JP2007253347A - Joining member manufacturing method, endless joining belt, fixing unit, intermediate transfer unit, image forming device, and sheet joining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a joining member manufacturing method which prevents the occurrence of thickness spots in a lamination part even when a wide sheet is laminated in spit of being simple in structure and develops high adhesive strength. <P>SOLUTION: In the joining member manufacturing method for obtaining a joining member by bonding different end parts of one sheet or the end parts of different sheets to each other, when an end part coated with a heat-curable adhesive, after being laminated with another end part, is joined by heating at the curing temperature of the adhesive, the lamination part, after being held between a first fixing member made of a magnetized body from one surface of the lamination part and a second fixing member made of a magnetized body or a magnetic body arranged on the other surface, is heated at the curing temperature of the adhesive. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a full-color copying machine for transferring a full-color image onto a transfer material after a toner image is superimposed on an intermediate transfer member to form a full-color image, and a transfer belt or a fixing belt used for thermal fixing of a transfer body of a printer. The present invention relates to a joining member manufacturing method applicable to the production of an endless joining belt used, and an endless joining belt, a fixing unit, an intermediate transfer unit, an image forming apparatus, and a sheet joining apparatus obtained by the joining member manufacturing method.

  In an image forming apparatus such as a copying machine or a printer, when obtaining a full color image, a toner image of each color is formed on a photoconductor, and sequentially transferred onto a belt as an intermediate transfer member, and then a multicolor image is formed on the intermediate transfer belt. Then, the image is electrostatically transferred again onto the transfer material and a multicolor image without image displacement is formed. It is also known to heat and fix the toner placed on the transfer paper in this way.

  Recently, with respect to members used for such transfer and thermal fixing, flexible belts are often used because of the freedom of layout.

  In such a belt, a seamless endless belt (seamless belt) is often used in order to avoid synchronization control or the like when the apparatus is driven.

  These flexible belts are required to have flame retardancy, mechanical strength, and electrical stability, and polyimide resin is used. In particular, in the case of a fixing belt, a polyimide resin is used from the viewpoint of heat resistance.

  In the formation of these endless belts (seamless belts), conventionally, a coating solution is applied to the inside or the outside of a coating mold, the solvent is dried, and then the resin component is cured.

  Here, there are various methods such as dipping, spray coating, centrifugal molding, etc. for the manufacturing method of such an endless belt, but the centrifugal molding method is superior from the standpoints of good material use efficiency and exhaust gas recovery. Yes. However, in this method, if the solvent is not removed to a predetermined amount, the coating film is fluidly deformed, and a coating mold must be prepared for each one. Therefore, the productivity is very low.

  For this reason, an endless joining belt has been used in practice. A method for obtaining a seamless belt by cutting a sheet or film that can be continuously produced in large quantities and winding it around a core is disclosed in Japanese Patent Application Publication No. WO 00/069623 (Patent Document 1), “Multilayer Endless Belt, Medium Conveying Belt Consisting of the Same, and These manufacturing methods and forming apparatuses "are proposed.

  Specifically, this technique is a multi-layer endless belt having a structure formed by winding and constituting a laminated body, and has a structure in which a so-called Baumkuchen type non-thermoplastic polyimide is wrapped with a thermoplastic resin and heat-sealed. It is a joining belt. However, the adhesion between the layers in such multi-layer winding increases the resin area as the adhesive layer, and if there is a heating temperature distribution, the adhesion is non-uniform, resulting in a variation in thickness of the laminate.

  Japanese Patent Application Laid-Open No. 2001-290384 (Patent Document 2) proposes an end bonding fusion method. Specifically, it is a method of making the belt seamless by joining by ultrasonic welding or the like, but in this case, since the material of the base material to be joined must be thermoplastic, the belt of a device to which high heat is applied such as a fixing device The application range was narrow because it could not be used due to softening or melting.

  Japanese Patent Laid-Open No. 10-217348 (Patent Document 3) “Belt and its manufacturing method” provides a step by shifting the position of the end of two sheets, and bonds the ends together. A bonding method has been proposed. However, even in this method, it is difficult to sufficiently and uniformly perform bonding and bonding, and unevenness is likely to occur, resulting in variations in the film thickness of the bonded portion.

  Furthermore, in Japanese Patent Laid-Open No. 10-000698 (Patent Document 4), a rugged saddle-shaped structure is formed at the end of bonding, and a strong bonding film is formed by fitting, but with such a complicated shape, When trying to improve accuracy, the cutting and grinding conditions are very severe, and there is a problem that the production efficiency does not increase.

  However, joining non-thermoplastic resin sheets has the following problems with simple shapes, stepped shapes, and obliquely tapered shapes.

  That is, since the resin film itself cannot be bonded by heat, an adhesive must be used. Recently, however, good chemical and chemical-resistant polyimide resins have been developed with good silicone and epoxy adhesives, and surface treatment such as UV treatment and corona discharge treatment can improve adhesion. It is coming.

  However, even if the adhesive is not used, if the pressing of the bonded portion during bonding is not uniform, deflection occurs in the area where the pressing is loose. In particular, when manufacturing an endless joining belt, the smaller the diameter is, and the stronger the sheet used is, the more easily a problem occurs in the formation of the joining portion.

  For workpieces that are long in the axial direction, such as a fixing belt with a bonding width of several millimeters and a bonding area of 30 cm or more, even when pressed with metal or the like and evenly pressed at the beginning of heating, Swelling causes distortion in the holding strength.

