soft roller in that order. A halogen lamp 171g, which is a heat ray irradiating means for emitting heat rays such as infrared rays or far infrared rays including visible light depending on a light source, is provided in the center of the inside of the light transmitting substrate 171a.
And a xenon lamp (not shown). The heat ray fixing roller 17a as a heat ray fixing rotating member is configured as a highly elastic soft roller as described later. A heat ray emitted from the halogen lamp 171g or a xenon lamp (not shown) is absorbed by the heat ray absorbing layer 171b to form a roll-shaped heat ray fixing rotating member capable of rapid heating. It is preferable that a heat equalizing roller TR4 be provided on the surface of the heat ray fixing roller 17a. The heat generation temperature distribution on the peripheral surface of the heat ray fixing roller 17a heated by the heat ray absorption layer 171b is made uniform. Heat uniformizing roller TR
4, uniformity of the temperature unevenness in the vertical and horizontal directions of the heat ray fixing roller 17a caused by the passage of the transfer material is made uniform. TS1 is a temperature sensor attached to the lower heat ray fixing roller 17a, which is a temperature sensor using a contact type thermistor for performing temperature control. As the temperature sensor TS1, a non-contact type sensor can be used in addition to a contact type sensor.

The temperature control of the upper heat fixing film 17A and the lower heat ray fixing roller 17a is performed as shown in FIG.
Heat fixing film 17 as upper film-shaped rotating member
A heat fixing film 1 by a temperature sensor TS2 as a temperature detecting means for detecting the temperature of the ceramic heater 172 of A
7A (T2 (° C.)) and the temperature (T1 (° C.)) of the heat ray fixing roller 17a by the temperature sensor TS1 as a temperature detecting means for detecting the temperature of the heat ray fixing roller 17a as a lower heat ray fixing rotating member. ), And the ceramic heater 172 and the ceramic heater 172 from the reference table corresponding to the temperature (detection temperature) T2 and the temperature (detection temperature) T1 stored in advance in the ROM of the storage unit (ROM, RAM) as a reference table The on-off time of the halogen lamp 171g or the xenon lamp (not shown) is referred to through the fixing control unit, and the temperature of the upper heat fixing film 17A and the lower heat ray fixing roller 17a is controlled. In particular, in both-side fixing, since the temperatures of both the upper heat fixing film 17A and the lower heat ray fixing roller 17a affect the fixing,
It is necessary to control the temperatures of both the upper heat fixing film 17A and the lower heat ray fixing roller 17a.

A flat nip portion N is formed between the upper hard roller and the lower soft roller having high elasticity, following the bottom shape of the heater holder 173 of the upper heat fixing film 17A. Fixing is performed.

Ceramic heater 17 as fixed heating element
2 and the heat generated by the heat rays of the halogen lamp 171g and the xenon lamp (not shown) in the heat ray absorbing layer 171b.
Although instantaneous heating is difficult due to the heating of 7a, a fixing device capable of energy saving and quick start (rapid heating) with a short warm-up time can be realized.

According to FIG. 5, the configuration of the heat ray fixing roller 17a is, as shown in the cross section in FIG. 5 (a), a thickness of 1 to 20 mm, preferably 2 to 20 mm for the cylindrical translucent substrate 171a. Pyrex glass, sapphire (Al) that is 5 mm thick and transmits heat rays such as infrared rays or far infrared rays from a halogen lamp 171 g or a xenon lamp (not shown)
Ceramic materials such as ₂ O ₃ ) and CaF ₂ (thermal conductivity is (5 to 5)
20) × 10 ⁻³ J / cm · s · K, specific heat of (0.5 to
2.0) × J / g · K, specific gravity of 1.5 to 3.0), and a light-transmitting resin using polyimide, polyamide, or the like (thermal conductivity of (2 to 4) × 10 ⁻ ). ³ J / cm · s
・ K, specific heat (1-2) × J / g ・ K, specific gravity 0.8-
1.2) can also be used. For example, as the translucent substrate 171a of the heat ray fixing roller 17a, the inner diameter is 32 m.
Pyrex glass having an outer diameter of 40 mm and a layer thickness (thickness) of 4 mm (specific heat: 0.78 J / g · K, specific gravity: 2.3
The heat capacity Q1 per A-3 size width (297 mm) of the translucent substrate 171a when using 2) is about 60 cal.
/ Deg. The wavelength of the heat ray passing through the translucent substrate 171a is 0.1 to 20 μm, preferably 0.3 to 20 μm.
Since the particle size is 3 μm, an adjuster for hardness and thermal conductivity is added as a filler, but the average particle size including primary and secondary particles having a particle size of ２, preferably １ ／ or less, of the wavelength of the heat ray is added. ITO, titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, carbonic acid having a heat ray transmission of 1 μm or less, preferably 0.1 μm or less (in some cases, transmission of infrared or far infrared rays including visible light depending on the light source). The translucent substrate 171a may be formed by dispersing fine particles of a metal oxide such as calcium in a resin binder. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. As mentioned above,
The translucent substrate 171a does not have good thermal conductivity.

The light-transmitting elastic layer 171d has a thickness of 0.5 to 2
It is formed of a rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light or infrared rays depending on the light source) using, for example, silicon rubber or fluorine rubber having a thickness of 0 mm, preferably 1 to 5 mm. . Translucent elastic layer 171d
In order to respond to high speed, a method of improving thermal conductivity by mixing a metal oxide powder such as silica, alumina or magnesium oxide as a filler into a base layer (silicone rubber or fluorine rubber) has been adopted. Conductivity (1-3)
× 10 ⁻³ J / cm · s · K, specific heat of (1-2) × J / g
-Use a rubber layer having a K and a specific gravity of 0.9 to 1.0. For example, as the translucent elastic layer 171d of the heat ray fixing roller 17a,
A-3 size width of the light-transmitting elastic layer 171d when silicon rubber having an outer diameter of 50 mm and a layer thickness (thickness) of 5 mm (specific heat is 1.1 J / g · K, specific gravity is 0.91) is used ( 297
The heat capacity Q2 per mm) is about 50 cal / deg. The rubber layer is made of a light-transmitting substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J / cm · s ·
Since it is an order of magnitude lower than K), it functions as a layer having heat insulating properties.
When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a hardness of 40 Hs usually has a hardness of 60 Hs (JIS,
A rubber hardness). Preferred rubber hardness is 5 to 60 Hs. Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is coated with a fluorine-based rubber having a thickness of 20 to 300 μm as an oil-resistant layer to prevent oil swelling. As the silicon rubber of the top layer of the translucent elastic layer 171d, HTV (High Temp) is used.
RTV (RoomTemperature V) which has better releasability than ETERNUS
olcanizing) and LTV (Low Tempe)
(ratio volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, the wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm, and preferably 0.3 to 3 μm. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less including primary and secondary particles,
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
71d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 1 as a heat ray fixing rotating member is provided.
7a is configured as a highly elastic soft roller.

The heat ray absorbing layer 171b is formed of the remaining heat rays emitted from a halogen lamp 171g or a xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d. 90 to 100%, preferably 95 to 100% of the heat rays, which are about 100% of the heat rays transmitted through the 171a and the translucent elastic layer 171d, are absorbed by the heat ray absorbing layer 171b to form a heat ray fixing rotating member capable of instantaneous heating. As described above, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F
e ₂ O ₃ ) or the like, and a heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm is sprayed on the outer side (outer peripheral surface) of the light transmitting elastic layer 171 d. It is formed by coating or the like. Heat ray absorbing layer 171
b has a thermal conductivity of the rubber layer of the translucent elastic layer 171d (having a thermal conductivity of (1-3) × 10 ⁻³ J / cm · s · K and a specific heat of (1-2) × J / g · K, specific gravity is 0.9 to 1.0), and a slightly higher (3 to 10) × 10 ⁻³ J / cm · s · K (specific heat is increased by adding an absorbent such as carbon black). 2.0) × J / g · K, and the specific gravity can be set to (〜0.9). As the heat ray absorbing layer 171b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%,
For example, if it is about 20 to 80%, the heat rays leak, and when the heat ray fixing roller 17a as a heat ray fixing rotating member is used for monochrome image formation due to the leaked heat rays, a specific position of the heat ray fixing roller 17a is determined by filming or the like. When the black toner adheres to the surface of the device, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of the heat rays is further superimposed on the portion to damage the heat ray absorbing layer 171b. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The heat rays transmitted through the heat ray absorbing layer 171
The heat ray absorption rate of the heat ray absorption layer 171b is set to 90 to 100%, which is about 100%, and preferably 95 to 100% so that the heat ray is completely absorbed by b. When the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate due to the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b may be damaged by local heating by the thin film and the strength may be insufficient. If the thickness of the heat ray absorbing layer 171b exceeds 500 μm and is too thick, poor heat conduction or large heat capacity makes rapid heating difficult. By setting the heat ray absorption rate of the heat ray absorption layer 171b to 90 to 100%, which is about 100%, preferably 95 to 100%, or setting the thickness of the heat ray absorption layer 171b to 10 to 500 μm, preferably 20 to 100 μm, Local heat generation in the absorption layer 171b is prevented, and uniform heat generation is performed. Heat ray absorbing layer 1
Since the wavelength of the heat ray projected on 71b is 0.1 to 20 μm, and preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler. / 2, preferably 1/5 or less, including primary and secondary particles, having an average particle size of 1 μm or less, preferably 0.1 μm
Fine particles of metal oxides such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, calcium carbonate, etc. having the following heat ray transmittance (infrared ray or visible ray including visible light depending on the light source) are used as the resin binder. The heat ray absorbing layer 171b may be formed by dispersing 5 to 50% by weight. Thus, the heat ray absorbing layer 171b
Since the heat capacity is reduced so that the temperature rises immediately, the heat ray fixing roller 17a as a heat ray fixing rotating member is used.
This prevents the problem that the temperature is lowered and the fixing unevenness occurs. As the heat ray absorbing layer 171b, carbon black, graphite,
A mixture of iron black (Fe ₃ O ₄ ), various ferrites and their compounds, and powders such as copper oxide, cobalt oxide, and red iron oxide (Fe ₂ O ₃ ) may be used. For example, heat ray fixing roller 1
7a of the heat ray absorbing layer 171b (or the dual-purpose layer 17 described later).
As 1Z), a fluororesin (specific heat: 2.0 J / g · K, specific gravity: 0.9) having a layer thickness (thickness) of 50 μm is applied to the surface (outer peripheral surface) of the light-transmitting elastic layer 171 d having an outer diameter of 50 mm. A of heat ray absorbing layer 171b (or dual-purpose layer 171Z) when used
The heat capacity Q3 per −3 size width (297 mm) is about 1.0 cal / deg. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

Further, a PFA (fluororesin) tube having a thickness of 30 to 100 μm is coated on the outer side (outer peripheral surface) of the heat ray absorbing layer 171b separately from the heat ray absorbing layer 171b in order to improve the releasability from the toner. Or fluorinated resin (PF
A or PTFE) Release layer 171c coated with a paint of 20 to 30 μm (having a thermal conductivity of (1 to 10) × 10 ⁻³ J / cm.
S · K, specific heat (（2.0) × J / g · K, specific gravity (〜0.9)) (separated type).

Further, as shown in cross section in FIG. 5B, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (Fe ₂ O ₃ ), etc. Heat-absorbing member mixed with powder of PTFE, and a fluororesin (PFA or PT) that also serves as a binder and a release agent
FE) paint is mixed and mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG.
A heat-fixing rotary member in the form of a roll having elasticity may be formed outside (outer peripheral surface) of the translucent elastic layer 171d formed outside (outer peripheral surface). The thermal conductivity of the dual-purpose layer 171Z is substantially the same as the thermal conductivity of the heat ray absorbing layer 171b.
(3-10) × 10 ⁻³ J / cm · s · K (specific heat
2.0) × J / g · K, and specific gravity is (０．９0.9).
As described above, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the translucent base 171a and the translucent elastic layer 171d are:
In order to completely absorb the heat rays transmitted through the light-transmitting base 171a and the light-transmitting elastic layer 171d, the heat ray absorptivity of the dual-purpose layer 171Z is set to 90 to 100%, which is about 100%, and preferably 95 to 100%. When the heat ray absorptivity in the dual-purpose layer 171Z is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the heat ray fixing rotating member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the heat ray fixing rotating member at a specific position due to, for example, mining, heat is generated from the adhering portion by the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the dual-purpose layer 171Z. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The combined layer 171Z has a heat ray absorptivity of about 100%, which is about 90-100%, preferably 95-1%, so that the heat rays transmitted through the heat ray fixing rotary member are completely absorbed in the heat ray fixing rotating member.
00%. Further, local heat generation in the dual-purpose layer 171Z is also prevented, and uniform heat generation is performed. In addition, the combined use layer 17
Since the wavelength of the heat ray projected on 1Z is 0.1 to 20 μm, preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler, but the particle size is 1 to the wavelength of the heat ray. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less, preferably 0.1 μm or less including primary and secondary particles (infrared ray or visible ray including visible light depending on the light source). The dual-purpose layer 171Z may be formed by dispersing fine particles of a metal oxide such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder.

According to FIG. 6, the heat ray absorbing layer 171 of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is used.
If the above-mentioned concentration distribution of the heat ray absorbing member is provided uniformly in b, heat is concentrated in the heat ray absorbing layer 171b at the boundary, and the heat easily flows to the light transmitting elastic layer 171d side. It is preferable to generate heat inside the heat ray absorbing layer 171b by using a member having a lower thermal conductivity than 171a or by providing a concentration distribution from the viewpoint of dispersing the heat generation distribution. As shown in the graph (a), the concentration distribution of the heat ray absorbing layer 171b is such that the interface on the side of the transparent elastic layer 171d which is in contact with it has a low concentration, is gradually inclined toward the outer peripheral surface, and is gradually increased. (For the thickness t1 of the heat ray absorbing layer 171b,
At a position of about 2/3 to 4/5 from the side of the light-transmitting elastic layer 171d), the concentration is set so as to be 100% absorbed and saturated. Thereby, the heat generation distribution due to the absorption of the heat ray in the heat ray absorption layer 171b is as shown in the graph (b).
It is formed in a parabolic shape having a maximum value near the center of the heat ray absorbing layer 171b and a minimum value near the interface and the outer peripheral surface of the heat ray absorbing layer 171b. Alternatively, a light-transmitting heat-resistant resin (polyimide, fluororesin, or silicone resin) having a thickness of 10 to 500 μm, preferably 2
It is preferable to provide 0 to 100 μm. Further, it is preferable to suppress heat loss as a member having a lower thermal conductivity than the translucent substrate 171a. This reduces heat generation due to absorption of heat rays at the interface, prevents heat from flowing out, and prevents damage to the adhesive layer and heat ray absorbing layer 171b at the interface. Also, before the outer peripheral surface side (2/3 to 4/5 of the thickness t1 of the heat ray absorbing layer 171b from the transparent substrate 171a side).
(Position of degree) to the outer peripheral surface so as to saturate the concentration distribution. In particular, even when the dual-purpose layer 171Z is used, there is no influence even if the outer peripheral surface layer is shaved. Note that a saturated layer may be formed as shown by a dotted line. In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle.

As shown in FIG. 7, the outer diameter φ of the cylindrical light-transmitting substrate 171a of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is 15 to 60 mm.
As the thickness t, a thicker one is better in terms of strength and a thinner one is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the outer diameter of the cylindrical translucent substrate 171a is The relationship between φ and the thickness t is 0.02 ≦ t / φ ≦ 0.20, and preferably 0.04 ≦ t / φ ≦ 0.10. When the outer diameter φ of the transparent substrate 171a is 40 mm, the thickness t of the transparent substrate 171a is 0.8 mm ≦ t ≦ 8 m.
m, preferably 1.6 mm ≦ t ≦ 4.0 mm. When t / φ is less than 0.02 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.20, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, depending on the material, a light-transmitting substrate may absorb about 1 to 20% of heat rays, and it is preferable that the substrate be thin as long as the strength can be maintained.

As described above, by using the fixing device 170 of the first example described with reference to FIG. 3, the upper heat fixing film is disposed between the upper hard roller and the lower elastic roller. A flat nip N is formed following the shape of the bottom surface of the heater holder 173 of the heater 17A to fix the toner image. Heating in the heat absorbing layer 171b by the heat rays (not shown) enables fixing at high speed while saving energy and shortening the warm-up time, and also provides a fixing device and an image that can obtain a good fixing property with a uniform and stable temperature. A forming apparatus becomes possible. In particular, in the double-sided image forming apparatus described with reference to FIG. 1, high-speed fixing of the surface toner image in the double-sided image formation is achieved while saving energy and shortening the warm-up time, and a good surface toner image is formed by a uniform and stable temperature. Can be fixed.

Embodiment 2 A second example of the fixing device according to the present invention and an image forming process and each mechanism of the second embodiment of the image forming apparatus using the fixing device will be described with reference to FIGS. A description will be given with reference to FIGS. FIG. 9 is a cross-sectional configuration diagram of a color image forming apparatus showing an embodiment of a second example of the image forming apparatus according to the present invention, and FIG.
FIG. 11 is a side sectional view of the image carrier of FIG. 9, and FIG. 11 is a sectional configuration view of a second example of the fixing device according to the present invention.

According to FIG. 9 or FIG. 10, the photosensitive drum 10 as an image carrier is provided on the outer periphery of a cylindrical base formed of a light-transmitting member such as glass or light-transmitting acrylic resin. It is formed by forming a photoconductive layer and a photoconductor layer of an organic photosensitive layer (OPC).

The photosensitive drum 10 is rotated clockwise as shown by an arrow in FIG. 9 in a state where the light-transmitting conductive layer is grounded by power from a driving source (not shown).

In the present invention, the exposure beam for image exposure is:
The photoconductor layer of the photoconductor drum 10, which is the image forming point, only needs to have an exposure light amount of a wavelength that can provide an appropriate contrast with respect to the light attenuation characteristic (photocarrier generation) of the photoconductor layer. . Therefore, the light transmittance of the light-transmitting substrate of the photosensitive drum 10 in the present embodiment does not need to be 100%, and may have a characteristic of absorbing a certain amount of light when transmitting the exposure beam. Good. The point is that any suitable contrast can be provided. As a material of the light-transmitting substrate, an acrylic resin, particularly one obtained by polymerizing a methyl methacrylate monomer, is preferably used because of its excellent light-transmitting properties, strength, accuracy, surface properties, etc. Various translucent resins such as acryl, fluorine, polyester, polycarbonate, polyethylene terephthalate and the like used for the above can be used. Further, as long as it has a light-transmitting property with respect to the exposure light, it may be colored. As the light-transmitting conductive layer, indium tin oxide (I
TO), tin oxide, lead oxide, indium oxide, copper iodide, or a metal thin film of Au, Ag, Ni, Al, or the like that maintains light transmissivity. Reactive deposition method, various sputtering methods, various CV
D method, dip coating method, spray coating method and the like can be used.
Various organic photosensitive layers (OPC) can be used as the photoconductor layer.

The organic photosensitive layer serving as the photosensitive layer of the photoconductor layer includes a charge generation layer (CGL) mainly composed of a charge generation substance (CGM) and a charge transport layer (CTM) mainly composed of a charge transport substance (CTM). And CTL). An organic photosensitive layer having a two-layer structure has high durability as an organic photosensitive layer due to its thick CTL and is suitable for the present invention.
The organic photosensitive layer may have a single layer structure containing a charge generation material (CGM) and a charge transport material (CTM) in one layer. ,
Usually, a binder resin is contained.

A scorotron charger 11 as a charging unit described below, and an exposure optical system 1 as an image writing unit will be described.
2. The developing device 13 as a developing unit is prepared for an image forming process for each color of yellow (Y), magenta (M), cyan (C) and black (K), respectively. Are arranged in the order of Y, M, C, and K with respect to the rotation direction of the photosensitive drum 10 indicated by the arrow in FIG.

Scorotron charger 11 as charging means
Is mounted so as to face and be close to the photosensitive drum 10 in a direction (perpendicular to the plane of FIG. 9) orthogonal to the moving direction of the photosensitive drum 10 as an image forming body. A control grid (unsigned) maintained at a predetermined potential with respect to the layer and a corona discharge electrode 11a
For example, using a saw-tooth electrode, a charging action (in the present embodiment, negative charging) is performed by corona discharge having the same polarity as the toner, and a uniform potential is applied to the photosensitive drum 10. As the corona discharge electrode 11a, a wire electrode or a needle electrode may be used.

The exposure optical system 12 for each color is a linear exposure element (LED) in which a plurality of LEDs (light emitting diodes) as light emitting elements for image exposure light are arranged in an array parallel to the axis of the photosensitive drum 10. (Not shown) and a selfoc lens (not shown) as an equal-magnification imaging element are configured as an exposure unit attached to a holder. Cylindrical holding member 2
At 0, the exposure optical system 12 for each color is attached and housed inside the base of the photosensitive drum 10. In addition, as the exposure element, a linear element in which a plurality of light emitting elements such as FL (phosphor emission), EL (electroluminescence), and PL (plasma discharge) are arranged in an array is used.

The exposure optical system 12 as an image writing means for each color moves the exposure position on the photosensitive drum 10 between the scorotron charger 11 and the developing unit 13 and the photosensitive unit with respect to the developing unit 13. It is arranged inside the photoconductor drum 10 in a state provided on the upstream side in the rotation direction of the drum 10.

The exposure optical system 12 performs image processing based on image data of each color sent from a separate computer (not shown) and stored in a memory, and then performs image processing on a uniformly charged photosensitive drum 10. Exposure is performed to form a latent image on the photosensitive drum 10. The emission wavelength of the light-emitting element used in this embodiment is usually 6 for the toners of Y, M, and C, which have high translucency.
The wavelength in the range of 80 to 900 nm is good, but the wavelength may be shorter than this, since the color toner does not have sufficient translucency since image exposure is performed from the back surface.

The developing device 13 as a developing means for each color includes
Inside yellow (Y), magenta (M), cyan (C)
Alternatively, it contains a black (K) two-component (or one-component) developer and is formed of, for example, a cylindrical nonmagnetic stainless steel or aluminum material having a thickness of 0.5 to 1 mm and an outer diameter of 15 to 25 mm, respectively. Developing sleeve 13a.

In the developing area, the developing sleeve 13a is kept in non-contact with the photosensitive drum 10 by a contact roller (not shown) with a predetermined gap, for example, 100 to 1000 μm, between the developing sleeve 13a and the rotating direction of the photosensitive drum 10. At the closest position, the developing sleeve 13a rotates in the forward direction. At the time of development, a DC voltage of the same polarity as the toner (in the present embodiment, a negative polarity) or a DC voltage superimposed on the DC voltage is applied to the developing sleeve 13a. By applying a bias voltage, non-contact reversal development is performed on the exposed portion of the photoconductor drum 10. At this time, the precision of the development interval needs to be about 20 μm or less in order to prevent image unevenness.

As described above, the developing unit 13 transfers the electrostatic latent image formed on the photosensitive drum 10 by the charging by the scorotron charger 11 and the image exposure by the exposure optical system 12 in a non-contact state. Reversal development is performed with toner having the same polarity as the charge polarity of No. 10 (in the present embodiment, the photosensitive drum is negatively charged, and the toner has negative polarity).

As shown in FIG. 10, the photosensitive drum 10 and the holding member 20 are flange members 10A which are support members for rotatably supporting the photosensitive drum 10 at the rear and front ends of the apparatus. , 10B and the flanges 120A, 120B supporting the holding member 20 are integrally formed via means such as press fitting or screws.
In the photosensitive drum 10, the flange member 10A and the flange member 10B, which are support members thereof, respectively have a bearing B1 and a bearing B2 with respect to the shaft 121 and the flange 120B, which are fixed members integrated with the flange 120A of the holding member 20. It is supported rotatably through the.

The shaft 121 has a shaft portion 121A for holding the photosensitive drum 10, and the back side substrate 70 is provided with a support shaft 130 as a holding means for the shaft 121 having an engagement hole 130A. I have. Engagement hole 130
A is fitted with a linear bearing B4, and the support shaft 130 is fixed to the rear device substrate 70 by screws or the like with the receiving member 130a interposed therebetween. The support shaft 130 is located at the center of the gear G2 that meshes with the drive gear G1, and rotatably supports a conductive member 131 that integrates the gear G2 via a bearing B3. On the other hand, the device substrate 70 on the front side of the device
An opening 70 </ b> A that allows the photosensitive drum 10 that integrates the exposure optical system 12 fixed to the holding member 20 to be inserted and removed is opened.

The holding member 20 inserts the shaft portion 121A of the shaft 121 into the linear bearing B4 provided on the support shaft 130 with respect to the device board 70 on the back side, and
A of the engagement pin 121 of the support shaft 130
By engaging the V-shaped groove formed in 30B and restricting the angular position of the exposure optical system 12, the exposure optical system 12 is attached to the device board 70. The front cover 120D is mounted at a predetermined position by fixing the front cover 120D with the screw 52 while pressing the front cover 120D in the axial direction with the buffer material K interposed therebetween.

