JP4785145B2 - Fixing roller, fixing device and image forming apparatus - Google Patents

Description

The present invention relates to a fixing roller (hereinafter sometimes referred to as an “elastic roller” in the present invention ) , a fixing device, and an image forming apparatus. More specifically, for example, when mounted on a fixing device of an image forming apparatus, The present invention relates to an elastic roller that contributes to the formation of a high-quality image over a long period of time and also contributes to an improvement in durability of the fixing device, and a fixing device and an image forming apparatus including the elastic roller.

  Various image forming apparatuses using an electrophotographic system are employed in printers such as laser printers and video printers, copiers, facsimiles, and multi-function machines thereof. Various image forming apparatuses include a fixing device equipped with a fixing roller or the like that incorporates a heating unit such as a heating element in order to fix the developer image transferred to the recording medium. Since such a fixing device includes a fixing roller incorporating a heating unit therein, the preheating time is usually relatively long, the configuration thereof is complicated, and it is difficult to replace only the heating unit, etc. Problems may occur.

  As a fixing device that can solve at least one of these problems, a fixing device including an external heating unit that supplies heat to a fixing roller or the like from the outside can be cited. Examples of such external heating means include radiant heating means such as a halogen heater, direct heating means by contact, induction heating means by AC magnetic field formation, and the like. In the fixing device provided with these external heating means, the fixing roller is made of metal on the outer peripheral surface of the elastic layer, for example, as a heated part so that the fixing roller is efficiently heated by the heat from the external heating means. It has a coating. For example, Patent Document 1 describes a heating rotator “characterized by including an elastic layer inside and a metal sleeve having a thickness of 10 to 150 μm provided outside thereof”.

  Further, in Patent Document 2, “a fixing roller capable of continuing a usable state for a long period of time without cracking at the end portion” of the metal sleeve in the heating rotating body described in Patent Document 1 is disclosed. (Refer to column 0017 of Patent Document 2.) “A metal core, a sponge layer disposed on the outer periphery of the metal core, and a metal thin sleeve coated on the outer periphery of the sponge layer; The fixing roller is characterized in that the end portion of the thin metal sleeve is positioned so as not to protrude outwardly in the axial direction from the end portion of the sponge layer. (See claim 1 of Patent Document 2).

JP-A-8-129313 JP 2004-205814 A

  The present invention provides an elastic roller that contributes to the formation of a high-quality image over a long period of time, for example, when mounted on a fixing device of an image forming apparatus, and also contributes to improving the durability of the fixing device. With the goal. Another object of the present invention is to provide a fixing device excellent in durability that contributes to the formation of a high-quality image over a long period of time. Furthermore, an object of the present invention is to provide an image forming apparatus capable of forming a high-quality image over a long period of time.

As means for solving the problems,
According to a first aspect of the present invention, there is provided a foam elastic layer formed on the outer peripheral surface of the shaft body and a metal made on the outer peripheral surface of the foam elastic layer so that both end portions of the foam elastic layer protrude in the axial direction. An end adhesive having an outer diameter equal to or less than an outer diameter of the sleeve and an outer peripheral surface of the both ends of the foamed elastic layer protruding from the sleeve so as to contact the end of the sleeve A fixing roller characterized by comprising a layer,
The fixing roller according to claim 1, wherein an adhesive layer is provided between the foamed elastic layer and the sleeve.
The fixing roller according to claim 1 or 2, wherein the end adhesive layer has an outer diameter that gradually decreases toward the end.
A fourth aspect of the present invention is a fixing device including the fixing roller according to any one of the first to third aspects,
A fifth aspect of the present invention is an image forming apparatus including the fixing roller according to any one of the first to third aspects.

  The elastic roller according to the present invention has an outer diameter equal to or smaller than the outer diameter of the sleeve, and includes end adhesive layers respectively formed at both ends of the foamed elastic layer protruding from the sleeve. Even if it is rotationally driven and stopped, the end of the sleeve can be prevented from peeling off by the formed end adhesive layer. As a result, the elastic roller according to the present invention can contribute to the formation of a high-quality image, and since the foamed elastic layer and the sleeve are not easily damaged, the elastic roller itself has excellent durability and is mounted. The possibility of destroying the contacted body in the fixing device is very small. Therefore, according to the present invention, for example, when mounted on a fixing device of an image forming apparatus, the elastic roller contributes to forming a high-quality image over a long period of time and also improves the durability of the fixing device. Can be provided.

  Further, since the fixing device and the image forming apparatus according to the present invention include the elastic roller according to the present invention, according to the present invention, the durability that contributes to forming a high-quality image over a long period of time is excellent. A fixing device and an image forming apparatus capable of forming a high-quality image over a long period of time can be provided.

  As shown in FIGS. 1 and 2, an elastic roller 1 </ b> A as an embodiment of the elastic roller according to the present invention includes a foamed elastic layer 3 formed on the outer peripheral surface of the shaft body 2 and both ends of the foamed elastic layer 3. The sleeve 4 provided on the outer peripheral surface of the foamed elastic layer 3 so that each of the portions 3A and 3B protrudes in the axial direction, and the foamed elastic layer having an outer diameter equal to or smaller than the outer diameter of the sleeve 4 and protruding from the sleeve 4 3 and an end adhesive layer 6 formed on the outer peripheral surfaces of both end portions 3A and 3B.

  The shaft body 2 only needs to have good conductive properties, and is also referred to as a so-called “core metal”.

  The foamed elastic layer 3 is formed on the outer peripheral surface of the shaft body 2 by a rubber composition described later. The foamed elastic layer 3 is a foamed elastic layer having cells on its inner and / or outer surface (cells opened on the outer peripheral surface of the elastic layer 3 in FIG. 1 and cross section of the elastic layer 3 in FIG. 2). None of the open cells are shown.) When the foamed elastic layer 3 has cells, the hardness of the foamed elastic layer 3 is lowered and the function of the elastic roller 1 is improved, which can contribute to forming a high-quality image. Here, the cell having the foamed elastic layer 3 includes a hollow region generated by foaming or decomposition of a foaming agent contained in the rubber composition, and a hollow region derived from a hollow filler contained in the rubber composition. Say. The plurality of cells in the foamed elastic layer 3 are in a state where they do not contact or communicate with other cells (referred to as independent cell states), a state where they contact or communicate with other cells (communication cell state) Or the independent cell state and the communication cell state may coexist. The foamed elastic layer 3 has a cell size, a presence rate, and the like determined according to various rollers used in the image forming apparatus.

  For example, the average cell diameter of the cells in the foamed elastic layer 3 is preferably 60 to 800 μm, and particularly preferably 100 to 400 μm. When the average cell diameter of the cell is within the above range, the adhesive quickly penetrates into the cell when an adhesive described later is applied to the outer peripheral surface of the foamed elastic layer 3, and the adhesive layer 5 Strongly formed on the outer peripheral surface. The cells in the foamed elastic layer 3 preferably have an average cell wall width of 0.01 to 0.5 mm, particularly preferably 0.05 to 0.4 mm. When the average width of the cell wall is within the above range, the adhesive layer 5 is firmly formed on the outer peripheral surface of the foamed elastic layer 3 and the foamed structure in the foamed elastic layer 3 even under a pressure environment described later. Can be effectively prevented from being damaged, cracked and broken. Moreover, it is preferable that the foaming rate in the foaming elastic layer 3 is 150 to 480%, and it is especially preferable that it is 200 to 450%. When the foaming rate is in the above range, the adhesive layer 5 is firmly formed on the outer peripheral surface of the foamed elastic layer 3, and the foamed structure in the foamed elastic layer 3 is damaged even under a pressure environment described later. Cracking and breaking can be effectively prevented. In the cell, the average cell diameter, the average width of the cell wall, and the foaming rate are the blending amount of the foaming agent or the hollow filler contained in the rubber composition described later forming the foamed elastic layer 3, the size of the hollow filler, It can be adjusted depending on the curing conditions of the rubber composition.

The average cell diameter of the cell is determined by observing an area of about 2 mm ² with an electron microscope or the like on the surface of the foamed elastic layer 3 or a cut surface obtained by cutting an arbitrary surface. Can be obtained as an average length obtained by arithmetically averaging the measured maximum length. As for the average width of the cell wall in the cell, an area of about 2 mm ² is observed with an electron microscope or the like on the surface of the elastic layer 3 or the cut surface when the elastic layer 3 is cut at an arbitrary surface, like the average cell diameter. Then, the distance between the cells existing in the observation visual field, that is, the width of the wall between the cells can be measured, and the measured value can be obtained by arithmetic averaging. The expansion ratio of the foamed elastic layer 3 can be calculated from the volume and mass of the foamed elastic layer 3 measured by a conventional method.

  The foamed elastic layer 3 preferably has an Asker C hardness of 20-60. When the Asker C hardness is within the above range, a desired contact state or pressure contact state with respect to the contacted body can be maintained, which contributes to forming a high-quality image. For example, when the elastic roller 1 is mounted on the image forming apparatus as a fixing roller, a desired pressure contact state is maintained with respect to the pressure roller, and the nip width formed by the pressure roller and the fixing roller is increased. Therefore, the developer image transferred to the recording medium can be fixed as desired, and as a result, it can contribute to forming a high-quality image. The Asker C hardness can be a value obtained by measuring a plurality of locations of the foamed elastic layer 3 in accordance with JIS K6253 and arithmetically averaging the measured values. The Asker C hardness of the foamed elastic layer 3 is, for example, selecting the type of rubber and / or additive contained in the rubber composition forming the foamed elastic layer 3 and / or changing the blending amount thereof. In addition, it can be adjusted according to the molding conditions of the foamed elastic layer 3 and the like.

  The thickness of the foamed elastic layer 3 is not particularly limited, but is usually preferably adjusted to 2 to 20 mm, and particularly preferably adjusted to 3 to 12 mm.

  The sleeve 4 is provided on the outer peripheral surface of the adhesive layer 5. The sleeve 4 is formed of a metal material having high thermal conductivity such as iron, stainless steel, nickel, etc., and may have a single layer structure or a laminated structure in which two or more layers are laminated. The sleeve 4 has a single layer structure or a laminated structure, and is usually formed in a thin layer. For example, the entire thickness is preferably 20 to 150 μm, and preferably 30 to 100 μm. Particularly preferred. It is preferable that the sleeve 4 has a tensile strength of about 800 to 1300 MPa because it is difficult to be deformed by the pressure contact from the inner peripheral surface of the foamed elastic layer 3. The measuring method of the tensile strength is based on JIS Z 2241.