However, if both ends of the pressing member are fixed, the pressing member expands, so that the vicinity of the center becomes an arc shape and the circumferential length becomes long, so that uniform bonding cannot be achieved. In particular, when applied to the manufacture of an endless belt, a drum-shaped (barrel-shaped) circumferential difference occurs, and such an endless belt has a short life. Furthermore, when applied to an image forming apparatus, wrinkles are generated on the conveyed sheet or image distortion is caused.
Special publication WO00 / 066963 JP 2001-290384 A JP 10-217348 A JP-A-10-000698

  In order to solve the above-mentioned problem, the present invention has a simple structure, and even when a wide sheet is bonded, there is no unevenness in the thickness of the bonded portion, and a bonded member that exhibits high adhesive strength is produced. It is an object to provide a method.

  In order to solve the above-described problem, the bonding member manufacturing method of the present invention is a bonding method in which different end portions of one sheet or end portions of different sheets are bonded to obtain a bonding member as described in claim 1. In the member manufacturing method, after the other end portion is bonded to the end portion to which the thermosetting adhesive is applied, the bonded portion is heated at the curing temperature of the thermosetting adhesive and bonded. Is sandwiched between a first fixing member made of a magnetized body arranged on one surface of the bonded portion and a second fixing member made of a magnetized body or magnetic material arranged on the other surface, It is a joining member manufacturing method characterized by heating to the curing temperature of the thermosetting adhesive.

  Moreover, the joining member manufacturing method of this invention is the joining member manufacturing method of Claim 1 as described in Claim 2, and Curie point temperature Tq1 of the magnetization body of the said 1st fixing member, and said 2nd Both the magnetized body of the fixing member or the Curie point temperature Tq2 of the magnetic body are higher than the curing temperature T1 of the thermosetting adhesive, and the Curie point temperature Tq1 of the magnetized body of the first fixing member is the second fixed temperature. After heating the member's magnetized body or the Curie point temperature Tq2 of the magnetic body to the curing temperature T1 of the thermosetting adhesive to join the bonded portion, the temperature of the second fixing member is increased. While the temperature is lower than Tq1 and higher than the temperature Tq2, the holding of the bonded bonding member by the first fixing member and the second fixing member is eliminated.

  In order to solve the above-described problem, the bonding member manufacturing method of the present invention is a bonding method in which different end portions of one sheet or end portions of different sheets are bonded to obtain a bonding member as described in claim 3. In the member manufacturing method, after the other end is bonded to the end of the self-heat-adhesive sheet, the bonded portion is bonded to the bonding portion when heated to the bonding temperature of the self-heat-adhesive sheet by heat treatment means. After being sandwiched between a first fixing member made of a magnetized body arranged on one surface of the mating portion and a second fixing member made of a magnetized body or magnetic material arranged on the other surface, the self-heat bonding It is a joining member manufacturing method characterized by heating to the adhesion temperature of an adhesive sheet.

  Moreover, the joining member manufacturing method of this invention is the joining member manufacturing method of Claim 3 as described in Claim 4, and Curie point temperature Tq1 of the magnetized body of the said 1st fixing member, and said 2nd Both the magnetized body of the fixing member or the Curie point temperature Tq2 of the magnetic body is higher than the adhesive temperature T2 of the self-heat-adhesive sheet, and the Curie point temperature Tq1 of the magnetized body of the first fixing member is the second fixed temperature. After the temperature of the magnetic material of the member or the Curie point temperature Tq2 of the magnetic material is higher and the adhesive temperature T2 of the self-heat-adhesive sheet is heated to join the bonded portion, the temperature of the second fixing member is increased. While the temperature is lower than Tq1 and higher than the temperature Tq2, the holding of the bonded bonding member by the first fixing member and the second fixing member is eliminated.

  Moreover, the joining member manufacturing method of this invention is the joining member manufacturing method of any one of Claim 1 thru | or 4 as described in Claim 5, The sheet | seat member in which the said sheet | seat disperse | distributed magnetic powder. It is characterized by comprising.

  Moreover, the joining member manufacturing method of this invention is the joining member manufacturing method of Claim 5 as described in Claim 6, The said heat processing apparatus is an electromagnetic induction type heat processing apparatus, It is characterized by the above-mentioned.

  Moreover, the joining member manufacturing method of this invention is the joining member manufacturing method of any one of Claim 1 thru | or 6 in Claim 7 at the hardening temperature of the said thermosetting type adhesive agent, as described in Claim 7. The heating is performed in such a manner that a weight due to one mass of the fixing member is applied to the bonded portion.

  Moreover, the joining member manufacturing method of this invention is the joining member manufacturing method of any one of Claim 1 thru | or 7 as described in Claim 8, wherein the said fixing member has flexibility. It is characterized by being.

  Moreover, the endless joining belt of this invention was produced by the joining member manufacturing method of any one of the said Claim 1 thru | or 9 as described in Claim 9, The endless form characterized by the above-mentioned. It is a joining belt.

  According to a tenth aspect of the present invention, there is provided a fixing unit using the endless joining belt according to the ninth aspect.

  An intermediate transfer unit according to the present invention is an intermediate transfer unit using the endless joining belt according to claim 9 as described in claim 11.

  According to a twelfth aspect of the present invention, the image forming apparatus includes the fixing unit using the endless joining belt according to the ninth aspect and / or the intermediate transfer unit. An image forming apparatus.

