JPH11212389A - Fixing roll and fixing device for electrophotography - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing roll capable of making heat capacity of the fixing roll reduced by making the thickness of the roll thin, while strengthening the mechanical strength, and a fixing device capable of drastically shortening the warp-up, saving the energy, and preventing an offset. SOLUTION: This roll is provided with releasing layer 7 consisting of fluorine- containing resign and or fluoro-rubber, at least, on a periphery of a hollow carbon fiber-reinforced metal core roll 1 constituted by integrating matrix metal and a fibrous sheet of graphitized carbon fiber. The matrix metal is preferably composed of aluminum or iron, and the elastic layer 3 consisting of silicone rubber is disposed between the surface on the carbon fiber-reinforced metal core roll 1 and releasing layer 7. This fixing roll for electrophotography (carbon fiber-reinforced metal core roll 1), for forming a fixing nip area where the unfixed toner image is allowed to pass there through, is adopted by at least, either one of the heating roller or the pressure roller of the fixing device provided with either one of the heating roller and the pressure roller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing roll used in a fixing device of an image forming apparatus such as an electrophotographic copying machine and an electrophotographic printer using a powder toner. Further, the present invention relates to a fixing device, and more particularly to a fixing device capable of reducing the size of the device and significantly shortening a warm-up time and saving energy.

[0002]

2. Description of the Related Art Conventionally, in a copying machine or the like utilizing an electrophotographic process, it is necessary to fix an unfixed toner image formed on a recording sheet into a permanent image. A pressure fixing method and a heat fixing method are known. However, the solvent fixing method has the drawbacks that solvent vapor is emitted, and there are many odors and hygiene problems.On the other hand, the pressure fixing method has poor fixability as compared with other fixing methods and is pressure sensitive. However, these toners have the disadvantage that they are expensive and have not been widely put to practical use. For this reason, in order to fix an unfixed toner image, a heat fixing method of melting the toner by heating and fusing the toner on a recording sheet is widely used.

[0003] In this heat fixing device, a fixing roll having a heater amplifier inside a cylindrical core metal and a heat-resistant release layer formed on the outer peripheral surface thereof, and a cylindrical presser arranged in pressure contact with the fixing roll. A heat-fixing roll type is known, which comprises a pressure roll having a heat-resistant elastic layer formed on the outer peripheral surface of a cored bar, and a sheet on which an unfixed toner image is formed is inserted between these rolls to perform fixing. This method has higher thermal efficiency compared to other heat fixing methods such as hot air fixing method and oven fixing method, so it has low power, high speed, and less risk of fire due to paper jam. Is currently the most widely used.

In the conventional fixing roll type fixing device, the time required for raising the surface temperature of the fixing roll from room temperature to a predetermined set temperature (hereinafter referred to as warm-up time) is 1 to 10 minutes. I needed a long time. The warm-up time is simply determined by the relationship between the heat capacity of the roll and the input power. That is, if the heat capacity of the roll is small and the input power is large, the warm-up time can be shortened. However, the roll heat capacity is limited by the roll rigidity, and the input power is limited by the power consumption of the machine. Therefore, in general, the power that can be supplied only for fixing is about 300 W to 1200 W, and in order to shorten the warm-up in this range, it is most effective to reduce the heat capacity of the roll. However, as the roll diameter or the thickness of the roll core is reduced to reduce the heat capacity of the roll, the strength of the roll tends to decrease. Incidentally, the roll heat capacity is proportional to the square of the roll diameter, while the roll rigidity is proportional to the fourth power of the roll diameter. For this reason, when the roll diameter becomes smaller than a certain roll diameter, the roll rigidity rapidly decreases, and the roll is largely bent, so that a load required for fixing cannot be obtained.

[0005] In order to solve these problems, various roll strength reinforcing techniques and various roll radius correction techniques have been proposed. For example, JP-A-59-30571 and JP-A-59-128665 disclose the inside of a sleeve composed of a thin plate having a small heat capacity.
A roll strength reinforcing technique has been proposed in which one or more inner supports for supporting a sleeve via a thermal insulator are arranged between both supports so as to have flexibility. In the gazette, a disk is fitted as a fulcrum member on a pressing shaft, and this pressing shaft is put into a pair of upper and lower hollow pipe rolls, a load is applied to both ends, and the pressing portion shaft is bent, and the pressurizing shaft is bent. A roll radius correction technique for obtaining a uniform pressure has been proposed. In addition, JP-A-4-44074, JP-A-4-44074
44075 and JP-A-4-372974 disclose a technique for arranging a heating and pressing member fixed inside an endless film or a belt to obtain a uniform heating and pressing portion. No. 43775 discloses a heat transfer plate in which a pressure member is pressed with a constant pressure against a hollow heat roll containing a resistance heating element therein, and the resistance heating element has an arc-shaped convex portion corresponding to the inner peripheral surface of the heat roll. It is disclosed that the heat is heated by a heat roll via a heat transfer plate. Since none of these techniques improve the strength of the metal roll itself, there is a short life problem due to metal fatigue in the long term.

