JP2005165291A - Endless metal belt, fixing belt and heat fixing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endless metal belt superior in flexing resistance and durability, a fixing belt using the endless metal belt, and a heat fixing device with high durability and high reliability. <P>SOLUTION: Disclosed are the endless metal belt. which is formed of a nickel alloy containing 5% by weight or more of an additional metallic element and has a half-value width of an X-ray diffraction peak in a range of 0.5 to 2° for each of a (111) crystal plane and a (200) crystal plane, and the fixing belt and heat fixing device that use the endless metal belt. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an endless metal belt, a fixing belt, and a heat fixing device used in an image forming apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus.

  In image forming processes such as electrophotographic process, electrostatic recording process and magnetic recording process, transfer method or recording material (transfer material sheet, electrofax sheet, electrostatic recording paper, OHP sheet, printing paper, format paper, etc.) 2. Description of the Related Art A belt heating type heat fixing device is used which forms an unfixed image (toner image) formed and supported by a direct method as a permanently fixed image on a recording material surface.

  On the other hand, as a heat fixing device of the belt heating type, a heater heating type that heats a resin belt or a metal belt having a small heat capacity using a ceramic heater as a heat source has been widely proposed and implemented. That is, in a heater heating type belt heating type heat fixing apparatus, generally, a nip portion is formed by sandwiching a heat resistant belt (fixing belt) between a ceramic heater as a heating body and a pressure roller as a pressure member. A recording material on which an unfixed toner image is carried is introduced between the fixing belt and the pressure roller, and is sandwiched between the fixing belt and the pressure roller and conveyed together with the fixing belt. Heat of the heater is applied to the recording material via the belt, and the unfixed toner image is heated and fixed on the surface of the recording material by this heat and the applied pressure of the nip portion.

  This heater heating type belt heating type heat fixing device can constitute an on-demand type device by using a low heat capacity member as a fixing belt. That is, only when the image forming apparatus performs image formation, the ceramic heater of the heat source is energized and heated to a predetermined fixing temperature, and the waiting time from power-on of the image forming apparatus to the image forming executable state is short (quick start ) And power consumption during standby can be greatly reduced (power can be saved).

  It has been proposed to use a metal-based fixing belt as a fixing belt in such a heater-heating type belt-heating type heat-fixing apparatus.

  A metal such as seamless SUS or nickel is generally used for a fixing belt made of metal, and a seamless belt made of a SUS material is known by a plastic working method such as spinning (for example, Patent Document 1). reference.). A seamless belt made of a nickel material is generally manufactured by an electroforming method (sometimes referred to as an electroforming method) using a nickel sulfamate bath or a nickel sulfate bath (see, for example, Patent Documents 2 and 3).

  In general, SUS belts made by plastic working methods (rolling, drawing, spinning, etc.) are required to be small, high speed, and highly durable fixing devices. This is a situation where it is not possible to cope with the change (thickness 15 μm or less). And since the stress distribution of MD direction and TD direction differs, there exists a possibility that the crystal axis of a SUS material may align in one direction, and may generate | occur | produce a crack.

  On the other hand, electroformed nickel belts are mainly focused on heat resistance and tend to sacrifice strength and wear resistance. For this reason, a fixing belt manufactured using such an electroformed nickel belt is usually provided with a sliding layer made of polyimide or the like on the sliding surface. However, since the thermal conductivity of so-called resin-based materials including polyimide is about 300 times smaller than that of the nickel material, the start-up time becomes long, and the merit of the nickel material with good thermal conductivity is hidden.

  In single metal electroforming, it is difficult to have performance that satisfies all the requirements such as yield strength, abrasion resistance, and bending resistance. For this reason, a method for manufacturing an electroformed belt having more excellent characteristics in combination with various metal elements has been proposed. For example, an electroformed nickel belt containing at least one metal element belonging to Groups 2, 3, 4, and 5 of the periodic table in a mass fraction of 10 to 10,000 ppm (1 mass%) is disclosed. The metal elements of Groups 2 to 5 of the periodic table have the function of adjusting the growth of the nickel-plated crystal, orderly growing the crystal, and promoting the orientation. These elements are the heat of the nickel-plated crystal. It is presumed that an electroformed nickel belt excellent in heat resistance was obtained because of its effect of suppressing coarsening due to heat aging, and the hardness was not easily lowered by heat aging (see, for example, Patent Document 4). ).

  Further, when the mass fraction of the Group 2 to Group 5 metal elements in the periodic table exceeds 10,000 ppm (1% by mass), these metal elements precipitate at the grain boundaries, and the electroformed nickel belt becomes It is disclosed that it tends to be brittle (see, for example, Patent Document 4).

  Actually, many binary and ternary alloy platings are widely used industrially as mechanical parts and electronic parts. The mechanical and electrical properties of alloy plating are closely related to its composition. Further, the existence state of the alloy element (compound, crystalline, solid solution, etc.) affects the characteristics (hardness, flexibility, electrodeposition stress, etc.) of the alloy plating.

  The fixing belt used in the heat fixing apparatus must have durability for a long time. Furthermore, demands for energy saving and space saving have become stricter, and heat fixing devices used in image forming apparatuses are becoming smaller and faster, fixing belt diameters are reduced, and metal belts are being made thinner. The belt is required to have sufficient wear resistance and excellent properties such as flex resistance, flexibility and durability.

JP 2001-225134 A JP 09-034286 A JP 2001-215820 A Japanese Patent Laid-Open No. 2002-241984

  In addition, even in an electromagnetic induction heating type belt fixing heating fixing device that directly fixes a metal belt by electromagnetic induction heating, the size and speed of the heating fixing device, the diameter of the fixing belt can be reduced, and the metal belt can be made thinner. Along with this, metal belts are required to have sufficient wear resistance and excellent properties such as flex resistance, flexibility and durability.

An object of the present invention is to provide an endless metal belt that is more excellent in bending resistance, flexibility, and durability than an endless metal belt made of a conventional nickel alloy.
Another object of the present invention is to provide a fixing belt using the endless metal belt, and a heat fixing device using the fixing belt as a fixing member.

  In order to solve the above problems, the present invention is an endless metal belt made of a nickel alloy, the nickel alloy being a nickel alloy containing 5% by mass or more of another metal element, a (111) crystal plane and (200 ) Provide an endless metal belt characterized in that the half width of the X-ray diffraction peak of the crystal plane (the peak width at half the height of the X-ray diffraction peak) is 0.5 ° to 2 °. To do.

The present invention also provides a fixing belt, wherein the metal belt layer of the fixing belt is the endless metal belt of the present invention.
The present invention also relates to a heating and fixing apparatus in which a recording material holding an unfixed image is nipped and conveyed by a nip formed by a pair of fixing members each having a belt shape, and is heated and fixed. The fixing member having the above is the fixing belt of the present invention.

  In the present invention, a nickel alloy of an endless metal belt made of a nickel alloy containing 5% by mass or more of another metal element has both half-value widths of X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane being 0. A high-quality endless metal belt having excellent bending resistance, good durability, and fixability, a fixing belt using the same, and the fixing belt A heat fixing device can be provided.

  The embodiment of the present invention will be further described.