  In addition, the sheet bonding apparatus according to claim 13 is a sheet bonding apparatus in which two overlapped sheet end portions are bonded together by heat bonding, and the first fixing made of a magnetized body for sandwiching the bonded portions. A sheet joining apparatus including a member and a second fixing member made of a magnetized body or a magnetic body.

  According to the method for manufacturing a joining member of the present invention, it is possible to perform uniform pressing even when a wide sheet is bonded while having a simple configuration, and thus there is no unevenness in the thickness of the bonded portion, and High adhesive strength can be obtained.

  According to the joining member manufacturing method of Claim 2 and Claim 4, after heating to joining temperature and hardening a thermosetting adhesive, a 2nd fixing member is lower than temperature Tq1, and temperature By heating at a temperature higher than Tq2, pinching of the joined joint member by the first fixing member and the second fixing member is eliminated. At this time, the magnetism of the second fixing member is lost, the adsorption (adhesion) force due to the magnetic force with the first fixing member is lost, and the fixing force for fixing the joining member that is the product is released. It is very easy to eliminate the sandwiching of the joined joint member by the securing member and the second securing member, and it becomes easy to take out and remove the joined joint member, which is the product, from the heating means. Since no cooling time is required, the removal operation can be performed quickly, easily and safely, and the productivity is improved.

  According to the method for manufacturing a joining member according to claim 5, since the sheet is made of a sheet member in which magnetic powder is dispersed, the sheet itself has magnetic permeability, so that it is attracted (attached) to the magnetized body. It can be fixed by the fixing member more effectively. Furthermore, since the electric resistance is lowered with a magnetic material, the belt can have antistatic properties. Therefore, if such a joining member manufacturing method is applied to the manufacture of a fixing belt, such a fixing belt is mounted. Problems such as electrostatic offset of the fixed fixing unit can be prevented in advance.

  According to the method for manufacturing the joining member according to the sixth aspect, it is efficient because only a necessary portion can be heated.

  According to the method for manufacturing a joining member according to claim 7, the heating is performed so that the bonded portion receives one mass of the fixing member, and at this time, the upper fixing member also functions as a weight. Therefore, the bonded portion can be easily and effectively fixed. Here, it is possible to maximize this effect by performing the heat treatment so that the bonding portion and the vicinity thereof are horizontal, or the bonding portion is positioned on the uppermost portion of the curved surface formed by the sheet. Can do.

  According to the joining member manufacturing method according to claim 8, since the fixing member has flexibility, the adhesion with the bonded portion is improved, and the dimensional deviation at the time of the heat treatment is reduced, and the joined portion is reduced. The thickness unevenness is reduced, and higher adhesive strength is obtained.

  Furthermore, by being flexible, a good fixing effect can be obtained even if the shape of the bonded portion during heating is not flat.

  Since the endless joining belt of the present invention is manufactured by the above-described method, there is no thickness unevenness, the adhesive strength of the joining portion is high, and the circumference seen in the drum shape (pincushion shape), drum shape (barrel shape), and the like. It is a high-quality endless joining belt with little long deviation and a long life.

  Since the fixing unit and the intermediate transfer unit of the present invention use the endless joining belt as described above, high-quality fixing and transfer are possible.

  Since the image forming apparatus of the present invention is equipped with the fixing unit and / or the intermediate transfer unit as described above, high-quality image formation is possible.

  In general, a thin material is referred to as a film, and a thick material is referred to as a sheet. In the present invention, these are collectively referred to as a sheet. The sheet material used in the present invention can be appropriately selected according to the application.

  In the present invention, if what is bonded to the sheet edge is the edge of another sheet, a joining member formed by bonding two sheets can be formed, but if different edges of one sheet are bonded, a roll shape A belt-like joining member is formed.

The adhesive used in the present invention needs to be a thermosetting type. In addition, it is natural that the curing temperature is lower than the substantial heat resistance temperature of the sheet to be used.
Epoxy resin-based thermosetting adhesives generally have a curing temperature of about 60 ° C to 100 ° C, and silicone-based thermosetting adhesives generally have a curing temperature of about 100 ° C to 200 ° C. Available.

  If a self-heat-adhesive sheet is used as the sheet, an adhesive can be dispensed with. Examples of such a sheet include a polyimide sheet having self-adhesiveness (self-holding property) before imidization is completely completed. Such a sheet is bonded, fixed with a fixing member, and then heated to form an imide. If the process is completed, bonding is completed at the same time.

  These sheets are preferably made of a sheet member in which magnetic powder is dispersed. According to such a configuration, since the sheet itself has magnetic permeability, it can be more effectively fixed by the fixing member by being attracted (attached) to the magnetized body. Furthermore, since the electric resistance is lowered with a magnetic material, the belt can have antistatic properties. Therefore, if such a joining member manufacturing method is applied to the manufacture of a fixing belt, such a fixing belt is mounted. Problems such as electrostatic offset of the fixed fixing unit can be prevented in advance.

  Here, magnetized bodies (magnets) having various Curie point temperatures are commercially available, and as a magnetic body, for example, in a nickel-iron-based alloy, the composition ratio is changed to a range of less than −100 ° C. to more than 400 ° C. It is known that a product having a predetermined Curie point temperature can be obtained.

  Among these, it is necessary to select and use a magnetic body or a magnetized body for the fixing member used in the present invention that does not lose magnetism at the heating temperature for the above bonding.

  One of the two fixing members to be used needs to be made of a magnetic body, but one of them may be made of a magnetic body or a magnetic body. However, if both are magnetized bodies, they must be used in consideration of their polarities, but if the other is made of a magnetic body, it is preferable because such considerations are unnecessary.

