JPH0363758B2 - - 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.

In general, in an image recording device 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 roller-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 transfer material. Furthermore, when transferring and fixing toner images at high speed, it is necessary to apply even more thermal 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, the intermediate transfer body Means for transferring and fixing the above toner image onto a transfer material are 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 As the components adhere to the surface of the toner image bearing member, fogging occurs, and the intermediate transfer member deteriorates rapidly, making it impossible to obtain high 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 travel path until it 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 circumstances, and is capable of reliably transferring and fixing a toner image on a toner image bearing member to a transfer member by using an intermediate transfer member. No offset phenomenon occurs, it is possible to obtain high-quality recorded images with high resolution even with the retention method, it is possible to expand the selection range of toner component materials, and it consumes less energy and is compact. The purpose of this invention is to provide a toner image transfer and fixing device that can be constructed as follows.

The above-mentioned object of the present invention is to provide a toner image transfer and 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 member to a transfer material. A pressing member heated to a temperature lower than the melting temperature of the toner and higher than the melting temperature of the toner is brought into pressure contact with the intermediate transfer member, and a transfer material heated to a temperature lower than the melting temperature of the toner is fed 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 the intermediate transfer member, and is transferred from the intermediate transfer member to the transfer material again. In a toner image transfer fixing device that transfers and fixes the toner image,
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 a means for heating the pressing member to a temperature higher than the melting temperature of the toner. This is achieved by a toner image transfer fixing device characterized in that it is provided with means for heating the transfer material to a temperature lower than the melting temperature of the toner before bringing the transfer material into pressure contact with the intermediate transfer member.
In the present invention, the melting temperature of the toner may be based on a value measured with a Koka type flow tester (manufactured by Shimadzu Corporation). In other words, 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, when the blunger descent amount is h, the blunger is h/ The temperature at the time of 10 drops is the melting temperature of the toner. Toner is used as a material in an amount of 1 cm ³ .

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

FIG. 1 is an explanatory diagram showing 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 in the rotational direction, and in a transfer area A between the developing mechanism 3 and cleaning mechanism 4, an intermediate transfer member 5 made of an endless belt is transferred to a toner image carrier 1 by a pressing roller 6. is pressed against the outer peripheral surface of the 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,
Transfer material (usually made of transfer paper) is transferred to intermediate transfer body 5
A heat pressing roller 9 is provided to press the
The transfer material is fed to a pressure contact point with the intermediate transfer member 5 by a carry-in belt 17 suspended between the thermal pressure roller 9 and a tension roller 16 provided on the transfer material feeding side. In the illustrated example, a transfer material heating plate 10 for heating the transfer material to a temperature lower than the melting temperature of the toner is provided on the carry-in belt 17 on the tension roller 16 side.
0 can be rotated about axis 18 and moved away from carry-in belt 17 when not needed. B is a transfer material heating area.

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

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 electrostatic recording is used, the toner image carrier 1 is composed 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 carrier 1 may be made of a magnetic material, and an image signal may be converted into a magnetic signal by a magnetized head to form a magnetic latent image.

If the latent layer formed in this manner is an electrostatic latent image, the developing mechanism 3 makes the latent layer visible by toner, which is colored charged particles charged to the opposite polarity to that 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.

The toner image T formed on the toner image bearing member 1 as described above is transferred to the intermediate transfer member 5 in the transfer area A.
The image is transferred onto the surface 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 Taihei Kagaku Co., Ltd.), and the material of the transfer layer is a room-temperature vulcanization type or a heat-resistant polymer film made of resin. Low-temperature vulcanizable silicone rubber is particularly preferred. 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, the surface energy of the toner is sufficiently small compared to ordinary transfer material materials, so in the transfer fixing area C, which will be described later, the toner is heated from the surface of the transfer material side and flows. When the transfer material is brought into pressure contact with the toner in a sticky 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. Optimally, the thickness of the transfer layer is between 10 and 500 microns and the thickness of the substrate is 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 built-in heater 7A made of, for example, an infrared lamp inside 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 temperature of the endless belt. The intermediate transfer body 5 consisting of an endless belt and the toner image T thereon are transferred to the intermediate transfer body 5 consisting of an endless belt and the toner image T thereon in the region between the contact start point E with the intermediate transfer body 5 consisting of heating to a temperature below the melting temperature of the material. 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
When 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 that presses the transfer material against the intermediate transfer body 5 via the carry-in belt 17 in the transfer fixing area C is a hollow metal roller made of aluminum or the like with a built-in heater 9A made of, for example, an infrared lamp. This heater 9A
The heat generation is appropriately controlled so that the temperature of the carry-in belt 17 in contact with the thermal press roller 9 and the transfer material thereon is heated to be equal to or higher than the melting temperature of the toner. For this purpose, the carry-in belt 17 and the transfer material are
The transfer material heating plate 10 heats the transfer material in advance to a temperature as high as possible below the toner melting temperature. As a result, when the transfer material and the carry-in belt 17 reach the position where they are pressed against the intermediate transfer member 5 by the thermal pressure roller 9, the temperature easily reaches or exceeds the toner melting temperature due to heating by the heater 9A.