The coupling 10C, which is an engagement member attached to the side surface of the flange member 10A, which is a support member for supporting the photosensitive drum 10, and the driving member, which is a coupling member attached to the side surface of the transmission member 131 that integrates the gear G2. The flange member 10 is formed by the pin 131A and the set screw 51.
A coupling portion between the gear A and the gear G2 is formed, and when the photosensitive drum 10 having the holding member 20 integrated therewith is mounted, the coupling 10C attached to the side surface of the flange member 10A.
Is fitted into a drive pin 131A attached to the side surface of the conductive member 131 having the gear G2, and after engagement, the conductive member 131 having the gear G2 and the photosensitive drum 10 having the flange member 10A are aligned at the center and the outer peripheral surface. In the state
The drive pin 131A and the coupling 10C are fixed from the side of the photosensitive drum 10 using the set screw 51, and the flange member 10A and the gear G2 are connected and fixed.

When the image carrier driving motor (not shown) is started by the start of image formation, the rotational power of the driving gear G1 is transmitted to the photosensitive drum 10 via the coupling portion by the gear G2, and the photosensitive drum 10 is moved to the position shown in FIG. , And at the same time, application of a potential to the photosensitive drum 10 is started by the charging action of the Y scorotron charger 11.
After a potential is applied to the photosensitive drum 10, image writing is started by the first color signal, that is, an electric signal corresponding to the Y image data in the Y exposure optical system 12, and the rotation of the photosensitive drum 10 causes the image writing to start. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface. This latent image is reversely developed in a non-contact state by the Y developing device 13, and a yellow (Y) toner image is formed on the photosensitive drum 10.

Next, the photoreceptor drum 10 places an M scorotron charger 11 on the yellow (Y) toner image.
A potential is applied by the charging action of the M exposure optical system 12
Of the yellow (Y) toner image by the non-contact reversal development by the M developing device 13 is performed. A magenta (M) toner image is formed on the image.

By the same process, the cyan (C) toner image corresponding to the third color signal is further obtained by the C scorotron charger 11, the exposure optical system 12, and the developing device 13, and the K scorotron charger 11 , Exposure optical system 1
A black (K) toner image corresponding to the fourth color signal is sequentially superimposed and formed by the second and developing units 13, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10. You.

As described above, in the present embodiment, Y, M,
The exposure of the organic photosensitive layer of the photoconductor drum 10 by the C and K exposure optical systems 12 is performed through a transparent substrate from the inside of the photoconductor drum 10. Therefore, the exposure (image writing) of the image corresponding to the second, third and fourth color signals can form an electrostatic latent image without being shielded by the previously formed toner image. Exposure may be performed from the outside of the photoreceptor drum 10, although it is preferable.

On the other hand, the recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a half-moon-shaped feed roller (no code), and is fed by a feed roller (no code). Timing roller 15b
Transported to

The recording paper P is synchronized with the color toner image carried on the photoreceptor drum 10 by driving the timing roller 15b, and is conveyed by the paper charging device 150 as a transfer material charging means. And is fed to the transfer area. The recording paper P, which has been closely transported by the transport belt 14A, is rotated around the photosensitive drum 10 by a transfer unit 14c as a transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied in a transfer area. The color toner images on the surface are collectively transferred to the recording paper P.

The recording paper P on which the color toner image has been transferred is
The transfer material is neutralized by a transfer material static eliminator 14h as a transfer material static eliminator, separated from the transport belt 14A, and transported to the fixing device 270 of the second example.

The fixing device 270 of the second example includes a hot-roller roller 17a as a roll-shaped hot-wire fixing rotary member for fixing a color toner image, and a ceramic heater 172 as a fixed heating element. A heat-fixing film 27A serving as a lower film-shaped rotating member, and a halogen lamp 171g or xenon that emits heat rays such as infrared rays or far-infrared rays including visible light depending on a light source is provided in the center of the heat ray fixing roller 17a. A lamp (not shown) or the like is provided as a heat ray irradiation unit.

Heat ray fixing roller 17a and heat fixing film 2
7A, the recording paper P is nipped by a nip N, and the color toner image on the recording paper P is fixed by applying heat and pressure. Is discharged to the tray at the top of the device.

The toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is transferred to a cleaning blade 19 provided in a cleaning device 19 as an image forming body cleaning means.
Cleaning is performed by a. The photosensitive drum 10 from which the residual toner has been removed is uniformly charged by the scorotron charger 11, and enters the next image forming cycle.

As shown in FIG. 11, the fixing device 270 according to the second example has a heat-ray fixing roller 17a as an upper roll-shaped heat-ray fixing rotating member for fixing a color toner image.
And a heat fixing film 27A as a lower film-shaped rotating member, and a width formed between the heat ray fixing roller 17a as a soft roller having elasticity and the heat fixing film 27A as a hard roller. At a wide nip portion N of 30 mm or less, preferably 10 mm or more, the recording paper P that enters the nip portion N and passes through the nip portion N
To fix the toner image on the recording paper P by applying heat and pressure.

A heat ray fixing roller 17a as a heat ray fixing rotating member for fixing a toner image on a transfer material has a cylindrical light transmitting substrate 171a and an outer surface (outer peripheral surface) of the light transmitting substrate 171a. Translucent elastic layer 171d and heat ray absorbing layer 17
1b and a release layer 171c are provided in that order as a soft roller. Halogen lamp 171 which is a heat ray irradiating means for emitting a heat ray such as infrared ray or far infrared ray including visible light depending on a light source is provided in the center of the interior of the transparent substrate 171a.
g or a xenon lamp (not shown). The heat ray fixing roller 17a as a heat ray fixing rotating member is configured as a highly elastic soft roller as described later.
A heat ray emitted from the halogen lamp 171g or a xenon lamp (not shown) is absorbed by the heat ray absorbing layer 171b to form a roll-shaped heat ray fixing rotating member capable of rapid heating. Preferably, a heat uniformizing roller TR4 is provided on the surface of the heat ray fixing roller 17a. The heat uniformizing roller TR4 using a heat roller or a metal roller member having good thermal conductivity such as an aluminum material or a stainless steel material. Heat ray fixing roller 17a heated by heat ray absorbing layer 171b
The heat generation temperature distribution on the peripheral surface is made uniform. Heat uniformizing roller T
By R4, the temperature unevenness in the vertical and horizontal directions of the heat ray fixing roller 17a due to the passage of the transfer material is made uniform. TS1 is a temperature sensor attached to the upper heat ray fixing roller 17a and serving as a temperature detecting unit using a contact type thermistor for performing temperature control. As the temperature sensor TS1, a non-contact type sensor can be used in addition to a contact type sensor.

The lower heat fixing film 27A is, for example, a thin fixing film 171 having a thickness of 40 to 100 μm.
A ceramic heater 172 as a fixed heating element, and a heater holder 2 for holding the ceramic heater 172
73 as a hard roller. In addition, it is preferable to provide a metal roller member having good thermal conductivity such as an aluminum material or a stainless steel material, or a heat equalizing roller TR4 using a heat pipe inside the heater holder 273. Thus, the heat generation temperature distribution on the peripheral surface of the heat fixing film 27A heated by the ceramic heater 172 is made uniform. TS2 is a ceramic heater 172 of the lower heat fixing film 27A.
A temperature sensor, which is a temperature detecting means using, for example, a contact-type thermistor for performing temperature control, is attached to the back surface of the sensor. As the temperature sensor TS2, a non-contact type sensor can be used in addition to a contact type sensor.

The heat capacity of the fixing film 171 is about 1/20 that of the heat ray fixing roller 17a, so that a quick start with almost zero warm-up is possible. The heater holder 273 holds the rotating fixing film 17.
1, while being pressed against the heat ray fixing roller 17a via a ceramic heater 172 to be held. The fixing film 171 has a heater holder 273.
The heat ray fixing roller 17 loosely fits into the
The rotation is driven by the surface frictional force a. Heat fixing film 2
Since 7A has a small heat capacity, the heat of the heat ray fixing roller 17a is hardly removed.

The ceramic heater 172 is provided with a resistor and overcoat glass by thick film printing on an alumina substrate, and the thermal resistance between the fixing film 171 is lower than that of the fixed heating element.

The structure of the fixing film 171 is composed of a base material 171A, a conductive layer 171B and a surface release layer 171C, as described above with reference to FIG.

The base material 171A is preferably a polyimide resin having excellent strength and dimensional stability at high temperatures, and preferably has a thickness of about 40 to 100 μm. By increasing the thickness to about 40 μm, the strength and rigidity are increased, and the end of the fixing film 171 during rotation can be regulated without buckling. On the other hand, if the thickness is more than 100 μm, the heat conduction becomes poor, and the heat conduction becomes large, so that it becomes difficult to heat up instantaneously and the electric power used increases.

To prevent offset, the surface release layer 171C, for example, a fluororesin (PFA or PTF)
It is preferable to provide the layer of E), but furthermore, a conductive layer 171B is provided to eliminate the influence of the triboelectric charge generated by the sliding between the inner surface of the base material 171A of the fixing film 171 and the surface of the ceramic heater 172, and is grounded. ing.

Further, a conductive filler is inserted in the surface release layer 171C to reduce the resistance so as to release the charged charges peeled off from the rear end of the recording paper P in a low humidity environment, thereby preventing the offset. However, if the resistance value is too low, the transfer charge leaks and an offset occurs, so that 2 × 10 ^{10 to} 5 × 10 ¹¹ Ω /
A resistance of cm ² is preferred.

The temperature control of the upper heat ray fixing roller 17a and the lower heat fixing film 27A is performed by detecting the temperature of the heat ray fixing roller 17a as the upper heat ray fixing rotating member, as described above with reference to FIG. The temperature of the heat ray fixing roller 17a (T1
(° C.)) and the temperature (T2 (° C.)) of the heat fixing film 27A by the temperature sensor TS2 as a temperature detecting means for detecting the temperature of the ceramic heater 172 of the heat fixing film 27A as the lower film-shaped rotating member. And a halogen lamp 171g or a xenon lamp from a reference table corresponding to the temperature (detection temperature) T1 and the temperature (detection temperature) T2 stored in advance in a ROM of a storage unit (ROM, RAM) as a reference table. The temperature of the upper heat ray fixing roller 17a and the lower heat fixing film 27A are controlled by referring to the (not shown) and the on-off time of the ceramic heater 172 through the fixing control unit. In particular, the heating control is performed from both sides in order to shorten the warm-up time. However, the temperature control of the fixing after the warming-up is performed quickly by controlling the heating from both sides. In particular, in the case of fixing a color toner image, since both the temperature of the upper heat ray fixing roller 17a and the temperature of the lower heat fixing film 27A affect glossiness and color, both temperature controls are necessary.

A nip portion N having a convex upper side is provided between the upper highly elastic soft roller and the lower hard roller, following the circular upper surface shape of the heater holder 273 of the lower heat fixing film 27A. Is formed, and the toner image is fixed.

The heat generation in the heat ray absorbing layer 171b by the heat rays of the halogen lamp 171g or the xenon lamp (not shown) and the heat generation of the ceramic heater 172 as the fixed heating element save energy and quick start (rapid heating) with a short warm-up time. A possible fixing device becomes possible.

As described above with reference to FIG. 5, the configuration of the heat ray fixing roller 17a is, as shown in the cross section in FIG.
m, preferably 2-5 mm thick, halogen lamp 171
g or a ceramic material such as sapphire (Al ₂ O ₃ ) or CaF ₂ which transmits heat rays such as infrared rays or far infrared rays from a xenon lamp (not shown) (heat conductivity is (5-20) × 10 ^{− 3} J / cm · s · K, specific heat (0.5-2.0) × J / g · K, specific gravity 1.5–3.
0) is mainly used, and a translucent resin using polyimide, polyamide or the like (having a thermal conductivity of (2-4) × 10 ⁻³ )
J / cm · s · K, specific heat of (1-2) × J / g · K, specific gravity of 0.8-1.2) and the like can also be used. For example, as the translucent substrate 171a of the heat ray fixing roller 17a, the inner diameter is 32 mm, the outer diameter is 40 mm, and the layer thickness (thickness) is 4 m.
m Pyrex glass (specific heat 0.78 J / g · K,
When the specific gravity is 2.32), the heat capacity Q1 per A-3 size width (297 mm) of the translucent substrate 171a is about 60 cal / deg. In addition, the translucent substrate 171
Since the wavelength of the heat ray passing through a is 0.1 to 20 μm, preferably 0.3 to 3 μm, a modifier for hardness and thermal conductivity is added as a filler, but the particle size is １ ／ of the wavelength of the heat ray. Heat ray transmittance of 1 μm or less, preferably 1 μm or less, preferably 0.1 μm or less, preferably 1/5 or less, including primary and secondary particles. The transparent substrate 171a may be formed by dispersing fine particles of metal oxide such as ITO, titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder. The average particle size including primary and secondary particles in the layer is 1μ.
m or less, preferably 0.1 μm or less is preferable for preventing light scattering and reaching the heat ray absorbing layer 171b. As described above, the translucent substrate 171a does not have good thermal conductivity.

The light-transmitting elastic layer 171d has a thickness of 0.5 to 2 mm.
It is formed of a rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light or infrared rays depending on the light source) using, for example, silicon rubber or fluorine rubber having a thickness of 0 mm, preferably 1 to 5 mm. . Translucent elastic layer 171d
In order to respond to high speed, a method of improving thermal conductivity by mixing a metal oxide powder such as silica, alumina or magnesium oxide as a filler into a base layer (silicone rubber or fluorine rubber) has been adopted. Conductivity (1-3)
× 10 ⁻³ J / cm · s · K, specific heat of (1-2) × J / g
-Use a rubber layer having a K and a specific gravity of 0.9 to 1.0. For example, as the translucent elastic layer 171d of the heat ray fixing roller 17a,
A-3 size width of the light-transmitting elastic layer 171d when silicon rubber having an outer diameter of 50 mm and a layer thickness (thickness) of 5 mm (specific heat is 1.1 J / g · K, specific gravity is 0.91) is used ( 297
The heat capacity Q2 per mm) is about 50 cal / deg. The rubber layer is made of a light-transmitting substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J / cm · s ·
Since it is an order of magnitude lower than K), it functions as a layer having heat insulating properties.
When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a hardness of 40 Hs usually has a hardness of 60 Hs (JIS,
A rubber hardness). Preferred rubber hardness is 5 to 60 Hs. Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is coated with a fluorine-based rubber having a thickness of 20 to 300 μm as an oil-resistant layer to prevent oil swelling. As the silicon rubber of the top layer of the translucent elastic layer 171d, HTV (High Temp) is used.
RTV (RoomTemperature V) which has better releasability than ETERNUS
olcanizing) and LTV (Low Tempe)
(ratio volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, the wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm, and preferably 0.3 to 3 μm. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less including primary and secondary particles,
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
71d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 1 as a heat ray fixing rotating member is provided.
7a is configured as a highly elastic soft roller.

As the heat ray absorbing layer 171b, the remaining heat rays emitted from a halogen lamp 171g or a xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d are used as the heat transmitting layer 171b. 90 to 100%, preferably 95 to 100% of the heat rays, which are about 100% of the heat rays transmitted through the 171a and the translucent elastic layer 171d, are absorbed by the heat ray absorbing layer 171b to form a heat ray fixing rotating member capable of instantaneous heating. As described above, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F
e ₂ O ₃ ) or the like, and a heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm is sprayed on the outer side (outer peripheral surface) of the light transmitting elastic layer 171 d. It is formed by coating or the like. Heat ray absorbing layer 171
b has a thermal conductivity of the rubber layer of the translucent elastic layer 171d (having a thermal conductivity of (1-3) × 10 ⁻³ J / cm · s · K and a specific heat of (1-2) × J / g · K, specific gravity is 0.9 to 1.0), and a slightly higher (3 to 10) × 10 ⁻³ J / cm · s · K (specific heat is increased by adding an absorbent such as carbon black). 2.0) × J / g · K, and the specific gravity can be set to (〜0.9). As the heat ray absorbing layer 171b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%,
For example, if it is about 20 to 80%, the heat rays leak, and when the heat ray fixing roller 17a as a heat ray fixing rotating member is used for monochrome image formation due to the leaked heat rays, a specific position of the heat ray fixing roller 17a is determined by filming or the like. When the black toner adheres to the surface of the device, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of the heat rays is further superimposed on the portion to damage the heat ray absorbing layer 171b. In addition, when used for forming a color image, the absorption efficiency of the color toner is generally low, and there is a difference in the absorption efficiency between the color toners, resulting in poor fixing or uneven fixing. Therefore, light is emitted from the halogen lamp 171g or a xenon lamp (not shown), and the light-transmitting base 171a and the light-transmitting elastic layer 171 are emitted.
The remaining heat rays absorbed by the light-transmitting substrate 171a and the light-transmitting elastic layer 171d are the remaining heat rays absorbed by the heat ray absorbing layer 1.
The heat ray absorption rate of the heat ray absorbing layer 171b is set to 90 to 100%, which is substantially 100%, and preferably 95 to 100% so that the heat ray is completely absorbed by 71b. Accordingly, the color toner, which is difficult to be fixed by heat rays due to the different spectral characteristics, is favorably melted. Particularly, in the color image formation in FIG. 9, it is difficult to fix by the heat rays due to the different spectral characteristics. The superimposed color toner image on the transfer material having a thick toner layer is fused well. Further, when the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate due to the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b is damaged by local heating by the thin film and the cause of the insufficient strength. And the thickness of the heat ray absorbing layer 171b is 5
If the thickness exceeds 00 μm, the heat conduction becomes poor,
The heat capacity becomes large and rapid heating becomes difficult. The heat ray absorption rate of the heat ray absorption layer 171b is about 90%, which is about 100%.
100%, preferably 95 to 100%, and the thickness of the heat ray absorbing layer 171b is 10 to 500 μm, preferably 2 to 500 μm.
By setting the thickness to 0 to 100 μm, the heat ray absorbing layer 171 b
Local heat generation is prevented, and uniform heat generation is performed.
Since the wavelength of the heat ray projected on the heat ray absorbing layer 171b is 0.1 to 20 μm, preferably 0.3 to 3 μm, a hardness or thermal conductivity modifier is added as a filler. An average particle diameter of 1 μm or less, including primary and secondary particles of 線, preferably １ ／ or less, of the wavelength of the heat ray;
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
The heat ray absorbing layer 171b may be formed by dispersing 5 to 50% by weight of fine particles of a metal oxide such as magnesium oxide and calcium carbonate in a resin binder. In this way, the heat capacity of the heat ray absorbing layer 171b is reduced so that the temperature rises immediately. Therefore, the temperature of the heat ray fixing roller 17a as a heat ray fixing rotating member is lowered, and the fixing unevenness occurs. To prevent. As the heat ray absorbing layer 171b, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, and red iron (Fe ₂ O ₃ ) may be used in addition to silicon rubber or fluoro rubber having elasticity. Or a mixture of such powders may be used.
For example, as a heat ray absorbing layer 171b (or a dual-purpose layer 171Z described later) of the heat ray fixing roller 17a, a 50 μm outer diameter (transparent elastic layer) 171d surface (peripheral surface) is coated with a 50 μm-thick fluororesin (specific heat). Is 2.0 J / g · K,
A-3 size width (297 mm) of the heat ray absorbing layer 171b (or the dual-purpose layer 171Z) when the specific gravity is 0.9)
The heat capacity Q3 per hit is about 1.0 cal / deg. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

Further, a PFA (fluororesin) tube having a thickness of 30 to 100 μm is coated on the outer side (outer peripheral surface) of the heat ray absorbing layer 171b separately from the heat ray absorbing layer 171b to improve the releasability from the toner. Or fluororesin (PF
A or PTFE) Release layer 171c coated with a paint of 20 to 30 μm (having a thermal conductivity of (1 to 10) × 10 ⁻³ J / cm.
S · K, specific heat (（2.0) × J / g · K, specific gravity (〜0.9)) (separated type).

Further, as shown in the cross section in FIG. 5B, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron (Fe ₂ O ₃ ), etc. Heat-absorbing member mixed with powder of PTFE, and a fluororesin (PFA or PT) that also serves as a binder and a release agent
FE) paint is mixed and mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG.
A heat-fixing rotary member in the form of a roll having elasticity may be formed outside (outer peripheral surface) of the translucent elastic layer 171d formed outside (outer peripheral surface). The thermal conductivity of the dual-purpose layer 171Z is substantially the same as the thermal conductivity of the heat ray absorbing layer 171b.
(3-10) × 10 ⁻³ J / cm · s · K (specific heat
2.0) × J / g · K, and specific gravity is (０．９0.9).
As described above, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the translucent base 171a and the translucent elastic layer 171d are:
In order to completely absorb the heat rays transmitted through the light-transmitting base 171a and the light-transmitting elastic layer 171d, the heat ray absorptivity of the dual-purpose layer 171Z is set to 90 to 100%, which is about 100%, and preferably 95 to 100%. When the heat ray absorptivity in the dual-purpose layer 171Z is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the heat ray fixing rotating member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the heat ray fixing rotating member at a specific position due to, for example, mining, heat is generated from the adhering portion by the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the dual-purpose layer 171Z. When used for color image formation, the color toner absorption efficiency is generally low,
In addition, since there is a difference in the absorption efficiency between the color toners, a fixing failure occurs or fixing unevenness occurs. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The combined layer 171Z has a heat ray absorptivity of about 90% to 100%, preferably about 100%, preferably 9 so that the heat rays transmitted through the heat ray fixing rotary member are completely absorbed in the heat ray fixing rotating member.
5 to 100%. Further, local heat generation in the dual-purpose layer 171Z is also prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the dual-purpose layer 171Z is 0.1 to 20 μm.
m, preferably 0.3 to 3 μm, so that a filler for adjusting hardness or thermal conductivity is added as a filler. 2
The average particle size including the secondary particles is 1 μm or less, preferably 0.1 μm or less.
Fine particles of metal oxide such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, calcium carbonate, etc. having a heat ray transmission of 1 μm or less (infrared ray or visible ray including visible light depending on the light source) are used as resin binder. May be formed to form the dual-purpose layer 171Z.

As described above with reference to FIG. 6, if the concentration distribution of the above-mentioned heat ray absorbing member is uniformly provided on the heat ray absorbing layer 171b of the heat ray fixing roller 17a as a rotating member for heat ray fixing in the form of a roll, the heat ray at the boundary is formed. Heat is concentrated in the absorption layer 171b, and the heat easily flows to the side of the light-transmitting elastic layer 171d. Therefore, the heat-ray absorption layer 171b may be formed by using a lower heat-conductive member than the light-transmitting substrate 171a or by providing a concentration distribution. It is preferable to generate heat inside from the viewpoint of dispersing the heat generation distribution. As shown in the graph (a), the concentration distribution of the heat ray absorbing layer 171b is set such that the interface on the side of the light-transmitting elastic layer 171d adjacent thereto has a low concentration, is gradually inclined toward the outer peripheral surface side, and is gradually increased. (Thickness t of heat ray absorbing layer 171b)
1/3 from the light-transmitting elastic layer 171d side.
(Position of about degree) so as to obtain a concentration that absorbs 100% so as to be saturated. Thereby, the heat ray absorbing layer 171b
As shown in the graph (b), the heat generation distribution due to the absorption of the heat ray at the point has a maximum value near the center of the heat ray absorption layer 171b and a minimum value near the interface and the outer peripheral surface of the heat ray absorption layer 171b. It is formed in a shape. Alternatively, the heat ray absorbing layer 171b
It is preferable to provide a light-transmissive heat-resistant resin (polyimide, fluororesin or silicon resin) with a thickness of 10 to 500 μm, preferably 20 to 100 μm on the interface or the outer peripheral surface of the substrate. Further, it is preferable to suppress heat loss as a member having a lower thermal conductivity than the translucent substrate 171a. This reduces heat generation due to absorption of heat rays at the interface, prevents heat from flowing out, and prevents damage to the adhesive layer and heat ray absorbing layer 171b at the interface. In addition, before the outer peripheral surface side (the heat ray absorbing layer 171).
2/3 from the light-transmitting base 171a side with respect to the thickness t1 of b.
(About ４ of the position) to saturate the concentration distribution from the outer peripheral surface to the outer peripheral surface. Note that a saturated layer may be formed as shown by a dotted line. In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle.

As described above with reference to FIG. 7, the outer diameter φ of the cylindrical light-transmitting substrate 171a of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is set to 15 to 15.
A thickness t of 60 mm is used. A thicker thickness t is better in terms of strength, and a thinner thickness is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the thickness t is outside the cylindrical light-transmitting base 171a. The relationship between the diameter φ and the thickness t is 0.02 ≦ t / φ ≦ 0.20, and preferably 0.04 ≦ t / φ ≦ 0.10. When the outer diameter φ of the transparent substrate 171a is 40 mm, the thickness t of the transparent substrate 171a is 0.8 mm ≦ t ≦ 8 m.
m, preferably 1.6 mm ≦ t ≦ 4.0 mm. When t / φ is less than 0.02 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.20, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, depending on the material, a light-transmitting substrate may absorb about 1 to 20% of heat rays, and it is preferable that the substrate be thin as long as the strength can be maintained.