  The shape and size of the bonded portion are determined as necessary. For example, in the case of manufacturing a belt, a step is provided on the end portion to be bonded so as not to cause a partial thickness difference (see FIG. 1A. Reference numeral 1 in the drawing is a sheet, and 2 is an adhesive. Or a tapered portion (see FIG. 2 (a). In the figure, reference numeral 1 is a sheet, 2 is an adhesive), and the bonding area is increased to obtain a sufficient bonding strength. Is processed in advance so as not to cause thick spots.

  In order to obtain a sufficiently high effect, the fixing by the fixing member to be used is usually performed on an area which is the same as or larger than the bonded portion, that is, the fixed portion may be fixed so as to cover the entire bonded portion. desirable.

  The fixing members are arranged on both sides of the bonding portion (see FIGS. 1B and 2B. Reference numeral 3 denotes a first fixing member, and reference numeral 4 denotes a second fixing member (this example). However, as long as the effect of the present invention is obtained, a plurality of fixing members may be used instead of one as long as the effect of the present invention is obtained. It may be used.

  If the bonding process is performed so that the bonded portion receives one mass of the fixing member (the state is shown in FIG. 1C as a model), the upper fixing member (in FIG. 1C) Since the fixing member 3) can function as a weight, the bonded portion can be easily and effectively fixed. Here, it is possible to maximize this effect by performing the heat treatment so that the bonding portion and the vicinity thereof are horizontal, or the bonding portion is positioned on the uppermost portion of the curved surface formed by the sheet. Can do.

  The shapes of the first fixing member and the second fixing member can be appropriately selected according to the shape of the obtained joining member and the shape of the bonded portion. Here, for example, when manufacturing an endless joining belt, as shown in a front view in a model form in FIG. 3A, one of the fixing members is a cylindrical shape having a smaller diameter than the inner diameter of the belt to be manufactured (see FIG. The middle part 1) and the other is a rectangular parallelepiped (symbol 2 in the figure), and the laminated portion of the sheet 1 may be sandwiched (set) between them, or as shown in FIG. The diameter of the cylindrical fixing member may be the same as the inner diameter of the manufactured belt. In these cases, if the rectangular parallelepiped fixing member is flexible, it has a shape along the side surface of the cylindrical fixing member, so that the fixing effect of the bonded portion is improved and the thickness variation in the circumferential direction is improved. And an endless joining belt having a high joining strength can be obtained.

  FIG. 2C shows an example in which the shape of the two fixing members 3 and 4 is a rectangular parallelepiped, and the bonded portion of the sheet 1 is set (sandwiched) between them.

  The bonding member manufacturing method of the present invention is a bonding member manufacturing method in which different end portions of one sheet or different sheet end portions are bonded to obtain a bonding member, and a thermosetting adhesive is applied. After pasting the other end to the end, when joining by heating to the curing temperature of the thermosetting adhesive, the pasted portion is removed from the magnetized body from one surface of the pasted portion. Between the first fixing member and the second fixing member made of a magnetized or magnetic material disposed on the other surface, and then heated to the curing temperature of the thermosetting adhesive, or 1 In the joining member manufacturing method of adhering the ends of different sheets, or the ends of different sheets to obtain a joining member, after bonding the other end to the end of the self-heat-adhesive sheet, It is added to the adhesive temperature of the self-adhesive sheet by heat treatment means. In this case, the bonding portion includes a first fixing member made of a magnetized body arranged on one surface of the bonding portion, and a second member made of a magnetized body or magnetic material arranged on the other surface. After being sandwiched between the fixing members, it is heated to the bonding temperature of the self-heating adhesive sheet.

  After this heat treatment, the holding of the bonded bonding member by the first fixing member and the second fixing member is eliminated, and the bonded bonding member as a product is taken out from the heating means or heated. Remove from the means, or remove the heating means arranged in the vicinity of the joint, but at this time the work is difficult to work because the fixing members are attracting each other, and because the force is required, it remains at a high temperature And dangerous. However, when taking out after cooling, a cooling time is required and productivity becomes low. Here, by selecting the magnetized bodies (magnetic bodies) of the two fixing members to be used according to the curing temperature of the thermosetting adhesive or the adhesive temperature of the self-heat-adhesive sheet, the take-out operation can be easily performed.

  That is, the curing temperature T1 of the thermosetting adhesive used by the magnetized body of the first fixing member Tq1 and the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member (or the self-thermal bonding used). Higher than the adhesive temperature T2) of the conductive sheet, the Curie point temperature Tq1 of the magnetized body of the first fixing member is higher than the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member, and heat After heating to the curing temperature T1 of the curable adhesive (or the adhesive temperature T2 of the self-heat-adhesive sheet) and joining the bonded portion, the second fixing member is lower than the temperature Tq1 and the temperature Tq2 By eliminating the holding of the bonded joint member by the first fixing member and the second fixing member while maintaining a higher temperature (takeout temperature T3), the pinching by these can be eliminated. It becomes easy to take out the bonded joint members as a product from the heating means, or removed from the heating means, or the task of removing the heating means arranged in the vicinity of the junction, quickly, safely, and easily.

  In this case, since the Curie point temperature Tq1 of the magnetized body of the first fixing member is higher than the take-out temperature T3, the magnetized body of the first fixing member can be used repeatedly. Moreover, the second fixing member can be used repeatedly by being made of a magnetic material. Depending on the temperature control accuracy of the heating device, if the Curie point temperature Tq1 of the magnetized body of the first fixing member is selected to be about 20 to 30 ° C. higher than the take-out temperature T3, the temperature change is somewhat large Even so, it is possible to reliably use the magnetized body of the first fixing member.

