JP2005078019A - Fixing member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing member which is excellent in fixability and durability. <P>SOLUTION: The fixing member is composed of: a substrate 1_1; an elastic layer 1_2 composed of heat-resistant elastomer and layered on the substrate 1_1; and a surface layer 1_3 mainly constituted of silicone resin and layered on the elastic layer 1_2. Two fixing members are arranged facing each other across a recording medium carrying an unfixed toner image so as to thermally fix the unfixed toner image on the recording medium by heating and pressurizing, and regarding at least one of the two fixing members, the fixing member satisfies a condition of 0.8×H≤D≤3.5×H when the film thickness of the elastic layer 1_2 is defined as D(μm) and the hardness is defined as H(degree). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fixing member used in a fixing device that thermally fixes an unfixed toner image in an image forming apparatus such as an electrophotographic copying machine, an electrostatic recording apparatus, a printing machine, or a printer.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as an electrophotographic copying machine, an electrostatic recording apparatus, a printing machine, or a printer, unfixed at a nip portion formed by a pair of fixing members composed of a belt or a roller arranged opposite to each other. 2. Description of the Related Art A fixing device that heats and pressurizes a recording medium carrying a toner image and heat-fixes is widely used.

  When heat fixing is performed by such a fixing device, an unfixed toner image on the recording medium is thermally fixed in accordance with the irregularities on the surface of the recording medium. Need to use. The elasticity of the fixing member is an important factor in increasing the fixing speed.

  Such a fixing member is required to have good releasability in addition to elasticity, that is, the fixing member and the recording medium are easily separated when thermal fixing is completed at the nip portion. Conventionally, an elastic body of silicone rubber has been widely used as the surface layer of the fixing member in order to give the fixing member good release properties.

  However, if the silicone rubber is used as it is as the surface layer of the fixing member, re-crosslinking proceeds when the silicone rubber is heated at the nip portion, or it becomes brittle or deteriorates due to thermal oxidation, so that it can be released. There is a problem that the reliability of the fixing device is lowered.

  Further, the silicone oil applied to the surface of the fixing member as a release agent causes a problem that the silicone rubber swells and changes the outer diameter of the fixing member, which adversely affects the fixed image.

  In addition, recently, there has been an example in which a release agent is imparted to a fixing member via a developer by adding a wax to the developer without using silicone oil as a release agent. In this case, there is a problem that the wax adheres to the surface of the silicone rubber and the releasability is lowered.

  Further, when both the surface layer of the fixing member for heating and the surface layer of the fixing member for pressure are made of an elastic body such as silicone rubber, the friction coefficient becomes too high, which may be a problem. In order to reduce the friction coefficient, a method of roughening the surface has been proposed. However, when the surface is roughened, there is a problem that the gloss of the fixed image is reduced.

  As described above, the fixing member is required to have sufficient elasticity, releasability, slipperiness, printing durability, and the like. The material satisfying these requirements is not a single material, but a multi-layer structure in which a fluororesin layer or a silicone resin layer is coated on a rubber layer such as silicone rubber as an elastic layer, and each of the plurality of layers has the above-described structure. The various characteristics are shared.

  However, in the method of coating the fluororesin layer on the rubber layer as the elastic layer, since the firing temperature of the fluororesin must be increased, the underlying elastic layer may be deteriorated, and the resin layer is laminated by coating. There is a problem with the method.

  In addition, there has been proposed a method in which a fluororesin tube is laminated on a fixing member by heat shrinking, and there is an example that has been realized. However, it is difficult to realize when the size of the fixing member is large.

  Further, a heat fixing roller is disclosed in which a silicone varnish solution is applied on an elastic layer and dried to form a silicone resin coating layer (see, for example, Patent Document 1), and a roller made of a cylindrical elastomer A fixing roller having a core layer and a roller surface layer composed of a thin layer of a silicone resin baked on the surface thereof is disclosed (see Patent Document 2).

