JP2011186317A - Fixing device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fixing device capable of satisfactorily recovering a residual foamy fixing liquid that has not been used for fixing, in a constitution in which fine particles of resin are softened by the foamy fixing liquid and fixed to a recording medium, and to provide an image forming apparatus. <P>SOLUTION: The fixing device includes a fixing liquid recovery device 200 that recovers the residual foamy fixing liquid Fb remaining on an application roller 61 without being applied to transfer paper P. The fixing liquid recovery device 200 includes: a residual foamy fixing liquid storing portion 216 for storing the residual foamy fixing liquid Fb; and a fixing liquid recovery pump and fixing liquid recovery bottle 220 for vacuuming the residual foamy fixing liquid storing portion 216, thereby liquefying and recovering the residual foamy fixing liquid Fb. The residual foamy fixing liquid Fb is liquefied by vacuuming the inside of the residual foamy fixing liquid storing portion 216 by driving the suction pump 215. The liquefied residual foamy fixing liquid Fb is transferred and recovered into the fixing liquid recovery bottle 220 by the fixing liquid recovery pump. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fixing device used in an image forming apparatus such as a copying machine, a facsimile machine, and a printer. More specifically, the present invention relates to a fixing liquid that dissolves or swells resin fine particles such as toner and applies the resin fine particles on a recording medium. BACKGROUND OF THE INVENTION 1. Field of the Invention

  2. Description of the Related Art In recent years, so-called electrophotographic image forming apparatuses using toner have become mainstream as image forming apparatuses that form images on transfer paper as a recording medium, such as copying machines, printers, and facsimiles. 2. Description of the Related Art An electrophotographic image forming apparatus is widely used in offices and the like because it can easily create color images at high speed and high density using plain paper.

  2. Description of the Related Art In an electrophotographic image forming apparatus, a heat fixing type fixing device that fixes an unfixed toner image formed on a transfer paper onto the transfer paper using heat is often used. In a heat fixing type fixing device, a roller or a film is heated by a heating element such as a halogen heater or a ceramic heater, and a transfer paper on which unfixed toner is placed is sandwiched between pressure rollers and heated and pressed to melt and deform the toner. And anchored in the fiber of the transfer paper. Thermal fixing type fixing devices are widely used because of their excellent uniformity and stability, but on the other hand, they require a lot of energy to heat using a heating element and have a drawback of high energy consumption. is there.

  On the other hand, as a fixing method that can save energy compared to a heat fixing method that consumes a large amount of power for heat treatment, at least a part of the resin component of the toner is dissolved or swollen without heating to fix the toner. There is known a wet fixing method in which a fixing solution containing a softening agent that softens toner is applied to a toner image on the surface of a transfer paper to fix the toner image (for example, see Patent Document 1).

  The fixing device described in Patent Document 1 applies a fixing liquid to unfixed toner by pressing an application roller carrying a liquid fixing liquid on the surface against a transfer paper carrying unfixed toner. However, when the fixing liquid is supplied to the unfixed toner on the transfer paper as in Patent Document 1, the fixing roller remains on the surface of the application roller after passing through the application position where the application roller applies the fixing liquid to the transfer paper. A part of the unfixed toner is transferred into the liquid, and the toner image on the transfer paper is deteriorated. This is because the unfixed toner on the transfer paper is carried on the transfer paper by electrostatic force, so that the force carried by the electrostatic force is significantly reduced when the liquid touches, and the unfixed toner diffuses into the fixing liquid. This occurs because a part of the fixing liquid in which the unfixed toner is diffused in the liquid remains on the coating roller.

  Further, in a configuration in which a fixing liquid is supplied to toner on a toner image carrier such as an intermediate transfer belt, and then a toner image in which a resin on the toner image carrier is softened is transferred to transfer paper, the fixing liquid is applied using an application roller. There is also known a fixing device configured to apply to toner on a toner image carrier (see, for example, Patent Document 2). Also in the fixing device described in Patent Document 2, as in Patent Document 1, a part of unfixed toner is transferred to the remaining fixing liquid, and the toner image on the transfer paper is deteriorated. .

