JPH086411A - Elastic roller, heating device and image forming device - Google Patents

Abstract

PURPOSE:To make fixing property excellent, to secure sufficient durability even in a low temperature state and a low pressure state and to obtain an excellent image extending over a long term by providing a specified-thickness fluorin-contained rubber layer which is harder than the elastic layer of a base layer between the base layer and a surface layer. CONSTITUTION:A pressure roller 2 being as a pressure rotating body is constituted of a core bar 2a, the elastic layer 2b being as the base layer formed on the outside circumference of the core bar 2a, the fluorin-contained rubber layer 2c which is formed on the outside circumference of the layer 2b and which is harder than the base layer 2a and a fluororesin layer 2d formed on the outside circumference of the layer 2c. Then, the roller 2 is disposed to press-contact with the surface of a heating body 6 by interposing a film 1 with prescribed pressing force by a bearing means and a pressing means. In such a case, the layer thickness of the layer 2c is set to be 5-10mum. When it is thinner than 5mum, the surface layer is cracked and the fluororesin of the surface layer does not become a film. When it is thicker than 10mum, it is not preferable because there is a possibility that the roller 2 becomes harder and a sufficient nip part is not formed because of the low pressure.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a heating device of a film heating type, that is, a heat-resistant film is brought into close contact with a heating member by a pressure rotating member and slid and conveyed, and the heat-resistant film is sandwiched between the heating members. The heat-resistant film in the pressure contact nip portion formed by the pressure roller and the pressure roller is introduced with a material to be heated, and the heat of the heater is transferred to the pressure contact nip portion together with the film to convey the heat of the heater. A heating device of a method of applying to a material to be heated via, an elastic roller used as a pressure rotating body in a heating device of a heating roller system, a heating device using the elastic roller,
The present invention also relates to an image forming apparatus including the heating device as an image heating and fixing device.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus such as a copying machine, a laser beam printer, a facsimile, a microfilm reader printer, an image display (display) device, a recording machine, etc., it is necessary to use an electrophotographic, electrostatic recording, magnetic recording, etc. A recording material (electrofax sheet, electrostatic recording sheet, transfer material sheet, etc.) as an image support is formed by using a toner made of a heat-meltable resin or the like by the image forming process means.
Unfixed toner image (fixed image) corresponding to the target image information formed on the surface of printing paper etc. by direct method or indirect (transfer) method is permanently fixed to the surface of the recording material carrying the image. As an image heating stationary device for performing heat fixing processing as an image, a contact type fixing device such as a heating roller type fixing device using a heating roller (fixing roller) or a film heating type fixing device is often used.

In this type of system, a recording material on which a toner image, which is an unfixed image, is placed is conveyed between a rotating body forming a pair of a heating roller or a heating film provided with a heat source and a pressure-contacting roller pressed against the heating roller. Then, the toner is thermally fixed on the recording material.

FIG. 6 shows a schematic view of an example of a heating roller type fixing device.

The apparatus of this embodiment has a cylindrical heating roller 101 having a heating means such as a heater 101a therein, and rotates clockwise when fixing.

Reference numeral 102 denotes a pressure roller as a pressure rotator having a cylindrical shape, which is pressed against the heating roller 101 for fixing and is rotated counterclockwise.

A recording material P, which is conveyed from the right side by a conveying belt 103 and has unfixed toner T attached as a toner image, is pressed and heated by a heating roller 101 and a pressure roller 102 to be fixed, and leftward. Is discharged to.

Denoted at 104a and 104b are separation claws used for separation so as to prevent the recording material P from being wound around the heating roller 101 or the pressure roller 102 to cause conveyance failure.

Further, 106 is a felt-like oil pad impregnated with a releasing agent such as silicone oil having an appropriate viscosity, and 105 is a cleaning roller in which brush-like fibers are planted in a cylindrical shape. The cleaning roller 105 rotates to remove the toner residue adhering to the peripheral surface of the heating roller and also appropriately supplies the release agent.

The heating roller 101 has a thickness of 2 to 5 m, for example.
200 to 500 μm with an Al pipe of about m
Thick silicone rubber or Teflon coated ones were used.

The pressure roller 102 is, for example, about 10 m.
A core metal made of SUS of mφ and coated with silicone rubber at a thickness of about 3 mm was used.

