JP5504192B2 - Fixing device, fixing member manufacturing method, and image forming apparatus - Google Patents

Description

  The present invention relates to a fixing member obtained by coating a fluororesin film on the outer surface of a silicone rubber layer formed on the surface of a core material, a manufacturing method thereof, a fixing device including the fixing member, and an image forming apparatus including the fixing device. Is.

  In an image forming apparatus such as a copying machine or a printer that forms an image on a recording material such as paper by an electrophotographic method, a toner is developed by developing an electrostatic latent image formed on an image carrier such as a photosensitive drum by a developing device. An image is visualized and the toner image is transferred onto a recording material. Then, the recording material onto which the toner image has been transferred is conveyed to a fixing device, heated and pressurized by the fixing device, and after being fixed on the toner image, it is discharged out of the apparatus, thereby performing a series of image forming operations. Is completed.

  Incidentally, as a fixing method of the fixing device in such an image forming apparatus, a heating roller method and a fixing belt method are conventionally known. Here, a fixing device that employs a heating roller system will be described as an example.

  That is, a fixing device that employs a heating roller method as a fixing method includes a fixing roller and a pressure roller that rotate in contact with each other, and a fixing heater is disposed inside the cylindrical fixing roller. The pressure roller is formed by forming a silicone rubber layer on the outer surface of the cored bar and coating the outer surface with a fluororesin film (PFA tube or the like) as a release layer.

  Incidentally, in recent years, volatile organic compounds (VOC) generated from electronic devices have been regulated by various environmental standards, and volatile organic compounds (VOC) generated from image forming apparatuses are generated from fixing devices. Siloxane accounts for a large percentage. Most of the siloxane generation sources are those generated from silicone rubber contained in the fixing roller and pressure roller. In order to comply with environmental standards, how to reduce the amount of siloxane generated from this silicone rubber? Has become an issue. Also, if the surface of electrical circuits or relay contacts is contaminated by this siloxane, problems such as contact failure will occur, and if siloxane adheres to the mirror of the optical system, the optical performance will deteriorate. Therefore, reducing the amount of siloxane is a major challenge.

  Therefore, in Patent Document 1, a cap member that is opposed to both ends of the silicone rubber layer included in the sheet conveying roller via a gap is provided on the core metal, and at least an outer periphery of the cap member is covered with a resin tube, and the gap is formed. The structure which seals is proposed.

  Further, Patent Document 2 proposes a configuration in which an adsorbent that adsorbs a volatile organic compound is provided on a core metal located at both ends of a silicone rubber layer included in a sheet conveying roller.

JP 2008-009264 A JP 2008-009265 A

  However, according to the configuration proposed in Patent Document 1, since the cap member is newly required and the number of parts is increased, and the cap member is disposed through the gap, the groove is formed in the resin tube in the gap portion. If the cap member is located in the nip with the opposing roller, the cap member may be damaged by repeated rotation and stop of the sheet conveying roller. There is. In order to avoid this, if the cap member is disposed outside the nip with the counter roller, there arises a problem that the fixing device becomes large. Furthermore, the cap member needs to have a thickness of 5 mm or more because it is necessary to suppress vibration due to rotation by itself, and this also causes a problem that the fixing device becomes large.

  Moreover, even if it is the structure proposed in patent document 2, since the condition where the adsorption body is covered with the resin tube is the same as patent document 1, the same problem as the above will generate | occur | produce.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and the object of the present invention is a fixing member that can prevent the volatile organic compound siloxane from being diffused, a manufacturing method thereof, and a fixing device that can be miniaturized. And providing an image forming apparatus including the same.

  In order to achieve the above object, a first aspect of the present invention provides a fixing member in which a silicone rubber layer is formed on a core material and a fluororesin film is coated on the outer surface of the silicone rubber layer. Activated carbon is mixed in an end surface portion that is not covered with the fluororesin film and exposed to the outside.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, the content of the activated carbon is set to 10 to 30% by weight.