  Therefore, as a fixing device that can suppress a problem that a part of unfixed toner adheres to the application roller, the fixing solution is a foam-like fixing solution in which bubbles are dispersed in the solution. As in the case of the fixing liquid, a coating liquid that is applied to unfixed toner on transfer paper by an application roller is known (see, for example, Patent Document 3). In the fixing device of Patent Document 3, since a large amount of air exists in the bubbles of the fixing solution by making the fixing solution foam, the force for diffusing unfixed toner into the fixing solution becomes difficult to work on the transfer paper. The toner is fixed on the spot by the action of the fixing liquid without moving from the transfer paper even when the fixing liquid is applied. For this reason, the problem that a part of unfixed toner adheres to the application roller can be suppressed, and a better image can be obtained as compared with the configuration in which the liquid fixing liquid is applied to the transfer paper.

  Here, as in the fixing device described in Patent Document 3, in the configuration in which the foamy fixing solution is applied to the recording medium using the coating member, the coating member after the foaming fixing solution is applied to the recording medium is cleaned. It is desirable to provide an application member cleaning means. This is because the remaining foamy fixing solution remaining on the recording medium without being applied to the recording medium adheres to the coating member after passing through the coating position where the foamy fixing solution is applied to the recording medium. It is for recovering.

  Since the residual foam-fixing solution is supplied as a foam-fixing solution to the coating member, time has passed and a mechanical force is applied at the coating position, so a part of the foam is defoamed. For example, the state of the bubbles is changed compared to the state supplied to the application member. For this reason, when a new foamy fixing solution is supplied to the coating member in a state where the changed residual foamy fixing solution remains on the surface of the coating member, the residual foamy fixing solution and the new foamy fixing solution And the foam film becomes uneven, or when a new foam-like fixing liquid is supplied and applied to the recording medium in a state where the toner offset at the time of abnormality remains on the surface of the application member. The offset toner is retransferred to the recording medium, and the image may be deteriorated.

  For these reasons, when the foam fixing solution is applied to the recording medium using an application member, the foam fixing solution applied to the recording medium becomes uneven or the offset toner is re-applied to the recording medium. In order to prevent the image from being transferred, it is desirable to provide an application member cleaning unit to remove the residual foamy fixing solution.

  However, the foamy fixing solution removed by the application member cleaning means is in a bulky state. Since the volume of the fixer is swelled several tens of times that of the non-foamed fixer due to the foam, it is necessary to have a large recovery tank if the fixer is to be stored in the form of foam. turn into. Note that the foam-like fixing solution naturally defoams over time and the volume gradually decreases. However, since it takes a long time to defoam naturally, it is collected from the coating member in order to support continuous printing. Since it is necessary to contain the foamy fixing solution before defoaming, it is inevitable to use a large tank. If a large tank capable of storing such a foam-like fixing solution is arranged in the image forming apparatus, there is a problem that the apparatus is increased in size.

  For this reason, the residual foamy fixing solution is required to be liquefied and recovered. The following methods are known as methods for liquefying a foamy liquid.

  For example, a technique is known in which a foamed liquid is heated by a heating member, and the foamed liquid is broken by heat to be liquefied (see, for example, Patent Document 4).

  Further, a method is known in which the foamed liquid is sucked into a mesh or porous body having a continuous foam structure, and the foamed liquid is broken and liquefied by passing through micropores constituting the porous body (for example, , See Patent Document 5).

  As another method, a method is known in which the foamed liquid is defoamed and recovered by bringing the foamed liquid into contact with an antifoaming agent (see, for example, Patent Document 6).

  However, in the method of Patent Document 4, there is a concern that the use of heat causes the apparatus to be filled with steam, causing problems in the system. In addition, the use of heat can adversely affect the foam created upstream of the system, which can prevent stable fixation.

  Further, the method of Patent Document 5 has a problem that if there is a portion where the foam liquid is not filled in the mesh or the pores, a suction escape path is formed and the foam liquid is not sucked at all.

  Moreover, in the method of patent document 6, since the defoaming effect of an antifoamer is limited, there exists a problem that replenishment of an antifoamer is needed when the defoaming effect is lose | eliminated. Furthermore, since it is necessary to collect | recover the antifoamer which lost the defoaming effect in addition to the defoamed foamy liquid, there exists a problem that the quantity of collection | recovery will increase very much.

  Such a problem is not limited to toner particles that form a toner image on a recording medium as a resin, but in any case where a foamy fixing solution is applied to resin fine particles on a recording medium and the coating member is cleaned. Can also occur. Furthermore, the configuration is not limited to the configuration in which the coating member is cleaned, and the configuration is such that the foamy fixing solution that needs to be collected in the fixing device, such as a pressure member that contacts the coating member at the coating position, is recovered as the recovered foamy fixing solution. If so, the same problem will occur.