  Further, a fixing member in which a surface layer made of a silicone resin is provided on a rubber layer is disclosed (for example, see Patent Document 3).

Further, as a fixing member, a fixing film using a material containing fluorinated polyimide as a main component, and an outermost layer and / or an innermost layer using a material containing fluorinated polyimide as a main component, and an intermediate layer with silicone rubber or / and A fixing device using a fixing film using fluororubber is disclosed (for example, see Patent Document 4).
JP-A-62-255981 (pages 1 to 3, FIG. 1) JP 58-11976 (pages 1 and 2, Fig. 1) Japanese Patent Publication No. 8-30926 (pages 1 to 3 and FIG. 1) Japanese Patent Laid-Open No. 9-274402 (pages 2 and 3, FIG. 1)

  However, the fixing rollers of Patent Document 1 and Patent Document 2 have a problem that the shrinkage rate of the silicone resin is smaller than that of rubber, and wrinkles or cracks are likely to occur due to shrinkage of the base rubber layer. However, although the life of up to 50,000 sheets has been confirmed in the method of Patent Document 3, this life is still insufficient, and in this method, cracks occur when fixing thick paper. There are problems such as.

  Further, even with the fixing device of Patent Document 4, sufficient elasticity and releasability cannot be obtained, and a highly durable fixing member that does not generate wrinkles or cracks over a long period of time is obtained. It is not possible.

  In view of the above circumstances, an object of the present invention is to provide a fixing member having excellent fixing properties and durability.

The fixing member of the present invention that achieves the above object is
A recording medium comprising a substrate, an elastic layer made of a heat-resistant elastomer laminated on the substrate, and a surface layer mainly composed of a silicone resin laminated on the elastic layer, and carrying an unfixed toner image At least one fixing member of two fixing members that are disposed opposite to each other and thermally fixed by heating and pressurizing an unfixed toner image on the recording medium,
When the fixing member has a thickness of the elastic layer as D (μm) and the hardness of the elastic layer as H (degrees),
0.8 × H ≦ D ≦ 3.5 × H
It is characterized by satisfying the following conditions.

  The hardness H of the elastic layer is JIS A hardness, more specifically, type A durometer hardness of “Durometer hardness test” defined in JIS K 6253 “Hardness test method of vulcanized rubber and thermoplastic rubber”. Say it.

  According to the fixing member of the present invention, since the hardness H and the film thickness D of the elastic layer satisfy the above conditions, a fixing member excellent in fixing property and durability can be realized.

Here, the fixing member is
0.8 × H ≦ D ≦ 3.5 × H
Instead of
0.9 × H ≦ D ≦ 3 × H
It is preferable that the following conditions are satisfied.

Further, the fixing member is
0.8 × H ≦ D ≦ 3.5 × H
Instead of
0.9 × H ≦ D ≦ 2.5 × H
It is preferable that the following conditions are satisfied.

  The elastic layer preferably has a hardness of 10 degrees or more and 70 degrees or less.

  Furthermore, it is preferable that the elastic layer has a hardness of 15 degrees or more and 55 degrees or less.

  Furthermore, it is preferable that the elastic layer has a hardness of 20 degrees or more and 50 degrees or less.

  Moreover, it is preferable that the said elastic layer has a film thickness of 5 micrometers or more and 350 micrometers or less.

  Furthermore, it is preferable that the elastic layer has a thickness of 10 μm or more and 300 μm or less.

  Furthermore, it is preferable that the elastic layer has a thickness of 30 μm or more and 200 μm or less.

  The base is preferably an endless belt.

  Moreover, it is preferable that the said base | substrate is what has a polyimide as a main component.

  Moreover, it is preferable that the said base | substrate has a thickness of 20 micrometers or more and 200 micrometers or less.

  Furthermore, it is preferable that the substrate has a thickness of 30 μm or more and 150 μm or less.

