JP3070631B2 - Heating device and heating element - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a heating element provided on a substrate.
The heated body, and a film sliding with the heated body,
Having, by heat from the heating element through the film
The present invention relates to a film heating type heating device for heating an image on a recording material and a heating element .

[0002]

2. Description of the Related Art A heating apparatus of the above-mentioned film heating type is disclosed in Japanese Patent Application Laid-Open No. 63-31318 which has been proposed by the present applicant.
No. 2 publication, etc., and an image heating and fixing device in an image forming apparatus such as an electrophotographic copying machine, a printer, a facsimile, etc. Undetermined corresponding to the target image information, formed directly or indirectly (transferred) on the surface of a recording material (electrofax sheet, electrostatic recording sheet, transfer material sheet printing paper, etc.) using toner made of resin, etc. The developed image (toner image) can be utilized as an image heating and fixing device for performing heat fixing processing as a fixed image on a recording material carrying the image.

[0003] Further, for example, it can be used as a device for heating a recording material carrying an image to improve the surface properties such as gloss, or a device for performing a temporary deposition process.

More specifically, a thin heat-resistant film (sheet), a driving means for moving the film, and a heater (heater) fixedly supported and arranged on one side of the film with the film inside. And a pressure member disposed on the other surface side to face the heating element and closely contacting the visible image bearing surface of the recording material to be image-fixed to the heating element via the film, At least during execution of image fixing, the recording medium to be image-fixed, which is conveyed and introduced between the film and the pressing member, is moved at the same speed in the forward direction at the same speed, and the heating element and the pressing member are sandwiched by the traveling moving film. By passing through a fixing nip portion as a fixing portion formed by pressure contact with the recording medium, the developed image carrying surface of the recording material is heated by the heating body via the film to heat the developed image (unfixed toner image). Softening and melting by applying energy And then an image heating fixing apparatus of film heating type which is based on that to separate the recording material and the film after fixing portion passing through at the separation point.

[0005] The apparatus may be configured such that the film is made endless, rotated and conveyed, and used repeatedly, or may be configured such that an end rolled film is fed out and run. The pressurizing member can be rotated to drive the film.

FIG . 7 is an enlarged cross-sectional model view of a main part of such an apparatus.

Reference numeral 20 denotes a heater, which is provided with a heater substrate (ceramic substrate) 2 having heat resistance, electrical insulation and low heat capacity, and provided on one surface of the substrate 2 along a surface length (a direction perpendicular to the drawing). And a glass layer 21 on which the surface of the substrate 2 including the resistance heating element layer 3 is coated.

The glass layer 21 side of the heater 20 is a film contact sliding surface, and the glass layer 21 side is exposed to the outside so that the heater 20 is fixed to the support via the heat-insulating heater holder 4. It is supported. The temperature of the heating element 20 rises due to the heat generated by the heating element layer 3 due to energization of the resistance heating element layer 3.
Reference numeral 6 denotes a temperature detecting element of a heating body temperature control system.

Reference numeral 7 denotes a heat-resistant film, and reference numeral 10 denotes a film formed of the glass layer 2 serving as a film contact sliding surface of the heating element 20.
It is a rotary pressure roller as a pressure member for pressing one surface. The film 7 is pressed against the heating element 20 by the pressure roller 10 and moves while being in contact with the surface of the heating element 1 at a predetermined speed in a direction indicated by an arrow by driving means or by the rotational driving force of the pressure roller 10.

When the heating element 20 is heated to a predetermined temperature by energizing the resistance heating element layer 3 and the film 7 is slidably moved to the heating element 20, the film 7 and the pressure roller 10
The recording material 12 as a material to be heated is introduced into the press-contact nip portion (fixing portion) N with the recording material 12 so that the recording material 12 adheres to the surface of the film 7 and moves and passes through the position of the heater 20 together with the film 7.
In the moving passage process, heat energy is applied to the recording material 7 from the heating body 20 via the film 7, and the unfixed toner image 11 on the recording material 12 is heated and fused.

Conventionally, a heat roller system has been generally used as an image heating and fixing device. This is composed of a fixing roller having a heater inside a metal roller and a pressure roller having elasticity. The recording material is introduced and passed through a fixing nip formed by the pair of rollers to heat and heat the toner image. Fix by applying pressure.