As described above, by using the fixing device 270 of the second example described with reference to FIG. 11, the lower thermal fixing is provided between the upper elastic soft roller and the lower hard roller. A nip portion N having a convex upper side is formed following the circular upper surface shape of the heater holder 273 of the film 27A, and the toner image is fixed.
Both the heat generated by the heat ray absorbing layer 171b due to the heat rays of the 71g and the xenon lamp (not shown) and the heat generated by the ceramic heater 172 as the fixed heating element, and particularly the heat generated by the lower ceramic heater 172 causes the upper heat ray. Image formation that can quickly heat the heat ray absorbing layer 171b of the fixing roller 17a, enables high-speed fixing while saving energy and shortens the warm-up time, and obtains good fixing properties with a uniform and stable temperature. The device becomes possible. In particular, by fixing the toner image with the upper elastic roller (heat ray fixing roller 17a) having high elasticity, high-quality (good fixing performance) fixing is performed.

Embodiment 3 A third embodiment of the fixing apparatus according to the present invention and an embodiment of an image forming apparatus in which the fixing apparatus is applied to the first example of the image forming apparatus described in the first embodiment. The image forming process and each mechanism will be described with reference to FIG. 12 or FIG. 13 and FIGS. 2, 4 to 8 described in the first embodiment. FIG. 12 is a sectional configuration diagram of an image forming apparatus showing an embodiment of a third example of the image forming apparatus according to the present invention, and FIG. 13 is a sectional configuration of a third example of the fixing device according to the present invention. FIG. In the following description of the embodiment of the image forming apparatus of the third example, in the transfer material supported and transported by the intermediate transfer body, the surface on the side facing the image carrier is the surface,
The other surface, that is, the surface facing the intermediate transfer member is called a back surface, an image transferred to the front surface of the transfer material is called a front image, and an image transferred to the back surface of the transfer material is called a back image.

In FIG. 12, reference numeral 10 denotes a photosensitive drum serving as an image carrier, 11 denotes a scorotron charger serving as charging means for each color, 12 denotes an exposure optical system serving as image writing means for each color, and 13 denotes an exposure optical system for each color. A developing device 14a, an intermediate transfer belt as an intermediate transfer member, and 14b for transferring the toner image on the image carrier to the surface of the intermediate transfer member and the transfer material 1
A primary transfer device as a secondary transfer device; 14g, a secondary transfer device as a secondary transfer device for transferring the toner image on the intermediate transfer member to the back surface of the transfer material; 150, a paper charger as a transfer material charging device;
14h is a transfer material static eliminator as a transfer material static elimination means, 160 is a separation claw 210 as a claw member and a spur 162 as a spur member.
Is a fixing device of the third example.

The photosensitive drum 10, which is an image carrier, has a transparent conductive layer, a, on the outer periphery of a cylindrical substrate formed of a transparent member such as optical glass or transparent acrylic resin.
A photosensitive layer such as an Si layer or an organic photosensitive layer (OPC). The conductive layer is grounded, and an image carrier driving motor (not shown) is driven clockwise as indicated by an arrow in FIG. It is rotated at a linear speed of 400 mm / sec.

The toner image forming means for forming a toner image on the image carrier is a scorotron charger 11, which is a charging means.
A laser exposure optical system 120 as an image writing unit and a developing unit 13 as a developing unit are arranged in this order with respect to the rotation direction of the photosensitive drum 10 indicated by an arrow in FIG.

Scorotron charger 11 as charging means
Is a control grid maintained at a predetermined potential (unsigned)
And a discharge electrode 11a formed of, for example, a sawtooth electrode,
It is attached to face the photosensitive layer of the photosensitive drum 10 and is charged by corona discharge having the same polarity as the toner (in the present embodiment, the polarity of the toner used is set to minus polarity.
In the present embodiment, the scorotron charger 11 serving as a charging unit performs negative charging (to charge the photosensitive drum 10 uniformly). As the discharge electrode 11a, a wire electrode or a needle electrode may be used.

Laser exposure optical system 12 as image writing means
Reference numeral 0 denotes a semiconductor laser as a light emitting element (not shown), a rotary polygon mirror 120b for rotating and scanning a laser beam emitted from the semiconductor laser, an fθ lens 120c, and a reflection mirror 12
The laser beam emitted from the semiconductor laser is rotationally scanned by a rotating polygon mirror 120b, and is read by a separate image reading device onto the rotating photosensitive drum 10 via an fθ lens 120c and a reflecting mirror 120d. Then, an image is written on the photosensitive layer of the photosensitive drum 10 according to the image data stored in the memory, and an electrostatic latent image is formed on the photosensitive drum 10. It is necessary to change the image data so that the image data corresponding to the front image and the image data corresponding to the back image are mirror images of each other.

The developing device 13 as a developing means keeps a predetermined gap with respect to the peripheral surface of the photosensitive drum 10 and rotates in a forward direction with respect to the rotating direction of the photosensitive drum 10 at a developing position. A developing sleeve 13a formed of a cylindrical nonmagnetic stainless steel or aluminum material having an outer diameter of 15 to 25 mm, and a one-component or two-component developer of black (K) is accommodated inside the developing device 13 are doing. The developing sleeve 13a of the developing device 13 is provided with a predetermined gap, for example, 100 to
The developer on the developing sleeve 13a having a layer thickness of 80 to 300 μm is kept out of contact with the photosensitive drum 10 with a gap of 500 μm, and a developing bias in which a DC voltage and an AC voltage are superimposed is applied to the developing sleeve 13a. As a result, non-contact reversal development is performed, and a toner image is formed on the photosensitive drum 10.

Intermediate transfer belt 14a as an intermediate transfer member
Preferably has a volume resistivity of 10 ⁹ Ω · cm or more,
It is an endless belt of less than ¹² Ωcm, for example, a modified polyimide, a thermosetting polyimide, an ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, a thickness of 0.1 to 0.1 in which a conductive material is dispersed in an engineering plastic such as nylon alloy. It is a seamless belt having a two-layer structure in which a 1.0 mm semiconductive film substrate is coated with a fluorine coating having a thickness of 5 to 50 μm, preferably as a toner filming preventing layer. In addition, as the base of the intermediate transfer belt 14a, a semiconductive rubber belt having a thickness of 0.5 to 2.0 mm in which a conductive material is dispersed in silicon rubber or urethane rubber or the like can be used. The intermediate transfer belt 14a includes a driving roller 1 that is a roller member.
4d, the secondary transfer facing roller 14j, the driven roller 14e, and the tension roller 14i, and are rotated counterclockwise as indicated by the arrow in FIG. The driven roller 14e, the secondary transfer opposing roller 14j, and the driving roller 14d are rotated at a fixed position, and the tension roller 14i is movably supported and rotated by an elastic force such as a spring (not shown). The drive roller 14d is rotated by a drive from an intermediate transfer member drive motor (not shown), and drives and rotates the intermediate transfer belt 14a. The rotation of the intermediate transfer belt 14a causes the secondary transfer opposing roller 14j, the driven roller 14e, and the tension roller 14i to be driven and rotated. The slack of the rotating intermediate transfer belt 14a is tensioned by the tension roller 14i. The intermediate transfer belt 14a is driven
The recording paper P, which is a transfer material, is supplied to a position where the recording paper P is stretched around e, and is supported and conveyed by the intermediate transfer belt 14a. The recording paper P is separated from the intermediate transfer belt 14a at a curvature portion KT at the end of the intermediate transfer belt 14a stretched around the drive roller 14d on the fixing device 370 side.

A primary transfer unit 14b as a primary transfer unit for transferring the toner image on the image carrier to the surface of the intermediate transfer member or the transfer material is opposed to the photosensitive drum 10 with the intermediate transfer belt 14a interposed therebetween. The corona discharger is provided, and forms a transfer area (no reference numeral) between the intermediate transfer belt 14a and the photosensitive drum 10. A DC voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied to the primary transfer device 14b, and the toner image on the photosensitive drum 10 is transferred onto the intermediate transfer belt 14a or the recording paper P as a transfer material. Transfer to the surface. As the primary transfer device 14b, a transfer roller or a transfer blade can be used in addition to the corona discharge device.

A secondary transfer device 14g, which is a secondary transfer means for retransferring the toner image on the intermediate transfer member to the back surface of the transfer material, is constituted by a corona discharger, and is provided between the primary transfer device 14b and the driving roller 14d. And is provided to face the secondary transfer facing roller 14j that is grounded with the intermediate transfer belt 14a interposed therebetween.
Polarity opposite to toner (positive polarity in this embodiment)
Is applied to transfer the toner image on the intermediate transfer belt 14a to the back surface of the recording paper P.

The paper charger 150, which is a transfer material charging means, is preferably constituted by a corona discharger, provided opposite to the driven roller 14e, which is grounded across the intermediate transfer belt 14a, and has the same polarity as the toner (this embodiment). (In the embodiment, a negative polarity) is applied, and the recording paper P is charged and attracted to the intermediate transfer belt 14a. As the paper charger 150, in addition to the corona discharger, a paper charging brush or a paper charging roller capable of abutting and releasing the saw-toothed electrode and the intermediate transfer belt 14a may be used.

The transfer material charge eliminator 14h serving as the transfer material charge removal means.
Is a driving roller, which is preferably constituted by a corona discharger, and is grounded with the intermediate transfer belt 14a interposed therebetween near the position where the recording paper P is separated from the intermediate transfer belt 14a at the end of the intermediate transfer belt 14a on the fixing device 370 side. An AC voltage superimposed with a DC voltage for preventing separation discharge at the time of separating a surface toner image having a high charge amount (Q / M) charged by the secondary transfer device 14g and provided by the secondary transfer device 14g; The recording paper P conveyed by the intermediate transfer belt 14a is discharged and separated from the intermediate transfer belt 14a.

The transport section 160 has a separation claw 210 as a transfer material separation assisting means and a spur 162 as a spur member.
The intermediate transfer belt 14a is provided between the curvature section KT at the end of the fixing device 370 side and the fixing device 370 of the third example. The transport unit 160 is heated by the heat from the fixing device 370.
If the intermediate transfer belt 14a is deformed or the intermediate transfer belt 1
This prevents the toner image carried on the transfer belt 4a from becoming slightly fused and difficult to transfer, and prevents the toner from being fixed on the intermediate transfer belt 14a.

The separation claw 210, which is a transfer material separation assisting means, is close to the curvature portion KT of the intermediate transfer belt 14a and has a predetermined distance from the intermediate transfer belt 14a, preferably 0.1 to 2.0.
When the recording paper P is separated from the intermediate transfer belt 14a, the recording paper P is bent toward the intermediate transfer belt 14a to be conveyed when the recording paper P is separated from the intermediate transfer belt 14a. To assist the curvature separation of the recording paper P.

The spur 162, which is a spur member, has a plurality of projections 162a on its peripheral surface, and is provided rotatably about a rotation support shaft 165. The spur 162 guides the back side of the recording sheet P to convey the recording sheet P, prevents the back side toner image of the recording sheet P having the toner image on both sides from being disturbed, and also fixes the recording sheet P to the fixing device 370. The recording paper P is stably conveyed to the fixing device 370 while keeping the entering direction constant.

The separation claw 210 and the spur 162 are disposed on the side opposite to the photosensitive drum 10 with respect to the transfer material conveying surface on the intermediate transfer belt 14a or its extension surface.
It is also possible to provide spurs 162 as spur members on both sides of the transfer material conveying surface or an extension surface thereof.

A fixing device 370 of the third example includes a heat fixing film as a film-shaped rotating member for fixing a toner image of an upper surface image on the upper side (front side) by enclosing a magnetic material 372 as an induction heating element. 37A and a lower heat roller fixing roller 17a serving as a lower roll-shaped heat ray fixing rotating member for fixing the toner image of the lower (back side) image, and a fixing drive motor (not shown) As a result, the heat ray fixing roller 17a is driven to rotate, and the heat fixing film 17A is driven to rotate. A halogen lamp 171g or a xenon lamp (not shown) that emits a heat ray such as an infrared ray or a far-infrared ray including visible light depending on a light source is disposed as a heat ray irradiating means in the center of the heat ray fixing roller 17a.
The recording paper P is sandwiched by a nip N formed between the heat fixing film 37A and the heat ray fixing roller 17a, and the toner image on the recording paper P is fixed by applying heat and pressure.

Next, the image forming process will be described.

When the image recording member drive motor (not shown) is started by the start of image recording, the photosensitive drum 10 is rotated clockwise as shown by the arrow in FIG. The application of the potential is started.

After the photosensitive drum 10 is applied with a potential, the laser exposure optical system 120 starts image writing by an electric signal corresponding to the image data, and the surface of the photosensitive drum 10 corresponds to the original image. An electrostatic latent image is formed.

The electrostatic latent image is reversely developed by the developing device 13 in a non-contact state, and a toner image is formed on the photosensitive drum 10 (toner image forming means).

The toner image to be the back side image formed on the photosensitive drum 10 as the image carrier by the above-described image forming process is transferred to the intermediate transfer body by the primary transfer unit 14b in the transfer area (no symbol). A certain intermediate transfer belt 14
(a) of FIG. 2 (FIG. 2 (A)).

The toner remaining on the peripheral surface of the photoconductive drum 10 after the transfer is subjected to static elimination by the photoconductive drum AC static eliminator 16 and then enters a cleaning device 19 as image carrier cleaning means. Is cleaned by a cleaning blade 19a made of a rubber material, and is collected by a screw 19b in a toner discharge container (not shown).

After the toner image serving as the back side image is formed on the intermediate transfer belt 14a as described above, the toner image serving as the front side image is continuously formed on the photosensitive drum 10 in the same manner as the above-described image forming process. Is formed (see FIG. 2).
(B)). At this time, the image data is changed so that the front surface image formed on the photosensitive drum 10 is a mirror image of the rear surface image formed on the photosensitive drum 10.

With the formation of a surface image on the photosensitive drum 10, recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a feed roller 15a, and is used as a transfer material feed means. Timing roller 1
The toner image of the front surface image formed on the photosensitive drum 10 and the toner image of the back surface image carried on the intermediate transfer belt 14a are transferred in synchronization by the driving of the timing roller 15b. Area (unsigned). At this time, the fed recording paper P is transferred to a paper charger 15 serving as a transfer material charging unit provided on the front side of the recording paper P.
0, the intermediate transfer belt 1 is charged to the same polarity as the toner.
4a, and is conveyed to the transfer area (no symbol). By charging the paper with the same polarity as the toner, the toner image is prevented from being attracted to the toner image on the intermediate transfer belt 14a and the toner image on the photosensitive drum 10, thereby preventing the toner image from being disturbed.

In the transfer area (no sign), the surface image on the photosensitive drum 10 is transferred onto the surface of the recording paper P by the primary transfer device 14b to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied. Transcribed. At this time, the back surface image on the intermediate transfer belt 14a is not transferred to the recording paper P but exists on the intermediate transfer belt 14a.

The recording paper P on which the toner image has been transferred is
Polarity opposite to toner (positive polarity in this embodiment)
Is transferred to the secondary transfer device 14g to which the voltage of
The backside image on the peripheral surface of the intermediate transfer belt 14a is retransferred to the backside of the recording paper P by the next transfer unit 14g (FIG. 2).
(C)).

The recording paper P on which toner images are formed on both sides is
The curvature of the curvature portion KT of the intermediate transfer belt 14a, the charge removal operation by the transfer material charge remover 14h as the transfer material charge removal means provided at the end of the intermediate transfer belt 14a, and the conveyance with a predetermined interval from the intermediate transfer belt 14a The separation claw 210 provided in the section 160 separates the intermediate transfer belt 14a from the intermediate transfer belt 14a, is conveyed to a fixing device 370 through a spur 162 provided in the conveyance section 160, and is disposed between the heat fixing film 17A and the heat ray fixing roller 17a. The toner image on the recording paper P is fixed by being conveyed between the nip portions N and subjected to heat and pressure in the nip portion N. The recording paper P on which double-sided image recording has been performed is sent upside down, and is discharged by a discharge roller 18 to a tray outside the apparatus.

The toner remaining on the peripheral surface of the intermediate transfer belt 14a after the transfer is provided to face the driven roller 14e with the intermediate transfer belt 14a interposed therebetween, and is applied to the intermediate transfer belt 14a with the support shaft 142 as a rotation fulcrum. The intermediate transfer member is cleaned by an intermediate transfer member cleaning device 140 which is an intermediate transfer member cleaning unit having an intermediate transfer member cleaning blade 141 capable of contacting and releasing contact.

The toner remaining on the peripheral surface of the photoreceptor drum 10 after the transfer is subjected to static elimination by the photoreceptor drum AC static eliminator 16 and then cleaned by the cleaning device 19 to be used in the next image forming cycle. Yes.

As shown in FIG. 13, the fixing device 370 of the third example has a heat fixing film 3 as a film-like rotating member for fixing a toner image of an upper surface (front surface).
7A and a heat-fixing roller 17a as a lower roll-shaped heat-ray fixing rotating member for fixing a toner image of a lower (back-side) rear surface image, and a heat-fixing film 37A as a hard roller. And a wide nip portion N having a width of 30 mm or less, preferably 10 mm or more, formed between the heat ray fixing roller 17a as an elastic soft roller, enters the nip portion N and passes through the nip portion N. The recording paper P is nipped, and the toner image on the recording paper P is fixed by applying heat and pressure.

The heat fixing film 37A for fixing the toner image of the surface image includes, for example, a thin fixing film 171 having a thickness of 40 to 100 μm and a magnetic material 372 as an induction heating element.
And a coil 373 for induction heating the magnetic body 372 as a hard roller. TS2 is a temperature sensor, which is a temperature detecting unit using, for example, a contact-type thermistor for performing temperature control, which is attached to the back surface (the side opposite to the nip portion N) of the magnetic body 372 of the upper heat fixing film 37A. As the temperature sensor TS2, a non-contact type sensor can be used in addition to a contact type sensor.

The heat capacity of the fixing film 171 is about 1/20 that of the heat ray fixing roller 17a, so that a quick start with almost zero warm-up is possible. The magnetic body 372 serves as a running guide for the rotating fixing film 171 and is pressed against the heat ray fixing roller 17a. The fixing film 171 is made of a magnetic material 372.
The heat ray fixing roller 17 loosely fits into the
The rotation is driven by the surface frictional force a. Heat fixing film 3
Since 7A has a small heat capacity, the heat of the heat ray fixing roller 17a is hardly removed.

As the magnetic material 372, a metal base such as alumina or iron oxide provided with a resistor and an overcoat glass by thick film printing is used.
Lowering the thermal resistance between them.

The structure of the fixing film 171 includes a base material 171A, a conductive layer 171B, and a surface release layer 171C, as described above with reference to FIG.

As the base material 171A, a polyimide resin excellent in strength and dimensional stability at high temperatures is preferable, and the thickness is preferably as thick as about 40 to 100 μm. By increasing the thickness to about 40 μm, the strength and rigidity are increased, and the end of the fixing film 171 during rotation can be regulated without buckling. On the other hand, if the thickness is more than 100 μm, the heat conduction becomes poor, and the heat conduction becomes large, so that it becomes difficult to heat up instantaneously and the electric power used increases. In order to prevent offset, it is preferable to provide a surface release layer 171C, for example, a layer of a fluororesin (PFA or PTFE), and further, a gap between the inner surface of the base material 171A of the fixing film 171 and the surface of the magnetic body 372. The conductive layer 171B is provided and grounded in order to eliminate the influence of the triboelectric charge generated by the sliding of. Also, a conductive filler is inserted in the surface release layer 171C to reduce the resistance so as to release the charged charges peeled off from the rear end of the recording paper P in a low humidity environment, thereby preventing the offset. However, if the resistance value is too low, the transfer charge leaks to cause an offset, so that 2 × 10 ^{10 to} 5 × 10 ¹¹ Ω / cm ²
Is preferable.

The heat ray fixing roller 17a as a heat ray fixing rotating member for fixing the toner image on the back surface has a cylindrical light transmitting base 171a and a light transmitting outside (outer peripheral surface) of the light transmitting base 171a. Elastic layer 171d and heat ray absorbing layer 171
b and a release layer 171c are provided as a soft roller in that order. A halogen lamp 171g, which is a heat ray irradiating means for emitting heat rays such as infrared rays or far infrared rays including visible light depending on a light source, is provided in the center of the inside of the light transmitting substrate 171a.
And a xenon lamp (not shown). The heat ray fixing roller 17a as a heat ray fixing rotating member is configured as a highly elastic soft roller as described later. A heat ray emitted from the halogen lamp 171g or a xenon lamp (not shown) is absorbed by the heat ray absorbing layer 171b to form a roll-shaped heat ray fixing rotating member capable of rapid heating. It is preferable that a heat equalizing roller TR4 be provided on the surface of the heat ray fixing roller 17a. The heat generation temperature distribution on the peripheral surface of the heat ray fixing roller 17a heated by the heat ray absorption layer 171b is made uniform. Heat uniformizing roller TR
4, uniformity of the temperature unevenness in the vertical and horizontal directions of the heat ray fixing roller 17a caused by the passage of the transfer material is made uniform. TS1 is a temperature sensor attached to the lower heat ray fixing roller 17a, which is a temperature sensor using a contact type thermistor for performing temperature control. As the temperature sensor TS1, a non-contact type sensor can be used in addition to a contact type sensor.

The temperature control of the upper heat fixing film 37A and the lower heat ray fixing roller 17a is performed by controlling the temperature of the magnetic material 372 of the heat fixing film 37A as the upper film-like rotating member, as described above with reference to FIG. Fixing film 37 by temperature sensor TS2 as temperature detecting means for detecting the temperature
A temperature (T2 (° C.)) and a temperature (T1 (° C.)) of the heat ray fixing roller 17a by a temperature sensor TS1 as a temperature detecting means for detecting a temperature of the heat ray fixing roller 17a as a lower heat ray fixing rotating member. ) Is measured, and the magnetic material 372 from the reference table corresponding to the temperature (detection temperature) T2 and the temperature (detection temperature) T1 stored in advance in the ROM of the storage unit (ROM, RAM) as a reference table is obtained. The on-off time of a halogen lamp 171g or a xenon lamp (not shown) for heating the coil 373 for heating and the heat ray fixing roller 17a is referred to through a fixing control unit, and the upper heat fixing film 37A and the lower heat ray fixing roller 17a are referred to. Temperature control is performed. Especially for duplex fixing,
Since the temperatures of both the upper heat fixing film 37A and the lower heat ray fixing roller 17a affect the fixing, the upper heat fixing film 37A and the lower heat ray fixing roller 17a are affected.
And both temperature controls are required.

A flat nip portion N is provided between the upper hard roller and the lower soft roller having high elasticity, following the shape of the bottom surface of the magnetic body 372 of the upper heat fixing film 37A.
Is formed, and the toner image is fixed.

Both the heat generated by the magnetic body 372 serving as the induction heating element and the heat generated by the heat rays of the halogen lamp 171g and the xenon lamp (not shown) in the heat ray absorbing layer 171b cause the lower heat ray fixing on both sides. Although instantaneous heating is difficult due to the heating of the roller 17a, a fixing device capable of energy saving and quick start (rapid heating) with a short warm-up time can be realized.

As described above with reference to FIG. 5, the configuration of the heat ray fixing roller 17a is, as shown in the cross section in FIG. 5 (a), as a cylindrical translucent substrate 171a having a thickness of 1 to 20 m.
m, preferably 2-5 mm thick, halogen lamp 171
g or a ceramic material such as sapphire (Al ₂ O ₃ ) or CaF ₂ that transmits heat rays such as infrared rays or far infrared rays from a xenon lamp (not shown) (heat conductivity is (5 to 20) × 10 ⁻ ). ³ J / cm · s · K, specific heat (0.5-2.0) × J / g · K, specific gravity 1.5–3.
0) is mainly used, and a translucent resin using polyimide, polyamide or the like (having a thermal conductivity of (2-4) × 10 ⁻³ J
/ Cm · s · K, specific heat ((1-2) × J / g · K, specific gravity 0.8-1.2), etc. can also be used. For example, as the translucent substrate 171a of the heat ray fixing roller 17a,
When the Pyrex glass (inner diameter 32 mm, outer diameter 40 mm, layer thickness (thickness) 4 mm) (specific heat 0.78 J / g · K, specific gravity 2.32) is used, A-
Heat capacity Q1 per 3 size width (297mm) is about 6
0 cal / deg. Since the wavelength of the heat ray passing through the light-transmitting substrate 171a is 0.1 to 20 μm, and preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler. 1 / wavelength of
2, preferably 1/5 or less, having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles (transmission of infrared rays or far infrared rays including visible light depending on the light source) The transparent substrate 171a may be formed by dispersing fine particles of metal oxide such as ITO, titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. As described above, the translucent substrate 171a does not have good thermal conductivity.