[0006] On the other hand, there are disclosed rolls and fixing devices in which the mechanical strength of the roll is increased by reinforcing fibers such as carbon fiber. For example, Japanese Unexamined Utility Model Publication No. 61-024765 discloses a fixing device in which an unfixed image on a recording sheet is pressure-fixed in a nip portion between a pair of rolls rotating in contact with each other. A technique having a fiber reinforced surface layer is disclosed, and the carbon fiber reinforced surface layer is obtained by dispersing and reinforcing carbon fibers in a resin matrix. However, the toner for pressure fixing used in this fixing device is a wax-based toner or a microcapsule toner in which a mixture of a liquid resin and oil at a temperature near normal temperature is covered with a resin layer that is solid at normal temperature. And other special toners, and are not generally used.

In Japanese Utility Model Publication No. 58-48684, a roll body having insulation and heat resistance and a carbon fiber are uniformly formed on the roll body in a certain direction using a polymer binder. A heat-fixing roll comprising a heating element and a release layer covering the heating element is disclosed. Since the heat fixing roll also has a reinforced resin layer, it is difficult to make the mechanical strength higher than that of the metal roll, and it is difficult to reduce the thickness of the fixing roll core even when used in the above-mentioned heat fixing device. Further, the thermal conductivity is lower than that of metal, and the heating time is not shortened.

Japanese Patent Application Laid-Open No. Hei 6-207614 discloses a roll made of carbon fiber reinforced resin having a resin film integrally formed on the surface thereof.
Fluorine / silicon-containing polymer obtained by copolymerizing a copolymerizable fluorine-containing monomer that can be baked and cured at a temperature below the next dislocation point (Tg) with a silicon macromonomer and other copolymerizable vinyl monomers Rolls made of carbon fiber reinforced resin having good ink releasability, wherein the rolls are formed integrally on the surface. Since the carbon fiber reinforced resinous roll also reinforces the resin layer, it is difficult to make the mechanical strength higher than that of the metal roll, and it is impossible to reduce the thickness of the fixing roll even when used in the above-described heating fixing device. In the above example, the resin is a roll reinforced with carbon fiber,
The heat resistance temperature of the resin itself is required, and the resin used is limited to a thermosetting heat-resistant resin and the like, and the production cost for integrating with the carbon fiber increases.

Japanese Patent Application Laid-Open No. 7-206241 discloses a roll in which a metal is reinforced by carbon fiber. The matrix pipe has a matrix metal reinforced by graphitized carbon fiber or a metal solid shaft. A fiber-reinforced metal roll having a coating layer formed of a material different from metal is disclosed. This fiber reinforced metal roll has the advantages that it is easy to achieve a mechanical strength higher than that of the metal core roll and that the heat resistance is sufficient. Therefore, when used in the above-described heat fixing device, the thickness of the fixing roll can be reduced, and the heating time can be shortened. However, since these rolls are used in contact rolls, transport rolls, nip rolls, and the like, which are used in industries such as high-speed printing machines and film coating machines, toner offset is likely to occur when used in the above-described heat fixing device.

As described above, in the prior art, the heat capacity of the fixing roll can be sufficiently reduced by reducing the thickness of the roll while increasing the mechanical strength of the roll material, and the occurrence of offset can be prevented. There was no roll.

[0011]

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, a first object of the present invention is to provide a roll having a thickness equal to or greater than that of a conventional aluminum or iron metal roll even if the roll thickness is reduced. An object of the present invention is to provide a fixing roll for electrophotography which can have mechanical strength and can prevent toner offset. A second object of the present invention is to form a fixing nip area through which an unfixed toner image passes.
An object of the present invention is to provide an electrophotographic fixing device having at least one of a heating roll and a pressure roll, in which the heat capacity of the fixing roll is reduced and the heating time is shortened, and the power consumption is reduced, as compared with the related art.