However, in such a heat roller type image heating and fixing apparatus, since the heat capacity of the roller is large, it takes time (rise time, warm-up time, wait time) for the roller to reach a predetermined fixing temperature, and For quick use, the temperature must be controlled to a certain temperature even when the machine is not in use. The same applies to other heating type fixing devices such as a hot plate type and an oven fixing type.

On the other hand, in the above-described film heating type apparatus, since a low heat capacity heater can be used as the heating element 1, the weight time can be reduced (quick time) as compared with a conventional heat roller type apparatus or the like. Startability)
In addition, it enables quick start and eliminates the need for preheating when not in use, thereby saving power in a comprehensive sense. In addition, it can solve various disadvantages of other system devices. And is effective.

[0014]

The glass layer 21 serving as a film contact sliding surface of the heating element 20 directly contacts the film 7 with the surface of the heating element 20 provided with the resistance heating element layer 3 without this layer. When the film is slid, it has a role of a surface protective layer that prevents the film inner surface and the pattern of the resistance heating element layer 3 from being scraped and smoothly slides and moves the film.

The glass layer 21 has a role as an insulating material layer for preventing direct contact between the pressure roller 10 and the resistance heating element 3. That is, even when the film is torn and the pressure roller 10 as a film pressure member comes into contact with the heating element 20, the pressure roller 10 is interposed between the resistance heating element layer 3 of the heating element 20 and the heating roller 20. The pressure roller 10 and the resistance heating element 3 are insulated from each other, and the pressure roller 10 and the resistance heating element 3 come into direct contact with each other and the voltage applied to the resistance heating element 3
0 prevents the occurrence of an electrical short-circuit / leakage trouble on the entire apparatus.

When the thickness of the glass layer 21 is increased in order to increase the dielectric strength, the efficiency of heat transfer from the heating body 20 to the film 7 deteriorates, and the image fixing failure of the recording material due to insufficient heating tends to occur. Conversely, if the thickness is reduced to improve the heat transfer efficiency, the withstand voltage cannot be obtained.

The thermal expansion coefficient of the glass layer 21 is 5 × 10 ⁻⁶ ° C. ⁻¹ , and the thermal expansion coefficient of the ceramic substrate as the heater substrate 2 is 7 × 10 ⁻⁶ ° C. ^-1. When the thickness of the heating element 21 is increased, the heating element
Warpage occurs and mechanical stress (internal stress) acts strongly. In some cases, the glass layer 21 may be cracked, peeled off, or the heater substrate 2 may be broken. .

In view of the above, the present invention does not reduce the thickness of the glass layer as the insulating material layer of the heating element, ie, the thickness of the glass layer is sufficient for the film heating type heating apparatus and heating element. When the thickness is set so that the heat transfer efficiency from the heater to the film can be ensured, the warp of the heater and cracks in the glass layer caused by the difference in the coefficient of thermal expansion between the heater substrate and the glass layer can be ensured. It is an object of the present invention to provide a device capable of preventing occurrence of the above.

Further, the above-mentioned trouble caused by the existence of the glass layer is prevented from being caused even if the existence of the glass layer as the insulating material layer is made unnecessary or the glass layer as the surface layer is made to exist. The purpose is to provide things.

[0020]

SUMMARY OF THE INVENTION The present invention is a heating device and a heating element characterized by the following constitutions.

(1) A heating element having a heating element provided on a substrate
And a film that slides on the heating element.
The image on the recording material is generated by the heat from the heating element through the film.
In a heating device for heating an image, the heating element generates the heat.
A first glass layer provided on a body, and the first glass
A second glass layer provided on the layer and in contact with the film
And the first glass layer has a ceramic filler.
Dispersed, said second glass layer containing a ceramic filler.
A heating device characterized by not being covered .

(2) A substrate and a light source provided on the substrate
And a heating element, wherein the heating element is provided on the heating element.
A first glass layer provided on the first glass layer;
A second glass layer, which is a slidable sliding layer,
The first glass layer has a ceramic filler dispersed therein,
The second glass layer has no ceramic filler.
Heating body to be a symbol.

(3) A heating element provided with a heating element that generates heat by energization on a ceramic substrate, and a film that slides on the heating element, wherein the film is heated by the heat from the heating element via the film. In a heating apparatus for heating an image on a recording material, the heating element is in contact with the film on a surface of the ceramic substrate opposite to a surface on which the heating element is provided. (4) The heating device according to (3), wherein the heating body has a sliding layer on a surface of the ceramic substrate on the film side. (5) and the ceramic substrate, the heating element having a calling thermal body, and the sliding layer, wherein the heating element of the ceramic substrate
Is coated on a surface, the sliding layer coating of the surface opposite to the heating element is provided surface of the ceramic substrate
Heating body, characterized that you have been.

