fixing pad

Abstract

The present application is a fixing pad. The fixing pad (10) of the present application has a base material (11); and a sliding layer (13) provided on a main surface (11a) of the base material (11); wherein the sliding layer (13) is a woven fabric or a knitted fabric containing fluorine fibers and / or glass fibers, and a surface roughness Ra of a sliding surface (13a) of the sliding layer (13) is 12.0 μm or less.

Description

TECHNICAL FIELD

[0001] The present application relates to a fixing pad. BACKGROUND

[0002] In an image forming apparatus, a fixing device is provided which heats and presses toner transferred to a recording medium, thereby fixing the toner to the recording medium. In the past, the fixing device has heated a loop-shaped belt wound around a fixing roller, and pressed the recording medium on which the toner is transferred between the fixing roller and a pressure roller opposed to the fixing roller, thereby melting the toner and fixing the toner.

[0003] In recent years, a fixing device using a fixing pad instead of a fixing roller, and fixing by a fixing belt provided between the fixing pad and a pressure roller has been attracting attention. For example, in Patent Literature 1, a structure is disclosed in which a textile fabric composed of a fluorine fiber or the like is wound around a surface of a sliding member in parallel to a sliding direction.

[0004] PRIOR ART

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent No. 6481606 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, from the viewpoint of heat conductivity and low friction with the fixing belt, the sliding surface of the sliding member is preferably smooth. However, in the above-described Patent Literature 1, since the textile fabric is wound and fixed in the sliding direction of the sliding member, the smooth surface cannot be maintained due to misalignment of the textile fabric, and there is a concern that the image quality will decrease over time.

[0009] The present application has been achieved in view of the above-described problems, and an object thereof is to provide a fixing pad having a smooth sliding surface, and capable of fixing toner well.

[0010] MEANS OF SOLVING THE PROBLEMS

[0011] An embodiment of the present application is a fixing pad having: a base material; and a sliding layer provided on a main surface of the base material; wherein the sliding layer is a textile fabric or a woven fabric containing a fluorine fiber and / or a glass fiber, and a surface roughness Ra of a sliding surface of the sliding layer is 12.0 μm or less.

[0012] The thickness of the sliding layer is preferably 300 μm or more and 1000 μm or less.

[0013] The base material and the sliding layer are preferably bonded using an adhesive.

[0014] The sliding layer is preferably provided on the entire surface of the main surface of the base material.

[0015] The cross-sectional shape in the transverse direction of the base material is preferably a U shape or a circular arc shape.

[0016] Inventive Effects

[0017] The fixing pad according to the present application has a smooth sliding surface and can fix toner well. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic cross-sectional view showing one embodiment of the fixing pad of the present application.

[0019] Figure 2 is a schematic cross-sectional view showing a toner fixing device provided with the fixing pad of the present application.

[0020] Figure 3 is a schematic cross-sectional view showing another embodiment of the fixing pad of the present application.

[0021] Figure 4 is a schematic cross-sectional view showing one example of an image forming apparatus provided with the fixing pad of the present application.

[0022] EXPLANATION OF REFERENCE NUMERALS

[0023] 10 fixing pad

[0024] 11 base material

[0025] 11a main surface

[0026] 12 adhesive

[0027] 13 sliding layer

[0028] 13a sliding surface

[0029] 20 toner fixing device

[0030] 21 fixing belt

[0031] 22 heating device

[0032] 23 pressure roller

[0033] 24 shaft body

[0034] 25 elastic body

[0035] 26 covering layer

[0036] 27 housing

[0037] 28 opening

[0038] 30 image forming apparatus

[0039] 31 image bearing member

[0040] 32 charging roller

[0041] 33 exposure unit

[0042] 34 transfer roller

[0043] 35 cleaning roller for image bearing member

[0044] 36 recording medium

[0045] 40 developing unit

[0046] 42 developer

[0047] 43 developer supply unit

[0048] 44 developer bearing member

[0049] 45 developer regulating member DETAILED DESCRIPTION

[0050] Hereinafter, embodiments of the present application will be described in detail with reference to the accompanying drawings. However, the following embodiments are shown for exemplary purposes, and the present application is not limited to the embodiments shown below.

[0051] [Fixing pad]

[0052] The fixing pad of one embodiment of the present application is a fixing pad 10 arranged opposite to the pressure roller 23 in the toner fixing device 20 (refer to Figure 2 ).