  The present invention has been made to solve such a problem, and in a configuration in which resin fine particles are softened using a foam fixing solution and fixed on a recording medium, a residual foam fixing solution that has not contributed to fixing is used. It is an object of the present invention to provide a fixing device that can be recovered satisfactorily and an image forming apparatus including the same.

  In the fixing device according to the present invention, bubbles are dispersed in a fixing solution containing a softening agent that softens resin fine particles containing the resin by dissolving or swelling at least a part of the resin to generate a foam-like fixing solution. A fixing liquid foaming means; and a foaming fixing liquid applying means for applying the foamy fixing liquid to a recording medium having a resin fine particle layer formed of the resin fine particles formed on a surface thereof. In the fixing device for softening the resin fine particles by applying the foamy fixing solution to the recording medium by means, and fixing it to the recording medium, it remains in the foamy fixing solution applying means without being applied to the recording medium. And a foam fixing solution collecting means for collecting the residual foam fixing solution, wherein the foam fixing solution collecting means comprises a residual foam fixing solution containing portion for containing the residual foam fixing solution, and the residual foam fixing. Depressurize the liquid container before The residual foamed fixer and liquefied recovery means for liquefying and recovering, by having been characterized.

  With this configuration, by reducing the pressure of the residual foam-fixing solution in the residual foam-fixing solution container, the residual foam-fixing solution is easy because the thickness of the liquid film becomes extremely thin as the foam volume increases. It breaks and liquefies, and the volume decreases. Therefore, in the configuration in which the resin fine particles are softened by using the foam fixing solution and fixed on the recording medium, the residual foam fixing solution that has not contributed to fixing can be recovered well.

  Further, in the fixing device according to the present invention, the residual foam-like fixer storage portion forms an opening for receiving the residual foam-like fixer from the foam-like fixer application means when opened, and the recovered foam when closed. And an openable / closable member for hermetically sealing the fixing solution container.

  With this configuration, an opening for receiving the residual foam-like fixing liquid can be formed in the residual foam-like fixing liquid container by opening the opening / closing member, and a residual foam-like fixing liquid container can be formed by closing the opening / closing member. Can be sealed in preparation for decompression, so that a member for forming an opening in the residual foam-like fixer accommodating portion and a member for sealing the residual foam-like fixer accommodating portion separately for decompression are provided. This eliminates the need to reduce the number of components, reduce the size of the device, reduce costs, and reduce the failure rate.

  Further, in the fixing device according to the present invention, the foamy fixing solution applying unit rotates in synchronization with the movement of the recording medium, and the foaming fixing solution supplied to the surface is applied to the recording medium. And a coating member cleaning unit that removes the residual foamy fixing solution from the surface of the coating member after passing through the coating position. The residual foam-like fixing liquid removed by the applying member cleaning means is collected.

  With this configuration, the foamy fixing solution recovery unit removes the residual foamy fixing solution from the surface of the coating member after passing through the coating position by the coating member cleaning unit. The residual foam fixer can be recovered satisfactorily without adversely affecting the application of the foam fixer.

  Further, in the fixing device according to the present invention, the application member cleaning unit includes a cleaning member that is formed of an elastic body and that contacts the surface of the application member and removes the residual foamy fixing liquid from the surface of the application member. It is characterized by that.

  With this configuration, the cleaning member made of an elastic body elastically contacts the surface of the coating member, so that the residual foamy fixing liquid can be removed from the surface of the coating member without damaging the coating member. Since the required positioning accuracy of the relative position between the cleaning member and the application member can be relaxed, the assembly process of the apparatus can be facilitated.

Further, an image forming apparatus according to the present invention includes a toner image forming unit that forms a toner image on a recording medium based on image information using a toner including resin fine particles containing a resin and a colorant.
An image forming apparatus comprising: a fixing unit that applies a foamy fixing solution to a surface of a recording medium on which a toner image is formed by the toner image forming unit, and fixes the toner image on the recording medium. The fixing unit includes the above-described fixing device.

  With this configuration, in the image forming apparatus provided with the above-described fixing device, the residual foam-like fixing solution is liquefied, and the resin fine particles are softened using the foam-like fixing solution and fixed on the recording medium. The residual foamy fixing solution that has not been obtained can be recovered well.