<Fixing belt>
FIG. 1 is a schematic diagram for explaining a layer structure of a fixing belt 10 according to an embodiment of the present invention. The fixing belt 10 of the present invention is coated on the elastic layer 2 via the metal belt layer 1 constituted by the endless metal belt of the present invention described below, the elastic layer 2 laminated on the outer peripheral surface thereof, and the adhesive layer 3. The release layer 4 is provided. In the fixing belt 10, the metal belt layer 1 side is the inner peripheral surface side (belt guide surface side) of the fixing belt 10, and the release layer 4 side is the outer peripheral surface side (pressure roller surface side) of the fixing belt 10. A primer layer (not shown) may be provided between the metal belt layer 1 and the elastic layer 2 in order to improve adhesion. The primer layer (not shown) may be a known primer such as silicone, epoxy, or polyamideimide, and the layer thickness is usually about 1 to 10 μm. Since the metal belt layer 1 constituted by the endless metal belt according to the present invention has sufficient wear resistance, the inner surface side (belt guide surface side) of the metal belt layer 1 can be used as a direct sliding surface. However, a sliding layer may be provided. If desired, a sliding layer (not shown) made of a resin such as polyimide may be provided on the inner surface side of the metal belt layer 1.

  FIG. 2 is a schematic diagram for explaining a layer structure of the fixing belt 20 according to another embodiment of the present invention. An elastic layer is not formed on the outer surface side of the metal belt layer 1, and a release layer 4 is formed on the metal belt layer 1 via an adhesive layer 3. In particular, in the case of a fixing belt of a heating and fixing device for monochrome images in which the toner amount on the recording material is small and the unevenness of the toner layer is relatively small, and in the case of a fixing belt for heating only, such an elastic layer is provided. It can be of a form that is not.

  Even when the metal belt layer 1 of the fixing belt 10 or 20 is used in a heater heating type belt heating type heating fixing device using a ceramic heater or the like (FIG. 3), an electromagnetic induction heating type belt heating type heating fixing device. Even when it is used for (FIG. 4), sufficient physical and mechanical functions can be achieved.

<Endless metal belt>
The endless metal belt of the present invention is an endless metal belt made of a nickel alloy. This nickel alloy is a nickel alloy containing 5% by mass or more of other metal elements, and has a (111) crystal face and a (200) crystal. Both of the half widths of the X-ray diffraction peaks of the surface are 0.5 ° to 2 °. The nickel alloy preferably contains at least one nonmetallic element selected from the group consisting of sulfur and carbon.

  As the endless metal belt of the present invention, an electroforming method, for example, a cylindrical mother die made of stainless steel or the like is immersed in an electrolytic bath, and the mother die is used as a cathode, and the outer peripheral surface or inner periphery of the mother die is used. It is preferable that a film made of a nickel alloy having the above composition is formed on the surface by an electroforming process, and the film is peeled off from the matrix.

  As the electrolytic bath in this case, for example, a known nickel electrolytic bath such as nickel sulfamate or nickel sulfate to which other necessary metal elements are added can be used.

  Examples of other metal elements contained in the nickel alloy include Co, Mn, Sn, W, Cu, and Zn. These other metal elements are preferably contained in an amount of 5 to 50% by mass, more preferably 10 to 40% by mass, based on the total mass of the nickel alloy. When the content of these other metal elements is 5% by mass or more, the solid solution effect of the nickel alloy constituting the endless metal belt is expressed, and the X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane are expressed. It becomes possible to obtain a nickel alloy in which the half widths are both 0.5 ° to 2.0 °. Flexibility and durability are improved by this solid solution effect. It is preferable that the content of these other metal elements be 50% by mass or less because flexibility suitable for the belt can be secured.

  In order to introduce these other metal elements into the endless metal belt of the present invention, for example, a compound such as Co, Mn, Sn, Cu, Zn may be added to the electrolytic bath. Although depending on the compound used, these compounds are usually added so that the concentration of these other metal elements is 1 to 300 g / l when the nickel concentration is 450 g / l.

  In the present invention, it is preferable that the nickel alloy further includes at least one nonmetallic element selected from the group consisting of sulfur and carbon. These nonmetallic elements are preferably contained in an amount of 0.002 to 0.05 mass%, more preferably 0.005 to 0.03% by mass, based on the total mass of the nickel alloy. When the content of these nonmetallic elements is 0.002% by mass or more, the surface smoothness is improved. When the content of these nonmetallic elements is 0.05% by mass or less, heat resistance can be secured, which is preferable.

  In order to introduce these nonmetallic elements into the nickel alloy constituting the endless metal belt of the present invention, for example, a compound such as saccharin sodium or butynediol may be added to the electrolytic bath. Although depending on the compounds used, these compounds are usually added so that the concentration of these nonmetallic elements is 0.01 to 0.5 g / l when the nickel concentration is 450 g / l.

You may add suitably additives, such as a pH adjuster, a pit inhibitor, and a brightener, to an electrolytic bath.
Examples of the pH adjuster that can be used in the present invention include nickel chloride, nickel sulfate, and sulfuric acid.

  Examples of the pit preventing agent include sulfate salts of lauryl alcohol such as sodium lauryl sulfate, sodium laurate, sodium naphthalene disulfonate, and the like.

  As a brightener, add a brightener called stress reducer or primary brightener such as saccharin, sodium saccharin, sodium benzenesulfonate or sodium naphthalenesulfonate, or a secondary brightener such as butynediol, coumarin, or diethyltriamine. Can do.

  Specific examples of the electrolytic bath that can be used for producing the endless metal belt of the present invention include, for example, when the other metal element is cobalt, nickel sulfamate 400 to 650 g / l, nickel chloride 0 to 60 g / l, A nickel electrolytic bath composed of 80 g / l of cobalt sulfamate and 20 to 55 g / l of boric acid can be mentioned.

  An endless metal belt according to the present invention has an (111) crystal plane and (200) in an X-ray diffraction pattern obtained by plotting the X-ray diffraction intensity of a nickel alloy of the endless metal belt against a diffraction angle 2θ. It is an endless metal belt made of a nickel alloy in which the half widths of the X-ray diffraction peaks of the crystal plane are both 0.5 ° to 2 °. An endless metal belt made of a nickel alloy in which the half widths of the X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane are both 0.5 ° to 2 ° has high strength and high hardness, It has excellent bending resistance due to the solid solution effect, and is used in the manufacture of a small-diameter fixing belt that requires bending resistance, and can ensure higher durability.

  The above-mentioned solid solution effect of the nickel alloy constituting the endless metal belt of the present invention includes the effect of the interstitial solid solution, but mainly metal elements other than nickel replace the crystal lattice atoms of nickel metal, This is considered to be a substitutional solid solution effect that is manifested by producing a solid solution or a supersaturated solid solution.

  An intrusion-type solid solution is formed by entering a solute atom having a small atomic diameter such as carbon, nitrogen, or hydrogen atom into a gap between crystal lattices formed by parent phase atoms having a remarkably large atomic diameter.

  The substitutional solid solution is formed by replacing the solute atoms with a part of the lattice points of the crystal lattice formed by the parent phase atoms, and the atomic diameter is almost the same as the atomic diameter of the parent phase atoms and the difference is small.

  In general, the internal stress of the nickel alloy in the present invention includes internal stress caused by distortion such as elastic contraction or extension of the crystal lattice of the parent phase metal due to macroscopic stress such as external force acting on the nickel alloy, and solute in a minute region. It is known that there are two types of microscopic internal stress caused by penetration of crystal lattice gaps, substitution of atoms at crystal lattice points, and the like. The state of distortion of the crystal lattice due to these internal stresses can be known from the X-ray diffraction pattern.