[0012]

The fixing roll for electrophotography according to the present invention comprises at least the outermost surface of a hollow carbon fiber reinforced metal core roll formed integrally with a matrix metal and a woven sheet of graphitized carbon fibers. A fixing roller for electrophotography, provided with a release layer made of a fluorine-containing resin and / or a fluorine rubber. Further, in the fixing device according to the present invention, in order to form a fixing nip area through which an unfixed toner image passes, in a fixing device including at least one of a heating roll and a pressure roll, at least one of a heating roll and a pressure roll is used. One of them has the structure of the above-mentioned fixing roll for electrophotography.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described. The fixing roll of the present invention is a mold release mold comprising a hollow graphitized carbon fiber reinforced metal core roll formed integrally with a metal and a woven sheet of carbon fiber, and a fluorine-containing resin and / or fluorine rubber as at least an outer surface coating layer. And layers.

The graphitized carbon fiber reinforced metal core roll is formed by winding a woven sheet of graphitized carbon fiber around a core roll such as carbon steel and integrating the same by a known method. For example, a high-pressure casting method in which a molten metal matrix mold is cast at a high pressure, or a squeeze casting method in which a woven sheet of graphitized carbon fiber is put in the mold and then poured into the metal matrix mold melted at a high pressure. A woven sheet of graphitized carbon fiber is wound around a core or a core roll, and a woven sheet of metal and graphitized carbon fiber is integrally formed by a low-pressure plasma deposition method in which a vapor phase metal is deposited on this sheet. can do. Here, aluminum, aluminum alloy, iron, copper, magnesium or magnesium alloy, titanium or titanium alloy, etc. can be used for the metal matrix. Among these metals, iron and copper are preferably used when emphasis is placed on workability and heat resistance. Aluminum or an aluminum alloy having a relatively low melting point is preferable from the viewpoint of easy formation of a graphitized carbon fiber fabric, and an alloy of aluminum and titanium or magnesium, iron or the like is preferable from the viewpoint of increasing mechanical strength. Therefore, considering workability, cost, etc., aluminum, aluminum alloy, and iron are preferred.

Usually, graphitized carbon is used as the reinforcing fiber.
In addition to raw fiber, Roron, SiC, Al_TwoO _3,Be, W, etc.
However, if the outer diameter of the fiber is large, the metal
In the present invention, since the thickness becomes uneven,
Graphitized carbon fibers with a small diameter are used. Graphitized carbon fiber
Weaving woven sheets are carbonized and fired at high temperature (2000 ° C).
Graphitized carbon fiber with a diameter of 5 to 10 μm from which impurities have been removed
Knit 1000 to 20000 yarns into a woven fabric
Those in the form of a sheet are preferred. Graphitized carbon fiber fabric
Sheets are woven in units of 1000 for ease of molding work
Is good. Specifically, Pyrofil manufactured by Mitsubishi Rayon Co., Ltd.
A woven sheet such as a trading card manufactured by Re can be used. Fibrous
Directionality is not always important, in other words, carbon fiber
It is important that they are aligned in the same direction. Therefore, carbon fiber
Even if the direction of the fiber is perpendicular to the core roll,
Alternatively, the direction may be skewed.

The weight ratio of the graphitized carbon fibers in the graphitized carbon fiber reinforced metal roll is preferably from 10 to 70% by weight, more preferably from 30 to 50% by weight. If the weight ratio is less than 10 wt%, the mechanical strength cannot be increased, and the weight ratio is 70%.
If the content exceeds wt%, the metal matrix binding between the carbon fibers is reduced, the binding force between the carbon fibers is reduced, and the rolls are liable to breakage such as cracks due to mechanical impact. The graphitized carbon fiber reinforced metal roll produced by the method described above has a surface close to the finished size and has a roundness of the outer diameter. The same processing is performed to obtain the roundness of. In this way, a graphitized carbon fiber reinforced metal roll is produced to form a fixing core roll.

At this time, since the carbon fiber is hard, the surface is smoothed by shaving the carbon fiber by processing. When the thickness of the core roll is as thin as 0.2 to 3.0 mm, a large load is applied to the roll by surface processing such as polishing. It is difficult because you can not.
The outer surface of the roll is further provided with a release layer with low surface energy, so there is not much need for smoothness.However, the inner surface of the roll at the flange joint at the end of the roll is made of carbon fiber after processing to increase the strength of the flange joint. It is not preferable that there remain no smoothness. Therefore, it is preferable that the woven sheet of carbon fiber is formed integrally with the metal at the end of the hollow roll except for the flange joining portion, and that the flange joining portion is made of only the metal because the inner surface processing becomes easy.

