JP2011115976A - Multilayer endless tubular belt having electromagnetic induction heat generation layer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endless annular belt which makes a polyimide layer and a metal layer including a heat generation layer have excellent adhesion strength during high temperature fixing even if heat generation is carried out by an electromagnetic induction heat generation method, suppresses the deterioration of durability by the crack, oxidative deterioration, etc., of a metal heating layer by mechanical stress during high speed rotation, and can maintain stable heat generation characteristics over a long period of time. <P>SOLUTION: In the multilayer endless tubular belt, from its inner circumference side toward its peripheral side, the polyimide resin layer A, a nickel layer B, a heating layer C, and a nickel layer D are successively laminated, and the polyimide resin layer A contains a polyimide resin and fine nickel particles. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a multilayer endless tubular belt having an electromagnetic induction heating layer. Specifically, the present invention relates to a fixing member (fixing belt) for electromagnetic induction heating used in an image forming apparatus using an electrophotographic system.

  Polyimide resins are used in various fields by taking advantage of their excellent heat resistance, electrical characteristics, mechanical characteristics, and the like. One of them is application to a functional belt (transfer belt, fixing belt, etc.) for a copying machine.

  In an electrophotographic image forming apparatus, a fixing device that fixes a toner image on the surface of a recording medium by heating and pressurizing employs a heat fixing roll method having a heating halogen heater inside a metal roll. Mainstream. In addition, there is a method in which fixing is performed by bringing a belt-like heater as a heating source into contact with the inner surface of a fixing belt made of an endless belt.

  Furthermore, in response to demands for energy saving, faster copying speed, shorter start-up time, etc., a metal thin film layer is provided on the surface of the polyimide resin film, the metal layer generates heat by electromagnetic induction, and the toner image is heated on the copy paper. A fixing method has been proposed.

  As means for directly laminating the polyimide resin and the metal layer, sputtering, vapor deposition, plating, etc. are generally mentioned, but not only the adhesion strength with the polyimide resin is insufficient, but also the metal heating layer is cracked, cracked, etc. Since the heat generation characteristics due to the generation and further the increase in the resistance of the metal heat generation layer are deteriorated, there is a problem that sufficient durability cannot be obtained.

  For example, Patent Documents 1 to 5 describe endless annular belts having improved adhesion strength between a polyimide resin and a metal layer.

  In Patent Document 1, metal particles (copper particles) are arranged on the surface of a polyimide resin belt, and electroplating is performed using the resin film as an electrode to form a metal thin film on the resin film. It is described that the adhesion strength can be increased. However, if metal particles (copper particles) are present in the molding process of the polyimide resin film, there is a problem that a metal complex is formed and the imidization reaction is inhibited. In addition, there are problems such as deterioration in heat generation characteristics due to oxidative deterioration of the metal heat generation layer and insufficient adhesion to the polyimide resin belt.

  In Patent Literature 2, a polyimide tubular material having nickel powder on the outer surface is electrolytically plated (electrocopper plating) to form a copper plating layer, and then a nickel layer is formed thereon by electronickel plating. Describes a tubular belt provided with a release layer made of a fluororesin (for example, Example 1). However, there are problems of deterioration of heat generation characteristics due to oxidation deterioration of the metal heat generation layer and generation of cracks or cracks.

  Patent Document 3 describes a polyimide endless tubular film in which an aromatic polyamic acid containing a carbonyl nickel powder is rotationally molded and a part of the carbonyl nickel powder is exposed on the outer surface (for example, implementation). Example 1). A polyimide endless tubular film obtained by performing copper electrolytic plating on the outer surface of the film and further nickel electrolytic plating thereon is described (for example, Example 3). However, there are problems of deterioration of heat generation characteristics due to oxidation deterioration of the metal heat generation layer and generation of cracks or cracks.

  In Patent Document 4, a polyimide belt having a dispersed layer of copper fine particles is formed on the surface layer by adsorbing copper ions on the surface of the polyimide belt subjected to alkali treatment and then reducing, and this is formed by electroless copper plating and electrolysis. A fixing belt obtained by copper plating is described (for example, Example 1).

  In Patent Document 5, an outer peripheral surface of a polyimide endless belt is subjected to an alkali etching treatment, and a nickel layer is formed thereon by electroless nickel plating, and a copper layer is formed thereon by electrolytic plating treatment. A fixing belt obtained by forming a nickel layer by electrolytic plating is described (for example, Example A).

  However, in these fixing belts, because only the metal layer generates heat instantaneously and suddenly due to electromagnetic induction action, the durability of the metal heat generation layer deteriorates and the heat generation characteristics deteriorate, or the polyimide films having different expansion coefficients. The adhesion between the layer and the metal layer may be reduced. Polyimide resin belts that can be used in the electromagnetic induction heat fixing system are required to have a copy durability capable of copying hundreds of thousands of sheets under the heat cycle conditions of room temperature and fixing temperature (about 200 ° C), and can be rotated at high speed. Sufficient mechanical strength to withstand is required. However, a polyimide resin belt that satisfies these requirements has not been realized.

JP 2002-248705 A JP 2002-292766 A JP 2003-327723 A JP 2006-71833 A JP 2006-301562 A

  An object of the present invention is to provide a metal heat generation layer caused by mechanical stress during high-speed rotation when the polyimide layer and the metal layer including the heat generation layer have high adhesion strength when heated by an electromagnetic induction heat generation method. It is an object of the present invention to provide an endless annular belt capable of maintaining a stable heat generation characteristic over a long period of time by suppressing a decrease in durability due to cracks, oxidation deterioration, and the like.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have obtained a polyimide resin layer A, a nickel layer B, a heat generation layer C (a layer containing a metal having a lower specific resistance than nickel) from the inner peripheral side to the outer peripheral side. And a nickel layer D, and the polyimide resin layer A includes a polyimide resin and nickel-based fine particles, and has been found to solve the above problems. That is, it has been found that the adhesion between the polyimide resin layer A and the nickel layer B is high, and the mechanical characteristics and the heat generation characteristics are excellent. As a result of further research based on this knowledge, the present invention has been completed.

  The present invention provides the following multilayer endless tubular belt and a method for producing the same.

  Item 1. From the inner peripheral side to the outer peripheral side, the polyimide resin layer A, the nickel layer B, the heat generating layer C (a layer containing a metal having a lower specific resistance than nickel), and the nickel layer D are laminated in this order. A multilayer endless tubular belt comprising a resin and nickel-based fine particles.

  Item 2. Item 2. The multilayer endless tubular belt according to Item 1, wherein the heat generating layer C is a layer containing copper or silver formed by electrolytic plating.

