JPH0363756B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in a toner image transfer and fixing method and apparatus using an intermediate transfer member.

Generally, in an image recording apparatus equipped with an intermediate transfer member, a toner image formed on a toner image carrier by developing a latent image with a developing toner is transferred to an endless belt-shaped or roll-shaped intermediate transfer member. The toner image transferred onto the intermediate transfer member is further transferred and fixed onto a transfer material such as transfer paper, thereby recording an image. According to such a device, it is possible to obtain high-quality recorded images, and a latent image once formed can be used multiple times by repeating development and transfer to record many identical images. This makes it possible to introduce a so-called retention method, which has the advantage of easily increasing the speed of image recording. In addition, even when a one-component conductive toner is used as a developing toner, it can be transferred to a transfer material made of plain paper, which has the advantage of simplifying the developing system and improving image quality. be.

Therefore, there are various strict conditions in order to simultaneously transfer and fix the toner image on the intermediate transfer member to the transfer material, and it is quite difficult to achieve good transfer and fixation of the toner image. be.

Conventionally, as described in Japanese Patent Publication No. 46-41679, for example, a transfer material is heated without heating the toner of the toner image on the intermediate transfer member, and the toner image is transferred by the heat of the transfer material. There are known means of fixation.

This method is preferable in that there is no risk of overheating the intermediate transfer member and can prevent adverse thermal effects on the toner image bearing member, but it has a low heat utilization rate and is difficult to use for transfer materials made of ordinary paper. It is necessary to add a considerable amount of thermal energy. Moreover, the amount of thermal energy that should be applied to the transfer material usually differs depending on the type of transfer material made of paper. For example, transfer materials made of heavy paper or porous paper require a large amount of heat energy. If the same amount of thermal energy is applied to a transfer material made of paper with a small weight or thickness, it will become overheated.
The transfer material may become deformed or burnt, and in order to achieve good transfer fixation,
It is necessary to adjust the supplied thermal energy depending on the type of thermal transfer. Furthermore, when transferring and fixing toner images at high speed, it is necessary to apply even more heat energy to the transfer material, and as a result,
Energy consumption increases, and if the transfer material is not conveyed smoothly and jams occur, there is a great risk of fire.

On the other hand, as described in Japanese Unexamined Patent Publication No. 49-78559, by heating the toner of the toner image on the intermediate transfer body to its melting temperature without heating the transfer material, Means for transferring and fixing a toner image on a transfer material is also known.

However, with this method, the transfer material absorbs more heat than the toner, which reduces the fluidity of the toner on the side in contact with the transfer material, making it difficult to securely fix the toner. It is also necessary to heat the body considerably. As a result, heat is applied to the toner image carrier through the intermediate transfer member, and if the toner image carrier is an electrophotographic photoreceptor, the image density decreases due to a decrease in initial potential, and the material of the intermediate transfer member Fog occurs due to the components adhering to the surface of the toner image bearing member, and the intermediate transfer member deteriorates rapidly, making it impossible to obtain great durability.

In order to solve this problem, it may be possible to cool the intermediate transfer member in the movement path area after transfer and fixation, but forced cooling would consume even more energy, and natural cooling In this case, it is necessary to lengthen the moving path until the toner image bearing member comes into contact with the toner image carrier, resulting in an increase in the size of the apparatus.

In addition, during transfer and fixing, the toner is cooled first on the side that contacts the transfer material as described above, reducing its fluidity, so the toner is not completely transferred to the transfer material and a portion of it is transferred onto the intermediate transfer material. As a result, the toner image bearing member is contaminated and an offset phenomenon occurs.

The present invention has been made based on the above-mentioned circumstances, and is capable of reliably transferring and fixing a toner image on a toner image carrier to a transfer material by using an intermediate transfer member. This phenomenon does not occur, high resolution and high quality recorded images can be obtained even with the retention method, the selection range of toner component materials can be expanded, and moreover,
The object of this invention is to provide a toner image transfer and fixing method and device that consume less energy and can be configured compactly.

