JP2007101736A - Fixing roller, method for manufacturing fixing roller, fixing device, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing roller capable of improving the thermal conductivity in the thickness direction of an elastic layer and shortening the startup time of a fixing device, a method for manufacturing the fixing roller, a fixing device equipped with such a fixing roller, and to provide an image forming apparatus. <P>SOLUTION: The fixing roller (the fixing roller of the present invention) 21 has a roller body 210 and an elastic layer 214 provided on an outer peripheral side of the roller body 210. The elastic layer 214 includes a fibrous carbon-based substance 212, aligned in its thickness direction and an elastic material 213 fixing the fibrous carbon-based substance 212. The elastic material 213 preferably has silicone rubber as the principal component. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fixing roller, a method for manufacturing the fixing roller, a fixing device, and an image forming apparatus.

An image forming apparatus such as a printer, a copy machine, a facsimile machine, etc., heats and presses a recording material (recording medium) that carries a toner image formed with toner in an unfixed state, whereby the toner image is applied to a recording sheet. Some are provided with a fixing device for fixing.
As such a fixing device, for example, a recording material on which a toner image is transferred is passed between a fixing roller having a built-in halogen heater (heating means) and a pressure roller, and heated by two rollers. In addition, a toner image is fixed on a recording material by pressurization (see, for example, Patent Document 1 (FIG. 1)).

Here, in the fixing roller (fixing roller and pressure roller) used in the fixing device described in Patent Document 1, one or two or more elastic layers are formed on the outer peripheral surface of the core metal (roller body). Configured. For this reason, the heater heats the elastic layer via the mandrel and heats the entire fixing roller.
The elastic layer contains a layer composed of silicone rubber. Since silicone rubber has low thermal conductivity (0.2 to 0.5 W / m · k), heating by the heater is started. Thereafter, there is a problem that it takes time to warm the entire fixing roller.

JP-A-5-32898

  It is an object of the present invention to improve a thermal conductivity in the thickness direction of an elastic layer and shorten a start-up time of a fixing device, a method for manufacturing such a fixing roller, and a fixing equipped with such a fixing roller An apparatus and an image forming apparatus are provided.

Such an object is achieved by the present invention described below.
The fixing roller of the present invention is a fixing roller having a roller body and an elastic layer provided on the outer peripheral side of the roller body,
The elastic layer includes a fibrous carbon-based material oriented in the thickness direction and an elastic material that fixes the fibrous carbon-based material.
Thereby, the thermal conductivity in the thickness direction of the elastic layer can be improved, and the start-up time of the fixing device can be shortened.

In the fixing roller of the present invention, the elastic material is preferably composed mainly of silicone rubber.
Silicone rubber is particularly preferable because it is excellent in heat resistance and excellent in elasticity (flexibility). Moreover, it is also preferable because it is easy to form an elastic layer using LIM molding.

In the fixing roller of the present invention, the content of the fibrous carbonaceous material in the elastic layer is preferably 20 to 50%.
Thereby, high thermal conductivity can be imparted to the elastic layer while preventing the hardness of the elastic layer from becoming higher than necessary. Further, it is possible to reliably prevent temperature unevenness from occurring on the outer surface of the roller body.

In the fixing roller of the present invention, the fibrous carbonaceous material preferably has a thermal conductivity in the axial direction of 2 W / m · K or more.
By using a fibrous carbon-based material having a high thermal conductivity in this way, the thermal conductivity of the elastic layer is further improved, and as a result, the entire fixing roller can be warmed more quickly and reliably.

In the fixing roller of the present invention, the fibrous carbon-based material preferably has a tensile elastic modulus of 200 GPa or less.
Such a fibrous carbon-based material having a low tensile elastic modulus indicates high flexibility, and even when a relatively large amount is mixed in the elastic layer, it is possible to reliably prevent the elastic layer from increasing in hardness. be able to.

In the fixing roller of the present invention, it is preferable that the fibrous carbonaceous material is mainly composed of carbon fibers.
Since carbon fibers are relatively unlikely to be entangled with each other, this operation (work) is more required when electrostatic flocking is used when arranging a fibrous carbon-based material on the outer surface of the roller body. This is preferable because it can be performed reliably. Carbon fibers (particularly pitch-based carbon fibers) have high thermal conductivity and are highly isotropic with respect to thermal conduction. For this reason, the heat from the heater can be transmitted to the outer peripheral surface of the fixing roller more reliably and without waste.

