JPH11327342A - Fixing roller member and fixing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make a heat ray for quick start fixing obtainable, by which instantaneous heating can be executed and whose heating time is short by providing a heat ray absorption layer absorbing almost all the heat ray on the outside of shaped light transmissive base substance. SOLUTION: A 1st heat ray fixing roller 17a is provided with a shaped light transmissive base substance 171A obtained by forming and shaping a heat resistant resin layer 171e outside a cylindrical light transmissive base substance 171a, a heat ray absorption layer 171b outside the substance 171A, and further a mold-released layer 171c outside the layer 171b. The layer 171b absorbs the heat ray emitted from a heat ray irradiation member 171g and transmitted through the substance 171A by 90 to 100%, desirably, 95 to 100% equivalent to about 100%. Namely, a heat absorption member obtained by mixing the powder of carbon black, black lead, iron black and ferrite of every kind in resin binder is used so that the fixing roller member capable of the instantaneous heating may be formed, and it is formed outside the substance 171A by baking after its thickness is set to 10 to 200 μm, desirably, 20 to 100 μm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing roller member and a fixing device used for an image forming apparatus such as a copying machine, a printer, a facsimile, etc., and more particularly to a fixing roller member and a fixing device for quick start fixing capable of instantaneously heating. About.

[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 the conventional heat roller fixing type fixing device, it is necessary to heat the fixing roller having a large heat capacity when heating the transfer material or the toner. In addition, 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, 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 temperature-controlled heater (ceramic heater) is directly applied to the heat fixing film. A fixing device of a film fixing type has been proposed and used recently, in which heat conduction efficiency is greatly improved by contact with pressure, and energy saving and a quick start requiring almost no warm-up time are achieved.

Japanese Patent Application Laid-Open No. 52-106741 discloses a method in which a heat-transferable substrate is used as a fixing roller as a modification of a heat roller, and a toner is irradiated with heat rays from a halogen lamp provided therein to heat and fix the toner. No. 57-82240, No. 57-102736, No. 57-10274
No. 1 and the like.

[0006]

However, in the fixing device using the heat fixing film according to the above proposal, although energy saving and a quick start in which the warming up time is shortened are achieved, a fixing device having a zero warming up time by instantaneous heating is used. There is a problem in that the toner image cannot be obtained or stable running of the heat fixing film cannot be obtained, and a deviation occurs when fixing the toner image on the transfer material due to deformation of the heat fixing film in the fixing unit.

[0007] In particular, in the method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 52-106741 or the like, a glass pipe or a light-transmitting substrate mainly using a polyimide resin or the like is used as a substrate of the fixing roller. Heat resistance, strength,
Although the light-transmitting property is good, irregularities are formed on the outer peripheral surface of the light-transmitting substrate, and the accuracy of roundness of the outer diameter is poor, so that the fixing becomes uneven or the transfer material has wrinkles. There is a problem that occurs. Further, the toner easily adheres to the uneven portion or the deformed portion or filming easily occurs. If the toner is adhered or filmed, only this portion is particularly easily heated, and the fixing becomes uneven. Further, the toner is restricted due to heat ray absorption. That is, there is a problem that the color toner has a poor light absorption property and is difficult to apply.

The present invention solves the above-mentioned problems and provides a fixing roller member for quick start fixing capable of instantaneous heating or having a short heating time by obtaining a highly accurate translucent substrate having an outer diameter. It is another object of the present invention to provide a fixing device that uses a heating wire for quick start fixing that allows instantaneous heating or has a short heating time without causing fixing unevenness and fixing wrinkles.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a fixing roller member for fixing a toner image on a transfer material to the transfer material by heating and pressurizing, wherein a cylindrical light-transmitting member having a property of transmitting heat rays is provided. A heat-resistant resin layer is formed outside the light-transmitting substrate, and the heat-resistant resin layer is shaped to form a shaped light-transmitting substrate. (1st invention).

Another 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 heat ray irradiating means for emitting a heat ray is disposed inside, and the heat ray is transmitted to the heat ray. Providing a cylindrical translucent substrate having optical properties,
Forming a heat-resistant resin layer outside the light-transmitting substrate, shaping the heat-resistant resin layer into a shaped light-transmitting substrate, and then providing a heat ray absorbing layer outside the shaped light-transmitting substrate. This is achieved by a fixing device which is a feature of the present invention (second invention).

[0011]

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. Also, the following assertive description in the embodiment of the present invention indicates the best mode, and does not limit the meaning of the terms of the present invention or the technical scope. In the following description of the embodiment, in the transfer area, the surface (upper surface) of the transfer material on the side facing the image forming body is the front surface, and the other surface of the transfer material, that is, the transfer material on the side facing the intermediate transfer body. The surface (lower surface) 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.

An image forming process and each mechanism of an embodiment of an image forming apparatus using a fixing device according to the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a color image forming apparatus showing an embodiment of an image forming apparatus using a fixing device according to the present invention, and FIG. 2 is a view showing a toner image forming state in the image forming apparatus of FIG. FIG. 2A is a diagram showing a toner image formation state when a back surface image formed on the image forming body is transferred onto the intermediate transfer body, and FIG. FIG. 2C is a diagram illustrating a toner image formation state when a front surface image is formed on an image forming body in synchronization with a back surface image, and FIG. 2C is a diagram illustrating double-sided image formation on a transfer material; FIG. 4 is a diagram illustrating an example of a document image reading unit, FIG. 4 is a control circuit block diagram of the image forming apparatus, and FIG. 5 is an explanatory diagram illustrating a structure of a first example of the fixing device. 6 is an enlarged cross-sectional configuration diagram of the upper fixing roller member of FIG. 5, and FIG. FIG. 8 is a diagram illustrating a concentration distribution of a heat ray absorbing layer of a fixing roller member, and FIG. 9 is a diagram illustrating an outer diameter and a thickness of a light-transmitting substrate of the fixing roller member. is there.

As shown in FIGS. 3 and 4, a document image reading device 500 as a document image reading means includes a reading device main body 501, a document storage plate 505 for storing a document PS, a document sending roller 502, a transparent plate 503. , Document feed roller 504, document discharge tray 506, and transparent plate 503
And a line-shaped document image reading sensor PS1 and PS2 for reading the document image of the document PS from above and below. The control unit is controlled by a signal line incorporated in an external device or a color image forming apparatus described below. Connected.

When the original PS sent by the original sending roller 502 passes through the transparent plate 503, the original PS is converted to a one-sided original by original image reading sensors PS1 and PS2 provided above and below the transparent plate 503. Determination of whether the document is a double-sided document (single-sided or double-sided) and reading of image data of the document PS are performed.

In this embodiment, one-sided / two-sided discrimination and image data reading are performed by one set of upper and lower sensors. However, a plurality of sensors respectively corresponding to image data reading and one-sided / two-sided discrimination may be provided. For example, image data may be read after a single-sided or double-sided discrimination has been performed using a plurality of sensors respectively corresponding to each other. Original image reading sensor PS1
Alternatively, the image data of one bundle of originals PS is read by PS2 and stored in the RAM through the control unit.

When the image is determined to be a double-sided image,
The image data of the document PS is read by the document image reading means shown in FIG. 3, and the double-sided image forming program P1 stored in the ROM shown in FIG. P1 is executed, and the image forming process is performed.

1 and 2, reference numeral 10 denotes a photosensitive drum as an image forming body, 11 denotes a scorotron charger as a charging unit for each color, and 12 denotes an exposure optical system as an image writing unit for each color. , 13 are developing devices as developing means for each color, 14
a is an intermediate transfer belt that is an intermediate transfer member, 14c is a transfer device that is a first and a second transfer unit, 14g is a back surface transfer device that is a third transfer unit, 14m is a charge remover that is a charge removing unit,
Reference numeral 150 denotes a paper charger serving as a transfer material charging unit, 14 h denotes a paper separation AC static eliminator serving as a transfer material separating unit, 160 denotes a transport unit having a separation claw 210 serving as a claw member and a spur 162 serving as a spur member, and 169 denotes a spur member. An entry guide plate 17 as an entry guide member is the fixing device of the first example.

The photosensitive drum 10, which is an image forming body, 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 (also referred to as a photoconductive layer) such as an Si layer or an organic photosensitive layer (OPC), which is rotated clockwise as indicated by an arrow in FIG. 1 with the conductive layer grounded.

A scorotron charger 11, which is a charging unit for each color, an exposure optical system 12, which is an image writing unit for each color, and a developing unit 13, which is a developing unit for each color, form a set of yellow (Y) ), Magenta (M), cyan (C), and black (K) are provided for the image forming process, and four sets are provided.
With respect to the 0 rotation direction, they are arranged in the order of Y, M, C, and K.

The scorotron charger 11, which is a charging means for each color, has a control grid maintained at a predetermined potential and a discharge electrode 11a composed of, for example, a sawtooth electrode, and faces the photosensitive layer of the photosensitive drum 10. And installed
The charging operation (in the present embodiment, negative charging) is performed by corona discharge having the same polarity as that of the toner.
A uniform potential is given to 0. As the discharge electrode 11a, a wire electrode or a needle electrode may be used.

