JP4832099B2 - Electroformed cylindrical nickel belt, manufacturing method thereof, heat fixing belt base, heat fixing belt, and electrophotographic apparatus - Google Patents

Description

  The present invention relates to an electroformed cylindrical nickel belt and a method for manufacturing the same, and more particularly to a cylindrical nickel belt suitable as a heat fixing belt incorporated in a heat fixing unit of an electrophotographic apparatus.

  Conventionally, as a heating and fixing belt used in an electrophotographic image forming apparatus such as a copying machine or a laser printer, a cylindrical seamless nickel belt manufactured by electroforming (electroformed cylindrical nickel belt or electroformed nickel) Belts) are used as substrates. This base body made of an electroformed cylindrical nickel belt has a drawback that it is cracked when it is repeatedly used at a temperature of 160 to 200 ° C. in the heat fixing process.

  One of the causes is that an organic brightener containing sulfur is used in the electrolyte composition used when electrocasting a cylindrical nickel belt made by electroforming. About 0.01 to 0.02% by weight, and therefore, it is easy to cause sulfur embrittlement that becomes brittle when heat near 200 ° C. is continuously applied. Another cause is that the firing temperature when forming the PFA fluororesin release layer on the surface of the electroformed cylindrical nickel belt substrate is as high as 340 to 350 ° C., and the holding time is 20 to 30 minutes. In this case, sulfur brittleness is likely to occur.

  Therefore, when an electrocast cylindrical nickel belt using an organic brightener containing sulfur is used as the base of the heat fixing belt, it is necessary to improve heat resistance and durability against bending.

  In order to improve heat resistance and durability, there is a proposal to use an endless electroformed sheet having a micro Vickers hardness of 450 to 650 made of a nickel-manganese alloy containing 0.05 to 0.6% by weight of manganese as a substrate. (For example, refer to Patent Document 1). However, when 0.05% by weight or more of manganese is contained, there is a drawback that the micro Vickers hardness becomes too high and it becomes difficult to secure a nip width for fixing due to lack of flexibility.

  Further, an electroformed nickel belt having an intensity ratio of a crystal orientation plane represented by a ratio of a peak intensity at (200) to a peak intensity at (111) plane measured by X-ray diffraction is 0.6 or more (For example, refer to Patent Document 2). However, the formation of the electrodeposited film with a tendency to show the layered orientation referred to here is a low current region using the second brightener, and the deposited amount of the electrodeposited film is 0.4 to 0.6 μm per minute. In order to obtain a film thickness of 30 μm, which is normally used as a nickel belt, an electroforming time of 50 minutes or more is required, which is highly accurate compared to the electroforming process in which the amount of deposited film is 1 μm per minute. Since the number of production, equipment space, equipment cost, utility, etc. of a highly durable electroformed metal mother mold is increased and the productivity is reduced, the equipment cost corresponding to the production of the electroformed nickel belt having the strength ratio is increased.

  Further, an electroformed nickel belt containing at least one metal element belonging to Group 2, Group 3, Group 4, Group 5 of the periodic table in a mass fraction of 10 to 10,000 ppm, and the metal element An electroformed nickel belt made of thallium, lead, bismuth, tin, calcium, zinc, aluminum, silicon, antimony, or 0.01 to 0.50% by mass of manganese as another metal element in addition to the metal element In addition, the electroformed nickel belt to be contained in the electroformed nickel belt, the electroformed nickel belt having a sulfur content of 0.05% by mass or less, and the electroformed nickel belt having a crystal orientation plane. An electroformed nickel belt having a strength ratio of I (200) / I (111) ≧ 0.6, and further, the electroformed nickel belt having a Vickers hardness (VH) of The electroformed nickel belt is 00 to 480 there is proposed a substrate (e.g., see Patent Document 3).

However, 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 has low printing durability. In addition, as in the case of the above-mentioned Patent Document 2, the formation of the electrodeposited film with a tendency to show a layered orientation in which the strength ratio of the crystal orientation plane is 0.6 or more depends on the composition of the electrolytic solution, and the first brightener is used. When the main component is used, the electrolytic current density must be 8 A / dm ² or more in order to make the intensity ratio 0.6 or more, and many protrusion defects are generated, which becomes the starting point of cracks. In addition, when a second brightener is added and the electrodeposited film has a layered structure with a crystal orientation plane strength ratio of 0.6 or more, as described above, the strength ratio corresponding to the production of an electroformed nickel belt can be obtained. Cause an increase in equipment costs.