  Furthermore, it is preferable that the substrate has a thickness of 40 μm or more and 100 μm or less.

  Moreover, it is preferable that the said surface layer has a film thickness of 1 micrometer or more and 30 micrometers or less.

  Furthermore, the surface layer preferably has a film thickness of 10 μm or more and 20 μm or less.

  Further, the surface layer preferably has a breaking elongation of 5% or more.

  Further, it is preferable that the fixing member has an adhesive layer interposed between the base and the elastic layer.

  As described above, according to the fixing member of the present invention, it is possible to realize a fixing member having excellent fixability and durability.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 is a schematic configuration diagram of an image forming apparatus in which the fixing member of this embodiment is used.

  FIG. 1 shows a schematic configuration of an electrophotographic copying machine 100.

  The copying machine 100 includes a photosensitive drum 6, a scorotron 7, an exposure device 8, a developing device 9, an intermediate transfer belt 10, a primary transfer roll 11, a photosensitive member cleaning unit 12, a secondary transfer roll 13, a paper feed cassette 14, An intermediate transfer belt cleaning unit 15, a fixing device 20, a discharge tray 30, and the like are provided.

  The copying machine 100 is a so-called full-color copying machine, and a developing device 9 develops a latent image with toners of yellow (Y), magenta (M), cyan (C), and black (K), respectively. Containers 9Y, 9M, 9C and 9K are provided.

  Next, the operation of the copying machine 100 will be described.

  The photosensitive drum 6 rotates in the direction of arrow A, and the surface of the photosensitive drum 6 is charged to a predetermined potential by the scorotron 7. Next, the exposure device 8 exposes the surface of the photosensitive drum 6 with exposure light corresponding to image information. A latent image is formed. Next, the latent image on the photosensitive drum 6 is developed with toner by the developing device 9 to form a toner image. The toner image on the photosensitive drum 6 is primarily transferred by the primary transfer roll 11 onto the intermediate transfer belt 10 that circulates in the direction of arrow B.

  The toner image transferred onto the intermediate transfer belt 10 is secondarily transferred to the recording paper 16 conveyed from the paper feed cassette 14 by the secondary transfer roll 13, and the recording paper 16 that has received the transfer is transferred to the recording paper conveyance belt. 17 to the fixing device 20. The unfixed toner image on the recording paper 16 is heat-fixed by being heated and pressed by the fixing device 20. The recording paper 16 after fixing is discharged to the discharge tray 30.

  The toner remaining on the photosensitive drum 6 after the primary transfer is removed by the photosensitive member cleaning unit 12. Further, the toner remaining on the intermediate transfer belt 10 after the secondary transfer is removed by the intermediate transfer belt cleaning unit 15.

  FIG. 2 is a schematic configuration diagram of the fixing device provided in the copying machine shown in FIG.

  As shown in FIG. 2, the fixing device 20 includes a heating roll 21 and a heating roll 21 which are arranged to face each other with a recording paper 16 carrying an unfixed toner image interposed therebetween and rotate in the directions of arrows D and E, respectively. A pressure roll 22, an endless belt 23 that circulates in the direction of arrow C, a peeling roll 24 that peels the recording paper 16 from the endless belt 23, a tension roll 25 that applies a predetermined tension to the endless belt 23, and the recording paper 16 A heat sink 26 that absorbs the heat of the endless belt 23 and a ventilation duct 27 that radiates the heat of the heat sink 26 are provided.

  The recording paper 16 is inserted into the nip portion N formed by the heating roll 21 and the pressure roll 22 of the fixing device 20, and the unfixed toner image on the recording paper 16 is heated and pressed by the nip portion N. The unfixed toner image is heat-fixed on the recording paper 16 to complete a fixed image.

  The fixing member of the present invention is used as the endless belt 23 of the fixing device 20.

  FIG. 3 is a schematic configuration diagram showing an embodiment of a fixing member of the present invention.