  The sleeve 4 is adjusted such that its axial length is shorter than the axial length of the foamed elastic layer 3. The length of the sleeve 4 in the axial direction can secure a length enough to form an end adhesive layer 6 to be described later on both ends 3A and 3B of the foamed elastic layer 3 protruding from the sleeve 4. For example, the length is adjusted to about 90 to 97% with respect to the length of the foamed elastic layer 3 in the axial direction. As shown in FIGS. 1 and 2, the sleeve 4 has both end portions 3 </ b> A and 3 </ b> B of the foamed elastic layer 3, preferably, regions near both end portions 3 </ b> A and 3 </ b> B of the foamed elastic layer 3. In other words, the elastic foam layer 3 is provided on the outer peripheral surface of the elastic foam layer 3 so as to penetrate the sleeve 4 so as to protrude from both ends.

  As shown in FIGS. 1 and 2, the end adhesive layer 6 is in contact with the end of the sleeve 4 on the outer peripheral surface in the region in the vicinity of both ends 3A and 3B of the foamed elastic layer 3 protruding from the sleeve 4. And up to the end of the foamed elastic layer 3. When the end adhesive layer 6 is formed on the outer peripheral surface in the region in the vicinity of both end portions 3A and 3B of the foamed elastic layer 3 in this way, the end portion of the sleeve 4 is formed by the end adhesive layer 6 so that the foamed elastic layer 3 Even if the elastic roller 1A is mounted on the fixing device and repeatedly rotated at a high speed and stopped, the end of the sleeve 4 is peeled off from the surface of the foamed elastic layer 3. Therefore, it is possible to prevent cracks at both end portions 3A and 3B of the foamed elastic layer 3 from being damaged and the foamed structure of the foamed elastic layer 3 from being damaged or damaged.

  The end adhesive layer 6 has an outer diameter equal to or smaller than the outer diameter of the sleeve 4. When the thickness of the end adhesive layer 6 is adjusted in this way, the pressure in the direction perpendicular to the axial direction of the shaft body 2 (center direction of the shaft body 2) applied when the elastic roller 1 is driven to rotate at high speed. Preventing the end portion of the sleeve 4 and the end portion of the foamed elastic layer 3 from being separated by the elastic force and adhesive force of the end adhesive 6 and preventing the foamed elastic layer 3 from being cracked or the like. Can do. The thickness of the end adhesive layer 6 is preferably, for example, 50 to 100% with respect to the outer diameter of the sleeve 4, that is, the thickness from the surface of the foamed elastic layer 3 to the surface of the sleeve 4, It is particularly preferably 70 to 100%. Specifically, the thickness of the end adhesive layer 6 is preferably 10 to 150 μm, and particularly preferably 14 to 150 μm. The thickness of the end adhesive layer 6 may be uniform or non-uniform in the axial direction of the foamed elastic layer 3. In the elastic roller 1A, the thickness of the end adhesive layer 6 is foamed elastic. The layer 3 is adjusted substantially uniformly in the axial direction.

  The end adhesive layer 6 is a cured body obtained by curing a curable material, and firmly fixes both ends of the sleeve 4 to prevent the end of the sleeve 4 from peeling off for a long period of time. In addition, it is preferable in that it is possible to prevent cracks at both end portions 3A and 3B of the foamed elastic layer 3 from being broken and damage the foamed structure of the foamed elastic layer 3 over a long period of time. Examples of the curable substance that forms the cured body include various adhesives and various resins. Specifically, examples of the various adhesives include silicone adhesives and acrylic adhesives. Examples of the silicone-based adhesive include non-flowable adhesives such as trade names “KE-44” and “KE-45” (both manufactured by Shin-Etsu Chemical Co., Ltd.), addition-type silicone RTV, and condensation-type silicone RTV. These fluid adhesives are mentioned. Examples of the addition type silicone RTV include a trade name “KE1880” (viscosity (25 ° C.) 84 Pa · s), a trade name “KE1830” (viscosity (25 ° C.) 110 Pa · s), and a trade name “KE1833” (viscosity (25 (° C.) 150 Pa · s) (both manufactured by Shin-Etsu Chemical Co., Ltd.) and the like. As the condensation type silicone RTV, for example, trade name “KE441” (viscosity (25 ° C.) 15 Pa · s, Shin-Etsu Chemical Co., Ltd.) Manufactured) and the like. Examples of acrylic adhesives include acrylic-modified silicone resins. Specifically, as a flowable acrylic-modified silicone resin, a trade name “Super X 8008” (viscosity (25 ° C.) 90 Pa · s), product Name “Super X 8008 LL Black” (viscosity (25 ° C.) 14 Pa · s) and trade name “Super X 8008 Clear” (viscosity (25 ° C.) 65 Pa · s) (both manufactured by Cemedine Co., Ltd.)) and the like. . Moreover, as various resin, a liquid silicone resin etc. are mentioned, for example.

  Further, since the elastic roller 1 may be used under heating, it is preferable that various adhesives and various resins have heat resistance, and specifically, have heat resistance of about 150 to 250 ° C. It is preferable. The heat resistance is measured by a softening temperature measurement method defined in JIS K 6833.

  Other properties required for various adhesives and various resins include tensile shear adhesive strength in cured products of various adhesives and various resins. In the present invention, in cured products of various adhesives and various resins. The tensile shear bond strength is preferably 0.5 to 4 MPa. When the tensile shear adhesive strength in the cured products of various adhesives and various resins is within the above range, both ends 3A and 3B of the foamed elastic layer 3 are prevented from greatly expanding, and the end of the sleeve 4 is foamed. Peeling from the surface of the elastic layer 3 can be prevented. The tensile shear bond strength is measured according to JIS K 6249 using a cured product obtained by curing various adhesives and various resins as a test sample.

  As shown in FIG. 3, an elastic roller 1 </ b> B as another embodiment of the elastic roller according to the present invention includes a foamed elastic layer 3 formed on the outer peripheral surface of the shaft body 2 and both ends of the foamed elastic layer 3. A sleeve 4 provided on the outer peripheral surface of the foamed elastic layer 3, an adhesive layer 5 formed between the foamed elastic layer 3 and the sleeve 4, and the sleeve 4 so that each of 3 A and 3 B protrudes in the axial direction. And an end adhesive layer 6 formed on the outer peripheral surfaces of both end portions 3A and 3B of the foamed elastic layer 3 protruding from the sleeve 4, respectively.

  The shaft body 2, the foamed elastic layer 3 and the sleeve 4 in the elastic roller 1B are basically the same as the shaft body 2, the foamed elastic layer 3 and the sleeve 4 in the elastic roller 1A.

  The adhesive layer 5 is interposed between the foamed elastic layer 3 and the sleeve 4 to adhere the foamed elastic layer 3 and the sleeve 4. The adhesive forming the adhesive layer 5 is not particularly limited as long as it is an adhesive that can bond the foamed elastic layer 3 and the sleeve 4. For example, a silicone-based adhesive (trade name “KE-44”, “KE-45” and “KE-441”, both manufactured by Shin-Etsu Chemical Co., Ltd.) and the like. In the present invention, the adhesive is fluid at room temperature (25 ° C.), specifically, a fluid adhesive having a viscosity at 25 ° C. of 15 to 150 Pa · s in the adhesive coating layer. It is preferable in that bubbles can be prevented from being generated and mixed, and the foamed elastic layer 3 and the sleeve 4 can be firmly bonded. As for the fluidity in the fluid adhesive, the viscosity at 25 ° C. is preferably 15 to 150 Pa · s, more preferably 30 to 120 Pa · s, and particularly preferably 50 to 100 Pa · s. When the viscosity of the fluid adhesive is within the above range, bubbles and the like are generated in the adhesive coating layer, and bubbles and the like can be effectively prevented from being mixed. The viscosity of the fluid adhesive is measured according to JIS K 6249 (using a BH viscometer).

  Examples of the fluid adhesive include a silicone adhesive and an acrylic adhesive. Specifically, as silicone adhesives, addition type silicone RTV, condensation type silicone RTV, acrylic modified silicone resin, and the like exemplified as flowable adhesives applicable to the end adhesive layer 6 of the elastic roller 1A. Can be mentioned. The fluid adhesive may be one-component or two-component, and may be thermosetting or moisture curable. Furthermore, the fluid adhesive may be adjusted using a diluent such as toluene and xylene so that the viscosity is within the above range.

  The adhesive forming the adhesive layer 5 preferably has a heat resistance of, for example, about 150 to 250 ° C., like the adhesive forming the end adhesive layer 6. Other properties required for the adhesive forming the adhesive layer 5 include tensile shear bond strength in a cured product of the adhesive. In this invention, tensile shear adhesion in a cured product of the adhesive is used. The strength is preferably 0.5-4 MPa. When the tensile shear adhesive strength of the cured adhesive is within the above range, the sleeve 4 and the foamed elastic layer 3 are firmly bonded with a sufficient adhesive force. The tensile shear bond strength is measured in the same manner as the adhesive forming the end adhesive layer 6.

  Although the thickness of the adhesive bond layer 5 is not specifically limited, Usually, it is preferable to adjust to 10-300 micrometers, and it is especially preferable to adjust to 10-100 micrometers.

  It is preferable that the adhesive layer 5 is formed of the same adhesive as that of the end adhesive layer 6 described later in that the elastic roller 1B can be easily manufactured.

  The end adhesive layer 6 is basically the same as the end adhesive layer 6 in the elastic roller 1 </ b> B, except that its thickness gradually decreases toward the end of the foamed elastic layer 3. For example, as described above, the thickness of the end adhesive layer 6 is the thickness from the surface of the foamed elastic layer 3 to the surface of the sleeve 4, that is, in the elastic roller 1B, the adhesive layer 5 and the sleeve 4 The total thickness is preferably 50 to 100%, particularly preferably 70 to 100%.

  As shown in FIG. 3, when the end adhesive layer 6 is formed in contact with the end of the sleeve 4, the end of the sleeve 4 is firmly attached to the foamed elastic layer 3 by the end adhesive layer 6. Since the elastic roller 1B is mounted on the fixing device and repeatedly rotated at a high speed and stopped, the end of the sleeve 4 is effectively peeled off from the surface of the foamed elastic layer 3 because the elastic roller 1B can be bonded. Therefore, both ends 3A and 3B of the foamed elastic layer 3 are cracked, and the foamed structure of the foamed elastic layer 3 is prevented from being damaged and damaged.