  Item 3. Item 3. The multilayer endless tubular belt according to Item 1 or 2, wherein the nickel layer B has a thickness of 0.1 to 9 µm, and the heat generating layer C has a thickness of 3 to 30 µm.

  Item 4. Item 4. The multilayer endless tubular belt according to Item 1, 2, or 3, wherein nickel-based fine particles in the polyimide resin layer A are unevenly distributed or exposed on a surface portion of the polyimide resin layer A on the nickel layer B side.

  Item 5. Item 5. The multilayer endless tubular belt according to any one of Items 1 to 4, wherein the polyimide resin layer A has a thickness of 40 to 120 µm.

  Item 6. Item 6. The multilayer endless tubular belt according to any one of Items 1 to 5, wherein the polyimide resin layer A further contains conductive carbon black.

  Item 7. Item 7. The multilayer endless tubular belt according to any one of Items 1 to 6, further comprising a silicone rubber layer E on the outer peripheral side.

  Item 8. Item 8. The multilayer endless tubular belt according to any one of Items 1 to 7, further comprising a fluorine-based resin layer F on the outer peripheral side.

  Item 9. A fixing belt comprising the multilayer endless tubular belt according to Item 1.

Item 10. From the inner peripheral side to the outer peripheral side, a manufacturing method of a multilayer endless tubular belt laminated in the order of polyimide resin layer A, nickel layer B, heat generation layer C, and nickel layer D,
(1) Rotating and molding a polyamic acid solution containing nickel-based fine particles to form a polyimide tubular product (polyimide resin layer A) in which nickel-based fine particles are unevenly distributed or exposed on the outer peripheral surface portion;
(2) forming a nickel layer B on the outer peripheral surface of the polyimide tubular article,
(3) a step of forming a heat generation layer C by an electrolytic plating method on the outer peripheral surface of the nickel layer B of the polyimide tubular body on which the nickel layer B is formed; and (4) a polyimide tube on which the metal layer C is formed. Forming a nickel layer D on the outer peripheral surface of the metal layer C of an object,
A method for producing a multilayer endless tubular belt, comprising:

Item 11. The method for producing a multilayer endless tubular belt according to Item 10,
(1) Rotating and molding a polyamic acid solution containing nickel-based fine particles to form a polyimide tubular product (polyimide resin layer A) in which nickel-based fine particles are unevenly distributed or exposed on the outer peripheral surface portion;
(2) a step of forming a nickel layer B on the outer peripheral surface of the polyimide tubular body by an electrolytic plating method or an electroless plating method;
(3) a step of forming a heat generation layer C by an electrolytic plating method on the outer peripheral surface of the nickel layer B of the polyimide tubular body on which the nickel layer B is formed; and (4) a polyimide tube on which the metal layer C is formed. Forming a nickel layer D by an electrolytic plating method or an electroless plating method on the outer peripheral surface of the metal layer C of an object,
A method for producing a multilayer endless tubular belt, comprising:

  In the present invention, a polyimide resin layer A, a nickel layer B, a heat generation layer C (a layer containing a metal having a lower specific resistance than nickel) and a nickel layer D are laminated in this order from the inner peripheral side to the outer peripheral side. A multilayer endless tubular belt characterized in that the resin layer A contains a polyimide resin and nickel-based fine particles. This belt has excellent adhesion strength between the polyimide layer and the metal layer including the heat generation layer when it is heated by the electromagnetic induction heat generation method, and cracks in the metal heat generation layer due to mechanical stress during high-speed rotation. In addition, it is possible to maintain a stable heat generation characteristic over a long period by suppressing a decrease in durability due to oxidative degradation or the like.

The schematic diagram of an electromagnetic induction heating apparatus is shown. 1 shows a cross-sectional view of a multilayer endless tubular belt of the present invention.

  The multilayer endless tubular belt of the present invention is laminated in the order of a polyimide resin layer A, a nickel layer B, a heat generation layer C (a layer containing a metal having a lower specific resistance than nickel), and a nickel layer D from the inner peripheral side to the outer peripheral side. The polyimide resin layer A includes a polyimide resin and nickel-based fine particles. Furthermore, the multilayer endless tubular belt may further have a silicone rubber layer E and / or a fluorine resin layer F on the outer peripheral side of the nickel layer D. Here, the endless belt means a seamless (seamless) tubular film.

Formation of polyimide resin layer A The polyimide resin layer A contains a polyimide resin and nickel-based fine particles. In the polyimide resin layer A, the nickel-based fine particles are preferably unevenly distributed or exposed on the outer surface portion of the polyimide resin layer A on the nickel layer B side. The unevenly distributed or exposed nickel-based fine particles exhibit an anchor effect with the nickel layer B formed on the outer peripheral surface of the polyimide resin layer A. Thereby, the high adhesiveness of the polyimide resin layer A and the nickel layer B is achieved.

  Examples of the polyimide resin contained in the polyimide resin layer A include aromatic polyimide and aromatic polyamideimide.

  Aromatic polyimide is usually produced by condensation polymerization of aromatic tetracarboxylic dianhydride and aromatic diamine or aromatic diisocyanate as monomer components by a known method.

  As aromatic tetracarboxylic dianhydrides, pyromellitic acid, naphthalene-1,4,5,8-tetracarboxylic acid, naphthalene-2,3,6,7-tetracarboxylic acid, 2,3,5,6 -Biphenyltetracarboxylic acid, 2,2 ', 3,3'-biphenyltetracarboxylic acid, 3,3', 4,4'-biphenyltetracarboxylic acid, 3,3 ', 4,4'-diphenyl ether tetracarboxylic acid 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic acid, azobenzene-3,3 ′, 4,4′-tetracarboxylic acid, bis ( 2,3-dicarboxyphenyl) methane, bis (3,4-dicarboxyphenyl) methane, β, β-bis (3,4-dicarboxyphenyl) propane, β, β-bis (3,4) Carboxyphenyl) hexafluoropropane, p- terphenyl-3,3 ', dianhydride and 4,4'-tetracarboxylic acid. Of these, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride and p-terphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride are preferred.

  As aromatic diamines, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,6-diaminotoluene, 2,4-diaminochlorobenzene, m-xylylenediamine, p-xylylenediamine, 1 , 4-diaminonaphthalene, 1,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,4'-diaminobiphenyl, benzidine, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine, 3,4 ' -Diaminodiphenyl ether, 4,4'-diaminodiphenyl ether (ODA), 4,4'-diaminodiphenyl sulfide, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminoazobenzene, 4 , 4'-Diaminodiphenylmethane, β, β-bis (4-amino Nophenyl) propane, 4,4'-diamino-p-terphenyl and the like. Among these, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, p-phenylenediamine, and 4,4′-diamino-p-terphenyl are preferable.