Exposure optical system 1 as image writing means for each color
2 indicates that the exposure position on the photosensitive drum 10 is the photosensitive drum 1 with respect to the scorotron charger 11 for each color described above.
It is arranged inside the photoconductor drum 10 so as to be located on the downstream side in the rotation direction of 0. Each exposure optical system 12
Is a linear exposure element 12a in which a plurality of LEDs (light emitting diodes) as light emitting elements of image exposure light arranged in the main scanning direction are arranged in parallel with the drum axis, and a light focusing element as an imaging element. Exposure unit composed of an optical transmission body (trade name: Selfoc lens array) 12b and a lens holder (not shown), which is attached to the holding member 20. In addition to the exposure optical system 12 for each color, a transfer simultaneous exposure unit 12d and a uniform exposure unit 12e are attached to the holding member 20, and are housed integrally within the light-transmitting substrate of the photosensitive drum 10. The exposure optical system 12 for each color performs image exposure of the photosensitive layer of the photosensitive drum 10 from the back side in accordance with image data of each color read by a separate image reading device and stored in the memory, and electrostatically exposes the photosensitive layer on the photosensitive drum 10. Form a latent image. As the exposure element 12a, besides LED, FL (phosphor emission), EL (electroluminescence), PL
It is also possible to use a plurality of light-emitting elements such as (plasma discharge) arranged in an array. The emission wavelength of the image exposure light emitting element usually ranges from 780 to 900 nm, which is highly transparent to the Y, M, and C toners.
In the present embodiment, since the image exposure is performed from the back surface, a shorter wavelength of 400 to 780 nm, which does not have sufficient transparency to the color toner, may be used. Most of the image exposure light is absorbed by the photosensitive layer.

The developing device 13 as a developing means for each color 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, for example, 0.5 to 1 mm in thickness. And a developing casing 131 formed of a cylindrical nonmagnetic stainless steel or aluminum material having an outer diameter of 15 to 25 mm, and a developing casing 138. Inside the developing casing 138, yellow (Y) and magenta ( M), cyan (C) and black (K) one-component or two-component developers. Each developing unit 13
Is maintained in a non-contact state with the photosensitive drum 10 with a predetermined gap, for example, 100 to 500 μm, by an abutting roller (not shown), and applies a developing bias in which a DC voltage and an AC voltage are superimposed on the developing sleeve 131. By doing
Non-contact reversal development is performed to form a toner image on the photosensitive drum 10.

The intermediate transfer belt 14a as an intermediate transfer member has a volume resistivity of ¹⁰ 10 Ω · cm to 10 ¹⁶ Ω · cm, preferably ¹⁰ 10 Ω · cm.
It is an endless belt of ¹² to 10 ¹⁵ Ωcm, for example, a modified polyimide, a thermosetting polyimide, an ethylene tetrafluoroethylene copolymer, polyvinylidene fluoride, a thickness of 0.1 in which a conductive material is dispersed in an engineering plastic such as nylon alloy. This is a seamless belt having a two-layer structure in which a fluorine coating having a thickness of 5 to 50 μm is preferably formed on the outside of a semiconductive film substrate having a thickness of 1.0 to 1.0 mm, preferably as a toner filming preventing layer. As the base of the belt,
In addition, a semiconductive rubber belt having a thickness of 0.5 to 2.0 mm in which a conductive material is dispersed in silicon rubber, urethane rubber, or the like can be used. Intermediate transfer belt 14a
Are stretched in contact with a driving roller 14d, a ground roller 14j, a driven roller 14e, and a tension roller 14i, which are roller members, respectively, and are rotated in a counterclockwise direction indicated by an arrow in FIG. The driven roller 14e, the ground roller 14j, the drive roller 14d, and the tension roller 14i are provided in this order according to the rotation direction of the intermediate transfer belt 14a, and the driven roller 14e, the ground roller 14j, and the drive roller 1
4d is fixedly rotated, the tension roller 14i is movably supported by elasticity such as a spring (not shown), and the tension roller 14i is rotated while stretching the intermediate transfer belt 14a. The drive roller 14d is rotated by a drive from a drive motor (not shown), and drives and rotates the intermediate transfer belt 14a. The rotation of the intermediate transfer belt 14a causes the ground roller 14j, the driven roller 14e, and the tension roller 14i to be driven and rotated. Belt slack of the rotating intermediate transfer belt 14a is tensioned by the tension roller 14i. 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 17 side.

Transfer device 14 as first and second transfer means
c denotes the photosensitive drum 10 with the intermediate transfer belt 14a interposed therebetween.
A transfer area 14b is formed 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 transfer device 14c, and the toner image on the photosensitive drum 10 is transferred onto the intermediate transfer belt 14a or onto the surface of the recording paper P as a transfer material. Transcribe.

The back transfer unit 14g, which is a third transfer means, is preferably constituted by a corona discharger, and is a conductive ground roller 14 grounded with the intermediate transfer belt 14a interposed therebetween.
j, a DC voltage having a polarity opposite to that of the toner (positive polarity in the present embodiment) is applied, and the toner image on the intermediate transfer belt 14a is transferred to the back surface of the recording paper P.

The static eliminator 14m, which is a static eliminator, is preferably constituted by a corona discharger, and is disposed downstream of the transfer unit 14c, which is the first and second transfer unit, in the moving direction of the intermediate transfer belt 14a. 14c is provided in parallel with
An AC voltage on which a DC voltage having the same polarity or opposite polarity to the toner is superimposed is applied, and the charge of the intermediate transfer belt 14a charged by the voltage application of the transfer device 14c is eliminated.

The paper charger 150, which is a transfer material charging means, is preferably constituted by a corona discharger, and is provided to face the driven roller 14e with the intermediate transfer belt 14a interposed therebetween.
Same polarity as toner (minus polarity in this embodiment)
Is applied, and the recording paper P is charged and attracted to the intermediate transfer belt 14a. In addition to the corona discharger, a paper charging brush or a paper charging roller that can abut and release the intermediate transfer belt 14a can be used as the paper charger 150.

Paper separation AC neutralizer 1 as transfer material separating means
4h is preferably formed of a corona discharger, and is provided at an end of the intermediate transfer belt 14a on the side of the fixing device 17 as needed, facing the conductive drive roller 14d grounded with the intermediate transfer belt 14a interposed therebetween. If necessary, an AC voltage in which a DC voltage having the same polarity or opposite polarity to the toner is superimposed is applied, and 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 includes a separation claw 210 as a claw member.
And a spur member 162 serving as a spur member. The spur member 162 is provided between the fixing device 17 and the curvature portion KT at the end of the intermediate transfer belt 14a on the fixing device 17 side. The transport unit 160 includes the fixing device 1
7, the intermediate transfer belt 14a is deformed, the toner image carried on the intermediate transfer belt 14a tends to be fused, and the transfer is difficult.
4a is prevented from sticking to the toner.

The separation claw 210, which is a claw member, approaches the curvature portion KT of the intermediate transfer belt 14a, and
The recording paper P is fixed to the support shaft 221 with a predetermined interval, preferably 0.1 to 2.0 mm, provided when the recording paper P is separated from the intermediate transfer belt 14a.
The leading end of the recording paper P that is to be conveyed while being bent in the direction a is brought into contact with the recording paper P to assist the 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 transfers the recording sheet P to the fixing device 17. The recording paper P is stably conveyed to the fixing device 17 while keeping the entering direction constant.

The separation claw 210 and the spur 162 are connected to the curvature portion KT of the intermediate transfer belt 14a and the nip portion T of the fixing device 17.
The surface of the photoconductor drum 1 with respect to a surface PL1 (hereinafter referred to as a transfer material transport surface PL1) connecting an entrance portion (entry portion) of the transfer material to the photoconductor drum 1
On the side opposite to 0, it is disposed in contact with or close to the transfer material transport surface PL1. It is also possible to provide spurs 162 as spur members on both sides of the transfer material transport surface PL1.

An entry guide plate 169 serving as an entry guide member
Is disposed in contact with or close to the transfer material transport surface PL1 on the opposite side of the photosensitive drum 10, and the leading end guides the recording paper P so that the leading end of the recording paper P is prevented from wrinkling during fixing. The fixing device 17 is caused to enter the nip portion T.

The fixing device 17 of the first example is an upper side (front side) for fixing a toner image of a front side image (upper side image).
First heat ray fixing roller 17 used as a fixing roller member
a and a first fixing roller 47a used as a lower (rear side) fixing roller member for fixing a toner image of a back side image (image on the lower side), between the upper and lower fixing roller members. The recording paper P is sandwiched between the formed nip portions T, and heat and pressure are applied to fix the toner image on the recording paper P.

Next, the image forming process will be described.

The photosensitive drum 10 is rotated clockwise as indicated by an arrow in FIG. 1 by starting a photosensitive member driving motor (not shown) at the start of image recording, and is simultaneously exposed to light by the charging action of a yellow (Y) scorotron charger 11. Body drum 1
Application of a potential to 0 starts.

After the photosensitive drum 10 is applied with a potential, the Y exposure optical system 12 starts image writing with a first color signal, that is, an electric signal corresponding to the Y image data. An electrostatic latent image corresponding to the Y image of the original image is formed on the front surface.

The latent image is reversal-developed in a non-contact state by the Y developing unit 13, and a yellow (Y) toner image is formed on the photosensitive drum 10.

Next, a potential is applied to the photosensitive drum 10 from above the Y toner image by the charging action of the magenta (M) scorotron charger 11, and the second color signal, that is, the M color signal, is applied by the M exposure optical system 12. Image writing is performed by an electric signal corresponding to the image data, and the magenta (M) toner image is superimposed on the yellow (Y) toner image by non-contact reversal development by the M developing unit 13. It is formed.