  For example, FIG. 5 schematically shows X-ray diffraction peaks of a nickel alloy to which no internal stress is applied and a nickel alloy under the above-described internal stress. 5A is an X-ray diffraction peak of a crystal plane of a nickel alloy in the absence of internal stress, the X-ray diffraction peak of the crystal plane of the nickel alloy under the action of internal stress caused by macroscopic stress. As shown in FIG. 5B, the peak position is shifted to the left or right from the peak position shown in FIG. This indicates that the interplanar spacing of the crystal planes is uniformly compressed or expanded over a macroscopic range due to macroscopic stress. Further, the X-ray diffraction peak of the crystal plane of the nickel alloy under the microscopic internal stress does not change the peak position of the X-ray diffraction peak as shown in FIG. This indicates that the crystal lattice of the nickel alloy is contracted in the microscopic region while being expanded by the microscopic internal stress. For this reason, when the microscopic internal stress increases, the full width at half maximum of the X-ray diffraction peak increases.

  An endless metal belt made of a nickel alloy under an appropriate range of microscopic stress provides improved hardness, yield strength, and bending resistance. Therefore, when the half width of the X-ray diffraction peak is in a predetermined range, the characteristics of the endless metal belt, particularly the yield strength and the bending resistance are improved.

  The characteristics of the nickel alloy constituting the endless metal belt manufactured by the electroforming method, particularly the characteristics such as the yield strength and the bending resistance, are affected by the electroforming conditions. In the electroforming process of the present invention, by controlling the electrolytic bath composition and controlling the cathode current density, electrolytic bath pH value, concentration of brightener added, electrolytic bath temperature, etc., the desired alloy composition and X-ray diffraction peak are controlled. An endless metal belt made of a nickel alloy having a half width of can be obtained.

In the present invention, although depending on the electrolytic bath, for example, the cathode current density in the electroforming process is usually controlled to ¹ to 30 A / dm ² , preferably 5 to 15 A / dm ² , and the pH value of the electrolytic bath is, for example, In general, it is controlled to 2.5 to 9, preferably 3.5 to 4.5, and the electrolytic bath temperature is usually 30 to 65 ° C., preferably 45 to 55 ° C. % Of the X-ray diffraction peaks of the (111) crystal face and the (200) crystal face of the nickel alloy constituting the endless metal belt are both 0.5 ° to It is possible to obtain an endless metal belt having a high hardness and a high strength due to a solid solution effect and having excellent bending resistance. As a result, high durability can be reliably ensured even in a small-diameter fixing belt that requires strict bending resistance and a heat fixing apparatus using the same.

  In order to reduce the heat capacity and improve the quick start property, the thickness of the endless metal belt is usually preferably 10 μm to 100 μm, more preferably 15 μm to 60 μm. When the thickness of the endless metal belt is 10 μm or more, no wrinkle is generated during the production of the endless metal belt or when the fixing belt is manufactured using the endless metal belt. A product having excellent mobility and bending resistance can be produced. According to the present invention, a thin endless metal belt having a thickness of 10 μm or more and 25 μm or less can be easily manufactured, and a fixing belt having a thin metal belt layer constituted by such a thin endless metal belt is provided. It can be manufactured easily.

<Elastic layer>
The fixing belt of the present invention may be provided with the elastic layer 2 or not. When the elastic layer 2 is provided, the elastic layer 2 covers the image to be heated in the nip portion to ensure heat transfer, and can compensate for the restoring force of the metal belt layer and reduce fatigue of the fixing belt due to rotation and bending. . Further, when the elastic layer 2 is provided, the followability of the surface of the release layer of the fixing belt to the surface of the unfixed toner image is increased, and heat can be efficiently transmitted. The fixing belt provided with the elastic layer 2 is particularly suitable for heat fixing of a color image having a large amount of unfixed toner.

  The material of the elastic layer 2 is not particularly limited, and a material having good heat resistance and good thermal conductivity may be selected. The elastic layer 2 is preferably an elastic layer formed from silicone rubber, fluorine rubber, fluorosilicone rubber or the like, and more preferably an elastic layer formed from silicone rubber.

  The silicone rubber forming the elastic layer 2 includes polydimethylsiloxane, polymethyltrifluoropropylsiloxane, polymethylvinylsiloxane, polytrifluoropropylvinylsiloxane, polymethylphenylsiloxane, polyphenylvinylsiloxane, and these polysiloxanes. Examples thereof include copolymers containing monomer units.

  If necessary, the elastic layer 2 has a reinforcing filler such as dry silica and wet silica, calcium carbonate, quartz powder, zirconium silicate, clay (aluminum silicate), talc (hydrous magnesium silicate), alumina (aluminum oxide), Bengala (iron oxide) or the like may be included.

  The thickness of the elastic layer 2 is preferably 10 μm to 1000 μm and more preferably 50 μm to 500 μm from the viewpoint that a fixed image with good quality can be obtained. When the thickness of the elastic layer 2 is 1000 μm or less, the thermal resistance of the elastic layer is preferably reduced.

  When a color image is printed, a solid image may be formed over a large area on the recording material P, particularly in a photographic image. In such a case, if the heating surface (release layer 4) cannot follow the unevenness of the recording material or the unevenness of the surface of the unfixed toner image, heating unevenness occurs, and the image has a glossy portion with a large amount of heat transfer and a small amount of heat transfer. Unevenness occurs. Usually, the glossiness is high in a portion with a large amount of heat transfer, and the glossiness is low in a portion with a small amount of heat transfer. If the elastic layer 2 is too thin, unevenness in the image gloss may occur because it cannot follow the unevenness of the surface of the recording material or the unfixed toner image. On the other hand, if the elastic layer 2 is too thick, the thermal resistance of the elastic layer 2 may increase and it may be difficult to realize a quick start.

  The hardness of the elastic layer 2 (JIS-K-6253 (ISO-7619) established in 1993 in conformity with international standards is sufficient to suppress the occurrence of uneven image gloss and to obtain a good fixed image quality. 1 ° to 60 °, and 5 ° to 45 ° are more preferable.

The thermal conductivity λ of the elastic layer 2 is preferably 2.5 × 10 ⁻³ [W / cm · ° C.] to 5.0 × 10 ⁻² [W / cm · ° C.], more preferably 5.0 × 10. ^-3 [W / cm · ° C] to 3.0 × 10 ^-2 [W / cm · ° C]. When the thermal conductivity λ is too small, the thermal resistance of the fixing belt becomes too large, and the temperature rise in the surface layer (release layer 4) of the fixing belt may be delayed. When the thermal conductivity λ is too large, the hardness of the elastic layer 2 may increase or the compression set may increase.

  The elastic layer 2 is a known method, for example, a method in which a material such as liquid silicone rubber is coated on the outer peripheral surface of the endless metal belt with a uniform thickness by means such as a blade coating method, and is heated and cured. It may be formed by a method of injecting a material such as a mold into a mold and vulcanizing and curing; a method of vulcanizing and curing after extrusion molding; a method of vulcanizing and curing after injection molding.

