JP3430804B2 - Toner image transfer fixing method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner image transfer / fixing method for transferring and fixing a toner image on an intermediate transfer member to a recording medium, and a toner image transfer / fixing apparatus suitable for carrying out the method.

[0002]

2. Description of the Related Art Conventionally, in electrophotographic copying machines, printers, facsimiles, etc., a toner image is transferred from a toner image bearing member carrying a toner image to an intermediate transfer member, and the toner image on the intermediate transfer member is used as a recording medium. A toner image transfer-fixing method for transferring and fixing the toner onto a sheet is widely known. For example, Japanese Patent Publication 64
No. 1024 and Japanese Patent Publication No. 64-1027 disclose a heating roll and a pressure roll including an intermediate transfer member and a recording medium, which are superposed with a toner image transferred on an endless belt-shaped intermediate transfer member sandwiched therebetween. There is disclosed a method in which the toner image on the intermediate transfer member is transferred and fixed on a recording medium by press contacting with. In this method, since the pressure roller arranged on the back surface side of the recording medium is not provided with the heating means, the recording medium absorbs a large amount of heat, and the fluidity of the toner on the side in contact with the recording medium is lowered. There is a problem that fixing failure is likely to occur during high-speed recording.

Further, Japanese Patent Publication No. 57-20632, Japanese Patent Publication No. 58-36341 and Japanese Patent Publication No. 64-1023.
In the publication, a toner image transferred onto an endless belt-shaped intermediate transfer member is heated to a temperature equal to or higher than a melting point of the toner, and then the intermediate transfer member and a recording medium are pressed to record the toner image on the intermediate transfer member. In transferring and fixing the image on the medium, the intermediate transfer body and the recording medium are brought into pressure contact with each other, and then the moving intermediate transfer body and the recording medium are brought into contact with each other for a long time, and the intermediate transfer body performs recording during this long contact. A method is disclosed in which the heat transfer to the medium is sufficiently performed to improve the fixing failure due to the decrease in the fluidity of the toner in contact with the recording medium. However, in this method, while the intermediate transfer body and the recording medium are moving while being in contact with each other for a long time, the intermediate transfer body and the recording medium are misaligned with each other, and an image shift occurs, or the intermediate transfer body and the recording medium are recorded. There is a problem in that the pressure applied to the medium becomes non-uniform and image distortion easily occurs.

In addition to these, Japanese Patent Publication No. 3-63756, Japanese Patent Publication No. 3-63757, and Japanese Patent Publication No. 3-6.
Japanese Patent No. 3758 discloses a device for sandwiching an intermediate transfer member carrying a toner image and a recording medium by a pair of heating and pressing rolls to transfer and fix the toner image on the intermediate transfer member onto the recording medium. There is disclosed a toner image transfer and fixing method in which a heater for preheating a recording medium is provided on the upstream side of the transfer and fixing area in addition to the above heating and pressing roll to enable high speed fixing.

Among these three preheating type toner image transfer and fixing methods, the method disclosed in Japanese Patent Publication No. 3-63756 discloses a method in which an intermediate transfer member is stretched between a pair of heating and pressing rolls. The first heating / pressurizing roll is heated to a temperature lower than the toner melting temperature, is disposed so as to face the first heating / pressurizing roll, and cooperates with the first heating / pressurizing roll to sandwich the intermediate transfer member. The second heating / pressurizing roll for pressing is heated to a temperature above the melting temperature of the toner, and the heater for preheating is configured to heat the recording medium to a temperature above the melting temperature of the toner.

Further, the method disclosed in Japanese Patent Publication No. 3-63757 differs from the method disclosed in Japanese Patent Publication No. 3-63756 in that the second heating and pressing roll is heated to a temperature lower than the toner melting temperature. Is configured. The first
The heating temperature of the heating / pressurizing roll and the heater for preheating is the same as the method disclosed in Japanese Patent Publication No. 3-63756.

Further, the method disclosed in Japanese Patent Publication No. 3-63758 differs from the method disclosed in Japanese Patent Publication No. 3-63756 in that the preheating heater heats the recording medium to a temperature lower than the toner melting temperature. Is configured. The heating temperature of the first heating / pressurizing roll and the second heating / pressurizing roll is the same as the method disclosed in Japanese Patent Publication No. 3-63756.