< Operation > (1) The film-contacting sliding surface of the heating element is coated with a glass layer in which a ceramic filler is dispersed, so that the ceramic filler-dispersed glass has the ceramic filler dispersed therein. The thermal conductivity is much higher than that of glass that is not made, and the dielectric strength is equal to or higher than that of glass that does not have a ceramic filler dispersed. Without increasing the thickness of the glass layer as a sliding protection / insulating material layer in order to increase the heat transfer efficiency, that is, the thickness of the glass layer is sufficient to ensure a sufficient withstand voltage, It is possible to ensure a sufficiently good heat transfer efficiency to the heat exchanger.

Further, by making the ceramic filler dispersed in the glass layer the same or equivalent material as the heater substrate of the heater, the coefficient of thermal expansion of the ceramic filler dispersed glass layer can be made close to that of the heater substrate. Becomes
It is also possible to reduce or prevent the occurrence of warpage of the heating element and cracks in the glass layer due to a large difference in thermal expansion coefficient between the heater substrate and the glass layer. Therefore, the heating element
A first glass layer provided on a heating element, and a first glass layer
A second glass layer provided on top and in contact with the film;
Wherein the first glass layer has a ceramic filler dispersed therein,
The second glass layer does not include a ceramic filler.
To improve heat transfer efficiency from the heating element
Sliding with the film can be performed well.

(2) The heating element is a ceramic substrate.
Contact the film on the side opposite to the side where the heating element is provided
With this configuration, the ceramic substrate itself has good thermal conductivity, so it is possible to secure a sufficient heat transfer coefficient from the heating element to the film without reducing the thickness, and it is possible to secure a sufficient withstand voltage. even the film is torn in contact with the heating member to the pressing member directly, the pressure member ceramic base of the heater
Since there is no resistance heating element layer that contacts the plate surface and generates heat when energized on the contact surface side, the insulation withstand voltage is sufficient.
There is no earth leakage trouble.

[0027] (3) further by providing a sliding layer for lubricity enhancing the film ceramic substrate surface as a film contact sliding surface of the heating body in the above (2),
Sufficient withstand voltage while ensuring heat transfer efficiency from the heating element
And the film can slide well.
You. In this case, the sliding layer does not need to have a high withstand voltage, so that its thickness can be reduced.
There is no problem of a decrease in the heat transfer coefficient from the heating element to the film due to the presence of the sliding layer .

Further generated stress since the sliding layer also in the internal stress in the heating member by the difference in thermal expansion coefficient between the said sliding layer and the ceramic substrate can be thinned is small, problems caused by the stress does not occur substantially.

[0029]

<Embodiment 1> (FIGS. 1 and 2) This embodiment is an embodiment of the invention described in claims 1 and 2. FIG.

FIG . 1 is a schematic structural view of an example of an image heating and fixing apparatus A as a heating apparatus according to the present invention, and FIG. 2 is an enlarged cross-sectional model view of a heating element portion of the apparatus.

The apparatus of this embodiment is of an apparatus configuration in which the film 7 is made to be an endless belt type, rotated and conveyed, and used repeatedly. (1) Overall Configuration of Apparatus Reference numeral 7 denotes an endless belt-shaped fixing film, which includes a driving roller 8 on the left side, a driven roller 9 on the right side, and a heating member fixedly supported below these rollers 8.9. The three members 8 parallel to each other with the low heat capacity linear heating body 1 as a body
・ It is stretched between 9.1.

The driven roller 9 also serves as a tension roller for the endless belt-shaped fixing film 7, and the fixing film 7 is wrinkled or meandered at a predetermined peripheral speed in a clockwise direction with the clockwise rotation of the driving roller 8. It is driven to rotate without delay.

Reference numeral 10 denotes a pressure roller having a rubber elastic layer having good releasability such as silicon rubber as a pressure member.
The downward film portion of the endless belt-shaped fixing film 7 is sandwiched between the heating member 1 and the lower surface of the heating member 1 to be pressed against the lower surface of the heating member 1 by a biasing means with a contact pressure of, for example, a total pressure of 4 to 7 kg. Recording material 1 as a material to be heated
2 rotates counterclockwise in the forward direction in the transport direction.