The light-transmitting elastic layer 171d has a thickness of 0.5 to 2 mm.
It is formed of a rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light or infrared rays depending on the light source) using, for example, silicon rubber or fluorine rubber having a thickness of 0 mm, preferably 1 to 5 mm. . Translucent elastic layer 171d
In order to respond to high speed, a method of improving thermal conductivity by mixing a metal oxide powder such as silica, alumina or magnesium oxide as a filler into a base layer (silicone rubber or fluorine rubber) has been adopted. Conductivity (1-3)
× 10 ⁻³ J / cm · s · K, specific heat of (1-2) × J / g
-Use a rubber layer having a K and a specific gravity of 0.9 to 1.0. For example, as the translucent elastic layer 171d of the heat ray fixing roller 17a,
A-3 size width of the light-transmitting elastic layer 171d when silicon rubber having an outer diameter of 50 mm and a layer thickness (thickness) of 5 mm (specific heat is 1.1 J / g · K, specific gravity is 0.91) is used ( 297
The heat capacity Q2 per mm) is about 50 cal / deg. The rubber layer is made of a light-transmitting substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J / cm · s ·
Since it is an order of magnitude lower than K), it functions as a layer having heat insulating properties.
When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a hardness of 40 Hs usually has a hardness of 60 Hs (JIS,
A rubber hardness). Preferred rubber hardness is 5 to 60 Hs. Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is coated with a fluorine-based rubber having a thickness of 20 to 300 μm as an oil-resistant layer to prevent oil swelling. As the silicon rubber of the top layer of the translucent elastic layer 171d, HTV (High Temp) is used.
RTV (RoomTemperature V) which has better releasability than ETERNUS
olcanizing) and LTV (Low Tempe)
(ratio volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, the wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm, and preferably 0.3 to 3 μm. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less including primary and secondary particles,
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
71d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 1 as a heat ray fixing rotating member is provided.
7a is configured as a highly elastic soft roller.

The heat ray absorbing layer 171b is formed of the remaining heat rays emitted from a halogen lamp 171g or a xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d. 90 to 100%, preferably 95 to 100% of the heat rays, which are about 100% of the heat rays transmitted through the 171a and the translucent elastic layer 171d, are absorbed by the heat ray absorbing layer 171b to form a heat ray fixing rotating member capable of instantaneous heating. As described above, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F
e ₂ O ₃ ) or the like, and a heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm is sprayed on the outer side (outer peripheral surface) of the light transmitting elastic layer 171 d. It is formed by coating or the like. Heat ray absorbing layer 171
b has a thermal conductivity of the rubber layer of the translucent elastic layer 171d (having a thermal conductivity of (1-3) × 10 ⁻³ J / cm · s · K and a specific heat of (1-2) × J / g · K, specific gravity is 0.9 to 1.0), and a slightly higher (3 to 10) × 10 ⁻³ J / cm · s · K (specific heat is increased by adding an absorbent such as carbon black). 2.0) × J / g · K, and the specific gravity can be set to (〜0.9). As the heat ray absorbing layer 171b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%,
For example, if it is about 20 to 80%, the heat rays leak, and when the heat ray fixing roller 17a as a heat ray fixing rotating member is used for monochrome image formation due to the leaked heat rays, a specific position of the heat ray fixing roller 17a is determined by filming or the like. When the black toner adheres to the surface of the device, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of the heat rays is further superimposed on the portion to damage the heat ray absorbing layer 171b. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The heat rays transmitted through the heat ray absorbing layer 171
The heat ray absorption rate of the heat ray absorption layer 171b is set to 90 to 100%, which is about 100%, and preferably 95 to 100% so that the heat ray is completely absorbed by b. When the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate due to the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b may be damaged by local heating by the thin film and the strength may be insufficient. If the thickness of the heat ray absorbing layer 171b exceeds 500 μm and is too thick, poor heat conduction or large heat capacity makes rapid heating difficult. By setting the heat ray absorption rate of the heat ray absorption layer 171b to 90 to 100%, which is about 100%, preferably 95 to 100%, or setting the thickness of the heat ray absorption layer 171b to 10 to 500 μm, preferably 20 to 100 μm, Local heat generation in the absorption layer 171b is prevented, and uniform heat generation is performed. Heat ray absorbing layer 1
Since the wavelength of the heat ray projected on 71b is 0.1 to 20 μm, and preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler. / 2, preferably 1/5 or less, including primary and secondary particles, having an average particle size of 1 μm or less, preferably 0.1 μm
Fine particles of metal oxides such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, calcium carbonate, etc. having the following heat ray transmittance (infrared ray or visible ray including visible light depending on the light source) are used as the resin binder. The heat ray absorbing layer 171b may be formed by dispersing 5 to 50% by weight. Thus, the heat ray absorbing layer 171b
Since the heat capacity is reduced so that the temperature rises immediately, the heat ray fixing roller 17a as a heat ray fixing rotating member is used.
This prevents the problem that the temperature is lowered and the fixing unevenness occurs. As the heat ray absorbing layer 171b, carbon black, graphite,
A mixture of iron black (Fe ₃ O ₄ ), various ferrites and their compounds, and powders such as copper oxide, cobalt oxide, and red iron oxide (Fe ₂ O ₃ ) may be used. For example, heat ray fixing roller 1
7a of the heat ray absorbing layer 171b (or the dual-purpose layer 17 described later).
As 1Z), a fluororesin (specific heat: 2.0 J / g · K, specific gravity: 0.9) having a layer thickness (thickness) of 50 μm is applied to the surface (outer peripheral surface) of the light-transmitting elastic layer 171 d having an outer diameter of 50 mm. A of heat ray absorbing layer 171b (or dual-purpose layer 171Z) when used
The heat capacity Q3 per −3 size width (297 mm) is about 1.0 cal / deg. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

Further, a PFA (fluororesin) tube having a thickness of 30 to 100 μm is coated on the outer side (outer peripheral surface) of the heat ray absorbing layer 171b separately from the heat ray absorbing layer 171b to improve the releasability from the toner. Or fluorinated resin (PF
A or PTFE) Release layer 171c coated with a paint of 20 to 30 μm (having a thermal conductivity of (1 to 10) × 10 ⁻³ J / cm.
S · K, specific heat (（2.0) × J / g · K, specific gravity (〜0.9)) (separated type).

Further, as shown in the cross section in FIG. 5B, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (Fe ₂ O ₃ ), etc. Heat-absorbing member mixed with powder of PTFE, and a fluororesin (PFA or PT) that also serves as a binder and a release agent
FE) paint is mixed and mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG.
A heat-fixing rotary member in the form of a roll having elasticity may be formed outside (outer peripheral surface) of the translucent elastic layer 171d formed outside (outer peripheral surface). The thermal conductivity of the dual-purpose layer 171Z is substantially the same as the thermal conductivity of the heat ray absorbing layer 171b.
(3-10) × 10 ⁻³ J / cm · s · K (specific heat
2.0) × J / g · K, and specific gravity is (０．９0.9).
As described above, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the translucent base 171a and the translucent elastic layer 171d are:
In order to completely absorb the heat rays transmitted through the light-transmitting base 171a and the light-transmitting elastic layer 171d, the heat ray absorptivity of the dual-purpose layer 171Z is set to 90 to 100%, which is about 100%, and preferably 95 to 100%. When the heat ray absorptivity in the dual-purpose layer 171Z is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the heat ray fixing rotating member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the heat ray fixing rotating member at a specific position due to, for example, mining, heat is generated from the adhering portion by the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the dual-purpose layer 171Z. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The combined layer 171Z has a heat ray absorptivity of about 100%, which is about 90-100%, preferably 95-1%, so that the heat rays transmitted through the heat ray fixing rotary member are completely absorbed in the heat ray fixing rotating member.
00%. Further, local heat generation in the dual-purpose layer 171Z is also prevented, and uniform heat generation is performed. In addition, the combined use layer 17
Since the wavelength of the heat ray projected on 1Z is 0.1 to 20 μm, preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler, but the particle size is 1 to the wavelength of the heat ray. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less, preferably 0.1 μm or less including primary and secondary particles (infrared ray or visible ray including visible light depending on the light source). The dual-purpose layer 171Z may be formed by dispersing fine particles of a metal oxide such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder.

In the same manner as described above with reference to FIG. 6, if the concentration distribution of the above-described heat ray absorbing member is uniformly provided on the heat ray absorbing layer 171b of the heat ray fixing roller 17a as a roll-shaped rotating member for heat ray fixing, the heat ray at the boundary is formed. Heat is concentrated in the absorption layer 171b, and the heat easily flows to the side of the light-transmitting elastic layer 171d. It is preferable to generate heat inside from the viewpoint of dispersing the heat generation distribution. As shown in the graph (a), the concentration distribution of the heat ray absorbing layer 171b is set such that the interface on the side of the light-transmitting elastic layer 171d adjacent thereto has a low concentration, is gradually inclined toward the outer peripheral surface side, and is gradually increased. (Thickness t of heat ray absorbing layer 171b)
1/3 from the light-transmitting elastic layer 171d side.
(Position of about degree) so as to obtain a concentration that absorbs 100% so as to be saturated. Thereby, the heat ray absorbing layer 171b
As shown in the graph (b), the heat generation distribution due to the absorption of the heat ray at the point has a maximum value near the center of the heat ray absorption layer 171b and a minimum value near the interface and the outer peripheral surface of the heat ray absorption layer 171b. It is formed in a shape. Alternatively, the heat ray absorbing layer 171b
It is preferable to provide a light-transmissive heat-resistant resin (polyimide, fluororesin or silicon resin) with a thickness of 10 to 500 μm, preferably 20 to 100 μm on the interface or the outer peripheral surface of the substrate. Further, it is preferable to suppress heat loss as a member having a lower thermal conductivity than the translucent substrate 171a. This reduces heat generation due to absorption of heat rays at the interface, prevents heat from flowing out, and prevents damage to the adhesive layer and heat ray absorbing layer 171b at the interface. In addition, before the outer peripheral surface side (the heat ray absorbing layer 171).
2/3 from the light-transmitting base 171a side with respect to the thickness t1 of b.
(About ４ of the position) to saturate the concentration distribution from the outer peripheral surface to the outer peripheral surface. Note that a saturated layer may be formed as shown by a dotted line. In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle.

In the same manner as described above with reference to FIG. 7, the outer diameter φ of the cylindrical light-transmitting substrate 171a of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is set to 15 to 15.
A thickness t of 60 mm is used. A thicker thickness t is better in terms of strength, and a thinner thickness is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the thickness t is outside the cylindrical light-transmitting base 171a. The relationship between the diameter φ and the thickness t is 0.02 ≦ t / φ ≦ 0.20, and preferably 0.04 ≦ t / φ ≦ 0.10. When the outer diameter φ of the transparent substrate 171a is 40 mm, the thickness t of the transparent substrate 171a is 0.8 mm ≦ t ≦ 8 m.
m, preferably 1.6 mm ≦ t ≦ 4.0 mm. When t / φ is less than 0.02 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.20, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, depending on the material, a light-transmitting substrate may absorb about 1 to 20% of heat rays, and it is preferable that the substrate be thin as long as the strength can be maintained.

As described above, by using the fixing device 370 of the third example described with reference to FIG. 13, the upper heat fixing film is disposed between the upper hard roller and the lower elastic soft roller. A flat nip portion N is formed following the bottom shape of the magnetic body 372 of the 37A to fix the toner image, and heat of the magnetic body 372 as an induction heating body due to induction heating of the coil 373 and halogen are generated. Lamp 171
Heat generation in the heat ray absorbing layer 171b by the heat rays of the g and xenon lamps (not shown) enables high-speed fixing while saving energy and shortening the warm-up time, and also achieves good fixing properties due to a uniform and stable temperature. The resulting fixing device and image forming apparatus can be obtained. In particular, in the double-sided image forming apparatus described with reference to FIG. 12, high-speed fixing of the surface toner image in the double-sided image formation can be performed while saving energy and shortening the warm-up time, and a good surface toner image can be formed by a uniform and stable temperature. Can be fixed.

Embodiment 4 An image of an embodiment of an image forming apparatus in which the fourth embodiment of the fixing device according to the present invention is applied to the second example of the image forming apparatus described in the second embodiment. FIG. 14 or FIG. 15 and Embodiment 1 regarding the forming process and each mechanism.
This will be described with reference to FIGS. FIG.
FIG. 15 is a sectional configuration diagram of a color image forming apparatus showing an embodiment of a fourth example of the image forming apparatus according to the present invention, and FIG. 15 is a sectional configuration diagram of a fourth example of a fixing device according to the present invention. It is.

According to FIG. 14, the photosensitive drum 10 as an image carrier is provided on the outer periphery of a cylindrical base formed of a light transmitting member such as glass or light transmitting acrylic resin. It is formed by forming a conductive layer and a photoconductor layer of an organic photosensitive layer (OPC).

The photosensitive drum 10 is rotated clockwise as indicated by an arrow in FIG. 14 by a power from a driving source (not shown) while the light-transmitting conductive layer is grounded.

In the present invention, the exposure beam for image exposure is
The photoconductor layer of the photoconductor drum 10, which is the image forming point, only needs to have an exposure light amount of a wavelength that can provide an appropriate contrast with respect to the light attenuation characteristic (photocarrier generation) of the photoconductor layer. . Therefore, the light transmittance of the light-transmitting substrate of the photosensitive drum 10 in the present embodiment does not need to be 100%, and may have a characteristic of absorbing a certain amount of light when transmitting the exposure beam. Good. The point is that any suitable contrast can be provided. As a material of the light-transmitting substrate, an acrylic resin, particularly one obtained by polymerizing a methyl methacrylate monomer, is preferably used because of its excellent light-transmitting properties, strength, accuracy, surface properties, etc. Various translucent resins such as acryl, fluorine, polyester, polycarbonate, polyethylene terephthalate and the like used for the above can be used. Further, as long as it has a light-transmitting property with respect to the exposure light, it may be colored. As the light-transmitting conductive layer, indium tin oxide (I
TO), tin oxide, lead oxide, indium oxide, copper iodide, or a metal thin film of Au, Ag, Ni, Al, or the like that maintains light transmissivity. Reactive deposition method, various sputtering methods, various CV
D method, dip coating method, spray coating method and the like can be used.
Various organic photosensitive layers (OPC) can be used as the photoconductor layer.

The organic photosensitive layer serving as the photosensitive layer of the photoconductor layer includes a charge generation layer (CGL) mainly composed of a charge generation substance (CGM) and a charge transport layer (CTM) mainly composed of a charge transport substance (CTM). And CTL). An organic photosensitive layer having a two-layer structure has high durability as an organic photosensitive layer due to its thick CTL and is suitable for the present invention.
The organic photosensitive layer may have a single layer structure containing a charge generation material (CGM) and a charge transport material (CTM) in one layer. ,
Usually, a binder resin is contained.

A scorotron charger 11 as a charging unit described below, and an exposure optical system 1 as an image writing unit will be described.
2. The developing device 13 as a developing unit is prepared for an image forming process for each color of yellow (Y), magenta (M), cyan (C) and black (K), respectively. Are arranged in the order of Y, M, C, and K with respect to the rotation direction of the photosensitive drum 10 indicated by the arrow in FIG.

Scorotron charger 11 as charging means
Is mounted so as to face and be close to the photosensitive drum 10 in a direction perpendicular to the moving direction of the photosensitive drum 10 as an image forming body (the direction perpendicular to the paper of FIG. 14). A control grid (unsigned) maintained at a predetermined potential with respect to the layer;
As a, for example, a sawtooth electrode is used, and a charging action (in this embodiment, negative charging) is performed by corona discharge having the same polarity as that of the toner, thereby giving a uniform potential to the photosensitive drum 10. As the corona discharge electrode 11a, a wire electrode or a needle electrode may be used.

The exposure optical system 12 for each color is a linear exposure element (LED) in which a plurality of LEDs (light emitting diodes) as light emitting elements for image exposure light are arranged in an array parallel to the axis of the photosensitive drum 10. (Not shown) and a selfoc lens (not shown) as an equal-magnification imaging element are configured as an exposure unit attached to a holder. Cylindrical holding member 2
At 0, the exposure optical system 12 for each color is attached and housed inside the base of the photosensitive drum 10. In addition, as the exposure element, a linear element in which a plurality of light emitting elements such as FL (phosphor emission), EL (electroluminescence), and PL (plasma discharge) are arranged in an array is used.

The exposure optical system 12 as an image writing means for each color moves the exposure position on the photosensitive drum 10 between the scorotron charger 11 and the developing device 13 with respect to the developing device 13. It is arranged inside the photoconductor drum 10 in a state provided on the upstream side in the rotation direction of the drum 10.

The exposure optical system 12 performs image processing based on image data of each color sent from a separate computer (not shown) and stored in the memory, and then performs image processing on the uniformly charged photosensitive drum 10. Exposure is performed to form a latent image on the photosensitive drum 10. The emission wavelength of the light-emitting element used in this embodiment is usually 6 for the toners of Y, M, and C, which have high translucency.
The wavelength in the range of 80 to 900 nm is good, but the wavelength may be shorter than this, since the color toner does not have sufficient translucency since image exposure is performed from the back surface.

The developing device 13 as a developing means for each color includes
Inside yellow (Y), magenta (M), cyan (C)
Alternatively, it contains a black (K) two-component (or one-component) developer and is formed of, for example, a cylindrical nonmagnetic stainless steel or aluminum material having a thickness of 0.5 to 1 mm and an outer diameter of 15 to 25 mm, respectively. Developing sleeve 13a.

In the developing region, the developing sleeve 13a is kept in non-contact with the photosensitive drum 10 by a contact roller (not shown) with a predetermined gap, for example, 100 to 1000 μm, between the developing sleeve 13a and the rotating direction of the photosensitive drum 10. At the closest position, the developing sleeve 13a rotates in the forward direction. At the time of development, a DC voltage of the same polarity as the toner (in the present embodiment, a negative polarity) or a DC voltage superimposed on the DC voltage is applied to the developing sleeve 13a. By applying a bias voltage, non-contact reversal development is performed on the exposed portion of the photosensitive drum 10. At this time, the precision of the development interval needs to be about 20 μm or less in order to prevent image unevenness.

As described above, the developing device 13 transfers the electrostatic latent image formed on the photosensitive drum 10 by charging by the scorotron charger 11 and image exposure by the exposure optical system 12 in a non-contact state to the photosensitive drum. Reversal development is performed with toner having the same polarity as the charge polarity of No. 10 (in the present embodiment, the photosensitive drum is negatively charged, and the toner has a negative polarity).

When the image carrier driving motor (not shown) is started by the start of image formation, the photosensitive drum 10 is moved to the position shown in FIG.
, And at the same time, application of a potential to the photosensitive drum 10 is started by the charging action of the Y scorotron charger 11. After a potential is applied to the photosensitive drum 10, image writing is started by the first color signal, that is, an electric signal corresponding to the Y image data in the Y exposure optical system 12, and the rotation of the photosensitive drum 10 causes the image writing to start. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface. This latent image is a Y developing device 1
3 and the photosensitive drum 1
A yellow (Y) toner image is formed on 0.

Next, the photoreceptor drum 10 places an M scorotron charger 11 on the yellow (Y) toner image.
A potential is applied by the charging action of the M exposure optical system 12
Of the yellow (Y) toner image by the non-contact reversal development by the M developing device 13 is performed. A magenta (M) toner image is formed on the image.

By the same process, the cyan (C) toner image corresponding to the third color signal is further obtained by the C scorotron charger 11, the exposure optical system 12, and the developing device 13, and the K scorotron charger 11 , Exposure optical system 1
A black (K) toner image corresponding to the fourth color signal is sequentially superimposed and formed by the second and developing units 13, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10. You.

As described above, in the present embodiment, Y, M,
The exposure of the organic photosensitive layer of the photoconductor drum 10 by the C and K exposure optical systems 12 is performed through a transparent substrate from the inside of the photoconductor drum 10. Therefore, the exposure (image writing) of the image corresponding to the second, third and fourth color signals can form an electrostatic latent image without being shielded by the previously formed toner image. Exposure may be performed from the outside of the photoreceptor drum 10, although it is preferable.

On the other hand, the recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a half-moon-shaped feed roller (no code), and is fed by a feed roller (no code). Timing roller 15b
Transported to

The recording paper P is synchronized with the color toner image carried on the photosensitive drum 10 by the driving of the timing roller 15b, and is charged by the paper charger 150 as a transfer material charging means, so that the transport belt 14A is charged. And is fed to the transfer area. The recording paper P, which has been closely transported by the transport belt 14A, is rotated around the photosensitive drum 10 by a transfer unit 14c as a transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied in a transfer area. The color toner images on the surface are collectively transferred to the recording paper P.

The recording paper P on which the color toner image has been transferred is
The charge is removed by a transfer material removing unit 14h as a transfer material removing unit, separated from the transport belt 14A, and transported to the fixing device 470 of the fourth example.

The fixing device 470 of the fourth example includes a heat-fixing roller 17a serving as an upper roll-shaped hot-wire fixing rotating member for fixing a color toner image, and a magnetic body 472 serving as an induction heating element. A heat-fixing film 47A as a lower film-shaped rotating member is provided. In the center of the heat-ray fixing roller 17a, a halogen lamp 171g or xenon that emits heat rays such as infrared rays or far-infrared rays including visible light depending on a light source is provided. A lamp (not shown) or the like is provided as a heat ray irradiation unit.

Heat ray fixing roller 17a and heat fixing film 4
7A, the recording paper P is nipped by a nip N, and the color toner image on the recording paper P is fixed by applying heat and pressure. Is discharged to the tray at the top of the device.

The toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is transferred to a cleaning blade 19 provided in a cleaning device 19 as an image forming body cleaning means.
Cleaning is performed by a. The photosensitive drum 10 from which the residual toner has been removed is uniformly charged by the scorotron charger 11, and enters the next image forming cycle.

As shown in FIG. 15, the fixing device 470 according to the fourth embodiment has a heat ray fixing roller 17a as an upper roll-shaped heat ray fixing rotating member for fixing a color toner image.
And a heat-fixing film 47A as a lower film-shaped rotating member, and is formed between the heat-ray fixing roller 17a as a soft roller having elasticity and the heat-fixing film 47A as a hard roller. 30mm width
Hereinafter, preferably in a wide nip portion N of 10 mm or more,
The recording paper P that enters the nip portion N and passes through the nip portion N is nipped, and the toner image on the recording paper P is fixed by applying heat and pressure.

A heat ray fixing roller 17a as a heat ray fixing rotating member for fixing a toner image on a transfer material is provided on a cylindrical light-transmitting substrate 171a and on the outside (outer peripheral surface) of the light-transmitting substrate 171a. Translucent elastic layer 171d and heat ray absorbing layer 17
1b and a release layer 171c are provided in that order as a soft roller. Halogen lamp 171 which is a heat ray irradiating means for emitting a heat ray such as infrared ray or far infrared ray including visible light depending on a light source is provided in the center of the interior of the transparent substrate 171a.
g or a xenon lamp (not shown). The heat ray fixing roller 17a as a heat ray fixing rotating member is configured as a highly elastic soft roller as described later.
A heat ray emitted from the halogen lamp 171g or a xenon lamp (not shown) is absorbed by the heat ray absorbing layer 171b to form a roll-shaped heat ray fixing rotating member capable of rapid heating. Preferably, a heat uniformizing roller TR4 is provided on the surface of the heat ray fixing roller 17a. The heat uniformizing roller TR4 using a heat roller or a metal roller member having good thermal conductivity such as an aluminum material or a stainless steel material. Heat ray fixing roller 17a heated by heat ray absorbing layer 171b
The heat generation temperature distribution on the peripheral surface is made uniform. Heat uniformizing roller T
By R4, the temperature unevenness in the vertical and horizontal directions of the heat ray fixing roller 17a due to the passage of the transfer material is made uniform. TS1 is a temperature sensor attached to the upper heat ray fixing roller 17a and serving as a temperature detecting unit using a contact type thermistor for performing temperature control. As the temperature sensor TS1, a non-contact type sensor can be used in addition to a contact type sensor.

The lower heat fixing film 47A is, for example, a thin fixing film 171 having a thickness of 40 to 100 μm.
A magnetic body 472 as an induction heating element, and a magnetic body 472
As a hard roller with a coil 373 for induction heating. TS2 is the lower heat fixing film 4
This is a temperature sensor which is a temperature detecting means mounted on the back surface (opposite side of the nip portion N) of the magnetic body 472 of 7A, for example, a contact type thermistor for performing temperature control. As the temperature sensor TS2, a non-contact type sensor can be used in addition to a contact type sensor.

The heat capacity of the fixing film 171 is about 1/20 that of the heat ray fixing roller 17a, so that a quick start with almost zero warm-up is possible. The magnetic body 472 serves as a running guide for the rotating fixing film 171, while being pressed against the heat ray fixing roller 17 a. The fixing film 171 is made of a magnetic material 472.
The heat ray fixing roller 17 loosely fits into the
The rotation is driven by the surface frictional force a. Heat fixing film 4
Since 7A has a small heat capacity, the heat of the heat ray fixing roller 17a is hardly removed.

The magnetic material 472 is a metal base such as alumina or iron oxide provided with a resistor and an overcoat glass by thick film printing.
Lowering the thermal resistance between them.

The structure of the fixing film 171 includes a base material 171A, a conductive layer 171B, and a surface release layer 171C, as described above with reference to FIG.