<Release layer>
The material for forming the release layer 4 is not particularly limited, and a material having good release properties and heat resistance may be selected. As a material for forming the release layer 4, fluorine such as PFA (tetrafluoroethylene / perfluoroalkyl ether copolymer), PTFE (polytetrafluoroethylene), FEP (tetrafluoroethylene / hexafluoropropylene copolymer), etc. Resins, silicone resins, fluorosilicone rubbers, fluororubbers, silicone rubbers and the like are preferable, and PFA is more preferable. If necessary, the release layer 4 can contain a conductive agent such as carbon or tin oxide. The content of the conductive agent is not particularly limited, but in general, it is preferable to contain the conductive agent in an amount of 10% by mass or less with respect to the mass of the release layer 4.

  In general, the thickness of the release layer 4 is preferably 1 μm to 100 μm. If the release layer 4 is too thin, a portion having poor release properties may be formed due to uneven coating of the coating film, or durability may be insufficient. Further, if the release layer is too thick, the thermal conductivity may be insufficient. In particular, in the case of a resin-based release layer, heat transferability and flexibility are reduced, and the heat transfer function and the fatigue relieving function of the elastic layer 2 due to rotation and bending may not be exhibited. is there.

  In the present invention, the release layer can be formed by a known method. For example, when a fluororesin-based release layer is formed on the elastic layer, a coating liquid in which a fluororesin powder is dispersed can be coated on the elastic layer, dried, and fired. When a fluororesin-based release layer is formed on a metal belt, a coating liquid in which fluororesin powder is dispersed directly on the adhesive layer of the endless metal belt on which an adhesive layer has been formed in advance or directly on the endless metal belt. It can be formed by coating, drying and firing. Moreover, it can form by the method of coat | covering and adhere | attaching the fluororesin previously tubed. When forming a rubber release layer, it must be formed by injecting a liquid material into a mold and vulcanizing and curing; vulcanizing and curing after extrusion molding; and vulcanizing and curing after injection molding. Can do.

  In addition, a tube with a primer treatment on the inner surface in advance, an endless metal belt of the present invention with a primer treatment on the surface in advance is mounted in a cylindrical matrix, and in the gap between the tube and the endless metal belt, for example, Liquid silicone rubber can be injected, heated to cure the silicone rubber, and bonded to form the elastic layer and the release layer simultaneously.

  When the sliding belt is provided on the fixing belt of the present invention, the material of the sliding layer is not particularly limited, and a material having high heat resistance, high strength, and smooth surface may be selected. It is preferable to configure.

  In addition, a sliding agent can be contained in the sliding layer as needed. As the sliding agent, fluorine resin powder, graphite, molybdenum disulfide, or the like can be used.

  The thickness of the sliding layer is usually preferably 5 μm to 100 μm, and more preferably 10 μm to 60 μm. If the sliding layer is too thick, the heat capacity of the fixing belt increases and the rise time may be longer.

  The sliding layer may be formed by a known method, for example, coating a liquid material on the inner surface of the metal belt layer, drying, curing, etc., or forming a tube in advance into the metal belt layer. You may stick and form.

Next, an embodiment of the heat fixing device of the present invention will be described.
<Heat fixing device>
The heat fixing device of the present invention is a heat fixing device that heats and fixes a recording material on which an unfixed toner image is held by a nip portion formed by a pair of fixing members, at least one of which has a belt shape. The fixing member of the present invention is provided as the fixing member having the belt shape. Specifically, for example, a heater heating type belt heating type heating and fixing device described below, an electromagnetic induction heating type belt heating type heating and fixing device, and the like can be given.

  FIG. 3 is a schematic view showing a cross section of the heat fixing apparatus according to the embodiment of the present invention. The heat-fixing device 200 is a heater-heating type belt-heating-type heat-fixing device using a ceramic heater as a heating body. The heat fixing device 200 includes a fixing belt 210 as a fixing member having a belt shape, and the fixing belt 210 is the above-described fixing belt of the present invention. The fixing belt 210 is preferably a small-diameter fixing belt for a belt-heating type heating fixing device. Specifically, those having a diameter of 30 mm or less are preferable.

  The belt guide 216 is a heat-resistant and heat-insulating belt guide. The ceramic heater 212 as a heating element is fixedly supported by being fitted into a groove formed along the longitudinal direction of the guide at the substantially central portion of the lower surface of the belt guide 216. The endless fixing belt 210 of the present invention is loosely fitted around the belt guide 216 and is held in a substantially cylindrical shape.

  The other fixing member of the pair of fixing members is a pressure member 230, and in the present embodiment, the pressure member 230 is a pressure roller having an elastic layer. The pressure member 230 is formed by providing an elastic layer 230b such as silicone rubber on the outer peripheral portion of the core metal 230a. Both ends of the cored bar 230a are rotatably supported and disposed between a front side (not shown) of the heat fixing device and a chassis side plate on the back side. In order to improve the surface property, the pressure roller having an elastic layer is further provided with PTFE (polytetrafluoroethylene), PFA (tetrafluoroethylene / perfluoroalkyl ether copolymer), FEP (tetrafluoroethylene) on the outer periphery of the elastic layer. A fluororesin layer such as a fluoroethylene / hexafluoropropylene copolymer) may be provided.

  The pressurizing rigid stay 222 is inserted inside the belt guide 216. A pressure spring (not shown) is contracted between both ends of the pressure rigid stay 222 and a spring receiving member (not shown) on the apparatus chassis side, and a pressing force is applied to the pressure rigid stay 222. Yes. As a result, the lower surface of the sliding plate 240 disposed on the lower surface of the ceramic heater 212 and the upper surface of the pressure roller 230 are pressed against each other with the fixing belt 210 interposed therebetween to form a nip portion N having a predetermined width.

  As a material used for manufacturing the belt guide 216, a resin having excellent heat resistance such as a heat-resistant phenol resin, an LCP (liquid crystal polyester) resin, a PPS (polyphenylene sulfide) resin, and a PEEK (polyether ether ketone) resin is preferably used. .

  The pressure roller 230 is rotationally driven counterclockwise as indicated by an arrow by a driving means (not shown). A rotational force acts on the fixing belt 210 due to friction between the pressure roller 230 and the outer surface of the fixing belt 210 due to the rotational driving of the pressure roller 230, and the inner surface of the fixing belt 210 is the nip portion N of the ceramic heater 212. While being in close contact with the lower surface and sliding, as indicated by the arrow, the belt guide 216 is rotated in the clockwise direction at a peripheral speed substantially corresponding to the rotational peripheral speed of the pressure roller 230 (pressure roller). Drive system).

  Based on the print start signal, rotation of the pressure roller 230 is started, and heat-up of the ceramic heater 212 is started. When the rotation peripheral speed of the fixing belt 210 is stabilized by the rotation of the pressure roller 230 and the temperature of the ceramic heater 212 rises to a predetermined temperature, the heated belt is heated between the fixing belt 210 and the pressure roller 230 in the nip portion N. A recording material P carrying a toner image t as a material is introduced with the toner image carrying surface side set to the fixing belt 210 side. The recording material P is in close contact with the lower surface of the ceramic heater 212 via the fixing belt 210 at the nip portion N, and moves and passes through the nip portion N together with the fixing belt 210. In the moving and passing process, the heat of the ceramic heater 212 is applied to the recording material P via the fixing belt 210, and the toner image t is heated and fixed on the surface of the recording material P. The recording material P that has passed through the nip N is transported separately from the outer surface of the fixing belt 210.