According to the preheating type transfer fixing method disclosed in these three publications, excessive heating of the heating / pressurizing roll is suppressed, thermal efficiency is improved, and excessive heating is caused. There is an advantage that the occurrence of fixing failure due to an offset phenomenon or the like is prevented.

[0009]

However, when an image is recorded on both sides of the recording medium by these preheating type transfer fixing methods, at the time of recording an image on the second side after recording the image on the first side. The image on the first surface may be remelted and the image quality may be deteriorated. That is, in the methods disclosed in Japanese Patent Publication No. 3-63756 and Japanese Patent Publication No. 3-63758, the second heating and pressing roll is heated to the toner melting temperature or higher, so during image recording on the second surface. , The image on the first surface is heated to a temperature equal to or higher than the toner melting temperature by the second heating / pressurizing roll and remelted. Further, in the method disclosed in Japanese Patent Publication No. 3-63757, at the time of image recording on the second surface, the recording medium is heated to a temperature higher than the toner melting temperature by the preheating heater and the back surface (first surface) of the recording medium. The image of is also heated via the recording medium. Therefore, in view of the temperature distribution in the thickness direction of the image, the temperature of the portion of the image on the first surface in contact with the recording medium may be heated to the toner melting temperature or higher and remelted. Therefore, any of these three transfer fixing methods based on the preheating method may deteriorate the image quality when image recording is performed on both surfaces of the recording medium. Further, when the recording medium is preheated before transfer fixing as in these methods, when a recording medium such as paper is used, the paper may be corrugated due to heat and a jam may occur at the heating and pressing roll nip portion. In addition, since the moisture contained in the paper is vaporized in the stage of this preheating, there is a problem that the thermal efficiency is lowered.

In view of the above circumstances, it is an object of the present invention to provide a toner image transfer and fixing method and apparatus capable of high-speed and high-quality double-sided recording.

[0011]

A toner image transfer and fixing method of the present invention that achieves the above object sandwiches a toner image on an intermediate transfer member between a toner image-transferred intermediate transfer member and a predetermined recording medium. And the intermediate transfer body and the recording medium in the superposed state are sandwiched by a first pressing body that is in contact with the intermediate transfer body and a second pressing body that is in contact with the recording medium, which are heated respectively. In the toner image transfer fixing method of transferring and fixing the toner image on the intermediate transfer member to the recording medium by the above, the intermediate transfer member is transferred to the intermediate transfer member, and then the toner image is transferred onto the recording medium. Preliminary predetermined heating before being sandwiched between the first and second pressing bodies
Preheat using a heat source for the intermediate transfer member in the preheated state, and the recording medium superposed on the intermediate transfer member,
In different heat source and the preheating heat source, and the first pressing body that is heated to above the melting temperature of the toner forming the toner image, with a different heat source and the preheating heat source, is heated to below the melting temperature It is characterized in that it is sandwiched by the second pressing body.

Further, the toner image transfer and fixing device of the present invention which achieves the above-mentioned object receives the transfer of the toner image at the predetermined first transfer position while cyclically moving, and transfers the transferred toner image to the predetermined second transfer position. A recording medium that conveys an intermediate transfer member and a predetermined recording medium that are conveyed to the transfer position to the second transfer position, and superimposes the recording medium on the intermediate transfer member with the toner image on the intermediate transfer member interposed therebetween. Transporting means, and the second
A first pressing body in contact with the intermediate transfer body and a second pressing body in contact with the recording medium, which sandwiches the intermediate transfer body and the recording medium, which are superposed at the transfer position, with a toner image. A first pressing body heating means for heating to above the melting temperature of the toner forming the toner, and a second heating means for heating the second pressing body below the melting temperature of the toner forming the toner image.
Pressing means heating means and the first pressing means heating means and the second heating means for preheating the intermediate transfer body at a preheating position between the first transfer position and the second transfer position .
And a pre-heating means provided separately from the pressing body heating means, and a transfer fixing means for transferring and fixing the toner image on the intermediate transfer body onto the recording medium. And