The above-mentioned object of the present invention is to provide a toner image transfer fixing method for transferring a toner image from a toner image carrier to an intermediate transfer member, and transferring and fixing the toner image from the intermediate transfer member to a transfer material. By pressing a pressing body heated to a temperature lower than the melting temperature and also heated to a temperature higher than the melting temperature of the toner to the intermediate transfer member, and feeding the transfer material heated to a temperature higher than the melting temperature of the toner into the pressure contact portion. A method for transferring and fixing a toner image, which is characterized in that the toner image is transferred and fixed onto the transfer material, and the toner image is transferred from the toner image carrier to an intermediate transfer member, and then retransferred from the intermediate transfer member to the transfer material. In the toner image transfer fixing device, the toner image is fixed by means for heating the toner image on the intermediate transfer member to a temperature lower than the melting temperature of the toner, a pressing member for pressing the transfer material against the intermediate transfer member, and the pressing member. the transfer material between the intermediate transfer body and the pressing body; This is achieved by a toner image transfer fixing device characterized in that the toner image is fed.

Note that in the present invention, the melting temperature of the toner is
The value determined by a Koka type flow tester (manufactured by Shimadzu Corporation) is used as the standard. In other words, measurements were carried out using a Koka-type flow tester under the conditions of a load of 20 kg/cm ² , a nozzle diameter of 1 mm, a nozzle length of 1 mm, and a temperature increase rate of 6°C/min, and when the plunger descent amount was h. The temperature at which the temperature drops by h/10 is defined as the melting temperature of the toner. A 1 cm ³ amount of toner is used as a sample for this measurement.

Hereinafter, the present invention will be explained based on illustrated examples.

FIG. 1 is an explanatory diagram of an embodiment of the present invention. In this example, a latent image forming mechanism 2, a developing mechanism 3, and a cleaning mechanism 4 are provided in this order according to the rotation method, and in the transfer area A between the developing mechanism 3 and the cleaning mechanism 4, an intermediate transfer body 5 made of an endless belt is pressed against the outer circumferential surface of the toner image carrier 1 by a pressing roller 6. Ru. The intermediate transfer body 5 is suspended by a heat roller 7 and a tension roller 8 in addition to a pressure roller 6, and is moved at a constant speed in the same direction as the toner image carrier 1 in the transfer area A. Heading towards the intermediate transfer body heating area B.

In the transfer fixing area C at or near the detachment point of the intermediate transfer body 5 on the heat roller 7,
A hot press roller 9 is provided between the heat roller 7 and the intermediate transfer body 5 and a transfer material (usually made of transfer paper), and the transfer material is transferred between the heat roller 7 and the heat press roller. A transfer material heating plate 10 is also provided which provides a transfer material heating area D along the transfer material moving path P immediately before being clamped and pressed by the transfer material heating plate 9.

In the apparatus configured as described above, the toner image T formed on the toner image carrier 1 as follows.
is finally transferred and fixed onto the transfer material.

First, the toner image T on the toner image carrier 1 is formed by developing the latent image formed by the latent image forming mechanism 2 with the developing mechanism 3. That is, when electrophotography is used, the toner image carrier 1 is composed of a selenium-based, organic compound-based, zinc oxide or cadmium sulfide-based binder type, or other electrophotographic photoreceptor, and has a latent image forming mechanism. 2, the entire outer circumferential surface of the toner image carrier 1 is electrically charged and then imagewise exposed to form an electrostatic latent image. When using electrostatic recording, the toner image carrier 1 is constructed of a dielectric material consisting of a conductive base and a dielectric surface layer, and the image signal is converted into an electrostatic latent image using a multi-stylus electrode or an ion control electrode. By doing so, a latent image is formed. When a magnetic recording method is used, the toner image carrier 1 may be made of a magnetic material, and the image signal may be converted into a magnetic signal by a magnetized head to form a magnetic latent image.

If the latent image formed in this way is an electrostatic latent image, the developing mechanism 3 makes the latent image visible using toner, which is colored charged particles charged to the opposite polarity to the charge forming the latent image. It is considered to be a statue. When the toner used here is a one-component conductive magnetic toner, development is achieved by the charge induced in the toner. When a one-component conductive magnetic toner is used and a magnetic brush development method is used, the toner layer is formed as a single particle layer or a thin layer close to it, so the image quality and durability of the final image are improved. It is particularly preferred because it has excellent high-speed developability and allows good transfer without selecting a transfer material. When the latent image is a magnetic latent image, it is sufficient to develop it with magnetic toner, and it is possible to prevent the occurrence of blurring of the image during transfer and to obtain a clear image.