  The invention according to claim 3 is a method of manufacturing a fixing member in which a silicone rubber layer is formed on a core material, and an outer surface of the silicone rubber layer is coated with a fluororesin film, the core material and the fluororesin A liquid silicone rubber mixed with activated carbon is poured into the space between the core material of the vertical mold in which a film is inserted and set and the fluororesin film by a predetermined height. The liquid silicone rubber, which is not contained or contained at a lower content than the end portion, is poured by a predetermined height, and then the liquid silicone rubber mixed with activated carbon is poured by a predetermined height, and then the state is reached. It is characterized by being vulcanized while maintaining.

  According to a fourth aspect of the present invention, there is provided a fixing device including the fixing member according to the first or second aspect or the fixing member manufactured by the manufacturing method according to the third aspect.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, an end face portion mixed with activated carbon of the silicone rubber layer included in the fixing member is disposed outside the image area.

  The invention according to claim 6 is the invention according to claim 4 or 5, wherein the outer diameter or thickness of the end surface portion where the activated carbon of the silicone rubber layer contained in the fixing member is mixed is set to the outer diameter or thickness of the central portion. It is characterized by being set smaller than this.

  An image forming apparatus according to a seventh aspect includes the fixing device according to any one of the fourth to sixth aspects.

  According to the first aspect of the present invention, the activated carbon is mixed into the end face portion which is not covered with the fluororesin film of the silicone rubber layer and exposed to the outside, that is, the end face portion where siloxane which is a volatile organic compound has been diffused conventionally. Therefore, the siloxane generated in the silicone rubber is adsorbed by the activated carbon, and the siloxane is prevented from being diffused out of the fixing member.

  According to the invention described in claim 2, by setting the content of the activated carbon to 10 to 30% by weight, the performance and strength of the elastic body of silicone rubber are suppressed while suppressing the release of siloxane to the outside of the fixing member. The durability of the fixing member can be improved by preventing the decrease. Incidentally, if the content of activated carbon is less than 10% by weight, the effect of suppressing the release of siloxane to the outside of the fixing member cannot be expected, and conversely, if the content of activated carbon exceeds 30% by weight, the elasticity of silicone rubber The performance and strength of the body are lowered, and the durability of the fixing member is also lowered.

  According to the invention of claim 3, a liquid silicone rubber in which activated carbon is mixed in the space between the core material of the vertical mold in which the core material and the fluororesin film are inserted and set in advance, and the fluororesin film, A liquid silicone rubber containing no activated carbon or containing less activated carbon, and a liquid silicone rubber mixed with activated carbon are poured in order, and then vulcanized while maintaining the state of siloxane. Therefore, it is possible to manufacture a fixing member that can prevent the diffusion of the toner to the outside with high productivity.

  According to the fourth aspect of the present invention, the fixing member provided in the fixing device is structurally only mixed with the activated carbon in the end surface portion exposed to the outside of the silicone rubber layer, and changes in shape and size. Therefore, the total length does not become longer like a fixing member newly provided with a cap member or adsorbing member on the end face of the silicone rubber layer to prevent siloxane from being released to the outside, and the fixing device can be downsized. It is done.

  According to the invention of claim 5, since the end surface portion of the silicone rubber layer of the fixing member whose apparent hardness is higher than other portions (image region portion) because it includes activated carbon is disposed outside the image region, In the image area, an appropriate fixing nip is formed by the fixing member, and the toner image is well fixed on the recording material.

  According to the sixth aspect of the present invention, the outer diameter or thickness of the end face portion mixed with the activated carbon of the silicone rubber layer whose apparent hardness is higher than that of the other portion due to the inclusion of the activated carbon is set to the outside of the central portion. Since the diameter is set smaller than the thickness or thickness, the pressure per unit area in the fixing nip formed by the fixing member is made uniform in the longitudinal direction, and the toner image is well fixed on the recording material.