By the same process, the cyan (C) toner image corresponding to the third color signal is further superimposed by the cyan (C) scorotron charger 11, the exposure optical system 12 of C and the developing device 13 of C. The black (K) toner image corresponding to the fourth color signal is sequentially superimposed thereon by a black (K) scorotron charger 11, a K exposure optical system 12, and a K developing device 13. A superposed color toner image of four colors of yellow (Y), magenta (M), cyan (C) and black (K) is formed on the peripheral surface within one rotation of the photosensitive drum 10. (Toner image forming means).

These Y, M, C and K exposure optical systems 12
Image writing on the photosensitive layer of the photosensitive drum 10 is performed from the inside of the drum through the above-described translucent substrate. Therefore, the writing of the images corresponding to the second, third and fourth color signals is performed without any influence from the previously formed toner image, and is equivalent to the image corresponding to the first color signal. Can be formed.

In the transfer area 14b, the superimposed color toner image serving as the back surface image formed on the photosensitive drum 10 as the image forming body by the above-described image forming process is formed.
By the transfer device 14c as a first transfer unit, the transfer (1) is collectively performed on the intermediate transfer belt 14a as the intermediate transfer body.
The next transfer is performed (FIG. 2A). At this time, uniform exposure may be performed by the simultaneous transfer exposure device 12d provided inside the photoconductor drum 10 so that good transfer is performed.

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 forming body cleaning means. 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 toner discharge container (not shown). Further, the peripheral surface of the photosensitive drum 10
For example, a uniform exposure device 12 before charging using a light emitting diode
The history of the photosensitive drum 10 in the previous image formation is eliminated by the exposure by e.

The charge on the intermediate transfer belt 14a charged by the transfer unit 14c is removed by a charge removal unit 14m which is a charge removal unit provided in parallel with the transfer unit 14c.

After the superimposed color toner image (second toner image) serving as the back surface image is formed on the intermediate transfer belt 14a as described above, the above-described color image forming process is performed on the photosensitive drum 10. Similarly, a superimposed color toner image (first toner image) to be a surface image continuously
Is formed (FIG. 2B). At this time, the photosensitive drum 1
The image data is changed so that the front side image formed on 0 is a mirror image of the back side 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
5b, and driven by the timing roller 15b, the first toner image formed on the photosensitive drum 10 is a surface toner color toner image and the intermediate transfer belt 14
The sheet is fed to the transfer area 14b in synchronization with the color toner image of the back side image, which is the second toner image carried on the transfer area 14b. At this time, the fed recording paper P is charged to the same polarity as the toner by a paper charger 150 which is a transfer material charging means provided on the surface side of the recording paper P, and the intermediate transfer belt 14a
And is fed to the transfer area 14b. By charging the paper with the same polarity as that of the toner, the toner 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 14b, a second voltage to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied.
The surface image on the photosensitive drum 10 is collectively transferred to the surface of the recording paper P by the transfer device 14c as the transfer means (2).
Next transfer). At this time, the back side image on the intermediate transfer belt 14a is not transferred to the recording paper P, and the intermediate transfer belt 1
4a. Transfer device 14 as second transfer means
In the case of secondary transfer by c, so that good transfer is performed,
The uniform exposure may be performed by a simultaneous transfer exposure device 12d using, for example, a light emitting diode, provided inside the photosensitive drum 10 so as to face the transfer area 14b. Further, the intermediate transfer belt 14a charged by the transfer device 14c
Is removed by the charge remover 14m.

The recording paper P on which the color toner image has been transferred to the front surface is conveyed to a back transfer device 14g as a third transfer means to which a voltage having a polarity opposite to that of the toner (positive polarity in this embodiment) is applied. Then, the back side image on the peripheral surface of the intermediate transfer belt 14a is collectively transferred (tertiary transfer) to the back side of the recording paper P by the back side transfer unit 14g (FIG. 2C).

The recording paper P on which the color toner images are formed on both sides is formed by the curvature of the curvature portion KT of the intermediate transfer belt 14a and the paper as transfer material separating means provided at the end of the intermediate transfer belt 14a as necessary. The spur 162 provided on the transport unit 160 is separated from the intermediate transfer belt 14a by the static elimination action of the separation AC neutralizer 14h and the separation claw 210 provided on the transport unit 160 at a predetermined interval from the intermediate transfer belt 14a. Then, the toner image is stably conveyed to the fixing device 17 through the entry guide plate 169, and the leading end portion is sent to the nip portion T of the fixing device 17 by the entry guide plate 169 to fix the toner image of the surface image (upper image). A first heat ray fixing roller 17a disposed on the upper side, and a first fixing roller disposed on the lower side for fixing a toner image of a back image (lower image) The toner image on the recording sheet P is fixed by being added to the heat and pressure at the nip portion T between 7a. 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. Further, as shown by a dashed line in FIG. 1, a switching member (not shown) may be provided at the exit of the fixing device 17 so that the sheet is discharged to a tray outside the device without turning over.

The toner remaining on the peripheral surface of the intermediate transfer belt 14a after the transfer is provided opposite to 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 removed by a photoreceptor drum AC static eliminator 16 and then cleaned by a cleaning device 19. By 12e, the history of the photosensitive drum 10 in the previous image formation is eliminated, and the next image formation cycle is started.

Since the superimposed color toner images are collectively transferred by using the above-described method, color shift of the color image on the intermediate transfer belt 14a, scattering or rubbing of the toner, and the like are less likely to occur, and the image deterioration is small. Double-sided color image formation is performed.

In the original image reading apparatus 500,
When the image data of the document PS read by the document image reading unit shown in FIG. 3 is copied as a single-sided image of only the surface of the photosensitive drum 10 when the image is determined to be a single-sided image or a double-sided image The RO shown in FIG.
A single-sided image forming program P2 of the front surface by the photosensitive drum 10 as an image forming body stored in M is read into the RAM through the control unit, and the single-sided image forming program P2 of the front surface is executed by the control unit. The described image forming process of only the surface by the photosensitive drum 10 is continuously performed.

When the image data is determined to be a single-sided image or a double-sided image, the image data of the original PS read by the original image reading means shown in FIG. In the case of copying as an image, a single-sided image forming program P3 on the back surface of the intermediate transfer belt 14a as an intermediate transfer member stored in the ROM shown in FIG. The image forming program P3 is executed, and the image forming process for only the back surface by the intermediate transfer belt 14a described in FIG. 1 is continuously performed.

Although the embodiment of the image forming apparatus using the fixing device of the present invention has been described with reference to color image formation, the present invention is not necessarily limited to this, and will be described with reference to FIGS. 1 and 2. The present invention is also applicable to monochrome single-sided or double-sided image formation by the same process as described above. Further, although the embodiment of the image forming apparatus using the fixing device of the present invention has been described with reference to the double-sided image forming apparatus, the present invention is not necessarily limited to this, and the fixing device described below is also applicable to the double-side fixing. However, the present invention is not limited to this, and is also used as a fixing device for one side.

As shown in FIG. 5, the fixing device 1 of the first example
Reference numeral 7 denotes a first roller used as an upper (front surface) fixing roller member for fixing a toner image of a front surface image (upper surface side image).
It is composed of a heat ray fixing roller 17a and a first fixing roller 47a used as a lower (rear side) fixing roller member for fixing a toner image of a back side image (lower side image). The recording paper P is sandwiched between the nip portions T formed between the recording paper P and the toner image on the recording paper P is fixed by applying heat and pressure.

First heat ray fixing roller 17 used as an upper fixing roller member for fixing a toner image of a front surface image
a shows a case where a heat-resistant resin layer 171e is formed on the outside (outer peripheral surface) of a cylindrical light-transmitting substrate 171a, and the heat-resistant resin layer 171e is formed.
171A, a heat-absorbing layer 171b outside (outer peripheral surface) of the cylindrical shaped translucent substrate 171A, and a heat-ray absorbing layer 171b outside (outer peripheral surface) of the heat-ray absorbing layer 171b. And a mold layer 171c, and inside the shaped translucent substrate 171A, a heat ray irradiating member 171g as a heat ray irradiating means using, for example, a halogen lamp or a xenon lamp.
Are arranged as hard rollers. The heat ray emitted from the heat ray irradiating member 171g is absorbed by the heat ray absorbing layer 171b to form a fixing roller member capable of instantaneously heating (first example of a fixing roller member for instantaneous heating).

Further, the first fixing roller 4 used as a lower fixing roller member for fixing the toner image of the back surface image.
7a is a cylindrical metal pipe 4 made of, for example, an aluminum material.
And a rubber roller 471b having a thickness of 2 to 20 mm using, for example, a silicon material on the outer peripheral surface of the metal pipe 471a.
And a soft roller in which a halogen heater 471c is disposed inside a metal pipe 471a. A nip portion T having a convex lower side is formed between the upper hard roller and the lower soft roller, and the toner image is fixed.

TS1 is the upper first heat ray fixing roller 17a
Is a temperature sensor using, for example, a thermistor for performing temperature control, and TS2 is a temperature sensor using, for example, a thermistor for performing temperature control, which is mounted on the lower first fixing roller 47a.

According to FIG. 7, a cylindrical light-transmitting substrate 171 is provided.
a heat-resistant resin layer 171e is formed outside (outer peripheral surface)
The heat-resistant resin layer 171e is shaped to produce a cylindrical shaped translucent substrate 171A.

First, as a first method, a heat-resistant resin is coated on the outer peripheral surface of the cylindrical light-transmitting substrate 171a,
Heat-induced polymerization or solvent removal to form a cylindrical heat-resistant resin layer 1
After the formation of the heat-resistant resin layer 171e, the outer peripheral surface of the heat-resistant resin layer 171e is formed so that the outer peripheral surface has a roundness with respect to the central axis of the inner peripheral surface of the light-transmitting substrate 171a. Is cut and polished to form a cylindrical shaped translucent substrate 171A.