On the other hand, the film heating type heating device is compared with other known heating devices such as a heat roller type, a hot plate type, a belt heating type, a flash heating type and an open heating type, or an image heating and fixing device. At.
A low heating capacity linear heating element can be used as the heating element, and a thin film having a low heating capacity can be used as the film, which enables power saving and shortens the wait time (quick start), and increases the temperature inside the unit. Can be suppressed. The image heating and fixing device is advantageous in that it can prevent offset because the fixing point and the separation point can be set separately, and that it can solve various drawbacks of other types of devices.

Not limited to the fixing device, it can be widely used as a means and a device for heat-treating a material to be heated, such as an apparatus for heating a recording material carrying an image to modify its surface property, a hypothetical apparatus, and the like.

FIG. 7 shows an outline of a film heating type apparatus (image heating and fixing apparatus). (A) is an enlarged cross-sectional model view of the main part, (b) is a side view of the pressure roller portion, (c).
Fig. 2 shows a plan view of the heating element with the middle part omitted and partially cut away.

Reference numeral 6 denotes a heating body (ceramic heater) fixedly supported on the support body 3. The heat-resistant film (fixing film) 1 is adhered to the heating body 6 by a pressure roller 102 as a pressure rotating body. Sliding and transporting the heat-resistant film 1
Recording to be image-fixed as a material to be heated between the pressure roller 102 and the heat-resistant film 1 in the pressure contact nip portion (fixing nip portion) N formed by the heating body 6 and the pressure roller 102 sandwiching the sheet. By introducing the material P and nip-conveying the pressure contact nip portion N together with the heat-resistant film 1, the heat of the heating body 6 is applied to the recording material P via the heat-resistant film 1 so that the heat is applied to the recording material P. The unfixed visible image (toner image) T is heated and fixed on the surface of the recording material P. The recording material P passing through the pressure nip portion N is separated from the surface of the film 1 and conveyed.

The heating element 6 is an elongated substrate 7 having heat resistance, insulation, and good thermal conductivity whose longitudinal direction is a direction perpendicular to the conveying direction a of the heat resistant film 1 or the recording material P as a material to be heated. A resistance heating element 5 formed along the length of the substrate at the center in the lateral direction on the front surface side of the substrate, power supply electrodes 5a and 5a at both longitudinal ends of the resistance heating element 5, and heating with the resistance heating element formed. It is a linear heating element having a low heat capacity as a whole, which includes a heat-resistant overcoat layer 8 for protecting the surface of the body and a temperature detecting element 4 such as a thermistor for detecting the temperature of the heating element provided on the back side of the substrate.

The heating element 6 is fixedly arranged by exposing the surface side, on which the resistance heating element 5 is formed and provided, downward and adhering it to the heater support 3 having rigidity and heat insulation.

The heating element 6 is an electrode 5a at both ends of the resistance heating element 5.
The resistance heating element 5 generates heat over the entire length in the longitudinal direction by supplying power to 5a, and the temperature is raised.
Is detected, and the detected temperature is fed back to a temperature control circuit (not shown) to control the energization of the resistance heating element 5 so that the temperature of the heating element is maintained at a predetermined temperature. That is, during fixing, the energization of the resistance heating element 5 is controlled so that the detection output of the temperature detecting element (thermistor) 4 becomes constant.

The heat-resistant film 1 is in the form of an endless belt, and one of the rollers, which is stretched around the endless belt, is used as a driving roller and is rotatably conveyed by the frictional force between the driving roller and the inner peripheral surface of the film. There is also a constitution in which the pressure roller 102 is used as a drive roller, or other than the pressure roller 102, it is rotatably conveyed by the frictional force between the drive roller provided on the outer surface of the film and the outer peripheral surface of the film. There is also a structure in which the long film is fed and conveyed.

The pressure roller 102 as a pressure rotating member is similar to the pressure roller 102 of the apparatus shown in FIG. 6, and is composed of a metal cored bar 102a and a heat-resistant rubber layer 102b such as silicone rubber having a good releasability. It is an elastic roller (of solid meat quality) (hereinafter referred to as a solid roller), and is arranged by pressing the film 1 with a predetermined pressing force by bearing means and urging means (not shown) and bringing it into pressure contact with the surface of the heating body 6. I am doing it. When the pressure roller 102 is used as a film drive roller, a rotational force is transmitted to the roller 102 from a driving means (not shown) and the roller 102 is rotationally driven counterclockwise as indicated by an arrow.