  According to the seventh aspect of the invention, since siloxane is prevented from being diffused from the fixing device, it is possible to ensure high fixability and stably obtain a high quality image while preventing deterioration of the environment.

1 is a cross-sectional view of an image forming apparatus according to the present invention. FIG. 3 is a cross-sectional view of a main part of the fixing device according to the present invention. It is a cross-sectional view of the pressure roller according to the present invention. It is the A section enlarged detail drawing of FIG. (a)-(d) is sectional drawing which shows the manufacturing method of the pressure roller which concerns on this invention in the order of the process. FIG. 3 is a side view of a fixing belt according to the present invention. It is the BB sectional view taken on the line of FIG. It is the C section enlarged detail drawing of FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

[Image forming apparatus]
FIG. 1 is a cross-sectional view of an image forming apparatus according to the present invention. The illustrated image forming apparatus 1 is a laser printer, and an image forming unit 2 is disposed above the inside of the apparatus main body 1A. A sheet storage unit 3 is disposed in the lower half of the sheet.

  The image forming unit 2 forms an image by an electrophotographic method. The image forming unit 2 is a photosensitive drum 4 as a rotatable image carrier, a charger 5 disposed around the photosensitive drum 4, a developing device 6, and the like. In addition to the transfer roller 7 and the cleaning device 8, the developing device 6 is provided with a toner hopper 9 for supplying toner as a developer. A laser scanner unit (LSU) 10 that is an optical scanning device is disposed beside the image forming unit 2.

The paper storage unit 3 includes detachable upper and lower two-stage paper feed cassettes 11 and 12 in which a plurality of paper sheets as recording materials are stacked and accommodated, and in the vicinity of each of the paper feed cassettes 11 and 12, A pick roller 13 for sequentially taking out the paper in each of the paper feed cassettes 11 and 12 from the upper one, a feed roller 14 for feeding out the taken paper one by one and a retard roller 15 are provided. In the apparatus main body 1A, a first transport path S1 from the paper storage unit 3 to the image forming unit 2 and a second transport path S2 from the image forming unit 2 to the paper discharge tray 16 are disposed. The registration roller 17 and the transfer roller 7 are provided in the path S1, and the fixing device 18, the conveyance roller 19, and the paper discharge roller 20 according to the present invention are provided in the second conveyance path S2. Details of the configuration of the fixing device 18 will be described later.

  Next, an image forming operation of the image forming apparatus 1 configured as described above will be described.

  When the image forming operation is started, in the image forming unit 2, the photosensitive drum 4 is rotationally driven in a direction indicated by an arrow (clockwise) in FIG. Uniformly charged. When a laser beam based on an electrical signal transmitted from a personal computer or the like is output from the laser scanner unit 10 and the surface of the photosensitive drum 4 is exposed and scanned, an electrostatic latent image corresponding to image information is formed on the photosensitive drum 4. Is formed. The electrostatic latent image formed on the photosensitive drum 4 is developed by the developing device 6 using toner as a developer to be visualized as a toner image.

  By the way, when cassette feeding is performed, the paper stored in, for example, the upper paper feeding cassette 11 of the paper storage unit 3 is picked up from the uppermost one by the pick roller 13 and is fed by the feed roller 14 and the retard roller 15. The sheets are separated one by one and conveyed to the registration roller 17 through the first conveyance path S1. In the registration roller 17, after the paper is temporarily in a standby state, the paper is supplied to the image forming unit 2 at a predetermined timing synchronized with the toner image on the photosensitive drum 4.

  In the image forming unit 2, the sheet supplied to the transfer nip between the photosensitive drum 4 and the transfer roller 7 is conveyed while being pressed against the photosensitive drum 4 by the transfer roller 7, so that the surface of the sheet is exposed to the photosensitive drum. The toner image on 4 is transferred. The sheet onto which the toner image has been transferred is conveyed to the fixing device 18 and is heated and pressurized in the process of passing through the fixing nip of the fixing device 18 to receive the toner image being fixed. The toner remaining on the surface of the photosensitive drum 4 (transfer residual toner) after the transfer of the toner image onto the paper is removed by the cleaning device 8, and the photosensitive drum 4 whose surface has been cleaned is prepared for the next image forming operation.