Further, in a fixing belt having at least a release layer and a nickel electroformed metal layer, the nickel electroformed crystal orientation of the (200) plane preferential growth having a crystal orientation ratio I (200) / I (111) of 3 or more. There is a proposal that the micro Vickers hardness is 280 to 450 (see, for example, Patent Document 4). However, as in the case of Patent Document 2 described above, the formation of an electrodeposited film with a tendency to exhibit a layered orientation is a low current region using the second brightener, and the amount of deposited electrodeposited film is 0.00% per minute. Compared to the electroforming process in which the deposition amount of the deposited film is 1.0 μm / min, it is an area of 4 to 0.6 μm. There is a problem that causes an increase.
JP-A-9-34286 JP 2002-206188 A JP 2002-241984 JP 2002-258648 A

  The present invention has been made in view of the above, and is used repeatedly at a temperature of 160 to 200 ° C. in a heat fixing process in an electroformed cylindrical nickel belt containing sulfur used as a base of a heat fixing belt. No cracks occur, and the firing temperature for forming the fluororesin release layer on the surface of the electroformed cylindrical nickel belt substrate is 340 to 350 ° C., and the holding time is 20 to 30 minutes. Provided is an electroformed cylindrical nickel belt having suppressed printing durability and sulfur brittleness, and an electrophotographic apparatus provided with a heat fixing unit using a heat fixing belt based on the nickel belt. The purpose is to do.

The inventors of the present invention diligently studied the above problems, and as a result of adding manganese in the range of hardness Hv 480 to 530, the mechanical strength was improved without significantly increasing the (200) plane peak. The inventors have found that a cylindrical nickel belt can be obtained and have reached the present invention. That is, according to the present invention, the following means (1) to (10) are provided.
(1) An electrocast cylindrical nickel belt, the strength ratio of the metal crystal orientation plane expressed by the ratio of the peak intensity at the (200) plane to the peak intensity at the (111) plane measured by X-ray diffraction [I (200) / I (111)] is in the range of 0.4 to 0.5, and the sulfur content is 0.01 to 0.02% by mass of sulfur contained in the nickel electrodeposited film. An electroformed cylindrical nickel belt characterized by containing manganese in an amount exceeding 0.05% by mass.
(2) In an electroforming method in which a nickel electrodeposition film is formed on the surface of a cylindrical metal matrix using an electrolytic solution containing nickel sulfamate, the electrolytic solution comprises at least the following compositions 1 to 4. A method for producing an electroformed cylindrical nickel belt according to claim 1.
1 Nickel sulfamate 450 to 550 g / l
2 Boric acid 30-40g / l
3 Naphthalene sodium lisulfonate 500 to 1500ppm
4 Manganese sulfamate 0.05 to 0.2 g / l
(3) The method for producing an electroformed cylindrical nickel belt as described in (2) above, wherein electrodeposition is performed at a current density of 5 to 7 A / dm ² .
(4) The method for producing an electroformed cylindrical nickel belt as described in (2) above, wherein the cylindrical metal matrix is mirror-finished with a surface roughness Rz of 0.03 to 0.1 μm.
(5) The method for producing an electroformed cylindrical nickel belt according to (2) above, wherein a seamless pipe of SUS304TB pipe (JIS G 3463 establishment 1994) is used as the cylindrical metal matrix.
(6) The above (2), characterized in that electrodeposition is performed with a distance between electrodes of 100 to 120 mm between a cylindrical metal matrix with an auxiliary electrode attached to the lower end serving as a cathode and a titanium anode plate serving as an anode. A process for producing the electroformed cylindrical nickel belt as described.
(7) When peeling the nickel electrodeposition film formed on the surface of the cylindrical metal matrix, the electrodeposition stress of the electrodeposition film is peeled by applying a compressive stress in the range of 0 to -50 N / mm ^2. The method for producing an electroformed cylindrical nickel belt as described in (2) above.
(8) The ends of the electroformed cylindrical nickel belt described in (1) above or the electroformed cylindrical nickel belt manufactured by the manufacturing method described in any one of (2) to (7) above A belt base for heat-fixing, which is cut by an opposing roller blade and has a cutting step of 0 to 0.05 mm.
(9) A heat-fixing belt, wherein a silicone rubber layer and a fluororesin release layer are formed on the surface of the substrate according to (8).
(10) An electrophotographic apparatus comprising a heat fixing unit incorporating the heat fixing belt described in (9) above.