[0021]

The function required of the fixing device as such a heating device is that the fixing property is secured without causing offset, and wrinkles occur in the recording material as the heated material. It has good releasability.

However, in the above-mentioned prior art, the pressure rotating body 10 is used.
A solid roller made of silicone rubber or the like is used as 2, but it is difficult to maintain the releasability of this solid roller for a long period of time. However, there is a problem that a jam of the recording material occurs.

In order to maintain the releasability of the solid roller, there is a method of impregnating silicone oil to improve the durability. However, this causes a large change in the outer diameter of the pressure roller due to the durability. In the method of driving the film by driving the pressure roller of the film fixing system, as the durability increases, the silicone oil volatilizes and the outer diameter of the roller becomes smaller, so the transport speed changes and the image printing characteristics are not satisfied. There's a problem.

From the above, in order to coat the surface of the roller with a fluororesin having excellent releasability, an elastic layer is provided on the roller core metal, and a fluororubber layer containing the fluororesin is formed on the elastic layer and baked. Thus, an elastic roller having a fluororesin projected on the surface has already been proposed, but this has a problem that the fluororesin layer has only about 2 to 3 μm and is poor in durability.

Although an elastic roller has been already proposed in which a fluororesin layer is further provided on the above structure, the roller hardness is increased in such a structure, which is excessive compared with the case of using a solid roller. There is a problem that pressure and temperature must be applied.

Therefore, an object of the present invention is to propose an elastic roller which is excellent in releasability and durability, and which can obtain sufficient fixing property even if the pressure and temperature related to the apparatus structure are set low, and Provided is an image heating and fixing device which can be used as a pressure rotating member of a film heating type heating roller type heating device to obtain an excellent image for a long period of time. It is to provide an image forming apparatus used as.

[0027]

The present invention is an elastic roller, a heating device, and an image forming apparatus characterized by the following constitutions.

(1) The base layer has an elastic layer, and the outermost layer has a layer coated with a fluororesin layer. A fluororubber layer having a hardness higher than that of the base elastic layer is formed between the base layer and the surface layer. An elastic roller having a thickness of 5 to 10 μm.

(2) The elastic roller according to (1), characterized in that the elastic layer of the base layer is made of silicone rubber and has a material hardness of 30 ° or less (JIS-A).

(3) The elastic roller according to (1) or (2), wherein the outermost fluororesin is FEP and has a layer thickness of 5 to 30 μm.

(4) The elastic roller according to any one of (1) to (3) is used as a pressure rotating body, and a heat resistant film is sandwiched between the pressure rotating body and the heating body to form a heating body. Introduce a material to be heated between the heat resistant film in the pressure contact nip formed by the pressure rotating body and the pressure rotor to convey the heat contact film together with the heat resistant film to transfer heat from the heating element. A heating device which is applied to a material to be heated through a heat resistant film.

(5) The heating device according to (4), wherein the heat-resistant film is an endless film that is rotationally conveyed or an end film that is traveling and conveyed.

(6) The pressure rotator is rotationally driven, and the rotational force thereof causes the heat-resistant film to be rotatably conveyed or conveyed while closely sliding on the heater.
Alternatively, the heating device according to (5).

(7) The heat-resistant film is an endless film, and a part of the circumference of the film is always tension-free and is rotatably conveyed by the rotational driving force of the pressure rotator (4) or The heating device according to (6).

(8) An image heat fixing device in which the material to be heated is a recording material supporting an unfixed developer image to be image-fixed, and the unfixed developer image is heat-fixed on the recording material. The heating device according to any one of (4) to (7), characterized in that.

(9) An image characterized by comprising the heating device according to any one of (4) to (8) as an image heating fixing device for heating and fixing an unfixed developer image on a recording material. Forming equipment.

[0037]

With the above structure, the elastic roller has excellent releasability for a long period of time, and the adhesive force between the layers is good.
It has excellent durability and can keep the roller hardness low.

Further, a heating device (fixing device) of a film heating system or a heating roller system using the elastic roller as a pressure rotating body.
As a result, good heating and fixing properties can be obtained even at low pressure and low temperature, so that the apparatus can be made inexpensive.