  The ceramic heater 212 as a heating body is a horizontally long linear heating body having a low heat capacity and having a longitudinal direction in a direction perpendicular to the moving direction of the fixing belt 210 and the recording material P. The ceramic heater 212 includes a heater substrate made of aluminum nitride and the like, and a heat generation layer 212a provided on the surface of the heater substrate along the longitudinal direction thereof, for example, an electric resistance material such as Ag / Pd (silver / palladium). A heat generating layer 212a provided by coating by screen printing or the like with a thickness of about 10 μm and a width of 1 to 5 mm, and a protective layer 212b such as glass or fluororesin provided thereon are used as a basic configuration. The ceramic heater to be used is not limited to this.

  And by supplying with electricity between the both ends of the heat_generation | fever layer 212a of the ceramic heater 212, the heat_generation | fever layer 212a heat | fever-generates and the heater 212 heats up rapidly. The heater temperature is detected by a temperature sensor (not shown), and energization to the heat generating layer 212a is controlled by a control circuit (not shown) so that the heater temperature is maintained at a predetermined temperature, and the ceramic heater 212 is temperature-controlled. The

  The ceramic heater 212 is fixedly supported by fitting the protective layer 212b upward in a groove formed along the longitudinal direction of the guide at the substantially central portion of the lower surface of the belt guide 216. In the nip portion N in contact with the fixing belt 210, the surface of the sliding plate 240 of the ceramic heater 212 and the inner surface of the fixing belt 210 slide in contact with each other. The width of the nip portion is changed in accordance with the process speed in order to ensure the residence time of the recording material P in the nip portion. For a process speed of 100 mm / sec or higher, the nip width is preferably set to 5 mm or higher.

  FIG. 4 is a schematic diagram showing a cross section of a heat fixing apparatus according to another embodiment of the present invention. The heat fixing device 300 is an electromagnetic induction heating type belt heating type heat fixing device, and the fixing belt is the above-described fixing belt of the present invention.

  In the heat fixing apparatus 300, the magnetic field generating means includes magnetic cores 317a, 317b and 317c and an excitation coil 318.

  The magnetic cores 317a to 317c are high-permeability members, and materials used for transformer cores such as ferrite and permalloy are preferable. In particular, it is preferable to use ferrite with low loss even at 100 kHz or higher.

  The exciting coil 318 is formed by bundling a plurality of thin copper wires each having an insulation coating (bundle wire) one by one as a conducting wire (electric wire) constituting the coil (wire ring), and winding this multiple times. Has been. In this embodiment, the exciting coil 318 is formed by winding 11 turns.

  As the insulating coating, it is preferable to use a coating having heat resistance in consideration of heat conduction due to heat generation of the fixing belt 310. For example, it is preferable to use a material coated with a polyimide resin. Here, the density may be improved by applying pressure from the outside of the exciting coil 318.

  An insulating member 319 is disposed between the magnetic field generating means and the pressurizing rigid stay 322. As a material of the insulating member 319, a material excellent in insulation and heat resistance is preferable. For example, phenol resin, fluorine resin, polyimide resin, polyamide resin, polyamideimide resin, PEEK (polyether ether ketone) resin, PES (polyether sulfone) resin, PPS (polyphenylene sulfide) resin, PFA (tetrafluoroethylene / perfluoro) Preferred examples include alkyl ether copolymer) resin, PTFE (polytetrafluoroethylene) resin, FEP (tetrafluoroethylene / hexafluoropropylene copolymer) resin, and LCP (liquid crystal polyester) resin.

  The excitation coil 318 has an excitation circuit (not shown) connected to a power feeding unit (not shown). The excitation circuit (not shown) is preferably one that can generate a high frequency of 20 kHz to 500 kHz by a switching power supply. The exciting coil 318 generates an alternating magnetic flux by an alternating current (high frequency current) supplied from an exciting circuit (not shown).

  The alternating magnetic flux guided to the magnetic cores 317a to 317c generates an eddy current in the metal belt layer (electromagnetic induction heat generating layer) 1 (FIGS. 1 and 2) of the fixing belt 310. This eddy current generates Joule heat (eddy current loss) in the metal belt layer 1 (electromagnetic induction heating layer) due to the specific resistance of the metal belt layer (electromagnetic induction heating layer) 1. The calorific value Q here is determined by the density of the magnetic flux passing through the metal belt layer (electromagnetic induction heat generating layer) 1. The temperature of the nip portion N is controlled so as to be maintained at a predetermined value by controlling the current supply to the exciting coil 318 by a temperature control system including a temperature detection unit (not shown). In the embodiment shown in FIG. 4, the temperature sensor 326 is a thermistor or the like that detects the temperature of the fixing belt 310, and controls the temperature of the nip portion N based on the temperature information of the fixing belt 310 measured by the temperature sensor 326. It is supposed to be.

  The pressure roller 330 as a pressure member is a heat-resistant elastic material such as silicone rubber, fluororubber, or fluororesin that is formed and coated in a roller shape concentrically and integrally on the outer periphery of the core metal 330a. And an elastic layer 330b made of The pressure roller 330 is disposed such that both ends of the core metal 330a are rotatably supported by bearings between chassis side plates (not shown) of the apparatus.

  A pressing force is applied to the pressure rigid stay 322 by contracting pressure springs (not illustrated) between both ends of the pressure rigid stay 322 and a spring receiving member (not illustrated) on the apparatus chassis side. ing. As a result, the lower surface of the sliding plate 340 disposed on the lower surface of the belt guide member 316 and the upper surface of the pressure roller 330 are pressed against each other with the fixing belt 310 interposed therebetween, so that a nip portion N having a predetermined width is formed. The belt guide member 316 is made of a heat-resistant phenol resin, an LCP (liquid crystal polyester) resin, a PPS (polyphenylene sulfide) resin, a PEEK (polyether ether ketone) resin, or the like that is excellent in heat resistance. It is preferable.

  The pressure roller 330 is driven to rotate counterclockwise by the driving means M as indicated by an arrow. A rotational force acts on the fixing belt 310 due to friction between the pressure roller 330 and the fixing belt 310 by the rotation driving of the pressure roller 330, and the inner surface of the fixing belt 310 is the lower surface of the sliding plate 340 at the nip portion N. As shown by the arrow, the belt guide member 316 rotates around the outer periphery of the belt guide member 316 in the clockwise direction at a peripheral speed substantially corresponding to the rotational speed of the pressure roller 330.

  In this way, the pressure roller 330 is rotationally driven, and the fixing belt 310 is rotated accordingly, and electromagnetic induction heat generation of the fixing belt 310 is generated as described above by feeding power from an excitation circuit (not shown) to the excitation coil (not shown). The recording material P on which the unfixed toner image t conveyed from the image forming unit is formed with the fixing belt 310 of the nip N in the state where the nip N rises to a predetermined temperature and is adjusted in temperature. Between the pressure roller 330 and the pressure roller 330, the image surface is introduced upward, that is, facing the fixing belt surface. Then, the image surface closely contacts the outer surface of the fixing belt 310 at the nip portion N, and the nip portion N is nipped and conveyed together with the fixing belt 310. In this process, the unfixed toner image t is heated and fixed on the surface of the recording material P by being heated by electromagnetic induction heat generated by the fixing belt 310. When the recording material P passes through the fixing nip portion N, it is separated from the outer surface of the fixing belt 310 and discharged and conveyed.