  As shown in FIG. 3, the fixing member 1 is mainly composed of a base 1_1, an elastic layer 1_2 made of a heat-resistant elastomer laminated on the base 1_1, and a silicone resin laminated on the elastic layer 1_2. And the surface layer 1_3.

  The shape of the fixing member 1 may be any shape suitable for the image forming apparatus to be used, and can be appropriately selected from a sheet shape, a belt shape, a drum shape, and the like, but an endless belt shape is particularly preferable. is there.

  The substrate 1_1 is required to have sufficient heat resistance and mechanical strength, and is made of a metal sheet such as nickel, aluminum or stainless steel, or a resin film such as PET (polyethylene terephthalate), PBT (polybutylene terephthalate), polyimide or polyimide amide. Although it can be used, a polyimide resin film is particularly preferable. The polyimide resin may be one whose volume resistivity is controlled by adding and dispersing conductive powder or the like, or an endless belt-like polyimide belt whose volume resistivity is controlled by adding and dispersing carbon black may be used. it can. Furthermore, it is also possible to use a long polyimide sheet having both end portions combined in a puzzle shape and thermocompression bonded using a thermocompression bonding member to finish it in an endless belt shape.

  The thickness of the substrate 1_1 is preferably in the range of 20 μm to 200 μm, more preferably in the range of 30 μm to 150 μm, and still more preferably in the range of 40 μm to 100 μm. If the thickness of the substrate 1_1 is less than 20 μm, the dimensional stability and strength during heating and cooling are insufficient, and if the thickness of the substrate 1_1 exceeds 200 μm, the specific heat of the fixing member increases and the amount of heat transfer decreases. This is not preferable because it leads to a decrease in transfer speed and cycle time.

  The elastic layer 1_2 is required to have elasticity and heat resistance, and silicone rubber, fluorine rubber, or the like is preferably used as such a material. These rubbers are not particularly limited, and include well-known methyl silicone rubbers, methyl phenyl silicone rubbers, methyl vinyl silicone rubbers, fluorine-containing silicone rubbers such as one-component and two-component condensation polymerization types and addition polymerization types. Etc. are used.

  From the viewpoint of the method of forming the rubber layer, the rubber layer can be made into a solution (liquid) that can be applied, such as a rubber dissolved in a solvent or a solvent-free type (liquid rubber). It is preferable that one-component condensation type liquid silicone rubber, one-component addition type liquid silicone rubber, two-component addition type liquid silicone rubber, and the like are suitably used.

  The hardness of the elastic layer 1_2 is preferably in the range of 10 degrees to 70 degrees in terms of JIS A hardness, more preferably in the range of 15 degrees to 55 degrees, and still more preferably in the range of 20 degrees to 50 degrees. When the hardness of the elastic layer 1_2 is 10 degrees or less, there is a problem in that the strength of the belt is lowered and durability is deteriorated, and adhesion with the surface layer 1_3 is difficult. When the hardness of the elastic layer 1_2 exceeds 70 degrees, there arises a problem that when the surface property of the recording paper is poor, the adhesion with the recording paper is lowered and fixing becomes incomplete. When the hardness of the elastic layer 1_2 is in the range of 20 degrees or more and 50 degrees or less, it is preferable in terms of belt strength, adhesiveness to the surface layer 1_3, and fixability, and also from the viewpoint of obtaining excellent reliability.

  The thickness of the elastic layer 1_2 is preferably in the range of 5 μm to 350 μm, more preferably in the range of 10 μm to 300 μm, and still more preferably in the range of 30 μm to 200 μm. When the film thickness of the elastic layer 1_2 is less than 5 μm, the elasticity is insufficient and the effect of providing the rubber layer is lost, which causes a problem in fixability. If the thickness of the elastic layer 1_2 exceeds 350 μm, the specific heat increases and the amount of heat transfer decreases, leading to a decrease in fixing speed, and the temperature of the base 1_1 and the elastic layer 1_2 near the heat source becomes too high. There is a problem that the lifetime is shortened due to deterioration.