A) The elastic layer as the base layer plays the role of obtaining a sufficient nip at a low pressure, and is, for example, silicone rubber or the like.

The elastic layer has a material hardness of 30 ° or less (J
IS-A) is preferred. When the thickness of the elastic layer is increased and the hardness thereof is decreased, the change in the outer diameter due to heat increases, and particularly when the pressure roller is driven, the image extends. In addition, when a high pressure is applied, the torque of the device is increased, which leads to an increase in the cost of the motor and the like.

B) The fluororubber layer provided between the base layer and the surface layer functions as an adhesive for coating the fluororesin, and has a higher hardness than the elastic layer of the base layer. The reason for this is that the fluorines are in close contact with each other, so that the coating properties are excellent.

The layer thickness of the fluororubber layer is 5 to 10 μm.
And If the thickness is less than 5 μm, the surface layer is cracked and the surface fluororesin does not form a film. When it is thicker than 10 μm, the roller hardness is increased, and there is a possibility that a sufficient nip cannot be obtained at low pressure, which is not preferable.

C) The outermost fluororesin plays a role of ensuring toner releasability for a long period of time.
EP, PFA, PTFE, etc.

The layer thickness of this fluororesin layer is 5 to 30 μm.
m. If it is thinner than 5 μm, the releasability may be lost when printing 100,000 sheets or more, and if it is thicker than 30 μm, the roller hardness may increase and a sufficient nip may not be obtained at low pressure, which is not preferable. .

[0045]

【Example】

<Embodiment 1> (FIG. 1) FIG. 1 shows an image heating and fixing device A as a heating device of this embodiment.
It is a cross-sectional model figure of an example. The device A of this example is disclosed in
-44075-44083 gazette, the same 4-204980.
This is a so-called tensionless type film heating system device disclosed in Japanese Patent No. 204984.

That is, a heat-resistant film 1 having a cylindrical shape is used, and at least a part of the circumference of the film is tension-free (a state in which no tension is applied), and the film 1 is pressed as a pressure rotator. It is adapted to be rotationally driven by the rotational driving force of the roller 2. (1) Overall configuration of the apparatus 10 is a gutter-shaped film inner surface guide stay having a substantially semi-circular cross-section, and has the low heat capacity described above (FIG. 7) in a groove formed along the length on the outer lower surface of the stay. The heating element 6 is fitted in and fixedly supported.

The cylindrical film 1 is fitted onto the stay 10 including the heating body 6. The inner peripheral length of the cylindrical film 1 and the outer peripheral length of the stay 10 including the heating body 6 are larger than those of the film 1 by, for example, about 3 mm. The length fits loosely with a margin.

The pressure roller 2 as a pressure rotator is formed on the outer periphery of the core metal 2a, the elastic layer 2b as the base layer formed on the outer periphery of the core metal 2a, and the outer periphery of the elastic layer 2b, as described later. The fluororubber layer 2c having higher hardness than the base layer 2a
And a fluororesin layer 2d formed on the outer periphery of the film. The film 1 is sandwiched with a predetermined pressing force by bearing means and urging means (not shown), and the film 1 is placed in pressure contact with the surface of the heating body 6. is there. Then, the driving means M transmits the rotational driving force via a power transmission system (not shown) to rotationally drive it in the counterclockwise direction indicated by the arrow.

The rotation force of the pressure roller 2 causes a frictional force between the roller and the outer surface of the film to directly exert a rotation force on the film 1 (when the recording material P is introduced into the pressure contact nip portion N, A rotational force indirectly acts on the film 1 via the recording material P), and the film 1 is rotationally driven in the clockwise direction a as indicated by the arrow while sliding in pressure contact with the surface of the heating body 6. The film inner surface guide stay 10 facilitates rotation of the film 1. Further, in order to reduce the sliding resistance between the inner surface of the film 1 and the surface of the heating element 6, it is preferable to interpose a small amount of a lubricant such as heat resistant grease between them.

Thus, an unfixed image to be fixed on the image, which is fed to the fixing device A based on the press of the copy button of the copying machine such as a copying machine or the print command signal, or the image forming process means (not shown). Recording material P supporting the image T
Of the pressure roller 2 based on a signal when the front end of the sheet is detected by a sensor (not shown) provided on the front side of the fixing device A.
Is started to rotate, and heating of the heating element 6 is started.