  Thus, the sheet on which the toner image is fixed on the surface by the fixing device 18 is conveyed toward the sheet discharge roller 20 by the conveyance roller 19 through the second conveyance path S2, and to the sheet discharge tray 16 by the sheet discharge roller 20. This completes a series of image forming operations.

[Fixing device]
Next, the fixing device 18 according to the present invention will be described below with reference to FIGS.

  2 is a cross-sectional view of the main part of the fixing device according to the present invention, FIG. 3 is a transverse cross-sectional view of the pressure roller of the identification fixing device, and FIG.

  The illustrated fixing device 18 employs a heating roller method as a fixing method, and includes a fixing roller 21 and a pressure roller 22 that are in contact with each other and rotate in a direction indicated by an arrow in the figure, and are cylindrical fixing rollers. A fixing heater 23 is disposed inside 21. A pressure roller 22 is pressed against the fixing roller 21 from below to form a predetermined fixing nip with the fixing roller 21.

  In the present embodiment, the fixing roller 21 is configured by coating the outer surface of an aluminum cored bar 24 with a fluororesin 25 such as PFA or PTFE filled with a conductive material or wear-resistant material. The fixing heater 23 disposed inside the fixing roller 21 is composed of a halogen lamp, and the fixing roller 21 is heated to a predetermined fixing temperature by the fixing heater 23. The surface temperature of the fixing roller 21 is always detected by a temperature sensor (not shown), and the detection signal is fed back to a controller (not shown) to control the surface temperature of the fixing roller 21 to a predetermined fixing temperature.

  The pressure roller 22 has a cylindrical silicone rubber layer 27 formed on the outer surface of a metal core 26 made of stainless steel or the like, and a PFA, PTFE, or the like as a release layer on the outer surface of the silicone rubber layer 27. The fluororesin film 28 is covered.

  Thus, in the present embodiment, as shown in FIG. 3, the longitudinal direction (paper passing width direction) exposed to the outside without being covered with the fluororesin film 28 of the silicone rubber layer 27 provided on the pressure roller 22. Activated carbon 29 shown in FIG. 4 is mixed in end face portions (width b portions) 27A at both ends. That is, in the pressure roller 22, the left and right end surface portions 27A of the silicone rubber layer 27 are made of activated carbon-rich silicone rubber. Here, the content of the activated carbon 29 is set to 10 to 30% by weight for reasons described later.

  In the fixing device 18 according to the present embodiment, the end surface portion 27A mixed with the activated carbon 29 of the silicone rubber layer 27 included in the pressure roller 22 is disposed outside the image area (non-image area). The outer diameter φD1 of these end face portions 27A is set to be smaller than the outer diameter φD2 of the central portion (φD1 <φD2).

  Here, the manufacturing method of the pressure roller 22 comprised as mentioned above is demonstrated below according to Fig.5 (a)-(d). 5A to 5D are cross-sectional views showing the method of manufacturing the pressure roller according to the present invention in the order of the steps.

  A vertical mold 30 is used for the production of the pressure roller 22, and the mold 30 is formed by vertically standing a cylindrical mold 31 having an inner diameter that is the same as the outer diameter of the pressure roller 22. The upper mold 32 and the lower mold 33 are respectively fitted on the upper and lower sides of the cylindrical mold 31.