  An example of a manufacturing method for manufacturing the elastic roller according to the present invention (hereinafter sometimes referred to as a manufacturing method according to the present invention) will be described below. In the manufacturing method according to the present invention, a roller base body 7 having a foamed elastic layer 3 on the outer peripheral surface of the shaft body 2 is inserted into the sleeve 4 under a pressurized environment or a decompressed environment, and the foaming projecting from the sleeve 4 is inserted. An adhesive is applied to the outer peripheral surfaces of both end portions 3A and 3B of the elastic layer 3 and cured.

  In the manufacturing method according to the present invention, first, as shown in FIG. 4, a roller base body 7 having a foamed elastic layer 3 on the outer peripheral surface of the shaft body 2 is prepared.

  The shaft body 2 is made of, for example, a metal such as iron, aluminum, stainless steel, brass or an alloy thereof, a resin such as a thermoplastic resin or a thermosetting resin, and carbon black or metal powder as a conductivity-imparting agent for the resin. It is prepared in a desired shape by a known method using a material such as a conductive resin blended with a body. When the shaft body 2 is required to have conductivity, in addition to the metal and the conductive resin, the surface of the insulating core body formed of the resin or the like is plated by a regular method to thereby form the shaft body 2. Can be formed. Among the materials, a metal is preferable because it can easily impart conductivity, and free cutting steel, aluminum, or stainless steel is particularly preferable.

  The shaft body 2 may be coated with a primer layer on its outer peripheral surface as desired. The primer for forming the primer layer is dissolved in a solvent or the like as desired, and is applied to the outer peripheral surface of the shaft body 2 according to a conventional method such as a dipping method or a spray method, and is cured. The primer is not particularly limited. For example, alkyd resin, phenol-modified silicone modified alkyd resin, oil-free alkyd resin, acrylic resin, silicone resin, epoxy resin, fluororesin, phenol resin, polyamide resin, Examples thereof include urethane resins and mixtures thereof. If desired, a crosslinking agent for curing and / or crosslinking the resin can be used. Examples of such a crosslinking agent include isocyanate compounds, melamine compounds, epoxy compounds, peroxides, phenol compounds, and hydrogen siloxane compounds. Etc. The primer layer is formed with a thickness of 0.1 to 10 μm, for example.

  Next, in the method for manufacturing a roller according to the present invention, the rubber composition described later disposed on the outer peripheral surface of the shaft body 2 formed in this way is cured to form the foamed elastic layer 3. For example, the foamed elastic layer 3 is formed on the outer peripheral surface of the shaft body 2 by performing molding and heat curing simultaneously or continuously by a known molding method. The molding method of the rubber composition is not particularly limited as long as the rubber composition can be disposed on the outer peripheral surface of the shaft body 2, and is particularly limited to, for example, continuous vulcanization by extrusion molding, press molding, and molding by injection. It is not something. For example, when the rubber composition is an addition reaction type foamed silicone rubber composition described later, extrusion molding or the like can be selected as the molding method. The rubber composition forming the foamed elastic layer 3 will be described later.

  The curing conditions of the rubber composition are such that when the rubber composition disposed on the outer peripheral surface of the shaft body 2 is cured and contains a foaming agent, the curing condition is sufficient for the foaming agent to decompose or foam. It is well adjusted depending on the composition of the rubber composition, the type of foaming agent, and the like. For example, when the rubber composition is an addition reaction type foamed silicone rubber composition to be described later, the curing conditions are usually 100 to 400 ° C., particularly 200 to 400 ° C., several minutes to 1 hour, particularly A heating time of 5 minutes or more and 30 minutes or less is preferable in that the foamed elastic layer 3 can have independent cells having an average cell diameter in the above range and have a foaming rate in the above range.

  In the manufacturing method according to the present invention, the foamed elastic layer 3 thus cured can be secondarily cured as necessary. Although the secondary curing conditions are not particularly limited, for example, when the rubber composition is an addition reaction type foamed silicone rubber composition described later, the secondary curing conditions remain in the cured state, 180 to A heating temperature of 250 ° C., in particular 190 to 230 ° C., and a heating time of 1 to 24 hours, in particular 3 to 10 hours, are preferred.

  In the manufacturing method according to the present invention, the foamed elastic layer 3 formed as described above can be subjected to an elastic layer adjusting process as necessary. In the elastic layer adjustment processing, the foamed elastic layer 3 is adjusted to a desired size by using a machining device such as a polishing device, a grinding device, and a cutting device, or an instrument, and / or the foamed elastic layer 3 This is a process for adjusting the surface state to a desired state or the like. Examples of the elastic layer adjustment processing include polishing, grinding, and cutting.

  The foamed elastic layer 3 formed in this way has an outer diameter larger than the inner diameter of the sleeve 4 to be described later. For example, the foamed elastic layer 3 has an outer diameter of 100 to 105% with respect to the inner diameter of the sleeve 4. It is good that it has an outer diameter of 100 to 102%. When the outer diameter of the foamed elastic layer 3 is adjusted to the above range, the foamed elastic layer 3 rapidly shrinks in a pressure environment described later, and when the pressure environment is released, the foamed elastic layer 3 is quickly restored. . The foamed elastic layer 3 has a length in the axial direction that is longer than the length in the axial direction of a sleeve 4 to be described later.

  In this manner, the roller base body 7 shown in FIG. 4 in which the foamed elastic layer 3 is formed on the outer peripheral surface of the shaft body 2 can be manufactured.

  On the other hand, in the manufacturing method according to the present invention, the sleeve 4 is prepared. The sleeve 4 is formed of a cylindrical body having openings at both ends of the metal material. The sleeve 4 is adjusted to a thickness of 20 to 150 μm, for example, and the inner diameter thereof is smaller than the outer diameter of the foamed elastic layer 3. For example, the outer diameter of the foamed elastic layer 3 is smaller than the inner diameter of the sleeve 4. Thus, the adjustment is made so as to be in the range described later. Further, the sleeve 4 is adjusted such that its axial length is shorter than the axial length of the foamed elastic layer 3. The sleeve 4 is formed into a cylindrical body by, for example, a spinning method or an ironing method. The sleeve 4 is preferably adjusted so that at least the outer peripheral surface is smooth.

In the manufacturing method according to the present invention, if desired, an adhesive is applied to the outer peripheral surface of the foamed elastic layer 3 in the roller base body 7 and the region where the sleeve 4 is provided. This adhesive is preferably uniformly applied to the outer peripheral surface of the foamed elastic layer 3 and the region where the sleeve 4 is provided. The method of applying the adhesive to the outer peripheral surface of the foamed elastic layer 3 and the region where the sleeve 4 is provided is not particularly limited, and examples thereof include a spray method, a dipping method, a ring coater method, and a roll coater method. When the adhesive is applied to the area on the outer peripheral surface of the foamed elastic layer 3 where the sleeve 4 is provided, the adhesive can be appropriately diluted with a diluent or the like. The fluid adhesive can be uniformly and easily applied to the outer peripheral surface of the foamed elastic layer 3 and the region where the sleeve 4 is provided, and bubbles and the like are generated in the application layer to which the adhesive is applied. Or, it is possible to effectively prevent air bubbles and the like from being mixed. As a result, the foamed elastic layer 3 and the sleeve 4 can be firmly bonded. The applied amount of the adhesive may be adjusted so that the thickness of the adhesive layer 5 falls within the above range. For example, in the case of a silicone composition, 0.01 to 0.1 g / cm ^2. Adjusted to degree.

  In the manufacturing method according to the present invention, the roller base material 7 coated with an adhesive as desired is then inserted into the sleeve 4 in a pressurized environment or a reduced pressure environment at room temperature or under heating.

  A method of inserting the roller base body 7 into the sleeve 4 under a pressure environment (hereinafter referred to as a pressure method) will be described. As an apparatus used in the pressurization method, the foamed elastic layer 3 of the roller base body 7 can be reduced in diameter, and the roller base body 7 can be inserted into the sleeve 4 with the diameter of the foamed elastic layer 3 reduced. Any apparatus may be used, and examples thereof include a pressurizing apparatus 10 shown in FIG. A pressure device 10 shown in FIG. 5 is installed inside a cylindrical casing 11 that houses the roller base body 7 and the sleeve 4 in series in the axial direction thereof, and in the vicinity of one opening of the casing 11. , A mounting member 15 for mounting the sleeve 4, closed end portions 12 and 13 for closing the opening portions at both ends of the housing 11, and insertion for inserting the roller base 7 housed in the housing 11 into the sleeve 4 The apparatus 20 and the pressurizer 14 which pressurizes the inside of the housing | casing 11 are provided.

  As shown in FIG. 5, the casing 11 only needs to be able to accommodate the roller base body 7 and the sleeve 4 in series in the axial direction thereof. In the pressurizing device 10, the casing 11 is formed into a hollow cylindrical body. Has been. The mounting member 15 only needs to be able to support the sleeve 4 at a predetermined position. In the pressurizing device 10, the mounting member 15 protrudes from the inner peripheral surface of the housing 11 toward the center and supports the sleeve 4. A ring-shaped protrusion having a placement surface 16 is provided. The mounting member 15 is provided in the vicinity of one opening in the housing 11, that is, when the closed end 13 is attached to the housing 11, the clamping member 24 and the sleeve 4, which will be described later, between the mounting member 15 and the mounting member 15. It is formed in a position where a sufficient space is defined to arrange the end portion 3A of the foamed elastic layer 3 protruding from the end portion. The protruding amount of the mounting member 15 is adjusted to a protruding amount that allows the sleeve 4 to be mounted and allows the foamed elastic layer 3 having a reduced diameter to pass under a pressurized environment. By the mounting surface 16 of the mounting member 15, the sleeve 4 is supported at a position where the roller base 7 supported by the insertion device 20 described later is inserted, preferably at a position coaxial with the roller base 7. Is done. The closed end portions 12 and 13 have a through hole that allows the insertion device 20 described later to move in the axial direction, for example, and can close both end openings of the housing 11. Is formed in a cylindrical body provided with a sealing member 17 in the through hole. The sealing member 17 hermetically seals the insertion device 20 and the closed end portions 12 and 13. The pressurizer 14 only needs to be able to pressurize the inside of the casing 11 closed by the closed end portions 12 and 13 to, for example, about 0.48 MPa. For example, a compressor or the like is employed.