As a second method, an outer peripheral surface of a cylindrical light-transmitting substrate 171a is coated with a heated and melted resin liquid, and cooled to form a heat-resistant resin layer 171e. The outer peripheral surface of the heat-resistant resin layer 171e is cut and polished so that the outer peripheral surface has a roundness on the basis of the center axis of the inner peripheral surface and the outer peripheral surface is a smooth surface. The conductive base 171A is formed.

As a third method, a silicon tube is placed on the outer peripheral surface of the cylindrical light-transmitting substrate 171a, and the heat-shrinkable heat-resistant resin layer 171e is formed.
The outer peripheral surface of the heat-resistant resin layer 171e is cut and polished so that the outer peripheral surface has a roundness based on the center axis of the inner peripheral surface of the inner peripheral surface 71a and the outer peripheral surface is smooth. The light-transmitting substrate 171A is formed.

By the above processing, a smooth and highly accurate cylindrical light-transmitting substrate having no irregularities using a heat-resistant resin can be obtained. That is, it is possible to obtain a cylindrical shaped translucent substrate having no irregularities and having a smooth and high precision roundness.

According to FIG. 6, the first heat ray fixing roller 17a
6A, as shown in the cross section in FIG. 6A, the cylindrical light-transmitting base 171A of the cylindrical shaped light-transmitting base 171A has an outer diameter φ of 15 to 60 mm and a thickness t of 2 mm. -10m
m, a translucent resin using a ceramic material such as Pyrex glass, sapphire (Al ₂ O ₃ ), or CaF ₂ , or a polyimide or polyamide that transmits heat rays such as infrared rays or far infrared rays from the heat ray irradiation member 171 g. And so on. The wavelength of the heat ray passing through the translucent substrate 171a is 0.1 to 20 μm, and preferably 0.3 to 3 μm. Therefore, an adjuster for hardness and thermal conductivity is added as a filler,波長, preferably の of the wavelength of
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having a heat ray transmission (mainly infrared or far infrared ray transmission) of 1 μm or less, preferably 0.1 μm or less,
Fine particles of metal oxides such as magnesium oxide and calcium carbonate are dispersed in a resin binder.
1a may be formed. It is preferable that the layer φ has an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles, in order to prevent light scattering and allow heat rays to reach the heat ray absorption layer 171b.

As the heat-resistant resin layer 171e of the cylindrical shaped light-transmitting substrate 171A, a light-transmitting resin using polyimide, polyamide, or the like is used, and a cutting allowance for the surface layer of the light-transmitting substrate 171a can be obtained. Thickly applied, the thickness after cutting is 50-1000 μm, preferably 100-500
μm. The wavelength of the heat ray passing through the heat-resistant resin layer 171e is 0.1 to 20 μm, preferably 0.3 to 3 μm.
Since it is μm, an agent for adjusting hardness and thermal conductivity is added as a filler, but the average particle size including primary and secondary particles having a particle size of １ ／, preferably １ ／ or less, of the wavelength of the hot wire Fine particles of a metal oxide having a diameter of 1 μm or less, preferably 0.1 μm or less, such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate, having a heat ray transmission property (mainly infrared or far infrared ray transmission property). A heat-resistant resin layer 171 dispersed in a resin binder
e may be formed. It is preferable that the average particle size including the primary and secondary particles is 0.1 to 1 μm or less to prevent light scattering and allow the heat rays to reach the heat ray absorbing layer 171b.

The heat ray absorbing layer 171b is formed by forming a heat resistant resin layer 171e on the outer side (peripheral surface) of the light transmissive substrate 171a, emitting light from the heat ray irradiating member 171g, and shaping the heat resistant resin layer 171e. 90 to 100%, preferably 95 to 100% of the heat rays corresponding to substantially 100% of the heat rays transmitted through the conductive base 171A are absorbed by the heat ray absorbing layer 171b to form a fixing roller member capable of instantaneously heating. Carbon black, graphite, iron black (F
e ₃ O ₄ ), various ferrites and compounds thereof, copper oxide, cobalt oxide, heat ray absorbing members mixed with powder such as red iron oxide (Fe ₂ O ₃ ), and has a thickness of 10 to 200 μm, preferably 20 to 100 μm. The heat ray absorbing member is formed on the outer side (outer peripheral surface) of the shaped translucent substrate 171A by baking or coating. The heat ray absorption rate in the heat ray absorption layer 171b is 90
%, For example, about 20 to 80%, the heat rays leak, and when the first heat ray fixing roller 17a as the fixing roller member is used for monochrome image formation due to the leaked heat rays, the heat rays leak due to filming or the like. 1 heat ray fixing roller 1
When the black toner adheres to the surface of the specific position 7a, heat is generated from the adhering portion due to the leaked heat rays, and the heat generated by the absorption of heat rays is further superimposed on that portion, thereby damaging the heat ray absorbing layer 171b. Further, 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, the heat ray absorption rate of the heat ray absorbing layer 171b is approximately 100% so that the heat rays emitted from the heat ray irradiation member 171g and transmitted through the shaped translucent substrate 171A are completely absorbed in the first heat ray fixing roller 17a. ~ 1
00%, preferably 95 to 100%. Further, when the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate by the absorption of the heat ray in the heat ray absorbing layer 171b is high,
If the thickness of the heat ray absorbing layer 171b exceeds 200 μm and becomes too thick, heat conduction becomes poor or the heat capacity increases, and instantaneous heating may occur. It is difficult to achieve. 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 10 to 200 μm, preferably 20 to 100 μm,
Local heat generation in 1b is prevented, and uniform heat generation is performed. Further, 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, an adjusting agent of hardness or thermal conductivity is added as a filler, 1/2 of the wavelength of the heat ray, preferably 1/5
Titanium oxide, aluminum oxide, zinc oxide, silicon oxide having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles below, having heat ray transmission properties (mainly infrared or far infrared ray transmission properties) The fine particles of metal oxides such as magnesium oxide, calcium carbonate and the like are dispersed in a resin binder in an amount of 5 to 50% by weight.
1b may be formed.

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 171 b separately from the heat ray absorbing layer 171 b in order to improve the releasability from the toner. Or fluorinated resin (PF
(A or PTFE) A release layer 171c coated with a paint of 20 to 30 μm is provided (separation type).

Further, as shown in the cross section in FIG. 6B, 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) A paint is mixed and blended, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG. The fixing roller member is formed outside (outer peripheral surface) of 171A. As described above, the heat ray irradiation member 171
g so as to completely absorb the heat ray transmitted through the shaped translucent substrate 171A.
Is set to 90 to 100%, which is approximately 100%, and preferably 95 to 100%. Integrated heat ray absorbing layer 17
The heat ray absorption rate at 1B is lower than about 90%, for example, 2
When it is about 0 to 80%, the heat rays leak, and when the fixing roller member is used for monochrome image formation due to the leaked heat rays, it leaks when black toner adheres to the surface of a specific position of the fixing roller member due to filming or the like. Heat is generated from the adhered portion by the heat rays, and heat is further generated by heat ray absorption at that portion, thereby damaging the integrated heat ray absorbing layer 171B. Further, 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, the heat ray absorptivity of the integrated heat ray absorbing layer 171B, which is approximately 100%, is set so that the heat ray emitted from the heat ray irradiating member 171g and transmitted through the shaped translucent substrate 171A is completely absorbed in the fixing roller member. 100%, preferably 95 to 100%. In addition, local heat generation in the integrated heat ray absorbing layer 171B is also prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the integrated heat ray absorbing layer 171B is 0.1 to 20 μm, preferably 0.3 to 3 μm.
Since the particle size is μm, an agent for adjusting hardness and thermal conductivity is added as a filler. Fine particles of a metal oxide having a diameter of 1 μm or less, preferably 0.1 μm or less, such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate, having a heat ray transmission property (mainly infrared or far infrared ray transmission property). The integrated heat ray absorbing layer 171B may be formed by dispersing 5 to 50% by weight in a resin binder.