  Examples of the aromatic diisocyanate include compounds in which the amino group in the aromatic diamine component is substituted with an isocyanate group.

  The aromatic polyamideimide is produced by condensation polymerization of trimellitic acid and aromatic diamine or aromatic diisocyanate by a known method. In this case, the same aromatic diamine or aromatic diisocyanate as the above-mentioned aromatic polyimide raw material can be used.

  Nickel-based fine particles can be produced, for example, by a production method such as a carbonyl method, a wet method, an atomization method, or a pulverization method. Among them, nickel obtained by a carbonyl method that has an excellent structure structure and easily exhibits high conductivity. A powder is preferred.

  Considering the anchor effect of the polyimide resin layer A and the nickel layer B and the dispersibility in the polyamic acid solution, the average particle diameter of the nickel-based fine particles is usually 0.1 to 10 μm, preferably 0.2 to It is 8 μm, more preferably 0.5 to 6 μm. Here, the average particle diameter is a value measured by a laser diffraction particle size distribution measuring apparatus free-falling dry method. The content of nickel-based fine particles in the polyimide resin layer A is usually 25 to 75% by weight, preferably 30 to 70% by weight, and more preferably 35 to 60% by weight.

  It is important that the nickel-based fine particles are internally dispersed in the polyimide resin layer A, and the nickel-based fine particles present on the surface portion are in a state where the background is exposed. The presence of nickel-based fine particles with the surface exposed on the surface makes it easier to form the nickel layer B of the thin film provided thereon, and the adhesion between the polyimide resin layer A and the nickel layer B becomes stronger. Accordingly, the larger the surface exposure rate of the nickel-based fine particles, the better the tendency. However, when the exposed portion is too large, a tendency to decrease is observed in terms of adhesion.

  Therefore, for example, when a sample section is prepared with an ion beam or the like and enlarged and observed, the presence of nickel-based fine particles can be confirmed on the surface of the polyimide resin layer A. The degree of nickel exposure on the surface can be quantitatively analyzed by various methods, but in the present invention, it is performed with an EDX (energy dispersive X-ray analyzer). Specifically, in the field of view of 100 μm square in EDX. Four main elements of carbon, oxygen, nitrogen, and nickel are detected, and the detected atomic number concentration of nickel is obtained as a ratio of the total detected amount. The preferable range of the atomic number concentration of nickel in the EDX of the present invention is 10 to 60%, more preferably 15 to 50%, and still more preferably 20 to 32%.

  The multilayer endless tubular belt of the present invention is suitable as a fixing belt, but may be used as a transfer and fixing belt. In this case, in order to impart desired semiconductivity to the polyimide resin layer A, a conductive agent such as carbon black may be added as necessary. Examples of carbon black include ketjen black, furnace black, thermal black, channel black, and the like, and can be appropriately selected according to a target semiconducting level.

  The average particle diameter of the conductive agent (particularly carbon black) is usually 0.1 to 0.5 μm, preferably 0.2 to 0.4 μm. Content of the electrically conductive agent in the polyimide resin layer A is 2 to 40 weight% normally, Preferably it is 5 to 30 weight%, More preferably, it is 8 to 20 weight%.

  The polyimide resin layer A can be formed as follows, for example. A polyamic acid in which the aromatic tetracarboxylic dianhydride and aromatic diamine, which are the raw materials of the aromatic polyimide, are reacted in a solvent to form a polyamic acid solution, and nickel-based fine particles are added thereto to disperse the nickel-based fine particles. An acid solution is obtained. If necessary, a conductive agent such as carbon black may be added to the polyamic acid solution.

  Examples of the solvent for the polyamic acid solution include N-methyl-2-pyrrolidone (hereinafter referred to as “NMP”), N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide. An aprotic organic polar solvent such as hexamethylphosphoamide, 1,3-dimethyl-2-imidazolidinone is used. One or two or more of these solvents may be used. In particular, NMP is preferable.

  The polyamic acid solution is prepared by a known method using the solvent, aromatic tetracarboxylic dianhydride, and aromatic diamine. The above nickel-based fine particles and, if necessary, a conductive agent (particularly, carbon black) can be added thereto, and if necessary, uniformly dispersed using a ball mill or the like.

  The solid content concentration in the prepared polyamic acid solution is usually 10 to 40% by weight, preferably 15 to 30% by weight. The concentration of the nickel-based fine particles is 25 to 75% by weight, preferably 35 to 60% by weight in the solid content. When a conductive agent is included as necessary, the concentration of the conductive agent is 2 to 40% by weight, preferably 8 to 20% by weight in the solid content.

  The obtained polyamic acid solution is diluted with a solvent as necessary to adjust the viscosity. In general, when the viscosity of the solution is low, the added nickel-based fine particles are likely to settle, and the dispersibility deteriorates with the passage of time and tends to be agglomerated. On the other hand, if the viscosity is too high, the added nickel-based fine particles are difficult to be uniformly dispersed even with sufficient stirring. Therefore, it is suitable that the viscosity of the polyamic acid solution is usually in the range of 1.5 to 10.0 Pa · s, preferably 2.5 to 5.0 Pa · s. Thereby, uniform dispersion of nickel-based fine particles can be achieved in the polyamic acid solution.

  The polyimide resin solution to which nickel-based fine particles and, if necessary, carbon black are added is sufficiently stirred and dispersed by a high-speed stirrer. In order to improve dispersibility, a fluorine-based surfactant or the like may be added as necessary.

  Next, the polyamic acid solution is cast into a cylindrical mold (metal drum) and rotationally molded (centrifugal molding) to form a polyimide tubular product (belt).

  As a rotational molding method, for example, a metal drum (both inner surfaces are mirror-finished by chromium plating with Rz = 0.5 μm) is detachably mounted on two variable rotating rollers with a built-in heater, and a roller. There is an indirect rotation method in which the metal drum rotates by the rotation. For heating the metal drum, an external heating method using a heater built in a rotating roller and a far infrared heater is used. Moreover, it is preferable that the organic solvent evaporated by heating is positively exhausted using an exhaust fan.

  A polyamic acid solution is supplied to the inner surface of the metal drum, uniform casting application is performed with centrifugal force generated by the rotation of the metal drum, and heat drying is performed to obtain a polyimide tube (belt). Here, since the nickel-based fine particles of the polyamic acid solution have a specific gravity greater than that of the polyamic acid, the nickel-based fine particles are unevenly distributed or exposed on the outer peripheral surface of the polyimide tubular body (belt) by the centrifugal force at the time of rotational molding. The unevenly distributed or exposed nickel-based fine particles exhibit an anchor effect with the nickel layer B laminated on the outer peripheral surface of the polyimide resin layer A. When carbon black is added as necessary, the specific gravity of carbon black is much smaller than that of nickel particles. Therefore, there is generally little tendency to be unevenly distributed on the outer peripheral surface of the polyimide tubular body (belt), and the carbon black is uniformly dispersed throughout. be able to.