  As shown in FIG. 5, the insertion device 20 supports the roller base body 7, the casing 11, the mounting member 15, the sleeve 4 supported by the mounting member 15, and the closed end 12 and 13, a pair of support shafts 21 and 22 that pass through, preferably coaxially, and can be moved back and forth in the axial direction, and the opposite ends of the support shafts 21 and 22 are connected to the shaft body 2 of the roller base body 7. It has clamping members 23 and 24 that fix the ends and support the roller base body 7. The clamping members 23 and 24 only need to be able to fix the end of the shaft body 2. For example, the clamping members 23 and 24 may be configured to grip and fix the outer peripheral surface of the shaft body 2. You may be comprised so that a surface may be clamped and fixed.

  As shown in FIG. 5, in the pressurizing method using the pressurizing device 10, the casing 11 and the closed end portions 12 and 13 are assembled, and the sleeve 4 manufactured as described above is placed on the mounting member 15. The sleeve 4 is placed at a predetermined position. Next, if desired, both ends of the shaft body 2 in the roller base body 7 provided with the foamed elastic layer 3 having an adhesive coated on the outer peripheral surface are fixed to the sandwiching members 23 and 24, and a pair of support shafts 21 and 22 is provided. The roller base 7 is sandwiched between the casing 11, the mounting member 15, the sleeve 4 supported by the mounting member 15 and the closed end 13, and the roller base 7 is inserted into the sleeve. 4 is arranged in series in the upstream direction, and the casing 11 is closed by the closed end 12 to assemble the pressurizing device 10.

Next, the pressurizer 14 is activated to pressurize the inside of the pressurizing device 10 to a predetermined pressure, and pressurize the foamed elastic layer 3 of the roller base material 7 in a predetermined pressure environment. Then, since the foamed elastic layer 3 is pressurized with the gas in the cell and the cell itself shrinks and the foamed elastic layer 3 also shrinks, its outer diameter gradually decreases and becomes smaller than the inner diameter of the sleeve 4. . At this time, the pressure in the pressure device 10 and the time during which the roller base body 7 is placed in the pressure environment may be such that the outer diameter of the foamed elastic layer 3 is smaller than the inner diameter of the sleeve 4. The pressure in the pressurizing device 10 is preferably adjusted to 0.15 to 0.48 MPa, particularly preferably adjusted to 0.17 to 0.48 MPa, and the time in which the pressure is placed in the pressure environment is preferable. Is, for example, preferably from several seconds to 5 minutes, and particularly preferably from several seconds to 3 minutes. The ratio of shrinkage in the radial direction of the foamed elastic layer 3 under the pressure environment is, for example, about 65 to 99.5% of the thickness (initial thickness) of the foamed elastic layer 3 at normal pressure. This is preferable in that it does not damage the foamed structure of the foamed elastic layer 3 and has excellent resilience when the pressure is released, and is particularly preferably 80 to 99%. The shrinkage rate of the foamed elastic layer 3 is calculated as follows. First, a roller base body 7 is inserted into each of a plurality of master rings in which a plurality of master ring gauges having a predetermined inner diameter are arranged in series in order of increasing inner diameter, and the outer peripheral surface of the foamed elastic layer 3 in the roller base body 7 A test body holding a plurality of master ring gauges arranged in series is prepared. Next, in the pressure device 10, the pressure in the pressure device 10 is changed to shrink the foamed elastic layer 3 of the test body, and a master having an inner diameter corresponding to the degree of contraction of the foamed elastic layer 3. Drop the ring gauge in order. The thickness t ₁ (mm) of the foamed elastic layer 3 after shrinkage is obtained by using the inner diameter of the master ring gauge that has finally dropped as the outer diameter of the foamed elastic layer 3 after shrinkage in the roller base body 7. From the thickness t ₁ (mm) thus determined and the thickness t ₀ (mm) of the foamed elastic layer 3 before being reduced (reduced), the formula (t ₁ / t ₀ ) × 100 ( %), The shrinkage ratio of the foamed elastic layer 3 is calculated.

  In this way, in a state where the outer diameter of the foamed elastic layer 3 is smaller than the inner diameter of the sleeve 4, the pair of support shafts 21 and 22 in the insertion device 20 are manually or automatically moved to the sleeve 4 side (in FIG. 5). As shown in FIG. 6, the roller base material 7 supported by the insertion device 20 is moved forward until the end 3 </ b> A of the foamed elastic layer 3 protrudes from the end of the sleeve 4. Insert inside. At this time, the holding member 24 of the insertion device 20 has an outer diameter smaller than the outer diameter of the foamed elastic layer 3, and the mounting member 15 is installed at the above-described position, and thus protrudes from the end of the sleeve 4. The end portion 3 </ b> A of the foamed elastic layer 3 and the clamping member 24 reach the space defined between the mounting member 15 and the closed end portion 13 via the inside of the sleeve 4. Since the length of the sleeve 4 in the axial direction is adjusted as described above, the end portion 3B of the foamed elastic layer 3 is not inserted into the sleeve 4 as shown in FIG. In this way, the roller base body 7 provided with the foamed elastic layer 3 in which an adhesive is applied to the outer peripheral surface as desired can be inserted into the sleeve 4.

  Next, a method for inserting the roller base body 7 into the sleeve 4 under a reduced pressure environment (hereinafter referred to as a reduced pressure method) will be described. As an apparatus used in the pressure reduction method, the foamed elastic layer 3 of the roller base body 7 can be reduced in diameter, and the roller base body 7 can be inserted into the sleeve 4 with the diameter of the foamed elastic layer 3 reduced. Any device may be used, and examples thereof include a decompression device 30 shown in FIG. The decompression device 30 shown in FIG. 7 is basically the same as the pressurization device 10 shown in FIG. 5 except that a decompression device 31 is provided instead of the pressurization device 14. That is, the decompression device 30 is disposed inside a cylindrical casing 11 that houses the roller base body 7 and the sleeve 4 in series in the axial direction thereof, and in the vicinity of one opening in the casing 11, and the sleeve 4 A placement member 15 to be placed; closed end portions 12 and 13 for closing both end openings of the housing 11; an insertion device 20 for inserting the roller base body 7 housed in the housing 11 into the sleeve 4; A decompressor 31 that decompresses the inside of the housing 11 is provided.

  As shown in FIGS. 7 and 5, the casing 11, the closed end portions 12 and 13, the mounting member 15, the sealing member 17, and the insertion device 20 in the decompression device 30 are each a housing in the pressurizing device 10. The body 11, the closed end portions 12 and 13, the mounting member 15, the sealing member 17, and the insertion device 20 are basically configured in the same manner. The decompressor 31 only needs to be able to depressurize the inside of the casing 11 closed by the closed ends 12 and 13 to about 3 hPa, for example, a vacuum pump or the like is employed.

  As shown in FIG. 7, in the decompression method using the decompression device 30, the casing 11 and the closed ends 12 and 13 are assembled, and the sleeve 4 produced as described above is attached to the mounting member 15. The sleeve 4 is placed on a placement surface 16 and placed at a predetermined position. Next, both ends of the shaft body 2 in the roller base body 7 having the foamed elastic layer 3 coated with the fluid adhesive on the outer peripheral surface are fixed to the sandwiching members 23 and 24, and a pair of support shafts 21 and 22. The roller base 7 is sandwiched between the casing 11, the mounting member 15, the sleeve 4 supported by the mounting member 15 and the closed end 13, and the roller base 7 is inserted into the sleeve. 4, the pressure reducing device 30 is assembled by closing the casing 11 with the closed end 12.

  Next, the decompressor 31 is started, the inside of the decompression device 30 is decompressed to a predetermined pressure, and the foamed elastic layer 3 of the roller base 7 is decompressed in a predetermined decompression environment. Then, although the foamed elastic layer 3 initially has a higher pressure in the cell than in the reduced pressure environment, if the foamed elastic layer 3 is left in the predetermined reduced pressure environment for a while, the gas in the cell is gradually released from the foamed elastic layer 3. Therefore, the outer diameter of the sleeve 4 gradually decreases after being expanded, and becomes smaller than the inner diameter of the sleeve 4. At this time, the pressure in the decompression device 30 and the time during which the roller base body 7 is placed in the pressure environment may be such that the outer diameter of the foamed elastic layer 3 is smaller than the inner diameter of the sleeve 4. The pressure in the apparatus 10 is preferably adjusted to 3 to 100 hPa, particularly preferably adjusted to 5 to 80 hPa, and the time of being placed in the pressure environment is, for example, several seconds or more and 2 hours or less. It is preferable that it is several seconds or more and 1 hour or less. Under the pressure environment, the shrinkage rate in the radial direction of the foamed elastic layer 3 is, for example, a ratio of about 90 to 99% of the thickness (initial thickness) of the foamed elastic layer 3 at normal pressure. This is preferable in that it does not damage the foamed structure of the foamed elastic layer 3 and has excellent resilience when the decompression is released, and it is particularly preferably 95 to 99%.

  In this way, in a state where the outer diameter of the foamed elastic layer 3 is smaller than the inner diameter of the sleeve 4, the pair of support shafts 21 and 22 in the insertion device 20 are manually or automatically moved to the sleeve 4 side (in FIG. 7). As shown in FIG. 8, the roller base material 7 supported by the insertion device 20 is moved forward until the end 3 </ b> A of the foamed elastic layer 3 protrudes from the end of the sleeve 4. Insert inside. At this time, the holding member 24 of the insertion device 20 has an outer diameter smaller than the outer diameter of the foamed elastic layer 3, and the mounting member 15 is installed at the above-described position, and thus protrudes from the end of the sleeve 4. The end portion 3 </ b> A of the foamed elastic layer 3 and the clamping member 24 reach the space defined between the mounting member 15 and the closed end portion 13 via the inside of the sleeve 4. Since the length of the sleeve 4 in the axial direction is adjusted as described above, the end 3B of the foamed elastic layer 3 is not inserted into the sleeve 4 as shown in FIG. In this way, the roller base body 7 provided with the foamed elastic layer 3 in which an adhesive is applied to the outer peripheral surface as desired can be inserted into the sleeve 4.

  In the manufacturing method according to the present invention, the roller base body 7 is inserted into the sleeve 4 at room temperature or under heating, whether it is a pressure method or a pressure reduction method. When the curable material is applied to the outer peripheral surface of the foamed elastic layer 3 and the region where the sleeve 4 is provided, it is naturally heated below the curing temperature of the curable material. In consideration of operability and the like, the roller base body 7 is preferably inserted into the sleeve 4 at room temperature.