[0013] Here, the first及 beauty second pressing body, the first and second pressing prior to the transfer-fixing operation of fixing with the toner image on the intermediate transfer member is transferred onto the recording medium The intermediate transfer body may be sandwiched between the bodies, and a pressing body moving mechanism may be provided to separate the first and second pressing bodies from each other after the transfer fixing operation is completed. In addition, the above
The heating means is a first pusher with respect to the moving direction of the intermediate transfer member.
The intermediate transfer body and the recording medium are sandwiched between the pressure body and the second pressure body.
Preliminary addition of intermediate transfer on the upstream side of the second transfer position
It is heated, and the preheating means is an intermediate transfer.
Regarding the moving direction of the body, the first pressing body and the second pressing body
Is wider than the nip width between the intermediate transfer body and the recording medium.
It is intended to preheat the intermediate transfer member over the area.
And are preferred. In this case, the preheating means is
It may be a cone rubber heater.

The toner melting temperature in the present invention is defined as follows. That is, while using a commercially available flow tester to heat 1.5 g of the toner molded by a pressure molding machine at a temperature rising rate of 5 ° C./minute from a temperature of 60 ° C. to 150 ° C. in steps of 3 ° C., Apparent viscosity η'by measuring the toner outflow amount when extruded from a nozzle having a load of 98 N (10 kgf), a nozzle diameter of 0.5 mm and a nozzle length of 1 mm.
(Poise), the apparent viscosity η'is 10 ⁴ p
The temperature at which the toner is turned on is defined as the toner melting temperature.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. Figure 1 is a schematic diagram of one <br/> embodiment of the transfer of the toner image fixing device of the present invention. The toner image transfer / fixing apparatus 100 shown in FIG. 1 includes an endless belt-shaped intermediate transfer member 1 that circulates in the direction of arrow A, belt stretching rolls 8a, 8b, 8c, and 8d that stretch the intermediate transfer member 1. Second recording medium 9a
To the transfer position P2 of the intermediate transfer body 1 and the recording medium conveying means 9 for superposing on the intermediate transfer body 1, and the toner image 2 on the intermediate transfer body 1.
A transfer fixing unit 10 is provided for transferring and fixing the toner onto the recording medium 9a.

The intermediate transfer member 1 receives the toner image 2 transferred at the first transfer position P1 and conveys the transferred toner image 2 to the second transfer position P2. The transfer of the toner image at the first transfer position P1 can be performed by known methods such as electrostatic force, pressure, and adhesive force. Intermediate transfer body 1
The toner image 2 transferred onto the toner image may be either a single color toner image or a multicolor multiple toner image. As the intermediate transfer member 1,
100 μm on a 75 μm thick polyimide resin sheet
A laminated sheet coated with a room temperature curable silicone resin having a thickness of 5 is used. The intermediate transfer member 1 is not limited to the double structure as described above, and may have any structure such as a single layer structure or a three layer structure or more. Further, the constituent material of the intermediate transfer body 1 is also a material suitable for receiving the toner image transfer from the toner image carrier on which the toner image 2 is formed and carried, and which can withstand transfer fixing of the toner image 2 to the recording medium 9a. Any material may be used as long as it is.

Although the endless belt-shaped intermediate transfer member is used in this embodiment, a roll-shaped intermediate transfer member may be used. In that case, the restrictions on materials and composition are
This is similar to the case of the endless belt-shaped intermediate transfer member. The recording medium conveying means 9 conveys the recording medium 9a to the second transfer position P2, and transfers the recording medium 9a to the toner image 2 on the intermediate transfer body 1.
It has a function of superposing it on the intermediate transfer body 1 by sandwiching it.

The transfer / fixing means 10 comprises a silicone rubber heater 3 as a preheating means, pressing rolls 4 and 5 as first and second pressing bodies, and a halogen lamp as first and second pressing body heating means. It consists of 6,7. The silicone rubber heater 3 is attached and configured on a curved aluminum plate, and the back surface side of the intermediate transfer body 1 at the preheating position P3 spread between the first transfer position P1 and the second transfer position P2. Have been deployed to. The silicone rubber heater 3 is provided with an intermediate transfer member 1 and a toner image 2 on the intermediate transfer member 1.
And are preheated above the toner melting temperature. By thus performing the preheating over a wide area, the intermediate transfer member 1 can be circulated and moved at a high speed, and a high-speed toner forming / transfer fixing device can be realized.