  The film thickness and hardness of the elastic layer 1_2 are not independent, and satisfy the following conditions when the film thickness of the elastic layer 1_2 is D (μm) and the hardness of the elastic layer 1_2 is H (degrees). There is a need.

0.8 × H ≦ D ≦ 3.5 × H
The film thickness D and hardness H of the elastic layer 1_2 are
Instead of
0.9 × H ≦ D ≦ 3 × H
It is more preferable to satisfy the following conditions.

Furthermore, the film thickness D and hardness H of the elastic layer 1_2 are
0.8 × H ≦ D ≦ 3.5 × H
Instead of
0.9 × H ≦ D ≦ 2.5 × H
It is more preferable to satisfy the following conditions.

  When the film thickness D of the elastic layer 1_2 is 0.8 × H or less, the elasticity of the fixing member is insufficient, and the fixing is not sufficiently performed without being able to cope with the unevenness of the recording paper, and the minute portion of the image is sufficient. Gloss uniformity cannot be obtained.

  When plain paper is used as the recording paper, if the film thickness D of the elastic layer 1_2 is 0.8 × H or more, the image fixed on the recording paper has a level with no problem with respect to gloss uniformity.

  When thick paper is used as the recording paper, if the film thickness D of the elastic layer 1_2 is 0.9 × H or more, the image fixed on the recording paper has a level with no problem with respect to gloss uniformity.

  On the other hand, when the film thickness D of the elastic layer 1_2 exceeds 3.5 × H, the surface layer 1_3 cannot respond to the shrinkage of the elastic layer 1_2 during pressurization, and wrinkles due to insufficient adhesion occur, or continuous fixing. At times, problems such as the fixing property gradually lowering occur. When the thickness D of the elastic layer 1_2 is 3.5 × H or less, no wrinkle is generated even when a recording paper having a thickness of 100 μm or less is used.

  Note that when the thickness D of the elastic layer 1_2 is 3 × H or less, wrinkles do not occur even when a thick paper having a thickness of 200 μm or more is used as the recording paper.

  Further, when the thickness D of the elastic layer 1_2 is 2.5 × H or less, the heat capacity of the belt is reduced, so that the temperature of the heat source can be further lowered and the fixing time is shortened so that high speed is achieved. Further advantages such as realization of the fixing device can be obtained.

  The surface layer 1_3 is made of a silicone resin and has characteristics such as heat resistance, releasability from the toner, and low frictional resistance with the elastic body.

  The thickness of the surface layer 1_3 is preferably 1 μm or more and 30 μm or less, and more preferably 10 μm or more and 20 μm or less. When the film thickness of the surface layer 1_3 is less than 1 μm, the surface layer is easily affected by the surface shape of the underlying elastic layer, which may cause a problem such as the occurrence of the surface layer repelling. When the film thickness of the surface layer 1_3 is 1 μm or more, it is possible to reduce the repelling by smoothing the surface property of the underlying elastic layer. Furthermore, when the film thickness of the surface layer 1_3 is set to 10 μm or more, it can be made less susceptible to the surface property of the underlying elastic layer, so that productivity is improved and the repellency is reduced to a level at which there is no problem in image quality. In addition, there can be obtained an advantage that film thickness unevenness can be reduced.

  On the other hand, when the film thickness of the surface layer 1_3 exceeds 30 μm, the elastic action effect by the underlying elastic layer is reduced and the fixing is liable to be poorly fixed. However, when the thickness of the surface layer 1_3 is 30 μm or less, such a problem can be avoided. Further, when the film thickness of the surface layer 1_3 is set to 20 μm or less, the fixing property is good even when a recording paper with poor surface properties is used, so that there is an advantage that cracks do not occur even when the thick paper is used as the recording paper. can get.