Since the endless belt-shaped fixing film 7 which is driven to rotate is repeatedly used for heating and fixing a toner image, it is excellent in heat resistance, releasability and durability.
A thin material having a thickness of 00 μm or less, preferably 40 μm or less is used.

For example, a single-layer film of a heat-resistant resin such as polyimide / (PI) / polyetherimide (PEI) / PES / PFA (ethylene tetrafluoride-perfluoroalkyl vinyl ether copolymer resin) or a composite layer film such as 20 μm A releasable coating layer obtained by adding a conductive material to a fluororesin such as PTFE (tetrafluoroethylene resin) or PFA is formed on at least the image contacting surface side of the thick film at a thickness of 10 μm.
Thickly applied.

The heating element 1 is a low heat capacity linear heating element (heater) having a longitudinal direction intersecting the film moving direction.
As shown in the enlarged cross-sectional model diagram of FIG. 1, the substrate 2 , the resistance heating element layer (electric heating element layer) 3 , the first glass layer 100 ,
It comprises the second glass layer 21, the temperature detecting element 6, and the like.

The substrate 2 is a ceramic substrate having heat resistance, electric insulation and low heat capacity, for example, a thickness of 1.0 mm and a width of 10 mm.
It is an alumina substrate with a length of 240 mm.

The resistance heating element layer 3 has a surface on one side of the substrate 2 on the film sliding side, and an electric resistance material such as Ta ₂ N / silver palladium having a width of 1 at substantially the center of the surface along the surface length. .
This is a linear or belt-like low heat capacity layer provided by coating (screen printing or the like) to 0 mm.

First glass layer 100 and second glass
Layer 21 is a film contact sliding surface, the resistance heating element layer 3 which was then coated surface of the substrate 2 comprising, to improve the lubricity of the film of pressure Netsutai 1, scraping of the film inner surface, In addition to preventing pattern abrasion of the resistance heating element layer 3, it also functions as an insulating material layer for preventing electrical short-circuit and electric leakage due to direct contact between the pressure roller 10 and the resistance heating element layer 3 when the film is broken. I have.

In this embodiment , the first glass layer 100 is a glass layer in which a ceramic filler is dispersed as described in the item (2) described later. The second glass layer 21 is made of ceramic.
It is a layer that does not contain a filler.

The heating element 1 is inserted into the heating element accommodating groove 4a provided on one surface of the horizontally long heating element holder (heater holder) 4 along the longitudinal direction of the glass layer 100 , 21.
The holder 4 is fixed and held by the adhesive 18 with the side facing outward, and the holder 4 is placed on the lower surface of the support 5 as a stationary member of the fixing device with the heating element 1 facing downward.
9 is fixedly supported.

The heating element holder 4 is made of, for example, PPS (polyphenylene sulfide), PAI (polyamide imide),
It can be composed of a high heat-resistant resin such as PI (polyimide), PEEK (polyetheretherketone), liquid crystal polymer, or a composite material of these resins with ceramics, metal, glass, or the like.

The heating element 1 energizes the linear or belt-shaped resistance heating element layer 3 from both longitudinal ends thereof to generate heat and increase the temperature of the resistance heating element layer. Energization is cycle 2 of DC100V
A pulse (drive pulse) having a pulse shape of 0 msec and corresponding to a desired temperature and energy release amount controlled by the temperature detecting element 6 and the microcomputer.
Is provided by changing the pulse width. The approximate pulse width is 0.5 to 5 msec.

In this embodiment, a sensor for detecting the leading and trailing ends of the recording material (not shown) is provided near the fixing device on the upstream side of the fixing device A in the recording material conveyance direction, and the sensor detects the recording material. The power supply period to the resistance heating element layer 3 is controlled only during the necessary period during which the recording material 12 passes through the fixing device A.

An image forming mechanism (not shown) performs an image forming operation in response to an image forming start signal, and the leading end of a recording material 12 carrying an unfixed toner image 11 on the upper surface and conveyed to the fixing device A is disposed closer to the fixing device. When the fixing film 7 is detected by the above-described sensor, the rotation of the fixing film 7 is started, and the recording material 12 is guided by the guide 16 to press the fixing film 7 at the pressure contact portion N between the heating body 1 and the pressure roller 10. The unfixed toner image enters the gap between the roller 10 and the surface of the unfixed toner image closely adheres to the lower surface of the fixing film 7 in the surface moving state and moves without causing surface misalignment or wrinkling. Heating body 1
It passes through a fixing nip N between the pressure roller 10 and the pressure roller 10 while receiving a clamping force.