The preheating means is not limited to the silicone rubber heater, but any means can be used as long as it can preheat the intermediate transfer body 1 and the toner image 2 on the intermediate transfer body 1 to a temperature above the toner melting temperature. It may have such a configuration. Even if the heat source of the preheating means is composed of a single heat source,
Alternatively, a plurality of heat sources may be combined. The disposition position of the preheating means is not limited to the back surface side of the intermediate transfer body 1, and may be the front surface side of the intermediate transfer body 1. Further, the preheating means may be configured by incorporating a self-heating element inside the intermediate transfer member. When the method of heating from the surface side of the intermediate transfer body 1 is adopted, a non-contact heating method, for example, a heating method utilizing radiant heat is desirable in order to prevent the toner image 2 from being disturbed by the preheating means. Further, when the toner image is a color toner image composed of a plurality of colors, it is desirable to adopt a heating method using far infrared rays so as to prevent uneven heating due to the difference in the light absorption characteristics of the respective color toners. The heating time by the preheating means is the same as that of the intermediate transfer member 1.
The toner image 2 on the intermediate transfer member 1 and the toner image 2 on the intermediate transfer member 1 may be heated for a time sufficient to be equal to or higher than the toner melting temperature.
For multiple color images where the thickness of
In order to prevent uneven melting of the toner, it is necessary to secure a sufficient heating time so that the temperature distributions in the thickness direction of the intermediate transfer body 1 and the toner image 2 become uniform. The heating time varies depending on the material of the toner, the material and thickness of the intermediate transfer member, and the heating means, but specifically, it is preferably 0.3 seconds or more.

First pressing roll 4 in contact with the intermediate transfer member 1.
And the second pressing roll 5 contacting the recording medium 9a is
The intermediate transfer body 1 and the recording medium 9a which are superposed at the transfer position P2 are clamped. As the first and second pressing rolls 4 and 5, rolls obtained by coating a heat-curable silicone rubber on an aluminum cored bar are used. In addition,
The materials of the first and second pressing rolls 4 and 5 may be any materials as long as they can withstand the pressure and heat in the transfer fixing step. Further, the configuration of the first and second pressing bodies is not limited to the configuration of the first and second pressing rolls 4 and 5 as described above, and the configuration of the intermediate transfer body 1 and the recording medium 9a is not limited. Any structure may be used as long as it can uniformly press the intermediate transfer body 1 and the recording medium 9a without causing floating or displacement. For example, one pressing roll and one fixed pad may be combined, or a set of fixed pads may be used.

A halogen lamp 6 is provided inside the first pressing roll 4 as a first pressing body heating means, and heats the first pressing roll 4 to a temperature above the melting temperature of the toner. In addition, a halogen lamp 7 is provided inside the second pressing roll 5 as a second pressing body heating means, and heats the second pressing roll 5 to a temperature below the melting temperature of the toner. Therefore, at the second transfer position, the intermediate transfer member 1
Surface of the intermediate transfer member 1 on which the toner image 2 is not transferred is heated and pressed by the pressing roll 4 heated to a temperature equal to or higher than the melting temperature of the toner. Is heated and pressed by the pressing roll 5 heated to a temperature lower than the melting temperature of the toner.

In this way, the toner image 2 on the intermediate transfer member 1 is
The surface of the recording medium 9a on which the toner image 2 is not transferred and the surface of the recording medium 9a on which the toner image 2 is transferred are heated to different temperatures. In the case of performing image recording on the first surface, when the image is recorded on the second surface after the image is recorded on the first surface, the heating temperature of the first surface is suppressed to a temperature lower than the melting temperature of the toner, and the image on the first surface is regenerated. Image quality deterioration due to melting can be prevented.