When the peripheral speed of the film 1 is stabilized by the rotation of the pressure roller 2 and the temperature of the heating body 6 rises to a predetermined level, the film 1 is sandwiched between the heating body 6 and the pressure roller 2. The recording material P to be image-fixed as a material to be heated is introduced between the film 1 and the pressure roller 2 in the pressure contact nip portion N, and the pressure contact nip portion N is nipped and conveyed together with the film 1. The heat of the heating body 6 is applied to the recording material P via the film 1, and the unfixed visible image T on the recording material P is heated and fixed on the surface of the recording material P. The recording material P passing through the pressure nip portion N is separated from the surface of the film 1 and conveyed.

In the tensionless type film heating type apparatus of this embodiment, the pressure contact nip portion N and the film inner surface guide stay outer surface portion on the upstream side of the pressure contact nip portion N in the film rotation direction are in contact with the film when the film is rotationally driven. Tension acts only on the film part in the contact area,
Tension does not act on most of the rest of the film.

Therefore, when the film is driven to rotate, the displacement force of the film 1 along the length of the stay is small,
The film shift control means or the film shift control means can be simplified. For example, the film shift control means can be a simple member such as a flange member that receives the film end portion, and the film shift control means can be omitted to reduce the cost and size of the apparatus. (2) Elastic Roller 2 (Pressure Rotating Body) The elastic roller 2 as the pressure rotating body used in this embodiment has the following specific configuration.

That is, aluminum of 10 mmφ (A5056)
A peripheral surface of a cored bar 2a made of the above material was coated with an addition type silicone rubber (material hardness 18 ° product (JIS-A)) having a thickness t = 3 mm as an elastic layer 2b as a base layer.

A primer is applied to the upper surface of the elastic layer 2b, and fluororubber (material hardness 60 ° product (JIS-A)) is applied on the primer.
Is applied as a rubber layer 2c to 8 μm and fired, and a fluororesin (FEP) is further applied as a release layer 2d on the upper surface of the rubber layer 2c.
Was coated (coated) with a layer thickness t = 10 μm and baked.

The elastic roller 2 as the pressure rotating member is
A comparison test was performed with a roller having the same outer shape manufactured by a conventional technique.

The fixing device used in the comparative test is the tensionless type film heating system shown in FIG.

The test conditions are: Process speed 48 mm / sec. Heating body temperature control temperature 160 ℃. The total applied pressure is 5 kg / A4 size. Table 1 shows the durability (sheet passing number, K; 1000 sheets) and fixability when various pressure rollers are used.

[0059]

[Table 1] As can be seen from this result, No. 1 satisfies the releasing durability and the fixing property under the test conditions. No. 7 "core + silicone rubber + fluoro rubber + fluoro resin" only.
Other rollers have good durability, but the fixing ability is one rank lower. 4 or No. The fixability of No. 6 is 7
In order to obtain the same level as when using, the temperature and pressure must be increased. When using the pressure roller of 4 "core bar + silicone rubber + PFA tube", increase the pressure 1.5 times or the temperature is 10 deg.
If the pressure is not increased and the pressure is increased 1.3 times, the above No. 7
The same fixing property as when using the roller No. cannot be obtained. This not only leads to an increase in torque as the fixing unit, but also causes other adverse effects such as the need to increase the strength of other portions constituting the fixing device.

<Embodiment 2> (FIGS. 2 to 4) FIGS. 2 to 4 show other examples of the configuration of a film heating type heating device.

In FIG. 2, the first film suspension roller 31, the second film suspension roller 32, and the heating member 6 are provided between the three members 31, 32, 6 which are parallel to each other, and are in the form of an endless belt. The heat-resistant film 1 of
The pressure roller 2 is disposed by being pressed against the heating body 6 with the
The heat-resistant film 1 is rotated and conveyed as the first film suspension roller 31 or the pressure roller 2 as the film drive roller. First film suspension roller 3
When 1 is a driving roller, the pressure roller 2 is driven to rotate.

In FIG. 3, an endless belt-shaped heat-resistant film 1 is suspended and stretched between two members 2 and 33 of a heating body 6 and one film suspension roller 33, and the film 1 is sandwiched and pressed. The roller 2 is arranged in pressure contact with the heating element 6, and the heat-resistant film 1 is rotated and conveyed a as a film suspension roller 33 or the pressure roller 2 as a film drive roller. When the film suspension roller 33 is used as a driving roller, the pressure roller 2 is driven to rotate.