According to FIG. 8, the heat ray absorbing layer 171b of the first heat ray fixing roller 17a as the fixing roller member is provided with the above-described concentration distribution of the heat ray absorbing member, thereby generating heat inside the heat ray absorbing layer 171b. Is preferred. 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 shaped translucent substrate 171A which is inscribed is made to have a low concentration, is gradually inclined toward the outer peripheral surface side, and is sequentially increased to be closer to the outer peripheral surface side. (The thickness t of the heat ray absorbing layer 171b is about 2/3 to 4/5 from the shaped translucent substrate 171A side). As a result, the heat generation distribution due to the absorption of heat rays in the heat ray absorbing layer 171b has a maximum value near the center of the heat ray absorbing layer 171b as shown in the graph (b), and the interface and the outer peripheral surface of the heat ray absorbing layer 171b. It is formed in a parabolic shape having a minimum value in the vicinity. Thereby, heat generation due to absorption of heat rays at the interface is reduced, and damage to the adhesive layer and damage to the heat ray absorbing layer 171b at the interface are prevented. In addition, in front of the outer peripheral surface side (with respect to the thickness t of the heat ray absorbing layer 171b,
The concentration distribution from the 1A side to about 2/3 to 4/5) is saturated to the outer peripheral surface. For example, when the integrated heat ray absorbing layer 171B is used, there is no influence even if the outer peripheral surface layer is shaved. To 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. 9, the outer diameter φ of the cylindrical shaped translucent substrate 171A of the first heat ray fixing roller 17a as a fixing roller member is 15 to 60 mm, and the thickness is As t, thicker is better in terms of strength and thinner is better in terms of heat capacity. From the relationship between strength and heat capacity, the difference between the outer diameter φ of the cylindrical shaped translucent substrate 171A and the thickness t is considered. The relationship is 0.05 ≦ t / φ ≦ 0.20, preferably 0.07 ≦ t / φ ≦ 0.14. When the outer diameter φ of the shaped translucent substrate 171A is 40 mm, the thickness t of the shaped translucent substrate 171A is 2 mm ≦ t ≦ 8.
mm, preferably 2.8 mm ≦ t ≦ 5.6 mm. T / φ in the shaped translucent substrate 171A is 0.
If it is less than 05, the strength will be insufficient, and if t / φ exceeds 0.20, the heat capacity will increase and the heating of the first hot-wire fixing roller 17a will be 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 shaped translucent substrate 171A described in FIG. 7 and the fixing device 17 described in FIG. 5, a highly accurate translucent substrate having an outer diameter can be obtained. It is resistant to deformation at the fixing portion (nip portion), does not cause fixing unevenness or fixing wrinkles, enables instantaneous heating, or enables a fixing roller member or a fixing device using a heating wire for quick start fixing with a short heating time. However, particularly when the image forming apparatus is used in the image forming apparatus described with reference to FIG. 1, the toner image can be quickly heated and fixed at the time of single-sided image formation on a frequently used surface, and an energy saving effect can be obtained.

Another example of the fixing device will be described with reference to FIGS. FIG. 10 is an explanatory view showing the structure of a second example of the fixing device, FIG. 11 is an enlarged sectional configuration diagram of the fixing roller member on the upper side of FIG. 10, and FIG.
FIG. 11 is an enlarged cross-sectional configuration diagram of a modified example of the upper fixing roller member of FIG. 10.

As shown in FIG. 10, the fixing device 17A of the second example is a second heat ray fixing device used as an upper (front surface) fixing roller member for fixing a toner image of a front surface image (upper surface side image). A roller 17b and a second fixing roller 47b used as a lower (rear side) fixing roller member for fixing a toner image of a back side image (lower side image). The toner image on the recording paper P is fixed by sandwiching the recording paper P in the nip portion T formed by and applying heat and pressure.

The second heat ray fixing roller 17 used as an upper fixing roller member for fixing the toner image of the front surface image
b is a cylindrical shaped translucent substrate 1 formed by forming a heat-resistant resin layer 171e outside (outer peripheral surface) of the cylindrical translucent substrate 171a described above with reference to FIG. 7 and shaping the heat-resistant resin layer 171e.
71A, an elastic layer 171d outside (outer peripheral surface) of the cylindrical shaped translucent substrate 171A, a heat ray absorbing layer 171b outside the elastic layer 171d (outer peripheral surface), and the heat ray absorbing layer 1
A release roller 171c is provided on the outer side (outer peripheral surface) of the base 71b, and is configured as a soft roller in which a heat ray irradiating member 171g as a heat ray irradiating means using, for example, a halogen lamp or a xenon lamp is provided inside the shaped translucent substrate 171A. Is done. The heat ray emitted from the heat ray irradiating member 171g is the heat ray absorbing layer 1
A fixing roller member that is absorbed by 71b and can be instantaneously heated is formed (second example of the fixing roller member for instantaneous heating).

A second fixing roller 4 used as a lower fixing roller member for fixing the toner image of the back surface image.
7b is formed of a cylindrical metal pipe 472a made of, for example, aluminum, steel, or the like, which is formed by baking or applying a Teflon coat on the outer peripheral surface, and forming a metal pipe 472a.
Is configured as a hard roller having a halogen heater 471c disposed therein. A nip portion T having a convex upper side is formed between the upper soft roller and the lower hard roller, and the toner image is fixed.

TS1 is the upper second heat ray fixing roller 17b
Is a temperature sensor using, for example, a thermistor for performing temperature control, and TS2 is a temperature sensor using, for example, a thermistor for performing temperature control, mounted on the lower second fixing roller 47b.

According to FIG. 11, the second heat ray fixing roller 17
As shown in the cross section in FIG. 11A, the configuration of b is a cylindrical shaped translucent substrate 171 of a cylindrical shaped translucent substrate 171A.
As a, the outer diameter φ is 15 to 60 mm and the thickness t is 2-1.
0 mm, and a ceramic material such as Pyrex glass, sapphire (Al ₂ O ₃ ), or CaF ₂ that transmits heat rays such as infrared rays or far infrared rays from the heat ray irradiation member 171 g;
A light-transmitting resin or the like using polyimide, polyamide, or the like is used. The wavelength of the heat ray passing through the translucent substrate 171a is 0.1 to 20 μm, and preferably 0.3 to 3 μm. Therefore, an adjuster for hardness and thermal conductivity is added as a filler, Of the wavelength, preferably 1 /
Titanium oxide, aluminum oxide, zinc oxide, oxide having an average particle diameter of 1 μm or less, preferably 0.1 μm or less, including primary and secondary particles of 5 or less. The light-transmitting substrate 171a may be formed by dispersing fine particles of a metal oxide such as silicon, magnesium oxide, and calcium carbonate in a resin binder. In the layer φ, the average particle size including primary and secondary particles is 1μ
m or less, preferably 0.1 μm or less is preferable for preventing light scattering and for allowing heat rays to reach the heat ray absorbing layer 171b.

As the heat-resistant resin layer 171e of the cylindrical shaped light-transmitting substrate 171A, a light-transmitting resin or the like using polyimide, polyamide, or the like is used. Thickly applied, the thickness after cutting is 50-1000 μm, preferably 100-500
μm. The wavelength of the heat ray passing through the heat-resistant resin layer 171e is 0.1 to 20 μm, preferably 0.3 to 3 μm.
Since it is μm, an agent for adjusting hardness and thermal conductivity is added as a filler, but the average particle size including primary and secondary particles having a particle size of １ ／, preferably １ ／ or less, of the wavelength of the hot wire Fine particles of a metal oxide having a diameter of 1 μm or less, preferably 0.1 μm or less, such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate, having a heat ray transmission property (mainly infrared or far infrared ray transmission property). A heat-resistant resin layer 171 dispersed in a resin binder
e may be formed. It is preferable that the average particle diameter including the primary and secondary particles is 1 μm or less, preferably 0.1 μm or less, in order to prevent light scattering and allow heat rays to reach the heat ray absorption layer 171b.

The elastic layer 171d is formed of, for example, a rubber layer (base layer) that transmits heat rays (mainly infrared rays or far infrared rays) using silicon rubber having a thickness of 2 to 20 mm, preferably 5 to 15 mm. Is done. Elastic layer 1
As for 71d, in order to cope with high speed, a method of improving the thermal conductivity by mixing a powder of a metal oxide such as silica, alumina or magnesium oxide as a filler with a base rubber (silicone rubber) is adopted. Is 8.4 × 10 ⁻¹
It is preferable to use a rubber layer having a W / (m ° C.) or higher. When the thermal conductivity is increased, the rubber hardness generally tends to increase.
Rubber hardness). Most of the elastic layer 171d of the fixing roller member is occupied by the base layer, and the amount of compression at the time of pressing is determined by the rubber hardness of the base layer. The intermediate layer of the elastic layer 171d is coated with a fluorine-based rubber with 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 elastic layer 171d, HTV (high temperature) is used.
RT with better releasability than e-volcanizing)
V (room temperature volcan)
izing) and LTV (low temperature)
e volcanizing) is coated with a thickness similar to that of the intermediate layer. Further, since the wavelength of the heat ray passing through the elastic layer 171d is 0.1 to 20 μm, preferably 0.3 to 3 μm, as a modifier for hardness and thermal conductivity, the particle diameter is ２ of the wavelength of the heat ray, Preferably, the average particle diameter including primary and secondary particles of 1/5 or less is 1 μm or less, preferably 0.1 μm or less.
Titanium oxide, aluminum oxide, zinc oxide, having a heat ray transmission of less than μm (mainly infrared or far infrared transmission)
The elastic layer 171d may be formed by dispersing fine particles of a metal oxide such as silicon oxide, magnesium oxide, and calcium carbonate in a resin binder. When the average particle diameter including the primary and secondary particles is 1 μm or less, preferably 0.1 μm or less, light scattering is prevented, and the heat rays are supplied to the heat ray absorbing layer 171b.
It is preferable to reach.