  Further, the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member is higher by about 10 ° C. or more than the curing temperature of the thermosetting adhesive (or the adhesive temperature of the self-thermoadhesive sheet used) T1. desirable. That is, even when the width of the temperature change at the time of heating at the time of bonding is large to some extent, the fixing by the fixing member by the magnetic force is prevented from becoming invalid. Furthermore, the upper limit of the take-out temperature T3 is equal to or lower than the heat resistance temperature of the sheet (and the adhesive), and is determined within a range that does not adversely affect these.

  In the present invention, heating may be performed on the entire sheet in a heating furnace, or may be performed only on the bonded portion (and the fixing member). In the latter case, an electromagnetic induction heating (IH) method or a fixing member (reference numeral 5 in the figure) having a heater inside may be used as the heating means, as shown in FIG. it can.

  The endless belt obtained by the method for manufacturing the joining member of the present invention is a belt base 6 as shown in FIG. 4, and FIG. 4 (a) (a perspective view of the entire belt) and FIG. As shown in a model in the cross-sectional view in the vicinity, a fixing belt or a transfer belt is formed by sticking a stop tape to prevent lateral displacement at both ends of a laminated belt 9 formed by sequentially laminating an elastic layer 7 and a release layer 8. be able to.

  Such a fixing belt can be incorporated in a fixing device, a transfer belt can be incorporated in an intermediate transfer unit, and further incorporated in an image forming apparatus for use in image formation.

  Hereinafter, the present invention will be described in detail by way of examples.

<Example 1>
A commercially available sheet made of polyimide with a film thickness of 80 μm is first cut into dimensions of width 330 mm × length 230 mm, then punched (bic punch: Thomson type) to a width of 300 mm and a length of 198.50 mm, both ends in the width direction Surfaces different from each other at one end and the other end were ground to 10.0 mm, and 45 μm was scraped off to obtain a processed sheet a having a remaining thickness of 35 μm.

  Similarly, processing is carried out from a commercially available sheet made of polyimide having a film thickness of 80 μm, having a width of 300 mm, a length of 193.50 mm, both ends in the width direction being 5.0 mm, and a step having a grinding part thickness of 35 μm is provided. A finished sheet b was obtained.

  Both the ground surfaces of these sheets a and b have staggered steps as shown in a model in FIG. A silicone-based adhesive 2 (curing temperature: 150 ° C., SE1700 manufactured by Toray Silicone Co., Ltd.) was applied to the overlapping region at both ends of these sheets (reference numeral 1 in the figure) by screen printing.

  Each of these adhesive-coated sheets is a cylindrical fixing member having magnetism as a first fixing member as schematically shown in FIG. 3A (the Curie point Tq2 of the magnetic body is 160 ° C. Note that the magnetic body) The nickel-iron alloy having a different composition suitable for the required Curie temperature was selected and used (hereinafter the same).) 4) Set on the outer surface of 4 so that the overlapping area of the end portion is at the top. Then, the overlapping regions at both ends of the sheet are bonded together, and the magnetized body (magnet) is dispersed from the outside of the cylinder to the uppermost portion of the outer surface of the cylindrical body 1 made of such a sheet, that is, the bonded portion. A flexible sheet having flexibility (Curie point Tq1 of the magnetized body is 260 ° C.) is stacked as a fixing member 3 (second fixing member), and heated at a temperature of 150 ° C. for 20 minutes. Was heated in a (furnace), they were joined by curing a silicone adhesive 2.

  Thereafter, the temperature of the heating furnace was raised so that the temperature of the cylindrical fixing member 4 was 165 ° C., the fixing member 3 was removed, and then the joined sheet, that is, the endless joining belt was removed from the cylindrical fixing member 4. At this time, since the fixing member 3 has lost its magnetism, the removal operation can be performed very easily and quickly.

  When the circumference of the extracted endless joining belt is measured, the accuracy required for the fixing belt regardless of whether the adhesive coating width is 10.0 mm (depending on the sheet a) or 5.0 mm (according to the sheet b) at both ends and the central portion. It was 188.5 mm ± 0.05 mm or less satisfying ± 5/100 mm of the circumference deviation standard, which was good with no difference in circumference.

  Note that the adhesive used above was extremely viscous before heat treatment, and did not shift or float immediately after application and lamination. The alignment part gradually shifted.

<Comparative Example 1>
Processed sheets a and b were prepared in the same manner as described above, and the same silicone adhesive as used in Example 1 was applied to the overlapping regions at both ends by screen printing.

  Wrap these adhesive-coated films around the sides of the cylinder, pin the vicinity of both axial ends of the overlapping area at both ends of the sheet, and from the outside of the cylinder, with a size that completely covers the bonded part. A pressing member having a concave curved surface along the side surface is overlaid on the bonding portion, and is screwed at two positions near both ends in the axial direction of the cylindrical body, so that the bonding portion is pressurized with a pressing pressure of 3N. After fixing, it was heated in a heating furnace at a temperature of 150 ° C. for 20 minutes.

  Then, after taking out from the furnace with the pressing member and cooling, the screw was loosened to release the pressure, the pressing member was removed, and the belt to which the bonded portion was bonded was removed from the cylindrical body.