In the fixing roller of the present invention, the elastic layer preferably has an average thickness of 1.1 to 2 times the maximum length of the carbon fiber.
Thereby, it can prevent suitably that carbon fiber protrudes unintentionally from an elastic layer. Moreover, it can also prevent suitably that the part in which carbon fiber does not exist in the outer surface side of an elastic layer increases, and the heat conductivity of an elastic layer falls.

In the fixing roller of the present invention, the elastic layer preferably has an Asker C hardness of 20 degrees or less.
Since such an elastic layer has sufficient flexibility, a sufficient area of the nip portion can be secured in the fixing device. Thereby, fixing failure of an unfixed image onto the recording medium can be prevented more reliably.

The fixing roller manufacturing method of the present invention includes a first step of disposing a fibrous carbonaceous material on the outer peripheral surface side of the roller body so as to be oriented in the radial direction of the roller body;
A second step of filling an elastic material or a liquid filler containing a precursor thereof between at least the fibrous carbonaceous materials;
And a third step of curing the liquid filler to obtain an elastic layer containing the fibrous carbonaceous material and the elastic material.
As a result, a fixing roller capable of improving the thermal conductivity in the thickness direction of the elastic layer and shortening the startup time of the fixing device can be obtained.

The fixing roller manufacturing method of the present invention preferably includes a step of forming an adhesive layer on the outer surface side of the roller body prior to the first step.
Thereby, a fibrous carbonaceous material can be reliably fixed with respect to a roller main body.
In the fixing roller manufacturing method of the present invention, in the first step, the fibrous carbon is applied by applying a voltage between a mounting table on which the fibrous carbon-based material is placed and the roller body. The system material is preferably arranged so as to be substantially perpendicular to the outer surface of the roller body.
According to such a method (so-called electrostatic flocking), it is easy to align the orientation direction of the fibrous carbonaceous material.

In the fixing roller manufacturing method of the present invention, the electric field strength between the mounting table and the roller body is preferably 5 × 10 ^{3 to} 5 × 10 ⁶ V / m.
Thereby, electrostatic flocking can be performed efficiently, controlling the orientation direction of a fibrous carbonaceous material reliably.
The fixing device of the present invention includes a fixing roller and a pressure roller pressed against the fixing roller, and allows a recording medium carrying an unfixed image to pass between the fixing roller and the pressure roller. A fixing device for fixing the unfixed image on the recording medium,
At least one of the fixing roller and the pressure roller is constituted by the fixing roller of the present invention.
Accordingly, it is possible to provide a fixing device with a short start-up time and high reliability.
The image forming apparatus of the present invention includes the fixing device of the present invention.
Accordingly, it is possible to provide an image forming apparatus with a short start-up time and high reliability.

Preferred embodiments of a fixing roller, a fixing roller manufacturing method, a fixing device, and an image forming apparatus according to the present invention will be described below with reference to the accompanying drawings.
[Image forming apparatus]
First, the configuration of the image forming apparatus of the present invention will be described.
FIG. 1 is an overall configuration diagram of an image forming apparatus of the present invention provided with a fixing device of the present invention.

In the apparatus main body 2 of the image forming apparatus 1, an image carrier 3 composed of a photosensitive drum is disposed. The image carrier 3 is rotationally driven in the direction of the arrow shown by a driving unit (not shown).
Around the image carrier 3, a charging device 4 for uniformly charging the image carrier 3 along its rotation direction, and an exposure device for forming an electrostatic latent image on the image carrier 3 5, a rotary developing device 6 for developing an electrostatic latent image, and an intermediate transfer device 7 for primary transfer of a monochromatic toner image formed on the image carrier 3.

In the rotary developing device 6, a yellow developing device 6Y, a magenta developing device 6M, a cyan developing device 6C, and a black developing device 6K are mounted on a support frame 8, and the support frame 8 is rotationally driven by a drive motor (not shown). It is configured.
The plurality of developing devices 6Y, 6C, 6M, and 6K are selectively rotated so that the developing roller 6a of one developing device is opposed to the image carrier 3 every rotation of the image carrier 3. Has been.