  According to the present invention, in a configuration in which resin fine particles are softened using a foam fixing solution and fixed on a recording medium, a fixing device and an image that can satisfactorily collect residual foam fixing solution that has not contributed to fixing. A forming apparatus can be provided.

1 is a schematic configuration diagram of an image forming apparatus including a fixing device according to an embodiment of the present invention. 1 is a partially enlarged configuration diagram illustrating a part of a printer unit of an image forming apparatus according to an embodiment in an enlarged manner. FIG. 3 is a partially enlarged view showing one of four image forming units of the image forming apparatus according to the embodiment. 1 is a configuration diagram schematically illustrating a fixing device according to an embodiment of the present invention. FIG. 5 is an enlarged view showing the operation of the fixing liquid recovery device of the fixing device according to the embodiment, and shows a state in which the residual foam-like fixing liquid is accommodated by opening the shutter of the residual foam-like fixing liquid accommodation unit. is there. FIG. 5 is an enlarged view showing the operation of the fixing liquid recovery device of the fixing device according to the embodiment, and is a view showing a state where the shutter of the residual foamy fixing liquid storage unit is closed. FIG. 4 is an enlarged view showing the operation of the fixing solution recovery device of the fixing device according to the embodiment, and is a view showing a state in which the inside of the residual foamy fixing solution container is decompressed. FIG. 5 is an enlarged view showing the operation of the fixing liquid recovery device of the fixing device according to the embodiment, and is a view showing a state in which the liquefied residual foamy fixing liquid is recovered in the fixing liquid recovery bottle. FIG. 9 is a configuration diagram schematically illustrating a modification of the fixing device according to the embodiment.

  Hereinafter, a case where the present invention is applied to a copying machine (hereinafter referred to as a copying machine 100) that is an image forming apparatus that forms an image by an electrophotographic method will be described as an example. In the present embodiment, a configuration in which the image forming apparatus having the fixing device of the present invention is a copying machine will be described, but other image forming apparatuses such as a printer and a facsimile may be used.

  First, the basic configuration of the copying machine 100 will be described. FIG. 1 is a schematic configuration diagram showing a copying machine 100 according to the present embodiment. The copying machine 100 includes a printer unit 1, a paper feeding device 40, and a document conveyance reading unit 50. The document conveyance reading unit 50 includes a scanner unit 150 that is a document reading device fixed on the printer unit 1 and an ADF 51 that is a document conveyance device supported by the scanner unit 150.

  The paper feeding device 40 separates the feeding roller 43 that feeds the transfer paper P from two paper feeding cassettes 42 arranged in multiple stages in the paper bank 41, and the fed transfer paper P, and supplies it to the paper feeding path 44. A separating roller 45 is provided. Further, a plurality of transport rollers 46 for transporting the transfer paper P to the paper transport path 37 of the printer unit 1 are also provided. The paper feed device 40 feeds the transfer paper P in the paper feed cassette 42 into the paper transport path 37 in the printer unit 1.

  The scanner unit 150 fixed on the printer unit 1 has a fixed reading unit 151 and a moving reading unit 152 as reading means for reading an image of the document MS. A fixed reading unit 151 having a light source, a reflection mirror, an image reading sensor such as a CCD, etc. is disposed immediately below a first contact glass (not shown) fixed to the upper wall of the casing of the scanner unit 150 so as to contact the original MS. ing. When the document MS conveyed by the ADF 51 passes over the first contact glass, the image reading sensor 153 receives the light from the light source through the plurality of reflection mirrors while sequentially reflecting the light emitted from the light source on the document surface. . Thereby, the document MS is scanned without moving the optical system including the light source and the reflection mirror.

  On the other hand, the moving reading unit 152 is disposed directly below a second contact glass (not shown) fixed to the upper wall of the casing of the scanner unit 150 so as to come into contact with the document MS, and is arranged on the right side of the fixed reading unit 151 in the drawing. Therefore, an optical system including a light source, a reflection mirror, and the like can be moved in the left-right direction in the drawing. Then, in the process of moving the optical system from the left side to the right side in the figure, the light emitted from the light source is reflected by a document (not shown) placed on the second contact glass and then passed through a plurality of reflecting mirrors. The light is received by an image reading sensor 153 fixed to the scanner body. Thereby, the original MS is scanned while moving the optical system. In this way, the scanner unit 150 scans the document MS and, based on the image information obtained by the image reading sensor 153, the optical writing device 2 drives the light source, as will be described later, to form four drum-shaped photoconductors. 4 (K, Y, M, C) is irradiated with laser light L.