Toner image bearing member 1 formed as described above
The upper toner image T is transferred onto the intermediate transfer body 5 in the transfer area A by the pressing force of the pressing roller 6.

The intermediate transfer member 5 includes a transfer layer made of a heat-resistant elastic material such as silicone rubber or fluorine-based rubber, and a heat-resistant substrate such as stainless steel plate, polyimide, polyimideamide, polyamide, polyester, polyarylate, etc. It is formed by a laminate with a heat-resistant polymer film such as a heat-resistant film made of resin (for example, "U sheet" manufactured by Ohira Kagaku Co., Ltd.), and the material of the transfer layer is room temperature vulcanization type or Particularly preferred is constant temperature vulcanization type silicone rubber. For example, "LTV1300",
"LTV1800" (both manufactured by Shin-Etsu Chemical Co., Ltd.) is an addition polymerization type silicone rubber, and is a particularly preferable material for the transfer layer. At low temperatures, these silicone rubber layers overcome the toner retaining force of the toner image carrier 1 in the transfer area A due to their moderate adhesiveness on the surface and the rubber elasticity that contains the toner, and sufficiently transfer the toner to the intermediate transfer body side. On the other hand, since the surface energy of the toner is sufficiently small compared to that of ordinary transfer material, the toner is heated from the surface of the toner on the transfer material side in the transfer fixing area C, which will be described later. When the transfer material is pressed in a fluid state, the toner strongly adheres to the transfer material and is almost completely transferred and fixed onto the transfer material. Since it is preferable that the toner image T and the intermediate transfer member 5 be heated at high speed by the heat roller 7, the thickness of the transfer layer and the substrate is preferably as small as possible within the range that provides the desired performance. The thickness of the transfer layer is 10~500
microns, the thickness of the substrate is optimally between 10 and 500 microns.

Note that the intermediate transfer body is not limited to endless belts.
For example, a transfer layer may be provided on the surface of a hollow roller made of aluminum or stainless steel, and a heater may be provided inside the hollow roller. When such an intermediate transfer member is used, the toner image transfer and fixing device can be made smaller and lighter than when a belt is used.

The illustrated heat roller 7 has a heater 7A made of, for example, an infrared lamp built into a hollow metal roller made of aluminum or the like, and controls the temperature of the surface of this metal roller to an appropriate range, thereby controlling the endless belt. In the area between the contact start point E with the intermediate transfer body 5 consisting of the intermediate transfer body 5 and the transfer fixing area C, that is, the intermediate transfer body heating area B, the intermediate transfer body 5 consisting of the endless belt and the toner image T formed thereon are Heat to a temperature below the melting temperature of the toner. Note that a heat-resistant elastic layer made of silicone rubber or the like may be provided on the surface of the heat roller 7.

The temperature of the intermediate transfer member 5 heated as described above is preferably as low as possible so that sufficient transfer and fixing can be performed on the transfer material in the transfer and fixing area C. This is because when the temperature of the intermediate transfer body 5 increases, the intermediate transfer body 5
As the toner image bearing member 1 is heated by the heat of This is because image deterioration occurs due to this. Therefore, if the temperature of the intermediate transfer member 5 becomes high, it is necessary to perform forced cooling before the transfer area A as in the conventional method.

The heat pressing roller 9 in the transfer fixing area C is a hollow metal roller made of aluminum or the like, or a heater 9A made of, for example, an infrared lamp is built into the hollow interior of which a heat-resistant elastic material surface layer such as silicone rubber is provided. The heat generated by the heater 9A is appropriately controlled so that the surface temperature of the thermal press roller 9 is appropriately set to be higher than the melting temperature of the toner of the toner image.