  Thus, when the pressure roller 22 is manufactured, first, as shown in FIG. 5A, the core metal 26 is inserted into the center of the mold 30 and set vertically, and the cylindrical fluorine is used. A resin film (PFA tube) 28 is inserted and set along the inner surface of the cylindrical mold 31. Next, as shown in FIG. 5 (b), the activated carbon-rich liquid silicone rubber 27 a mixed with the activated carbon 29 is fed from the inlet 32 a formed at the center of the upper mold 32 to the core metal 26 in the mold 30. Then, a liquid silicone rubber 27b containing no activated carbon or containing less activated carbon is contained in the space between the resin film 28 and the fluororesin film 28 as shown in FIG. 5C. Pour only for height h. Finally, as shown in FIG. 5 (d), activated carbon-rich liquid silicone rubber 27a containing activated carbon is poured onto liquid silicone rubber 27b that does not contain activated carbon, and the state is vulcanized to obtain silicone rubber 27a. , 27b and the silicone rubber 27a, 27b, the core metal 26 and the fluororesin film 28 are integrated, and the pressure roller 22 in which activated carbon 29 is mixed with the left and right end portions of the silicone rubber layer 27 as shown in FIG. Is done.

  According to the manufacturing method of the pressure roller 22 described above, activated carbon 29 is placed in the space between the core metal 26 and the fluororesin film 28 of the vertical mold 30 in which the core metal 26 and the fluororesin film 28 are inserted and set in advance. Activated carbon-rich silicone rubber 27a, activated carbon 29-free silicone rubber 27b, activated carbon 29 mixed with activated carbon-rich silicone rubber 27a, and then vulcanized while maintaining that state, thereby allowing silicone The pressure roller 22 in which the activated carbon 29 is mixed with the left and right end surface portions 27A of the rubber layer 27 can be manufactured with high productivity.

  Thus, in the pressure roller 22 used in the fixing device 18 according to the present embodiment, the end surface portion 27A exposed to the outside without being covered with the fluororesin film 28 of the silicone rubber layer 27, that is, in the past, is volatilized. Since the activated carbon 29 is mixed with the end face portion 27A from which the siloxane, which is a volatile organic compound, has been diffused, the siloxane generated in the silicone rubber is adsorbed by the activated carbon 29, and the siloxane is prevented from being diffused out of the pressure roller 22. For this reason, it is possible to meet various environmental standards, contact failure due to contamination of the surface of electrical circuits, relay contacts, etc. by siloxane, deterioration of optical performance due to adhesion of siloxane to optical mirrors, etc. Is prevented from occurring.

  In addition, the pressure roller 22 used in the fixing device 18 according to the present embodiment is structurally only mixed with the activated carbon 29 in the end surface portion 27A exposed to the outside of the silicone rubber layer 27, and its shape. Therefore, the total length does not become longer like a pressure roller newly provided with a cap member or adsorbing member on the end face of the silicone rubber layer to prevent siloxane from being released to the outside. The size of the fixing device 18 can be reduced.

  Further, in the fixing device 18 according to the present embodiment, since the activated carbon 29 is included, the end surface portion of the silicone rubber layer 27 of the pressure roller 22 whose apparent hardness is higher than other portions (image region portions). Since 27A is arranged outside the image area (non-image area), an appropriate fixing nip is formed by the fixing roller 21 and the pressure roller 22 in the image area, the toner image is well fixed on the paper, and the environment is deteriorated. While preventing, high fixability can be secured and a high quality image can be obtained stably.

  In addition, according to the fixing device 18 according to the present embodiment, since the activated carbon 29 is included, the apparent hardness of the silicone rubber layer 27 is higher than that of the other portions. Since the diameter φD1 is set smaller than the outer diameter φD2 at the center (φD1 <φD2), the pressure per unit area in the fixing nip formed by the fixing roller 21 and the pressure roller 22 is made uniform in the longitudinal direction, and the toner The image is well fixed on the paper.

  Next, examples of the present invention will be described below together with comparative examples.

In this example, activated carbon having a value obtained by the BET method theory based on the nitrogen adsorption amount of 500 to 2500 m ² / g and a particle size in the range of 1 to 50 μm is 10, 20, and 30% by weight on the end face portions, respectively. The amount of siloxane generated in three types of pressure rollers provided with silicone rubber mixed at a content of 5% was measured, and the results are shown in Table 1 as Examples 1, 2, and 3, respectively. In addition, as a comparative example, the amount of siloxane generated in three types of pressure rollers including silicone rubber mixed at a ratio of 0.5, 40% by weight of activated carbon was measured, and the results are shown in Table 1. The results are shown as Comparative Examples 1, 2, and 3, respectively.