The release layer formed on the surface of the hollow carbon fiber reinforced metal core roll is made of a fluorine-containing resin and / or fluorine. This release layer can be formed by applying various known methods such as spray coating, coating, and tubing after applying a heat-resistant primer to the surface of the carbon fiber reinforced metal core roll. The surface energy of the release layer is about 25 dyn /
cm or less is desirable, and it is reported that carbon fluoride, perfluorocarbon and the like are 6 dyn / cm, and the release layer may contain these carbons. When forming a fluorine-containing resin layer, the thickness is preferably thin so as not to deteriorate the thermal conductivity, and even if abrasion or scratches due to long-term use occur, the fluorine-containing resin layer remains and the surface of the fixing core roll is exposed. It is preferable that the thickness be large in order not to become large. From these points, the release layer is usually 10 to 40
It is preferably about μm.

The fluorine-containing resin layer is made of tetrafluoroethylene resin (PTFE resin), tetrafluoroethylene-perfluoroalkoxyethylene copolymer (PFA resin), tetrafluoroethylene-6-fluoroethylenepropylene copolymer (PFE resin), which is mainly composed of fluorocarbon resin with excellent mold release properties and heat resistance such as amorphous cyclic fluorocarbon resin.For these resins, fluorocarbon particles, carbon particles, A mixture of inorganic particles such as silica particles can also be used. These fluororesin mixtures are diluted by electrostatic coating or special solvent and coated by spray coating, roll coating, dipping, spinning, etc.
Use after baking hardening. Alternatively, heat-shrink a heat-shrinkable tetrafluoroethylene-perfluoroalkoxyethylene copolymer (PFA resin) tube to obtain a fixing roll having a fluorine-containing resin layer formed on the surface of a carbon fiber reinforced metal core roll. Can also.

When fluororubber is used, general-purpose ones can be used. As the fluorine rubber, vinylidene fluoride rubber, ethylene tetrafluoride / propylene rubber, ethylene tetrafluoride / perfluoromethyl vinyl ether rubber,
Phosphazene rubber, fluoropolyether and the like and other fluorine rubbers can be used. These may be used alone or in combination of two or more. Various kinds of inorganic or organic fillers can be used for these rubbers.

As the inorganic filler, carbon black,
Titanium oxide, silica, silicon carbide, talc, mica, kaolin, iron oxide, calcium carbonate, calcium silicate,
Examples include magnesium oxide, graphite, silicon nitride, boron nitride, iron oxide, aluminum oxide, magnesium carbonate, and the like. As the organic filler, polyimide, polyamide imide, polyether sulfone, polyphenylene sulfide, or the like can be used. In addition, a silicone rubber, a fluorine rubber, a fluorosilicone rubber, or the like can be formed as an elastic layer under the release layer.

FIG. 1 is a sectional view showing a preferred embodiment of the fixing roll for electrophotography according to the present invention. In the drawing, 1 is a carbon fiber reinforced aluminum core roll, 2 is a carbon fiber reinforced aluminum layer, and 3 is aluminum. Reference numeral 4 denotes a heating source, 5 denotes a flange, 6 denotes a silicone rubber layer, and 7 denotes a fluoro rubber release layer.

Next, a preferred embodiment of an electrophotographic fixing device of the present invention will be described with reference to the drawings. FIG. 2 is a schematic configuration diagram showing a preferred embodiment of the electrophotographic fixing device of the present invention. This fixing device is suitable for obtaining a color image, and is mainly composed of a heating roll 21 configured as the above-described fixing roll for electrophotography, and a pressure roll 25 pressed against the heating roll 21. Therefore, the fixing roll 21 is provided with the heater lamp 29 inside the hollow carbon fiber reinforced metal core roll 22 in which the matrix metal and the woven sheet of the graphitized carbon fiber are integrally formed. Elastic layer 23a on the surface and release layer 23 having heat resistance and low surface energy
b is formed. The pressure roll 25 has a heat-resistant elastic layer 27 formed on the outer peripheral surface of a cylindrical metal core 26, and a surface coating layer 28 is formed on the heat-resistant elastic layer 27. In FIG. 1, reference numeral 30 denotes a heating source, 31 denotes a release agent application device, 32 denotes an inlet chute, and 33 denotes an outlet chute.