  In the manufacturing method according to the present invention, then, while maintaining the state in which the roller base body 7 in which the foamed elastic layer 3 is contracted is inserted into the sleeve 4, the pressurized state or the decompressed state in the pressure environment is released, If desired, the roller base material 7 inserted into the sleeve 4 is taken out from the pressurizing device 10 or the decompressing device 30 and is allowed to stand under atmospheric pressure. Then, the foamed elastic layer 3 having a reduced diameter smaller than the inner diameter of the sleeve 4 gradually expands or expands, and the outer peripheral surface of the foamed elastic layer 3 inserted into the sleeve 4 becomes the inner peripheral surface of the sleeve 4 (desired (Through the curable material applied by) and finally press-contact. The time for allowing the roller base material 7 inserted into the sleeve 4 to stand still is appropriately selected depending on the pressure in the pressure environment and the time in which the roller base material 7 is placed in the pressure environment. It is.

  In this way, the roller base body 7 can be inserted into the sleeve 4, and the both end portions 3 </ b> A and 3 </ b> B of the foamed elastic layer 3 can be protruded from the sleeve 4.

  In the manufacturing method according to the present invention, as shown in FIG. 9, a bottomed cylindrical end pressing member 9 is then provided on each of both ends 3 </ b> A and 3 </ b> B of the foamed elastic layer 3 protruding from the end of the sleeve 4. Is installed. The end pressing member 9 slightly reduces the diameters of both end portions 3A and 3B of the expanded foamed elastic layer, thereby ensuring workability when applying the adhesive forming the end adhesive layer 6 and the like. As shown in FIG. 9, the end pressing member 9 has a bottom portion having a through hole through which the shaft body 2 of the roller base body 7 passes, and an inner diameter slightly smaller than the outer diameter of the foamed elastic layer 3. And a bottomed cylindrical shape including a peripheral side surface protruding from the bottom. As shown in FIG. 9, the peripheral side surface of the end pressing member 9 is formed between the end portion of the sleeve 4 and the end portion of the peripheral side surface when the end pressing member 9 is mounted on both end portions 3 </ b> A and 3 </ b> B. It is adjusted to such a length that a gap is formed so that a curable material for forming the end adhesive layer 6 can be applied therebetween. The end pressing member 9 may be attached to the both end portions 3A and 3B automatically or manually.

In the manufacturing method according to the present invention, the outer peripheral surfaces of both end portions 3A and 3B of the foamed elastic layer 3 and the gap defined between the end portion of the sleeve 4 and the end portion of the peripheral side surface are Preferably, the curable substance is applied so as to be in contact with the end portion of the sleeve 4, and particularly preferably in contact with the end portion of the sleeve 4 so as to make a round in the circumferential direction. As a method for applying the curable substance, a dispenser method or the like can be applied in addition to the above-described method. When the curable substance is applied to the gap, the curable substance can be appropriately diluted with a diluent or the like. The coating amount of the curable substance may be adjusted so as to be equal to or less than the outer diameter of the sleeve 4. For example, in the case of a silicone composition, it is adjusted to about 0.001 to 0.016 g / cm ^2. The

  In the manufacturing method according to the present invention, the end adhesive layer 6 is then formed by curing the gap, that is, the curable material applied to the outer peripheral surfaces of both end portions 3A and 3B of the foamed elastic layer 3. . The conditions for curing the curable substance are selected according to the applied curable substance. For example, when the curable substance is a silicone-based adhesive, the heating temperature is 100 to 200 ° C., the heating time is 5 minutes or more 2 Curing conditions under time can be selected. When the end adhesive layer 6 is formed in this way, the produced end roller is mounted on the image forming apparatus, and the end roller formed is rotated even if the elastic roller is repeatedly rotated at high speed and stopped. The agent layer 6 can prevent the end of the sleeve 4 from peeling off. The apparatus for curing the curable substance may be an apparatus that can realize the curing conditions, and examples thereof include various heaters such as an oven, a blower dryer, and an infrared heater, and various dryers.

  In the manufacturing method according to the present invention, the end pressing members 9 attached to both end portions 3A and 3B of the foamed elastic layer 3 are then removed.

  In the manufacturing method according to the present invention, the adhesive existing between the foamed elastic layer 3 and the sleeve 4 is cured as desired. The conditions for curing the adhesive are selected according to the curing conditions of the applied adhesive. For example, when the adhesive is a silicone-based adhesive, the heating temperature is 100 to 200 ° C., the heating time is 5 minutes or more and 2 hours. The following curing conditions can be selected. When the adhesive is cured in this manner, the adhesive is uniformly interposed between the foamed elastic layer 3 and the sleeve 4, and the adhesive is also present in the surface of the foamed elastic layer 3 and in the cells near the surface. It can penetrate | invade and the foaming elastic layer 3 and the sleeve 4 can be adhere | attached firmly. The apparatus for curing the adhesive only needs to be an apparatus that can realize the curing conditions, and examples thereof include various heaters such as an oven, a blow dryer, and an infrared heater, and various dryers.

  In this way, the elastic rollers 1A and 1B can be manufactured. That is, according to the manufacturing method according to the present invention, it is possible to manufacture the elastic rollers 1A and 1B including the foamed elastic layer 3, the sleeve 4, the end adhesive layer 6, and the adhesive layer 5 as required. it can. As described above, the elastic rollers 1A and 1B (hereinafter collectively referred to as the elastic roller 1) are mounted on the fixing device of the image forming apparatus, so that the elastic roller 1 is formed of the foamed elastic layer 3. Even if the rotary drive is repeatedly driven at high speed from the surface and stopped, the end of the sleeve 4 can be prevented from being peeled off by the end adhesive layer 6. As a result, the elastic roller 1 according to the present invention can contribute to forming a high-quality image when mounted on the fixing device of the image forming apparatus, and the foamed elastic layer 3 and the end adhesive layer. Since the elastic roller 1 itself is excellent in durability, the possibility that the contacted body in the attached fixing device is destroyed is extremely small.

The rubber composition forming the foamed elastic layer 3 may be a composition containing rubber, a foaming agent or a hollow filler, and various additives as required. For example, a cell in an independent cell state is formed. Preferred examples include foamed silicone rubber-based compositions and foamed urethane rubber-based compositions. In particular, the foamed silicone rubber-based composition capable of forming a cell in an independent cell state is excellent in heat resistance, durability, resistance to residual strain, etc., and is suitable for a high-speed operation of an image forming apparatus. It is. As such a foamed silicone rubber composition, an addition reaction type foamed silicone rubber composition is particularly preferred. As a hollow filler, what is necessary is just a filler which can form a cell, for example after hardening | curing a rubber composition, For example, polyorganosiloxane type spherical powder is mentioned. The polyorganosiloxane spherical powder may be a spherical powder made of polyorganosiloxane, and examples thereof include silicone powder. More specifically, a silicone rubber powder having a structure in which linear dimethylpolysiloxane is crosslinked, and having a structure in which a siloxane bond is crosslinked in a three-dimensional network represented by (CH ₃ SiO _3/2 ) _n Examples thereof include a powder of silicone resin such as so-called polymethylsilsesquioxane, and a powder of coated silicone rubber in which the surface of the silicone rubber is coated with silicone resin or the like.

  The addition reaction type foamed silicone rubber composition contains a vinyl group-containing silicone raw rubber, a silica-based filler, a foaming agent, an addition reaction crosslinking agent, an addition reaction catalyst, and a reaction control agent. An organic peroxide crosslinking agent, a heat resistance improver, and various additives may be contained.

  Examples of the vinyl group-containing silicone raw rubber include millable silicone rubber and heat-crosslinked silicone rubber (HTV: High Temperature Vulcanizing). These vinyl group-containing silicone raw rubbers have the property that a foaming agent and an addition reaction cross-linking agent can be easily kneaded with a roll mill or the like in a later step, and are used alone or in combination of two or more. Can be used.

Examples of the silica-based filler include a fumed silica or a precipitated silica having a reinforcing property, and a surface having a high reinforcing effect that is surface-treated with a silane coupling agent represented by a general formula RSi (OR ′) _3. A treated silica-based filler is preferred. Here, R in the general formula is a glycidyl group, vinyl group, aminopropyl group, methacryloxy group, N-phenylaminopropyl group, mercapto group or the like, and R ′ in the general formula is a methyl group or an ethyl group. . The silane coupling agent represented by the general formula can be easily obtained, for example, as trade names “KBM1003” and “KBE402” manufactured by Shin-Etsu Chemical Co., Ltd. Such a silica-based filler surface-treated with a silane coupling agent can be obtained by treating the surface of the silica-based filler according to a conventional method. The compounding amount of the silica-based filler is preferably 5 to 100 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. A silica type filler can be used individually by 1 type or in mixture of 2 or more types.

  The foaming agent may be a foaming agent conventionally used for foamed rubber. Examples of the inorganic foaming agent include sodium bicarbonate and ammonium carbonate. Examples of the organic foaming agent include diazoamino derivatives, azonitrile derivatives, azo And organic azo compounds such as dicarboxylic acid derivatives. Usually, an inorganic foaming agent is used when forming continuous cells in rubber, and an organic foaming agent is used when forming independent cells. In the elastic roller 1, the foaming agent is preferably an organic foaming agent in that it can form a cell in an independent cell state. Specifically, for example, azodicarboxylic acid amide, azobis-isobutyrate is used. An azo compound such as ronitrile is preferably used. In particular, dimethyl-1,1'-azobis (1-cyclohexanecarboxylate) can be preferably used. The blending amount of the foaming agent varies depending on the type of the foaming agent, but it is preferable to adjust the Asker C hardness of the foamed elastic layer 3 to 20 to 60. Specifically, for example, it may be 0.1 to 10 parts by mass, particularly 0.5 to 10 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. If the blending amount of the foaming agent is less than 0.1 parts by mass, sufficient cells may not be formed in the foamed elastic layer 3 to be formed. On the other hand, if it exceeds 10 parts by mass, the foamed silicone rubber As a result, the mechanical strength of the foamed elastic layer 3 may be lowered. When dimethyl-1,1′-azo-bis (1-cyclohexanecarboxylate) is selected as the foaming agent, the blending amount is 0.5 to 5 with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. The mass part is particularly good. A foaming agent can be used individually by 1 type or in mixture of 2 or more types.

  As the addition reaction crosslinking agent, for example, a known organohydrogenpolysiloxane can be used as an addition reaction type crosslinking agent having two or more SiH groups (SiH bonds) in one molecule. The organohydrogenpolysiloxane may be linear, cyclic or branched. The compounding amount of the organohydrogenpolysiloxane is preferably 0.01 to 20 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. An addition reaction crosslinking agent can be used individually by 1 type or in mixture of 2 or more types.