The rotational speed of the rotating drum is usually a speed at which a centrifugal force of 10 to 100 times, preferably 20 to 50 times the gravitational acceleration (9.8 m / s ² ) is applied in order to generate a sufficient centrifugal force. is there. As a result, the nickel-based fine particles are unevenly distributed or exposed on the outer peripheral surface of the polyimide tubular body (belt).

  The rotation of the metal drum is maintained, and the inner surface of the mold is gradually heated to reach about 120 ° C. The temperature rising rate may be about 1 to 2 ° C./min, for example. The temperature is maintained at the above temperature for 20 minutes to 3 hours, and the solvent is volatilized to form a self-supporting belt (primary heating). At this time, it is preferable that the solvent in the belt is not completely removed but is left to some extent (about 10 to 40% by weight in the belt).

  Next, the endless belt obtained by the primary heating is attached to the inner surface of the cylindrical mold, or the endless belt obtained by the primary heating is peeled off from the cylindrical mold and taken out. Separately fitted on a cylindrical mold (metal drum) and put into a hot air drying furnace. Next, as secondary heating, treatment is performed at a temperature of about 280 to 450 ° C. to complete imidization. In this case as well, it is preferable that the temperature is gradually raised to reach that temperature. The time required for this imidization is usually about 1 to 3 hours.

Since the surface resistivity of the obtained polyimide tubular product (belt) needs to have a surface resistivity sufficient to perform nickel electroplating described later, it is usually 1.0 × 10 ⁻⁴ to 1. It is preferably set to 0 × 10 ¹ (Ω / □), preferably 1.0 × 10 ^{−3 to} 1.0 × 10 ⁰ (Ω / □).

  The polyimide tubular product (belt) may be subjected to pretreatment such as etching, plasma treatment, corona treatment, surface polishing and the like on its outer surface before subsequently forming the nickel layer B.

If the surface resistivity is 1.0 × 10 ⁰ (Ω / □) or less, it can be used for the subsequent electrolytic plating treatment of nickel or nickel alloy. When nickel-based fine particles are buried in polyimide resin, that is, when they are covered with polyimide resin and not exposed to the surface (background), the nickel-based fine particles are actively exposed to the surface (background). I do. As this exposure treatment, physical polishing (for example, polishing with an abrasive such as diamond) is recommended as a simple and reliable method.

  From the viewpoint of durability, the thickness of the polyimide resin layer A is usually 40 to 120 μm, preferably 50 to 100 μm, and more preferably 60 to 90 μm. When the thickness is 40 μm or more, when used as a fixing member, it is less likely to undergo plastic deformation partially due to a physical force from the outer periphery to the center of the tubular object. When the thickness is 120 μm or less, the material has a large rigidity and is suitable for this application.

Formation of Nickel Layer B Subsequently, a nickel layer B is formed on the outer peripheral surface of the polyimide tubular product (polyimide resin layer A) produced above. Examples of this method include deposition methods such as sputtering, and electrochemical methods such as electrolytic plating and electroless plating. In terms of obtaining a metal layer having high cost and productivity and high adhesion strength, a method of forming nickel layer B by plating nickel or a nickel alloy by a plating method such as electrolytic plating or electroless plating, particularly electrolytic plating. Is preferred.

  The nickel layer B may be a layer containing nickel metal, and includes a layer made of nickel, a layer made of a nickel alloy, and the like. The nickel layer B contains 10 to 100% by weight, preferably 50 to 100% by weight of nickel metal.

  For example, the electrolytic plating method can be performed using nickel-based fine particles unevenly distributed or exposed on the outer peripheral surface of a polyimide tubular product (polyimide resin layer A) as an electrode (cathode), and the nickel layer B on the outer peripheral surface of the polyimide tubular product. Can be formed. The method of electrolytic plating is not particularly limited, and a known method can be used.

  The thickness of the nickel layer B is usually 0.1 to 9 μm, preferably 0.5 to 8 μm, from the viewpoint of imparting oxidation resistance and the flexibility required for the functional belt. If the thickness is 0.1 μm or more, the effect of oxidation resistance and adhesion of the heat generating layer is suitably exhibited, and if it is 9 μm or less, cracks and cracks due to mechanical stress are less likely to occur.

Formation of Heat Generation Layer C Subsequently, the heat generation layer C is formed by coating the outer peripheral surface of the polyimide tubular body on which the nickel layer B manufactured above is formed with an electromagnetic induction heat generating metal by an electrolytic plating method.

  The heat generation layer C is made of a metal having electromagnetic induction heat generation property and a specific resistance smaller than that of nickel, preferably copper, silver, gold or the like, and more preferably copper.

  The electromagnetic induction heat generation will be described. When a high-frequency alternating current is passed through the coil by a high-frequency power source, a magnetic flux is generated in the coil in a direction perpendicular to the surface around which the coil is wound, depending on the direction of the current. This magnetic flux crosses the heat generating layer C of the multilayer endless tubular belt installed in the vicinity of the coil, thereby generating an eddy current. The amount of eddy electricity generated in the heat generating layer C is converted into heat energy and generates heat. The eddy current is determined by a resistance value determined by the specific resistance and thickness of the material. The smaller the specific resistivity and the thicker the resistance value, the larger the eddy current is generated and converted into thermal energy.

  The reason why the heat generation layer C is formed by using the electrolytic plating method is that the specific resistance of the material itself can be reduced as compared with a deposition method such as sputtering or the electroless plating method. This is because the heat generation layer C formed by the electroplating method has a larger crystal size and crystal orientation (crystal structure is greatly different) than the heat generation layer formed by the deposition method or the electroless plating method. Conceivable.

  In the electroplating method, an electromagnetic induction heat generating metal plate (especially a copper plate) is used as an electrode (anode), and a heat generation layer C is formed on the outer peripheral surface of the nickel layer B of the polyimide tubular body on which the nickel layer B is formed. Can do. The method of electrolytic plating is not particularly limited, and a known method can be used.

For example, first, the polyimide tubular body on which the nickel layer B is formed is connected to the cathode lead wire and the copper plate is connected to the anode lead wire, facing each other at a constant interval, and immersed in the plating bath. The bath temperature is about 20-55 ° C, preferably 25-50 ° C. The cathode current density is about 0.5 A / dm ² or more, preferably 1 to 3 A / dm ² . In order to avoid uneven plating (thickness unevenness of the copper layer), it was conducted after examining the optimum conditions for the shape, number, installation position, stirring state of the plating bath, state of the polyimide tube (fixed or rotating), etc. It is preferable to do.