In this fixing device, a fixing nip area is formed by the heating roll 21 and the pressure roll 25. On this occasion,
The pressure of the heating roll 21 and the pressure roll 25 is 1 to 15
Kg / cm ^2, preferably by applying a 3 to 10 kg / cm ^2, those of the heat-fixing roll method in which the fixing is inserted a sheet 34 formed of the unfixed toner image 35, the sheet winds around the fixing roller For example, a separating claw for preventing the occurrence of the toner and a cleaning device for cleaning the offset toner adhered to the fixing roll may be provided. Further, the pressure roll 25 may be a roll having the same configuration as the heating roll.

FIG. 3 is a schematic configuration diagram showing another preferred embodiment of the fixing device of the present invention. This device is a fixing device suitable for obtaining a black and white image. In FIG.
41 is a heating roll, 42 is a pressure roll, 43 is an aluminum core roll, 44 is a silicone rubber elastic layer, 45 is a separation claw, 46 is a cleaning web, 47 is a temperature sensor,
48 denotes an unfixed toner image, and 49 denotes a sheet. In this fixing device, the heating roll 41 preferably has a certain degree of hardness on the roll surface in order to fix an elastic toner image, and therefore, an elastic layer made of silicone rubber is not necessarily required. Therefore, the heating roll 41 is a carbon fiber reinforced metal core roll 41.
a roll structure having a release layer 41 b made of a fluorine-based resin or fluorine-based rubber on the outer peripheral surface may be used.
On the side, the aluminum core roll 43 may have an elastic layer 44 made of silicone rubber or the like, or the carbon fiber reinforced metal core roll may have an elastic layer made of silicone rubber or the like on its outer peripheral surface.

FIG. 4 is a schematic structural view showing still another preferred embodiment of the fixing device of the present invention. In FIG. 4, 51 is a heating roll, 52 is a pressure roll, 53 is a tension control roll, 54 is a conveyor belt, and 55 is a heating lamp. The heating roll 51 has a roll configuration having an elastic layer 51b made of silicone rubber and a release layer 51c made of fluororesin or fluororubber on the outer peripheral surface of the carbon fiber reinforced metal core roll 51a.

FIG. 5 is a schematic structural view showing still another preferred embodiment of the fixing device of the present invention, and shows a thermal transfer belt type fixing device. In FIG. 5, reference numeral 61 denotes a support having a heat-resistant belt made of polyimide or the like on which a low surface energy layer such as PFA is formed as a release layer. Reference numerals 62 and 65 denote pressure rolls. Reference numeral 63 denotes a pressing member which is located in the pressing roll 62 and has a low friction member 63a such as Teflon at the tip. 64 is a heating lamp, 67 is a core roll, 66 is a silicone rubber layer, 68 is a peeling nail, 69 is an inlet chute, 70 is unfixed toner, and 71 is paper. The pressure roll 62
The outer surface has a rubber layer made of fluorine rubber having a thickness of 20 μm on the surface of the carbon fiber reinforced core roll, and the pressure roll 65 has an elastic layer made of a silicone rubber layer on the surface of the carbon fiber reinforced core roll.

FIG. 6 is a schematic structural view showing still another preferred embodiment of the fixing device of the present invention, and shows a roll type fixing device having an intermediate thickness between a belt and a roll. Reference numerals 82 and 86 denote carbon fiber reinforced core rolls, the release layers 8 of which surfaces are coated with fluoro rubber, fluoro resin, or the like.
1, 85 are formed. Reference numerals 83 and 87 denote pressing members 83a and 87a made of a low-friction member such as Teflon, which are located at the distal end. 84 is a heating lamp, 88 is a peeling nail,
89 is an inlet squirt, 90 is unfixed toner, 9
1 is a sheet.

(Function) Since the fixing roll of the present invention is formed by a carbon fiber reinforced metal core roll, the mechanical strength such as bending elastic modulus is improved as compared with the aluminum or iron roll used in the conventional heat fixing device. As a result, even if the load applied to both ends of the fixing roll is the same, the bending of the roll in the axial direction and the distortion of the roll in the circumferential direction are reduced, so that the thickness can be set to be small. By reducing the thickness, the heat capacity of the fixing roll can be reduced, and the warm-up heating time can be shortened. As a result, power consumption can be reduced as compared with the conventional heat fixing device.