  According to the electroformed cylindrical nickel belt of the present invention, the above-described sulfur embrittlement can be suppressed and the transition of nickel metal crystals can be suppressed to increase the mechanical strength. Even if it is repeatedly used at a temperature of up to 200 ° C., it does not crack, and the high temperature of 340 to 350 ° C. and 20 to 30 minutes for forming a fluororesin release layer on the surface of the electroformed cylindrical nickel belt substrate It is possible to provide an electroformed cylindrical nickel belt having printing durability despite the firing.

  Further, according to the method for producing an electroformed cylindrical nickel belt of the present invention, the peak intensity ratio [I (200) / I (111)] of the crystal orientation plane described above is in the range of 0.4 to 0.5. It is easy to adjust and manganese can be codeposited at less than 0.05 mass% in nickel metal electrodeposited with a sulfur content exceeding 0.01 to 0.02 mass%, and the hardness is moderate. As a result, the mechanical strength is increased, and a durable nickel belt that hardly undergoes plastic deformation can be obtained.

  Further, according to the heat-fixing belt of the present invention, sulfur embrittlement is suppressed by the inclusion of manganese even when the fluororesin release layer is baked at 340 to 350 ° C. for 30 minutes, and the strength of the crystal orientation plane is increased. Since the substrate having a ratio [I (200) / I (111)] of 0.4 to 0.5 is used, it is used for heat-fixing with printing durability in which cracks resulting from metal fatigue are suppressed. It can be a belt.

  Furthermore, according to the image forming apparatus of the present invention, since the fixing unit incorporating the heat fixing belt is provided, even if it is repeatedly used at a temperature of 160 to 200 ° C. in the heat fixing process, it does not break. Moreover, despite the high-temperature firing of the fluororesin release layer when forming the fixing belt, sulfur brittleness is suppressed, and an image forming apparatus having printing durability can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a configuration diagram of an electrophotographic image forming apparatus in which a heat fixing belt using an electroformed cylindrical nickel belt as a base is used as a component of a heat fixing unit.

  The toner image forming unit A includes the respective color toner image forming units Y in the order of red, blue, yellow, and black toner. Each color toner image forming unit includes a photosensitive drum 1, a charging unit 2, a developing unit 4, a cleaning unit 6, and the like, and the optical writing unit 3 and the transfer unit 5 are shared. The toner images formed on the photosensitive drums 1 are superimposed on the recording paper 8 conveyed on the transfer belt 7 constituting the transfer unit 5. The recording paper 8 onto which the toner image has been transferred is conveyed to the heat fixing unit 9 and is heat fixed.

  The heat fixing unit 9 is in contact with a fixing belt 11 in contact with a fixing belt 11 which is endlessly stretched between a fixing roller 12 and a heating tension roller 13, a heating pressure roller 10 using a halogen heater inside the roller, and a fixing belt. A cleaning roller 14 for cleaning the fixing temperature, a thermistor 15 for adjusting the fixing temperature, and a thermistor 16 for adjusting the temperature of the heating and pressing roller 10.

  The fixing belt 11 includes a base body 17 made of a cylindrical nickel belt formed by an electroforming method, a silicone rubber layer 18 that is coated on the outer surface of the base body 17 and has good adhesion to the nickel base body 17, and the silicone rubber layer 18. And a fluororesin layer 19 having good releasability from the toner.

  In the heat fixing unit 9, the toner image is transferred at a normal temperature of 160 to 180 ° C. with the recording paper 8 onto which the toner image is transferred being sandwiched between the nip portion 20 constituted by the heat and pressure roller 10 and the fixing belt 11. Fix by heat and pressure. Further, when the temperature of the image forming apparatus is raised, it becomes a severe condition against heat that reaches 200 ° C. This image forming cycle is usually performed 40 to 50,000 times on A4-size recording paper, and the members constituting each unit are required to have durability associated therewith.

  The electroformed cylindrical nickel belt of the present invention that constitutes the base of the fixing belt 11 meets the above-mentioned durability requirements, and is (200) with respect to the peak intensity on the (111) plane measured by X-ray diffraction. The intensity ratio of the metal crystal orientation plane expressed by the ratio of the peak intensity on the plane is in the range of 0.4 to 0.5, and 0.01 to 0.02 wt% contained in the nickel electrodeposited film It is characterized by containing manganese in excess of the sulfur content and less than 0.05% by weight with respect to sulfur.