The toner image bearing surface of the recording material 12 receives the heat of the heating element 1 via the fixing film 7 while passing through the fixing nip N in a state of being pressed and adhered to the fixing film surface. It melts and softens and adheres to the recording material 12 surface.

In the case of this embodiment, the recording material 12 is separated from the fixing film 7 when the recording material 12 has passed through the fixing nip N.

The recording material 12 separated from the fixing film 7 is guided by a guide 17 to reach a discharge roller (not shown). When the temperature becomes equal to or lower than the temperature, the recording material 12 is solidified, and the image-fixed recording material 12 is output. (2) First Glass Layer 100 As described above, the first glass layer 100 is a glass layer in which a ceramic filler is dispersed.

The glass component is lead borosilicate (PbO.B ₂
O ₃ .SiO ₂ ), zinc borosilicate (ZnO.B ₂ O ₃₎
· SiO _2), sodium borosilicate (Na ₂ O · B ₂
O ₃ · SiO ₂ ), calcium borosilicate (CaO · B ₂
O ₃ .SiO ₂ ) and bismuth borosilicate.

The ceramic filler is alumina (Al _20
3 ), zirconia (ZrO ₂ ), silicon nitride (Si ₃ N)
₄ ), titanium nitride (TiN), aluminum nitride (Al
N) and the like.

The size (particle size) of the filler is desirably less than 1/10 of the thickness of the glass coat layer.

The amount of the ceramic filler dispersed in the glass layer is generally 2 to 100 parts by weight based on 100 parts by weight of the glass content.

The thickness of the glass layer 100 is 30 μm or more and 50
The thickness was set to 0 μm or less.

Table 1 shows the thermal conductivity and dielectric strength of glass and various ceramics.

[0055]

[Table 1] As shown in Table 1, the ceramic filler has a significantly higher thermal conductivity than that of glass, and has the same or higher dielectric strength. By dispersing such a ceramic filler in glass, it is possible to increase the thermal conductivity of the glass. Further, the dielectric strength of the glass in which the ceramic filler is dispersed is equal to or higher than that of the glass in which the ceramic filler is not dispersed.

[0056] Therefore, the thickness of the first glass layer 100 by a ceramic <br/> click filler dispersion glass layer without thinning the glass layer in order to increase the heat transfer efficiency, i.e. the glass layer In a thickness setting that can ensure a sufficient withstand voltage, it is possible to sufficiently secure the heat transfer efficiency from the heating element 1 to the film, and to prevent the occurrence of image fixing failure due to insufficient heating of the recording material 12. Can be. Further, even if the film is broken and the pressure roller 10 comes into direct contact with the heating element 1, the glass layer 100 has a sufficient withstand voltage, so that electrical short-circuit and electric leakage are prevented.

When the ceramic filler dispersed in the first glass layer 100 is made of the same material as that of the substrate 2, for example, when the substrate 2 is alumina, the ceramic filler is also made of alumina. rate of it is possible to approximate the thermal expansion coefficient of 7 × 10 ^-6 ℃ ^-1 of the alumina substrate from thermal expansion 5 × 10 ^-6 ℃ ^-1 only glass, the thermal expansion coefficient difference between the substrate 2 and the glass layer 100 It is also possible to reduce or prevent the warpage of the heating element and the occurrence of cracks in the glass layer due to the generation of internal stress due to the above.

The ceramic filler was dispersed as described above .
The first glass layer 100 has a larger surface roughness than the glass layer without the ceramic filler, and has a lower lubricity with the inner surface of the film.

Therefore , the surface of the substrate 2 including the resistance heating element layer 3 is first coated with a first glass layer 100 in which a ceramic filler is dispersed, and a second glass layer 21 without a ceramic filler is further coated thereon. It was done.

The second glass layer 21 is the first glass layer 10
The first glass layer 100 may be thinner than 0, for example.
When the thickness is 0 μm, the thickness of the second glass layer 21 may be about 5 μm.

Since the second glass layer 21 is thin, the heat transfer efficiency of the entire glass layers 100 and 21 is better ensured by the first glass layer 100 in which the ceramic filler is dispersed, and does not substantially cause a deterioration.