The heat fixing apparatus using the fixing roll according to the present invention is effective because the amount of reduction in power consumption is particularly large in a high-speed image forming apparatus. This depends on the circumstances described below. The mechanical strength, such as the required bending elasticity, of the fixing roll depends on the diameter of the fixing roll and the load applied to the fixing roll. In a typical heat fixing device, the fixing roll diameter is 15 to 100 mm, and the load applied to the fixing roll is 3 to 300 k.
gf. These values greatly vary depending on the copying speed of the image forming apparatus, and also slightly vary depending on the maximum usable paper width, toner material, and the like. Generally, as the speed of the image forming apparatus increases, the diameter of the fixing roll is increased so that the dwell time, which is the transit time of the fixing nip portion of the paper, is not so short, and the force for adhering toner to the paper is increased. Therefore, it is necessary to increase the load applied to the fixing roll and increase the pressure at the fixing nip. When the diameter of the fixing roll or the load applied to the fixing roll increases, it is difficult to reduce the thickness of the roll unless the mechanical strength such as bending elasticity required for the fixing core roll is increased. In addition, the warm-up heating time for setting the fixing roll surface at a set temperature at which the fixing material can be fixed is determined by the thickness of the core roll if the same material is used, so the thinner the core roll, the shorter the warm-up heating time. Come. Also in the case of the carbon fiber reinforced metal roll of the present invention, since it does not change much compared to the thermal conductivity of the matrix metal, by reducing the thickness of the core roll,
Warm-up heating time can be shortened.

If the speed of the image forming apparatus is low,
For example, if the speed is about 80 mm / s or less, the fixing roll diameter can be set to 15 to 20 mm, the load can be set to 10 kgf or less, and the pressure at the fixing nip can be set to about 1 kgf / cm ² . In this case, the fixing roll is a conventional aluminum roll with a core roll thickness of 1.5 m.
m or less, the temperature can be set to a value that allows fixing with a waiting time of about 60 seconds or less, and power consumption during the warm-up heating time is small.

However, when the speed of the image forming apparatus is higher than 300 mm / s, the load applied to the fixing roll is about 100 to 30.
At 0 kgf, the pressure is 5 to 10 kgf /
It is set to a range of about cm ² . In this case, the diameter of the fixing core roll needs to be about 30 mm or more, and if it is a conventional aluminum roll, it must be set to a thickness of about 4 mm or more.
It takes 4 minutes or more to warm up. For this reason, even when normal image formation is not performed on a high-speed machine,
The fixing roll is heated to a predetermined temperature and set to the standby mode. For this reason, in a high-speed machine, extra power is consumed even when normal image formation is not performed.

Therefore, the heat fixing device using the fixing roll of the present invention is effective because the amount of reduction in power consumption is particularly large in a high-speed image forming apparatus. Further, since a low surface energy release layer having excellent releasability of a toner comprising a fluorine-containing resin and / or a fluororubber is provided on the surface of the fixing roll of the present invention, a conventional heat fixing toner can be used. No offset occurs.

[0034]

Embodiment 1 Next, an embodiment of the present invention will be described. (1) Preparation of a core roll A method of manufacturing a core roll will be described with reference to FIG. The method of manufacturing the fixing roll is as follows: First, 6,000 carbon fibers of 5 to 7 microns in diameter are surrounded around a carbon steel core (outer diameter 37.0 mm, length 400 mm).
1 A ribbon-shaped carbon fiber sheet (CO6644B,
Plain weave, trading card, manufactured by Toray Co., Ltd.)
Avoid the inner aluminum layer 3) and spirally wind it 10 times (approximately 2mm thick) in the circumferential direction.
, Set in a mold with a length of 400mm, inject and pressurize the molten aluminum, cast 44.0mm in outer diameter and 40mm in length.
A solid axis of 0mm was created. The fiber content was calculated to be about 33% by weight. After that, the above core was de-centered, the inner diameter was 37.0 mm,
A sleeve of carbon fiber reinforced aluminum core 1 having an outer diameter of 44.05 mm, a thickness of 3.5 mm, and a length of 370 mm was prepared. A portion of the aluminum layer 3 having both ends of 15 mm was cut to obtain a roundness of the inner diameter, and this portion was mirror-finished with powdered carbon steel. After this,
A flange 5 made of carbon steel S45C having a thickness of 5 mm and an outer diameter of 37.0 mm was bonded to both ends of the core roll with an adhesive to prepare a carbon fiber reinforced aluminum core roll.