Each of the developing devices 6Y, 6C, 6M, and 6K has a toner storage portion that stores toner of each color.
The intermediate transfer device 7 is disposed so as to face the image carrier 3 on the back surface of the intermediate transfer belt 11, the driving roller 9 and the driven roller 10, the intermediate transfer belt 11 driven in the direction of the arrow by the two rollers. A primary transfer roller 12, a transfer belt cleaner 13 for removing residual toner on the intermediate transfer belt 11, and a drive roller 9 are arranged to face the four-color full-color image formed on the intermediate transfer belt 11 as a recording medium ( And a secondary transfer roller 14 for transferring onto paper or the like.
A paper feed cassette 15 is disposed at the bottom of the apparatus main body 2, and a recording medium in the paper feed cassette 15 is discharged through a pickup roller 16, a recording medium conveyance path 17, a secondary transfer roller 14, and a fixing device 19. It is configured to be conveyed to the tray 20.

Next, the operation of the image forming apparatus configured as described above will be described.
When an image forming signal is input from a computer (not shown), the image carrier 3, the developing roller 6 a of the developing device 6 and the intermediate transfer belt 11 are rotationally driven. First, the outer peripheral surface of the image carrier 3 is charged by the charging device 4. The exposure device 5 selectively exposes the outer peripheral surface of the uniformly charged image carrier 3 according to the image information of the first color (for example, yellow) so that the electrostatic latent image of yellow An image is formed.

  At the position of the latent image formed on the image carrier 3, the yellow developing device 6 </ b> Y rotates and the developing roller 6 a comes into contact therewith, whereby the yellow electrostatic latent image toner image is formed on the image carrier 3. Next, the toner image formed on the image carrier 3 is transferred onto the intermediate transfer belt 11 by the primary transfer roller 12. At this time, the secondary transfer roller 14 is separated from the intermediate transfer belt 11.

In accordance with the second color, the third color, and the fourth color of the image formation signal, the above processing is repeated to form a latent image, develop, and transfer by one rotation of the image carrier 3 and the intermediate transfer belt 11, thereby forming an image. Four color toner images corresponding to the contents of the signals are superimposed and transferred on the intermediate transfer belt 11.
Then, at the timing when this full-color image reaches the secondary transfer roller 14, the recording medium is supplied from the conveyance path 17 to the secondary transfer roller 14, and at this time, the secondary transfer roller 14 is pressed against the intermediate transfer belt 11. A secondary transfer voltage is applied, and the full color toner image (unfixed image) on the intermediate transfer belt 11 is transferred onto the recording medium.

Then, by passing the recording medium carrying the toner image between the fixing roller 21 and the pressure roller 22, that is, through the fixing device 19, the toner image is heated and pressed and fixed on the recording medium. The toner remaining on the intermediate transfer belt 11 is removed by the transfer belt cleaner 13.
In the case of double-sided printing, the recording medium exiting the fixing device 19 is switched back so that the trailing edge is the leading edge, and is supplied to the secondary transfer roller 14 via the double-sided printing conveyance path 23, and the intermediate medium. The full color toner image on the transfer belt 11 is transferred onto the recording medium, and is again heated and pressed by the fixing device 19 to be fixed.
The fixing device 19 includes a fixing roller (fixing roller of the present invention) 21 having a heat source and a pressure roller 22 pressed against the fixing roller 21. A line connecting the axis of the fixing roller 21 and the axis of the pressure roller 22. Are arranged to have an angle of θ from the horizontal line. Note that 0 ° ≦ θ ≦ 30 °.

[Fixing device]
Hereinafter, the fixing device of the present invention will be described in detail.
2 to 6 show details of the fixing device shown in FIG. 1, FIG. 2 is a perspective view showing a partially broken section of the fixing device of the present invention, and FIG. 3 shows the fixing device shown in FIG. 4 is a side view showing a mounting state of the pressure roller and the fixing roller shown in FIG. 2, FIG. 5 is a sectional view of the pressure roller shown in FIG. 2, and FIG. FIG. 3 is a cross-sectional view of the fixing roller shown in FIG. 2.

As shown in FIGS. 2 and 3, a fixing roller 21 is rotatably mounted in the housing 24 of the fixing device 19, and a driving gear 28 is connected to one end of the fixing roller 21.
A pressure roller 22 is rotatably mounted facing the fixing roller 21. The axial length of the pressure roller 22 is shorter than that of the fixing roller 21, and a bearing 25 is provided in the empty space, and both ends of the pressure roller 22 are supported by the bearing 25.