  The copper plate used as the anode is preferably pure copper, and is preferably as pure as possible.

  The thickness of the heat generating layer C is usually 3 to 30 μm, preferably 5 to 20 μm, from the viewpoint of imparting an appropriate electric resistance value and the flexibility required for the functional belt. If the thickness is 3 μm or more, an eddy current is generated and sufficient heat generation is possible. If the thickness is 30 μm or less, the heat capacity can be kept low and the heat storage phenomenon can be avoided.

Formation of Nickel Layer D Further, the nickel layer D is formed on the outer peripheral surface of the multilayer endless tubular belt (polyimide tubular article on which the heat generating layer C is formed) manufactured as described above. Examples of this method include deposition methods such as sputtering, and electrochemical methods such as electrolytic plating and electroless plating. In terms of obtaining a metal layer having high adhesion strength, a method of forming the nickel layer D by a plating method such as electrolytic plating or electroless plating, particularly by an electrolytic plating method is preferable. When copper that easily oxidizes is used for the heat generation layer C, it is preferable to provide the nickel layer D because oxidation can be suppressed.

  The nickel layer D may be a layer containing nickel metal, and includes a layer made of nickel, a layer made of a nickel alloy, and the like. The nickel layer D contains 10 to 100% by weight, preferably 50 to 100% by weight of nickel metal.

  For example, the electroplating method can be carried out using a multilayer endless tubular belt (polyimide tubular body on which the heat generating layer C is formed) as an electrode (cathode), and the nickel layer D is formed on the outer peripheral surface of the heat generating layer C. be able to. The method of electrolytic plating is not particularly limited, and a known method can be used.

  The thickness of the nickel layer D is usually 0.1 to 20 μm, preferably 1 to 10 μm, from the viewpoint of imparting an appropriate electric resistance value and the flexibility required for the functional belt.

  In this way, the multilayer endless tubular belt of the present invention can be manufactured. The layer structure of the belt is a structure in which polyimide resin layer A / nickel layer B / heating layer C / nickel layer D are laminated in this order from the inner peripheral side to the outer peripheral side.

Other layers In order to prevent the surface of the multilayer endless tubular belt of the present invention in contact with the recording medium from sticking to the unfixed toner image in the molten state at the time of fixing, the surface side (that is, the belt outer peripheral surface) A release layer composed mainly of a low surface energy material can be formed and used on the surface of a certain nickel layer D). Examples of the release layer include a silicone rubber layer E and a fluorine resin layer F.

  The thickness of the release layer is usually in the range of 10 to 100 μm, preferably in the range of 20 to 50 μm, from the viewpoint of wear of the release layer and the flexibility of the belt.

  Examples of the silicone rubber used for the silicone rubber layer E include vinyl methyl silicone rubber, methyl silicone rubber, phenyl methyl silicone rubber, and fluoro silicone rubber.

  Silicone rubber layer E can be formed by applying silicone rubber to the surface of the nickel layer D. Examples of the coating method include a doctor blade method, a spray coating method, and a dip coating method. The thickness of the silicone rubber layer E after drying is usually 50 to 500 μm, preferably 100 to 300 μm.

  Examples of the fluororesin used for the fluororesin layer F include, for example, fluororubber, polytetrafluoroethylene (hereinafter referred to as “PTFE”), perfluoroalkyl vinyl ether copolymer (hereinafter referred to as “PFA”), tetrafluoroethylene. Examples thereof include an ethylene hexafluoropropylene copolymer (hereinafter referred to as “FEP”). Of these, PFA is preferred.

  The fluorine resin layer F can be formed on the surface of the nickel layer D or on the surface of the silicone rubber layer E obtained above. For example, the fluorine-based resin layer F can be formed by coating the outer surface of the belt with a fluorine-based resin tube and firing at 200 to 300 ° C. as necessary. Usually, a shrink tube of fluororesin is used and can be manufactured by extrusion. The thickness of the fluororesin layer F is usually 10 to 100 μm, preferably 15 to 50 μm.

  Specific examples of the layer structure of the belt include the following laminated structure from the inner peripheral side to the outer peripheral side.

Polyimide resin layer A / nickel layer B / heating layer C / nickel layer D / silicone rubber layer E,
Polyimide resin layer A / nickel layer B / heat generation layer C / nickel layer D / fluorine resin layer F or polyimide resin layer A / nickel layer B / heat generation layer C / nickel layer D / silicone rubber layer E / fluorine resin layer F.

Fixing Belt The multilayer endless tubular belt of the present invention can be used as a fixing belt or a fixing / transfer belt of a known electromagnetic induction heating type fixing device (electromagnetic induction heating fixing device). The belt of the present invention is excellent in mechanical strength even when used for a long period of time and does not deteriorate in heat generation characteristics, so that high image quality can be stably obtained. And since the adhesiveness of the polyimide resin layer A and a metal layer (nickel layer B) is strong, it is excellent also in durability.

  Next, the present invention will be specifically described, but the present invention is not limited thereto.

  The solid content concentration, surface resistivity, adhesion, electromagnetic induction heat generation property, and atomic number concentration of the polyamic acid solution were measured as follows.

[Solid content concentration of polyamic acid solution]
The solid content concentration of the polyamic acid solution is a value calculated as follows. The sample is precisely weighed in a heat-resistant container such as a metal cup, and the weight of the sample at this time is defined as A (g). Put the heat-resistant container with the sample in the electric oven, heat and dry while heating up in order of 120 ℃ × 15min, 180 ℃ × 15min, 260 ℃ × 30min, and 280 ℃ × 30min. The weight of the solid content (solid content weight) is defined as B (g). The values of A and B of five samples for the same sample were measured (n = 5) and applied to the following equation to determine the solid content concentration. The average value of the five samples was adopted as the solid content concentration.
Solid content concentration = B / A x 100 (%)

[Surface resistivity (ρs; Ω / □)]
The surface resistivity was measured under the conditions of a load of 2.0 kg, a voltage of 10 V, and a charge time of 10 seconds using a four-probe electrode (for example, Loresta manufactured by Mitsubishi Chemical Corporation) in an environment of 23 ° C. and 55% RH. . A total of 16 points were measured on the outer surface of the belt at four points at equal intervals in the circumferential direction and four points at equal intervals in the axial direction, and the average value was expressed.

[Adhesion]
The belt samples obtained in Examples and Comparative Examples were put into a heat dryer, heated to 200 ° C., heated at that temperature for 20 minutes, and then allowed to cool to room temperature. The peel strength of each sample was measured by a T peeling method according to IPC-FC-241B with a width of 10 mm and a length of 50 mm. The peel strength is usually required to be 0.6 kg / cm or more from the viewpoint of durability evaluation results with an actual machine.