  The fixing belt 11 is obtained by baking a silicon resin layer 0.1 to 0.3 mm on an electroformed nickel belt (hereinafter referred to as an electroformed nickel belt) 17 serving as a substrate for 30 minutes at a temperature of 100 to 120 ° C. The PFA fluororesin layer 20 to 30 μm used as the mold layer is manufactured by baking at a temperature of 340 to 350 ° C. for 20 to 30 minutes. The heating during the baking is performed by recrystallization of the nickel electrodeposited film and the electrodeposited film. It affects stress relaxation during formation, thereby reducing hardness and reducing mechanical strength. However, as described above, when manganese is added to the sulfur content 0.01 to 0.02% by mass in the nickel metal in an amount exceeding the sulfur content and less than 0.05% by mass, Decrease in hardness is suppressed and plastic deformation becomes difficult, and a substrate with improved durability can be obtained.

  In general, when a metal crystal structure is measured by X-ray diffraction for a substrate to which manganese is not added, the peak intensity ratio [I (200) / I of the (200) plane to the (111) plane in X-ray diffraction. (111)] is in the range of 0.3 to 0.4, and the (200) plane peak intensity tends to be slightly weak. However, the inclusion of the above-described amount of manganese suppresses the transition of crystals and strengthens the space between the crystals. The hardness of the nickel electrodeposited film increases from Hv450 to 470 to Hv480 to 530, and the film thickness is increased to 30 to 30. By setting the thickness to 40 μm, it is possible to obtain a durable nickel belt substrate that hardly undergoes plastic deformation within a range in which flexibility is maintained.

  Furthermore, sulfur that is co-deposited by turning to a firing temperature of 350 ° C. when forming the fluororesin layer goes around the crystal grain boundary to cause sulfur embrittlement. By adding the above amount of manganese, this sulfur Brittleness can be prevented from occurring.

  In the present invention, the upper limit of the manganese content is less than 0.05% by mass so that the hardness of the nickel metal to be electrodeposited does not become Hv 530 or more, thereby applying excessive tension when the fixing unit is configured. Can be prevented.

  Next, the manufacturing method of the electroformed nickel belt of the present invention containing the above-mentioned manganese amount will be described.

  FIG. 2 shows a manufacturing process for containing manganese when forming the base 17 of the electroformed nickel belt by the electroforming method, and when the base is cut into a member width necessary for the image forming apparatus. The manufacturing process for not generating the crack by the stress concentration from the level | step difference formed in FIG.

  In the electroforming process 22 using the nickel sulfamate solution of FIG. 2, first, as the cylindrical metal matrix 23, in order to maintain the adhesion of the nickel electrodeposited film and to prevent pinhole defects and the like of the deposited film, SUS304TB Using a pipe (stainless steel pipe for boiler / heat exchanger) (JIS G 3463 establishment 1994), the outer surface roughness of the nickel electrodeposition surface is formed to Rz 0.03 to 0.1 μm.

  According to the SUS304TB pipe, the occurrence of hole contact on the material surface of the cylindrical metal matrix is low, and the durability of the cylindrical metal matrix can be maintained. Further, by setting the surface roughness (Rz 0.03 to 0.1 μm), the roughness is transferred to the surface of the electrodeposited cylindrical nickel belt substrate, and the number of printing durability sheets is 50,000 or more as a fixing belt. Even if this rotational drive is performed, it is possible to prevent the occurrence of cracks due to the roughness of the substrate surface.

  Next, a ring-shaped auxiliary electrode 24 having a width of 10 to 15 mm is applied to the inner metal of the cylindrical metal base body 27 using a resin insulating material 25 and an insulating material 26 at the lower end of the cylindrical metal base body 27. The upper part of the cylindrical metal mold main body 27 is detachably attached to the carrier 28 and conveyed to the standby position 29.

  After transporting to the standby position 29, the electrodeposited film is electrodeposited on the surface of the cylindrical metal mold main body 27 by the polishing cloth 30 of the abrasive mesh 1800 to 2400 in the polishing step A without peeling during electrolysis. Then, the surface is polished and cleaned so as to keep a mirror surface of 0.1 μm or less.

  Next, in the cleaning step B, the polishing residue on the activated surface is washed with heated pure water and a sponge 31 to prevent the formation of protrusions on the surface of the electrodeposited film, and the activated surface of the cylindrical metal matrix body 27 is maintained. The surface is heated to 40 ° C., which is difficult to dry during transportation.