The heat ray absorbing layer 171b is formed by forming a heat resistant resin layer 171e on the outer side (peripheral surface) of the light transmitting base 171a and emitting light from the heat ray irradiating member 171g, and shaping the heat resistant resin layer 171e. About 100% of the heat rays transmitted through the elastic substrate 171A and the elastic layer 171d.
Carbon black, graphite, iron black (Fe ₃ O ₄₎ is used for the resin binder so that a heat roller of 0 to 100%, preferably 95 to 100%, is absorbed by the heat ray absorbing layer 171b to form a fixing roller member capable of instantaneously heating. ) And various ferrites and their compounds, copper oxide, cobalt oxide, red iron oxide (Fe
A heat ray absorbing member mixed with powder such as ₂ O ₃ )
The heat ray absorbing member having a thickness of 0 to 200 μm, preferably 20 to 100 μm is formed on the outer side (outer peripheral surface) of the elastic layer 171d by spraying or coating. The heat ray absorption rate in the heat ray absorption layer 171b is lower than about 90%, for example, 20 to 80.
%, The heat rays leak, and when the second heat ray fixing roller 17b as a fixing roller member is used for monochrome image formation due to the leaked heat rays, the second heat ray fixing roller 17b is filmed or the like.
When the black toner adheres to the surface of the heat ray fixing roller 17b at a specific position, heat is generated from the adhering portion due to the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, thereby damaging the heat ray absorbing layer 171b. Further, 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, the heat ray irradiation member 1
The heat ray absorptivity of the heat ray absorbing layer 171b is about 90% to 100%, preferably 95% to 100%, so that the heat rays emitted from 71g and transmitted through the elastic layer 171d are completely absorbed in the second heat ray fixing roller 17b. 100%. When the thickness of the heat ray absorbing layer 171b is less than 10 μm and thin, the heating rate by the absorption of the heat ray in the heat ray absorbing layer 171b is high, but the heat ray absorbing layer 171b by the local heating by the thin film is used.
This may cause breakage or insufficient strength of the heat ray absorbing layer 17b.
If the thickness of 1b exceeds 200 μm, the heat conduction becomes poor, or the heat capacity becomes large, so that instantaneous heating becomes difficult. The heat ray absorption rate of the heat ray absorption layer 171b is approximately 100%
90 to 100%, preferably 95 to 100%, or the thickness of the heat ray absorbing layer 171b is 10 to 200 μm.
m, preferably 20 to 100 μm, local heat generation in the heat ray absorbing layer 171b is prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the heat ray absorbing layer 171b 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 the primary and secondary particles having a particle size of ２, preferably １ ／ or less of the wavelength of the heat ray is included. Fine particles of a metal oxide having a diameter of 1 μm or less, preferably 0.1 μm or less, such as titanium oxide, aluminum oxide, zinc oxide, silicon oxide, magnesium oxide, and calcium carbonate, having a heat ray transmission property (mainly infrared or far infrared ray transmission property). The heat ray absorbing layer 171b may be formed by dispersing 5 to 50% by weight in a resin binder.

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 in order to improve the releasability from the toner. Or fluorinated resin (PF
(A or PTFE) A release layer 171c coated with a paint of 20 to 30 μm is provided (separation type).

Further, as shown in the cross section in FIG.
A heat ray absorbing member mixed with powders such as carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and compounds thereof, copper oxide, cobalt oxide, and red iron (Fe ₂ O ₃ ); a binder and a release agent; Resin (PFA or P
TFE) paint is mixed, and the heat ray absorbing layer 171b and the release layer 171c described above with reference to FIG. The fixing roller member is formed outside (outer peripheral surface) of the elastic layer 171d formed outside (outer peripheral surface) of the base 171A. As described above, 171 g of the heat ray irradiation member
171A and the elastic layer 17
The heat ray absorptivity of the integrated heat ray absorbing layer 171B is about 100% so that the heat ray transmitted through 1d is completely absorbed.
0-100%, preferably 95-100%. When the heat ray absorption rate in the integrated heat ray absorbing layer 171B is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the fixing roller member is used for monochrome image formation due to the leaked heat ray, When the black toner adheres to the surface of the fixing roller member at a specific position due to filming or the like, heat is generated from the adhering portion due to the leaked heat rays, and heat generated by heat ray absorption is further superimposed on that portion, so that the integrated heat ray absorbing layer 171 is formed.
B is damaged. When used for color image formation,
Since the absorption efficiency of the color toner is generally low, and there is a difference in the absorption efficiency between the color toners, fixing failure occurs or fixing unevenness occurs. Accordingly, the heat ray absorption rate of the integrated heat ray absorbing layer 171B is about 100% so that the heat rays emitted from the heat ray irradiating member 171g and transmitted through the shaped translucent substrate 171A are completely absorbed in the fixing roller member.
To 100%, preferably 95 to 100%. Also,
Local heat generation in the integrated heat ray absorbing layer 171B is also prevented, and uniform heat generation is performed. In addition, the integrated heat ray absorbing layer 1
Since the wavelength of the heat ray projected on 71B is 0.1 to 20 μm, 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 transmission properties (mainly infrared or far infrared ray transmission) are dispersed in a resin binder, and are integrated. The heat ray absorbing layer 171B may be formed.

Further, as shown in the cross section in FIG.
A heat ray absorbing member mixed with powders such as carbon black, graphite, iron black (Fe ₃ O ₄ ), various ferrites and compounds thereof, copper oxide, cobalt oxide, and red iron (Fe ₂ O ₃ ); a binder and a release agent; Resin (PFA or P
TFE) paint is further mixed with silicone rubber and blended, and the elastic layer 171d and the integral heat ray absorbing layer 171B described above with reference to FIG. 11B are integrated to form an integral elastic layer 171D also serving as a heat ray absorbing layer. The fixing roller member is formed outside (outer peripheral surface) of the shaped translucent substrate 171A. As described above, the heat ray of the integrated elastic layer 171D also serving as a heat ray absorbing layer is provided so that the heat ray emitted from the heat ray irradiation member 171g and transmitted through the shaped translucent substrate 171A is completely absorbed in the fixing roller member. 90, which is about 100% absorption rate
To 100%, preferably 95 to 100%. When the heat ray absorptivity of the integrated elastic layer 171D is lower than about 90%, for example, about 20 to 80%, the heat ray leaks, and when the fixing roller member is used for monochrome image formation due to the leaked heat ray, If the black toner adheres to the surface of the fixing roller member at a specific position due to, for example, mining, heat is generated from the adhered portion due to the leaked heat rays, and heat generated by absorption of the heat rays is further superimposed on the portion to damage the integrated elastic layer 171D. Further, 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 heat ray irradiation member 171g,
The heat ray absorptivity of the integrated elastic layer 171D is set to about 10 so that the heat ray transmitted through the shaped translucent substrate 171A is completely absorbed.
90% to 100%, preferably 95 to 100%
%. In addition, local heat generation in the integrated elastic layer 171D is also prevented, and uniform heat generation is performed. The wavelength of the heat ray projected on the integrated elastic layer 171D is 0.1 to 20 μm.
m, preferably 0.3 to 3 μm, so that a filler for adjusting the hardness and thermal conductivity is added as a filler, but the particle size is １ ／, preferably １ ／ or less, of the wavelength of the hot wire. 2
The average particle size including the secondary particles is 1 μm or less, preferably 0.1 μm or less.
Fine particles of a 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 (mainly transmission of infrared rays or far infrared rays) are dispersed in a resin binder. The body-shaped elastic layer 171D may be formed.

The second fixing roller member described above
Also in the heat ray absorbing layer 171b, the integrated heat ray absorbing layer 171B and the integrated elastic layer 171D of the heat ray fixing roller 17b,
It is preferable to generate heat inside the heat ray absorbing layer 171b by providing the concentration distribution of the heat ray absorbing member described above with reference to FIG. Thereby, each shaped translucent substrate 1
Reduce the heat generated by the absorption of heat rays at the interface with 71A,
This prevents damage to the adhesive layer at the interface and damage to the heat ray absorbing layer 171b, the integrated heat ray absorbing layer 171B, and the integrated elastic layer 171D. In addition, before the outer peripheral surface side of the integrated heat ray absorbing layer 171B and the integrated elastic layer 171D (the integrated heat ray absorbing layer 171B).
(With respect to the thickness t of the integral elastic layer 171D, about 2/3 to 4/5 from the side of the shaped translucent substrate 171A).
% So as to be saturated so that the integrated heat ray absorbing layer 171B and the integrated elastic layer 17
When 1D is used, there is no effect even if the outer peripheral surface layer is scraped. In the case of the separation type, it is not necessary to form a saturated layer.
Further, the concentration distribution is provided with the inclination, and the heat generation distribution can be adjusted by changing the inclination angle. Further, the relationship between the outer diameter φ and the thickness t of the cylindrical shaped translucent substrate 171A having an outer diameter φ of 15 to 60 mm, as described above with reference to FIG. /Φ≦0.20, preferably 0.07 ≦ t / φ ≦ 0.14. When the outer diameter φ of the shaped translucent substrate 171A is 40 mm, the thickness t of the shaped translucent substrate 171A is 2 mm ≦ t ≦ 8.
mm, preferably 2.8 mm ≦ t ≦ 5.6 mm. T / φ in the shaped translucent substrate 171A is 0.
If it is less than 05, the strength will be insufficient, and if t / φ exceeds 0.20, the heat capacity will increase and the heating of the second heat ray fixing roller 17b will be 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 fixing device 17 described with reference to FIG.
The use of A makes it possible to obtain a highly accurate translucent substrate having an outer diameter, is resistant to deformation at the fixing portion (nip portion), and enables a fixing device for quick start fixing by instantaneous heating. In particular, when the image forming apparatus is used in the image forming apparatus described with reference to FIG. 1, it is possible to instantaneously heat and fix a toner image at the time of single-sided image formation on a frequently used surface, thereby achieving an energy saving effect.