The time during which the intermediate transfer member and the recording medium are heated and pressed by the first and second pressing rolls 4 and 5 is set to such a time that sufficient fixing strength can be obtained after transfer and fixing. In particular, in the case of a color image, the time is set within a range in which the color development is sufficient and the image quality of the first image is not deteriorated during the second image recording of the double-sided recording due to the heat conduction from the pressing body on the intermediate transfer body side. Specifically, it is preferably 0.02 seconds or more and 0.1 seconds or less, though it varies depending on the toner material, the material of the intermediate transfer member, the thickness, the heating temperature of the pressing body heating means, and the like.

In this embodiment, the halogen lamps 6 and 7 are used as the first and second pressing body heating means, but the first and second pressing body heating means are limited to the halogen lamps. However, other well-known heating means can be used. By the way, in the schematic view of the first embodiment shown in FIG. 1, the first and second pressing rolls 4 and 5 are shown.
However, the intermediate transfer member 1 and the recording medium 9a are always sandwiched between them, and they are in a transfer fixing state in which they are pressed against each other. It is preferable to provide a pressing body standby mechanism capable of switching between a transfer fixing state in which the intermediate transfer body 1 and the recording medium 9a are sandwiched and a standby state in which the pressing rolls 4 and 5 are separated from each other. By doing so, the pressure rolls 4 and 5 can be separated from each other except during the transfer fixing operation, and the surface temperature of the pressure rolls 4 and 5 can be maintained at a temperature suitable for each. 1, the recording medium 9a, and the toner image 2 can be maintained at appropriate temperatures.

Next, the toner image transfer / fixing device 100 described above.
A method of transferring and fixing the toner image on the intermediate transfer member onto the recording medium by using will be described with reference to FIG. A yellow toner image is formed on a photoconductor (not shown) by the well-known electrophotographic charging, exposing, and developing processes, and the yellow toner image formed on the photoconductor is circulated and moved through the intermediate transfer body 1. Upper first transfer position P1
In, the image is transferred onto the intermediate transfer member 1. Subsequently, formation of toner images of magenta and cyan on the photoconductor and the intermediate transfer body 1
The toner images 2 of three colors of yellow, magenta, and cyan are formed on the intermediate transfer body 1 in sequence. The intermediate transfer body 1 on which the toner image 2 has been transferred is circulated and moved, and when the intermediate transfer body 1 reaches the preliminary heating position P3 before being sandwiched between the first and second pressing rolls 4 and 5, the preliminary heating is performed. The intermediate transfer body 1 is preheated by the silicone rubber heater 3 provided at the position P3. Preheated intermediate transfer member 1
Are further circulated, and the toner image 2 on the intermediate transfer member 1 arrives at the second transfer position P2 in accordance with the timing.
The recording medium 9a is supplied to the second transfer position P2 by the recording medium conveying means 9 for superposing the recording medium 9a on the intermediate transfer body 1. The first pressure roll 4 and the second pressure roll 5, which are arranged opposite to the second transfer position P2, transfer the intermediate transfer body 1 on which the toner image 2 is transferred and the recording medium 9a onto the intermediate transfer body 1. The toner image 2 is pinched with the toner image 2 sandwiched therebetween. The surface temperature of the first pressing roll 4 is heated to the melting temperature of the toner or higher by the halogen lamp 6 provided inside the first pressing roll 4, and the surface temperature of the second pressing roll 5 is the second temperature. The toner is heated below the melting temperature of the toner by the halogen lamp 7 provided inside the pressing roll 5. The first and second pressing rolls 4 and 5 heat and pressurize the intermediate transfer body 1 on which the toner image 2 is transferred and the recording medium 9a, so that the toner image 2 on the intermediate transfer body 1 is recorded on the recording medium 9a.
It is transferred and fixed at the same time. The second pressing roll 5 is heated to a temperature below the toner melting temperature by the halogen lamp 7 provided inside the second pressing roll 5, but in order to increase the recording speed, the heating temperature should be as high as the toner temperature. It is desirable to be close to the melting temperature. Specifically, it is lower than the toner melting temperature, and the [toner melting temperature-4
0 ° C.] or higher is desirable.