The heat-resistant film 1 shown in FIG.
Instead of an endless belt-like one, a long end film wound in a roll is used, and this is wound from the feeding shaft 34 side to the winding shaft 35 side via the heating body 6,
The pressure roller 2 is pressed against the heating body 6 with the film 1 sandwiched therebetween, and the film 5 is transported and conveyed to the winding shaft 35 side. The pressure roller 2 may be a film driving roller.

In each of the apparatus shown in FIGS. 2 to 4, the pressure roller 2 is the No. 1 of the first embodiment. By using “core metal + silicone rubber + fluorine rubber + fluorine resin” as in 7, it is possible to obtain the same effect as that of the first embodiment.

<Third Embodiment> (FIG. 5) FIG. 5 shows an example of an image forming apparatus incorporating an image heating and fixing device A as a film heating type heating device according to the present invention as shown in the first embodiment. Shows a schematic configuration of. The image forming apparatus of this embodiment is a reciprocating platen type, a rotary drum type, a transfer type, and a process cartridge attaching / detaching type electrophotographic copying apparatus.

Reference numeral 50 denotes an apparatus casing, 51 denotes a reciprocating type document placing table made of a transparent plate member such as a glass plate disposed on an upper surface plate 52 of the apparatus casing. In the drawing, they are reciprocally driven to the right a and the left a'at a predetermined speed.

Reference numeral G denotes an original document, which is placed on the upper surface of the original document table 51 according to a predetermined placement standard with the image surface side to be copied facing downward, and the original document pressing plate 53 is placed on the original document table 53 and pressed down. Set.

Reference numeral 54 designates the original placing table 51 on the upper surface plate 52 of the machine case.
The reciprocating direction is a slit opening serving as a document illuminating section which is opened with a direction at right angles (direction perpendicular to the paper surface) as the longitudinal direction.

The original document G placed and set on the original document table 51
The downward image surface passes through the position of the slit opening 54 sequentially from the right side to the left side in the forward movement process of the document placing table 51 to the right side a, and the lamp 55 is passed in the passing process.
The light L is received by the slit opening 54 and the transparent original placing table 51 for illumination scanning, and the original surface reflected light of the illumination scanning light is imagewise exposed on the surface of the photosensitive drum 57 by the image element array 56.

The photosensitive drum 57 is, for example, a zinc oxide photosensitive layer.
A photosensitive layer such as an organic semiconductor photosensitive layer is coated and driven to rotate in a clockwise direction indicated by an arrow b around a central support shaft 58 at a predetermined peripheral speed. By receiving a uniform charging process and subjecting the uniformly charged surface to image formation exposure (slit exposure) of the document image, an electrostatic latent image corresponding to the image-formed exposure document image is formed on the surface of the photosensitive drum 57. It is formed in sequence.

This electrostatic latent image is sequentially visualized by a developing device 60 with toner made of resin or the like which is softened and melted by heating, and the toner image as the visualized image is provided with a transfer discharger 61 as a transfer portion. It moves to the part.

Reference numeral S denotes a cassette in which transfer material sheets P as recording materials are stacked and housed, the sheets in the cassette are fed out and fed one by one by the rotation of the feeding roller 62, and then the drum is moved by the registration rollers 63. When the front end of the toner image forming portion on 57 reaches the portion of the transfer discharger 61, the front end of the transfer material sheet P is also transferred to the transfer discharger 61 and the photosensitive drum 5.
7 is reached and the sheets are synchronously fed with the timing so that they reach the position and coincide with each other.

Then, the toner images on the side of the photosensitive drum 57 are sequentially transferred to the surface of the fed sheet by the transfer discharger 61.

The sheet to which the toner image has been transferred at the transfer portion is sequentially separated from the surface of the photosensitive drum 57 by a separating means (not shown), and is guided to the fixing device A by the conveying device 64 to carry the unfixed toner. The image is heated and fixed, and is discharged as an image formed product (copy) onto a discharge tray 67 outside the apparatus through a discharge roller 66.

The surface of the photosensitive drum 57 after the image transfer is subjected to removal of adhered contaminants such as transfer residual toner by the cleaning device 68, and is repeatedly used for image formation.