Further, the transfer material heating plate 10 in the illustrated example has a shape adapted to contact along the outer peripheral surface of the hot press roller 9, and transfers the transfer material between the surface of the hot press roller 9 and the transfer material heating plate 10. When the toner is passed through the toner, the toner is heated together with the hot press roller 9 to a temperature higher than the melting temperature of the toner. As a result, the toner image on the intermediate transfer member 5 is sufficiently transferred and fixed onto the transfer material in the transfer and fixing area C. Here, the friction coefficient of the surface of the hot press roller 9 is made larger than that of the surface of the transfer material heating plate 10, thereby,
The movement of the transfer material is accompanied by the movement of the surface due to the rotation of the hot press roller 9, and in order to improve heating efficiency, the transfer material is moved in contact with the surface of the fixed transfer material heating plate 10. However, the image is smoothly transported to the transfer and fixing area C. The transfer material heated in this way overlaps the intermediate transfer member 5, which has been heated in advance together with the toner image by the heat roller 7, in the transfer fixing area C, and the overlap is formed between the heat roller 7 and the toner image. Since the toner image is clamped by the hot press roller 9 heated to a temperature higher than the melting temperature, at least the side of the toner in contact with the transfer material is melted by the heat from the transfer material, and is further pressed against the toner. In this way, the toner image on the intermediate transfer member 5 is reliably transferred and fixed onto the transfer material.

As mentioned above, when bringing the transfer material into contact with the surface of the transfer material heating plate 10, it is important that the coefficient of friction between the transfer material heating plate 10 and the transfer material is small. It is effective to make the surface of the heating plate 10 smooth or to coat it with a material having a low coefficient of friction such as fluorocarbon resin. For example, coating materials such as aluminum and stainless steel with resins such as polytetrafluoroethylene, perfluoroalkoxy resins, polyfluoroethylene, and propylene, or mixing and dispersing metal powder, inorganic oxides, etc. in such resins. For example, coating with "Rulon" (manufactured by Deinox), or Taflam treatment, in which a porous material treated with hard alumite is impregnated with Teflon (registered trademark), is particularly effective in terms of wear resistance and low coefficient of friction. Are better. Further, the coating treated with the above coating or the Toughflam treatment has a low surface energy and does not accumulate dirt such as toner, and is also excellent in this respect. moreover,
A metal plate with a mirror surface made of hard chrome plating is also a preferred material. The heater for the transfer material heating plate 10 is preferably one processed into a plate shape. A PTC plate made of a resistance heating element having positive temperature characteristics does not require temperature control and is advantageous in terms of power consumption.

Although it is preferable that the heat transfer surface of the transfer material heating plate 10 contacts the transfer material as described above, it may partially contact the surface of the transfer material. Furthermore, if they are very close together, it is possible to obtain a sufficient heating effect without necessarily touching them. In this case, the distance from the surface of the transfer material is usually 3 mm.
The following shall apply. Alternatively, it is also effective to heat the transfer material by providing a pinch roller system using a heat roller in front of the transfer and fixing area C.

The transfer material that has passed through the transfer fixing area C is normally conveyed along the intermediate transfer body 5 and separated from the intermediate transfer body 5 by a tension roller 8 . Here, if the diameter of the tension roller 8 is made small, the transfer material can be easily separated from the intermediate transfer body 5, but by making it swing further, the intermediate transfer body 5 consisting of an endless belt can be easily separated. It is also possible to prevent deviation.

The intermediate transfer body 5 that has passed through the transfer fixing area C is naturally cooled, and is transferred again in the transfer area A.
Furthermore, the transfer and fixing process is repeated in the transfer and fixing area C.

In the figure, reference numeral 11 denotes a cleaning roller, which removes toner when it adheres to the hot press roller 9.

In the present invention, as described above, the toner of the toner image on the intermediate transfer member 5 transferred from the toner image carrier 1 is heated to a temperature lower than the melting temperature together with the intermediate transfer member 5 that supports the toner. While heating, the transfer material is heated above the above melting temperature,
Since the intermediate transfer body 5 and the transfer material are brought into pressure contact with each other in this state, it is possible to transfer and fix the toner image onto the transfer material without disturbing the state of the toner image.