[0026]

[0027]

EXAMPLES Next, examples of the present invention will be described. (Embodiment 1) The following embodiment shows a result of a test conducted by using the toner image transfer / fixing apparatus 100 shown in FIG.

A three-color toner image of yellow, magenta, and cyan is formed on a photoreceptor (not shown) by an electrophotographic charging, exposing, and developing process, and the toner images are formed.
Electrostatic transfer was performed on the intermediate transfer member 1 of the toner image transfer fixing device 100. A toner having a melting temperature of 115 ° C. was used. The intermediate transfer member 1 has a moving speed of 160 mm / s and is indicated by an arrow A.
It was circularly moved in the direction. At the preheating position P3, a silicone rubber heater 3 having a length of 80 mm in the belt moving direction and controlled to a temperature of 170 ° C. is provided.
The silicone rubber heater 3 preheats the intermediate transfer member 1 and the toner image 2. The temperature of the toner image 2 on the intermediate transfer member 1 at the end portion of the preheating position P3 was measured by an infrared radiation thermometer and was about 125 ° C. When the intermediate transfer body 1 carrying the toner image 2 reaches the second transfer position P2, the recording medium conveying means 9 is placed on the intermediate transfer body 1.
The recording medium 9a having a thickness of 100 μm supplied by the above is overlapped, and the intermediate transfer body 1 and the recording medium 9a are heated and pressed by the first and second pressing rolls 4 and 5, and the toner image 2 on the intermediate transfer body 1 is recorded. It was transferred and fixed onto the medium 9a. The halogen lamp 6 arranged inside the first pressing roll 4 controls the surface temperature of the first pressing roll 4 to be heated to 170 ° C., and the halogen lamp 7 arranged inside the second pressing roll 5 is The surface temperature of the second pressing roll 5 was controlled to be heated to 100 ° C. The nip width when pressed by the first and second pressing rolls 4 and 5 was 6 mm at the roll center.
It should be noted that prior to transfer fixing, the first and second pressing rolls 4,
The surface of 5 was wiped with a cloth dipped in n-hexane to remove oil and fat. This is to prevent the oil and fat from the pressing rolls 4 and 5 from adhering to the surface of the intermediate transfer member 1 and transferring to the photosensitive member, and developing the toner on the photosensitive member to increase the background density. . After the transfer and fixing, the intermediate transfer body 1 and the recording medium 9a were allowed to cool to a temperature of 50 ° C. or less, and then the recording medium 9a was peeled from the intermediate transfer body 1. The image transferred and fixed on the recording medium 9a in this way had good fixing strength and good color development.

For comparison, the temperature of the toner image 2 on the intermediate transfer member 1 at the end of the preheating position P3 is lowered to 105 ° C. by lowering the set temperature of the silicone rubber heater 3 to 150 ° C. As a result of a transfer fixing test, a fixing failure occurred. (Second Embodiment) Next, a second embodiment will be described. Example 2 is an example in which a recording medium having a transfer-fixed image formed on one side of the recording medium is used as a recording medium, and an image is formed on the back side of the recording medium to perform double-sided recording. The conditions other than the recording medium are the same as those in the first embodiment. The images obtained as a result of double-sided recording were good in both fixing strength and color development on both sides. For comparison, a similar experiment was conducted by setting the heating temperature of the second pressing roll 5 to 140 ° C., and the image formed first was melted by the heating by the second pressing roll 5. However, deterioration of image quality was observed.

[0030]

[0031]

As described above, according to the toner image transfer fixing method and apparatus of the present invention, the intermediate transfer member and the toner image on the intermediate transfer member are preliminarily heated to the melting temperature of the toner or higher before transfer fixing. By providing the heating means, the toner image can be sufficiently heated and melted, and the preheated toner image is heated to the melting temperature of the toner or higher.
And the second pressing body heated to a temperature lower than the melting temperature of the toner, so that the image quality of the backside image is prevented from deteriorating, and high-speed, high-quality double-sided recording is possible. A fixing method and device can be realized.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a first embodiment of a toner image transfer fixing device of the present invention.