The PC is a process cartridge that is attached / detached to / from the cartridge attaching / detaching portion 70 in the apparatus main body 50. In the case of this example, the photosensitive drum 57 as an image bearing member and the charger 5
9, four developing devices 60, a developing device 60, and a cleaning device 68 are included and can be collectively attached to and detached from the main assembly 50 of the apparatus.

The elastic roller of the present invention is effective not only as the pressure roller of the heating device of the film heating system of each of the above-mentioned embodiments, but also as the pressure roller of the heating roller system of FIG.

[0078]

As described above, the elastic roller according to the present invention has excellent releasability and durability, and when used as a pressure rotating member in a film heating type heating roller type heating device or a fixing device, it is related to the structure of the device. Sufficient fixability can be obtained even if the pressure and temperature are set low. Especially, the film heating type fixing device has excellent fixability even at low temperature and low pressure and can secure sufficient durability for long-term use. There is an effect that an excellent image can be obtained.

Further, since there is no change in diameter due to durability, even when this roller is used as a film transport driving member, there is no change in transport speed due to durability, and it is also possible to prevent the formed image from shrinking due to durability. it can.

[Brief description of drawings]

FIG. 1 is a heating device according to a first embodiment (a schematic cross-sectional view of an image heating and fixing device).

FIG. 2 is a schematic view of another configuration example of the film heating type device (No. 1).

FIG. 3 is a schematic view of another configuration example of the film heating type device (Part 2).

FIG. 4 is a schematic view of another configuration example of the film heating type device (Part 3).

FIG. 5 is a schematic configuration diagram of an example of an image forming apparatus.

FIG. 6 is a schematic configuration diagram of an example of a heating roller type heating device (image heating and fixing device).

7 (a) is an enlarged cross-sectional model view of a main part of a film heating type heating device, FIG. 7 (b) is a side view of a pressure roller portion, and FIG. Lacking plane model diagram

[Explanation of symbols]

A General code of film heating type heating device (image heating and fixing device) 1 Heat resistant film 2 Pressure roller (pressing rotator) 2a Core metal 2b Elastic layer (silicone rubber) 2c Fluorine rubber layer 2d Fluorine resin layer 6 Heating Body (ceramic heater) N Pressure contact nip P Recording material as heated material T Toner image 101 Heating roller 102 Solid single-layer pressure elastic roller

Claims (9)

[Claims] 1. A base layer has an elastic layer, and an outermost layer has a layer coated with a fluororesin layer. A fluororubber layer having a hardness higher than that of the elastic layer of the base layer is formed between the base layer and the surface layer. An elastic roller having a thickness of 5 to 10 μm. 2. The elastic layer of the base layer is silicone rubber,
The elastic roller according to claim 1, which has a material hardness of 30 ° or less (JIS-A). 3. The fluororesin of the outermost layer is FEP and has a layer thickness of 5 to 30 μm.
Alternatively, the elastic roller described in 2 above. 4. An elastic roller according to claim 1 is used as a pressure rotating body, and a heat resistant film is sandwiched between the pressure rotating body and the heating body to rotate with the heating body. Introduce a material to be heated between the heat resistant film in the pressure contact nip formed by the body and the pressure rotating body, and convey the heat in the pressure contact nip along with the heat resistant film to heat the heat of the heat resistant film A heating device which is applied to a material to be heated through a heating device. 5. The heating device according to claim 4, wherein the heat-resistant film is an endless film that is rotatably conveyed or an end film that is conveyed and conveyed. 6. The pressurizing rotary member is rotationally driven, and the rotational force thereof causes the heat-resistant film to be rotationally transported or transported while closely contacting and sliding on the heating member. Heating device. 7. The heat-resistant film is an endless film, and a part of the circumferential length of the film is always tension-free and is rotatably conveyed by the rotational driving force of a pressure rotator. The heating device according to 6. 8. An image heating fixing device for heating a material to be recorded, which supports an unfixed developer image to be image-fixed, and heat-fixes the unfixed developer image to the recording material. The heating device according to any one of claims 4 to 7, wherein: 9. An image forming apparatus comprising the heating device according to any one of claims 4 to 8 as an image heating fixing device for heating and fixing an unfixed developer image on a recording material. .