[Electromagnetic induction heat generation]
The belt was fitted to a heat insulating roller, and an electromagnetic induction heating device was placed facing the belt sample with a gap of 0.2 mm. The heat insulation roller was rotated at 15 (min ⁻¹ ), and 120 W AC power was passed through the coil of the electromagnetic induction heating device, and the black fluorine surface was measured with a thermometer (PT-2LD, manufactured by Optex Corporation). Using a device that can automatically adjust the coil output so that the surface temperature becomes 200 ° C., the measurement was performed continuously for 3 hours.

[Atom number concentration of polyimide resin layer A]
The amount of nickel exposed on the surface was measured under the following conditions using an EDX (energy dispersive X-ray analyzer) (7593-H type, manufactured by Horiba, Ltd.).

  Measurement was performed at process time 6 in the mapping mode. The sample was prepared by gold deposition at 5 nm. The acceleration voltage in EDX was 15 kV, the irradiation time was 5 minutes, and the distance between the lens and the sample was 15 mm.

Example 1 Sputtering Use A polyamic acid solution (solution viscosity 1.8) having a solid content concentration of 14.5% by weight by polycondensation reaction of biphenyltetracarboxylic dianhydride (BPDA) and p-phenylenediamine (PPD) in N-methylpyrrolidone solvent. Pa · s) was obtained. To 1 kg of this polyamic acid solution, 65 g of carbonyl nickel powder (nickel powder obtained by carbonyl method, particle size: 2.0 to 3.0 μm) was added and sufficiently dispersed with a high-speed stirrer. The solid content concentration in the obtained polyamic acid solution was 19.7 wt%, and the carbonyl nickel powder concentration in the solid content was 31.0 wt%.

  56 g of this polyamic acid solution was uniformly applied to a metal drum (inner diameter 62 mm, width 500 mm). Next, as the drum was heated, the rotation was gradually accelerated, and when it reached 80 rad / s (centrifugal force 20 times the gravitational acceleration), the temperature was increased to 150 ° C. while maintaining this. Centrifugation was performed for 120 minutes under this rotation and temperature. Then, the solid tubular film was taken out from the drum. The obtained film was a polyamic acid film containing about 30 wt% of N-methylpyrrolidone (solvent).

Next, in order to remove the remaining solvent along with imidation of the polyamic acid film, this was inserted into a cylindrical mold having R _Z = 3.0 μm, an outer diameter of 60 mm, and a length of 420 mm and put into a hot air dryer. It reached 450 ° C. in 120 minutes and heated at that temperature for 30 minutes. Finally, it was cooled to room temperature and extracted from the mold. The obtained film was a completely imidized metal powder-filled polyimide endless tubular film having a thickness of 60 ± 3 μm, an inner diameter of 60 mm, and a length of 420 mm. The surface resistivity was stable in the range of 0.25 to 0.45Ω / □.

  The surface exposed nickel amount was measured using EDX (energy dispersive X-ray analyzer). As a result, the atomic number concentration was 20 to 22%.

Next, the surface of this endless tubular film was pretreated (after degreasing and cleaning and then glow discharge), and then nickel was sputtered on the treated surface under the following conditions to form a thin film nickel layer. The target is a pure nickel plate having a width of 100 mm and a length of 400 mm, fixed vertically to the endless tubular film and fixed to the wall. The degree of vacuum is 10 ⁻³ Torr by argon substitution, the temperature in the vacuum chamber is 100 ° C. The distance from the surface was 15 mm, and the turntable was sputtered at an output voltage of 6.5 W / cm ^{2 for} 15 minutes while rotating at a speed of 1 m / min. This thin film nickel layer was 0.15 μm.

Next, copper electroplating was performed using the endless film with a thin film nickel layer as a cathode and a pure copper plate as an anode under the following conditions to form a copper thick film layer. First, the belt was disposed in the plating bath so as to give a circular rotation whose speed was variable, and a stirring propeller was disposed. In the bath, an electrolyte containing copper sulfate (200 g / L) and sulfuric acid (50 g / L), which do not contain any brightener, as a main component was placed in a substantially filled state. And while starting stirring and rotation, it heated and raised the bath temperature to 40 degreeC. After rotating and adjusting the endless film with a thin film nickel layer to 6 (min ⁻¹ ), current was passed through both electrodes. The current density loaded on the cathode was set to 1.0 A / dm ² and overelectrolytic plating was performed for 15 minutes. And it took out from the bathtub and washed thoroughly with water and dried. When the thickness of the copper layer was measured, it was 5.6 ± 0.3 μm.

  Furthermore, nickel electrolytic plating was performed to form a nickel layer having a thickness of 0.5 μm on the surface of the copper layer, and a thin nickel layer provided on both sides of the copper layer and the copper layer was formed.

  Next, a fixing belt having a black fluororesin layer F on its surface was produced by covering a conductive fluorine (PFA) shrinkable tube (black) and baking at 380 ° C. The thickness of the fluororesin layer F was 29.8 μm.

Example 2 Chemical plating (electroless plating)
The surface of the metal powder-filled polyimide endless tubular film obtained in Example 1 was cut with diamond under the following conditions using an ultra-precision lathe device. The cutting depth was 10 μm, the rotation speed was 4000 (min ⁻¹ ), the feed was 0.07 (mm / rev), and the roughness of the cutting surface was finished to Rz = 0.47. Both ends of this surface-cut film were cut by 20 mm, and the surface exposed nickel amount was also measured using EDX (energy dispersive X-ray analyzer). As a result, the atomic number concentration was 22 to 24%. The surface resistivity was stable in the range of 0.25 to 0.45Ω / □.

  The endless tubular film was chemically plated with nickel under the following conditions to provide a thin nickel layer. First, palladium is provided by a generally known (catalyst) accelerator method, and then nickel sulfate (25 g / L), citric acid (20 g / L) and sodium hypophosphite (20 g / L) are added. It was immersed in an electroless plating bath (adjusted to pH 9 with a brightener) whose temperature was adjusted to 38 ° C. as a main component. The immersion time was 3 minutes, and stirring was sufficiently performed during that time. After the plating, it was thoroughly washed with water and dried. The film thickness formed here was 0.6 μm.