(2) Comparison of Strength A reinforced core roll was compared with an unreinforced aluminum core roll of the same material and of the same dimensions in a bending rigidity test. Flexural modulus of unreinforced aluminum core roll is 5000kg / m
m ² , the specific elasticity was 1.8 × 10 ³ mm, whereas the reinforced core roll had a flexural modulus of 27,000 Kg / mm ² and a specific elasticity of 10
× 10 ³ mm, indicating that both the flexural modulus and the specific elasticity were 5 times.

(3) Preparation of Fixing Roll After that, the carbon fiber reinforced hollow roll is polished with a carbon steel brush roll so as to have an outer diameter of 44.0 mm, the roundness of the outer diameter is obtained, and the silicone rubber is rolled. Ready to coat the stratum. Silicone rubber as the elastic layer has a rubber hardness of 55
HTV silicone rubber was coated to a thickness of 3 mm to obtain a base roll. Furthermore, a primer for fluoro rubber is applied to the surface, and a binary peroxide fluoro rubber G-
802 (manufactured by Daikin Industries, Ltd.) was formed to a thickness of 40 μm, and a heating roll having an elastic layer made of silicone rubber and a release layer made of fluorine rubber was prepared. The surface is polished and polished,
A fixing roll having an outer diameter of about 50.0 mm, an inner diameter of 44 mm, and a length of 400 mm was obtained.

(4) Preparation of pressure roll A pressure roll was prepared in exactly the same manner as the fixing roll except that the thickness of the silicone rubber elastic layer on the core roll was 1 mm. (5) Measurement of warming-up time by actual fixing device and copy test The fixing roll and the pressure roll were installed in the fixing device shown in FIG. 2, and a warm-up time measurement and a copy test were performed. The copy discharge speed is 150mm / sec, the load is 130Kgf, the nip width created by the two rolls is 6.0mm,
The electric power of the halogen lamp heating means of the fixing roll and the pressure roll was 650 W and 525 W, and the set temperature was 155 ° C. First, the warm-up time from room temperature 20 ° C to the set temperature was measured to be 310 seconds, which was greatly reduced. Even when the nip was set to 6.0 mm, no abnormal dent or nip shape was observed at the end, and the toner could be fixed without any problem even when the unfixed toner image was actually conveyed.

Comparative Example 1 (1) Preparation of Core Roll A core roll having the same aluminum material and the same outer diameter as in Example 1 but with a different thickness was prepared. (2) Comparison of strength A non-reinforced aluminum core roll and a reinforced aluminum core roll having different thicknesses were subjected to a comparative test by a bending rigidity test. 7.5mm thick
The unreinforced core roll had a flexural modulus of 21,000 kg / mm ² and a specific elasticity of 7.8 × 10 ³ mm, whereas the 3.5 mm thick reinforced aluminum core roll had a flexural modulus of 27,000 kg / mm ² and a specific elasticity of Is 10 × 10 ³ mm, and both flexural modulus and specific elasticity are about 1.
It turns out that it has tripled. (3) Preparation of a fixing roll and a pressure roll Just as in Example 1, a silicone rubber elastic layer and a fluorine rubber release layer were sequentially formed on the surface of the core roll,
A fixing roll and a pressure roll were prepared. (5) Measurement of warming-up time by actual fixing device and copy test The fixing roll and the pressure roll were installed in the fixing device shown in FIG. 2, and a warm-up time measurement and a copy test were performed. Various conditions were the same as in Example 1. Even when the nip was set to 6.0 mm, no abnormal dent or nip shape was observed at the end, and even if the unfixed toner image was actually conveyed, it could be fixed without any problem. However, the warm-up time was measured at 420 seconds, which was much longer.

Next, in the fixing device having the structure shown in FIG. 2, the heating roll is provided on the core with Si rubber (3
mm) layer, and free oil on the outer surface
%, And a roll (1) on which an HTV-based Si rubber containing 50% was formed and a heating roll were placed on the core at an HTV hardness of 60 °.
And a roll (2) in which a fluorine rubber was formed on the outer surface thereof at a thickness of 40 μm, and a wear resistance comparison test was performed. The m / c speed was adjusted to 100 mm / sec, and the chip width was adjusted to 6.0 mm each. The toner was Acrylic cyan toner with a toner amount of 0.7 mg / cm ² , and the paper was manufactured by Fuji Xerox Co., Ltd. J paper was used. The set temperature was set to 160 ° C., the paper was fed vertically, and a portion where the paper touched and a portion where the paper did not touch were formed in the width of the roll, and the degree of wear of each portion was measured. The release agent was supplied as an Acolor fuser oil in an amount of 10 μl / A4 copy. As a result, 2
The level difference between the sheet passing portion and the non-sheet passing portion on the roll surface after 00000 copies (due to the abrasion of the sheet) was as follows.