A pressure lever 26 is rotatably provided on the bearing 25, and a pressure spring 27 is disposed between one end of the pressure lever 26 and the housing 24, whereby the pressure roller 22 and the fixing roller 21 are added. It is configured to be pressed (pressure contact).
Support shafts 29 and 30 are provided on both side surfaces of the housing 24, and a separation member 31 on the fixing roller 21 side and a separation member 32 on the pressure roller 22 side rotate on the support shafts 29 and 30, respectively. Mounted freely. Accordingly, the peeling members 31 and 32 are disposed on the downstream side of the nip portion N (see FIG. 4) in the recording medium conveyance direction in the axial direction between the fixing roller 21 and the pressure roller 22.

As shown in FIG. 5, the pressure roller 22 includes a metal cylinder 221, a rotation shaft 222 fixed to the cylinder 221, a bearing 25 that supports the rotation shaft 222, and an outer periphery of the cylinder 221. It has the elastic layer 223 comprised with the provided silicone rubber etc., and the surface layer 224 coat | covered on the surface of the elastic layer 223.
The surface layer 224 is made of, for example, fluorine rubber, fluorine resin (for example, pertetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA)), or the like. By providing the surface layer 224 made of such a material, it is possible to prevent toner from adhering to the pressure roller 22 (surface layer 224).
In addition, the rotating shaft 222 is not limited to being configured by a hollow body as illustrated, and may be configured by a solid body.

As shown in FIG. 6, the fixing roller 21 includes a roller main body 210, an elastic layer 214 provided on the outer peripheral surface (surface) of the roller main body 210, and a surface layer 215 provided on the outer peripheral surface of the elastic layer 214. Have.
The roller body 210 includes a cylindrical body 210a and a cylindrical rotating shaft 210b fixed in the cylindrical body 210a.

A heater (heat source) 211 such as a halogen lamp is installed in the roller body 210 (rotary shaft 210b).
With such a configuration, the cylindrical body 210a, the elastic layer 214, and the surface layer 215 rotate integrally with the rotation shaft 210b as the center (axis), and the entire fixing roller 21 is warmed by the heater 211.

The roller body 210 (the cylindrical body 210a and the rotating shaft 210b) is made of a material having good thermal conductivity, such as a metal material.
The elastic layer 214 includes a fibrous carbonaceous material 212 oriented in the thickness direction, and an elastic material 213 that fixes the fibrous carbonaceous material 212.
Thereby, the heat from the heater 211 can be transmitted to the outer surface of the fixing roller 21 via the fibrous carbonaceous material 212. For this reason, even when the elastic material 213 having a relatively low thermal conductivity is used, the thermal conductivity in the thickness direction of the entire elastic layer 214 can be increased. As a result, the entire fixing roller 21 can be quickly and reliably warmed (quick heat), and the start-up time of the fixing device 19 (image forming apparatus 1) can be shortened.

For example, the image forming apparatus 1 can be activated in about 60% of the time when a fixing roller having an elastic layer that does not contain a fibrous carbonaceous material is used.
In addition, since the fibrous carbon-based material 212 is a relatively soft (highly flexible) material, it is possible to prevent the elastic layer 214 from increasing in hardness. Therefore, a sufficient area of the nip portion N formed when the pressure roller 22 is brought into pressure contact can be ensured, and as a result, it is possible to reliably prevent a fixing failure of an unfixed image on the recording medium. be able to.

Here, it is preferable that the fibrous carbon-based material 212 is substantially perpendicular to the outer peripheral surface of the roller body 210 (tubular body 210a) in a state where the fibrous carbon-based material 212 is oriented in the thickness direction of the elastic layer 214. The roller body 210 may be slightly inclined with respect to the outer peripheral surface.
Further, in the state in which the fibrous carbonaceous material 212 is oriented, it is sufficient that the majority of the fibrous carbonaceous materials 212 are aligned in the same direction. The system material 212 may be included.

Examples of the fibrous carbon-based material 212 include carbon fibers (for example, pitch-based, PAN-based, etc.), carbon nanotubes such as single-walled carbon nanotubes and multi-walled carbon nanotubes, and one or two of them A combination of the above can be used.
Among these, the fibrous carbon-based material 212 preferably has a thermal conductivity in the axial direction of 2 W / m · K or more, and more preferably 5 W / m · K or more. By using the fibrous carbonaceous material 212 having a high thermal conductivity in this way, the thermal conductivity of the elastic layer 214 is further improved, and as a result, the entire fixing roller 21 can be warmed more quickly and reliably. .