  Next, in electroforming step C, boric acid 30 to 40 g / l in a solution of nickel sulfamate 450 to 550 g / l, nickel bromide 1 to 2 g / l as an anodic solubilizer, brightener and compressive stress adjuster for the deposited film Saccharin 20 to 100 ppm, sodium naphthalene trisulphonate 500 to 1500 ppm was added, and alkylbenzene sulfonate 0.1 to 0.2 g / l was added as a surfactant to prevent defects such as pits at 55 to 60 ° C. In order to contain manganese in the nickel electrodeposited film, 0.05 to 0.2 g / l of manganese sulfamate is further added. Of these, nickel bromide, saccharin, and alkylbenzene sulfonate are additives and are not essential.

  According to this electrolytic solution, the second brightener that easily adjusts the peak intensity ratio [I (200) / I (111)] of the crystal orientation plane to a range of 0.4 to 0.5 and forms a layered structure. It is not necessary to set the electrodeposition current as low as the electrolytic solution to which is added, and the film can be formed efficiently. In addition, in the above composition, if the manganese sulfamate is adjusted and added in the range of 0.05 to 0.2 g / l, it is nickel that is electrodeposited with a sulfur content exceeding 0.01 to 0.02% by mass. Manganese can be co-deposited in the metal at less than 0.05% by mass, the hardness can be increased moderately, the mechanical strength can be increased, and a durable nickel belt that hardly undergoes plastic deformation can be obtained.

  Consumed manganese ions are supplied from the stock tank 32 to the circulation filtration tank 34 by the metering pump 33 in accordance with the number of production of the liquid added with 5 to 10 g / l of manganese sulfamate. The liquid stirred in the circulation filtration tank 34 is overflowed and supplied from the heating tank 35 into the cathode case 37 of the electroforming tank 36.

  In the electrolysis with this liquid, the metal ion concentration on the cathode surface of the cylindrical metal matrix body 27 is maintained, so that the air stirring effect of the electrolytic solution is enhanced, and protrusions and pits are generated on the surface of the electrodeposited film from foreign substances in the electrolytic solution. The ion-permeable diaphragm 38 is used to prevent the rotation of the cylindrical metal matrix 23 at the center at 6 to 10 rpm, and the peak of the (200) plane crystal orientation plane with respect to the (111) plane in X-ray diffraction. A film thickness of 35 ± 5 μm is formed by setting an electrodeposition current density at which the intensity ratio [I (200) / I (111)] is in the range of 0.4 to 0.5.

  The electrodeposition current density is such that the peak intensity ratio of the crystal orientation plane is in the range of 0.4 to 0.5, and the peak intensity ratio increases as the electrodeposition current density increases. Electrodeposition is performed at a rate of 7 A / dm 2 or less with a low occurrence rate.

  The cylindrical metal base body 27 and the ring-shaped auxiliary electrode 24 are connected to a power source 41 through a current-carrying shaft 39 and a sliding electrode 40, and the titanium case 42 and the titanium case 43 in the electrolytic solution are connected to the anode of the power source 41. Connected and electrodeposition current is supplied.

  The replenishment of nickel ions by repeated electroforming includes a titanium case 42 serving as an anode in which 7 to 10 mm soluble active nickel pellets containing 0.01 to 0.03% sulfur are coated with slime-containing diaphragms 44 and 45, An electric current having a desired electrolysis current density is supplied into the titanium case 43 and supplied to the cylindrical metal base body 27 serving as the cathode and the titanium cases 42 and 43 with an inter-electrode distance 46 and 47 of 100 to 120 mm. .

According to this inter-electrode distance, the above-mentioned crystal orientation plane strength ratio [I (200) / I (111)] is in the range of 0.4 to 0.5, the hardness is in the range of Hv480 to 530, and An electrodeposited film having a compressive stress of 0 to −50 N / mm ² can be formed, and a strong current concentration is caused at the lower edge of the cylindrical metal matrix to cause an electrodeposition stress. Electrodeposition that can be easily peeled without making the deposited film difficult to peel can be performed.

  The active nickel pellets in the titanium case that becomes the anode are dissolved without forming a film by bromine ions of the anodic dissolving agent, the nickel ions are dissolved and supplied together with the supply of the electrolytic current, and the number of times nickel ions are replenished with nickel sulfamate is increased. The amount of metal ions in the electrolytic solution can be stabilized, the maintenance and management of the liquid composition is facilitated, and the production can be continued.