For measurement, each pressure roller is installed in the fixing device of a modified KM-C3232 machine manufactured by Kyocera Mita Co., Ltd., and this modified machine is installed in a chamber made of SUS with a volume of 5 m ³ and ventilated with an air volume of 15 m ³ / h. To do. Then, after ventilation for about 1 hour, printing was performed for 10 minutes, and volatile substances generated from the inside of the apparatus were sampled by a Tenax tube in an amount of 10 ml / min. After that, sampling was continuously performed for about 20 minutes even after printing was stopped. Then, the sampled Tenax tube was desorbed with a heat desorption apparatus, and measurement was performed with GC-MS to calculate the amount of siloxane gas generated.

表１に示す結果から明らかなように、活性炭の含有量が増えるに従ってシロキサンの発生量が減少し、活性炭の吸着作用によって加圧ローラーから放散されるシロキサンの量も明らかに減少している。

As is apparent from the results shown in Table 1, the amount of siloxane generated decreases as the activated carbon content increases, and the amount of siloxane released from the pressure roller by the adsorption action of the activated carbon also clearly decreases.

  Thus, as shown in Comparative Examples 1 and 2 in Table 1, when the activated carbon content is less than 10% by weight, the effect of suppressing the amount of siloxane generated cannot be expected, but the activated carbon content is 30% by weight. If it exceeds 1, not only the performance of the silicone rubber as an elastic body will be lowered, but the tearing strength will be extremely lowered, and the silicone rubber will not be able to withstand the fixing pressure and rotation, and the pressure roller will be damaged.

  Therefore, in order to prevent the decrease in durability of the pressure roller while suppressing the generation amount of siloxane, the content of activated carbon should be set to 10 to 30% by weight.

  In the above description, the present invention is applied to a pressure roller of a fixing device that employs a heating roller method as a fixing method. However, the present invention relates to a fixing device that employs a fixing belt method as a fixing method. The present invention can be similarly applied to the fixing belt shown in FIGS.

  6 is a side view of the fixing belt, FIG. 7 is a cross-sectional view taken along the line BB of FIG. 6, FIG. 8 is an enlarged detail view of a portion C of FIG. It is wound between the drive roller 35 and the driven roller 36 and is rotationally driven by the drive roller 35 in the direction indicated by the arrow. As shown in FIG. 7, the fixing belt 34 is formed by coating a silicone rubber with a thickness of about 500 μm on a polyimide film or an endless core material 37 made of metal such as stainless steel or nickel to form a silicone rubber layer 38. Further, a fluororesin film (PFA tube) 39 is coated thereon.

  Thus, the fixing belt 34 is also not exposed to the fluororesin film 39 of the silicone rubber layer 38 and exposed to the end face portions (width b portion in FIG. 7) 38A at both ends exposed in the width direction (paper passing width direction). Is mixed with activated carbon 29 shown in FIG. That is, in the fixing belt 34, the left and right end surface portions 38A of the silicone rubber layer 38 are made of activated carbon-rich silicone rubber. Here, the content of the activated carbon 29 is set to 10 to 30% by weight for the reason described above.

  Further, in a fixing device that employs a fixing belt method as a fixing method, the end surface portion 38A mixed with the activated carbon 29 of the silicone rubber layer 38 included in the fixing belt 34 is disposed outside the image region (non-image region). The thickness t1 of these end face portions 38A is set to be smaller than the thickness t2 of the central portion (t1 <t2).