That is, in the intermediate transfer body heating region B, the toner forming the toner image is only heated to a temperature at which it remains in a solid state without melting or in a state where it deforms under pressure. The toner image that reaches the fixing area C is in the same state as transferred from the toner image carrier 1, and there is no disturbance of the image due to fluidity of the toner, and moreover, the toner in this state is transferred in the transfer fixing area C. The material is pressure welded. Then, due to the heat from the transfer material and the hot press roller 9, the temperature of the toner rises from the side that contacts the transfer material, and this portion melts.
Furthermore, since the toner is deformed by pressure and adhered to the transfer material, the toner is not crushed and no smearing occurs, and the toner is transferred and fixed while maintaining high resolution. Moreover, since the toner remains in a solid state or a high viscosity state, offset phenomenon is extremely unlikely to occur.

Note that the heating efficiency of the transfer material by the transfer material heating plate 10 decreases when attempting to heat the transfer material to a high temperature of 100° C. or higher, for example. Therefore, the transfer material heating plate 1
0, the transfer material is only heated to a temperature slightly higher than the melting temperature of the toner of the toner image, and the transfer material is pressed against the intermediate transfer body 5 by the hot pressing roller 9 heated to a temperature higher than the melting temperature of the toner. preferable. As a result, the temperature of the transfer material is efficiently maintained above the melting temperature of the toner, and the interface temperature between the transfer material and the intermediate transfer member 5 and the toner temperature of the toner image are also increased, resulting in stable and reliable operation as described above. Make transfer fixation possible.

On the other hand, as described above, by heating the intermediate transfer body 5, its toner image, the transfer material, and the hot press roller 9 together, it is possible to reduce the heating temperature required for each of them. Therefore, it is no longer necessary to excessively heat each of them, and the amount of heat dissipated can be suppressed to a small level. This greatly improves the overall heat utilization efficiency, and together with this, the total energy consumption can be reduced. can be significantly reduced. Furthermore, it is also possible to transfer and fix toner images at high speed.

Furthermore, as described above, the temperature of the intermediate transfer body 5 that has passed through the transfer and fixing area C can be kept low, and there is no need to forcefully cool the intermediate transfer body 5, and cooling by natural heat radiation is sufficient. Even if the toner image bearing member 1 has a basic characteristic of being sensitive to heat, such as a photoconductive photoreceptor, its good characteristics are not impaired;
Alternatively, inconveniences such as a part of the material components of the intermediate transfer member 5 adhering to the toner image carrier 1 can be prevented, and the intermediate transfer member 5 is not heated to high temperatures or exposed to severe temperature changes. As a result, its durability can be maintained for a long period of time, or the heat resistance conditions required for the material of the intermediate transfer body 5 can be relaxed, the range of material selection can be expanded, and costs can be reduced. can be achieved. However, in the present invention, forced cooling of the intermediate transfer member 5 and the toner image bearing member 1 is not prohibited. Since toner fixation is performed as described above, the toner image in the transfer and fixing area C is almost completely separated from the intermediate transfer member 5, so that no toner is left on the intermediate transfer member 5 after transfer and fixation. Since no toner particles remain, staining of the toner image carrier 1 and occurrence of offset phenomenon can be prevented.

2 and 3 show cases in which the surface temperature of the thermal press roller 9 is set to be lower than the upper surface temperature of the intermediate transfer member 5 in the apparatus shown in FIG. 1, and the upper surface temperature of the intermediate transfer member 5, respectively. The thermal roller 7 is of course higher than the toner melting temperature of the toner image on its upper surface.
, the upper surface temperature T ₅ of the intermediate transfer member 5 in the vicinity of the clamping point of the thermal press roller 9, the transfer surface temperature T _P of the transfer material, and the temperature change of the surface temperature T ₉ of the thermal press roller 9. Note that the horizontal axis indicates the distance taken in the rotational direction of both rollers, with the position immediately before the clamping point of the heat roller 7 and the heat press roller 9 as 0.