  The heat-fixed toner image on the recording material passes through the nip portion N and is then cooled to become a permanently fixed image. In this embodiment, an oil application mechanism for preventing offset is not provided in the fixing device, but an oil application mechanism may be provided when a toner containing a low softening substance is used. Even when a toner not containing a low softening substance is used, the recording material P may be separated and discharged and conveyed by applying oil or cooling.

  Further, the pressure member 330 is not limited to a fixing member having a roller shape such as a pressure roller, but may be a fixing member of another form such as a rotating film type. Further, in order to supply heat energy from the pressure roller 330 side to the recording material P, heat generation means such as an electromagnetic induction heating method is also provided on the pressure roller 330 side to heat the temperature to a predetermined temperature. An apparatus configuration can also be adopted.

Hereinafter, the present invention will be described in more detail with reference to examples.
As described in Examples and Comparative Examples, an endless metal belt having an inner diameter of 18 mm and a thickness of 20 μm or 25 μm was prepared, and thermal conductivity of 5.0 × 10 ⁻³ W / cm · ° C. and hardness of 10 ° (JIS) A silicone rubber layer of -A) was formed to a thickness of 300 μm, and a PFA tube having a thickness of 25 μm was covered with an adhesive to prepare a fixing belt having a length of 250 mm.

  Further, a method for analyzing the composition of the nickel alloy of the obtained endless metal belt, a method for measuring the half-value width of the X-ray diffraction peak, and an idling durability test method using a heat fixing device provided with the obtained fixing belt, and this The actual endurance paper passing test method using the image forming apparatus equipped with the heat fixing device is as follows.

(Analysis method of the composition of the nickel alloy constituting the endless metal belt)
The contents of nickel and other metal elements in the endless metal belts of Examples and Comparative Examples were quantitatively analyzed using a RIX3000 type fluorescent X-ray analyzer (trade name) manufactured by Rigaku Corporation. Other metal elements (such as manganese) contained in a small amount in the nickel alloy were quantitatively analyzed using an inductively coupled plasma emission analyzer (ICP Vista-PRO; trade name) manufactured by Seiko Co., Ltd.
Further, the content of nonmetallic elements such as sulfur and carbon contained in the nickel alloy was measured by a combustion infrared absorption method using a CS-444 type measuring device (trade name) manufactured by LECO, USA. It was confirmed that the analysis accuracy of sulfur and carbon by this measuring apparatus was 1 ppm (0.0001 mass%).

(Measuring method of half width of X-ray diffraction peak of nickel alloy of endless metal belt)
The full width at half maximum of the X-ray diffraction peak of the (111) crystal face and (200) crystal face of the nickel alloy of the endless metal belts of Examples and Comparative Examples is X-ray diffractometer (wavelength: 1.54059 angstroms, trade name: Measurement was performed using a RINT2000 X-ray diffraction apparatus (manufactured by Rigaku Corporation).

(Idle rotation durability test)
The fixing belt according to the example or the comparative example was mounted on the heater heating type belt heating type heating fixing device to obtain a heating fixing device. Using this heat fixing apparatus, an idling test was performed under the following conditions. While adjusting the heater temperature of the heat fixing device to 220 ° C., the pressure roller was pressed against the fixing belt with a predetermined pressure, and the fixing belt was driven to rotate by the pressure roller. As the pressure roller, a pressure roller having an outer diameter of 30 mm, in which an elastic layer made of silicone rubber having a thickness of 3 mm is coated with a 30 μm PFA tube, was used. In this idle rotation durability test, the pressure was 200 N, the nip portion was 8 mm × 230 mm, and the surface speed of the fixing belt was set to 100 mm / s. Grease (HP 300 manufactured by Dow Corning Asia Ltd .; trade name) is applied between the inner surface of the fixing belt and the sliding plate when 0.9 g of the fixing belt is mounted. In the idling durability test, the load torque of the pressure roller required to rotate the fixing belt is measured.
Under the above-mentioned idling durability test, the time until the fixing belt was cracked or broken was visually observed to determine the durability time.
Although 250 hours is required as the minimum endurance time of the fixing belt calculated from the process speed and safety factor of the heat fixing device, the endurance life (endurance time) of the fixing belt of the present invention is set to 500 hours or more and durability Evaluated.

(Actual machine durability test)
By using the image forming apparatus equipped with the full-color LBPLASER SHOT LBP-2040 (trade name) manufactured by Canon Inc., the heat-fixing device used in the above-mentioned idling durability test is used to produce images of over 100,000 sheets. A paper test was performed.
In this actual machine durability test, the pressure applied to the pressure roller was 200 N, the nip was 8 mm x 230 mm, the fixing temperature was set to 200 ° C, the process speed was set to 100 mm / s, and grease was applied between the inner surface of the fixing belt and the sliding plate. (HP 300 manufactured by Dow Corning Asia Ltd .; trade name) is applied when 0.9 g fixing belt is mounted.
A predetermined number of images were drawn out, and the obtained images were visually judged by five evaluators, and evaluated by the determination results of three or more people according to the following criteria.
○: Not significant gloss unevenness compared to the initial image ×: Significant gloss unevenness compared to the initial image

[Example 1]
Nickel sulfamate 450 g / l, cobalt sulfamate 75 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, boric acid 30 g / l, stress reducing agent (sodium saccharin) 0.02 g / l, pit inhibitor ( (Product name: Pitless S: manufactured by Nippon Chemical Industry Co., Ltd.) A nickel electrolytic bath containing 3 g / l was prepared.
Using a stainless steel mother die as a cathode, a nickel alloy film having a predetermined thickness was formed on the surface of the mother die under the conditions of the above nickel electrolytic bath pH 4, electrolytic bath temperature 50 ° C., and current density 6 A / dm ^2. The film was peeled off to produce an endless metal belt having a thickness of 25 μm.
The nickel alloy of this endless metal belt contained 10% by mass of cobalt, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
On the outer peripheral surface of the obtained endless metal belt, a silicone primer (trade name: DY35-067: manufactured by Toray Dow Corning) was applied and dried by a known method to form a primer layer with a thickness of about 1 μm. Through this primer layer, an elastic layer made of 300 μm silicone rubber is applied and heat-cured by a known method using a liquid silicone rubber material having a thermal conductivity of 5.0 × 10 ⁻³ W / cm · ° C. Formed. A silicone adhesive (trade name: TSE3205: manufactured by GE Toshiba Silicones Co., Ltd.) serving as an adhesive layer is applied to the outer periphery, and a PFA tube having a thickness of 25 μm is simultaneously coated and thermally bonded to form a release layer to form a fixing belt. Was made.
Table 1 summarizes the composition of the nickel alloy of the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the idling durability test. Table 2 shows the results of the actual machine endurance paper passing test.