The base material 171A is preferably a polyimide resin having excellent strength and dimensional stability at high temperatures, and preferably has a thickness of about 40 to 100 μm. By increasing the thickness to about 40 μm, the strength and rigidity are increased, and the end of the fixing film 171 during rotation can be regulated without buckling. On the other hand, if the thickness is more than 100 μm, the heat conduction becomes poor, and the heat conduction becomes large, so that it becomes difficult to heat up instantaneously and the electric power used increases. It is preferable to provide a surface release layer 171C, for example, a layer of a fluororesin (PFA or PTFE) to prevent offset. The conductive layer 171B is provided and grounded in order to eliminate the influence of the triboelectric charge generated by the sliding of. Also, a conductive filler is inserted in the surface release layer 171C to reduce the resistance so as to release the charged charges peeled off from the rear end of the recording paper P in a low humidity environment, thereby preventing the offset. However, if the resistance value is too low, the transfer charge leaks to cause an offset, so that 2 × 10 ^{10 to} 5 × 10 ¹¹ Ω / cm ²
Is preferable.

The temperature control of the upper heat ray fixing roller 17a and the lower heat fixing film 47A is performed by detecting the temperature of the heat ray fixing roller 17a serving as the upper heat ray fixing rotating member, as described above with reference to FIG. The temperature (T1) of the heat ray fixing roller 17a by the temperature sensor TS1 as a temperature detecting means.
(° C.)) and the temperature (T2 (° C.)) of the heat fixing film 47A by the temperature sensor TS2 as a temperature detecting means for detecting the temperature of the magnetic body 472 of the heat fixing film 47A as the lower rotating member. And a halogen lamp 171g or a xenon lamp from a reference table corresponding to the temperature (detection temperature) T1 and the temperature (detection temperature) T2 stored in advance in a ROM of a storage unit (ROM, RAM) as a reference table. (Not shown) and magnetic body 472
The on-off time of the coil 373 for heating the heating roller 373 is referred to through the fixing control unit, and the upper heat ray fixing roller 17a
Then, the temperature of the lower heat fixing film 47A is controlled. In particular, heating control is performed from both sides in order to shorten the warm-up time.
High-precision temperature control is performed. In particular, in the case of fixing a color toner image, since both the temperature of the upper heat ray fixing roller 17a and the temperature of the lower heat fixing film 47A affect glossiness and color, both temperature controls are required.

A nip portion having a convex upper side following the upper surface of the magnetic body 472 of the lower heat fixing film 47A between the upper elastic soft roller and the lower hard roller. N is formed, and the toner image is fixed.

The heat generation in the heat absorbing layer 171b by the heat rays of the halogen lamp 171g or the xenon lamp (not shown) and the heat generation of the magnetic body 472 as the induction heating element save energy and quick start (rapid heating) with a short warm-up time. A possible fixing device becomes possible.

As described above with reference to FIG. 5, the structure of the heat ray fixing roller 17a is, as shown in a cross section in FIG. 5 (a), a cylindrical light transmitting substrate 171a having a thickness of 1 to 20 m.
m, preferably 2-5 mm thick, halogen lamp 171
g or a ceramic material such as sapphire (Al ₂ O ₃ ) or CaF ₂ that transmits heat rays such as infrared rays or far infrared rays from a xenon lamp (not shown) (heat conductivity is (5 to 20) × 10 ⁻ ). ³ J / cm · s · K, specific heat (0.5-2.0) × J / g · K, specific gravity 1.5–3.
0) is mainly used, and a translucent resin using polyimide, polyamide or the like (having a thermal conductivity of (2-4) × 10 ⁻³ J
/ Cm · s · K, specific heat ((1-2) × J / g · K, specific gravity 0.8-1.2), etc. can also be used. For example, as the translucent substrate 171a of the heat ray fixing roller 17a,
When the Pyrex glass (inner diameter 32 mm, outer diameter 40 mm, layer thickness (thickness) 4 mm) (specific heat 0.78 J / g · K, specific gravity 2.32) is used, A-
Heat capacity Q1 per 3 size width (297mm) is about 6
0 cal / deg. Since the wavelength of the heat ray passing through the light-transmitting substrate 171a is 0.1 to 20 μm, and preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler. 1 / wavelength of
2, preferably 1/5 or less, having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles (transmission of infrared rays or far infrared rays including visible light depending on the light source) The transparent substrate 171a may be formed by dispersing fine particles of metal oxide such as ITO, titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. As described above, the translucent substrate 171a does not have good thermal conductivity.

The light-transmitting elastic layer 171d has a thickness of 0.5 to 2 mm.
It is formed of a rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light or infrared rays depending on the light source) using, for example, silicon rubber or fluorine rubber having a thickness of 0 mm, preferably 1 to 5 mm. . Translucent elastic layer 171d
In order to respond to high speed, a method of improving thermal conductivity by mixing a metal oxide powder such as silica, alumina or magnesium oxide as a filler into a base layer (silicone rubber or fluorine rubber) has been adopted. Conductivity (1-3)
× 10 ⁻³ J / cm · s · K, specific heat of (1-2) × J / g
-Use a rubber layer having a K and a specific gravity of 0.9 to 1.0. For example, as the translucent elastic layer 171d of the heat ray fixing roller 17a,
A-3 size width of the light-transmitting elastic layer 171d when silicon rubber having an outer diameter of 50 mm and a layer thickness (thickness) of 5 mm (specific heat is 1.1 J / g · K, specific gravity is 0.91) is used ( 297
The heat capacity Q2 per mm) is about 50 cal / deg. The rubber layer is made of a light-transmitting substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J / cm · s ·
Since it is an order of magnitude lower than K), it functions as a layer having heat insulating properties.
When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a hardness of 40 Hs usually has a hardness of 60 Hs (JIS,
A rubber hardness). Preferred rubber hardness is 5 to 60 Hs. Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is coated with a fluorine-based rubber having a thickness of 20 to 300 μm as an oil-resistant layer to prevent oil swelling. As the silicon rubber of the top layer of the translucent elastic layer 171d, HTV (High Temp) is used.
RTV (RoomTemperature V) which has better releasability than ETERNUS
olcanizing) and LTV (Low Tempe)
(ratio volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, the wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm, and preferably 0.3 to 3 μm. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less including primary and secondary particles,
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
71d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 1 as a heat ray fixing rotating member is provided.
7a is configured as a highly elastic soft roller.

As the heat ray absorbing layer 171b, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d are used as the heat transmitting layer 171b. 90 to 100%, preferably 95 to 100% of the heat rays, which are about 100% of the heat rays transmitted through the 171a and the translucent elastic layer 171d, are absorbed by the heat ray absorbing layer 171b to form a heat ray fixing rotating member capable of instantaneous heating. As described above, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F
e ₂ O ₃ ) or the like, and a heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm is sprayed on the outer side (outer peripheral surface) of the light transmitting elastic layer 171 d. It is formed by coating or the like. Heat ray absorbing layer 171
b has a thermal conductivity of the rubber layer of the translucent elastic layer 171d (having a thermal conductivity of (1-3) × 10 ⁻³ J / cm · s · K and a specific heat of (1-2) × J / g · K, specific gravity is 0.9 to 1.0), and a slightly higher (3 to 10) × 10 ⁻³ J / cm · s · K (specific heat is increased by adding an absorbent such as carbon black). 2.0) × J / g · K, and the specific gravity can be set to (〜0.9). As the heat ray absorbing layer 171b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%,
For example, if it is about 20 to 80%, the heat rays leak, and when the heat ray fixing roller 17a as a heat ray fixing rotating member is used for monochrome image formation due to the leaked heat rays, a specific position of the heat ray fixing roller 17a is determined by filming or the like. When the black toner adheres to the surface of the device, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of the heat rays is further superimposed on the portion to damage the heat ray absorbing layer 171b. In addition, when used for forming a color image, the absorption efficiency of the color toner is generally low, and there is a difference in the absorption efficiency between the color toners, resulting in poor fixing or uneven fixing. Therefore, light is emitted from the halogen lamp 171g or a xenon lamp (not shown), and the light-transmitting base 171a and the light-transmitting elastic layer 171 are emitted.
The remaining heat rays absorbed by the light-transmitting substrate 171a and the light-transmitting elastic layer 171d are the remaining heat rays absorbed by the heat ray absorbing layer 1.
The heat ray absorption rate of the heat ray absorbing layer 171b is set to 90 to 100%, which is substantially 100%, and preferably 95 to 100% so that the heat ray is completely absorbed by 71b. Thus, the color toner, which is difficult to fix by heat rays due to the difference in spectral characteristics, is favorably melted. Particularly, in the color image formation in FIG. 14, it is difficult to fix by heat rays due to the difference in spectral characteristics. The superimposed color toner image on the transfer material having a thick toner layer is fused well. Further, when the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate due to the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b is damaged by local heating by the thin film and the cause of the insufficient strength. When the thickness of the heat ray absorbing layer 171b exceeds 500 μm and is too thick, poor heat conduction or large heat capacity makes rapid heating difficult. The heat ray absorption rate of the heat ray absorption layer 171b is about 100%, which is 9%.
By setting the thickness of the heat ray absorbing layer 171b to 0 to 100%, preferably 95 to 100%, or setting the thickness of the heat ray absorbing layer 171b to 10 to 500 μm, preferably 20 to 100 μm,
Local heat generation in 1b is prevented, and uniform heat generation is performed. Since the wavelength of the heat ray projected on the heat ray absorbing layer 171b is 0.1 to 20 μm, preferably 0.3 to 3 μm, a hardness or thermal conductivity modifier is added as a filler. 1/2 of the wavelength of the heat ray, preferably 1/5
Titanium oxide having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles, and having a transmittance of infrared rays or infrared rays containing visible light or far infrared rays depending on the light source. The heat ray absorbing layer 171b may be formed by dispersing fine particles of a metal oxide such as aluminum, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder in an amount of 5 to 50% by weight. In this way, the heat capacity of the heat ray absorbing layer 171b is reduced so that the temperature rises immediately. Therefore, the temperature of the heat ray fixing roller 17a as a heat ray fixing rotating member is lowered, and the fixing unevenness occurs. To prevent. Heat ray absorbing layer 171b
As for silicone rubber or fluoro rubber with elasticity,
Carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and compounds thereof, and a mixture of powders such as copper oxide, cobalt oxide, and red iron oxide (Fe ₂ O ₃ ) may be used. For example, the heat ray absorbing layer 171b of the heat ray fixing roller 17a
(Or a combined layer 171Z described later) with an outer diameter of 50 m.
m on a surface (outer peripheral surface) of the light-transmitting elastic layer 171d, a fluororesin having a layer thickness (thickness) of 50 μm (specific heat 2.0 J / g ·
K, specific gravity 0.9) when the heat ray absorbing layer 171b is used.
A-3 size width (297 m) of (or combined layer 171Z)
The heat capacity Q3 per m) is about 1.0 cal / deg. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

Further, a PFA (fluororesin) tube having a thickness of 30 to 100 μm is coated on the outside (outer peripheral surface) of the heat ray absorbing layer 171b separately from the heat ray absorbing layer 171b to improve the releasability from the toner. Or fluororesin (PF
A or PTFE) Release layer 171c coated with a paint of 20 to 30 μm (having a thermal conductivity of (1 to 10) × 10 ⁻³ J / cm.
S · K, specific heat (（2.0) × J / g · K, specific gravity (〜0.9)) (separated type).

Further, as shown in the cross section in FIG. 5B, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (Fe ₂ O ₃ ) and the like Heat-absorbing member mixed with a powder of PTFE, and a fluororesin (PFA or PT
FE) paint is mixed and mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG.
A heat-fixing rotary member in the form of a roll having elasticity may be formed outside (outer peripheral surface) of the translucent elastic layer 171d formed outside (outer peripheral surface). The thermal conductivity of the dual-purpose layer 171Z is substantially the same as the thermal conductivity of the heat ray absorbing layer 171b.
(3-10) × 10 ⁻³ J / cm · s · K (specific heat
2.0) × J / g · K, and specific gravity is (０．９0.9).
As described above, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the translucent base 171a and the translucent elastic layer 171d are:
In order to completely absorb the heat rays transmitted through the light-transmitting base 171a and the light-transmitting elastic layer 171d, the heat ray absorptivity of the dual-purpose layer 171Z is set to 90 to 100%, which is about 100%, and preferably 95 to 100%. When the heat ray absorptivity in the dual-purpose layer 171Z is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the heat ray fixing rotating member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the heat ray fixing rotating member at a specific position due to, for example, mining, heat is generated from the adhering portion by the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the dual-purpose layer 171Z. When used for color image formation, the color toner absorption efficiency is generally low,
In addition, since there is a difference in the absorption efficiency between the color toners, a fixing failure occurs or fixing unevenness occurs. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The combined layer 171Z has a heat ray absorptivity of about 90% to 100%, preferably about 100%, preferably 9 so that the heat rays transmitted through the heat ray fixing rotary member are completely absorbed in the heat ray fixing rotating member.
5 to 100%. Further, local heat generation in the dual-purpose layer 171Z is also prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the dual-purpose layer 171Z is 0.1 to 20 μm.
m, preferably 0.3 to 3 μm, so that a filler for adjusting hardness or thermal conductivity is added as a filler. 2
The average particle size including the secondary particles is 1 μm or less, preferably 0.1 μm or less.
Fine particles of metal oxide such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, calcium carbonate, etc. having a heat ray transmission of 1 μm or less (infrared ray or visible ray including visible light depending on the light source) are used as resin binder. May be formed to form the dual-purpose layer 171Z.

As described above with reference to FIG. 6, if the concentration distribution of the above-described heat ray absorbing member is uniformly provided on the heat ray absorbing layer 171b of the heat ray fixing roller 17a as a roll-shaped rotating member for fixing the heat ray, the heat ray at the boundary is formed. Heat is concentrated in the absorption layer 171b, and the heat easily flows to the light-transmitting elastic layer 171d side. Therefore, the heat ray absorption layer 171b may be formed by using a lower heat conductive member than the light-transmitting substrate 171a or by providing a concentration distribution. It is preferable to generate heat inside from the viewpoint of dispersing the heat generation distribution. As shown in the graph (a), the concentration distribution of the heat ray absorbing layer 171b is set such that the interface on the side of the light-transmitting elastic layer 171d adjacent thereto has a low concentration, is gradually inclined toward the outer peripheral surface side, and is gradually increased. (Thickness t of heat ray absorbing layer 171b)
1/3 from the light-transmitting elastic layer 171d side.
(Position of about degree) so as to obtain a concentration that absorbs 100% so as to be saturated. Thereby, the heat ray absorbing layer 171b
As shown in the graph (b), the heat generation distribution due to the absorption of the heat ray at the point has a maximum value near the center of the heat ray absorption layer 171b and a minimum value near the interface and the outer peripheral surface of the heat ray absorption layer 171b. It is formed in a shape. Alternatively, the heat ray absorbing layer 171b
It is preferable to provide a light-transmissive heat-resistant resin (polyimide, fluororesin or silicon resin) with a thickness of 10 to 500 μm, preferably 20 to 100 μm on the interface or the outer peripheral surface of the substrate. Further, it is preferable to suppress heat loss as a member having a lower thermal conductivity than the translucent substrate 171a. This reduces heat generation due to absorption of heat rays at the interface, prevents heat from flowing out, and prevents damage to the adhesive layer and heat ray absorbing layer 171b at the interface. In addition, before the outer peripheral surface side (the heat ray absorbing layer 171).
2/3 from the light-transmitting base 171a side with respect to the thickness t1 of b.
(About ４ of the position) to saturate the concentration distribution from the outer peripheral surface to the outer peripheral surface. Note that a saturated layer may be formed as shown by a dotted line. In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle.

In the same manner as described above with reference to FIG. 7, the outer diameter φ of the cylindrical light-transmitting base 171a of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is 15 to
A thickness t of 60 mm is used. A thicker thickness t is better in terms of strength, and a thinner thickness is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the thickness t is outside the cylindrical light-transmitting base 171a. The relationship between the diameter φ and the thickness t is 0.02 ≦ t / φ ≦ 0.20, and preferably 0.04 ≦ t / φ ≦ 0.10. When the outer diameter φ of the transparent substrate 171a is 40 mm, the thickness t of the transparent substrate 171a is 0.8 mm ≦ t ≦ 8 m.
m, preferably 1.6 mm ≦ t ≦ 4.0 mm. When t / φ is less than 0.02 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.20, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, depending on the material, a light-transmitting substrate may absorb about 1 to 20% of heat rays, and it is preferable that the substrate be thin as long as the strength can be maintained.

As described above, by using the fixing device 470 of the fourth example described with reference to FIG. 15, the lower heat fixing is provided between the upper elastic soft roller and the lower hard roller. A nip portion N having a convex upper side is formed according to the circular upper surface shape of the magnetic body 472 of the film 47A, and the toner image is fixed.
Heat absorbing layer 1 by the heat rays of a xenon lamp (not shown)
Both the heat generated by the heat generating member 71b and the heat generated by the magnetic body 472 serving as the induction heating element, particularly, the heat generated by the lower magnetic body 472 generates the heat ray absorbing layer 1 of the upper heat ray fixing roller 17a.
It is possible to raise the temperature of the 71b quickly, thereby enabling high-speed fixing while saving energy and shortening the warm-up time, and an image forming apparatus capable of obtaining a good fixing property with a uniform and stable temperature. In particular, by fixing the toner image with the upper elastic roller (heat ray fixing roller 17a) having high elasticity, high-quality (good fixing performance) fixing is performed.

Embodiment 5 A fifth embodiment of the fixing apparatus according to the present invention and an embodiment of an image forming apparatus in which the fixing apparatus is applied to the first example of the image forming apparatus described in the first embodiment. The image forming process and each mechanism will be described with reference to FIGS. 16 to 19 and FIGS. 2, 4 to 8 described in the first embodiment. FIG. 16 is a sectional configuration diagram of an image forming apparatus showing an embodiment of a fifth example of the image forming apparatus according to the present invention, and FIG. 17 is a sectional configuration of a fifth example of a fixing device according to the present invention. FIG. 18 is a diagram illustrating a layer configuration and a function of the fixing roller member, and FIG. 19 is a diagram illustrating a method of holding the fixing roller member. In the following description of the fifth embodiment of the image forming apparatus, the surface of the transfer material supported and conveyed by the intermediate transfer member on the side facing the image carrier is the front surface, and the other surface, that is, the intermediate transfer member Is referred to as a back surface, an image transferred to the front surface of the transfer material is referred to as a front image, and an image transferred to the back surface of the transfer material is referred to as a back image.

In FIG. 16, 10 is a photosensitive drum as an image carrier, 11 is a scorotron charger as a charging means for each color, 12 is an exposure optical system as an image writing means for each color, and 13 is an exposure optical system for each color. A developing device 14a, an intermediate transfer belt 14a as an intermediate transfer member, and 14b transferring a toner image on the image carrier to the surface of the intermediate transfer member and the transfer material 1
A primary transfer device as a secondary transfer device; 14g, a secondary transfer device as a secondary transfer device for transferring the toner image on the intermediate transfer member to the back surface of the transfer material; 150, a paper charger as a transfer material charging device;
14h is a transfer material static eliminator as a transfer material static elimination means, 160 is a separation claw 210 as a claw member and a spur 162 as a spur member.
Is a fixing device of the fifth example.

The photosensitive drum 10 serving as an image carrier has a transparent conductive layer, a, on the outer periphery of a cylindrical base formed of a transparent member such as optical glass or transparent acrylic resin.
A photosensitive layer such as an Si layer or an organic photosensitive layer (OPC). The conductive layer is grounded. It is rotated at a linear speed of 400 mm / sec.

The toner image forming means for forming a toner image on the image carrier is a scorotron charger 11, which is a charging means.
It comprises a laser exposure optical system 120 as an image writing unit and a developing unit 13 as a developing unit.

Scorotron charger 11 as charging means
Is a control grid maintained at a predetermined potential (unsigned)
And a discharge electrode 11a formed of, for example, a sawtooth electrode,
It is attached to face the photosensitive layer of the photosensitive drum 10 and is charged by corona discharge having the same polarity as the toner (in the present embodiment, the polarity of the toner used is set to minus polarity.
In the present embodiment, the scorotron charger 11 serving as a charging unit performs negative charging (to charge the photosensitive drum 10 uniformly). As the discharge electrode 11a, a wire electrode or a needle electrode may be used.

Laser exposure optical system 12 as image writing means
Reference numeral 0 denotes a semiconductor laser as a light emitting element (not shown), a rotary polygon mirror 120b for rotating and scanning a laser beam emitted from the semiconductor laser, an fθ lens 120c, and a reflection mirror 12
The laser beam emitted from the semiconductor laser is rotationally scanned by a rotating polygon mirror 120b, and is read by a separate image reading device onto the rotating photosensitive drum 10 via an fθ lens 120c and a reflecting mirror 120d. Then, an image is written on the photosensitive layer of the photosensitive drum 10 according to the image data stored in the memory, and an electrostatic latent image is formed on the photosensitive drum 10. It is necessary to change the image data so that the image data corresponding to the front image and the image data corresponding to the back image are mirror images of each other.

The developing device 13 as a developing means keeps a predetermined gap with respect to the peripheral surface of the photosensitive drum 10 and rotates in a forward direction with respect to the rotating direction of the photosensitive drum 10 at a developing position. A developing sleeve 13a formed of a cylindrical nonmagnetic stainless steel or aluminum material having an outer diameter of 15 to 25 mm, and a one-component or two-component developer of black (K) is accommodated inside the developing device 13 are doing. The developing sleeve 13a of the developing device 13 is provided with a predetermined gap, for example, 100 to
The developer on the developing sleeve 13a having a layer thickness of 80 to 300 μm is kept out of contact with the photosensitive drum 10 with a gap of 500 μm, and a developing bias in which a DC voltage and an AC voltage are superimposed is applied to the developing sleeve 13a. As a result, non-contact reversal development is performed, and a toner image is formed on the photosensitive drum 10.

Intermediate transfer belt 14a as an intermediate transfer member
Preferably has a volume resistivity of 10 ⁹ Ω · cm or more,
It is an endless belt of less than ¹² Ωcm, for example, a modified polyimide, a thermosetting polyimide, an ethylene-tetrafluoroethylene copolymer, polyvinylidene fluoride, a thickness of 0.1 to 0.1 in which a conductive material is dispersed in an engineering plastic such as nylon alloy. It is a seamless belt having a two-layer structure in which a 1.0 mm semiconductive film substrate is coated with a fluorine coating having a thickness of 5 to 50 μm, preferably as a toner filming preventing layer. In addition, as the base of the intermediate transfer belt 14a, a semiconductive rubber belt having a thickness of 0.5 to 2.0 mm in which a conductive material is dispersed in silicon rubber or urethane rubber or the like can be used. The intermediate transfer belt 14a includes a driving roller 1 that is a roller member.
4d, the secondary transfer opposing roller 14j, the driven roller 14e, and the tension roller 14i, and are rotated counterclockwise as indicated by the arrow in FIG. The driven roller 14e, the secondary transfer opposing roller 14j, and the driving roller 14d are rotated at a fixed position, and the tension roller 14i is movably supported and rotated by an elastic force such as a spring (not shown). The drive roller 14d is rotated by a drive from an intermediate transfer member drive motor (not shown), and drives and rotates the intermediate transfer belt 14a. The rotation of the intermediate transfer belt 14a causes the secondary transfer opposing roller 14j, the driven roller 14e, and the tension roller 14i to be driven and rotated. The slack of the rotating intermediate transfer belt 14a is tensioned by the tension roller 14i. The intermediate transfer belt 14a is driven
The recording paper P, which is a transfer material, is supplied to a position where the recording paper P is stretched around e, and is supported and conveyed by the intermediate transfer belt 14a. The recording paper P is separated from the intermediate transfer belt 14a at a curvature portion KT at the end of the intermediate transfer belt 14a stretched around the driving roller 14d on the fixing device 570 side.

A primary transfer device 14b as a primary transfer means for transferring the toner image on the image carrier to the surface of the intermediate transfer member or the transfer material is opposed to the photosensitive drum 10 with the intermediate transfer belt 14a interposed therebetween. The corona discharger is provided, and forms a transfer area (no reference numeral) between the intermediate transfer belt 14a and the photosensitive drum 10. A DC voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied to the primary transfer device 14b, and the toner image on the photosensitive drum 10 is transferred onto the intermediate transfer belt 14a or the recording paper P as a transfer material. Transfer to the surface. As the primary transfer device 14b, a transfer roller or a transfer blade can be used in addition to the corona discharge device.

A secondary transfer device 14g, which is a secondary transfer means for retransferring the toner image on the intermediate transfer member to the back surface of the transfer material, is constituted by a corona discharger, and is provided between the primary transfer device 14b and the driving roller 14d. And is provided so as to face the secondary transfer facing roller 14j that is grounded across the intermediate transfer belt 14a,
Polarity opposite to toner (positive polarity in this embodiment)
Is applied to transfer the toner image on the intermediate transfer belt 14a to the back surface of the recording paper P.

The paper charger 150, which is a transfer material charging means, is preferably constituted by a corona discharger, provided opposite the driven roller 14e, which is grounded across the intermediate transfer belt 14a, and has the same polarity as the toner (this embodiment). (In the embodiment, a negative polarity) is applied, and the recording paper P is charged and attracted to the intermediate transfer belt 14a. As the paper charger 150, in addition to the corona discharger, a paper charging brush or a paper charging roller capable of abutting and releasing the saw-toothed electrode and the intermediate transfer belt 14a may be used.