  The addition reaction catalyst includes, for example, a simple substance of Group 9 or 10 of the periodic table and a compound thereof, and more specifically, particulate platinum adsorbed on a carrier such as silica, alumina, or silica gel. Metals, platinum chloride, chloroplatinic acid, chloroplatinic acid hexahydrate and olefin or divinyldimethylpolysiloxane complexes, platinum-based catalysts such as chloroplatinic acid hexahydrate alcohol solutions, palladium catalysts, rhodium catalysts, etc. Can be mentioned. The addition amount of these addition reaction catalysts is sufficient as the catalyst amount, and is usually 1 in terms of the total amount of addition reaction type foamed silicone rubber composition in terms of the metal amount of Group 9 or Group 10 of the Periodic Table. It is good that it is -1,000 ppm, and it is especially good that it is 10-500 ppm. If the amount of addition reaction catalyst is less than 1 ppm in terms of the metal content of Group 9 or Group 10 of the Periodic Table, the crosslinking reaction of vinyl group-containing silicone raw rubber does not proceed sufficiently, and vinyl group-containing silicone Curing of the raw rubber may be insufficient. On the other hand, if it exceeds 1,000 ppm, the ability to accelerate the crosslinking reaction of the vinyl group-containing silicone raw rubber is not improved, and the economic efficiency may be lowered. An addition reaction catalyst can be used individually by 1 type or in mixture of 2 or more types.

  As the reaction control agent, known reaction control agents can be used without limitation, and examples thereof include methylvinylcyclotetrasiloxane, acetylene alcohols, siloxane-modified acetylene alcohol, and hydroperoxide. The compounding amount of the reaction control agent is preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. The reaction control agents can be used alone or in combination of two or more.

  The organic peroxide cross-linking agent can be used alone to cross-link vinyl group-containing silicone raw rubber, but if used in combination as an auxiliary cross-linking agent for an addition reaction cross-linking agent, the physical properties of the silicone rubber, such as strength and strain, can be improved. improves. Examples of the organic peroxide crosslinking agent include benzoyl peroxide, bis-2,4-dichlorobenzoyl peroxide, dicumyl peroxide, di-t-butyl peroxide, and 2,5-dimethyl-2,5-bis. (T-butylperoxy) hexane and the like. The compounding amount of the organic peroxide crosslinking agent is preferably 0.3 to 10 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. An organic peroxide crosslinking agent can be used individually by 1 type or in mixture of 2 or more types.

  The heat resistance improver may be any compound that improves the heat resistance of the foamed elastic layer 3, and examples thereof include carbon black, iron oxide (also referred to as bengara), cerium oxide, and cerium hydroxide. These can be used individually by 1 type or in mixture of 2 or more types.

The carbon black can be generally classified into furnace black, channel black, acetylene black, thermal black, etc. depending on the production method. However, if the content of sulfur, amine, etc. is large, the addition reaction type foamed silicone rubber composition Since the addition reaction may be inhibited, carbon black having a low content of sulfur, amine, etc., for example, acetylene black is preferably used. Preferred examples of the iron oxide include black bengara (Fe ₃ O ₄ ) and red bengara (Fe ₂ O ₃ ). The cerium oxide and the cerium hydroxide may be used alone, but are used together with the carbon black and / or the iron oxide in that the change in hardness of the foamed elastic layer 3 can be suppressed. preferable.

  The total amount of the heat resistance improver is preferably 0.1 to 35 parts by mass, and particularly preferably 1 to 10 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. If the total blending amount of the heat resistance improver is within the above range, the blending amounts of carbon black, iron oxide, cerium oxide and cerium hydroxide are not particularly limited. For example, the compounding amount of the carbon black is preferably 0 to 15 parts by mass, more preferably 0.2 to 15 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. The mass part is particularly good. The blending amount of Bengala is preferably 0 to 30 parts by mass, more preferably 0.2 to 30 parts by mass, and 2 to 20 parts by mass with respect to 100 parts by mass of the vinyl group-containing silicone raw rubber. There is especially good. The blending amounts of cerium oxide and cerium hydroxide are preferably 0.1 to 5 parts by weight, particularly 0.2 to 2 parts by weight, based on 100 parts by weight of the vinyl group-containing silicone raw rubber. Good.

  The various additives include, for example, fillers such as calcium carbonate, colorants, flame retardant improvers, thermal conductivity improvers, release agents, alkoxy silanes, diphenyl silane diols, carbon functional silanes, Examples thereof include dispersants such as both-end silanol-blocked low-molecular siloxanes, and non-reinforcing silica such as pulverized quartz and diatomaceous earth that can adjust the hardness of the resulting rubber. These various additives are blended in a desired blending amount.

  As the silicone rubber composition containing the vinyl group-containing silicone raw rubber, the silica filler, and the various additives, for example, trade names “KE series” and “KEG series” manufactured by Shin-Etsu Chemical Co., Ltd. can be easily used. It can be obtained.

  The specific gravity of the rubber composition is not particularly limited, but since the specific gravity of the rubber composition also affects the density of the foamed elastic layer 3 to some extent, the specific gravity depends on the various rollers disposed in the image forming apparatus. Adjusted to The specific gravity of the rubber composition is usually preferably 1.00 to 2.00, more preferably 1.05 to 1.50.

  The rubber composition is, for example, several minutes to several hours, preferably 5 until it is uniformly mixed using a rubber kneader such as a two-roll, three-roll, roll mill, Banbury mixer, dough mixer (kneader) or the like. It is obtained by kneading at room temperature or under heating for 1 minute to 1 hour.

  The elastic roller 1 according to the present invention is not limited to the above-described embodiment, and various modifications can be made within a range in which the object of the present invention can be achieved. For example, in the elastic roller 1, the sleeve 4 is the outermost layer, but in the present invention, the sleeve does not have to be the outermost layer, and the sleeve may be formed at a position heated by the external heating means.

  In the elastic rollers 1A and 1B according to the present invention, the end adhesive layer 6 is not formed up to the end surface of the foamed elastic layer 3, but in this invention, the end adhesive layer is formed up to the end surface of the foamed elastic layer. Alternatively, it may be formed on the entire outer peripheral surface of both ends of the foamed elastic layer protruding from the sleeve.

  In the elastic rollers 1A and 1B according to the present invention, the end adhesive layer 6 is formed so as to be in contact with the end of the sleeve 4, but in this invention, the end of the sleeve and the end adhesive layer The end adhesive layer may be formed without contact with the end, that is, with an interval between the end of the sleeve and the end of the end adhesive layer.

  In the elastic rollers 1A and 1B according to the present invention, the adhesive layer 5 and the end adhesive layer 6 are independently formed. In the present invention, the adhesive layer and the end adhesive layer are integrally formed. It may be formed.

  In the elastic roller 1A according to the present invention, the end adhesive layer 6 has a uniform thickness, and in the elastic roller 1B according to the present invention, the end adhesive layer 6 has a thickness toward the end of the foamed elastic layer 3. In this invention, the elastic roller may be formed such that the thickness of the end adhesive layer gradually increases toward the end of the foamed elastic layer.

  Furthermore, in the present invention, the elastic roller may include a heating body, for example, an electric heater, a heating coil, or the like, between the shaft body, the elastic layer, or between the shaft body and the elastic layer, depending on the application. .

  In the present invention, other layers such as an elastic layer, a release layer, a coat layer, a surface layer, and / or a protective layer may be formed on the outer peripheral surface of the sleeve 4 as desired. The elastic layer is a layer for ensuring elasticity and may be formed of various rubbers, and examples of the rubber include silicone rubber, urethane rubber, and fluorine rubber. The thickness of the elastic layer is preferably 20 to 500 μm, particularly preferably 100 to 400 μm. Further, the release layer is a layer for ensuring the releasability of the developer, and may be formed of various resins, coupling agents, etc. Examples of the resin include fluorine resin, silicone resin, urethane resin, and the like. Examples of the coupling agent include silane coupling agents. The thickness of the release layer is preferably 15 to 200 μm, particularly preferably 20 to 50 μm. The coat layer, the surface layer, and the protective layer are usually formed on the outer peripheral surface of the sleeve 4 in a thickness of 1 to 100 μm according to a conventional method. The material for forming the coat layer, the surface layer, and the protective layer is not particularly limited, but the elastic roller 1 is preferably a material that is not easily permanently deformed because it is in contact with or pressed against the contacted body. For example, alkyd resins, phenol-modified / silicone-modified alkyd resin modified products, oil-free alkyd resins, acrylic resins, silicone resins, epoxy resins, fluororesins, phenol resins, polyamide resins, urethane resins, polyamideimide resins, and the like And the like. In the present invention, the sleeve 4 is formed of silicone rubber on the outer surface of the single-layered cylindrical body formed of the metal material or the single-layered cylindrical body formed of the metal material. The laminate is preferably a laminate in which an elastic layer and a release layer formed of a fluororesin are laminated in this order.

  The manufacturing method according to the present invention is not limited to the above-described manufacturing method, and various modifications can be made within a range in which the object of the present invention can be achieved. For example, in the manufacturing method according to the present invention, after the adhesive is applied to the outer peripheral surface of the foamed elastic layer 3 in the roller base material 7, the roller base material 7 is under a predetermined pressure environment. After the roller base is placed in a predetermined pressure environment, an adhesive may be applied to the outer peripheral surface of the foamed elastic layer in the roller base.

  Further, in the manufacturing method according to the present invention, an adhesive is applied to the outer peripheral surface of the foamed elastic layer 3 and the region where the sleeve 4 is provided as desired. In the present invention, the outer peripheral surface of the foamed elastic layer is used. In addition, an adhesive may be applied to the inner peripheral surface of the sleeve.

  Furthermore, in the manufacturing method according to the present invention, when an adhesive is applied to the outer peripheral surface of the foamed elastic layer 3 in the roller base body 7 in the region where the sleeve 4 is provided, if desired, You may harden simultaneously with the adhesive agent apply | coated to the outer peripheral surface of both ends 3A and 3B of the foaming elastic layer 3. FIG.

  Furthermore, in the manufacturing method according to the present invention, when an adhesive is applied to the outer peripheral surface of the foamed elastic layer 3 in the roller base body 7 in the region where the sleeve 4 is provided, if desired, first, the adhesive After the foamed elastic layer 3 and the sleeve 4 are bonded, the end pressing members 9 are attached to the both ends 3A and 3B of the foamed elastic layer 3 as described above, and the sleeve 4 and the end pressing member are mounted. You may harden the adhesive agent apply | coated to the gap | interval defined between the edge parts of 9 peripheral side surfaces.