[0053] The fixing pad 10 will be described with reference to Figure 1 . Figure 1 is a sectional view of the fixing pad 10 in a direction (lateral direction X) orthogonal to the longitudinal direction Y. As shown in Figure 1 , the fixing pad 10 includes a base material 11 and a sliding layer 13 provided on a main surface 11a of the base material 11. The base material 11 and the sliding layer 13 are bonded with an adhesive 12. The main surface 11a of the base material 11 is a surface on the opposite side to the pressure roller 23.

[0054] Hereinafter, each structure will be described in detail.

[0055] (Base material)

[0056] The base material 11 can use aluminum (including aluminum alloy), copper, iron, stainless steel, brass, sulfur free-cutting steel (SUM), and a material in which nickel or zinc is plated on the surface of these metals. From the viewpoint of thermal conductivity, aluminum or copper is preferable.

[0057] The substrate 11 may be made of one material or two or more materials. In addition, the substrate 11 may be a laminated structure.

[0058] To improve the adhesion between the adhesive 12 and the substrate 11, a primer layer can be provided between the substrate 11 and the adhesive 12.

[0059] The cross-section of the substrate 11 in the transverse direction X can be U-shaped or as shown in the figure. Figure 3 The arc shape shown. Figure 1 The substrate 11 shown is in contact with the pressure roller 23 (see reference). Figure 2 The area forming the roller gap can be flat, but it can also be curved. Since the cross-section of the substrate 11 in the transverse direction X is U-shaped or arc-shaped, the fixing belt 21 will not get caught on the corner of the fixing pad 10 and can slide well.

[0060] The length of the substrate 11 in the longitudinal direction Y is not particularly limited and can be appropriately adjusted according to the form of the image forming apparatus. For example, the length of the substrate 11 in the longitudinal direction Y is preferably 200 mm or more and 400 mm or less, and more preferably 250 mm or more and 370 mm or less.

[0061] The transverse direction X of the substrate 11 is not particularly limited and can be appropriately adjusted according to the form of the image forming apparatus. For example, the transverse direction X of the substrate 11 is preferably 8 mm or more and 30 mm or less, and more preferably 15 mm or more and 25 mm or less.

[0062] From the viewpoint of strength and thermal conductivity, the thickness of the substrate 11 is preferably 0.2 mm or more and 1.0 mm or less, more preferably 0.3 mm or more and 0.6 mm or less.

[0063] (Adhesive)

[0064] From the viewpoint of ensuring good adhesion between the sliding layer 13 and the substrate 11, the adhesive 12 is preferably a one-component curable rubber. More preferably, it is a one-component liquid silicone rubber or a one-component silicone RTV rubber.

[0065] Commercially available products include: KE-1880 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), KE-1833 (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), and TSE322 (manufactured by Momentive Japan Co., Ltd.).

[0066] The bonding of the substrate 11 and the sliding layer 13 can be performed, for example, as follows.

[0067] First, clean the main surface 11a of the substrate 11 with alcohol or the like.

[0068] Next, the textile or woven fabric constituting the sliding layer 13, which is cut to be larger than the size of the base material 11, is placed on a workbench, and an adhesive 12 is applied thereon by a method of coating such as a bar coater or a doctor blade.

[0069] Then, the textile or woven fabric on which the adhesive 12 is applied and the base material 11 disposed thereon are set on a mold of the same type as the base material 11, so that the adhesive 12 is cured while being heated and pressurized. Finally, the excess textile or woven fabric is cut off.

[0070] (Sliding layer)

[0071] The sliding layer 13 is a textile or woven fabric containing fluorine fiber and / or glass fiber. From the viewpoint of maintaining smoothness for a long period of time, a textile is preferable. As the weaving method of the textile of fluorine fiber, plain weave, twill weave, satin weave, and the like can be exemplified.

[0072] As the fluorine fiber, polytetrafluoroethylene fiber and polyvinyl fluoride fiber are preferable.

[0073] As the material of polytetrafluoroethylene, a homopolymer of tetrafluoroethylene, or a copolymer in which the total content of tetrafluoroethylene is 90 mol% or more, preferably 95 mol% or more can be exemplified. As the monomer copolymerizable with tetrafluoroethylene, fluorinated ethylene compounds such as trifluoroethylene, trifluorochloroethylene, tetrafluoropropylene, hexafluoropropylene, and vinyl compounds such as propylene, ethylene, isobutylene, styrene, acrylonitrile can be exemplified. From the viewpoint of low frictionalization of the sliding surface, it is preferable that the content of tetrafluoroethylene units be high, and more preferable that it be a homopolymer.