[Explanation of symbols]

1 Intermediate Transfer Body 2 Toner Image 3 Silicone Rubber Heater (Preliminary Heating Means) 4,5 Pressing Rolls 6, 7 Halogen Lamps 8a, 8b, 8c, 8d Belt Tension Roll 9 Recording Medium Conveying Means 9a Recording Medium 10 Transfer Fixing Means 100 toner image transfer fixing device

Front page continued (72) Inventor Tatsuo Okuno 430 Nakai-cho, Ashigaragami-gun, Kanagawa Green Tech Nakakai Fuji Xerox Co., Ltd. (72) Inventor Takayuki Yamashita, 430 Nakai-cho, Ashigagami-gun, Kanagawa Fuji Xerox Co., Ltd. (56 ) Reference JP 59-124350 (JP, A) JP 3-51872 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 15/16 101 G03G 15/20 102

Claims (6)

(57) [Claims] 1. An intermediate transfer body to which a toner image is transferred and a predetermined recording medium are superposed with the toner image on the intermediate transfer body being sandwiched therebetween, and the intermediate transfer body and the recording medium in a superposed state, The toner image on the intermediate transfer body is transferred onto the recording medium by being sandwiched by a first pressing body that is in contact with the intermediate transfer body and a second pressing body that is in contact with the recording medium, each of which is heated. In the method of transferring and fixing a toner image, the intermediate transfer member is subjected to a predetermined preliminary step at a stage after the toner image is transferred to the intermediate transfer member and before being sandwiched by the first and second pressing members. A preheating is performed using a heating heat source, and the preheated intermediate transfer member and the recording medium superposed on the intermediate transfer member are different from the preheating heat source.
In becomes a heat source, wherein the first pressing member, the preheating heat source which is heated above the melting temperature of the toner forming the toner image
A method for transferring and fixing a toner image, characterized in that it is sandwiched between the second pressing body heated below the melting temperature by a heat source different from the above. 2. An intermediate transfer member that receives a toner image transferred at a predetermined first transfer position while being circulated and conveys the transferred toner image to a predetermined second transfer position, and a predetermined recording medium as the first transfer medium. A recording medium conveying unit that conveys the recording medium to the second transfer position and superimposes the recording medium on the intermediate transfer body with the toner image on the intermediate transfer body interposed therebetween, and at the second transfer position. A first pressing body that is in contact with the intermediate transfer body and a second pressing body that is in contact with the recording medium sandwiching the intermediate transfer body and the recording medium, and the first pressing body are used for forming a toner image. First pressing body heating means for heating to a melting temperature or higher, second pressing body heating means for heating the second pressing body to a temperature lower than the melting temperature of toner forming a toner image, and the first transfer body. Between the position and the second transfer position. Preheating said intermediate transfer member in the heating position, the first pressing member heated hand
Provided separately from both the step and the second pressing body heating means.
And a pre-heating means for transferring the toner image on the intermediate transfer member to the recording medium and fixing the toner image on the recording medium. 3. The first and second pressing bodies are the intermediate
While transferring the toner image on the transfer body onto the recording medium,
Prior to the transfer fixing operation for fixing, the first and second pressing
The intermediate transfer body is sandwiched by the body, and the transfer fixing operation is completed.
Later, the pressing for separating the first and second pressing bodies from each other
The toner image transfer / fixing device according to claim 2, further comprising a body moving mechanism . 4. The pre-heating means is a means for heating the intermediate transfer member.
With respect to the moving direction, the first pressing body and the second pressing body
And the second member sandwiching the intermediate transfer member and the recording medium.
Preliminary addition of the intermediate transfer member on the upstream side of the transfer position.
The toner image transfer fixing device according to claim 2 Symbol mounting, characterized in that it is intended to heat. 5. The pre-heating means is provided for the intermediate transfer member.
With respect to the moving direction, the first pressing body and the second pressing body
And the nip width that sandwiches the intermediate transfer member and the recording medium.
Preheat the intermediate transfer over a larger area
The toner image transfer according to claim 2, wherein
Copy fixing device. 6. The preheating means is a silicone rubber
A toner image according to claim 5, which is a heater.
Transfer fixing device.