  In the manufacturing method according to the present invention, the outer peripheral surface of the foamed elastic layer 3 and the region where the sleeve 4 is provided, and the outer peripheral surfaces of both end portions 3A and 3B of the foamed elastic layer 3 and the peripheral surface of the sleeve 4 and the peripheral surface. In this invention, the adhesive is applied in advance to the entire outer peripheral surface of the foamed elastic layer of the roller base material. May be.

  Further, in the manufacturing method according to the present invention, the roller base body 7 is inserted into the sleeve 4 in the pressure device 10 and the pressure device 30, and the sleeve 4 is disposed at a predetermined position of the foamed elastic layer 3. However, in this invention, after the roller base material is inserted into the sleeve in the pressure device and the pressure reduction device, the roller base material may be taken out from the pressure device and the pressure reduction device to adjust the position of the sleeve. .

  In the manufacturing method according to the present invention, the end pressing member 9 is attached to both ends 3A and 3B of the foamed elastic layer 3, and an adhesive is applied to both ends 3A and 3B. In this case, the adhesive may be applied to both ends of the foamed elastic layer without attaching the end pressing members.

  Each of the pressure device 10 and the pressure device 30 used in the manufacturing method according to the present invention is configured to house one roller base 7 and one sleeve 4 in series in the axial direction thereof. However, the pressurization device and the decompression device used in the present invention each accommodates a plurality of roller bases and a plurality of sleeves in series in the axial direction thereof and is inserted into the sleeves. You may be comprised so that the body can be formed in multiple numbers at once or continuously.

  The elastic roller 1 is disposed, for example, as the fixing roller 61 built in the image forming apparatus 40 shown in FIG. 10, more specifically, the fixing apparatus 60 of the image forming apparatus 40.

  As shown in FIG. 10, the image forming apparatus 40 according to the present invention includes a rotatable image carrier 41 on which an electrostatic latent image is formed, for example, a photosensitive member, and abuts or presses against the image carrier 41 or A charging unit 42 that charges the image carrier 41, for example, a charging roller, and an exposure unit 43 that is provided above the image carrier 41 and forms an electrostatic latent image on the image carrier 41; A developing unit 50 which is provided in contact with or pressure contact with the image carrier 41 or at a predetermined interval, supplies the developer 52 with a constant layer thickness to the image carrier 41, and develops the electrostatic latent image; The transfer means 44 is provided so as to be pressed against the lower side of the image carrier 41 and transfers the developed electrostatic latent image from the image carrier 41 to the recording body 46, for example, a transfer roller, and downstream in the conveying direction of the recording body 46. Developer 52 (transferred to the recording medium 46). A fixing device 60 for fixing the electrostatic latent image) and a cleaning means 45 for removing the developer 52 not transferred to the recording body 46 and remaining on the image carrier 41 and / or dust adhering to the image carrier 41. It consists of

  As shown in FIG. 10, the developing unit 50 has an opening at a position facing the image carrier 41, and is provided in the developer storage unit 51 that stores the developer 52 and the developer storage unit 51. Further, the stirrer 53 that uniformly stirs the developer 52 and the opening of the developer container 51 are provided in contact with or in pressure contact with the image carrier 41 or at a predetermined interval. A rotatable developer carrier 54 for supplying the developer 52 with a constant layer thickness, for example, a developing roller and a developer carrier 54 is provided above the developer carrier 54, and comes into contact with the developer carrier 54 to reduce the layer thickness of the developer 52. A developer regulating member 55 that regulates and charges the developer 52 by frictional charging, such as an elastic blade, is provided.

  As shown in FIG. 10, the fixing device 60 includes a fixing roller 61, a pressure roller 62 disposed opposite to the fixing roller 61, and a fixing roller in a housing 64 having an opening 65 through which the recording medium 46 passes. An external heating means 63 for heating 61 from the outside is provided, and the fixing roller 61 and the pressure roller 62 are rotatably supported so as to contact or press against each other. The pressure roller 62 is in contact with or in pressure contact with the fixing roller 61 by an urging means (not shown) such as a spring. The fixing device 60 is equipped with a heating coil as the external heating means 63 and employs an induction heating method. The heating coil as the external heating means 63 is a member having a length substantially the same as the axial length of the fixing roller 61, and is disposed substantially parallel to the fixing roller 61 at a certain interval from the surface of the fixing roller 61. Has been. Although not shown, this heating coil is usually made of a ferromagnetic material such as ferrite and is formed into I-type, E-type, U-type, etc., which are typical shapes used for a switching power source, and a conducting wire is wound. It is made up of. When a high-frequency alternating current is applied to the conducting wire of the heating coil 63, an eddy current is generated in the sleeve 4 and the sleeve 4 is induction-heated by the Joule heat. As a result, the fixing roller 61 is heated.

  In the fixing device 60, the external heating means adopts, in addition to the induction heating method, a radiant heating method using a halogen heater and a reflector, a direct contact heating method in which heating is performed by directly contacting a heater or the like. The position where the external heating means is arranged is not particularly limited. The fixing device 60 may employ an internal heating unit instead of the external heating unit or in addition to the external heating unit.

  The image forming apparatus 40 operates as follows. First, as shown by the arrow in FIG. 10, the image carrier 41 rotates in the clockwise direction, and after the developer 52 and / or dust on the surface is removed by the cleaning unit 45, the charging unit 42 removes the image carrier 41. Then, the image is exposed by the exposure means 43, and an electrostatic latent image is formed on the surface of the image carrier 41.

  On the other hand, in the developing means 50, the developer carrier 54 rotates in the direction of the arrow shown in FIG. 10, whereby the developer 52 is supplied to the developer carrier 54, and the supplied developer 52 is supplied to the developer carrier. Passing between 54 and the developer regulating member 55, it is regulated to a desired layer thickness and charged as desired.

  Next, a developer 52 having a desired layer thickness and charge amount is supplied to the image carrier 41 via the developer carrier 54, and the electrostatic latent image formed on the image carrier 41 is developed by the developer 52. This electrostatic latent image is visualized as a developer image. Next, the developer image developed on the image carrier 41 is transferred by the transfer unit 44 onto the recording body 46 conveyed between the image carrier 41 and the transfer unit 44. The recording body 46 to which the developer image has been transferred is conveyed to the fixing device 60 and heated when passing through a contact portion or a pressure contact portion between the pressure roller 62 and the fixing roller 61 heated by the heating coil 63. The developer image (electrostatic latent image) transferred by being pressed and / or pressed is fixed on the recording body 46 as a permanent image. In this way, an image can be formed on the recording body 46.

  Since the image forming apparatus 40 includes the elastic roller 1 as the fixing roller 61, the elastic roller 1, i.e., the fixing roller, even if the image forming apparatus or the fixing apparatus is repeatedly driven and stopped over a long period of time. Peeling between the foamed elastic layer 3 and the sleeve 4 at 61 can be effectively prevented, and as a result, a high-quality image can be formed over a long period of time.

  The image forming apparatus 40 is an electrophotographic image forming apparatus. However, in the present invention, the image forming apparatus is not limited to the electrophotographic system, and may be, for example, an electrostatic image forming apparatus. Good. Further, the image forming apparatus is a monochrome image forming apparatus in which only a single color developer is accommodated in the developing unit. However, in the present invention, the image forming apparatus is not limited to the monochrome image forming apparatus, and is a color image forming apparatus. It may be. Examples of the color image forming apparatus include a four-cycle color image forming apparatus that sequentially repeats primary transfer of a developer image carried on an image carrier to an intermediate transfer body, and a plurality of image carriers provided with developing means for each color. Examples thereof include a tandem type color image forming apparatus in which a body is arranged in series on an intermediate transfer body or a transfer conveyance belt. The image forming apparatus is, for example, an image forming apparatus such as a copying machine, a facsimile, or a printer.

(Example 1)
First, the shaft body 2 (diameter 12 mm × length 350 mm, SUM22) subjected to electroless nickel plating was washed with toluene, and a primer “No. 101A / B” (manufactured by Shin-Etsu Chemical Co., Ltd .: trade name) was used. Applied. The primer-treated shaft was fired at 180 ° C. for 30 minutes using a gear oven, and then cooled at room temperature for 30 minutes or more to form a primer layer.

  On the other hand, a silicone rubber composition “KE-904FU” (manufactured by Shin-Etsu Chemical Co., Ltd .: trade name) containing a vinyl group-containing silicone raw rubber and a silica-based filler, and an addition reaction crosslinking agent “C-153A” ( Shin-Etsu Chemical Co., Ltd .: trade name) 2.0 parts by mass, foaming agent azobis-isobutyronitrile “KEP-13” (Shin-Etsu Chemical Co., Ltd .: trade name) 2.5 parts by mass, and addition reaction An appropriate amount of platinum catalyst as a catalyst, 0.5 parts by mass of a reaction control agent “R-153A” (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), and an organic peroxide cross-linking agent “C-3” (Shin-Etsu Chemical Co., Ltd.) Company: product name) Appropriate amount of heat resistance improver "KEP-12" (manufactured by Shin-Etsu Chemical Co., Ltd .: product name) 1.0 part by mass sufficiently with two rolls, addition reaction type A foamed silicone rubber composition was prepared.

  Next, the shaft body 2 on which the primer layer is formed and the addition reaction type foamed silicone rubber composition are integrally extracted by an extruder, and then the addition reaction type foamed silicone is used by using an infrared heating furnace (IR furnace). The rubber composition was heated at 250 ° C. for 10 minutes to be foam-crosslinked, and the addition reaction type foamed silicone rubber composition was foam-crosslinked. Then, the addition reaction type | mold foaming silicone rubber composition after foaming bridge | crosslinking was further heated for 7 hours at 200 degreeC using the gear oven, and was left to stand at normal temperature for 1 hour. Next, the outer diameter of the formed elastic elastic layer 3 was adjusted to 29.1 mm with a cylindrical grinder. In this way, a roller base body 7 provided with the foamed elastic layer 3 was produced. The length of the foamed elastic layer 3 in the axial direction is 340 mm, the average cell diameter in the cells existing in the foamed elastic layer 3 is 400 μm, the average width of the cell wall is 0.15 mm, and the foaming rate of the foamed elastic layer 3 is It was 310%. The Asker C hardness of the foamed elastic layer 3 was 40.