The film 7 slides in contact with the smooth surface of the second glass layer 21 containing no ceramic filler, so that the smoothness between the heating element 1 and the film 7 is ensured. . <Embodiment 2 > (FIG. 3 ) From this embodiment, <Embodiment 5 > is an embodiment of the invention described in claims 3 to 5 .

[0063] The present embodiment is also a heating apparatus as an image heating and fixing apparatus, the overall configuration of the apparatus will be omitted described again because it is similar to the previously described Figure 1. FIG. 3 is an enlarged cross-sectional model diagram of a main part of the heating element.

The heating element 1 has an insulating material layer 101 mainly composed of ceramics and a resistance heating element layer 3, and the insulating material layer 101 is directly on the surface of the insulating material layer 101 with the insulating material layer 101 facing the film. The film 7 is made to slide in contact.

The insulating material layer 101 mainly composed of ceramic has a thickness of 1 mm or less having high heat resistance, high withstand voltage and good thermal conductivity as in the case of the substrate 2 of the heating element of the first embodiment.
Examples thereof include l ₂ O ₃ , Si ₃ N ₄ , AlN, and TiN. These ceramics have better thermal conductivity and dielectric strength than glass as shown in Table 1.

Since the thermal conductivity of the insulating layer 101 mainly composed of ceramic is much better than that of the glass layer, the efficiency of heat transfer from the heating element 1 to the film 7 can be sufficiently secured without reducing the thickness. Insufficient image fixing due to insufficient heating of the material 12 can be prevented, and a sufficient withstand voltage can be secured.

Therefore, the film 7 is torn and the pressure roller 1
Even if 0 directly contacts the heating element 1, the pressure roller 10 contacts the surface of the insulating layer 101 mainly composed of ceramic of the heating element 1, and the resistance heating element layer 3 exists on the contact surface. In addition, since the insulation withstand voltage of the insulating material layer 101 is sufficient, no electrical short-circuit or electric leakage trouble occurs.

In the present embodiment, since there is no glass coat layer different from the insulating material layer 101, troubles such as warpage of the heating element caused by a difference in thermal expansion between the insulating material layer 101 and such a glass coat layer. Does not occur.

<Embodiment 3 > (FIG. 4 ) The insulating layer 101 mainly composed of ceramics of Embodiment 2 described above.
The surface roughness is higher than that of the surface of the glass layer due to holes and the like formed when gas is released at the time of firing at a high temperature of 1000 ° C. or more, and the lubricity with the inner surface of the film is lower than that of the glass layer.

The present embodiment improves this point.
As shown in FIG. 4 , the insulating layer 101 mainly composed of ceramic has a film contact sliding surface coated with a glass layer 21.

The glass layer 21 may be thin,
It can be about 10 μm. Since the glass layer 21 is thin, the efficiency of heat transfer from the heater 1 to the film 7 is sufficiently ensured by the insulating layer 101 mainly composed of ceramic, and the presence of the glass layer 21 does not substantially deteriorate.

Since the film 7 slides in contact with the smooth surface of the glass layer 21, the lubricity between the heating element 1 and the film 7 is ensured.

Since the glass layer 21 is thin, the insulating layer 1
The internal stress generated in the heating element 1 due to the difference in thermal expansion between the heating element 1 and the glass layer 21 is small, and the heating element 1 does not substantially warp or crack the glass layer.

The glass layer 21 can be the ceramic filler-dispersed glass 100 of the first embodiment, or a two-layer structure 100 or 21 as in the second embodiment.

<Embodiment 4 > (FIG. 5 ) In this embodiment, the heating element 1 is mainly composed of a ceramic substrate 102, a resistance heating element layer 3 provided on the surface of the substrate, and a ceramic coated thereon. The film 7 is made to contact and slide directly on the surface of the insulating material layer 101 with the insulating material layer 101 side facing the film.

The thickness of the ceramic substrate 102 is 1 mm or less, and the insulating material layer 101 is coated with a thickness of 50 μm to 200 μm.

In this case, since the overall strength of the heating element 1 is maintained by the ceramic substrate 102, the thickness of the insulating material layer 101 that directly contacts and slides on the film 7 is smaller than in the second and third embodiments. As a result, the efficiency of heat transfer from the heater 1 to the film 7 can be improved.

The insulating material layer 101 may be formed by attaching a thin plate to the surface of the substrate 102 including the resistance heating element layer 3 instead of coating.