  Accordingly, also in the illustrated fixing belt 34, the end surface portion 38A exposed to the outside without being covered with the fluororesin film 39 of the silicone rubber layer 38, that is, the end surface portion 38A in which siloxane which is a volatile organic compound has been diffused conventionally. Since the activated carbon 29 is mixed with the activated carbon 29, the siloxane generated in the silicone rubber is adsorbed by the activated carbon 29, and the siloxane is prevented from being diffused out of the fixing belt 34. In addition, in the fixing belt 34 and the fixing device including the same, the same effects as those obtained in the pressure roller 22 and the fixing device 18 including the same can be obtained.

  In the above, the present invention has been described with respect to a monochrome laser printer, a fixing device provided in the monochrome laser printer, and a fixing member such as a pressure roller and a fixing belt used in the fixing device. Regardless of whether it is a color leather printer or monochrome / color, other image forming apparatuses such as copiers and multi-function machines, fixing devices provided therein, and fixing such as pressure rollers and fixing belts used in the fixing devices Of course, the present invention can be similarly applied to members.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 1A Image forming apparatus main body 2 Image forming part 3 Paper storage part 4 Photosensitive drum 5 Charging device 6 Developing device 7 Transfer roller 8 Cleaning device 9 Toner hopper 10 Laser scanner unit (LSU)
DESCRIPTION OF SYMBOLS 11, 12 Paper feed cassette 13 Pick roller 14 Feed roller 15 Retard roller 16 Paper discharge tray 17 Registration roller 18 Fixing device 19 Conveyance roller 20 Paper discharge roller 21 Fixing roller 22 Pressure roller (fixing member)
23 Fixing heater 24 Fixing roller core metal 25 Fixing roller fluoropolymer 26 Pressure roller core metal (core material)
27 Silicone rubber layer of pressure roller 27A End surface part of silicone rubber layer 27a Liquid silicone rubber rich in activated carbon 27b Liquid silicone rubber not containing activated carbon 28 Fluorine resin film of pressure roller 29 Activated carbon 30 Mold 31 Cylindrical 32 Top Mold 32a Upper mold inlet 33 Lower mold 34 Fixing belt (fixing member)
35 Driving Roller 36 Followed Roller 37 Core Material 38 Silicone Rubber Layer 38A End Surface Portion of Silicone Rubber Layer 39 Fluororesin Film of Fixing Belt S1 First Conveying Path S2 Second Conveying Path

Claims (7)

In a fixing device comprising a fixing member formed by forming a silicone rubber layer on a core material and coating a fluororesin film on the outer surface of the silicone rubber layer,
Activated carbon is mixed with the end face exposed to the outside without being covered with the fluororesin film of the silicone rubber layer ,
A fixing device wherein the outer diameter or the outer diameter or the central portion of the thickness of the end face portion of the activated carbon is mixed in the silicone rubber layer included in the fixing member is set smaller than the thickness. The fixing device according to claim 1, wherein a content of the activated carbon is set to 10 to 30% by weight. A method for producing a fixing member comprising: forming a silicone rubber layer on a core material; and coating the outer surface of the silicone rubber layer with a fluororesin film,
A liquid silicone rubber mixed with activated carbon is poured into the space between the core material and the fluororesin film of a vertical mold in which the core material and the fluororesin film are inserted and set in advance by a predetermined height. In addition, liquid silicone rubber containing no activated carbon or containing less activated carbon than the end portion is poured by a predetermined height, and liquid silicone rubber mixed with activated carbon is further poured by a predetermined height. And then vulcanizing the resin while maintaining the condition. A fixing device comprising the fixing member manufactured by the manufacturing method according to claim 3 . The fixing device according to claim 4, wherein an outer diameter or a thickness of an end surface portion where the activated carbon of the silicone rubber layer included in the fixing member is mixed is set smaller than an outer diameter or a thickness of the central portion. 6. The fixing device according to claim 1, wherein an end face portion mixed with activated carbon of the silicone rubber layer included in the fixing member is disposed outside an image area. An image forming apparatus comprising: a fixing device according to any one of claims 1,2,4～6.

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