  Further, the fibrous carbon-based material 212 is slightly different depending on the amount to be contained in the elastic layer 214, but the tensile elastic modulus is preferably 200 GPa or less, more preferably 150 GPa or less. Thus, the fibrous carbon-based material 212 having a low tensile elastic modulus shows high flexibility, and even when a relatively large amount is mixed with the elastic layer 214, the hardness of the elastic layer 214 is surely increased. Can be prevented.

In other words, since a relatively large amount of fibrous carbon-based material 212 can be mixed in the elastic layer 214, the thermal conductivity of the elastic layer 214 can be further improved, and as a result, the entire fixing roller 21 can be further improved. It becomes possible to warm quickly and reliably.
As such a fibrous carbonaceous material 212, the thing which has carbon fiber (especially pitch-type carbon fiber) as a main component is preferable.

Since carbon fibers are relatively unlikely to be entangled with each other, when electrostatic flocking as described later is used when arranging the fibrous carbon-based material 212 on the outer surface of the roller body 210, It is preferable because the operation (work) can be performed more reliably.
Carbon fibers (particularly pitch-based carbon fibers) have high thermal conductivity and are highly isotropic with respect to thermal conduction. For this reason, the heat from the heater 211 can be transmitted to the outer peripheral surface of the fixing roller 21 more reliably and without waste.

Further, the content of the fibrous carbonaceous material 212 in the elastic layer 214 is preferably about 20 to 50%, and more preferably about 40 to 50%. Accordingly, it is possible to impart high thermal conductivity to the elastic layer 214 while preventing the hardness of the elastic layer 214 from becoming higher than necessary. In addition, it is possible to reliably prevent temperature unevenness from occurring on the outer surface of the roller body 210.
Note that the content and arrangement density of the fibrous carbon-based material 212 in the elastic layer 214 can be determined by, for example, the adhesive described later when the fibrous carbon-based material 212 is disposed on the outer surface side of the roller body 210. It can be set appropriately by adjusting the coating density and the like.

  On the other hand, examples of the elastic material 213 include silicone rubber, fluorine rubber, natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, nitrile rubber, chloroprene rubber, butyl rubber, acrylic rubber, ethylene-propylene rubber, hydrin rubber, and urethane rubber. Rubber materials (especially vulcanized) such as styrene, polyolefin, polyvinyl chloride, polyurethane, polyester, polyamide, polybutadiene, trans polyisoprene, fluoro rubber, chlorinated Examples include various thermoplastic elastomers such as polyethylene, and one or more of these can be used in combination.

Among these, as the elastic material 213, a material mainly composed of silicone rubber is preferable. Silicone rubber is particularly preferable because it is excellent in heat resistance and excellent in elasticity (flexibility). Further, it is preferable because the elastic layer 214 can be easily formed by using a method (LIM molding) as will be described later.
The average thickness of the elastic layer 214 is slightly different depending on the type of the fibrous carbonaceous material 212 and is not particularly limited, but is about 1.1 to 2 times the maximum length of the fibrous carbonaceous material 212. It is preferable that the ratio is about 1.1 to 1.5 times. Thereby, it can prevent suitably that the fibrous carbonaceous material 212 protrudes from the elastic layer 214 unintentionally. Further, it is possible to suitably prevent the portion where the fibrous carbon-based material 212 is not present on the outer surface side of the elastic layer 214 from increasing and the thermal conductivity of the elastic layer 214 from being lowered.

The thickness of the elastic layer 214 is preferably smaller than the thickness of the elastic layer 223 of the pressure roller 22. As a result, as shown in FIG. 4, a nip portion N having a concave shape on the pressure roller 22 side can be reliably formed.
In addition, when using a carbon fiber as the fibrous carbonaceous material 212, the average thickness of the elastic layer 214 is preferably about 1 to 5 mm, and more preferably about 0.75 to 2 mm.

  Further, the hardness of such an elastic layer 214 is preferably 20 degrees or less in Asker C (specified in SRIS 0101). Since the elastic layer 214 has sufficient flexibility, a sufficient contact area with the pressure roller 22 (area of the nip portion N) can be secured. Thereby, fixing failure of an unfixed image onto the recording medium can be prevented more reliably.

A surface layer (peeling layer) 215 is provided on the outer peripheral surface of the elastic layer 214.
The surface layer 215 is mainly composed of a resin material. The resin material is not particularly limited, and examples thereof include fluorine-based resins such as pertetrafluoroethylene (PTFE) and tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA). Among these, One kind or a combination of two or more kinds can be used. Thereby, it is possible to prevent the toner from adhering to the fixing roller 21 (surface layer 215).