The transfer material charge eliminator 14h serving as the transfer material charge removal means.
Is a driving roller which is preferably constituted by a corona discharger, and which is grounded with the intermediate transfer belt 14a interposed therebetween near a position where the recording paper P is separated from the intermediate transfer belt 14a at an end of the intermediate transfer belt 14a on the fixing device 570 side. An AC voltage superimposed with a DC voltage for preventing separation discharge at the time of separation of the surface toner image having a high charge amount (Q / M) charged by the secondary transfer device 14g and applied to the secondary transfer device 14g; The recording paper P conveyed by the intermediate transfer belt 14a is discharged and separated from the intermediate transfer belt 14a.

The transport section 160 has a separation claw 210 as a transfer material separation assisting means and a spur 162 as a spur member.
The intermediate transfer belt 14a is provided between the curvature section KT at the end of the fixing device 570 side and the fixing device 570 of the fifth example. The conveying section 160 is heated by the heat from the fixing device 570,
If the intermediate transfer belt 14a is deformed or the intermediate transfer belt 1
This prevents the toner image carried on the transfer belt 4a from becoming slightly fused and difficult to transfer, and prevents the toner from being fixed on the intermediate transfer belt 14a.

The separation claw 210, which is a transfer material separation assisting means, is close to the curvature portion KT of the intermediate transfer belt 14a and has a predetermined distance from the intermediate transfer belt 14a, preferably 0.1 to 2.0.
When the recording paper P is separated from the intermediate transfer belt 14a, the recording paper P is bent toward the intermediate transfer belt 14a to be conveyed when the recording paper P is separated from the intermediate transfer belt 14a. To assist the curvature separation of the recording paper P.

[0220] The spur 162, which is a spur member, has a plurality of projections 162a on its peripheral surface, and is provided rotatably about a rotation support shaft 165. The spur 162 guides the back side of the recording sheet P to convey the recording sheet P, prevents the back side toner image of the recording sheet P having the toner image on both sides from being disturbed, and transfers the recording sheet P to the fixing device 570. The recording paper P is stably conveyed to the fixing device 570 while keeping the entering direction constant.

The separation claw 210 and the spur 162 are disposed on the side opposite to the photosensitive drum 10 with respect to the transfer material conveying surface on the intermediate transfer belt 14a or its extension surface.
It is also possible to provide spurs 162 as spur members on both sides of the transfer material conveying surface or an extension surface thereof.

The fixing device 570 of the fifth example has a thin elastic fixing roller 47a as a fixing roller member made of a thin thin cylindrical elastic body for fixing a toner image of an upper surface (front surface). And a lower roll-shaped heat ray fixing roller 17a as a lower heat ray fixing rotating member for fixing a toner image of a lower side (rear side image), and a fixing drive motor (not shown). The heat ray fixing roller 17a is driven and rotated, and the thin plate elastic fixing roller 47a is driven and rotated. A halogen lamp 171g or a xenon lamp (not shown) that emits a heat ray such as an infrared ray or a far-infrared ray including visible light depending on the light source is disposed as a heat ray irradiating means in the center of the thin plate elastic fixing roller 47a and the heat ray fixing roller 17a. Is established. The recording paper P is sandwiched by a nip N formed between the thin plate elastic fixing roller 47a and the heat ray fixing roller 17a, and the toner image on the recording paper P is fixed by applying heat and pressure.

Next, the image forming process will be described.

At the start of image recording, the photosensitive drum 10 is rotated clockwise as shown by the arrow in FIG. The application of the potential is started.

After the photosensitive drum 10 is applied with an electric potential, the laser exposure optical system 120 starts image writing by an electric signal corresponding to the image data, and the surface of the photosensitive drum 10 corresponds to the original image. An electrostatic latent image is formed.

The electrostatic latent image is reversely developed by the developing device 13 in a non-contact state, and a toner image is formed on the photosensitive drum 10 (toner image forming means).

The toner image to be the back side image formed on the photosensitive drum 10 as the image carrier by the above-described image forming process is transferred to the intermediate transfer body by the primary transfer unit 14b in the transfer area (no reference numeral). A certain intermediate transfer belt 14
(a) of FIG. 2 (FIG. 2 (A)).

After the toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is removed by the photosensitive drum AC static eliminator 16, the toner is transferred to the cleaning device 19 which is an image carrier cleaning means, or the photosensitive drum 10 is removed. The toner is cleaned by a cleaning blade 19a made of a rubber material in contact with the toner, and collected by a screw 19b in a not-shown waste toner container.

After the toner image serving as the back image is formed on the intermediate transfer belt 14a as described above, the toner image serving as the front image is continuously formed on the photosensitive drum 10 in the same manner as the image forming process described above. Is formed (see FIG. 2).
(B)). At this time, the image data is changed so that the front surface image formed on the photosensitive drum 10 is a mirror image of the rear surface image formed on the photosensitive drum 10.

With the formation of a surface image on the photosensitive drum 10, recording paper P as a transfer material is sent out by a feed roller 15a from a paper feed cassette 15 as a transfer material storage means, and is used as a transfer material feeding means. Timing roller 1
The toner image of the front surface image formed on the photosensitive drum 10 and the toner image of the back surface image carried on the intermediate transfer belt 14a are transferred in synchronization by the driving of the timing roller 15b. Area (unsigned). At this time, the fed recording paper P is transferred to a paper charger 15 serving as a transfer material charging unit provided on the front side of the recording paper P.
0, the intermediate transfer belt 1 is charged to the same polarity as the toner.
4a, and is conveyed to the transfer area (no symbol). By charging the paper with the same polarity as the toner, the toner image is prevented from being attracted to the toner image on the intermediate transfer belt 14a and the toner image on the photosensitive drum 10, thereby preventing the toner image from being disturbed.

In the transfer area (no sign), the surface image on the photosensitive drum 10 is transferred onto the surface of the recording paper P by the primary transfer device 14b to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied. Transcribed. At this time, the back surface image on the intermediate transfer belt 14a is not transferred to the recording paper P but exists on the intermediate transfer belt 14a.

The recording paper P on which the toner image has been transferred onto the surface is
Polarity opposite to toner (positive polarity in this embodiment)
Is transferred to the secondary transfer device 14g to which the voltage of
The backside image on the peripheral surface of the intermediate transfer belt 14a is retransferred to the backside of the recording paper P by the next transfer unit 14g (FIG. 2).
(C)).

The recording paper P on which toner images are formed on both sides is
The curvature of the curvature portion KT of the intermediate transfer belt 14a, the charge removal operation by the transfer material charge remover 14h as the transfer material charge removal means provided at the end of the intermediate transfer belt 14a, and the conveyance with a predetermined distance from the intermediate transfer belt 14a The sheet is separated from the intermediate transfer belt 14 a by the separation claw 210 provided in the section 160, is conveyed to the fixing device 570 through the spur 162 provided in the conveyance section 160, and is fixed to the thin plate elastic fixing roller 47.
The toner image on the recording paper P is fixed by being conveyed between the nip portion N between the a and the heat ray fixing roller 17a and receiving heat and pressure at the nip portion N. The recording paper P on which double-sided image recording has been performed is sent upside down, and is discharged by a discharge roller 18 to a tray outside the apparatus.

The toner remaining on the peripheral surface of the intermediate transfer belt 14a after the transfer is provided to face the driven roller 14e with the intermediate transfer belt 14a interposed therebetween, and is applied to the intermediate transfer belt 14a with the support shaft 142 as a rotation fulcrum. The intermediate transfer member is cleaned by an intermediate transfer member cleaning device 140 which is an intermediate transfer member cleaning unit having an intermediate transfer member cleaning blade 141 capable of contacting and releasing contact.

The toner remaining on the peripheral surface of the photoreceptor drum 10 after the transfer is subjected to static elimination by the photoreceptor drum AC static eliminator 16 and then cleaned by the cleaning device 19 to be used in the next image forming cycle. Yes.

According to FIG. 17, the fixing device 57 of the fifth example is shown.
Reference numeral 0 denotes a thin plate elastic fixing roller 47a made of a thin cylindrical elastic body as a fixing roller member for fixing the toner image of the upper surface (front side) image, and the toner of the lower (back side) rear image. A thin roller elastic fixing roller 47a made of a thin cylindrical elastic body and an elastic soft roller composed of a lower roll-shaped heat ray fixing roller 17a as a rotatable heat ray fixing rotating member for fixing an image and an elastic soft roller With a wide nip portion N having a width of 30 mm or less, preferably 10 mm or more formed between the heat ray fixing roller 17a as above, the recording paper P entering the nip portion N and passing through the nip portion N is pinched, The toner image on the recording paper P is fixed by applying heat and pressure. As will be described in detail later, both ends of the thin plate elastic fixing roller 47a are held by ring-shaped resin bearings 471j.

As shown in FIG. 18, the thin plate elastic fixing roller 47a as a thin plate fixing roller member for fixing the toner image of the front surface image is formed by a thin plate elastic roller 471a as a thin cylindrical elastic body having spring properties. A roller having a layered elasticity formed by a rubber layer 471b on the outer side (outer peripheral surface) of the thin plate elastic roller 471a. Thin plate elastic roller 4
The rubber layer 471b provided outside (outer peripheral surface) of the rubber layer 71a preferably has a thickness of about 0.5 to 3 mm.
The provision of 71b reduces the occurrence of uneven fixing.

The thin plate elastic roller 471a has a thickness (thickness).
A spring-like metal member having a fatigue limit that can be used as a spring material and is formed of a spring-like metal member using, for example, stainless steel, phosphor bronze, or the like having t2 (mm) of about 0.15 to 0.8 mm. By doing so, when the thin plate elastic roller 471a is applied to the fixing device 570 (or a fixing device 670 described later in the sixth embodiment), fatigue failure due to elastic deformation of the thin plate elastic roller 471a as a cylindrical elastic body is prevented. The occurrence can be prevented. In order to prevent the occurrence of fatigue fracture due to elastic deformation, it was experimentally confirmed that the fatigue limit of the metal member is preferably 14 kP / mm ² or more.

When the outer diameter of the thin elastic roller 471a is φ2 (mm) with respect to the thickness t2 (mm) of the thin elastic roller 471a, φ2 / 70>t2> φ2 / 300 is satisfied. However, the thin plate elastic roller 471a is
0 (or a fixing device 670 to be described later in the sixth embodiment), whereby the thin elastic roller 471a is not deformed or damaged, and the nip portion N has a wide width (nip width) of 10 to 30 mm. It is possible to do. When t2 ≧ φ2 / 70, the thin plate elastic roller 471a
The fixing device 570 (or the sixth embodiment) is too thick.
When applied to a fixing device 670 to be described later, the nip portion N is not deformed into an elliptical shape, and the width of the nip portion N is not increased. t2 ≦ φ
In the case of 2/300, the thickness of the thin plate elastic roller 471a is too thin, and when applied to the fixing device 570 (or a fixing device 670 described later in the sixth embodiment), the strength is too low and the pressing force is insufficient, and the fixing is performed. It becomes uneven.

As shown in FIG. 19, both ends of a thin plate elastic fixing roller 47a which is a fixing roller member using a thin plate elastic roller 471a which is a thin cylindrical elastic body having a spring property are attached to both ends. Resin bearing 47 as a ring-shaped bearing member using a resin member having heat insulation properties
1j, and both ends of the thin plate elastic fixing roller 47a are held by a resin bearing 471j as a bearing member having an inner diameter larger than the outer diameter of the thin plate elastic fixing roller 47a. A thin plate elastic fixing roller 47a integrated with the resin bearings 471j at both ends is rotatable by a bearing B5 fitted into the resin bearing 471j as a bearing member. At this time, the thin plate elastic fixing roller 47a is directly
Can also be held. Further, a shaft portion 17 of the heat ray fixing roller 17a is attached to the lower heat ray fixing roller 17a.
A gear G12 is fixedly provided at one end of 1f, a gear G22 driven and rotated by the fixing drive motor M1 is connected to the gear G12, and the heat ray fixing roller 17a is rotated by the driving of the fixing drive motor M1. , Heat ray fixing roller 1
The thin plate elastic fixing roller 47a pressed by 7a is driven and rotated. By the driven rotation, the rotation of the thin plate elastic fixing roller 47a is made uniform, and uneven fixing is prevented. FIG.
It is preferable that the rubber layer 471b of the above-mentioned thin plate elastic fixing roller 47a, which is indicated by oblique lines in FIG. 9, is provided inside the resin bearings 471j at both ends, so that when the thin plate elastic fixing roller 47a is rotated, Is prevented from being scraped by the resin bearing 471j.

As shown in FIG. 17, a temperature sensor TS3 which is a temperature detecting means using, for example, a contact type thermistor for controlling the temperature is attached to the upper thin plate elastic fixing roller 47a. As the temperature sensor TS3, in addition to the contact type, a non-contact type can be used.

The heat ray fixing roller 17a as a heat ray fixing rotating member for fixing the toner image on the back surface has a cylindrical light transmitting base 171a and a light transmitting outside (outer peripheral surface) of the light transmitting base 171a. Elastic layer 171d and heat ray absorbing layer 171
b and a release layer 171c are provided as a soft roller in that order. A halogen lamp 171g, which is a heat ray irradiating means for emitting heat rays such as infrared rays or far infrared rays including visible light depending on a light source, is provided in the center of the inside of the light transmitting substrate 171a.
And a xenon lamp (not shown). The heat ray fixing roller 17a as a heat ray fixing rotating member is configured as a highly elastic soft roller as described later. A heat ray emitted from the halogen lamp 171g or a xenon lamp (not shown) is absorbed by the heat ray absorbing layer 171b to form a roll-shaped heat ray fixing rotating member capable of rapid heating. It is preferable that a heat equalizing roller TR4 be provided on the surface of the heat ray fixing roller 17a. The heat generation temperature distribution on the peripheral surface of the heat ray fixing roller 17a heated by the heat ray absorption layer 171b is made uniform. Heat uniformizing roller TR
4, uniformity of the temperature unevenness in the vertical and horizontal directions of the heat ray fixing roller 17a caused by the passage of the transfer material is made uniform. TS1 is a temperature sensor attached to the lower heat ray fixing roller 17a, which is a temperature sensor using a contact type thermistor for performing temperature control. As the temperature sensor TS1, a non-contact type sensor can be used in addition to a contact type sensor.

The temperature control of the upper thin plate elastic fixing roller 47a and the lower heat ray fixing roller 17a detects the temperature of the thin elastic plate fixing roller 47a as the upper fixing roller member in the same manner as described above with reference to FIG. A temperature sensor as a temperature detecting means for detecting the temperature (T3 (° C.)) of the thin plate elastic fixing roller 47a by the temperature sensor TS3 as the temperature detecting means and the temperature of the heat ray fixing roller 17a as the lower heat ray fixing rotating member. Heat ray fixing roller 17a by TS1
Temperature (T1 (° C.)) and a storage unit (RO
M, RAM), the temperature (detected temperature) T3 and the temperature (detected temperature) T
Thin plate elastic fixing roller 4 from reference table corresponding to 1
7a and a halogen lamp 171g or a xenon lamp (not shown) for heating the heat ray fixing roller 17a.
The n-off time is referred to through the fixing control unit, and the temperature control of the upper thin plate elastic fixing roller 47a and the lower heat ray fixing roller 17a is performed. In particular, in both-side fixing, since the temperatures of both the upper thin plate elastic fixing roller 47a and the lower heat ray fixing roller 17a affect the fixing, the upper thin plate elastic fixing roller 47a and the lower heat ray fixing roller 1a are affected.
7a requires both temperature control.

A flat nip N is formed between the upper elastic roller and the lower elastic roller to fix the toner image.

The fixing roller member is a thin thin elastic roller 471a having a spring property.
7a is received by the elastic force of the thin plate elastic roller 471a of the thin plate elastic fixing roller 47a. As a result, the thin elastic roller 471a expands in an elliptical shape without plastic deformation, and presses the soft translucent elastic layer 171d of the heat ray fixing roller 17a on the surface of the thin elastic roller 471a which is almost flat, thereby forming a wide flat nip. A portion N is formed. Good fixing of the toner image is performed by the wide nip portion N.

The heat generated by the thin elastic roller 471a as a cylindrical elastic body by the heat rays of the upper halogen lamp 171g and the xenon lamp (not shown), and the absorption of heat rays by the heat rays of the lower halogen lamp 171g and the xenon lamp (not shown). Due to both the heat generated in the layer 171b and the heat generated in the layer 171b, instantaneous heating is difficult due to the heating of the lower heat ray fixing roller 17a during both sides, but quick start (rapid heating) with a short warm-up time is possible with energy saving. A fixing device becomes possible.

As described above with reference to FIG. 5, the configuration of the heat ray fixing roller 17a is such that the cylindrical light transmitting substrate 171a has a thickness of 1 to 20 m, as shown in cross section in FIG.
m, preferably 2-5 mm thick, halogen lamp 171
g or a ceramic material such as sapphire (Al ₂ O ₃ ) or CaF ₂ that transmits heat rays such as infrared rays or far infrared rays from a xenon lamp (not shown) (heat conductivity is (5 to 20) × 10 ⁻ ). ³ J / cm · s · K, specific heat (0.5-2.0) × J / g · K, specific gravity 1.5–3.
0) is mainly used, and a translucent resin using polyimide, polyamide or the like (having a thermal conductivity of (2-4) × 10 ⁻³ J
/ Cm · s · K, specific heat ((1-2) × J / g · K, specific gravity 0.8-1.2), etc. can also be used. For example, as the translucent substrate 171a of the heat ray fixing roller 17a,
When the Pyrex glass (inner diameter 32 mm, outer diameter 40 mm, layer thickness (thickness) 4 mm) (specific heat 0.78 J / g · K, specific gravity 2.32) is used, A-
Heat capacity Q1 per 3 size width (297mm) is about 6
0 cal / deg. Since the wavelength of the heat ray passing through the light-transmitting substrate 171a is 0.1 to 20 μm, and preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler. 1 / wavelength of
2, preferably 1/5 or less, having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles (transmission of infrared rays or far infrared rays including visible light depending on the light source) The transparent substrate 171a may be formed by dispersing fine particles of metal oxide such as ITO, titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. As described above, the translucent substrate 171a does not have good thermal conductivity.

The light-transmitting elastic layer 171d has a thickness of 0.5 to 2 mm.
It is formed of a rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light or infrared rays depending on the light source) using, for example, silicon rubber or fluorine rubber having a thickness of 0 mm, preferably 1 to 5 mm. . Translucent elastic layer 171d
In order to respond to high speed, a method of improving thermal conductivity by mixing a metal oxide powder such as silica, alumina or magnesium oxide as a filler into a base layer (silicone rubber or fluorine rubber) has been adopted. Conductivity (1-3)
× 10 ⁻³ J / cm · s · K, specific heat of (1-2) × J / g
-Use a rubber layer having a K and a specific gravity of 0.9 to 1.0. For example, as the translucent elastic layer 171d of the heat ray fixing roller 17a,
A-3 size width of the light-transmitting elastic layer 171d when silicon rubber having an outer diameter of 50 mm and a layer thickness (thickness) of 5 mm (specific heat is 1.1 J / g · K, specific gravity is 0.91) is used ( 297
The heat capacity Q2 per mm) is about 50 cal / deg. The rubber layer is made of a light-transmitting substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J / cm · s ·
Since it is an order of magnitude lower than K), it functions as a layer having heat insulating properties.
When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a hardness of 40 Hs usually has a hardness of 60 Hs (JIS,
A rubber hardness). Preferred rubber hardness is 5 to 60 Hs. Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is coated with a fluorine-based rubber having a thickness of 20 to 300 μm as an oil-resistant layer to prevent oil swelling. As the silicon rubber of the top layer of the translucent elastic layer 171d, HTV (High Temp) is used.
RTV (RoomTemperature V) which has better releasability than ETERNUS
olcanizing) and LTV (Low Tempe)
(ratio volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, the wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm, and preferably 0.3 to 3 μm. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less including primary and secondary particles,
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
71d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 1 as a heat ray fixing rotating member is provided.
7a is configured as a highly elastic soft roller.

As the heat ray absorbing layer 171b, the remaining heat rays emitted from a halogen lamp 171g or a xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d are used as the light transmitting base 171b. 90 to 100%, preferably 95 to 100% of the heat rays, which are about 100% of the heat rays transmitted through the 171a and the translucent elastic layer 171d, are absorbed by the heat ray absorbing layer 171b to form a heat ray fixing rotating member capable of instantaneous heating. As described above, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F
e ₂ O ₃ ) or the like, and a heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm is sprayed on the outer side (outer peripheral surface) of the light transmitting elastic layer 171 d. It is formed by coating or the like. Heat ray absorbing layer 171
b has a thermal conductivity of the rubber layer of the translucent elastic layer 171d (having a thermal conductivity of (1-3) × 10 ⁻³ J / cm · s · K and a specific heat of (1-2) × J / g · K, specific gravity is 0.9 to 1.0), and a slightly higher (3 to 10) × 10 ⁻³ J / cm · s · K (specific heat is increased by adding an absorbent such as carbon black). 2.0) × J / g · K, and the specific gravity can be set to (〜0.9). As the heat ray absorbing layer 171b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%,
For example, if it is about 20 to 80%, the heat rays leak, and when the heat ray fixing roller 17a as a heat ray fixing rotating member is used for monochrome image formation due to the leaked heat rays, a specific position of the heat ray fixing roller 17a is determined by filming or the like. When the black toner adheres to the surface of the device, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of the heat rays is further superimposed on the portion to damage the heat ray absorbing layer 171b. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The heat rays transmitted through the heat ray absorbing layer 171
The heat ray absorption rate of the heat ray absorption layer 171b is set to 90 to 100%, which is about 100%, and preferably 95 to 100% so that the heat ray is completely absorbed by b. When the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate due to the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b may be damaged by local heating by the thin film and the strength may be insufficient. If the thickness of the heat ray absorbing layer 171b exceeds 500 μm and is too thick, poor heat conduction or large heat capacity makes rapid heating difficult. By setting the heat ray absorption rate of the heat ray absorption layer 171b to 90 to 100%, which is about 100%, preferably 95 to 100%, or setting the thickness of the heat ray absorption layer 171b to 10 to 500 μm, preferably 20 to 100 μm, Local heat generation in the absorption layer 171b is prevented, and uniform heat generation is performed. Heat ray absorbing layer 1
Since the wavelength of the heat ray projected on 71b is 0.1 to 20 μm, and preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler. / 2, preferably 1/5 or less, including primary and secondary particles, having an average particle size of 1 μm or less, preferably 0.1 μm
Fine particles of metal oxides such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, calcium carbonate, etc. having the following heat ray transmittance (infrared ray or visible ray including visible light depending on the light source) are used as the resin binder. The heat ray absorbing layer 171b may be formed by dispersing 5 to 50% by weight. Thus, the heat ray absorbing layer 171b
Since the heat capacity is reduced so that the temperature rises immediately, the heat ray fixing roller 17a as a heat ray fixing rotating member is used.
This prevents the problem that the temperature is lowered and the fixing unevenness occurs. As the heat ray absorbing layer 171b, carbon black, graphite,
A mixture of iron black (Fe ₃ O ₄ ), various ferrites and their compounds, and powders such as copper oxide, cobalt oxide, and red iron oxide (Fe ₂ O ₃ ) may be used. For example, heat ray fixing roller 1
7a of the heat ray absorbing layer 171b (or the dual-purpose layer 17 described later).
As 1Z), a fluororesin (specific heat: 2.0 J / g · K, specific gravity: 0.9) having a layer thickness (thickness) of 50 μm is applied to the surface (outer peripheral surface) of the light-transmitting elastic layer 171 d having an outer diameter of 50 mm. A of heat ray absorbing layer 171b (or dual-purpose layer 171Z) when used
The heat capacity Q3 per −3 size width (297 mm) is about 1.0 cal / deg. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

Further, a PFA (fluororesin) tube having a thickness of 30 to 100 μm is coated on the outside (outer peripheral surface) of the heat ray absorbing layer 171b separately from the heat ray absorbing layer 171b to improve the releasability from the toner. Or fluororesin (PF
A or PTFE) Release layer 171c coated with a paint of 20 to 30 μm (having a thermal conductivity of (1 to 10) × 10 ⁻³ J / cm.
S · K, specific heat (（2.0) × J / g · K, specific gravity (〜0.9)) (separated type).