[Example 2]
Nickel sulfamate 450 g / l, cobalt sulfamate 150 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, boric acid 30 g / l, stress reducing agent (sodium saccharin) 0.02 g / l, pit inhibitor ( Pitless S: manufactured by Nippon Chemical Industry Co., Ltd.) An endless metal belt having a thickness of 25 μm was prepared in the same manner as in Example 1 except that a nickel electrolytic bath containing 3 g / l) was used. In the same manner as in Example 1, a fixing belt was produced. The nickel alloy of the endless metal belt contained 20% by mass of cobalt, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Example 3]
Nickel sulfamate 450 g / l, cobalt sulfamate 200 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, boric acid 30 g / l, stress reducing agent (saccharin sodium) 0.02 g / l, pit inhibitor ( Pitless S (manufactured by Nippon Chemical Industry Co., Ltd.) An endless metal belt having a thickness of 20 μm was prepared in the same manner as in Example 1 except that a nickel electrolytic bath containing 3 g / l in concentration was used. A fixing belt was produced in the same manner as described above. The nickel alloy of the endless metal belt contained 40% by mass of cobalt, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Example 4]
Nickel sulfamate 450 g / l, cobalt sulfamate 150 g / l, manganese sulfamate 30 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, boric acid 30 g / l, stress reducing agent (saccharin sodium) 0.02 g / L, an endless metal belt having a thickness of 25 μm was prepared in the same manner as in Example 1 except that a nickel electrolytic bath containing pit inhibitor (pitless S: manufactured by Nippon Chemical Industry Co., Ltd.) at a concentration of 3 g / l was used. Using this, a fixing belt was produced in the same manner as in Example 1. The nickel alloy of the endless metal belt contained 20% by mass of cobalt, 0.2% by mass of manganese, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Example 5]
Nickel sulfate 10.8 g / l, sodium tungstate 32.3 g / l, reducing agent (citric acid) 36.5 g / l, stress reducing agent (saccharin sodium) 0.02 g / l, pit inhibitor (pitless S: Nihon Chemical) (Made by Sangyo Co., Ltd.) The same procedure as in Example 1 was conducted except that a nickel electrolytic bath containing 3 g / l was used and the conditions were as follows: nickel electrolytic bath pH 6.5, electrolytic bath temperature 65 ° C., cathode current density 5 A / dm ^2. An endless metal belt having a thickness of 25 μm was prepared, and a fixing belt was prepared using the endless metal belt in the same manner as in Example 1. The nickel alloy of the endless metal belt contained 30% by mass of tungsten, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Example 6]
An endless metal belt having a thickness of 20 μm was produced in the same manner as in Example 5, and a fixing belt was produced in the same manner as in Example 1 using this. The nickel alloy of the endless metal belt contained 30% by mass of tungsten, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Example 7]
Nickel chloride 16.2 g / l, stannous chloride 159.3 g / l, potassium pyrophosphate 165.2 g / l, PH buffer glycine 18.8 g / l, stress reducing agent (sodium saccharin) 0.03 g / l, Example 1 except that a nickel electrolytic bath containing a pit inhibitor (pitless S: manufactured by Nippon Kagaku Sangyo Co., Ltd.) at a concentration of 3 g / l was used and the conditions were nickel electrolytic bath pH 8 and cathode current density 1 A / dm ^2. Similarly, an endless metal belt having a thickness of 25 μm was produced, and a fixing belt was produced using the endless metal belt in the same manner as in Example 1. The nickel alloy of the endless metal belt contained 45% by mass of tin, 0.005% by mass of sulfur, and 0.015% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Comparative Example 1]
Nickel sulfamate 450 g / l, cobalt sulfamate 5 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, boric acid 30 g / l, stress reducer (saccharin sodium 0.02 g / l, pit inhibitor (pitless S) An endless metal belt having a thickness of 25 μm was produced in the same manner as in Example 1 except that a nickel electrolytic bath containing 3 g / l in concentration was used, and a fixing belt was produced in the same manner as in Example 1 using this. The nickel alloy of the endless metal belt contained 3% by mass of cobalt, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Comparative Example 2]
Nickel sulfamate 450 g / l, cobalt sulfamate 270 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, boric acid 30 g / l, stress reducer (sodium saccharin) 0.02 g / l, pit inhibitor ( Pitless S) An endless metal belt having a thickness of 25 μm was prepared in the same manner as in Example 1 except that a nickel electrolytic bath containing 3 g / l in concentration was used. Produced. The nickel alloy of the endless metal belt contained 60% by mass of cobalt, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Comparative Example 3]
Nickel chloride 16.2 g / l, stannous chloride 189.6 g / l, potassium pyrophosphate 165.2 g / l, PH buffer glycine 18.8 g / l, stress reducing agent (sodium saccharin) 0.03 g / l, An endless shape having a thickness of 25 μm was used in the same manner as in Example 1 except that a nickel electrolytic bath containing a pit inhibitor (pitless S) at a concentration of 3 g / l was used and the conditions were nickel electrolytic bath pH 8 and cathode current density 1 A / dm ^2. A metal belt was produced, and a fixing belt was produced using the metal belt in the same manner as in Example 1. The nickel alloy of the endless metal belt contained 60% by mass of tin, 0.005% by mass of sulfur, and 0.015% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Comparative Example 4]
Nickel sulfate 10.8 g / l, sodium tungstate 58.8 g / l, reducing agent citric acid 36.5 g / l, stress reducing agent (sodium saccharin) 0.02 g / l, pit inhibitor (pitless S) 3 g / l An endless metal belt having a thickness of 25 μm was used in the same manner as in Example 1 except that the nickel electrolytic bath was used at a concentration of 0.15 μm, the electrolytic bath temperature was 6.5 ° C., the electrolytic bath temperature was 65 ° C., and the cathode current density was 5 A / dm ^2. Using this, a fixing belt was produced in the same manner as in Example 1. The nickel alloy of the endless metal belt contained 60% by mass of tungsten, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Comparative Example 5]
Nickel sulfamate 290 g / l, cobalt sulfamate 150 g / l, nickel bromide 7 g / l, cobalt bromide 7 g / l, manganese sulfamate 404.8 g / l, boric acid 30 g / l, stress reducing agent (saccharin sodium) 0 Except using nickel electrolytic bath containing 0.02 g / l, pit inhibitor (pitless S) at a concentration of 3 g / l, nickel electrolytic bath pH 4, electrolytic bath temperature 50 ° C., cathode current density 16 A / dm ² An endless metal belt having a thickness of 25 μm was produced in the same manner as in Example 1, and a fixing belt was produced in the same manner as in Example 1 using this. The nickel alloy of the endless metal belt contained 20% by mass of cobalt, 1% by mass of manganese, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

[Comparative Example 6]
An endless metal belt having a thickness of 25 μm was prepared in the same manner as in Example 2 except that the conditions were a nickel electrolytic bath pH 6 and a cathode current density of 45 A / dm ^2. Produced. The nickel alloy of the endless metal belt contained 20% by mass of cobalt, 0.02% by mass of sulfur, and 0.01% by mass of carbon.
Summary of the composition of the nickel alloy constituting the obtained endless metal belt, the half width of the X-ray diffraction peak of the (111) crystal plane and the (200) crystal plane, the thickness of the endless metal belt, and the results of the idling durability test Table 1 shows the results of the actual machine endurance paper passing test.

  The cobalt content of the nickel alloy of the endless metal belts of Examples 1 to 3 is in the range of 10 to 40% by mass, and the solid solution effect of cobalt appears, and the (111) crystal plane and (200) crystal plane Both the X-ray diffraction peaks have a half width in the range of 0.5 ° to 2 °, and after an idling durability test of 500 hours or more in an idling durability test of a fixing belt manufactured using these endless metal belts. It was confirmed that the durability was good both on the inner surface side of the fixing belt and on both end surfaces of the fixing belt. In particular, in Example 3, the thickness of the endless metal belt is 20 μm, and the flexibility of the fixing belt manufactured using the endless metal belt can be further improved, and the durability is 880 hours, which is excellent in durability. It was.