Next, copper electroplating was performed under the following conditions using the endless belt with a thin film nickel layer as a cathode and a pure copper plate as an anode to form a copper thick film layer. First, the belt was disposed in the plating bath so as to give a circular rotation whose speed was variable, and a stirring propeller was disposed. In the bath, an electrolyte containing copper sulfate (200 g / L) and sulfuric acid (50 g / L), which do not contain any brightener, as a main component was placed in a substantially filled state. And while starting stirring and rotation, it heated and raised the bath temperature to 40 degreeC. After rotating the endless belt with a thin film nickel layer to 6 (min ⁻¹ ), current was passed through both electrodes. The current density loaded on the cathode here was 1.0 A / dm ² and overelectrolytic plating was performed for 30 minutes. And it took out from the bathtub and washed thoroughly with water and dried. Here, when the thickness of the copper layer was measured, it was 10.6 ± 0.8 μm.

  Further, chemical plating of nickel was performed to form a nickel layer having a thickness of 1 μm on the surface of the copper layer, and a thin nickel layer provided on both sides of the copper layer and the copper layer was formed.

  Next, liquid silicone rubber (KE3491) manufactured by Shin-Etsu Chemical Co., Ltd. was applied by a doctor blade method to a thickness of 200 μm, and a fixing belt having a black silicone rubber layer E on the surface was produced.

Example 3 Electroplating The surface of the metal powder-filled polyimide endless tubular belt obtained in Example 1 was cut in the same manner as in Example 2 using an ultra-precision lathe device. The surface resistivity was stable in the range of 0.20 to 0.35Ω / □. The surface exposed nickel amount was measured using EDX (energy dispersive X-ray analyzer). As a result, the surface dispersed nickel atom number concentration was 22 to 24%.

  Next, nickel electroplating was performed using the endless tubular belt as a cathode to form a nickel layer having a thickness of 6 μm. Thereafter, copper electrolytic plating was performed using the pure copper plate as an anode under the following conditions. The endless tubular belt was placed in a state where it could be rotated in the plating bath, and a propeller requiring stirring was placed. Then, while rotating the endless tubular belt, electricity was passed through both electrodes to form a copper layer having a thickness of 10 ± 1.0 μm.

  Furthermore, nickel electrolytic plating was performed to form a nickel layer having a thickness of 1 μm on the surface of the copper layer, and a thin nickel layer provided on both sides of the copper layer and the copper layer was formed.

  Next, a liquid silicone rubber (KE3491) manufactured by Shin-Etsu Chemical Co., Ltd. was applied by a doctor blade method to a thickness of 200 μm, and a silicone rubber layer E was formed on the surface. Thereafter, a conductive fluorine (PFA) shrinkable tube (black) was covered and baked at 380 ° C., whereby a fixing belt having a black fluororesin layer F on the surface was produced. The thickness of the fluororesin layer F was 29.9 μm.

Example 4 Electroplating Para-terphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride (TPDA) 100 mol% with respect to the total carboxylic dianhydride component, and the total aromatic diamine component In contrast, 70 mol% of 4,4′-diamino-p-terphenyl and 30 mol% of 4,4′-diaminodiphenyl ether (DADE) are approximately equimolar amounts of the carboxylic dianhydride component and the aromatic diamine component. Was then polymerized in N-methyl-2-pyrrolidone to obtain 1 kg of a polyamic acid solution having a solid content concentration of 16% by weight (solution viscosity of 5 Pa · s).

  To this polyamic acid solution, 22 g of oil furnace carbon black and 100 g of N-methyl-2-pyrrolidone were added, and the carbon black was uniformly dispersed by a ball mill to prepare a carbon black-dispersed polyamic acid solution. The solid content concentration of this solution was 16.2% by weight, and the carbon black content in this solid content weight was 12.1% by weight. The average particle size of carbon black in the solution was 0.28 μm, and the maximum particle size was 0.51 μm.

  Next, 90 g of carbonyl nickel powder (particle size: 5.0 to 8.0 μm) was added and sufficiently dispersed with a high-speed stirrer. The solid content concentration in the obtained polyamic acid solution was 22.4% by weight, the concentration of carbonyl nickel powder in the solid content was 33.1% by weight, and the concentration of carbon black was 8.1% by weight. there were.

  40 g of this polyamic acid solution was uniformly applied in a metal drum (inner diameter 40 mm, width 500 mm). Next, as the drum was heated, the rotation was gradually accelerated, and when it reached 100 rad / s (centrifugal force 31.6 times the gravitational acceleration), the temperature was increased to 150 ° C. while maintaining this. Centrifugation was performed for 90 minutes under this rotation and temperature. Next, this tubular product is put into a high-temperature heating furnace while adhering to the inner peripheral surface of the cylindrical mold, and the temperature is raised to 320 ° C. over 150 minutes (temperature increase rate: about 1.33 ° C./min). Polyimide conversion was completed by heating at 60 ° C. for 60 minutes. Then, it cooled to room temperature and peeled from the metal mold | die inner surface. The obtained belt was a completely imidized metal powder-filled polyimide endless tubular belt having a thickness of 70 ± 3 μm, an inner diameter of 40 mm, and a length of 480 mm. The surface resistivity was stable in the range of 0.20 to 0.25Ω / □. The surface exposed nickel amount was measured using EDX (energy dispersive X-ray analyzer). As a result, the atomic number concentration was 30 to 32%.

  After that, after surface cutting in the same manner as in Example 3, the layers were formed in the order of a nickel layer (6 μm), a copper layer (10 μm), and a nickel layer (1 μm) on a polyimide endless tubular belt by electrolytic plating.

  Next, a liquid silicone rubber (KE3491) manufactured by Shin-Etsu Chemical Co., Ltd. was applied by a doctor blade method to a thickness of 200 μm, and a silicone rubber layer E was formed on the surface. Thereafter, a conductive fluorine (PFA) shrinkable tube (black) was covered and baked at 380 ° C., whereby a fixing belt having a black fluororesin layer F on the surface was produced. The thickness of the fluororesin layer F was 29.9 μm.

Comparative Example 1 When there is no nickel layer on the substrate As in Example 1, copper electroplating was performed under the following conditions using an endless tubular belt as a cathode and a pure copper plate as an anode. First, an endless tubular belt was placed in a state where it could be rotated in a plating bath, and a propeller for stirring was placed. Then, while rotating the endless tubular belt, electricity was passed through both electrodes to form a copper layer having a thickness of 10 ± 1.0 μm. Furthermore, nickel electrolytic plating was performed to form a nickel layer having a thickness of 0.5 μm on the surface of the copper layer.

  Next, a fixing belt having a black fluororesin layer F on its surface was produced by covering a conductive fluorine (PFA) shrinkable tube (black) and baking at 380 ° C. The thickness of the fluororesin layer F was 29.9 μm.