Further, as shown in the cross section in FIG. 5B, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (Fe ₂ O ₃ ), etc. Heat-absorbing member mixed with powder of PTFE, and a fluororesin (PFA or PT) that also serves as a binder and a release agent
FE) paint is mixed and mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG.
A heat-fixing rotary member in the form of a roll having elasticity may be formed outside (outer peripheral surface) of the translucent elastic layer 171d formed outside (outer peripheral surface). The thermal conductivity of the dual-purpose layer 171Z is substantially the same as the thermal conductivity of the heat ray absorbing layer 171b.
(3-10) × 10 ⁻³ J / cm · s · K (specific heat
2.0) × J / g · K, and specific gravity is (０．９0.9).
As described above, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the translucent base 171a and the translucent elastic layer 171d are:
In order to completely absorb the heat rays transmitted through the light-transmitting base 171a and the light-transmitting elastic layer 171d, the heat ray absorptivity of the dual-purpose layer 171Z is set to 90 to 100%, which is about 100%, and preferably 95 to 100%. When the heat ray absorptivity in the dual-purpose layer 171Z is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the heat ray fixing rotating member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the heat ray fixing rotating member at a specific position due to, for example, mining, heat is generated from the adhering portion by the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the dual-purpose layer 171Z. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The combined layer 171Z has a heat ray absorptivity of about 100%, which is about 90-100%, preferably 95-1%, so that the heat rays transmitted through the heat ray fixing rotary member are completely absorbed in the heat ray fixing rotating member.
00%. Further, local heat generation in the dual-purpose layer 171Z is also prevented, and uniform heat generation is performed. In addition, the combined use layer 17
Since the wavelength of the heat ray projected on 1Z is 0.1 to 20 μm, preferably 0.3 to 3 μm, an adjuster for hardness and thermal conductivity is added as a filler, but the particle size is 1 to the wavelength of the heat ray. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less, preferably 0.1 μm or less including primary and secondary particles (infrared ray or visible ray including visible light depending on the light source). The dual-purpose layer 171Z may be formed by dispersing fine particles of a metal oxide such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder.

In the same manner as described above with reference to FIG. 6, if the concentration distribution of the above-described heat ray absorbing member is uniformly provided on the heat ray absorbing layer 171b of the heat ray fixing roller 17a as a roll-shaped rotating member for fixing the heat ray, Heat is concentrated in the absorption layer 171b, and the heat easily flows to the side of the light-transmitting elastic layer 171d. It is preferable to generate heat inside from the viewpoint of dispersing the heat generation distribution. As shown in the graph (a), the concentration distribution of the heat ray absorbing layer 171b is set such that the interface on the side of the light-transmitting elastic layer 171d adjacent thereto has a low concentration, is gradually inclined toward the outer peripheral surface side, and is gradually increased. (Thickness t of heat ray absorbing layer 171b)
1/3 from the light-transmitting elastic layer 171d side.
(Position of about degree) so as to obtain a concentration that absorbs 100% so as to be saturated. Thereby, the heat ray absorbing layer 171b
As shown in the graph (b), the heat generation distribution due to the absorption of the heat ray at the point has a maximum value near the center of the heat ray absorption layer 171b and a minimum value near the interface and the outer peripheral surface of the heat ray absorption layer 171b. It is formed in a shape. Alternatively, the heat ray absorbing layer 171b
It is preferable to provide a light-transmissive heat-resistant resin (polyimide, fluororesin or silicon resin) with a thickness of 10 to 500 μm, preferably 20 to 100 μm on the interface or the outer peripheral surface of the substrate. Further, it is preferable to suppress heat loss as a member having a lower thermal conductivity than the translucent substrate 171a. This reduces heat generation due to absorption of heat rays at the interface, prevents heat from flowing out, and prevents damage to the adhesive layer and heat ray absorbing layer 171b at the interface. In addition, before the outer peripheral surface side (the heat ray absorbing layer 171).
2/3 from the light-transmitting base 171a side with respect to the thickness t1 of b.
(About ４ of the position) to saturate the concentration distribution from the outer peripheral surface to the outer peripheral surface. Note that a saturated layer may be formed as shown by a dotted line. In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle.

In the same manner as described above with reference to FIG. 7, the outer diameter φ of the cylindrical light-transmitting substrate 171a of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is set to 15 to 15.
A thickness t of 60 mm is used. A thicker thickness t is better in terms of strength, and a thinner thickness is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the thickness t is outside the cylindrical light-transmitting base 171a. The relationship between the diameter φ and the thickness t is 0.02 ≦ t / φ ≦ 0.20, and preferably 0.04 ≦ t / φ ≦ 0.10. When the outer diameter φ of the transparent substrate 171a is 40 mm, the thickness t of the transparent substrate 171a is 0.8 mm ≦ t ≦ 8 m.
m, preferably 1.6 mm ≦ t ≦ 4.0 mm. When t / φ is less than 0.02 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.20, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, depending on the material, a light-transmitting substrate may absorb about 1 to 20% of heat rays, and it is preferable that the substrate be thin as long as the strength can be maintained.

As described above, the use of the fixing device 570 of the fifth example described with reference to FIG. A wide nip portion N is formed and the toner image is fixed.
1a and the heat generated by the heat rays of the halogen lamp 171g and the xenon lamp (not shown) in the heat ray absorbing layer 171b enable high-speed fixing while saving energy and shortening the warm-up time, and are uniform and stable. A fixing device and an image forming device that can obtain good fixing properties depending on temperature can be obtained. In particular, in the double-sided image forming apparatus described with reference to FIG. 16, it is possible to fix the surface toner image at a high speed in the double-sided image formation while saving energy and shortening the warm-up time, and to obtain a good surface toner image by a uniform and stable temperature. Can be fixed.

Embodiment 6 An image of a sixth embodiment of the fixing device according to the present invention and an image of one embodiment of the image forming apparatus in which the fixing device is applied to the second example of the image forming device described in the second embodiment. FIG. 20 or FIG. 21 and the first embodiment regarding the forming process and each mechanism.
This will be described with reference to FIGS. 4 to 8 described above and FIG. 18 described in the fifth embodiment. FIG. 20 is a sectional view of a color image forming apparatus showing an embodiment of a sixth example of the image forming apparatus according to the present invention, and FIG. 21 is a sectional view of a sixth example of the fixing apparatus according to the present invention. It is a block diagram.

According to FIG. 20, the photosensitive drum 10 serving as an image carrier has a light-transmitting member on the outer periphery of a cylindrical base formed of a light-transmitting member such as glass or light-transmitting acrylic resin. It has a conductive layer and a photoconductor layer of an organic photosensitive layer (OPC).

The photosensitive drum 10 is rotated clockwise as indicated by an arrow in FIG. 20 by power from a driving source (not shown) with the light-transmitting conductive layer grounded.

In the present invention, the exposure beam for image exposure is
The photoconductor layer of the photoconductor drum 10, which is the image forming point, only needs to have an exposure light amount of a wavelength that can provide an appropriate contrast with respect to the light attenuation characteristic (photocarrier generation) of the photoconductor layer. . Therefore, the light transmittance of the light-transmitting substrate of the photosensitive drum 10 in the present embodiment does not need to be 100%, and may have a characteristic of absorbing a certain amount of light when transmitting the exposure beam. Good. The point is that any suitable contrast can be provided. As a material of the light-transmitting substrate, an acrylic resin, particularly one obtained by polymerizing a methyl methacrylate monomer, is preferably used because of its excellent light-transmitting properties, strength, accuracy, surface properties, etc. Various translucent resins such as acryl, fluorine, polyester, polycarbonate, polyethylene terephthalate and the like used for the above can be used. Further, as long as it has a light-transmitting property with respect to the exposure light, it may be colored. As the light-transmitting conductive layer, indium tin oxide (I
TO), tin oxide, lead oxide, indium oxide, copper iodide, or a metal thin film of Au, Ag, Ni, Al, or the like that maintains light transmissivity. Reactive deposition method, various sputtering methods, various CV
D method, dip coating method, spray coating method and the like can be used.
Various organic photosensitive layers (OPC) can be used as the photoconductor layer.

The organic photosensitive layer serving as the photosensitive layer of the photoconductor layer includes a charge generation layer (CGL) mainly composed of a charge generation substance (CGM) and a charge transport layer (CTM) mainly composed of a charge transport substance (CTM). And CTL). An organic photosensitive layer having a two-layer structure has high durability as an organic photosensitive layer due to its thick CTL and is suitable for the present invention.
The organic photosensitive layer may have a single layer structure containing a charge generation material (CGM) and a charge transport material (CTM) in one layer. ,
Usually, a binder resin is contained.

A scorotron charger 11 as a charging unit described below, and an exposure optical system 1 as an image writing unit will be described.
2. The developing device 13 as a developing unit is prepared for an image forming process for each color of yellow (Y), magenta (M), cyan (C) and black (K), respectively. Are arranged in the order of Y, M, C, and K with respect to the rotation direction of the photosensitive drum 10 indicated by the arrow in FIG.

Scorotron charger 11 as charging means
Is mounted so as to face and be close to the photosensitive drum 10 in a direction (perpendicular to the plane of FIG. 20) orthogonal to the moving direction of the photosensitive drum 10 as an image forming body. A control grid (unsigned) maintained at a predetermined potential with respect to the layer;
As a, for example, a sawtooth electrode is used, and a charging action (in this embodiment, negative charging) is performed by corona discharge having the same polarity as that of the toner, thereby giving a uniform potential to the photosensitive drum 10. As the corona discharge electrode 11a, a wire electrode or a needle electrode may be used.

The exposure optical system 12 for each color is a linear exposure element (LED) in which a plurality of LEDs (light emitting diodes) as light emitting elements for image exposure light are arranged in an array parallel to the axis of the photosensitive drum 10. (Not shown) and a selfoc lens (not shown) as an equal-magnification imaging element are configured as an exposure unit attached to a holder. Cylindrical holding member 2
At 0, the exposure optical system 12 for each color is attached and housed inside the base of the photosensitive drum 10. In addition, as the exposure element, a linear element in which a plurality of light emitting elements such as FL (phosphor emission), EL (electroluminescence), and PL (plasma discharge) are arranged in an array is used.

The exposure optical system 12 as an image writing means for each color moves the exposure position on the photosensitive drum 10 between the scorotron charger 11 and the developing device 13 to the developing device 13. It is arranged inside the photoconductor drum 10 in a state provided on the upstream side in the rotation direction of the drum 10.

The exposure optical system 12 performs image processing based on image data of each color sent from a separate computer (not shown) and stored in the memory, and then performs image processing on the uniformly charged photosensitive drum 10. Exposure is performed to form a latent image on the photosensitive drum 10. The emission wavelength of the light-emitting element used in this embodiment is usually 6 for the toners of Y, M, and C, which have high translucency.
The wavelength in the range of 80 to 900 nm is good, but the wavelength may be shorter than this, since the color toner does not have sufficient translucency since image exposure is performed from the back surface.

The developing device 13 as a developing means for each color includes:
Inside yellow (Y), magenta (M), cyan (C)
Alternatively, it contains a black (K) two-component (or one-component) developer and is formed of, for example, a cylindrical nonmagnetic stainless steel or aluminum material having a thickness of 0.5 to 1 mm and an outer diameter of 15 to 25 mm, respectively. Developing sleeve 13a.

In the developing region, the developing sleeve 13a is kept in non-contact with the photosensitive drum 10 by a contact roller (not shown) with a predetermined gap, for example, 100 to 1000 μm, and the developing sleeve 13a is rotated in the rotational direction of the photosensitive drum 10. At the closest position, the developing sleeve 13a rotates in the forward direction. During development, a DC voltage of the same polarity as the toner (minus polarity in the present embodiment) or a DC voltage superimposed on the DC voltage is applied to the developing sleeve 13a. By applying a bias voltage, non-contact reversal development is performed on the exposed portion of the photoconductor drum 10. At this time, the precision of the development interval needs to be about 20 μm or less in order to prevent image unevenness.

As described above, the developing unit 13 transfers the electrostatic latent image formed on the photosensitive drum 10 by the charging by the scorotron charger 11 and the image exposure by the exposure optical system 12 in a non-contact state. Reversal development is performed with toner having the same polarity as the charge polarity of No. 10 (in the present embodiment, the photosensitive drum is negatively charged, and the toner has a negative polarity).

When the image carrier driving motor (not shown) is started by the start of image formation, the photosensitive drum 10 is moved to the position shown in FIG.
, And at the same time, application of a potential to the photosensitive drum 10 is started by the charging action of the Y scorotron charger 11. After a potential is applied to the photosensitive drum 10, image writing is started by the first color signal, that is, an electric signal corresponding to the Y image data in the Y exposure optical system 12, and the rotation of the photosensitive drum 10 causes the image writing to start. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface. This latent image is a Y developing device 1
3 and the photosensitive drum 1
A yellow (Y) toner image is formed on 0.

Next, the photosensitive drum 10 places an M scorotron charger 11 on the yellow (Y) toner image.
A potential is applied by the charging action of the M exposure optical system 12
Of the yellow (Y) toner image by the non-contact reversal development by the M developing device 13 is performed. A magenta (M) toner image is formed on the image.

By the same process, the cyan (C) toner image corresponding to the third color signal is further processed by the C scorotron charger 11, the exposure optical system 12, and the developing device 13, and the K scorotron charger 11 , Exposure optical system 1
A black (K) toner image corresponding to the fourth color signal is sequentially superimposed and formed by the second and developing units 13, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10. You.

As described above, in this embodiment, Y, M,
The exposure of the organic photosensitive layer of the photoconductor drum 10 by the C and K exposure optical systems 12 is performed through a transparent substrate from the inside of the photoconductor drum 10. Therefore, the exposure (image writing) of the image corresponding to the second, third and fourth color signals can form an electrostatic latent image without being shielded by the previously formed toner image. Exposure may be performed from the outside of the photoreceptor drum 10, although it is preferable.

On the other hand, the recording paper P as a transfer material is sent out from a paper feed cassette 15 as a transfer material storage means by a half-moon-shaped feed roller (no code), and is fed by a feed roller (no code). Timing roller 15b
Transported to

The recording paper P is synchronized with the color toner image carried on the photosensitive drum 10 by the driving of the timing roller 15b, and is charged by the paper charger 150 as the transfer material charging means, so that the transport belt 14A is charged. And is fed to the transfer area. The recording paper P, which has been closely transported by the transport belt 14A, is rotated around the photosensitive drum 10 by a transfer unit 14c as a transfer unit to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied in a transfer area. The color toner images on the surface are collectively transferred to the recording paper P.

The recording paper P on which the color toner image has been transferred is
The charge is removed by a transfer material removing unit 14h as a transfer material removing unit, separated from the transport belt 14A, and transported to the fixing device 670 of the sixth example.

The fixing device 670 according to the sixth example includes a heat ray fixing roller 17a serving as an upper roll-shaped heat ray fixing rotating member for fixing a color toner image, and a lower thin plate-like thin cylindrical elastic member. The heat-fixing roller 17a is driven and rotated by a fixing driving motor (not shown), and the thin-plate elastic fixing roller 47a is driven to rotate. Halogen lamps 171g and xenon lamps (not shown) that emit heat rays such as infrared rays or far infrared rays including visible light depending on the light source are disposed as heat ray irradiation means in the center of the heat ray fixing roller 17a and the thin plate elastic fixing roller 47a. Is established.

Heat ray fixing roller 17a and heat fixing film 4
7A, the recording paper P is nipped by a nip N, and the color toner image on the recording paper P is fixed by applying heat and pressure. Is discharged to the tray at the top of the device.

The toner remaining on the peripheral surface of the photosensitive drum 10 after the transfer is transferred to a cleaning blade 19 provided in a cleaning device 19 as an image forming body cleaning means.
Cleaning is performed by a. The photosensitive drum 10 from which the residual toner has been removed is uniformly charged by the scorotron charger 11, and enters the next image forming cycle.

As shown in FIG. 21, the fixing device 670 of the sixth example is configured such that the upper and lower rollers of the fixing device 570 described in the fifth embodiment are upside down, and is used for fixing a color toner image. And a thin sheet-like elastic fixing roller 47a as a fixing roller member made of a thin sheet-like thin cylindrical elastic body on the lower side. A wide nip portion N having a width of 30 mm or less, preferably 10 mm or more, formed between the hot-wire fixing roller 17a as a soft roller and the thin elastic elastic roller 47a made of a thin cylindrical elastic body and having elasticity. Nip part N
The recording paper P that has entered the nip portion N and enters the nip is pinched, and the toner image on the recording paper P is fixed by applying heat and pressure. With a configuration similar to that described above with reference to FIG. 19 of the fifth embodiment, both ends of the thin plate elastic fixing roller 47a are held by a ring-shaped resin bearing 471j, and a fixing drive motor (not shown in FIG. 19) is used. (See motor M1)
As a result, the heat ray fixing roller 17a is driven and rotated, and the thin plate elastic fixing roller 47a is driven to rotate (see FIG. 19).

A heat ray fixing roller 17a as a heat ray fixing rotating member for fixing a toner image on a transfer material has a cylindrical light transmitting substrate 171a and an outer surface (outer peripheral surface) of the light transmitting substrate 171a. Translucent elastic layer 171d and heat ray absorbing layer 17
1b and a release layer 171c are provided in that order as a soft roller. Halogen lamp 171 which is a heat ray irradiating means for emitting a heat ray such as infrared ray or far infrared ray including visible light depending on a light source is provided in the center of the interior of the transparent substrate 171a.
g or a xenon lamp (not shown). The heat ray fixing roller 17a as a heat ray fixing rotating member is configured as a highly elastic soft roller as described later.
A heat ray emitted from the halogen lamp 171g or a xenon lamp (not shown) is absorbed by the heat ray absorbing layer 171b to form a roll-shaped heat ray fixing rotating member capable of rapid heating. Preferably, a heat uniformizing roller TR4 is provided on the surface of the heat ray fixing roller 17a. The heat uniformizing roller TR4 using a heat roller or a metal roller member having good thermal conductivity such as an aluminum material or a stainless steel material. Heat ray fixing roller 17a heated by heat ray absorbing layer 171b
The heat generation temperature distribution on the peripheral surface is made uniform. Heat uniformizing roller T
By R4, the temperature unevenness in the vertical and horizontal directions of the heat ray fixing roller 17a due to the passage of the transfer material is made uniform.

Reference numeral TS1 denotes a temperature sensor attached to the upper heat ray fixing roller 17a, which is a temperature sensor using a contact type thermistor for controlling the temperature. As the temperature sensor TS1, a non-contact type sensor can be used in addition to a contact type sensor. Further, a temperature sensor TS3, which is a temperature detecting means using a contact-type thermistor, for performing temperature control is attached to the lower thin plate elastic fixing roller 47a. As the temperature sensor TS3, in addition to the contact type, a non-contact type can be used.

The thin elastic fixing roller 47a as the lower thin fixing roller member is composed of a thin elastic roller 471a as a thin cylindrical elastic body having a spring property, as described above with reference to FIG. A roller having a layered elasticity formed by a rubber layer 471b on the outer side (outer peripheral surface) of the thin plate elastic roller 471a. The thickness of the rubber layer 471b provided on the outer side (outer peripheral surface) of the thin plate elastic roller 471a is preferably about 0.5 to 3 mm. By providing the rubber layer 471b, the occurrence of uneven fixing is reduced.

The thickness (thickness) of the thin elastic roller 471a is
A spring-like metal member having a fatigue limit that can be used as a spring material and is formed of a spring-like metal member using, for example, stainless steel, phosphor bronze, or the like having t2 (mm) of about 0.15 to 0.8 mm. By doing so, in the case where the thin plate elastic roller 471a is applied to the fixing device 670, the occurrence of fatigue failure due to the elastic deformation of the thin plate elastic roller 471a as a cylindrical elastic body can be prevented. In order to prevent the occurrence of fatigue fracture due to elastic deformation, it was experimentally confirmed that the fatigue limit of the metal member is preferably 14 kP / mm ² or more.

When the outer diameter of the thin plate elastic roller 471a is φ2 (mm) with respect to the thickness t2 (mm) of the thin plate elastic roller 471a, φ2 / 70>t2> φ2 / 300 is satisfied. However, the thin plate elastic roller 471a is
This is preferable in the case where it is applied to 0, whereby the width (nip width) of the nip portion N can be increased to 10 to 30 mm without deformation or breakage of the thin plate elastic roller 471a. When t2 ≧ φ2 / 70, the thin plate elastic roller 471
If the thickness of “a” is too large, when applied to the fixing device 670, it does not deform into an elliptical shape and the width of the nip portion N does not increase. t
When 2 ≦ φ2 / 300, the thickness of the thin plate elastic roller 471a is too thin, and when applied to the fixing device 670, the strength is too low and the pressing force is insufficient, resulting in uneven fixing.

The temperature control of the upper heat ray fixing roller 17a and the lower thin sheet elastic fixing roller 47a is performed by detecting the temperature of the heat ray fixing roller 17a as the upper heat ray fixing rotating member, as described above with reference to FIG. Temperature sensor TS3 as a temperature detecting means for detecting the temperature (T1 (° C.)) of the heat ray fixing roller 17a by the temperature sensor TS1 as the temperature detecting means and the temperature of the thin elastic fixing roller 47a as the lower fixing roller member. Thin plate elastic fixing roller 47
a (T3 (° C.)) and a storage unit (RO)
M, RAM) stored in the ROM as a reference table, the temperature (detected temperature) T1 and the temperature (detected temperature) T
Halogen lamps 171g from the reference table corresponding to No. 3 and for heating the thin plate elastic fixing roller 47a
The on-off time of the xenon lamp (not shown) is referred to through a fixing control unit, and the upper heat ray fixing roller 17
a and the temperature of the lower thin plate elastic fixing roller 47a are controlled. In particular, the heating control is performed from both sides in order to shorten the warm-up time. However, the temperature control of the fixing after the warming-up is performed quickly by controlling the heating from both sides. In particular, in the case of fixing a color toner image, both the temperature of the upper heat ray fixing roller 17a and the temperature of the lower thin plate elastic fixing roller 47a affect glossiness and color, so that both temperature controls are required. .

A flat nip portion N is formed between the upper elastic roller and the lower elastic roller to fix the toner image.

The fixing roller member is a thin thin elastic roller 471a having a spring property.
7a is received by the elastic force of the thin plate elastic roller 471a of the thin plate elastic fixing roller 47a. As a result, the thin elastic roller 471a expands in an elliptical shape without plastic deformation, and presses the soft translucent elastic layer 171d of the heat ray fixing roller 17a on the surface of the thin elastic roller 471a which is almost flat, thereby forming a wide flat nip. A portion N is formed. Good fixing of the toner image is performed by the wide nip portion N.

The heat generated by the heat ray absorbing layer 171b of the heat ray fixing roller 17a and the thin sheet elastic fixing roller 47a by the heat rays of the upper and lower halogen lamps 171g and xenon lamps (not shown) saves energy and has a short warm-up time (quick start). Thus, a fixing device capable of performing the fixing can be realized.

As described above with reference to FIG. 5, the structure of the heat ray fixing roller 17a is, as shown in the cross section in FIG.
m, preferably 2-5 mm thick, halogen lamp 171
g or a ceramic material such as sapphire (Al ₂ O ₃ ) or CaF ₂ which transmits heat rays such as infrared rays or far infrared rays from a xenon lamp (not shown) (heat conductivity is (5-20) × 10 ^{− 3} J / cm · s · K, specific heat (0.5-2.0) × J / g · K, specific gravity 1.5–3.
0) is mainly used, and a translucent resin using polyimide, polyamide or the like (having a thermal conductivity of (2-4) × 10 ⁻³ )
J / cm · s · K, specific heat of (1-2) × J / g · K, specific gravity of 0.8-1.2) and the like can also be used. For example, as the translucent substrate 171a of the heat ray fixing roller 17a, the inner diameter is 32 mm, the outer diameter is 40 mm, and the layer thickness (thickness) is 4 m.
m Pyrex glass (specific heat 0.78 J / g · K,
When the specific gravity is 2.32), the heat capacity Q1 per A-3 size width (297 mm) of the translucent substrate 171a is about 60 cal / deg. In addition, the translucent substrate 171
Since the wavelength of the heat ray passing through a is 0.1 to 20 μm, preferably 0.3 to 3 μm, a modifier for hardness and thermal conductivity is added as a filler, but the particle size is １ ／ of the wavelength of the heat ray. Heat ray transmittance of 1 μm or less, preferably 1 μm or less, preferably 0.1 μm or less, preferably 1/5 or less, including primary and secondary particles. The transparent substrate 171a may be formed by dispersing fine particles of metal oxide such as ITO, titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder. The average particle size including primary and secondary particles in the layer is 1μ.
m or less, preferably 0.1 μm or less is preferable for preventing light scattering and reaching the heat ray absorbing layer 171b. As described above, the translucent substrate 171a does not have good thermal conductivity.