  Next, the elongation at break of the surface layer 1_3 will be described. When thin paper having a thickness of about 100 μm is used as the recording paper, there is no problem even if the elongation at break of the surface layer 1_3 is 5% or less. However, when the thick paper having a thickness exceeding 200 μm is used as the recording paper, Since the deformation does not respond to the shrinkage of the underlying elastic layer and causes problems such as poor adhesion and cracks, the elongation at break of the surface layer 1_3 is preferably 5% or more.

  Next, another embodiment of the present invention will be described.

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

  As shown in FIG. 4, the fixing member 2 includes a base 2_1, an adhesive layer 2_2 laminated on the base 2_1, an elastic layer 2_3 made of a heat-resistant elastomer laminated on the adhesive layer 2_2, and an elastic layer. And a surface layer 2_4 mainly composed of a silicone resin laminated on 2_3.

  The adhesive layer 2_2 is a layer for improving the adhesion between the base 2_1 and the elastic layer 2_3, and is not essential for the fixing member of the present invention, but is effective for enhancing the durability of the fixing member. Therefore, it is preferable to interpose the adhesive layer 2_2 between the base 2_1 and the elastic layer 2_3 as necessary.

  The base 2_1, the elastic layer 2_3, and the surface layer 2_4 are the same as the base 1_1, the elastic layer 1_2, and the surface layer 1_3 illustrated in FIG.

  As the adhesive layer 2_2, primers or the like usually used for adhesion of silicone rubber can be applied. Examples of the primers include, but are not limited to, aminosilane coupling agents, chlorosilane coupling agents, chloromethylsilane coupling agents, cyanosilane coupling agents, titanate coupling agents, and the like. It is not something. Of these, aminosilane coupling agents and titanate coupling agents are preferably used.

  Next, examples of the present invention will be described.

Toray Dow Corning on a polyimide belt-like substrate with a circumference of 527.8 mm, a width of 420 mm, and a thickness of 75 μm, with carbon black added and volume resistivity adjusted to Rv = 10 ¹² Ω · cm -After applying DY39-115, which is a silicone rubber primer manufactured by Silicone Co., Ltd., after air-drying for 30 minutes, a coating film was formed by dip coating a coating solution prepared with a silicone rubber precursor and n-hexane. The obtained sample was subjected to primary vulcanization at 120 ° C. for 10 minutes, and then a surface layer having a thickness of 10 μm was formed by dip coating with SR2316 solution manufactured by Toray Dow Corning Silicone Co., Ltd., and 120 ° C. for 10 minutes. Primary vulcanization, secondary vulcanization at 180 ° C. for 4 hours was performed to obtain an endless belt-like fixing member. The elongation at break of the surface layer material was 6%.

  As shown in Table 1, the hardness of the silicone rubber applied at this time is six types of 15 degrees, 20 degrees, 24 degrees, 47 degrees, 58 degrees, and 66 degrees. The thickness of the elastic layer was changed from 40 μm to 200 μm.

  This fixing member is mounted on a copying machine (see FIG. 1) in which the fixing unit of the Fuji Xerox copier DocuCenterColor500 (DCC500) is modified to the belt-type fixing device shown in FIG. A full-color image was formed using the developer.

After passing 200,000 sheets of plain paper having a thickness of 80 μm as recording paper, a test for passing 1,000 sheets of 250 μm thick paper was performed,
(1) Whether the fixing member is durable (whether there is a scratch on the surface of the fixing member after passing the paper, or whether there is peeling between the surface layer and the elastic layer),
(2) Whether or not the surface layer is cracked,
(3) Whether or not the quality of the fixed image was good was evaluated, and the results were represented by ○ mark, Δ mark, and X mark in order of high evaluation.

  For the fixing member for which all the results were ○ in this test, 200 sheets were continuously passed using a test apparatus modified so that image quality evaluation at high speed (process speed 600 mm) was possible. It was evaluated whether or not the fixing was performed satisfactorily.