Even if the transfer surface temperature T _P of the transfer material just before it enters the nipping point between the heat roller 7 and the heat press roller 9 is made higher than the toner melting temperature of the toner image by the transfer material heating plate 10, the heat press roller 9 If the surface temperature of the intermediate transfer member 5 is set to be lower than the upper surface temperature of the intermediate transfer member 5, the transfer surface temperature T _P of the transfer material will suddenly drop as shown in Fig. 2 because the heat capacity of the transfer material is small. Therefore, the temperature of the upper surface of the intermediate transfer body 5, that is, the temperature of the toner image does not exceed the melting temperature of the toner, and therefore the toner image is not transferred and fixed onto the transfer material. In this case, as can be seen from the temperature changes at T _P , T ₅ , and T ₉ in FIG. 2, the hot press roller 9 rather has a cooling effect on the transfer material and the intermediate transfer body 5. On the other hand, if the surface temperature of the hot press roller 9 is set higher than the toner melting temperature, even if the transfer surface temperature T _P of the transfer material drops once, it will rise again as shown in Figure 3. As a result, the upper surface temperature T5 of the intermediate transfer member ₅ is raised to a level higher than the toner melting temperature, and therefore the toner image is transferred and fixed onto the transfer material in the transfer fixing area C as described above. .

In the example shown in FIG. 1 described above, the intermediate transfer body 5 configured as an endless belt and the toner image transferred thereto are transferred by conduction from the heat roller 7 that also serves as a suspended support for the intermediate transfer body 5 and is in contact with the intermediate transfer body 5. It is heated by heat, which is preferable in terms of efficiency of heat use. In this case, it is desirable to heat the intermediate transfer member 5 by contacting the heat roller 7 at a center angle of 90 degrees or more. By making the intermediate transfer body heating area B sufficiently large in this way, when the transfer fixing area C is reached, the intermediate transfer body 5 and the heat roller 7
The temperature of the toner on the intermediate transfer body 5 can be controlled with high precision just before it enters the transfer and fixing area C, and stable transfer and fixation can be performed. Additionally, by making the heat roller 7 smaller in diameter, the apparatus can be made more compact.

In order to heat the intermediate transfer member 5 and the toner of the toner image, as shown in FIG. 4, the heat roller 7 is replaced with a simple roller 12, and a heat roller 13 having a heater 13A is brought into contact with the roller 12 and rotated. may be provided. The surface layer of the heat roller 13 is preferably formed of fluorine-based or syringe-based rubber to have mold releasability. In this case, it is desirable that the contact width between the roller 12 and the heat roller 13 be large.

FIG. 5 shows another embodiment of the present invention, in which a transfer material heating roller 14 having a heater 14A instead of the transfer material heating plate 10 in the example of FIG.
A transfer material guide plate 15 is further provided. As shown in FIG.
The toner image on the intermediate transfer body 5 is transferred to the transfer fixing area C along the transfer material guide plate 15 after being heated by the transfer heating roller 14 when passing through the intermediate transfer body 5. The image is transferred and fixed onto the material. Unlike the case shown in FIG. 1, the transfer material heating roller 14 instantaneously applies heat to the transfer material. The surface of the transfer material heating roller 14 is coated with a fluorine-based resin such as polytetrafluoroethylene, perfluoroalkoxy resin, or polyfluoroethylene/propylene, or subjected to Taflam treatment to prevent toner from adhering to the surface. It is preferable to impart mold releasability by using the toner, or a felt or a blade may be provided in parallel to remove adhering toner.

FIG. 7 shows still another embodiment of the present invention, in which an endless belt 17 is suspended between a pressure roller 9 and a tension roller 16, and a straight portion of the endless belt 17 is connected to a transfer material moving path P. A transfer material heating plate 10 is provided along and in opposition to the transfer material heating plate 10, and the transfer material heating plate 10 is rotatably supported on a support portion 18. 19 is a heater. According to such a configuration, it is possible to freely lengthen the contact time between the transfer material heating plate 10 and the transfer material, and it is possible to reliably heat the transfer material while moving it at high speed. In addition, the transfer material can be transported reliably, resulting in great reliability, and the transfer material heating plate 10 can be formed into a flat plate, making it easy to manufacture.

The material of the endless belt 17 is preferably a heat-resistant elastic material such as silicone rubber, polyimide, polyamide, etc., and its thickness varies depending on the material, for example, 0.1 to 5 mm, especially in the case of silicone rubber. is preferably 0.5 to 3 mm. It is preferable that the transfer material heating plate 10 be subjected to an appropriate surface treatment as described above to reduce its coefficient of friction and provide wear resistance and release properties. Further, in order to increase the frictional force with the endless belt 17, grooves may be formed on the outer peripheral surfaces of the pressure roller 9 and the tension roller 16, and in this case, the depth of the groove is preferably about 0.1 mm. . In addition, the tension roller 16 is
In order to prevent the endless belt 17 from shifting to one side, it is more preferable to use a crown roller having a larger outer diameter at the center than at both ends.