  In the cleaning process D after electroforming, the electrolytic solution adhering to the electrodeposited film of the cylindrical metal matrix 23 is washed and removed, and the electrolytic solution is removed and washed to a nearly complete state by showering with the cleaning solution when it is pulled up. The pure water in the drying process E of the process is not contaminated.

  In the drying step E, the electrodeposited film formed on the surface of the cylindrical metal mold main body 27 is heated to 60 to 70 ° C. for pure water cleaning and drying, and the cleaning water is turned off with an air knife or the like at the time of lifting. Promotes drying and forms a surface free of spots or the like.

  In the mold release process F, a mold release tool 48 is attached and clamped to the outer diameter surfaces of both ends of the electrodeposited film having a film thickness distribution of 3 μm and deposited on the cylindrical metal mold main body 27 to obtain a cylindrical shape. Silicone rubber is used as a masking material for the film thickness increasing portion 49 of the electrodeposited film having a width of 20 to 30 mm formed on both ends of the metal matrix body 27 and the film pressure increasing portion 24 of the electrodeposited film formed on the lower end auxiliary electrode. Adhesive tape is applied to the end of the film thickness increasing portion and the masking portion, and peeled off from the pointed peeling start portion 50 in the direction of the circumferential arrow, while rotating the cylindrical metal matrix 23 Cut off the entire circumference.

When the nickel electrodeposited film is peeled off from the surface of the cylindrical metal matrix, if the electrodeposition stress of the electrodeposited film is peeled off by applying a compressive stress in the range of 0 to -50 N / mm ² , the diameter of the electrodeposited film is reduced. The electrodeposited film can be peeled off from the cylindrical matrix surface by blowing compressed air without touching the surface of the electrodeposited film. In addition, the electrodeposition current that tends to concentrate at the lower end in order to deposit the cylindrical metal matrix vertically is used to prevent an excessive increase in film thickness at the cylindrical metal matrix body by using the auxiliary electrode. (The electrodeposition current is made uniform at the top and bottom), and a nickel belt having a more uniform film thickness can be obtained at the top and bottom of the cylindrical metal matrix body.

  Next, the mold release tool 48 is opened, and the high pressure air is blown between the cylindrical metal mold main body 27 and the electrodeposited film at both ends, and the electrodeposited film is gradually peeled off to completely remove the entire film. The mold is released, and is naturally dropped onto the cushion sponge 52 of the receiving jig 51 and taken out.

  If a cylindrical nickel belt substrate is manufactured by the above-described processes, it can be manufactured with high productivity without causing a minute bend such as a kink that causes a problem such as cracks in the substrate. A substrate with the following characteristics can be obtained.

  Next, the electrodeposited film 53 dropped and taken out by the receiving jig 51 disposed below is processed into a predetermined image forming member width through a cutting step 54 for cutting to a width necessary for the image forming apparatus. Is done.

  In the cutting step 54, a super hard cutting metal roller facing vertically is used, the formed cylindrical nickel belt base 53 is inserted into the lower roller 55, and the waiting upper roller 56 is put on the base. Then, the entire periphery of the base 53 is cut while rotating both ends of the opposing roller blades with a shear clearance of 5 μm, and the cut end portion 57 is formed with a step of 0 to 0.05 mm. .

  If this cut end portion 57 is used with a step of 0.1 mm or more, it will be subject to stress concentration at the step portion due to repeated bending load, causing metal fatigue and becoming a starting point of cracking and easy to break. Reduce durability.

  The cylindrical nickel belt substrate 58 that has undergone the cutting step 54 with the roller blade described above is different from the substrate that is cut by using a laser or the like, so that the cut surfaces at both ends do not become high temperature at the time of cutting without reducing the durability. Can be completed.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.
(Examples 1 to 5)
Using the electroforming process of FIG. 2, the electroforming liquid composition is 450 to 550 g / l nickel sulfamate, 30 to 40 g / l boric acid, 1 to 2 g / l nickel bromide as the anolyte, the primary brightener and the deposited film Nickel was added to an electrolytic solution at 55 to 60 ° C. to which 20 to 100 ppm of saccharin as a compressive stress adjusting agent, 500 to 1500 ppm of sodium naphthalene sulfonate and 0.1 to 0.2 g / l of a surfactant: alkylbenzene sulfonate were added. In order to contain manganese in the electrodeposited film, 0.05 to 0.2 g / l of manganese sulfamate was further added. Consumed manganese ions were supplied from the stock tank 32 to the circulation filtration tank by the metering pump 33 in accordance with the number of productions of 5 to 10 g / l manganese sulfamate.