[0074] The fluorine fiber can be any one of a monofilament, a multifilament, or a spun yarn. The total fineness of the fiber composed of a monofilament or a multifilament is preferably 50 to 2000 dtex, and more preferably 100 to 1000 dtex. When the total fineness of the fiber is 50 dtex or more, the strength of the fiber is enhanced and the yarn breakage resistance is increased. When the total fineness of the fiber is 2000 dtex or less, the surface unevenness when the fibers are arranged in parallel is small, and thus the sliding property is not affected, and the softness is high, and thus the shape of the base material 11 is easily followed.

[0075] The glass fiber can be a monofilament composed of one filament, or a multifilament composed of a plurality of filaments. The total fineness of the monofilament or multifilament fiber constituting the glass fiber is preferably 50 to 800 dtex, and more preferably 100 to 300 dtex. When the total fineness of the fiber constituting the textile or woven fabric is 50 dtex or more, the strength of the fiber is high, and the thread breakage during weaving is reduced, and thus the processing yield is improved. If it is 800 dtex or less, the thickness of the textile or woven fabric is thin, and the long-term durability is improved.

[0076] The surface roughness Ra of the sliding surface 13a of the sliding layer 13 is preferably 12 μm or less, more preferably 0.5 μm or more and 12.0 μm or less, and further preferably 0.5 μm or more and 10.0 μm or less.

[0077] The method for measuring the surface roughness Ra is the method described in the Examples below.

[0078] When the surface roughness Ra of the sliding surface 13a is within the above range, the sliding surface 13a can be made smooth even if the sliding surface 13a is a woven fabric or a knitted fabric, and heat can be transmitted to the fixing belt well, so that a high-quality image can be obtained.

[0079] The sliding layer 13 is preferably made by hot-pressing or cold-pressing the above woven fabric or knitted fabric. The hot-pressing can be performed using a known hot-pressing machine. The heating temperature depends on the material of the woven fabric or knitted fabric, but is preferably 150°C or more and 200°C or less. The pressure depends on the material of the woven fabric or knitted fabric and the desired thickness, but is preferably 2 MPa or more and 6 MPa or less.

[0080] The thickness of the sliding layer 13 is preferably 300 μm or more and 1000 μm or less, and more preferably 400 μm or more and 700 μm or less.

[0081] In the fixing pad 10 of the present embodiment, the sliding layer 13 is formed on the entire surface of the main surface 11a, which is the surface of the base material 11 on the opposite side from the pressure roller 23. Since the sliding layer 13 is provided on the entire surface of the main surface 11a, the fixing belt 21 can slide well without being caught by the end of the woven fabric or knitted fabric forming the sliding layer 13.

[0082] In addition, the sliding layer 13 can not be provided on the entire main surface 11a, but can be provided in a region in which the desired nip width with the pressure roller 23 can be ensured.

[0083] Before the adhesive 12 is applied, a primer can be applied to the main surface 11a of the base material 11 for bonding the sliding layer 13 to form a primer layer. Thereby, the adhesion between the base material 11 and the adhesive 12 becomes stronger.

[0084] As the primer, NO. 4 (manufactured by Shin-Etsu Chemical Co., Ltd.) or NO. 33 (manufactured by Shin-Etsu Chemical Co., Ltd.) can be exemplified.

[0085] Since the fixing pad 10 of the present embodiment uses an adhesive to bond the sliding layer 13, a smooth sliding surface 13a can be obtained, so that the fixing of the developer can be performed uniformly, and a good image can be obtained.

[0086] As Figure 2As shown, the fixing pad 10 of the present application is used for a toner fixing device 20 of an image forming apparatus.

[0087] The fixing pad 10 is configured to be opposed to the pressure roller 23 and to be pressure-bonded to each other with a predetermined nip width. The pressure roller 23 is provided with an elastic body 25 and a cover layer 26 on the outer periphery of a shaft body 24, and is rotationally driven by a driving unit (not shown). The fixing belt 21 is wound around the fixing pad 10, and is rotated along with the pressure roller 23.

[0088] The fixing pad 10 is connected to a heating device 22, and the sliding surface 13a of the fixing pad 10 is heated by the heating device 22 so that the fixing belt 21 is heated. The pressure roller is also heated by a heating unit (not shown). In a state where the fixing belt 21 and the pressure roller 23 are heated, when the recording medium 36 on which the developer 42 is transferred is conveyed and pressure-bonded between the fixing belt 21 and the pressure roller 23, the developer 42 is heated and pressurized, and thus is fixed on the recording medium 36.

[0089] [Image forming apparatus]

[0090] Next, referring to Figure 4 An embodiment of the image forming apparatus of the present application provided with a cleaning roller for an image bearing member will be described.