  After the heat curing treatment, the adhesive application width of 10.0 mm is 188.50 mm at the peripheral length of both ends, 188.58 mm at the central portion, while the adhesive application width of 5 mm is the peripheral length of both ends. The difference in circumference was 188.50 mm at the center and 188.65 mm at the center, both of which did not satisfy the above standards.

<Example 2>
10% by weight of ferrite fine powder was added to a commercially available polyimide varnish (polyamic acid solution) and mixed by stirring to prepare a coating solution. This coating liquid is poured on a glass flat plate to form a smooth surface with a predetermined liquid thickness using a blade, then dried in a heating furnace at a temperature of 120 ° C. to remove the solvent, and then a temperature of 300 ° C. Was used to prepare a sheet having a thickness of 80 μm.

  This sheet was processed in the same manner as in Example 1 and processed to a sheet c having a width of 300 mm, a length of 198.50 mm, both ends 10.0 mm in the width direction being ground, and a step having a thickness of 35 μm was provided. Obtained a processed sheet d having a width of 300 mm and a length of 193.50 mm, and 5.0 mm of both end portions in the width direction were ground to provide a step of 35 μm.

  The same silicone adhesive as that used in Example 1 was applied by screen printing to the overlapping regions at both ends of these processed sheets c and d.

  This adhesive-coated sheet is formed on the outer surface of a cylindrical fixing member 4 having magnetism (the Curie point Tq2 of the magnetic material is 160 ° C.) 4 as schematically shown in FIG. The overlapping area of the sheet is set to be the uppermost part, and the overlapping areas at both ends of the sheet are bonded together, and the uppermost part of the outer surface of the cylindrical body 1 made of such a sheet, that is, the bonding part Then, a flexible (flexible) sheet (a Curie point Tq1 of the magnetized body (magnet) of 260 ° C.) in which the magnetized body (magnet) is dispersed from the outside of the cylinder is overlapped as the fixing member 3, and 150 ° C. It heated in the heating apparatus (heating furnace) for 20 minutes at temperature, the silicone type adhesive agent 2 was hardened, and it joined.

  Thereafter, the temperature of the heating furnace was raised so that the temperature of the cylindrical fixing member 4 was 165 ° C., the fixing member 3 was removed, and then the joined sheet, that is, the endless joining belt was removed from the cylindrical fixing member 4. At this time, since the fixing member 3 has lost its magnetism, the removal operation can be performed very easily and quickly.

  When the circumference of the extracted endless joining belt is measured, the fixing belt, the transfer belt, etc. can be used regardless of whether the adhesive coating width is 10.0 mm (depending on the sheet c) or 5.0 mm (depending on the sheet d). No more than 188.5 mm ± 0.04 mm, which satisfies ± 5/100 mm of the circumference deviation standard, which is the accuracy required for the image forming apparatus of FIG.

<Example 3>
A sheet prepared in the same manner as in Example 2 was cut into a width of 300 mm and a length of 198.50 mm, and both end portions in the width direction were 10.0 mm and different surfaces were ground on one end and the other end. A sheet e having an oblique cross section (taper grinding) with an angle of 18 minutes was obtained. Moreover, it cut | disconnected to width 300mm and length 193.50mm, both ends 5.0mm of the width direction were ground, and the sheet | seat f made into the diagonal-shaped cross section (taper grinding) of the angle of 20 minutes was obtained. In these, both ends left a thickness of 10 to 20 μm in order to prevent curling and twisting. Further, the ground surfaces were alternately turned, and the same silicone adhesive as in Example 1 was applied to the overlapping portions at both ends by screen printing.

  The adhesive-coated sheet was subjected to a 20-minute heat adhesion treatment at a temperature of 150 ° C. and a removal treatment at a temperature of 165 ° C., as in Example 1. The removal operation was as easy as in Example 1. And it was possible to do it quickly.

  When the circumference of the obtained endless joining belt is measured, the fixing belt, the transfer belt, etc., regardless of whether the adhesive coating width is 10.0 mm (based on the sheet e) or 5.0 mm (based on the sheet f) at both ends and the center. No more than 188.5 mm ± 0.04 mm, which satisfies ± 5/100 mm of the circumference deviation standard, which is the accuracy required for the image forming apparatus of FIG.

<Example 4>
Sheets e and f prepared in the same manner as in Examples 4 and 3 were coated with the same silicone adhesive as used in Example 1 by screen printing on the overlapping portions at both ends thereof.
A sticking portion is positioned on the upper surface of the adhesive-coated sheet, with a rectangular parallelepiped block 4 made of a magnetic material (Curie point Tq2 is 160 ° C.) as shown in FIG. In this way, a sheet made of a magnetized body (magnet) (Curie point Tq1 is 260 ° C.) is overlaid as a first fixing member on the bonding portion, the bonding portion is leveled, and the temperature is 150 ° C. For 20 minutes to cure the adhesive.

  Thereafter, the temperature of the heating furnace was raised so that the temperature of the block body 4 ′ was 165 ° C., the fixing member 3 was removed, and then the joined sheet, that is, the endless joining belt was removed from the cylindrical fixing member 4. At this time, since the fixing member 3 has lost its magnetism, the removal operation can be performed very easily and quickly.

  When the circumference of the extracted endless joining belt is measured, the fixing belt, the transfer belt, etc. can be used regardless of whether the adhesive coating width is 10.0 mm (depending on the sheet c) or 5.0 mm (depending on the sheet d). No more than 188.5 mm ± 0.04 mm, which satisfies ± 5/100 mm of the circumference deviation standard, which is the accuracy required for the image forming apparatus of FIG.