  The durability of the fixing belt of Example 4 in the idling durability test was 780 hours. From this result, in the fixing belt using the endless metal belt of Example 4, the durability in the idling durability test is of a binary nickel alloy (Example 2) by adding 0.2% by mass of manganese. It turns out that it improves more.

In the endless metal belts made of nickel alloy containing 30% by mass of tungsten of Example 5 and Example 6, the half widths of the X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane are both 0.5 °. In the range of ˜2 °, it was confirmed that any of the fixing belts produced using these has a durability time of 500 hours or more in the idling durability test. In particular, in the fixing belt using the endless metal belt having a thickness of 20 μm in Example 6, a durability time of 720 hours or more was obtained. This is presumably due to the fact that a solid solution effect due to other metal elements was expressed. In Example 6, it is presumed that excellent durability was obtained due to the solid solution effect and the thinning effect.
An endless metal belt made of a nickel alloy containing 45% by mass of tin in Example 7 also has a half-value width of X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane in the range of 0.5 ° to 2 °. It was confirmed that the fixing belt using the endless metal belt showed excellent durability of 650 hours in the idling durability test.

  On the other hand, the endless metal belt made of a nickel alloy containing 3% by mass of cobalt in Comparative Example 1 has an X-ray diffraction peak half-value width of (111) crystal plane of 0.34 ° and smaller than 0.5 °. The fixing belt manufactured using this endless metal belt had a durability time of 250 hours. And since the wear resistance is not sufficient, a torque-up phenomenon due to frictional wear also appeared during the idling durability test. This is presumably because the solid solution effect does not sufficiently develop.

  In the endless metal belt made of a nickel alloy containing 60% by mass of cobalt of Comparative Example 2, the half-value width of the X-ray diffraction peak of the (200) crystal plane was 2.1 ° and exceeded 2 °. The fixing belt produced using the belt had an endurance time of 150 hours in the idling durability test, and cracks occurred at this point. This is presumably due to the tensile stress caused by the solute cobalt in the nickel alloy.

  In the endless metal belt made of a nickel alloy containing 60% by mass of tin in Comparative Example 3, the half-value width of the X-ray diffraction peak of the (200) crystal plane was 2.3 °, exceeding 2 °, and this endless shape. The durability of the fixing belt produced using the metal belt in the idling durability test was 150 hours.

  In the endless metal belt made of a nickel alloy containing 60% by mass of tungsten of Comparative Example 4, the half-value width of the X-ray diffraction peak of the (200) crystal plane is 2.5 °, which exceeds 2 °. The endurance time in the idling durability test of the fixing belt produced using the metal belt was 220 hours. This is presumably because tensile stress was generated by the solute tungsten.

  In the endless metal belt made of a nickel alloy containing 20% by mass of cobalt and 1% by mass of manganese of Comparative Example 5, the half width of the X-ray diffraction peak of the (200) crystal plane is 2.2 °, which is 2 °. The fixing belt manufactured using this endless metal belt had a durability time of 170 hours in the idling durability test. This is presumed to be due to the fact that the internal stress of the nickel alloy became a tensile stress because the manganese solute was forcibly dissolved.

In the endless metal belt made of nickel alloy containing 20% by mass of cobalt of Comparative Example 6, the half-value widths of the X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane are 0.35 °, 0.00 mm, respectively. The full width at half maximum of the X-ray diffraction peak of the (111) crystal plane was 54 °, and the endurance time of the fixing belt produced using this endless metal belt was 180 hours. This is presumably because a solid solution effect does not appear in a nickel alloy obtained under electroforming conditions of a high current density of 45 A / dm ² and a pH value of 6.

  As shown in Table 2, in the image forming apparatus equipped with the heat fixing device including the fixing belts of Example 2, Example 4, Example 5 and Example 7, all had no trouble and 100,000. The end-of-sheet durability test was completed and it was found that the sheet has excellent durability.

  The endless metal belt of the present invention has excellent bending resistance and good durability due to a solid solution effect, and the fixing belt of the present invention produced using this has a small diameter fixing belt. The fixing device including the fixing belt of the present invention is excellent in durability.

FIG. 4 is a schematic diagram for explaining a layer configuration of a fixing belt according to an embodiment of the present invention. FIG. 6 is a schematic diagram for explaining a layer configuration of a fixing belt according to another embodiment of the present invention. It is a schematic diagram which shows the cross section of the heat fixing apparatus of one Embodiment of this invention. It is a schematic diagram which shows the cross section of the heat fixing apparatus of other embodiment of this invention. It is a schematic diagram for demonstrating the change of the X-ray-diffraction peak by internal stress. (A) no internal stress, (b) macroscopic internal stress, (c) microscopic internal stress

Explanation of symbols

1 Metal belt layer
2 Elastic layer 3 Adhesive layer
4 Release layer 10, 20 Fixing belt 200, 300 Heat fixing device 210, 310 Fixing belt 212 Ceramic heater 212 a Heat generation layer 212 b Protective layer 216, 316 Belt guide 222, 322 Pressing rigid stay 230, 330 Pressing member (pressing roller)
230a, 330a Core metal 230b, 330b Elastic layer 240, 340 Sliding plate N Nip portion t Toner image P Recording material 317a, 317b, 317c Magnetic core 318 Excitation coil
319 Insulating material
326 Temperature sensor M driving means

Claims (15)

  An endless metal belt made of a nickel alloy, wherein the nickel alloy is a nickel alloy containing 5% by mass or more of another metal element, and the half width of the X-ray diffraction peaks of the (111) crystal plane and the (200) crystal plane Are both endless metal belts characterized in that they are between 0.5 ° and 2 °.   The endless metal belt according to claim 1, wherein the other metal element is at least one selected from the group consisting of Co, Mn, Sn, W, Cu and Zn.   2. The endless metal belt according to claim 1, wherein the other metal element is at least one selected from the group consisting of Co, Mn, Sn, and W.   The endless metal belt according to claim 1, wherein the content of the metal element other than the nickel alloy is 5 to 50 mass%.   2. The endless metal belt according to claim 1, wherein the nickel alloy contains at least one nonmetallic element selected from the group consisting of sulfur and carbon, and is manufactured by an electroforming method.   6. The endless metal belt according to claim 5, wherein the nickel alloy has a nonmetallic element content of 0.002 to 0.05 mass%.   The endless metal belt according to claim 1, wherein the endless metal belt has a thickness of 10 to 100 μm.   The endless metal belt according to claim 7, wherein the endless metal belt has a thickness of 15 to 60 μm.   A fixing belt comprising the endless metal belt according to claim 1.   The fixing belt according to claim 9, further comprising an elastic layer on the endless metal belt.   The fixing belt according to claim 9, further comprising a release layer on an outer peripheral surface side of the fixing belt.   The fixing belt according to claim 9, further comprising a release layer on an outer peripheral surface side of the fixing belt, and an elastic layer between the release layer and the endless metal belt.   In a heating and fixing apparatus that heats and fixes a recording material on which an unfixed image is held at a nip portion formed by a pair of fixing members each having at least one belt shape, the fixing member having the belt shape includes: A heat-fixing device comprising the endless metal belt according to claim 1.   14. The heat fixing device according to claim 13, further comprising a heater for heating the fixing member having a belt shape.   14. The heat fixing device according to claim 13, further comprising magnetic field generating means for electromagnetically heating a fixing member having a belt shape.

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