[0091] As Figure 4 shown, the image forming apparatus 30 is provided with a rotatable image bearing member 31 such as a photosensitive member that forms an electrostatic latent image, a charging roller 32 disposed around the image bearing member 31, an exposure unit 33, a developing unit 40, a transfer roller 34, a cleaning roller 35 for an image bearing member, and a toner fixing device 20 located on the downstream side of the conveying direction of a recording medium 36. As described above, the toner fixing device 20 is provided with a pressure roller, a fixing pad 10 disposed opposite the pressure roller, a heating device 22, and a fixing belt (endless belt) 21. The pressure roller 23 is also connected to a heating device (not shown).

[0092] The developing unit 40 is provided with a developer accommodating portion 41, a developer bearing member 44 for supplying the developer 42 to the image bearing member 31, a developer supply unit 43 for supplying the developer 42 to the developer bearing member 44, and a developer conditioning member 45 for electrifying the developer 42. The developer 42 can be a single-component developer, and can be a dry-type developer or a wet-type developer. The developer 42 can also be a non-magnetic developer or a magnetic developer.

[0093] The toner fixing device 20 fixes the developer 42 (electrostatic latent image) transferred to the recording medium 36. It has a heating device. The toner fixing device 20 is disposed in the housing 27 having an opening 28 for passing the recording medium 36, and has a fixing pad 10, a fixing belt 21, and a pressure roller 23 disposed opposite to the fixing pad 10; it is configured as a pressure heat fixing device in which the fixing belt 21, the fixing pad 10, and the pressure roller 23 are rotatably supported in abutment or pressure contact with each other.

[0094] The image forming device 30 operates as follows. First, in the image forming device 30, the image bearing member 31 is uniformly charged by the charging roller 32, and an electrostatic latent image is formed on the surface of the image bearing member 31 by the exposure unit 33. Then, the developer 42 is supplied from the developing unit 40 to the image bearing member 31 to develop the electrostatic latent image. Then, the developer image is transferred to the recording medium 36 conveyed between the image bearing member 31 and the transfer roller 34. The recording medium 36 is conveyed to the toner fixing device 20, and the developer image is fixed on the recording medium 36 as a permanent image. In this way, an image can be formed on the recording medium 36. The image bearing member 31 after the developer image is transferred is cleaned by the image bearing member cleaning roller 35 disposed on the upstream side of the charging roller 32 to remove the developer adhering or remaining on the outer peripheral surface thereof.

[0095] The image forming device 30 of the present embodiment is an electrophotographic image forming device, but in the present application, the image forming device is not limited to the electrophotographic image forming device, and for example, can be an electrostatic image forming device. Further, although the image forming device 30 is a monochrome image forming device in which only a monochrome developer 42 is housed in the developing unit 40, in the present application, the image forming device is not limited to the monochrome image forming device, and can be a four-cycle color image forming device in which the developer image carried on the image bearing member is sequentially transferred to an intermediate transfer member. As the color image forming device, for example, a tandem color image forming device in which a plurality of image bearing members each having a developing unit of a different color are arranged in series on an intermediate transfer body or a transfer conveyance belt, an image forming device on an image bearing member, and the like can be cited. The image forming device 30 is, for example, an image forming device of a copier, a facsimile, a printer, or the like.

[0096] Further, in the image forming device 30, a single-component developer is advantageously used as the developer 42, but a two-component developer including a carrier of toner and iron, nickel, or the like can also be used.

[0097] The image forming apparatus 30 according to the present application is not limited to the above-described embodiment, and various modifications can be made within a range where the object of the present application can be achieved. For example, as the image forming apparatus, various image forming apparatuses can be exemplified, and preferably, an image forming apparatus capable of forming an image at high speed is exemplified.

[0098] Embodiment

[0099] Hereinafter, the present application will be described in detail by exemplifying embodiments. In addition, the present application is not limited to the embodiments shown below.

[0100] [Embodiment 1]

[0101] A fixing pad was produced using the following materials.

[0102] Substrate: Copper plate thickness 0.4 mm

[0103] Fluorine fiber: Thickness 500 μm

[0104] Adhesive: Insulating adhesive (trade name "TSE322", manufactured by Momentive Japan Co., Ltd.)

[0105] The adhesive was applied to the copper plate, and was pressed at 150°C, 2.0 MPa for 3 minutes, and then the fluorine fiber was placed thereon and was pressed at 150°C, 10 MPa for 3 minutes.