It is most preferable that the transfer material heating plate 10 heats the transfer material by contacting the surface of the transfer material on the carry-in belt 17. It is important that the transfer material heating plate 10 be small, and therefore it is effective to make the surface of the transfer material 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, and polyfluoroethylene/propylene, or mixing and dispersing metal powder, inorganic oxides, etc. in such resins. For example, coating with "Rulon" (manufactured by Denox Co., Ltd.) or Taflam treatment, which is a porous material treated with hard alumite and impregnated with Teflon (registered trademark), is effective in terms of wear resistance and low friction coefficient. Especially excellent. Furthermore, the coating treated with the above-mentioned coating treatment or the Toughflam treatment has a low surface energy and does not accumulate dirt such as toner, and is superior in this respect as well. Furthermore, a metal plate with a mirror surface formed by hard chrome plating is also a preferable material. Heater 1 of transfer material heating plate 10
9 is preferably processed into a plate shape, and a PTC plate made of a resistance heating element having positive temperature characteristics does not require temperature control or is advantageous in terms of the amount of electrons.

Although it is preferable that the transfer material heating plate 10 contacts the transfer plate 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 or less. 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 material of the carry-in belt 17 is preferably a heat-resistant elastic body such as silicone rubber, polyimide, polyimide amide, etc., and its thickness varies depending on the material, but is, for example, 0.1 to 5 mm, especially silicone rubber. In some cases, it is preferably 0.5 to 3 mm.
It is preferable that the transfer material heating plate 10 be appropriately surface-treated as described above to reduce its coefficient of friction and provide wear resistance and release properties. Further, in order to increase the frictional force of the carry-in belt 17, grooves may be formed on the outer peripheral surfaces of the hot press roller 9 and the tension roller 16, and in this case, the depth of the groove is preferably about 0.1 mm. . Tension roller 16
In order to prevent the endless belt 17 from shifting,
It is more preferable that the outer diameter of the central portion is larger than that of both end portions and that the crown roller is used.

With the above configuration, the length of contact between the intermediate transfer body 5 and the transfer material in the transfer fixing area C can be increased in the direction of movement of the transfer material, and the transfer material and the intermediate The interface of the transfer body 5 is heated to a temperature higher than the melting temperature of the toner,
At least the side of the toner image in contact with the transfer material is melted, and together with the pressure contact of the transfer material by the hot press roller 9, the toner image is reliably transferred and fixed onto the transfer material.

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, which is made of an endless belt, can be easily separated. It can also prevent bias.

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 body 5 transferred from the toner image carrier 1 is heated to a temperature lower than the melting temperature of the toner, together with the intermediate transfer body 5 that supports the toner image. At the same time, the transfer material is also heated to below the above melting temperature, and in this state, when the transfer material of the intermediate transfer body 5 is brought into pressure contact with each other by the hot press roller 9, it is heated above the toner melting temperature. Therefore, the toner image can be transferred and fixed 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. It is pressed against the material. Then, due to the heat transferred from the hot press roller 9 to the transfer material via the carry-in belt 17, the temperature of the toner rises from the side that contacts the transfer material, melting that part, and further, due to the pressure contact force. Since the toner is deformed and adhered to the transfer material, the toner is not crushed and no bleeding occurs, and therefore, 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.

In addition, by heating the intermediate transfer body 5 and its toner image, the transfer material and the carry-in belt 17, and the heat press roller 9, 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. It can be significantly reduced. It also becomes possible to transfer and fix toner images at high speed. Then, by setting the temperatures of the intermediate transfer body 5, the transfer material, the carry-in belt 17, and the thermal press roller 9, a rapid temperature gradient is generated inside the intermediate transfer body 5 in the transfer fixing area C, so that the surface of the intermediate transfer body 5 is And at least only the toner transfer material side of the toner image becomes higher than the melting temperature, and the intermediate transfer body 5
When the toner leaves the transfer fixing area C, heat diffusion occurs inside the intermediate transfer body 5, the temperature gradient inside the intermediate transfer body 5 disappears, and the temperature of the intermediate transfer body 5 can be suppressed to a low level. By lowering the temperature of the intermediate transfer body 5 due to the heat diffusion effect inside the intermediate transfer body 5, the surface of the transfer material is cooled by bringing the transfer material after transfer and fixation into contact with the intermediate transfer body 5, and an offset prevention effect is achieved. It can be further improved.