It is desirable to select the same material ceramic for the substrate 102 and the insulating material layer 101 in order to alleviate and prevent the occurrence of warpage or the like of the heater 1 due to the difference in thermal expansion coefficient between the two.

<Embodiment 5 > (FIG. 6 ) In the present embodiment, the same purpose as in the embodiment 4 is applied to the surface of the insulating material layer 101 mainly made of ceramic which is the contact sliding surface of the film in the embodiment 5. Thin glass coat layer 2
1 to improve the lubricity between the heating element 1 and the film 7.

[0081]

As described above, according to the present invention, in the film heating type heating apparatus and the heating element , the thickness of the glass layer as the insulating material layer of the heating element is not reduced, that is, the thickness of the glass layer is sufficient. In a thickness setting that can ensure a high withstand voltage, the heat transfer efficiency from the heating element to the film can be ensured well, and the heating element warpage caused by the difference in the coefficient of thermal expansion between the heater substrate and the glass layer can be improved. Generation of cracks in the glass layer can also be prevented.

Further, even if the presence of the glass layer as the insulating material layer is unnecessary, or if the glass layer is present, it is possible to prevent the occurrence of troubles due to the presence of the glass layer.

[Brief description of the drawings]

FIG. 1 shows a heating device (image heating constant ) according to a first embodiment.
Schematic diagram of the

FIG. 2 is an enlarged cross-sectional model diagram showing a configuration of a heating body of the apparatus.

FIG. 3 is an enlarged cross-sectional model diagram showing a configuration of a heating element of the second embodiment apparatus.

FIG. 4 is an enlarged cross-sectional model diagram showing a configuration of a heating element of the apparatus according to the third embodiment.

FIG. 5 is an enlarged cross-sectional model diagram showing a configuration of a heating element of the fourth embodiment apparatus.

FIG. 6 is an enlarged cross-sectional model diagram showing a configuration of a heating body of the fifth embodiment apparatus.

FIG. 7 shows a main part of a film heating type heating device (heating element).
Enlarged cross-sectional model diagram showing the configuration

[Explanation of symbols]

A Generic Symbol for Image Heating and Fixing Device 1.20 Generic Symbol for Heating Element 2 Heater Substrate 3 Resistance Heating Element Layer 6 Temperature Sensing Element 7 Fixing Film 8 Drive Roller 9 Follower Roller 10 Pressure Roller 11 Toner Image 12 Recording Material 21 Glass Layer (First glass layer) 100 Ceramic filler dispersed glass layer (second glass)
Layer 101 101 insulating material layer mainly composed of ceramic 102 ceramic substrate

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Daizo Fukuzawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yoji Tomoyuki 3-30-2 Shimomaruko, Ota-ku, Tokyo (56) References JP-A-3-25478 (JP, A) JP-A-2-242580 (JP, A) JP-A-59-47993 (JP, U) (58) Fields investigated ( Int.Cl. ⁷ , DB name) G03G 15/20 H05B 3/20-3/38

Claims (5)

(57) [Claims] A heating element having a heating element provided on a substrate;
A film that slides with the heating element;
The image on the recording material by the heat from the heating element through the
In a heating device for heating, the heating element is a first glass layer provided on the heating element.
And the film provided on the first glass layer,
A second glass layer in contact with the first glass layer
Has a ceramic filler dispersed therein and said second glass layer is
A heating device characterized by not containing a ceramic filler . 2. A substrate and a heating element provided on the substrate
And a first glass layer provided on the heating element; and a first glass layer provided on the heating element.
Second glass as a sliding layer provided on the glass layer of
And the first glass layer comprises a ceramic filler.
Is dispersed, and the second glass layer contains a ceramic filler.
A heating element characterized by not being included. 3. A recording medium comprising: a heating element provided with a heating element which generates heat by energization on a ceramic substrate; and a film sliding on the heating element, wherein recording is performed by heat from the heating element via the film. A heating device for heating an image on a material, wherein the heating element is in contact with the film on a surface of the ceramic substrate opposite to a surface on which the heating element is provided. 4. A heating apparatus according to claim 3 wherein the heating body is characterized by having a sliding layer on the surface of the film side of the ceramic substrate. A ceramic substrate [5 claim ## and emitting heat body, the sliding layer
When, in the heating body having said heating element is coated on the surface of the ceramic substrate, wherein
Heating body sliding layer and the heating element is provided a surface of the ceramic substrate, characterized that you have been coated on the opposite side.