Comparative Example 2 When there are no nickel-based fine particles in the polyimide resin layer Biphenyltetracarboxylic dianhydride (BPDA) and p-phenylenediamine (PPD) are subjected to a condensation polymerization reaction in N-methylpyrrolidone solvent to obtain a solid content concentration of 14.5% by weight. A polyamic acid solution (solution viscosity 1.8 Pa · s) was obtained. To 1 kg of this polyamic acid solution, 25 g of ketjen black having a particle size of 0.1 to 2.0 μm was added and sufficiently dispersed with a high-speed stirrer. The solid content concentration of the obtained polyamic acid solution was 20% by weight, and the ketjen black powder was 12.2% by weight in the solid content of the polyamic acid solution. An endless annular belt was formed in the same manner as in Example 1 using 55 g of this polyamic acid solution.

  The obtained belt was a completely imidized polyimide endless tubular belt, and the thickness of the belt was 60 ± 3 μm, the inner diameter was 60 mm, and the length was 420 mm. However, the surface resistivity did not fall below 1.0Ω / □, and the surface resistivity sufficient for applying nickel electrolytic plating could not be expressed.

  On the other hand, nickel was sputtered under the same conditions as in Example 1 to form a thin film nickel layer (0.15 μm). Copper electroplating was performed under the following conditions using an endless tubular belt formed with a thin nickel layer as a cathode and a pure copper plate as an anode. The endless tubular belt was placed in a state where it could be rotated in the plating bath, and a stirring propeller was placed. Then, electricity was passed through both electrodes while rotating the endless tubular belt to form a copper layer having a thickness of 10 ± 1.0 μm. Furthermore, nickel electrolytic plating was performed to form a nickel layer having a thickness of 0.5 μm on the surface of the copper layer.

  Next, a fixing belt having a black fluororesin layer F on its surface was produced by covering a conductive fluorine (PFA) shrinkable tube (black) and baking at 380 ° C. The thickness of the fluororesin layer F was 29.9 μm.

Comparative Example 3 When the polyimide resin layer is free of nickel-based fine particles The outer peripheral surface of the endless tubular belt obtained in Comparative Example 2 was subjected to alkali etching treatment. Thereafter, a nickel layer was formed on the belt surface using electroless plating as shown in Example 2. The thickness of the obtained nickel layer was 6 μm. Copper electroplating was performed under the following conditions using the endless tubular belt on which the nickel layer was formed as a cathode and a pure copper plate as an anode. The endless tubular belt was placed in a state where it could be rotated in the plating bath, and a stirring propeller was placed. Then, electricity was passed through both electrodes while rotating the endless tubular belt to form a copper layer having a thickness of 10 ± 1.0 μm. Furthermore, nickel electrolytic plating was performed to form a nickel layer having a thickness of 0.5 μm on the surface of the copper layer.

  Next, a fixing belt having a black fluororesin layer F on its surface was produced by covering a conductive fluorine (PFA) shrinkable tube (black) and baking at 380 ° C. The thickness of the fluororesin layer F was 29.9 μm.

Comparative Example 4 When there is no copper layer As in Example 1, an endless tubular belt was used as a cathode, and nickel electroplating was performed to form a nickel layer of 10 ± 1.0 μm.

  Next, a fixing belt having a black fluororesin layer F on its surface was produced by covering a conductive fluorine (PFA) shrinkable tube (black) and baking at 380 ° C. The thickness of the fluororesin layer F was 29.9 μm.

1: Endless annular belt 2: Insulating roller 3: Electromagnetic induction heating device 4: Radiation thermometer
A: Ni-containing polyimide resin layer B: Ni layer C: Heat generation layer D: Ni layer E: Silicone rubber layer F: Fluorine resin layer

Claims (11)

From the inner peripheral side to the outer peripheral side, the polyimide resin layer A, the nickel layer B, the heat generation layer C (a layer containing a metal having a lower specific resistance than nickel) and the nickel layer D are laminated in this order, and the polyimide resin layer A is a polyimide resin. And a multilayer endless tubular belt comprising nickel-based fine particles. The multilayer endless tubular belt according to claim 1, wherein the heat generating layer C is a layer containing copper or silver formed by an electrolytic plating method. 3. The multilayer endless tubular belt according to claim 1, wherein the nickel layer B has a thickness of 0.1 to 9 μm, and the heat generating layer C has a thickness of 3 to 30 μm. 4. The multilayer endless tubular belt according to claim 1, wherein the nickel-based fine particles in the polyimide resin layer A are unevenly distributed or exposed on a surface portion of the polyimide resin layer A on the nickel layer B side. The multilayer endless tubular belt according to any one of claims 1 to 4, wherein the polyimide resin layer A has a thickness of 40 to 120 µm. The multilayer endless tubular belt according to any one of claims 1 to 5, wherein the polyimide resin layer A further contains conductive carbon black. The multilayer endless tubular belt according to any one of claims 1 to 6, further comprising a silicone rubber layer E on an outer peripheral side. The multilayer endless tubular belt according to any one of claims 1 to 7, further comprising a fluorine-based resin layer F on an outer peripheral side. A fixing belt comprising the multilayer endless tubular belt according to claim 1. From the inner peripheral side to the outer peripheral side, a polyimide resin layer A, a nickel layer B, a heat generating layer C and a nickel layer D are laminated in this order, a method for producing a multilayer endless tubular belt,
(1) Rotating and molding a polyamic acid solution containing nickel-based fine particles to form a polyimide tubular product (polyimide resin layer A) in which nickel-based fine particles are unevenly distributed or exposed on the outer peripheral surface portion;
(2) forming a nickel layer B on the outer peripheral surface of the polyimide tubular article,
(3) a step of forming a heat generation layer C by an electrolytic plating method on the outer peripheral surface of the nickel layer B of the polyimide tubular body on which the nickel layer B is formed; and (4) a polyimide tube on which the metal layer C is formed. Forming a nickel layer D on the outer peripheral surface of the metal layer C of an object,
A method for producing a multilayer endless tubular belt, comprising: A method for producing a multilayer endless tubular belt according to claim 10,
(1) Rotating and molding a polyamic acid solution containing nickel-based fine particles to form a polyimide tubular product (polyimide resin layer A) in which nickel-based fine particles are unevenly distributed or exposed on the outer peripheral surface portion;
(2) a step of forming a nickel layer B on the outer peripheral surface of the polyimide tubular body by an electrolytic plating method or an electroless plating method;
(3) a step of forming a heat generation layer C by an electrolytic plating method on the outer peripheral surface of the nickel layer B of the polyimide tubular body on which the nickel layer B is formed; and (4) a polyimide tube on which the metal layer C is formed. Forming a nickel layer D by an electrolytic plating method or an electroless plating method on the outer peripheral surface of the metal layer C of an object,
A method for producing a multilayer endless tubular belt, comprising:

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