When replenishing nickel ions, 7 to 10 mm soluble active nickel pellets containing 0.01 to 0.03% sulfur were added to a titanium case covered with a slime-containing diaphragm to promote dissolution, and the pH was adjusted as the electrolyte. It is controlled stably in the range of 4 to 5, the electrolytic current density of the sample is set to 4, 5, 6, 7, 8 A / dm ² , and the cylindrical metal matrix rotating at 6 to 10 rpm and the distance between the poles of 100 to A current was supplied between the anodes of 120 mm to obtain each substrate of a cylindrical nickel belt having a film thickness of 30 to 40 μm (each substrate of Examples 1 to 5).

The (200) plane peak intensity in the X-ray diffraction of the surface of the cylindrical nickel belt formed using the electrolytic solution having the above composition is increased as the electrolytic current density is increased, and the crystal orientation plane strength is increased. The ratio [I (200) / I (111)] is in the range of 0.34 to 0.51, but when the electrolysis current density is greater than 7 A / dm ² , 2 to 5 μm microprotrusions are formed on the surface of the electrodeposited film. Since it is thought that many are formed and become the starting point of cracks, the electrolysis current density is set to a range of 5 to 7 A / dm ² .

  FIG. 3 shows a cylindrical nickel belt substrate 60 formed after a heat treatment unit 59 having the same layout as that of the heat fixing unit 9 of the image forming apparatus is subjected to heat treatment at 350 ° C. for 30 minutes in the fluororesin coating process. And applying a pressing force of 100 to 150 N by a silicone rubber-coated fixing roller 61 with an outer diameter of 25 mm, a heating tension roller 62 with a silicone rubber coating with an outer diameter of 25 mm, and a heating and pressing roller 63 with a silicone rubber coating with an outer diameter of 30 mm. The temperature of the cylindrical nickel belt 60 is detected by the thermistor 65 by the 600 W halogen heater 64 of the heating tension roller 62 covered with silicone rubber, and the temperature is adjusted to 160 to 180 ° C. The surface temperature of the heating and pressure roller 63 is adjusted. Inspection using thermistor 67 by 400W halogen heater 66 Was heated adjusted to 100 to 120 ° C., a cylindrical nickel belt base 60, at a linear velocity of 100 mm / sec, it was rotated equivalent 50,000 sheets A4 printing sheets (i.e., rotated only belt).

Rotational drive equivalent to 50,000 A4 printing plates, no cracks are generated from the steps on both ends of the substrate, and the sulfur content (0.01 to 0.02% by mass) eutectoid in nickel metal is exceeded. It contains less than 0.05% by weight, has a hardness of 480 to 530, a film thickness of 30 to 40 μm, an electrodeposition stress of 0 to −50 N / mm ² , and an electrolytic current density of 4, 5, 6, 7 A / dm. ^No streak-like crack 69 occurs in the image forming width 68 even if the number of printed sheets equivalent to 55,000 sheets is exceeded from each substrate formed in ² and satisfies the function as a substrate for heat fixing. It became.
(Comparative Example 1)
Except for not adding manganese sulfamate in the electroforming liquid composition, the same conditions as in the above example were used, and a current with an electrolytic current density of 5 A / dm ² was supplied to obtain a cylindrical nickel belt substrate.

  In the same manner as in the above embodiment, when a durability test was performed, no cracks were generated from the steps on both ends. However, a streak-like crack 69 was formed in the image forming width 68 with a printing durability equivalent to 52,000 sheets. As a result, the durability was lower than that of the manganese-containing substrate of the example.

  Table 1 shows the production conditions of the cylindrical nickel belt substrates of Examples and Comparative Examples, the strength ratio of the crystal orientation planes of the obtained cylindrical nickel belt substrates, the durability test results, and the like.

  The intensity ratio of the crystal orientation plane was measured under the following conditions using an X-ray diffractometer (Phillips XPPerPRO).

  Conditions: X-ray generator: Cu (encapsulated tube), Filter: None, Sampling width: 0.02, Monochromator (receiving side), Scan rate: 0.5 ° / S, Tube voltage: 40 KV, Diverging slit: 0 0.5 °, tube current: 40 mA, scattering slit: 0.5 °, scan axis: 2θ / θ, receiving slit: variable program, measurement angle range: 30 ° to 90 °, detector: pc.