FIG. 8 shows another embodiment of the present invention. In this example, the transfer material heating roller 14 is installed independently of the thermal pressing roller 9 on the upstream side of the transfer fixing area C in the transfer material moving path P. , and a roller 20 that clamps and presses the transfer material. With this configuration, heating of the transfer material is performed independently of the hot press roller 9, so excessive heating of the hot press roller 9 is suppressed, and the transfer material is heated independently of the hot press roller 9.
0 merely has to perform the function of bringing the transfer material into pressure contact with the transfer material heating roller 14, so it is possible to improve the heating efficiency of the transfer material heating roller 14 and the accuracy of suppressing the heating temperature of the transfer material. Therefore, it is possible to prevent the offset phenomenon caused by excessive heating. Moreover, the heating of the transfer material is
Since this is carried out at a position separate from the press roller 9, the toner adhering to the pressure roller 9 is prevented from adhering to the transfer material due to heat. 15A and 15B are transfer material guide plates.

Next, examples of the present invention will be described.

Example 1 The toner used had a melting temperature of 100°C. As an intermediate transfer member, a belt-like intermediate transfer member was used, in which silicone elastomer RTV-KE1300 manufactured by Shin-Etsu Chemical Co., Ltd. was dissolved in toluene and sprayed to a thickness of 50 μm onto a belt-like polyimide base having a thickness of 50 μm. The primary image on the photoreceptor is transferred onto the intermediate transfer in the transfer section, and a rubber roll made of a 50φ2mm thick aluminum roll coated with 2mm thick silicone rubber is installed inside the intermediate transfer body, and a support roll and the inside of the support roll are placed inside the intermediate transfer body. The toner image on the intermediate transfer member was heated to 80°C along with the intermediate transfer member using a halogen lamp heater provided in the chamber. As a hot press roll, 1 roll is used for a 50φ2mm thick aluminum roll.
It is coated with silicone rubber with a thickness of mm, and is heated by a halogen lamp heater installed inside.
A transfer and fixing section was constructed by heating it to 200° C. and pressing it against an intermediate transfer member. A heating plate made by bonding a planar heating element with a film-shaped nichrome heating element embedded inside a plate-shaped silicone rubber plate to an aluminum plate.
When transfer paper heated to 120°C was passed through this transfer fixing unit at a line speed of 150 mm/min, it showed excellent fixing performance even under adverse conditions of high temperature and humidity, but it did not cause blurring or blurring of letters or lines. In addition, we were able to obtain a final image with good reproducibility, including solid black and half tones of photographs.

Example 2 The toner used had a melting temperature of 100°C. As an intermediate transfer body, silicone elastomer RTV-KE1300 manufactured by Shin-Etsu Chemical Co., Ltd. was dissolved in toluene on the surface of a rubber roll whose surface was a 2mm thick 50φ SUS roller coated with 2mm thick silicone rubber.
A roll-shaped intermediate transfer member spray-coated to a thickness of 100 μm was used. The primary image on the photoreceptor was pressure-transferred onto this intermediate transfer member in a transfer section, and this toner image was heated together with the intermediate transfer member to 80° C. by a heater of a halogen lamp provided inside the intermediate transfer member. As the pressure roll, a rubber roll made of a 50φ2 mm thick aluminum roll coated with 1 mm thick silicone rubber was used. A transfer and fixing section was composed of an intermediate transfer member and a hot press roll that pressed the intermediate transfer member. The hot press roll was heated to 200°C by a halogen lamp heater installed inside. 120
When transfer paper heated to ℃ was passed through this transfer fixing section at a line speed of 150 mm/min, it showed excellent fixing performance even under adverse conditions of high temperature and humidity, and there was no smearing or blurring of characters or lines. In addition, we were able to obtain a final image with good reproducibility, including solid black and half tones of photographs.