In addition, the average thickness of the surface layer 215 is not specifically limited, It is preferable that it is about 1-100 micrometers, and it is more preferable that it is about 30-50 micrometers.
In the fixing device 19 as described above, since the fibrous carbonaceous material 212 is arranged in the fixing roller 21 so that the axes are aligned along the thickness direction of the elastic layer 214, the thickness of the elastic layer 214. The heat conductivity in the direction is improved, and the heat from the heater 211 can be reliably transmitted to the recording medium without lowering the thermal efficiency.

Further, since the thermal conductivity in the thickness direction of the elastic layer 214 is improved, the outer surface of the fixing roller 21 can be quickly and reliably heated (that is, quick heat). Thereby, the fixing device 19 can surely shorten the activation time.
The configuration of the fixing roller 21 described above can also be applied to the pressure roller 22. That is, the fixing roller of the present invention can be applied to one or both of a pair of rollers provided in the fixing device 19.

Further, for example, in the fixing roller 21, the case where the heater 211 such as a halogen lamp is provided inside the roller body 210 has been described as an example, but the heater is provided between the roller body 210 and the elastic layer 214. It can also be composed of a heat generating layer.
Further, the heat generating layer may be arranged in the roller main body 210 along the inner peripheral surface thereof and at a position separated from the rotation center via the inner peripheral surface and a gap.
When the heater is provided as a heat generation layer between the roller body 210 and the elastic layer 214, the rotation shaft 210b of the fixing roller 21 may be formed of a solid body.

Next, a method for manufacturing the fixing roller 21 described above (a method for manufacturing the fixing roller of the present invention) will be described with reference to FIGS.
[1] First, the roller body 210 as described above is prepared.
[2] Next, as shown in FIG. 7A, an adhesive layer 219 is formed on the outer peripheral surface of the roller body 210.
Examples of the adhesive used for the adhesive layer 219 include various adhesives such as silicone, acrylic, epoxy, and urethane. Further, for example, conductive fillers such as metal (silver, gold, platinum, copper, nickel) particles, metal oxide particles, amorphous carbon particles, graphite particles, and silver-plated particles are added to these adhesives. It may be.

[3] Next, as shown in FIG. 7 (b), a fibrous carbon-based material is oriented on the outer peripheral surface of the adhesive layer 219 (the outer peripheral surface side of the roller main body 210) in the radial direction of the roller main body 210. The substance 212 is disposed (first step).
This is suitably achieved by using a method as shown in FIG. 8 (so-called electrostatic flocking). According to such electrostatic flocking, it is easy to align the orientation direction of the fibrous carbonaceous material 212.

FIG. 8 is a schematic diagram for explaining electrostatic flocking. In the following description, it is assumed that the upper side in FIG. 8 is “upper” and the lower side is “lower”.
Specifically, the fibrous carbon-based material 212 is mounted on the mounting table 40, and the upper surface of the mounting table 40 and the roller main body 210 are disposed substantially in parallel.
Next, a voltage is applied so that the mounting table 40 is positive and the roller body 210 is negative. As a result, negative charges are accumulated on the outer surface of the roller body 210 and positive charges are accumulated on the uppermost portion of the fibrous carbonaceous material 212 placed on the placing table 40.

  When a voltage is applied so that the electrostatic force generated by the electric field between the roller main body 210 and the mounting table 40 exceeds the gravity applied to the fibrous carbonaceous material 212, the placement of the fibrous carbonaceous material 212 is increased. As shown in FIG. 8, in order from the one positioned at the top of the mounting table 40, the roller body 210 is attracted to the roller body 210 with its axial direction maintained substantially perpendicular to the outer surface of the roller body 210. Flying towards.

Then, the fibrous carbonaceous material 212 that has reached the outer surface of the roller body 210 collides with the adhesive layer 219 and is securely fixed.
At this time, the roller body 210 can be disposed over the entire outer peripheral surface of the adhesive layer 219 by rotating the roller body 210 around the rotation shaft 210b.
The electric field strength between the mounting table 40 and the roller main body 210 at this time is not particularly limited, but is preferably 5 × 10 ^{3 to} 5 × 10 ⁶ V / m, and 1 × 10 ⁴ to 1 × 10 ^6. More preferably, it is V / m. If the electric field strength is too small, there is a possibility that electrostatic flocking cannot be performed efficiently. On the other hand, if the upper limit is exceeded, the electrostatic force is too large, and the orientation control of the fibrous carbonaceous material 212 becomes difficult. Show the trend.
Next, a curing process is performed on the adhesive layer 219 as necessary. Thereby, the roller body 210 and the fibrous carbonaceous material 212 are more firmly fixed via the adhesive layer 219.
The mounting table 40 and the roller body 210 may be upside down.