The light-transmitting elastic layer 171d has a thickness of 0.5 to 2 mm.
It is formed of a rubber layer (base layer) that transmits heat rays (infrared rays or visible rays including visible light or infrared rays depending on the light source) using, for example, silicon rubber or fluorine rubber having a thickness of 0 mm, preferably 1 to 5 mm. . Translucent elastic layer 171d
In order to respond to high speed, a method of improving thermal conductivity by mixing a metal oxide powder such as silica, alumina or magnesium oxide as a filler into a base layer (silicone rubber or fluorine rubber) has been adopted. Conductivity (1-3)
× 10 ⁻³ J / cm · s · K, specific heat of (1-2) × J / g
-Use a rubber layer having a K and a specific gravity of 0.9 to 1.0. For example, as the translucent elastic layer 171d of the heat ray fixing roller 17a,
A-3 size width of the light-transmitting elastic layer 171d when silicon rubber having an outer diameter of 50 mm and a layer thickness (thickness) of 5 mm (specific heat is 1.1 J / g · K, specific gravity is 0.91) is used ( 297
The heat capacity Q2 per mm) is about 50 cal / deg. The rubber layer is made of a light-transmitting substrate using a glass member having a thermal conductivity of (5-20) × 10 ⁻³ J / cm · s ·
Since it is an order of magnitude lower than K), it functions as a layer having heat insulating properties.
When the thermal conductivity is increased, the rubber hardness generally tends to increase. For example, a rubber having a hardness of 40 Hs usually has a hardness of 60 Hs (JIS,
A rubber hardness). Preferred rubber hardness is 5 to 60 Hs. Most of the translucent elastic layer 171d of the heat ray fixing rotating member is occupied by the base layer, and the amount of compression during pressurization is determined by the rubber hardness of the base layer. The intermediate layer of the light-transmitting elastic layer 171d is coated with a fluorine-based rubber having a thickness of 20 to 300 μm as an oil-resistant layer to prevent oil swelling. As the silicon rubber of the top layer of the translucent elastic layer 171d, HTV (High Temp) is used.
RTV (RoomTemperature V) which has better releasability than ETERNUS
olcanizing) and LTV (Low Tempe)
(ratio volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, the wavelength of the heat ray passing through the translucent elastic layer 171d is 0.1 to 20 μm, and preferably 0.3 to 3 μm. / 2, preferably 1/5 or less, having an average particle diameter of 1 μm or less including primary and secondary particles,
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission of preferably 0.1 μm or less (in some cases, transmitting infrared or far infrared rays including visible light depending on the light source),
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
71d may be formed. It is preferable that the average particle diameter including the primary and secondary particles in the layer is 1 μm or less, preferably 0.1 μm or less in order to prevent light scattering and reach the heat ray absorbing layer 171b. By providing the translucent elastic layer 171d, the heat ray fixing roller 1 as a heat ray fixing rotating member is provided.
7a is configured as a highly elastic soft roller.

As the heat ray absorbing layer 171b, the remaining heat rays emitted from a halogen lamp 171g or a xenon lamp (not shown) and absorbed by the light transmitting base 171a and the light transmitting elastic layer 171d are used as the heat transmitting layer 171b. 90 to 100%, preferably 95 to 100%, of the heat rays, which are almost 100% of the heat rays transmitted through the 171a and the translucent elastic layer 171d, are absorbed by the heat ray absorbing layer 171b to form a heat ray fixing rotating member capable of instantaneous heating. As described above, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (F
e ₂ O ₃ ) or the like, and a heat ray absorbing member having a thickness of 10 to 500 μm, preferably 20 to 100 μm is sprayed on the outer side (outer peripheral surface) of the light transmitting elastic layer 171 d. It is formed by coating or the like. Heat ray absorbing layer 171
b has a thermal conductivity of the rubber layer of the translucent elastic layer 171d (having a thermal conductivity of (1-3) × 10 ⁻³ J / cm · s · K and a specific heat of (1-2) × J / g · K, specific gravity is 0.9 to 1.0), and a slightly higher (3 to 10) × 10 ⁻³ J / cm · s · K (specific heat is increased by adding an absorbent such as carbon black). 2.0) × J / g · K, and the specific gravity can be set to (〜0.9). As the heat ray absorbing layer 171b, a metal roller member such as a nickel electroformed roller may be provided with a similar thickness. At this time, it is preferable that the inside (the inner peripheral surface) is subjected to black oxidation treatment in order to absorb heat rays. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%,
For example, if it is about 20 to 80%, the heat rays leak, and when the heat ray fixing roller 17a as a heat ray fixing rotating member is used for monochrome image formation due to the leaked heat rays, a specific position of the heat ray fixing roller 17a is determined by filming or the like. When the black toner adheres to the surface of the device, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of the heat rays is further superimposed on the portion to damage the heat ray absorbing layer 171b. In addition, when used for forming a color image, the absorption efficiency of the color toner is generally low, and there is a difference in the absorption efficiency between the color toners, resulting in poor fixing or uneven fixing. Therefore, light is emitted from the halogen lamp 171g or a xenon lamp (not shown), and the light-transmitting base 171a and the light-transmitting elastic layer 171 are emitted.
The remaining heat rays absorbed by the light-transmitting substrate 171a and the light-transmitting elastic layer 171d are the remaining heat rays absorbed by the heat ray absorbing layer 1.
The heat ray absorption rate of the heat ray absorbing layer 171b is set to 90 to 100%, which is substantially 100%, and preferably 95 to 100% so that the heat ray is completely absorbed by 71b. As a result, the color toner, which is difficult to be fixed by heat rays due to different spectral characteristics, is favorably melted. In particular, in the color image formation in FIG. 20, it is difficult to fix by heat rays due to different spectral characteristics. The superimposed color toner image on the transfer material having a thick toner layer is fused well. Further, when the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate due to the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b is damaged by local heating by the thin film and the cause of the insufficient strength. When the thickness of the heat ray absorbing layer 171b exceeds 500 μm and is too thick, poor heat conduction or large heat capacity makes rapid heating difficult. The heat ray absorption rate of the heat ray absorption layer 171b is about 100%, which is 9%.
By setting the thickness of the heat ray absorbing layer 171b to 0 to 100%, preferably 95 to 100%, or setting the thickness of the heat ray absorbing layer 171b to 10 to 500 μm, preferably 20 to 100 μm,
Local heat generation in 1b is prevented, and uniform heat generation is performed. Since the wavelength of the heat ray projected on the heat ray absorbing layer 171b is 0.1 to 20 μm, preferably 0.3 to 3 μm, a hardness or thermal conductivity modifier is added as a filler. 1/2 of the wavelength of the heat ray, preferably 1/5
Titanium oxide having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles, and having a transmittance of infrared rays or infrared rays containing visible light or far infrared rays depending on the light source. The heat ray absorbing layer 171b may be formed by dispersing fine particles of a metal oxide such as aluminum, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate in a resin binder in an amount of 5 to 50% by weight. In this way, the heat capacity of the heat ray absorbing layer 171b is reduced so that the temperature rises immediately. Therefore, the temperature of the heat ray fixing roller 17a as a heat ray fixing rotating member is lowered, and the fixing unevenness occurs. To prevent. Heat ray absorbing layer 171b
As for silicone rubber or fluoro rubber with elasticity,
Carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and compounds thereof, and a mixture of powders such as copper oxide, cobalt oxide, and red iron oxide (Fe ₂ O ₃ ) may be used. For example, the heat ray absorbing layer 171b of the heat ray fixing roller 17a
(Or a combined layer 171Z described later) with an outer diameter of 50 m.
m on a surface (outer peripheral surface) of the light-transmitting elastic layer 171d, a fluororesin having a layer thickness (thickness) of 50 μm (specific heat 2.0 J / g ·
K, specific gravity 0.9) when the heat ray absorbing layer 171b is used.
A-3 size width (297 m) of (or combined layer 171Z)
The heat capacity Q3 per m) is about 1.0 cal / deg. As the heat ray absorbing layer 171b, a metal film member such as a nickel electroformed belt can be used. At this time, it is desirable that the inside (inner peripheral surface) be subjected to black oxidation treatment in order to absorb heat rays.

Further, a PFA (fluororesin) tube having a thickness of 30 to 100 μm is coated on the outer side (outer peripheral surface) of the heat ray absorbing layer 171b separately from the heat ray absorbing layer 171b to improve the releasability from the toner. Or fluorinated resin (PF
A or PTFE) Release layer 171c coated with a paint of 20 to 30 μm (having a thermal conductivity of (1 to 10) × 10 ⁻³ J / cm.
S · K, specific heat (（2.0) × J / g · K, specific gravity (〜0.9)) (separated type).

Further, as shown in the cross section in FIG. 5B, carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (Fe ₂ O ₃ ) and the like Heat-absorbing member mixed with powder of PTFE, and a fluororesin (PFA or PT) that also serves as a binder and a release agent
FE) paint is mixed and mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG.
A heat-fixing rotary member in the form of a roll having elasticity may be formed outside (outer peripheral surface) of the translucent elastic layer 171d formed outside (outer peripheral surface). The thermal conductivity of the dual-purpose layer 171Z is substantially the same as the thermal conductivity of the heat ray absorbing layer 171b.
(3-10) × 10 ⁻³ J / cm · s · K (specific heat
2.0) × J / g · K, and specific gravity is (０．９0.9).
As described above, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the translucent base 171a and the translucent elastic layer 171d are:
In order to completely absorb the heat rays transmitted through the light-transmitting base 171a and the light-transmitting elastic layer 171d, the heat ray absorptivity of the dual-purpose layer 171Z is set to 90 to 100%, which is about 100%, and preferably 95 to 100%. When the heat ray absorptivity in the dual-purpose layer 171Z is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the heat ray fixing rotating member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the heat ray fixing rotating member at a specific position due to, for example, mining, heat is generated from the adhering portion by the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the dual-purpose layer 171Z. When used for color image formation, the color toner absorption efficiency is generally low,
In addition, since there is a difference in the absorption efficiency between the color toners, a fixing failure occurs or fixing unevenness occurs. Therefore, the remaining heat rays emitted from the halogen lamp 171g or the xenon lamp (not shown) and absorbed by the light-transmitting base 171a and the light-transmitting elastic layer 171d form the light-transmitting base 171a and the light-transmitting elastic layer 171d. The combined layer 171Z has a heat ray absorptivity of about 90% to 100%, preferably about 100%, preferably 9 so that the heat rays transmitted through the heat ray fixing rotary member are completely absorbed in the heat ray fixing rotating member.
5 to 100%. Further, local heat generation in the dual-purpose layer 171Z is also prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the dual-purpose layer 171Z is 0.1 to 20 μm.
m, preferably 0.3 to 3 μm, so that a filler for adjusting hardness or thermal conductivity is added as a filler. 2
The average particle size including the secondary particles is 1 μm or less, preferably 0.1 μm or less.
Fine particles of metal oxide such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, calcium carbonate, etc. having a heat ray transmission of 1 μm or less (infrared ray or visible ray including visible light depending on the light source) are used as resin binder. May be formed to form the dual-purpose layer 171Z.

In the same manner as described above with reference to FIG. 6, if the concentration distribution of the heat ray absorbing member is uniformly provided on the heat ray absorbing layer 171b of the heat ray fixing roller 17a as a roll-shaped rotating member for heat ray fixing, the heat ray at the boundary is formed. Heat is concentrated in the absorption layer 171b, and the heat easily flows to the light-transmitting elastic layer 171d side. Therefore, the heat ray absorption layer 171b may be formed by using a lower heat conductive member than the light-transmitting substrate 171a or by providing a concentration distribution. It is preferable to generate heat inside from the viewpoint of dispersing the heat generation distribution. As shown in the graph (a), the concentration distribution of the heat ray absorbing layer 171b is set such that the interface on the side of the light-transmitting elastic layer 171d adjacent thereto has a low concentration, is gradually inclined toward the outer peripheral surface side, and is gradually increased. (Thickness t of heat ray absorbing layer 171b)
1/3 from the light-transmitting elastic layer 171d side.
(Position of about degree) so as to obtain a concentration that absorbs 100% so as to be saturated. Thereby, the heat ray absorbing layer 171b
As shown in the graph (b), the heat generation distribution due to the absorption of the heat ray at the point has a maximum value near the center of the heat ray absorption layer 171b and a minimum value near the interface and the outer peripheral surface of the heat ray absorption layer 171b. It is formed in a shape. Alternatively, the heat ray absorbing layer 171b
It is preferable to provide a light-transmissive heat-resistant resin (polyimide, fluororesin or silicon resin) with a thickness of 10 to 500 μm, preferably 20 to 100 μm on the interface or the outer peripheral surface of the substrate. Further, it is preferable to suppress heat loss as a member having a lower thermal conductivity than the translucent substrate 171a. This reduces heat generation due to absorption of heat rays at the interface, prevents heat from flowing out, and prevents damage to the adhesive layer and heat ray absorbing layer 171b at the interface. In addition, before the outer peripheral surface side (the heat ray absorbing layer 171).
2/3 from the light-transmitting base 171a side with respect to the thickness t1 of b.
(About ４ of the position) to saturate the concentration distribution from the outer peripheral surface to the outer peripheral surface. Note that a saturated layer may be formed as shown by a dotted line. In short, if the absorption is sufficiently performed inside, the influence of the concentration on the outside disappears. There is no influence of shaving. Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle.

In the same manner as described above with reference to FIG. 7, the outer diameter φ of the cylindrical light-transmitting substrate 171a of the heat ray fixing roller 17a as a roll-shaped heat ray fixing rotating member is 15 to
A thickness t of 60 mm is used. A thicker thickness t is better in terms of strength, and a thinner thickness is better in terms of heat capacity. However, from the relationship between strength and heat capacity, the thickness t is outside the cylindrical light-transmitting base 171a. The relationship between the diameter φ and the thickness t is 0.02 ≦ t / φ ≦ 0.20, and preferably 0.04 ≦ t / φ ≦ 0.10. When the outer diameter φ of the transparent substrate 171a is 40 mm, the thickness t of the transparent substrate 171a is 0.8 mm ≦ t ≦ 8 m.
m, preferably 1.6 mm ≦ t ≦ 4.0 mm. When t / φ is less than 0.02 in the translucent substrate 171a, the strength becomes insufficient, and when t / φ exceeds 0.20, the heat capacity increases and the heating of the heat ray fixing roller 17a is prolonged. Further, depending on the material, a light-transmitting substrate may absorb about 1 to 20% of heat rays, and it is preferable that the substrate be thin as long as the strength can be maintained.

As described above, by using the fixing device 670 of the sixth example described with reference to FIG. 21, the flat elastic roller and the lower elastic roller are placed between the upper soft roller and the lower elastic roller. The nip portion N is formed to fix the toner image. The heat generated in the heat ray absorbing layer 171b by the heat rays of the upper halogen lamp 171g and the xenon lamp (not shown), and the lower halogen lamp 171g and the xenon lamp ( Both the heat generated by the thin elastic fixing roller 47a (not shown) and the heat generated by the thin elastic fixing roller 47a,
The heat generated by the heat ray a can quickly raise the temperature of the heat ray absorbing layer 171b of the upper heat ray fixing roller 17a, thereby enabling high-speed fixing while saving energy and shortening the warming-up time, and at the same time, by using a uniform and stable temperature. An image forming apparatus that can achieve fixability can be obtained. Especially the upper soft roller having high elasticity (heat ray fixing roller 17a)
By fixing the toner image by using the above, high quality fixing (good fixing performance) is performed.

[0296]

According to the first aspect of the present invention, it is possible to realize a fixing device which enables high-speed fixing while achieving energy saving and shortens a warm-up time, and which can obtain a good fixing property with a uniform and stable temperature.

According to the second aspect, it is possible to realize an image forming apparatus which enables high-speed fixing while saving energy and shortening a warm-up time, and which can obtain good fixing properties at a uniform and stable temperature.

According to the third aspect, high-speed fixing of a surface toner image in double-sided image formation can be performed while energy saving and shortening of a warm-up time can be achieved, and a good surface toner image can be fixed at a uniform and stable temperature. It becomes possible.

According to the fourth aspect, it is possible to fix a color toner image at a high speed while saving energy and shorten a warm-up time, and it is also possible to fix a good color toner image at a uniform and stable temperature.

According to the fifth aspect, it is possible to realize a fixing device which enables high-speed fixing while saving energy and shortening a warm-up time, and which can obtain good fixing properties at a uniform and stable temperature.

According to the sixth aspect, it is possible to realize an image forming apparatus which enables high-speed fixing while saving energy and shortening a warm-up time, and which can obtain good fixing properties at a uniform and stable temperature.

According to the seventh aspect, high-speed fixing of a surface toner image in double-sided image formation can be performed while energy saving and shortening of a warm-up time can be achieved, and a good surface toner image can be fixed at a uniform and stable temperature. It becomes possible.

According to the eighth aspect, it is possible to fix a color toner image at a high speed while saving energy and shorten a warm-up time, and it is also possible to fix a good color toner image at a uniform and stable temperature.

According to the ninth aspect, it is possible to realize a fixing device which enables high-speed fixing while achieving energy saving and shortening of a warm-up time, and which can obtain good fixing properties at a uniform and stable temperature.

According to the tenth aspect, it is possible to realize an image forming apparatus which enables high-speed fixing while saving energy and shortening a warm-up time, and which can obtain good fixing properties with a uniform and stable temperature.

According to the eleventh aspect, high-speed fixing of a surface toner image in double-sided image formation is enabled while saving energy and shortening the warm-up time.
A good surface toner image can be fixed at a uniform and stable temperature.

According to the twelfth aspect, it is possible to fix a color toner image at a high speed while saving energy and shorten a warm-up time, and it is also possible to fix a good color toner image at a uniform and stable temperature.

[Brief description of the drawings]

FIG. 1 is a cross-sectional configuration diagram of an image forming apparatus showing an embodiment of a first example of an image forming apparatus according to the present invention.

FIG. 2 is a diagram illustrating a toner image forming state in the image forming apparatus of FIG. 1;

FIG. 3 is a sectional configuration diagram of a first example of a fixing device according to the present invention.

FIG. 4 is a detailed explanatory view of a fixing film.

FIG. 5 is an enlarged cross-sectional configuration diagram of the roll-shaped rotatable member for fixing heat rays in FIG. 3;

FIG. 6 is a diagram showing a concentration distribution of a heat ray absorbing layer of the roll-shaped heat ray fixing rotating member of FIG. 3;

FIG. 7 is a diagram showing the outer diameter and thickness of a light-transmitting substrate of the roll-shaped heat ray fixing rotating member of FIG.

FIG. 8 is a fixing control block diagram of the fixing device of FIG. 3 and fixing devices of the following examples.

FIG. 9 is a sectional configuration diagram of a color image forming apparatus showing an embodiment of a second example of the image forming apparatus according to the present invention.

FIG. 10 is a side sectional view of the image carrier of FIG. 9;

FIG. 11 is a cross-sectional configuration diagram of a second example of a fixing device according to the present invention.

FIG. 12 is a cross-sectional configuration diagram of an image forming apparatus showing an embodiment of a third example of the image forming apparatus according to the present invention.

FIG. 13 is a sectional configuration diagram of a third example of the fixing device according to the present invention.

FIG. 14 is a sectional configuration diagram of a color image forming apparatus showing an embodiment of a fourth example of the image forming apparatus according to the present invention.

FIG. 15 is a sectional configuration diagram of a fourth example of the fixing device according to the present invention.

FIG. 16 is a cross-sectional configuration diagram of an image forming apparatus showing an embodiment of a fifth example of the image forming apparatus according to the invention.

FIG. 17 is a sectional configuration diagram of a fifth example of the fixing device according to the present invention.

FIG. 18 is a diagram illustrating a layer configuration and a function of a fixing roller member.

FIG. 19 is a diagram illustrating a method of holding the fixing roller member.

FIG. 20 is a sectional configuration diagram of a color image forming apparatus showing an embodiment of a sixth example of the image forming apparatus according to the present invention.

FIG. 21 is a sectional configuration diagram of a sixth example of the fixing device according to the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 10 photoconductor drum 11 scorotron charger 12 exposure optical system 13 developing device 14A transport belt 14a intermediate transfer belt 14b primary transfer device 14c transfer device 14g secondary transfer device 17A, 27A, 37A, 47A heat fixing film 17a heat fixing roller 47a Thin plate elastic fixing roller 170, 270, 370, 470, 570, 670 Fixing device 171 Fixing film 172 Ceramic heater 171a Translucent substrate 171b Heat absorbing layer 171c Release layer 171d Translucent elastic layer 171g Halogen lamp 171Z Combined layer 372, 472 Magnetic body 373 Coil 471a Thin plate elastic roller 471j Resin bearing P Recording paper TS1, TS2, TS3 Temperature sensor

Continued on the front page F term (reference) 2H028 BC00 2H030 AD04 2H033 AA11 AA46 BA25 BB04 BB13 BB30 BE03

Claims (12)

[Claims] 1. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein: a film-shaped rotating member provided with a fixed heating element in contact with the film-shaped rotating member; A cylindrical light-transmitting base having a heat-ray irradiating means for emitting heat rays therein, and having a light-transmitting property with respect to the heat rays; and a light-transmitting elastic layer provided outside the light-transmitting base. And a heat-ray fixing rotating member having a heat-absorbing layer for absorbing the heat rays provided outside the translucent elastic layer. 2. An image forming apparatus for fixing and fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein: a film-shaped rotating member provided with a fixed heating element in contact therewith; A cylindrical light-transmitting base having heat-ray irradiating means for emitting heat rays, which is provided opposite to the member, and having a light-transmitting property with respect to the heat rays; An image forming apparatus, comprising: a fixing device including an elastic layer and a roll-shaped heat ray fixing rotating member provided with a heat ray absorbing layer that absorbs the heat ray outside the translucent elastic layer. 3. A fixing device for fixing a toner image transferred to both front and back surfaces of a transfer material, wherein the film-shaped rotating member corresponds to the toner image on the front surface.
An image forming apparatus according to claim 1. 4. An image forming apparatus for fixing and fixing a color toner image on a transfer material to the transfer material by heating and pressurizing, wherein the image forming apparatus has a heat ray irradiating means for emitting a heat ray therein, and is transparent to the heat ray. A roll provided with a light-transmitting cylindrical light-transmitting substrate, a light-transmitting elastic layer outside the light-transmitting substrate, and a heat-ray absorbing layer absorbing the heat rays outside the light-transmitting elastic layer. A fixing member comprising: a hot-beam fixing rotating member; and a film-shaped rotating member provided in contact with a fixed heating element provided opposite to the hot-wire fixing rotating member. An image forming apparatus, wherein a rotatable member for fixing heat rays is used. 5. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a film-shaped rotating member provided with an inductive heating element in contact with the film-shaped rotating member; A cylindrical light-transmitting base having a heat-ray irradiating means for emitting heat rays therein, and having a light-transmitting property with respect to the heat rays; and a light-transmitting elastic layer provided outside the light-transmitting base. And a heat-ray fixing rotating member having a heat-absorbing layer for absorbing the heat rays provided outside the translucent elastic layer. 6. An image forming apparatus for fixing and fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein: a film-shaped rotating member provided with an induction heating element in contact with the film-shaped rotating member; A cylindrical light-transmitting base having heat-ray irradiating means for emitting heat rays, which is provided opposite to the member, and having a light-transmitting property with respect to the heat rays; An image forming apparatus, comprising: a fixing device including an elastic layer and a roll-shaped heat ray fixing rotating member provided with a heat ray absorbing layer that absorbs the heat ray outside the translucent elastic layer. 7. A fixing device for fixing a toner image transferred to both front and back surfaces of a transfer material, wherein the film-shaped rotating member corresponds to a toner image on a front surface.
An image forming apparatus according to claim 1. 8. An image forming apparatus for fixing and fixing a color toner image on a transfer material to the transfer material by heating and pressurizing, wherein the image forming apparatus has a heat ray irradiating means for emitting heat rays therein, and is transparent to the heat rays. A roll provided with a light-transmitting cylindrical light-transmitting substrate, a light-transmitting elastic layer outside the light-transmitting substrate, and a heat-ray absorbing layer absorbing the heat rays outside the light-transmitting elastic layer. A fixing member comprising: a heat-irradiating rotating member having a shape; and a film-shaped rotating member provided with an induction heating element provided in contact with the heat-ray fixing rotatable member. An image forming apparatus, wherein a rotatable member for fixing heat rays is used. 9. A fixing device for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a fixing roller member made of a thin cylindrical elastic body is provided to face the fixing roller member. A heat-ray irradiating means for emitting heat rays inside, a cylindrical light-transmitting substrate having a light-transmitting property with respect to the heat rays, a light-transmitting elastic layer outside the light-transmitting substrate, A fixing device comprising a roll-shaped rotating member for fixing heat rays, wherein a heat ray absorbing layer for absorbing the heat rays is provided outside a photoelastic layer. 10. An image forming apparatus for fixing and fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a fixing roller member made of a thin cylindrical elastic body is opposed to the fixing roller member. A cylindrical light-transmitting base having a heat-ray irradiating means for emitting heat rays therein, and having a light-transmitting property with respect to the heat rays; and a light-transmitting elastic layer provided outside the light-transmitting base. An image forming apparatus comprising: a fixing device including a roll-shaped heat ray fixing rotating member provided with a heat ray absorbing layer that absorbs the heat ray outside the translucent elastic layer. 11. A fixing device for fixing a toner image transferred on both front and back surfaces of a transfer material, wherein the fixing roller member corresponds to the toner image on the front surface.
An image forming apparatus according to claim 1. 12. An image forming apparatus for fixing and fixing a color toner image on a transfer material to the transfer material by heating and pressurizing, wherein the image forming apparatus has a heat ray irradiating means for emitting heat rays therein, and is transparent to the heat rays. A roll provided with a light-transmitting cylindrical light-transmitting substrate, a light-transmitting elastic layer outside the light-transmitting substrate, and a heat-ray absorbing layer absorbing the heat rays outside the light-transmitting elastic layer. And a fixing roller member formed of a thin cylindrical elastic body and provided opposite to the heat ray fixing rotating member, the heat ray fixing to the color toner image. An image forming apparatus, wherein a rotary member for use corresponds.