In the present invention, one of the requirements is that the intermediate transfer member has a temperature lower than the melting temperature of the toner, and the intermediate transfer member is desirably heated to a temperature of 1 to 40° C. lower than the melting temperature of the toner.

In addition, the pressing body is 0 to 150℃ higher, and the transfer material is 0 to 30℃ higher.
It is preferable to heat it to a high temperature.

As described above, according to the present invention, the toner image on the intermediate transfer member 5 can be reliably and suitably transferred and fixed onto the transfer material while maintaining high resolution, and the toner on the toner image carrier 1 can be transferred and fixed by pressure. Therefore, the latent image on the toner image carrier 1 is basically not destroyed, and by developing this latent image again, the same clear toner image is formed. Therefore, it is possible to reliably implement the retention method.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the configuration of an apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are curve diagrams showing temperature changes of an intermediate transfer body having a toner image and a transfer material in the example of FIG. 1. , FIG. 4 is an explanatory enlarged view of the main parts of the device in another embodiment of the present invention, and FIG.
The figure is an explanatory diagram showing the configuration of an apparatus in still another embodiment of the present invention, FIG. 6 is an explanatory enlarged view of a part of FIG. 5, and FIGS. It is an explanatory diagram showing the composition of the device in an example. 1... Toner image carrier, 2... Latent image forming mechanism,
3...Development mechanism, 5...Intermediate transfer body, 6...Press roller, 7...Heat roller, 7A...Heater, 8...
...Tension roller, 9...Heat pressure roller, 9A
... Heater, 10 ... Transfer material heating plate, 13 ... Heat roller, 14 ... Transfer material heating roller, 15 ... Transfer material guide plate, 16 ... Tension roller, 17
...Endless belt, 18...Support part, 19...Heater, A...Transfer area, B...Intermediate transfer body heating area, C...Transfer fixing area, D...Transfer material heating area, P...Transfer material Travel path, T... Toner image.

Claims (1)

[Scope of Claims] 1. A toner image transfer fixing method in which a toner image is transferred from a toner image carrier to an intermediate transfer member, and transferred and fixed from the intermediate transfer material to the transfer material, in which the toner image on the intermediate transfer member is transferred and fixed. A pressing body heated to a temperature lower than the melting temperature of the toner and heated to a temperature higher than the melting temperature of the toner is brought into pressure contact with the intermediate transfer body, and the transfer material heated higher than the melting temperature of the toner is fed into the pressure contact portion. A method for transferring and fixing a toner image, characterized in that the toner image is transferred and fixed onto the transfer material. 2. In a toner image transfer fixing device in which a toner image is transferred from a toner image carrier to an intermediate transfer member, and retransferred from the intermediate transfer member to a transfer material and fixed, the toner image on the intermediate transfer member is transferred to the toner image on the intermediate transfer member. a means for heating the transfer material to a temperature lower than the melting temperature of the toner; a pressing member for pressing the transfer material against the intermediate transfer body; a heating means for heating the pressing member to a temperature higher than the melting temperature of the toner; 1. A toner image transfer and fixing device, comprising a heating means for heating the transfer material to a temperature higher than the temperature, and feeding the transfer material between the intermediate transfer member and the pressing member. 3. The toner image transfer and fixing device according to claim 2, wherein the toner image carrier and the intermediate transfer member are respectively roll-shaped or belt-shaped rotating bodies. 4. The toner image transfer fixing device according to claim 2 or 3, wherein the upper surface of the intermediate transfer member is made of silicone rubber or fluorine rubber. 5. The means for heating the toner image on the intermediate transfer member is a heat roller that contacts the lower surface side of the intermediate transfer member and rotates the intermediate transfer member, and the means for heating the transfer material is a heat roller that rotates the toner image on the intermediate transfer member. The toner image transfer fixing device according to claim 3 or 4, wherein the toner image transfer fixing device is a heat pressing roller that presses and conveys the transfer body and the transfer material. 6. The intermediate transfer body is a belt-shaped rotating body,
6. The toner image transfer and fixing device according to claim 5, further comprising a pressure roller provided on the lower surface side of the intermediate transfer member for pressing the intermediate transfer member against the toner image carrier, in addition to the heat roller.