<Evaluation as fixing belt>
The joining belts according to Examples 1 to 4 and Comparative Example 1 thus prepared (two kinds with different joining lengths) were used as the bases, and an elastic layer of silicone rubber was formed on each with a thickness of 200 μm. Further, a fluororesin release layer having a thickness of 5 μm was formed thereon to obtain a joining endless belt for fixing.

  The joined endless belt thus obtained is used as a belt base 6, and as shown in FIG. 4A (a perspective view of the entire belt) and FIG. 4B (a sectional view of the vicinity of the joined portion). An elastic layer 7 and a release layer 8 are sequentially laminated to each other, and a fixing tape is attached to both ends of the laminated belt 9 to prevent lateral displacement to form a fixing belt, which is mounted on a fixing unit, and an image forming apparatus (manufactured by Ricoh Company). Images obtained by image formation using IPSiO 8150) were evaluated.

  As a result, when the belts of Examples 1 to 4 (each of two types) were used, all the images were good, there was no problem with the fixing property at the joint portion, and both of them repeated 300,000 sheets. There was no abnormality in the evaluation.

  On the other hand, in the case of using the belt of Comparative Example 1, when the joining belt having a substrate circumference deviation of 0.08 mm is used, a non-glossy streak portion is seen at the center of the image forming region, and the continuous belt is continuously formed. In repeated evaluation, wrinkles gradually occurred on the transfer paper according to the repetition. On the other hand, when a joining belt having a deviation of 0.15 mm was used as the belt substrate, wrinkles occurred on the transfer paper from the beginning.

  Further, 10% by weight of ferrite fine powder was added to the commercially available polyimide varnish (polyamic acid solution) used in Example 2, and the mixture was stirred to prepare a coating solution. This coating solution is poured onto a glass flat plate to form a smooth surface with a predetermined thickness using a blade, and then dried at 120 ° C. in a heating furnace to remove the solvent, and then at a temperature of 160 ° C. Then, using a sheet partially imidized so that the self-adhesive property remains, this sheet is processed in the same manner as in Example 1, except that the dimensions are slightly smaller in the final imidization. Therefore, the final dimensions are slightly larger so as to be the same as those of the fixing belt according to the first embodiment, and the shape is similar to that of the processed sheet a.

  This self-adhesive sheet is bonded to a second fixing member (a magnetic body having a Curie point Tq2 of 310 ° C.) having a cylindrical shape as shown in FIG. The first fixing member having a substantially rectangular parallelepiped shape whose one surface is a concave surface that fits the side surface of the second fixing member is set on the bonded portion (the Curie point Tq2 is 350 ° C.). The fixing member is fixed, heated to 300 ° C. to complete imidization, and then the second fixing member is heated to 310 ° C. to lose the magnetism. The endless joining belt was removed from the second fixing member. A fixing belt was produced in the same manner as described above using the obtained endless belt as a base and evaluated. The image at that time was good, and there was no problem with the fixing property at the joint. No abnormalities were observed even after repeated evaluation up to the sheets.

<Example 5>
A polyimide sheet having a film thickness of 80 μm, prepared in the same manner as in Example 2, was cut into a width of 246 mm and a length of 805.4 mm, and both ends 10.0 mm in the width direction were different from each other at one end and the other end. Each of these was ground, and 45 μm was scraped off to provide a remaining 35 μm thick step to obtain a processed sheet g.

  Similarly, however, a processed sheet h having a width of 300 mm, a length of 800.4 mm, and 5.0 mm at both ends in the width direction, provided with a step having a grinding part thickness of 35 μm by grinding different surfaces. Obtained.

  The ground surfaces at both ends of these sheets have staggered steps as shown in model form in FIG.

  The same conductive silicone adhesive as in Example 1 was applied by screen printing to the stepped portion of the sheet thus prepared, that is, the bonded region at both ends. At this time, the thickness of the adhesive layer was set to 10 μm so as not to cause a step in the bonded portion.

  A sheet-like support (second fixing member) made of a magnetic material (Curie point Tq2 is 160 ° C.) having a heater built therein as shown in FIG. The both ends were bonded together while being set so that the bonding portion was positioned on the upper surface of the fixing member.

  Bonding using a flexible (flexible) sheet (a Curie point Tq1 of the magnetized body (magnet) of 260 ° C.) having a magnetized body (magnet) dispersed on the bonded part as the first fixing member After overlapping so as to cover the part, the adhesive was cured by heating at a temperature of 150 ° C. for 20 minutes. Thereafter, the temperature is raised to a temperature of the support of 165 ° C., the pressing member is removed (the operation at this time was very easy), the joined belt is removed from the support, and the joining length is thus reduced. Two different types of joining belts were obtained.

  When the circumferential length of the obtained joining belt was measured, the joining widths at both ends and the central part were within 795.4 mm ± 0.5 mm for both 10.0 mm and 5.0 mm products, and the circumference required as a transfer belt was required. The length deviation standard of 0.5 mm or less was satisfied, and there was no difference in circumferential length, which was good.

<Evaluation as transfer belt>
An intermediate transfer unit is formed by forming a release layer of fluororesin with a thickness of 5 μm on the surface of each of these joining belts, adjusting the axial direction to a predetermined dimension, and attaching a stop tape to prevent lateral displacement at both ends of the belt. The image was formed using an image forming apparatus (IPSiO CX400 manufactured by Ricoh Co., Ltd.), and the image was evaluated.