（注）硫黄含有量は比較例１及び実施例１乃至５のサンプルとも０．０１乃至０．０２質量％の範囲である。

(Note) The sulfur content is in the range of 0.01 to 0.02 mass% for the samples of Comparative Example 1 and Examples 1 to 5.

1 is a side view showing a configuration of an image forming apparatus using a heat-fixing belt having an electroformed cylindrical nickel belt as a base. It is a side view which shows the manufacturing process of the cylindrical nickel belt base | substrate made from electrocasting, and a perspective view which shows the process of cut | disconnecting this base | substrate to the member width required for an image forming apparatus. FIG. 4 is a side view showing a configuration of an endurance tester having the same configuration as a heat fixing unit having an electroformed cylindrical nickel belt as a base, and a perspective view showing a heat fixing belt in which a crack has occurred in the image forming width.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoconductor unit 4 Developing unit 5 Fixing unit 9 Heating fixing unit 10 Heating and pressing roller 11 Fixing belt 12 Fixing roller 13 Heating tension roller 17 Cylindrical nickel belt substrate 18 Silicone rubber layer 19 Fluoro resin layer 22 Electroforming process 23 Cylinder Metal mold 24 Auxiliary electrode 25, 26 Insulating material 27 Cylindrical metal mold body 30 Polishing cloth 31 Sponge 32 Stock tank 33 Metering pump 34 Circulation filtration tank 35 Heating tank 36 Electroforming tank 42, 43 Titanium cases 46, 47 Electrode distance 48 Mold release tool 49 Thickness increasing part 50 Peeling start part 51 Receiving jig 53 Electrodeposited film (cylindrical nickel belt substrate)
54 Cutting Process 55 Lower Roller 56 Upper Roller 57 End of Cutting

Claims (10)

  An electrocast cylindrical nickel belt having a strength ratio of the metal crystal orientation plane represented by a ratio of the peak intensity at the (200) plane to the peak intensity at the (111) plane measured by X-ray diffraction [I ( 200) / I (111)] is in the range of 0.4 to 0.5, and the content of manganese with respect to 0.01 to 0.02% by mass of sulfur contained in the nickel electrodeposition film The cylindrical nickel belt made of electrocasting, wherein the content exceeds the above-mentioned content of sulfur and is less than 0.05% by mass. In the electroforming method of forming an electrodeposited nickel film on the surface of a cylindrical metal matrix using an electrolytic solution containing nickel sulfamate, the electrolytic solution comprises at least the following compositions 1 to 4. Item 2. A method for producing an electroformed cylindrical nickel belt according to Item 1.
1 Nickel sulfamate 450 to 550 g / l
2 Boric acid 30-40g / l
3 Naphthalene sodium lisulfonate 500 to 1500ppm
4 Manganese sulfamate 0.05 to 0.2 g / l The method for producing an electroformed cylindrical nickel belt according to claim ² , wherein electrodeposition is performed at a current density of 5 to 7 A / dm2.   3. The method for producing an electroformed cylindrical nickel belt according to claim 2, wherein the cylindrical metal matrix is mirror-finished with a surface roughness Rz of 0.03 to 0.1 [mu] m.   The method for producing an electroformed cylindrical nickel belt according to claim 2, wherein a seamless pipe of SUS304TB pipe (JIS G 3463 established 1994) is used as the cylindrical metal matrix.   The electrocasting according to claim 2, wherein electrodeposition is carried out by setting a distance between electrodes of a cylindrical metal matrix having an auxiliary electrode attached to a lower end portion serving as a cathode and a titanium anode plate serving as an anode to 100 to 120 mm. A method for producing a cylindrical nickel belt. When the nickel electrodeposition film formed on the surface of the cylindrical metal matrix is peeled off, the electrodeposition stress of the electrodeposition film is peeled off by applying a compressive stress in the range of 0 to −50 N / mm ^2. A method for producing an electroformed cylindrical nickel belt according to claim 2.   The both ends of the electroformed cylindrical nickel belt according to claim 1 or the electroformed cylindrical nickel belt manufactured by the manufacturing method according to any one of claims 2 to 7 are opposed to the cylindrical nickel belt. A belt base for heat-fixing, characterized in that the cutting step is 0 to 0.05 mm by cutting with a roller blade.   9. A heat-fixing belt, wherein a silicone rubber layer and a fluororesin release layer are formed on the surface of the substrate according to claim 8.   An electrophotographic apparatus comprising a heat fixing unit incorporating the heat fixing belt according to claim 9.

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