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 dissipation is sufficient, and the temperature of the toner image bearing member Even if 1 is a photoconductive photoreceptor, which has a sensitive property to heat in its basic characteristics, it does not impede its good characteristics, or if it is one of the material components of the intermediate transfer member 5. It is possible to prevent inconveniences such as adhesion of parts to the toner image bearing member 1, and the durability of the intermediate transfer member 5 can be maintained for a long period of time since the intermediate transfer member 5 is not heated to high temperatures or exposed to severe temperature changes. Alternatively, the heat resistance conditions required for the material of the intermediate transfer body 5 can be relaxed, the selection range of materials can be expanded, and costs can be reduced. However, in the present invention, the intermediate transfer member 5 and the toner image carrier 1
This does not prohibit forced cooling of 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, and therefore, the toner image is completely removed from 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.

FIGS. 2 and 3 show changes in the surface temperature of the intermediate transfer body 5 having a toner image and the surface temperature of the transfer material in the vicinity of the transfer and fixing section in the apparatus having the configuration shown in FIG. 1. In the figure, T ₅ indicates the surface temperature of the toner image and the intermediate transfer member 5, and T _P indicates the transfer surface temperature of the transfer material. The horizontal axis indicates the position taken in the transfer direction of the transfer material, with 0 being slightly before the point where the thermal pressing roller 9 presses the transfer material against the intermediate transfer body 5 via the carry-in belt 17.

Note that FIG. 2 shows the case where the transfer material is heated to 80° C. by the transfer material heating plate 10, and FIG. 3 shows the case where the transfer material heating plate 10 is not used. In both cases, the toner is melted. Use one with a temperature of 100℃,
The surface temperature of the hot press roller 9 is controlled at 200°C.

In either case of FIG. 2 or FIG. 3, the intermediate transfer body 5 is
The surface temperature T ₅ of the transfer material and the transfer surface temperature of the transfer material can be brought to be higher than the melting temperature of the toner, and the toner image can be completely transferred and fixed onto the transfer material. As described above, this increase in surface temperature of the intermediate transfer body 5 is limited to the surface, and when it leaves the transfer fixing area C, it rapidly cools down to below the toner melting temperature.

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 heated by conductive heat from the heat roller 7 that also serves as suspension support for the intermediate transfer body 5 and is in contact with it. This is preferable in terms of heat usage efficiency.

In this case, the intermediate transfer body 5 is moved to the heat roller 7.
It is desirable that the contact be made in the intermediate transfer body heating area B having a central angle of 90 degrees or more. By making the intermediate transfer body heating area B sufficiently large in this way,
When the transfer and fixing area C is reached, a state is obtained in which the temperatures of the intermediate transfer member 5 and the heat roller 7 are almost in equilibrium, and the toner on the intermediate transfer member 5 is transferred to the transfer and fixing area C.
The temperature immediately before the transfer can be controlled with high precision, and stable transfer and fixing can be performed, and by making the heat roller 7 small in diameter, the apparatus can be downsized.

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 made of Teflon-based or silicone-based rubber to provide release properties. 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.
are provided in opposition to the tension roller 16, and a transfer material guide plate 15 is further provided. Then, as shown in FIG. 6, the transfer material is heated by the transfer material heating roller 1.
4 and the tension roller 16, the transfer material is heated by the transfer material heating roller 14 and then reaches the transfer fixing region C along the transfer material guide plate 15. The toner image on the intermediate transfer body 5 is transferred and fixed onto the transfer material in the same manner as in the example shown in FIG. The transfer material heating roller 14
Unlike the case shown in FIG. 1, heat is instantaneously applied 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 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 for pinching the transfer material. According to such a configuration, since the transfer material is heated independently of the hot press roller 9 and the carry-in belt 17, the heat press roller 9 and the carry-in belt 17
Since excessive heating of the transfer material is suppressed and the roller 20 only has to perform the function of bringing the transfer material into pressure contact with the transfer heating roller 14, it is possible to improve the heating efficiency of the transfer material heating roller 14 and to reduce the heating temperature of the transfer material. Control accuracy can be improved, and offset phenomena due to excessive heating can therefore be prevented. Furthermore, since the transfer material is heated at a location separate from the hot press roller 9 and carry-in belt 17, toner adhering to the hot press roller 9 and carry-in belt 17 is prevented from adhering to the transfer material due to heat. Ru. 15A and 15B are transfer guide plates.