[4] Next, at least between the fibrous carbonaceous materials 212 (in this embodiment, so as to cover the upper ends of the fibrous carbonaceous materials 212), a liquid filler containing an elastic material or a precursor thereof is filled. (Second step).
Examples of the solvent used for preparing the liquid filling include ketone solvents such as methyl ethyl ketone (MEK), acetone, diethyl ketone, methyl isobutyl ketone (MIBK), methyl isopropyl ketone (MIPK), cyclohexanone, methanol, ethanol, Alcohol solvents such as isopropanol, ethylene glycol, diethylene glycol (DEG), glycerin, diethyl ether, diisopropyl ether, 1,2-dimethoxyethane (DME), 1,4-dioxane, tetrahydrofuran (THF), tetrahydropyran (THP), Ether solvents such as anisole, diethylene glycol dimethyl ether (diglyme), diethylene glycol ethyl ether (carbitol), methyl acetate, ethyl acetate, butyl acetate Ester solvents such as ethyl formate, cellosolve solvents such as methyl cellosolve, ethyl cellosolve, phenyl cellosolve, aliphatic hydrocarbon solvents such as hexane, pentane, heptane, cyclohexane, toluene, xylene, benzene, trimethylbenzene, tetramethylbenzene Aromatic hydrocarbon solvents such as pyridine, pyrazine, furan, pyrrole, thiophene, methylpyrrolidone and other aromatic heterocyclic compounds solvents, N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMA) Amide solvents such as dichloromethane, chloroform, 1,2-dichloroethane and the like, sulfur compound solvents such as dimethyl sulfoxide (DMSO) and sulfolane, acetonitrile, propionitrile, acrylonitrile and the like. Lil solvent or a mixed solvent thereof and the like can be mentioned.

The filling of the liquid filling is, for example, a method in which the roller main body 210 in which the fibrous carbonaceous material 212 is disposed is set in a mold having an inner surface corresponding to the outer surface shape of the fixing roller 21 and injected. It can be suitably performed by using so-called LIM molding (Liquid Injection Molding).
In addition, you may make it perform filling with a liquid filling using various coating methods, such as an inkjet method and brush coating.

[5] Next, the liquid filling is cured to obtain the elastic layer 214 as shown in FIG.
When the elastic material itself is contained in the liquid filling material, the liquid filling material can be cured (solidified) by a dedispersion medium by heating, vacuum drying, or the like.
On the other hand, when a precursor of an elastic material is included in the liquid filler, the liquid filler is cured (solidified) by changing the precursor to an elastic material by, for example, heating, ultraviolet irradiation, or the like. Can.
In addition, when using the precursor of a silicone rubber as a precursor of an elastic material, a heating at about 100-150 degreeC is performed.

[6] Next, as shown in FIG. 7D, a surface layer 215 is formed on the outer peripheral surface of the elastic layer 214.
The surface layer 215 can be formed by, for example, a method of heating after coating an extrusion molding, a LIM molding, or a heat shrinkable tube.
[7] Next, the heater 211 is installed inside the roller body 210 (rotating shaft 210b).
The fixing roller 21 is manufactured through the above steps.

In such a fixing roller 21, the fibrous carbonaceous material 212 is fixed to the outer peripheral surface of the roller body 210 via the adhesive layer 219, and the elastic material 213 is filled so as to fill the space between the fibrous carbonaceous materials 212. Filled. For this reason, the anchoring effect with respect to the elastic material 213 of the fibrous carbonaceous material 212 is exhibited, and there also exists an advantage that peeling from the roller main body 210 of the elastic material 213 (elastic layer 214) can be prevented.
As described above, the fixing roller, the method for manufacturing the fixing roller, the fixing device, and the image forming apparatus of the present invention have been described with respect to the illustrated embodiments. However, the present invention is not limited to this.
For example, each part constituting the fixing roller, the fixing device, and the image forming apparatus can be replaced with an arbitrary configuration that can exhibit the same function. Moreover, arbitrary components may be added.