[0106] [Embodiment 2, Embodiment 3, Comparative Example 1, and Comparative Example 2]

[0107] A fixing pad was produced in the same manner as in Embodiment 1 except that the surface roughness of the sliding surface was as shown in Table 1.

[0108] (Measurement of surface roughness Ra of the sliding surface of the fixing pad)

[0109] The measurement method of the surface roughness Ra was measurement using the following measuring instrument under the following conditions.

[0110] Measuring instrument: Surface roughness profilometer (model number: SURFCOM 1400D-3DF, manufactured by Tokyo Precision Co., Ltd.)

[0111] Parameter calculation standard: JIS '01 standard

[0112] Cutoff type: Gaussian

[0113] Measurement length: 20.0 mm

[0114] Measurement speed: 0.3 mm / sec

[0115] Three positions of L (left end), C (center), and R (right end) in the longitudinal direction were measured, and the average value was obtained. For L (left end) and R (right end), the positions at 10 mm from the inner side of both ends were measured, and for the width direction, the position at the center was measured.

[0116] [evaluation]

[0117] The toner and an OHP sheet (A4 size 297 mm x 210 mm) were overlapped in order on the sliding surface of the fixing pad, and the toner was fused under conditions of 0.5 MPa, 200°C, and 20 sec, and then cooled to ordinary temperature, and the solidified toner was transferred in a width of about 5 cm in the transverse direction of the OHP sheet to form an image. The image surface roughness and the image surface waviness WCA of the formed image were measured by the following measurement methods.

[0118] (Image surface roughness Ra)

[0119] The measurement conditions of the image surface roughness Ra were as follows.

[0120] Measuring apparatus: surface roughness profilometer (model: SURFCOM 1400D-3DF, manufactured by Tokyo Precision Co., Ltd.)

[0121] Parameter calculation standard: JIS- '01 standard

[0122] Cutoff type: Gaussian

[0123] Measurement length: 20.0 mm

[0124] Measurement speed: 0.3 mm / sec

[0125] Three positions of L (left end), C (center), and R (right end) in the transverse direction of the image surface were measured, and the average value was obtained. For L (left end) and R (right end), the positions at 20 mm from the inner side of both ends were measured, and for the width direction, the position at the center was measured.

[0126] (Image surface waviness WCA)

[0127] The measurement conditions of the image surface waviness were as follows.

[0128] Measuring apparatus: surface roughness profilometer (model: SURFCOM 1400D-3DF, manufactured by Tokyo Precision Co., Ltd.)

[0129] Parameter calculation standard: JIS- '94 standard

[0130] Measurement type: filtered center line waviness measurement

[0131] Cutoff type: Gaussian

[0132] Cut-off wavelength: 0.25-8.0 mm

[0133] Measurement length: 16.0 mm

[0134] Measurement speed: 0.3 mm / sec

[0135] Slope correction: Least square linear correction

[0136] The L (left end), C (center), and R (right end) positions of the image surface were measured in the lateral direction, and the average value was obtained. For the L (left end) and R (right end), the positions 20 mm inside from both ends were measured, and for the width direction, the center position was measured.

[0137] (Determination)

[0138] As for the surface roughness and waviness of the transferred image surface (toner unevenness), when the values were low and the toner was smoothly transferred, it was determined as A, and when the values were high and the toner was unevenly transferred, it was determined as B. The evaluation results are shown in Table 1.

[0139] Table 1

[0140]

[0141] As shown in Table 1, since the present application has a fluorine fiber, and the surface roughness Ra is 12 μm or less, it makes it possible to uniformly fix the toner, and provides a good image.

Claims

1. A fixing pad, having: a copper base material having a cross section in a transverse direction in a U shape, and a sliding layer provided on a main surface of the copper base material; wherein the sliding layer is a woven fabric or a knitted fabric containing a fluorine fiber and / or a glass fiber; a surface roughness Ra of a sliding surface of the sliding layer is 12.0 μm or less, an image surface waviness WCA of a toner image formed using the fixing pad is 1.25 μm or more and 1.98 μm or less.

2. The fixing pad according to claim 1, wherein a thickness of the sliding layer is 300 μm or more and 1000 μm or less.

3. The fixing pad according to claim 1 or 2, wherein the copper base material and the sliding layer are adhered using a one-component liquid silicone rubber adhesive.

4. The fixing pad according to claim 1 or 2, wherein the sliding layer is provided on an entire surface of the main surface of the copper base material.

5. The fixing pad according to claim 3, wherein the sliding layer is provided on an entire surface of the main surface of the copper base material. ​ ​ ​ ​ ​ ​ ​ ​ ​

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