  On the other hand, the pressurizing apparatus 10 shown in FIG. 5 was prepared. The casing 11, the closed end portions 12 and 13, the mounting member 15, the support shafts 21 and 22, and the sandwiching members 23 and 24 were each formed of S45C, and the sealing member 17 was formed of nitrile rubber. The casing 11 has an outer diameter of 55 mm, an inner diameter of 50 mm, and a length of 2200 mm. The closed end portion 12 has an outer diameter of 55 mm, an inner diameter of 50 mm, and a length of 1.5 mm. The closed end portion 13 has an outer diameter of 55 mm, an inner diameter of 10 mm, and a length. It was 30 mm. Further, a sleeve (made of stainless steel (SUS304), thickness 40 μm, inner diameter 29.0 mm, axial length 330 mm, tensile strength 950 MPa) was prepared.

Next, an adhesive (trade name “KE-1831”, viscosity (25 ° C.) 200 Pa · s, Shin-Etsu Chemical Co., Ltd.) is applied to the outer peripheral surface of the foamed elastic layer 3 in the produced roller base body 7 and provided with the sleeve 4. Co., Ltd.) was applied uniformly with a roll coater without diluting with a solvent so that the coating amount was 0.025 g / cm ² (the thickness of the adhesive layer after curing was 10 μm). The heat resistance of this adhesive was 150 ° C., and the tensile shear bond strength in the cured product of the fluid adhesive was 1.0 MPa.

  Next, as shown in FIG. 5, the pressurizing device 10 was assembled, and the sleeve 4 was placed on the placement surface 16 of the placement member 15. Furthermore, both ends of the shaft body 2 in the roller base body 7 provided with the foamed elastic layer 3 coated with an adhesive are fixed to the clamping members 23 and 24, and the roller base body 7 is supported by a pair of support shafts 21 and 22. And the roller base 7 is arranged in the casing 11 in series in the upstream direction of the sleeve 4, the casing 11 is closed by the closed end 12, and the pressure device 10 is assembled in an airtight state. It was. Next, the pressurizer 14 was started to pressurize the pressurizer 10 so that the pressure in the pressurizer 10 reached 0.3 MPa. This pressure was maintained for 1 minute, and the foamed elastic layer 3 was pressurized and compressed to be smaller than the inner diameter of the sleeve 4. At this time, the shrinkage percentage of the foamed elastic layer 3 was about 91%. In a state where the foamed elastic layer 3 is compressed, the pair of support shafts 21 and 22 of the insertion device 20 are manually advanced to the sleeve 4 side, and the roller raw material supported by the insertion device 20 as shown in FIG. The body 7 was inserted into the sleeve 4, and a region in the foamed elastic layer 3 near the end 3 </ b> A (length in the axial direction was about 5 mm) was protruded from the sleeve 4. At this time, the length in the axial direction of the region near the other end 3B of the foamed elastic layer 3 was about 5 mm.

Next, the pressure in the pressure device 10 is released, the roller base body 7 inserted into the sleeve 4 is taken out from the pressure device 10, and both ends 3 A and 3 B of the foamed elastic layer 3 are respectively shown in FIG. A bottomed cylindrical end pressing member 9 (made of stainless steel, the inner diameter of the peripheral side surface is 29.0 mm, the length is 1.5 mm) was attached. Next, a gap (a length in the axial direction) defined on the outer peripheral surfaces of both end portions 3A and 3B of the foamed elastic layer 3 between the end portion of the sleeve 4 and the end portion of the peripheral side surface of the end pressing member 9. The adhesive (trade name “KE-441”, viscosity (25 mm) is in contact with the end of the sleeve 4 at a length (width) of about 1 mm in the circumferential direction. ° C) 15 Pa · s, manufactured by Shin-Etsu Chemical Co., Ltd.), with a dispenser method without diluting with a solvent, a coating amount of 0.004 g / cm ² (the thickness of the end adhesive layer 6 after curing is 38 μm) It applied uniformly so that it might become.

  In this way, the roller base material 7 in which the adhesive is applied in the vicinity of both end portions 3A and 3B of the foamed elastic layer 3 is removed by using a dryer (trade name “HIGH TEMPRATOR CHAMBER”, manufactured by Enomoto Co., Ltd.). The adhesive agent existing between the foamed elastic layer 3 and the sleeve 4 and the adhesive agent applied to the gap were cured by heating to 0 ° C. for 0.5 hour. Next, the end pressing members 9 attached to both end portions 3A and 3B of the foamed elastic layer 3 were removed, and the elastic roller of Example 1 was manufactured.

(Comparative Example 1)
An elastic roller of Comparative Example 1 was manufactured in the same manner as in Example 1 except that no adhesive was applied to the gap, that is, both end portions 3A and 3B of the foamed elastic layer 3.

  The elastic rollers of Example 1 and Comparative Example 1 manufactured in this way were each mounted on the durability tester shown in FIG. 11, and cracks in the foamed elastic layer 3, both ends of the sleeve 4 and the foamed elastic layer 3. The peeling situation was evaluated. This durability test apparatus 70 is fixed to the lower surface inside the casing, and includes a heating roller 71 provided with an internal heater 72, and external heaters 73 provided on both sides of the heating roller 71 along the axial direction. A test roller mounting portion 74 provided on the upper surface inside the housing so as to be movable up and down so as to face the heating roller 71, and a pressing force adjusting means 75 capable of moving the test roller mounting portion 74 up and down, for example, pressure adjustment A micrometer. As the heating roller 71, a metal (stainless steel (SUS304)) roller having a diameter of 20 mm was used.

  Each elastic roller of Example 1 and Comparative Example 1 is mounted as an elastic roller 76 on the bearing of the test roller mounting portion 74, and the elastic force mounted by operating the pressing force adjusting means 75 as shown in FIG. The roller 76 is pressed against the heating roller 71, and the elastic roller 76 is fixed at the press-contact portion between the heating roller 71 and the elastic roller 76 so that the foamed elastic layer 3 in the elastic roller 76 is recessed 3 mm inside (that is, elastic). The distance d between the central axis of the elastic roller 76 and the central axis of the heating roller 71 was adjusted so as to be 3 mm shorter than the sum of the outer diameter of the roller 76 and the heating roller 71).

  Next, the external heater 73 and the internal heater 72 were started, and the surface temperature of the heating roller 71 was adjusted to 180 ° C. Thereafter, the driving means (not shown) provided in the test roller mounting portion 74 is continuously operated at a rotational speed of 130 rpm for 100 hours, and after the recessed state of the foamed elastic layer 3 in the elastic roller 76 is released, the elastic roller 76 is moved to room temperature. Left for 24 hours.

  As a result, the elastic roller of Example 1 was continuously operated for 100 hours in the same manner after the test, but the foamed structure of the foamed elastic layer 3 was not peeled off from the foamed elastic layer 3 at both ends of the sleeve 4. Was confirmed to be excellent in durability without being damaged or damaged. Therefore, even when this elastic roller is mounted on the fixing device of the image forming apparatus as a fixing roller for a considerably long period of time, the possibility of destroying the contacted body such as the endless belt and the pressure roller is extremely small. In addition, it was expected that high quality images could be formed over a long period of time. On the other hand, after the test, the elastic roller of Comparative Example 1 was peeled off slightly from the foamed elastic layer 3 at the time when the sleeve 4 was continuously operated for 55 hours in the same manner. It was confirmed that the durability was inferior to that of the elastic roller. Therefore, when the elastic roller is mounted on the fixing device of the image forming apparatus as a fixing roller for a considerably long period of time, there is a high possibility that the contacted body such as the endless belt and the pressure roller will be destroyed, and It was expected that high quality images could not be formed.

FIG. 1 is a schematic perspective view showing an embodiment of an elastic roller according to the present invention. FIG. 2 is a schematic sectional view showing an embodiment of the elastic roller according to the present invention. FIG. 3 is a schematic sectional view showing another embodiment of the elastic roller according to the present invention. FIG. 4 is a schematic perspective view showing an embodiment of the roller original. FIG. 5 is a schematic explanatory view for explaining a state in which the roller base and the sleeve are housed in the pressure device. FIG. 6 is a schematic explanatory view for explaining a state in which the roller original body is inserted into the sleeve in the pressure device. FIG. 7 is a schematic explanatory view for explaining a state in which the roller base and the sleeve are stored in the decompression device. FIG. 8 is a schematic explanatory view for explaining a state in which the roller base is inserted into the sleeve in the decompression device. FIG. 9 is a schematic cross-sectional view showing a state in which end pressing members are attached to both ends of the foamed elastic layer in the roller base inserted into the sleeve. FIG. 10 is a schematic explanatory view showing an embodiment of the image forming apparatus according to the present invention. FIG. 11 is a schematic diagram showing a durability test apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Elastic roller 2 Shaft body 3 Foaming elastic layer 4 Sleeve 5 Adhesive layer 6 End adhesive layer 7 Roller base 9 End pressing member 10 Pressurizing device 11 Housing 12, 13 Closed end 14 Pressing machine 15 Mounted Member 16 Mounting surface 17 Sealing member 20 Insertion device 21, 22 Support shaft 23, 24 Holding member 30 Pressure reducing device 31 Pressure reducing device

40 Image forming apparatus 41 Image carrier 42 Charging means 43
44 Transfer means 45 Cleaning means 46 Recording body 50 Developing means 51 Developer accommodating portion 52 Developer 53 Stirrer 54 Developer carrier 55 Developer regulating member 60 Fixing device 61 Fixing roller 62 Pressure roller 63 External heating means 64 Housing 65 Opening 70 Durability test device 71 Heating roller 72 Internal heater 73 External heater 74 Test roller mounting part 75 Pressure adjusting means

Claims (5)

A foamed elastic layer formed on the outer peripheral surface of the shaft body, a metal sleeve provided on the outer peripheral surface of the foamed elastic layer so that both end portions of the foamed elastic layer protrude in the axial direction, and the sleeve And an end adhesive layer formed on the outer peripheral surface of the both ends of the foamed elastic layer protruding from the sleeve so as to contact the end of the sleeve. A fixing roller characterized by that. The fixing roller according to claim 1, further comprising an adhesive layer between the foamed elastic layer and the sleeve. The fixing roller according to claim 1, wherein the end adhesive layer has an outer diameter that gradually decreases toward the end. A fixing device comprising the fixing roller according to claim 1. An image forming apparatus comprising the fixing roller according to claim 1.

Images