  The evaluation results are shown in Table 1. The hardness (JIS A) represents a type A durometer hardness according to JIS K 6253.

  As shown in Table 1, a fixing member having a hardness of the elastic layer of 24 degrees and a film thickness of 60 μm (D / H = 1.21), a fixing member having a hardness of the elastic layer of 47 degrees and a film thickness of 80 μm (D / H = 1.70) and the fixing member (D / H = 2.50) having an elastic layer hardness of 60 degrees and a film thickness of 80 μm, all the durability, wrinkles, cracks, image quality, etc. of both plain paper and cardboard The evaluation was ○, and the image quality at high speed was also ○.

  In the case of a fixing member having an elastic layer hardness of 15 degrees and a film thickness of 40 μm (D / H = 2.67) and an elastic layer having a hardness of 47 degrees and a film thickness of 120 μm (D / H = 2.55) Also good evaluation was obtained. However, the image quality at high speed of these fixing members was Δ.

  In the case of a fixing member (D / H = 0.83) having an elastic layer hardness of 24 degrees and a film thickness of 20 μm, and a fixing member having an elastic layer hardness of 47 degrees and a film thickness of 40 μm (D / H = 0.85) The following favorable evaluation was obtained.

  A fixing member was prepared and evaluated in the same manner as in Example 1 except that a fixing member having a breaking elongation of 2% for the surface layer was used. The results are shown in Table 2.

  As shown in Table 2, a fixing member (D / H = 0.83) with a hardness of the elastic layer of 24 degrees and a film thickness of 20 μm (D / H = 0.83), a fixing member with a hardness of the elastic layer of 24 degrees and a film thickness of 60 μm (D / H = 0.25), a fixing member having an elastic layer hardness of 47 degrees and a film thickness of 40 μm (D / H = 0.85), an elastic layer having a hardness of 47 degrees and a film thickness of 80 μm (D / H = 1. 70), a fixing member having a hardness of the elastic layer of 47 degrees and a film thickness of 120 μm (D / H = 2.55), and a fixing member having a hardness of the elastic layer of 66 degrees and a film thickness of 80 μm (D / H = 1.21). In the case of), relatively good results were obtained with plain paper, but not so good with cardboard.

  Using a silicone rubber precursor with a rubber hardness of 66 degrees, adjusting the coating conditions so that the film thickness of the elastic layer is 80 μm, using SR2316 as the surface layer material, the film thickness of the surface layer is 0.8 μm, 1 μm, The fixing member was prepared by adjusting to 5 μm and evaluated for the presence or absence of repelling.

  When the film thickness of the surface layer was 0.8 μm and 1 μm, a lot of repelling occurred and the surface state was not able to withstand image evaluation.

  When the surface layer thickness was 5 μm, the number of repelling was small, and two of the ten fixing members produced had no repelling.

  A fixing member was prepared in the same manner as in Example 3 except that the rubber was subjected to primary vulcanization and then the surface was polished with No. 4000 sandpaper to smooth the surface, and the presence or absence of repelling was evaluated.

  When the surface layer thickness was 0.8 μm, repelling occurred.

  One of the 10 fixing members having a surface layer thickness of 1 μm was not repelled.

  There were no repelling of 10 fixing members with a surface layer thickness of 5 μm.

  Using a silicone rubber precursor with a rubber hardness of 47 degrees, adjusting the coating conditions so that the film thickness of the elastic layer is 80 μm, using SR2316 as the surface layer material, the film thickness of the surface layer is 20 μm, 30 μm, and 35 μm A fixing member was prepared by adjusting so that the image quality was evaluated. The results are shown in Table 3.

  As shown in Table 3, when the surface layer thickness was 20 μm, all evaluation results such as durability, wrinkles, cracks, image quality, etc. were marked with ○ for both plain paper and cardboard.