Example 1 The toner used had a melting temperature of 115°C. A belt-shaped intermediate transfer body 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 on a 50 μm belt-shaped polyimide substrate. The primary image on the photoconductor is transferred onto an intermediate transfer body in a 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 as a support roll. Internal halogen
The toner image on the intermediate transfer body and the intermediate transfer body were heated to 80° C. by the heater of the lamp. As the hot press roll, use a 50φ2mm thick aluminum roll coated with 1mm thick silicone rubber, heat it to 200℃ with a halogen lamp heater installed inside, and press it against the intermediate transfer body. A transfer and fixing section was constructed by the following. Transfer paper heated to 60℃ is transferred to this transfer fixing section using a heating plate made of a sheet heating element with a film-like nichrome heating element embedded in a silicone rubber plate attached to an aluminum plate at a line speed of 150mm/ When the paper was passed through the paper at the min paper feed speed, it showed excellent fixation even under adverse conditions of high temperature and humidity, and there was no smearing or smearing of characters or lines, and the final image had good reproducibility, including solid black and half tones of photographs. I was able to get the image.

Example 2 The toner used had a melting temperature of 115°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. Transfer paper heated to 80℃ is transferred to this transfer fixing section at line speed using a heating plate made of a sheet heating element with a film-like nichrome heating element embedded inside a plate-shaped silicone rubber bonded to an aluminum plate.
When the paper was passed through the paper at a feed speed of 150 mm/min, it showed excellent fixing properties even under adverse conditions of high temperature and humidity, and there was no smearing or smearing on letters or lines, and even black solids and half tones such as photographs were printed. We were able to obtain a final image with good reproducibility.

In the present invention, one of the requirements is to keep the intermediate transfer member at a temperature lower than the melting temperature of the toner, and therefore, the intermediate transfer member may be sent to the transfer and fixing position without being heated, but it is preferable to Heat and send. In that case, good results were obtained by heating the toner to a temperature 1 to 70° C. lower than the melting temperature of the toner. Similarly, the transfer material may be sent to the transfer and fixing position without being heated, but it is preferably heated to a temperature 1 to 70° C. lower.

Also, the pressing body is 0 to 150 degrees higher than the melting temperature of the toner.
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, the retention method can be realized reliably.

[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 figures are explanatory diagrams showing the configuration of a device in still another embodiment of the present invention, FIG. 6 is an explanatory enlarged view of a part of FIG. 5, and FIG. FIG. 2 is an explanatory diagram showing the configuration. 1... Toner 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 heating area,
C...Transfer fixing area, D...Transfer material heating area, P
...Transfer material movement path, T...Toner image.

Claims (1)

[Scope of Claims] 1. In 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 member to a transfer material, the toner image on the intermediate transfer member is transferred to a toner image on the intermediate transfer member. A pressing member heated to a temperature lower than the melting temperature of the toner and higher than the melting temperature of the toner is brought into pressure contact with the intermediate transfer member, and a transfer material heated to a temperature lower than the melting temperature of the toner is fed into the pressure contact portion. A toner image transfer and fixing method, comprising transferring and fixing a toner image onto the transfer material. 2. In a toner image transfer and fixing device in which a toner image is transferred from a toner image carrier to an intermediate transfer member, and then retransferred from the intermediate transfer member to a transfer material and fixed, the toner image on the intermediate transfer member is transferred to a toner melting temperature. a means for heating the transfer material to a lower temperature; a pressing body for pressing the transfer material against the intermediate transfer body; a means for heating the pressing body to a temperature higher than the melting temperature of the toner; 1. A toner image transfer fixing device comprising: means for heating the toner to a temperature lower than the melting temperature of the toner. 3. The toner image transfer and fixing device according to claim 2, wherein the intermediate transfer member is heated and maintained at a temperature lower than the melting temperature of the toner by a heating means. 4. The toner image transfer and fixing device according to claim 2 or 3, wherein the toner image bearing member and the intermediate transfer member are respectively roll-shaped or belt-shaped rotating bodies. 5. The toner image transfer and fixing device according to claim 2, wherein the upper surface of the intermediate transfer body is made of silicone rubber or fluorine rubber. 6. The heating means for the intermediate transfer body is a heat roller that contacts the lower surface side of the intermediate transfer body and rotates the intermediate transfer body, and the pressing body narrows the intermediate transfer body and the transfer material between it and the heat roller. The toner image transfer fixing device according to claim 3 or 5, wherein the toner image transfer fixing device is a thermal pressing roller that presses and feeds the toner image. 7. The intermediate transfer body is a belt-shaped rotating body,
7. The toner image transfer and fixing device according to claim 6, 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.