[0040]

[Table 1] As shown in Table 1, the abrasion resistance of a roll of fluoro rubber on the outer surface is higher than that of a roll of Si rubber on the outer surface.

[0041]

As described above, a fixing roll provided with a release layer made of a fluorine-containing resin and / or a fluorine rubber on at least the outer surface of the carbon fiber reinforced metal core roll of the present invention, and a fixing device provided with the same. Since the strength can be maintained while reducing the thickness of the core roll and reducing the heat capacity, energy consumption required for warm-up heating can be reduced, and offset can be prevented. Further, the present invention is also applicable to various fixing devices by combining both a roll and a belt.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a preferred embodiment of a fixing roll of the present invention.

FIG. 2 is a schematic configuration diagram showing a preferred embodiment of a fixing device of the present invention.

FIG. 3 is a schematic configuration diagram showing another preferred embodiment of the fixing device of the present invention.

FIG. 4 is a schematic configuration diagram showing still another preferred embodiment of the fixing device of the present invention.

FIG. 5 is a schematic configuration diagram showing still another preferred embodiment of the fixing device of the present invention.

FIG. 6 is a schematic configuration diagram showing still another preferred embodiment of the fixing device of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 carbon fiber reinforced aluminum core roll 2 silicone rubber elastic layer 3 aluminum layer 4 heating source 5 flange 6 carbon fiber reinforced aluminum layer 7 fluoro rubber release layer 21 heating roll 25 pressure roll 41 heating roll 42 pressure roll 51 heating roll 52 Pressing roll 54 Conveying belt 61 Heat-resistant belt 62 Pressing roll 63 Pressing member 65 Pressing roll 81 Release layer 82 Carbon fiber reinforced core roll 83 Pressing member 85 Release layer 86 Carbon fiber reinforced core roll 87 Pressing member

Claims (8)

[Claims] 1. A mold release layer comprising a fluorine-containing resin and / or a fluororubber is provided on at least the outer surface of a hollow carbon fiber reinforced metal core roll integrally formed with a matrix metal and a woven sheet of graphitized carbon fibers. A fixing roll for electrophotography, wherein the fixing roll is provided. 2. The fixing roll for electrophotography according to claim 1, wherein the matrix metal is aluminum or iron. 3. The woven sheet of graphitized carbon fibers is formed integrally with metal at a portion other than the flange joining portion at the end of the hollow roll. Fixing roll for electrophotography. 4. The fixing roll for electrophotography according to claim 1, further comprising an elastic layer made of silicone rubber between the surface of the carbon fiber reinforced metal core roll and the release layer. 5. A fixing device provided with at least one of a heating roll and a pressure roll for forming a fixing nip area through which an unfixed toner image passes, wherein at least one of the heating roll and the pressure roll is provided. A fixing device comprising the fixing roll for electrophotography according to claim 4. 6. A fixing roll pair in which the heating roll and the pressure roll are pressed against each other, and an unfixed toner image is passed through a fixing nip area formed by a contact portion between the two rolls.
The fixing device according to claim 5, wherein at least a heating roll of the two rolls comprises the fixing roll for electrophotography according to claim 1. 7. A nip region formed by the heating roll, the pressing belt that presses the heating roll, and the pressing roll that presses the pressing belt from behind. 5. A heating and pressurizing type fixing device in which an unfixed toner image is passed through the fixing device and fixed by heat and pressure.
6. The fixing device according to claim 5, comprising a fixing roll for electrophotography according to claim 5. 8. A heating belt having at least a surface having heat resistance and releasability, a pressing member for pressing the heating belt from the inside and a pressing roll at a position opposing the pressing member, wherein the heating belt is provided. 5. A heating and pressing type fixing device in which an unfixed toner image passes through a nip area formed by the pressing member and the pressing roll and is fixed by heat and pressure, wherein the pressing roll is used.
6. The fixing device according to claim 5, comprising a fixing roll for electrophotography according to claim 5.