  In the case of the surface layer thickness of 30 μm, evaluation of wrinkles, cracks, image quality, etc. was not good on the thick paper, but all evaluation results were marked with ○ on the plain paper.

  In the case of the surface layer thickness of 35 μm, the evaluation of the image quality of plain paper was further reduced.

1 is a schematic configuration diagram of an image forming apparatus in which a fixing member according to an exemplary embodiment is used. FIG. 2 is a schematic configuration diagram of a fixing device provided in the copying machine shown in FIG. 1. It is a schematic block diagram which shows one Embodiment of the member for fixing of this invention. It is a schematic block diagram which shows other embodiment of the member for fixing of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixing member 1_1 Base body 1_2 Elastic layer 1_3 Surface layer 2 Fixing member 2_1 Base body 2_2 Adhesive layer 2_3 Elastic layer 2_4 Surface layer 6 Photosensitive drum 7 Scorotron 8 Exposure device 9 Developing device 9Y, 9M, 9C, 9K Developer 10 Intermediate Transfer belt 11 Primary transfer roll 12 Photoconductor cleaning unit 13 Secondary transfer roll 14 Paper feed cassette 15 Intermediate transfer belt cleaning unit 16 Recording paper 17 Recording paper transport belt 20 Fixing device 21 Heating roll 22 Pressure roll 23 Endless belt 24 Peeling roll 25 Tension roll 26 Heat sink 27 Ventilation duct 30 Discharge tray 100 Copying machine

Claims (18)

A recording medium comprising a substrate, an elastic layer made of a heat-resistant elastomer laminated on the substrate, and a surface layer mainly composed of a silicone resin laminated on the elastic layer, and carrying an unfixed toner image At least one fixing member of two fixing members that are arranged opposite to each other and that are thermally fixed by heating and pressurizing an unfixed toner image on the recording medium,
When the fixing member has a thickness of the elastic layer as D (μm) and a hardness of the elastic layer as H (degrees),
0.8 × H ≦ D ≦ 3.5 × H
A fixing member characterized by satisfying the following conditions. The fixing member is
0.8 × H ≦ D ≦ 3.5 × H
Instead of
0.9 × H ≦ D ≦ 3 × H
The fixing member according to claim 1, wherein the following condition is satisfied. The fixing member is
0.8 × H ≦ D ≦ 3.5 × H
Instead of
0.9 × H ≦ D ≦ 2.5 × H
The fixing member according to claim 1, wherein the following condition is satisfied.   The fixing member according to any one of claims 1 to 3, wherein the elastic layer has a hardness of 10 degrees or more and 70 degrees or less.   The fixing member according to claim 1, wherein the elastic layer has a hardness of 15 degrees to 55 degrees.   The fixing member according to claim 1, wherein the elastic layer has a hardness of 20 degrees or more and 50 degrees or less.   The fixing member according to claim 1, wherein the elastic layer has a film thickness of 5 μm to 350 μm.   The fixing member according to claim 1, wherein the elastic layer has a thickness of 10 μm or more and 300 μm or less.   The fixing member according to claim 1, wherein the elastic layer has a thickness of 30 μm or more and 200 μm or less.   The fixing member according to claim 1, wherein the base is an endless belt.   The fixing member according to claim 10, wherein the base is mainly composed of polyimide.   The fixing member according to claim 10, wherein the substrate has a thickness of 20 μm to 200 μm.   The fixing member according to claim 10, wherein the substrate has a thickness of 30 μm to 150 μm.   The fixing member according to claim 10, wherein the substrate has a thickness of 40 μm to 100 μm.   The fixing member according to claim 10, wherein the surface layer has a thickness of 1 μm to 30 μm.   The fixing member according to claim 10, wherein the surface layer has a thickness of 10 μm to 20 μm.   The fixing member according to claim 10, wherein the surface layer has a breaking elongation of 5% or more.   The fixing member according to claim 10, wherein an adhesive layer is interposed between the base and the elastic layer.

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