As shown in FIG. 12, as a modification of the upper fixing roller member for fixing the toner image of the surface image, the cylindrical light-transmitting substrate 171a described above with reference to FIG.
A heat-transmissive resin layer 171e is formed on the outer side (outer peripheral surface), and the heat-transmissive resin layer 171e is shaped to form a light-transmitting base 171A.
A heat-absorbing layer 171b, an elastic layer 171d, and a release layer 171c are provided in this order on the outer side (outer peripheral surface) of the shaped translucent base 171A to form an upper fixing roller member. A heat ray irradiation member 17 which is a heat ray irradiation means using, for example, a halogen lamp or a xenon lamp.
It may be configured as a soft roller in which 1 g is disposed. Translucent substrate 171a, heat resistant resin layer 171e, heat ray absorbing layer 1
As for the material, the configuration, and the like of the elastic layer 71b, the elastic layer 171d, and the release layer 171c, the same as those described above with reference to FIG.

A fixing device for double-sided fixing using the fixing roller member for instantaneous heating described with reference to FIG. 10 or FIG. 5 and temperature control thereof will be described with reference to FIG. 13 to FIG. FIG. 13 is a view showing a third example of a fixing device for double-sided fixing using a pair of the instantaneous heating fixing roller member of the first example and the instantaneous heating fixing roller member of the second example. FIG. 14 is a diagram illustrating a fourth example of a fixing device for double-sided fixing using the fixing roller member for instantaneous heating of the second example as a pair, and FIG. 15 is a diagram illustrating a third example or a third example. FIG. 16 is a temperature control timing chart when forming a double-sided image using the fixing device of Example 4; FIG. 16 is a temperature control timing when forming a single-sided image on the front surface using the fixing device of Example 3 or 4; FIG. 17 is a temperature control timing chart at the time of forming a single-sided image on the back surface using the fixing device of the third example or the fourth example.

The fixing device 17 of the third example as an example of a fixing device using a fixing roller member for instantaneous heating for double-sided fixing.
B is a front surface image (image on the upper surface side) as shown in FIG.
First heat ray fixing roller 17a (first example of a fixing roller member for instantaneous heating) similar to that described in FIG. 5 as an upper (front surface) fixing roller member for fixing the toner image of FIG.
A second heat ray fixing roller 17b (fixing for instantaneous heating) similar to that described in FIG. 10 as a lower (rear side) fixing roller member for fixing a toner image of a back side image (lower side image). The recording paper P is sandwiched between nip portions T formed between the upper and lower fixing roller members, and heat and pressure are applied thereto. Fix the toner image.

First heat ray fixing roller 17 used as an upper fixing roller member for fixing a toner image of a front surface image
a is a cylindrical shaped translucent substrate 1 formed by forming a heat-resistant resin layer 171e outside (outer peripheral surface) of the cylindrical translucent substrate 171a described above with reference to FIG. 7 and shaping the heat-resistant resin layer 171e.
A heat ray absorbing layer 171b and a release layer 171c are provided in this order on the outer side (outer peripheral surface) of the cylindrical shaped translucent substrate 171A, and a halogen lamp or a xenon lamp is provided inside the shaped translucent substrate 171A. It is configured as a hard roller provided with a heat ray irradiating member 171g, which is a heat ray irradiating means using the above. The heat ray emitted from the heat ray irradiating member 171g is absorbed by the heat ray absorbing layer 171b to form a fixing roller member capable of instantaneously heating (first example of a fixing roller member for instantaneous heating). The integrated heat ray absorbing layer 171 described above.
A fixing roller member for instantaneous heating using B is also used as the upper fixing roller member.

The second heat ray fixing roller 17 used as a lower fixing roller member for fixing the toner image of the back side image
b is a cylindrical shaped translucent substrate 1 formed by forming a heat-resistant resin layer 171e outside (outer peripheral surface) of the cylindrical translucent substrate 171a described above with reference to FIG. 7 and shaping the heat-resistant resin layer 171e.
71A, an elastic layer 171d, a heat ray absorbing layer 171b, and a release layer 171c are provided in this order on the outer side (outer peripheral surface) of the cylindrical shaped translucent substrate 171A.
A is configured as a soft roller in which a heat ray irradiation member 171g, which is a heat ray irradiation means using a halogen lamp or a xenon lamp, is disposed inside A. Heat ray irradiation member 171g
The emitted heat rays are absorbed by the heat ray absorbing layer 171b to form a fixing roller member capable of instantaneous heating (second example of a fixing roller member for instantaneous heating). The above-mentioned fixing roller member for instantaneous heating using the integrated heat ray absorbing layer 171B and the integrated elastic layer 171D is also used as the lower fixing roller member.

A nip T having a convex lower side is formed between the upper hard roller and the lower soft roller to fix the toner image. TS1 is a temperature sensor mounted on the upper first heat ray fixing roller 17a for performing temperature control, for example, using a thermistor, and TS2 is a lower second heat roller.
It is a temperature sensor using, for example, a thermistor for controlling the temperature attached to the heat ray fixing roller 17b.

Further, as shown in FIG. 14, a fixing device 17C of a fourth example as another example of a fixing device using a fixing roller member for instantaneous heating for double-sided fixing, as shown in FIG. The upper (front side) fixing roller member for fixing the toner image of (1) or the lower (back side) fixing roller member for fixing the back side image (lower side image) of the toner image are both illustrated in FIG. A nip T formed between the upper and lower fixing roller members by using the second heat ray fixing roller 17b (second example of the fixing roller member for instantaneous heating) similar to that described in FIG. The toner image on the recording paper P is fixed by sandwiching the recording paper P and applying heat and pressure.

The second heat ray fixing roller 17b used as an upper fixing roller member for fixing the toner image of the front image or a lower fixing roller member for fixing the toner image of the rear image is the same as that shown in FIG. A cylindrical shaped translucent substrate 171A in which a heat-resistant resin layer 171e is formed on the outside (outer peripheral surface) of the formed cylindrical translucent substrate 171a, and the heat-resistant resin layer 171e is shaped, and the cylindrical shaped translucent substrate 171A. Optical substrate 171
Elastic layer 171d and heat ray absorbing layer 17
1b and a release layer 171c are provided in this order, and inside the shaped translucent substrate 171A, a heat ray irradiating member 171g which is a heat ray irradiating means using, for example, a halogen lamp or a xenon lamp.
Is configured as a soft roller. The heat rays emitted from the heat ray irradiating member 171g are absorbed by the heat ray absorbing layer 171b to form a fixing roller member capable of instantaneous heating (second example of the instantaneous heating fixing roller member). The fixing roller member for instantaneous heating using the integrated heat ray absorbing layer 171B and the integrated elastic layer 171D described above is also used as the upper or lower fixing roller member.

A flat nip portion T is formed between the upper and lower soft rollers to fix the toner image. TS1 is a temperature sensor using, for example, a thermistor for controlling the temperature attached to the upper second heat ray fixing roller 17b. TS2 is for controlling the temperature attached to the lower second heat ray fixing roller 17b. For example, a temperature sensor using a thermistor.

The fixing device 17B shown in FIG. 13 or FIG.
Alternatively, fixing temperature control when applying the fixing device 17C to the image forming apparatus for forming a double-sided image in FIG. 1 will be described below.

As shown in FIG. 15, when forming a two-sided image, the recording sheet P passing through the fixing device 17B or the fixing device 17C in response to the formation of the front and back images by the photosensitive drum 10 has a single-sided image on the front surface. Unlike the continuous printing by forming, the printing is performed intermittently every other sheet. However, the upper fixing roller member for fixing the toner image of the front surface image (in the case of the fixing device 17B, the first heat ray fixing roller 17a and the fixing device 17C). In this case, the second heat ray fixing roller 17b) is heated with the heat ray irradiating member 171g as an upper heat ray irradiating means turned on in synchronization with the passage timing of the recording paper P, so that the fixing temperature set value T during the image forming pause and the image. The temperature of the upper fixing roller member is controlled at an alternate level with the appropriate fixing temperature set value T2 during the formation.

Similarly, the lower fixing roller member (the second heat ray fixing roller 17b in both the fixing device 17B and the fixing device 17C) for fixing the toner image of the back side image is used for recording. The heat ray irradiating member 171g as the heat ray irradiating means is heated in an on state in synchronization with the passage timing of the paper P, and the fixing temperature set value T during the image forming pause and the appropriate fixing temperature set value T2 during the image forming alternate. Temperature control of the lower fixing roller member of the level is performed. At this time, since the double-sided image formation is intermittently performed every other sheet, the non-passing time of the recording paper P is long, so that the temperature control and the temperature can be made uniform and the heat capacity is small. The two-sided image can also be fixed by the fixing roller member.

The temperature control is performed by fixing temperature setting values T, T1, T2 stored in advance in the ROM and temperature sensors TS1, T2.
The detection is performed through the control unit via the comparison circuit by the detection in S2 (see FIG. 4).

In FIG. 15, the temperature control of the upper and lower fixing roller members is performed in an area sandwiching the leading and trailing ends of the recording paper P. If the linear velocity is high, the temperature control timing is set earlier, and further, the printing operation is performed. It is necessary to set T1 and T2 at all times.

As shown in FIG. 16, when forming a single-sided image on the front surface, the recording paper P passing through the fixing device 17B or 17C for forming the image on the front surface by the photosensitive drum 10 is used.
Transport timing is different from continuous printing in double-sided image formation or single-sided backside image formation, and is performed continuously in response to continuous surface image formation by the photosensitive drum 10. The upper fixing roller member (first heat ray fixing roller 17a in the case of the fixing device 17B, second heat ray fixing roller 17b in the case of the fixing device 17C) for fixing the upper heat ray in accordance with the passage timing of the recording paper P. 171 g of the heat ray irradiating member as the irradiating means is on.
The state is heated, and the temperature control of the upper fixing roller member is performed at an alternate level between the fixing temperature set value T during image formation suspension and the appropriate fixing temperature set value T2 during image formation. During copying by single-sided image formation on the front surface, the heating ray irradiating member 171g is turned on and heated before passing the recording paper P, and the upper fixing roller member is heated so as to maintain an appropriate fixing temperature set value T1 during image formation. Temperature control is performed.