1 is an overall configuration diagram of an image forming apparatus of the present invention including a fixing device of the present invention. FIG. 3 is a perspective view showing a partially broken section of the fixing device of the present invention. FIG. 3 is a plan view of the fixing device shown in FIG. 2. It is a side view which shows the attachment state of the pressure roller and fixing roller shown in FIG. FIG. 3 is a cross-sectional view of the pressure roller shown in FIG. 2. FIG. 3 is a cross-sectional view of the fixing roller shown in FIG. 2. It is a figure explaining the manufacturing method of the fixing roller shown in FIG. It is a schematic diagram for demonstrating electrostatic flocking.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 2 ... Main body 3 ... Image carrier 4 ... Charging device 5 ... Exposure device 6 ... Rotary developing device 6Y ... Yellow developing device 6M ... Magenta developing device 6C ... Cyan developing device 6K: Black developing device 6a: Developing roller 7 ... Intermediate transfer device 8 ... Support frame 9 ... Driving roller 10 ... Driven roller 11 ... Intermediate transfer belt 12 ... Primary transfer roller 13 Transfer belt cleaner 14 Secondary transfer roller 15 Feed cassette 16 Pickup roller 17 Recording medium transport path 19 Fixing device 20 Discharge tray 21 Fixing roller 210 Roller Main body 210a …… Cylinder 210b …… Rotating shaft 211 …… Heater 212 …… Fibrous carbon-based material 213 …… Elastic material 214 …… Elastic layer 215 …… Surface layer 19 …… Adhesive layer 22 …… Pressure roller 221 …… Cylinder 222 …… Rotating shaft 223 …… Elastic layer 224 …… Surface layer 23 …… Double-sided printing conveyance path 24 …… Housing 25 …… Bearing 26 …… Pressure lever 27 …… Pressure spring 28 …… Drive gear 29, 30 …… Support shaft 31, 32 …… Peeling member 40 …… Place N …… Nip part

Claims (14)

A fixing roller having a roller body and an elastic layer provided on an outer peripheral side of the roller body,
The fixing roller, wherein the elastic layer includes a fibrous carbon-based material oriented in a thickness direction thereof, and an elastic material that fixes the fibrous carbon-based material.   The fixing roller according to claim 1, wherein the elastic material is mainly composed of silicone rubber.   The fixing roller according to claim 1, wherein a content ratio of the fibrous carbon-based material in the elastic layer is 20 to 50%.   4. The fixing roller according to claim 1, wherein the fibrous carbonaceous material has a thermal conductivity in the axial direction of 2 W / m · K or more. 5.   The fixing roller according to claim 1, wherein the fibrous carbon-based material has a tensile elastic modulus of 200 GPa or less.   The fixing roller according to claim 5, wherein the fibrous carbonaceous material is mainly composed of carbon fiber.   The fixing roller according to claim 1, wherein an average thickness of the elastic layer is 1.1 to 2 times a maximum length of the carbon fiber.   8. The fixing roller according to claim 1, wherein the elastic layer has an Asker C hardness of 20 degrees or less. A first step of disposing a fibrous carbonaceous material on the outer peripheral surface side of the roller body so as to be oriented in the radial direction of the roller body;
A second step of filling an elastic material or a liquid filler containing a precursor thereof between at least the fibrous carbonaceous materials;
A method of manufacturing a fixing roller, comprising: a third step of curing the liquid filling to obtain an elastic layer containing the fibrous carbonaceous material and the elastic material.   The method for manufacturing a fixing roller according to claim 9, further comprising a step of forming an adhesive layer on an outer surface side of the roller body prior to the first step.   In the first step, by applying a voltage between the mounting body on which the fibrous carbon-based material is mounted and the roller body, the fibrous carbon-based material is applied to the outer surface of the roller body. The method for manufacturing a fixing roller according to claim 9, wherein the fixing roller is arranged so as to be substantially vertical. The method for manufacturing a fixing roller according to claim 11, wherein the electric field strength between the mounting table and the roller body is 5 × 10 ^{3 to} 5 × 10 ⁶ V / m. A fixing roller; and a pressure roller pressed against the fixing roller, and passing a recording medium carrying an unfixed image between the fixing roller and the pressure roller, thereby allowing the recording medium to pass through the recording medium. A fixing device for fixing an unfixed image,
9. A fixing device, wherein at least one of the fixing roller and the pressure roller is constituted by the fixing roller according to claim 1. An image forming apparatus comprising the fixing device according to claim 13.

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