  As a result, it was found that an image having a good quality equivalent to the endless belt formed endless from the beginning by centrifugal molding can be obtained.

  INDUSTRIAL APPLICABILITY The present invention can be used for a general sheet joining method, and in particular, a full-color copier for superimposing toner images on a transfer material to form a full-color image, a belt having both functions of transfer and conveyance in a printer. (Transfer fixing belt or the like) and fixing belt can be preferably applied.

(A) It is a model cross section which shows the state which attached the level | step difference to the sheet | seat edge part to bond, and did not produce thickness spots. (B) It is model sectional drawing which shows the state which pinched | interposed the bonding part between the fixing members, and was fixed. (C) It is model sectional drawing which shows the state which performs a joining process so that a bonding part receives one mass of the said fixing member. (A) It is model sectional drawing which shows the state which attached the taper to the sheet | seat edge part to bond, and did not produce thickness spots. (B) It is model sectional drawing which shows the state which pinched | interposed the bonding part between the fixing members, and was fixed. (A) It is a model figure which shows the state which set one side of the fixing member as the column shape of a diameter smaller than the internal diameter of the belt manufactured, and made the other side a rectangular parallelepiped, and set the bonding part of the sheet | seat between both. (B) It is a model figure which shows the state which made one side of the fixing member the cylinder shape of the same diameter as the internal diameter of the belt manufactured, made the other a rectangular parallelepiped, and set the bonding part of the sheet | seat between both. (C) It is a figure which shows in model the example which set the bonding part of the sheet | seat 1 between these as the shape of the two fixing members 3 and 4 each as a rectangular parallelepiped. (D) It is a model figure which shows the example using the fixing member (code | symbol 5 in a figure) provided with the heater inside. (A) It is a model perspective view which shows the whole fixing belt produced using the endless joining belt which concerns on this invention as a base | substrate. (B) It is a model figure which shows the cross section of a junction part vicinity.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sheet | seat 2 Adhesive 3 Fixing member 4 Fixing member 5 Fixing member which consists of a magnetic body provided with the heater inside 6 Endless joining belt 7 Elastic layer 8 Release layer 9 Laminated belt

Claims (13)

In a joining member manufacturing method for obtaining a joining member by bonding different end portions of one sheet, or by adhering end portions of different sheets,
After bonding the other end to the end to which the thermosetting adhesive is applied, the bonded portion is bonded to the bonding when heated to the curing temperature of the thermosetting adhesive and bonded. After being sandwiched between a first fixing member made of a magnetized body arranged on one surface of the part and a second fixing member made of a magnetized body or magnetic material arranged on the other surface, the thermosetting adhesive A method for producing a joining member, which comprises heating to the curing temperature of the agent. The Curie point temperature Tq1 of the magnetized body of the first fixing member and the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member are both higher than the curing temperature T1 of the thermosetting adhesive,
The Curie point temperature Tq1 of the magnetized body of the first fixing member is higher than the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member, and
After heating to the curing temperature T1 of the thermosetting adhesive and joining the bonded portion, the second fixing member is set to a temperature lower than the temperature Tq1 and higher than the temperature Tq2, The joining member manufacturing method according to claim 1, wherein pinching of the joined joining member by the first securing member and the second securing member is eliminated. In a joining member manufacturing method for obtaining a joining member by bonding different end portions of one sheet, or by adhering end portions of different sheets,
After pasting the other end to the end of the self-heat-adhesive sheet, when heating to the bonding temperature of the self-heat-adhesive sheet by heat treatment means,
The bonding portion includes a first fixing member made of a magnetized body arranged on one surface of the bonding portion and a second fixing member made of a magnetized body or magnetic material arranged on the other surface. After the sandwiching, the joining member manufacturing method is characterized by heating to the bonding temperature of the self-heat-adhesive sheet. The Curie point temperature Tq1 of the magnetized body of the first fixing member and the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member are both higher than the adhesive temperature T2 of the self-thermoadhesive sheet,
The Curie point temperature Tq1 of the magnetized body of the first fixing member is higher than the Curie point temperature Tq2 of the magnetized body or magnetic body of the second fixing member, and
After heating to the bonding temperature T2 of the self-heat-adhesive sheet and bonding the bonded portion, the second fixing member is set to a temperature lower than the temperature Tq1 and higher than the temperature Tq2, The joining member manufacturing method according to claim 3, wherein pinching of the joined joining member by the first securing member and the second securing member is eliminated.   The method for manufacturing a joining member according to any one of claims 1 to 4, wherein the sheet is made of a sheet member in which magnetic powder is dispersed.   The joining member manufacturing method according to claim 5, wherein the heat treatment apparatus is an electromagnetic induction heat treatment apparatus.   The heating at the curing temperature of the thermosetting adhesive is performed such that a load due to one mass of the fixing member is applied to the bonded portion. The joining member manufacturing method of claim | item.   The joining member manufacturing method according to claim 1, wherein the fixing member has flexibility.   An endless joining belt produced by the joining member manufacturing method according to any one of claims 1 to 8.   A fixing unit using the endless joining belt according to claim 9.   An intermediate transfer unit using the endless joining belt according to claim 9.   An image forming apparatus comprising a fixing unit using the endless joining belt according to claim 9 and / or an intermediate transfer unit.   In a sheet bonding apparatus for bonding two overlapped sheet end portions by heat bonding, a first fixing member made of a magnetized body and a second fixing made of a magnetized body or a magnetic material for sandwiching the bonded portion A sheet bonding apparatus comprising: a member.

Images