On the other hand, the lower fixing roller member (in the case of both the fixing device 17B and the fixing device 17C, the second heat ray fixing roller 17b) controls the heating during the copying by forming a single-sided image on the front surface. Is not performed, or is maintained at the fixing temperature set value T during the suspension of image formation.
Temperature control of the lower fixing roller member is performed.

Temperature control is performed through a control unit via a comparison circuit based on fixing temperature set values T and T1 stored in advance in a ROM and detection by temperature sensors TS1 and TS2 (see FIG. 4).

In FIG. 16, the temperature control of the upper fixing roller member is performed in an area sandwiching the leading and trailing ends of the recording paper P. If the linear velocity is high, the temperature control timing is set earlier, and further, the printing operation is performed. It is necessary to set T1 at all times.

As shown in FIG. 17, when forming a single-sided image on the back side, the conveyance timing of the recording paper P passing through the fixing device 17B or 17C in response to the image formation on the back surface by the intermediate transfer belt 14a is as follows. Unlike the continuous printing by forming the single-sided image on the front side, the printing is performed intermittently every other sheet. However, a lower fixing roller member for fixing the toner image of the rear side image (the fixing device 17C is also used for the fixing device 17B)
In both cases, the second heat ray fixing roller 17b) is heated with the heat ray irradiating member 171g, which is the lower heat ray irradiating means, turned on in synchronization with the passage timing of the recording paper P, so that the fixing temperature setting during image formation suspension is performed. Temperature control of the lower fixing roller member at an alternate level of the value T and the appropriate fixing temperature set value T2 during image formation is performed. During copying by forming a single-sided image on the back surface, the heat ray irradiating member
The heating temperature of the lower fixing roller member is controlled so that 1 g of the fixing roller member is turned on to maintain the fixing temperature set value T2 during image formation.

On the other hand, the upper fixing roller member
During the copying by the one-sided image formation on the back surface, the heating control is not performed, or the temperature of the lower fixing roller member is controlled so as to maintain the fixing temperature set value T during the pause of the image formation.

As shown by the dashed line in FIG. 17, the upper fixing roller member turns on the heat ray irradiating member 171g before passing the recording paper P during copying by the single-sided image formation on the back surface.
More preferably, heating is performed so as to maintain an appropriate fixing temperature set value T1 during image formation as a state, and the upper fixing roller member is turned on to heat the nip portion T.
Is heated so that the toner image is not disturbed when the leading edge of the recording paper P is added to the nip portion, and the fixing of the toner image of the single-sided image only on the back surface is performed satisfactorily.

The temperature control is performed by setting the fixing temperature set values T, T2, (T1) stored in advance in the ROM and the temperature sensor TS.
1, through the control unit via the comparison circuit by the detection by TS2 (see FIG. 4).

In FIG. 17, the temperature control of the lower fixing roller member and the upper fixing roller member is performed in a region sandwiching the front and rear ends of the recording paper P. However, if the linear velocity is high, the temperature control timing is advanced. It is necessary to set T1 and T2 at all times during the printing operation.

According to FIGS. 15 to 17 described above, when forming a single-sided image on the front surface, forming a single-sided image on the back surface, or forming a double-sided image, the fixing of the toner image has a small heat capacity and is capable of quick start. The fixing is performed by the fixing roller member, so that good fixing is performed without providing a warm-up time. In particular, since the image formation on both sides and the image formation on the back side of only one side are performed intermittently every other sheet, the fixing of the toner image on the back side can be performed by the lower fixing roller member having a smaller heat capacity than the conventional heat fixing roller. The heat capacity is sufficient, and the fixing of the back surface image by the lower fixing roller member becomes possible.

Note that the image forming apparatus is set so that temperature control is automatically performed in the double-sided image forming state at the time of the initial operation when the power switch is turned on, or when the mode is changed from the pause mode to the print operation mode. Further, it is also possible to control so that the heating control of the upper and lower fixing roller members is turned off when the unused time elapses a predetermined time.

With the configuration described above, different energy consumption is performed when forming a single-sided image only on the front surface, when forming a single-sided image only on the back surface, or when forming a double-sided image.
Compared to conventional fixing devices that use heating elements for the upper and lower rollers, proper energy consumption is performed during single-sided image formation and double-sided image formation, respectively, so that both consume less energy, and the conventional upper and lower rollers generate heat. Compared to a fixing device using a body or a film fixing device using a ceramic heater, a fixing device that has a wider nip width in the fixing area and higher fixing performance, and that can perform double-sided fixing with low heat capacity and zero warm-up time is available. Provided.

As described above, by using the fixing device 17B or the fixing device 17C described with reference to FIG. 13 or FIG. A quick start by heating makes it possible to use a fixing roller member and a fixing device for fixing, but as described above, particularly by using the image forming apparatus described with reference to FIG. Instantaneous heating and fixing, and an energy saving effect can be obtained.

[0114]

According to the first to third aspects of the present invention, a fixing roller using a heat ray for quick start fixing that can be instantaneously heated or has a short heating time by obtaining a highly accurate translucent substrate having an outer diameter. A member is provided.

According to the fourth to sixth aspects, by obtaining a highly accurate translucent substrate having an outer diameter, it is possible to achieve instantaneous heating or a quick heating time without causing fixing unevenness or fixing wrinkles. Is provided.

[Brief description of the drawings]

FIG. 1 is a sectional view of a color image forming apparatus showing an embodiment of an image forming apparatus using a fixing device 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 diagram illustrating an example of a document image reading unit.

FIG. 4 is a block diagram of a control circuit of the image forming apparatus.

FIG. 5 is an explanatory diagram illustrating a structure of a first example of a fixing device.

FIG. 6 is an enlarged cross-sectional configuration diagram of the upper fixing roller member of FIG. 5;

FIG. 7 is a perspective view showing shaping of a light-transmitting substrate.

FIG. 8 is a diagram illustrating a density distribution of a heat ray absorbing layer of a fixing roller member.

FIG. 9 is a diagram illustrating an outer diameter and a thickness of a translucent substrate of a fixing roller member.

FIG. 10 is an explanatory diagram illustrating a structure of a second example of the fixing device.

11 is an enlarged cross-sectional configuration diagram of the upper fixing roller member of FIG. 10;

FIG. 12 is an enlarged cross-sectional configuration diagram of a modified example of the upper fixing roller member of FIG.

FIG. 13 is a diagram showing a third example of a fixing device for double-sided fixing using the fixing roller member for instantaneous heating of the first example and the fixing roller member for instantaneous heating of the second example as a pair; is there.

FIG. 14 is a diagram showing a fourth example of a fixing device for double-sided fixing using a pair of instantaneous heating fixing roller members of the second example.

FIG. 15 is a temperature control timing chart during double-sided image formation using the fixing device of the third example or the fourth example.

FIG. 16 is a temperature control timing chart when a single-sided image is formed on the front surface using the fixing device of the third example or the fourth example.

FIG. 17 is a temperature control timing chart when a single-sided image is formed on the back surface using the fixing device of the third example or the fourth example.

DESCRIPTION OF SYMBOLS 10 Photoreceptor drum 11 Scorotron charger 12 Exposure optical system 13 Developing device 14a Intermediate transfer belt 14c Transfer device 14g Back transfer device 17, 17A, 17B, 17C Fixing device 17a First heat ray fixing roller 17b Second heat ray Fixing roller 171A Shaped translucent substrate 171a Translucent substrate 171B Integrated heat ray absorbing layer 171b Heat ray absorbing layer 171c Release layer 171D Integrated elastic layer 171d Elastic layer 171g Heat ray irradiating member P Recording paper

Continued on the front page (72) Kuki Nagase, Inventor Konica Co., Ltd. 2970 Ishikawacho, Hachioji-shi, Tokyo

Claims (6)

[Claims] 1. A fixing roller member for fixing a toner image on a transfer material to the transfer material by applying heat and pressure, comprising: a cylindrical light-transmitting substrate having a light-transmitting property with respect to heat rays; Forming a heat-resistant resin layer on the outside of the heat-resistant substrate, shaping the heat-resistant resin layer to form a shaped light-transmitting substrate, and then absorbing outside the shaped light-transmitting substrate about 100% of the heat rays. A fixing roller member provided with an absorbing layer. 2. The fixing roller member according to claim 1, wherein a light transmitting elastic layer is provided between the shaped light transmitting substrate and the heat ray absorbing layer. 3. The fixing roller member according to claim 1, wherein an elastic layer is provided outside the heat ray absorbing layer. 4. A fixing device for fixing a toner image on a transfer material to said transfer material by heating and pressurizing, wherein a heat ray irradiating means for emitting a heat ray is disposed inside, and has a light transmitting property with respect to said heat ray. After providing a cylindrical light-transmitting substrate, forming a heat-resistant resin layer outside the light-transmitting substrate, shaping the heat-resistant resin layer into a shaped light-transmitting substrate, and then forming the shaped light-transmitting substrate. A fixing device provided with a heat ray absorbing layer outside of the fixing device. 5. The fixing device according to claim 4, wherein a light-transmitting elastic layer is provided between the shaped light-transmitting substrate and the heat ray absorbing layer. 6. The fixing device according to claim 4, wherein an elastic layer is provided outside the heat ray absorbing layer.