  FIG. 2 is a partially enlarged configuration diagram illustrating a part of the internal configuration of the printer unit 1 in an enlarged manner. The printer unit 1 includes an optical writing device 2, four image forming units 3 (K, Y, M, and C) that form toner images of respective colors K, Y, M, and C, a transfer unit 90, and a paper transport unit 28. , A registration roller pair 33, a fixing device 60, and the like. Then, a light source such as a laser diode or LED (not shown) disposed in the optical writing device 2 is driven, and laser light L is directed toward the four drum-shaped photosensitive members 4 (K, Y, M, C). Irradiate. By this irradiation, an electrostatic latent image is formed on the surface of the photosensitive member 4 (K, Y, M, C) as a latent image carrier, and this latent image is developed into a toner image through a predetermined development process. The Note that the subscripts K, Y, M, and C added after the reference sign indicate specifications for black, yellow, magenta, and cyan. The toner corresponding to each color is made of a resin material colored in each color, and these resin materials are dissolved or swollen by a fixing solution of the fixing device 60 described later.

  Each of the image forming units 3 (K, Y, M, and C) supports the photosensitive member 4 that is a latent image carrier and various devices disposed around the photosensitive member 4 as a unit by a common support. It can be attached to and detached from the copying machine 100 main body. Taking the black image forming unit 3K as an example, this has a developing device 6K for developing the electrostatic latent image formed on the surface of the photosensitive member 4K into a black toner image in addition to the photosensitive member 4K. Further, it also includes a drum cleaning device 15K that cleans transfer residual toner adhering to the surface of the photoreceptor 4K after passing through a primary transfer nip for K described later. In the copying machine 100, a so-called tandem type in which four image forming units 3 (K, Y, M, and C) are arranged so as to face an intermediate transfer belt 91, which will be described later, along the endless movement direction. It is configured.

  FIG. 3 is an enlarged view of one of the four image forming units 3 (K, Y, M, C). The four image forming units 3 (K, Y, M, and C) have substantially the same configuration except that the colors of the toners to be used are different from each other. Therefore, in FIG. , M, and C are omitted. As shown in FIG. 3, the image forming unit 3 includes a charging roller 5 as a charging device, a developing device 6, a drum cleaning device 15, a static eliminating lamp 22 as a static eliminating device, and the like around the photosensitive member 4.

  In the copying machine 100, a drum-shaped member in which a photosensitive layer is formed by coating a photosensitive organic photosensitive material on a base tube made of aluminum or the like is used as the photosensitive member 4. However, an endless belt may be used as the photoreceptor.

  The developing device 6 carries a two-component developer containing a magnetic carrier (not shown) and a non-magnetic toner on a developing roller 12 that is a developer carrying member, and a developing region that is a facing portion between the developing roller 12 and the photosensitive member 4. Then, toner is supplied to the electrostatic latent image on the photosensitive member 4 to visualize the electrostatic imagination. Further, the developing device 6 includes a developer accommodating portion that accommodates a two-component developer supplied to the surface of the developing roller 12, and the developer accommodating portion is provided with a stirring member (not illustrated) that agitates the accommodated two-component developer. It has been. The developing roller 12 includes a non-magnetic cylindrical developing sleeve that is rotatably arranged, and a magnet roller that is non-rotatably provided therein. The magnet roller has a plurality of magnetic poles that are sequentially arranged in the rotation direction of the developing sleeve. Each of these magnetic poles applies a magnetic force to the two-component developer on the developing sleeve at a predetermined position in the rotational direction. As a result, the two-component developer in the developer accommodating portion is attracted and carried on the surface of the developing sleeve, and a magnetic brush is formed along the magnetic force lines on the surface of the developing sleeve. The magnetic brush is transported to the developing area after being regulated to an appropriate layer thickness when passing through a position facing a developer regulating member (not shown) as the developing sleeve rotates. Then, development is performed by transferring toner onto the electrostatic latent image by a potential difference between the developing bias applied to the developing sleeve and the electrostatic latent image on the photoreceptor 4. Further, the two-component developer constituting the magnetic brush that has passed through the developing area and then returned to the developing device 6 again with the rotation of the developing sleeve is developed under the influence of the repulsive magnetic field formed between the magnetic poles of the magnet roller. After detachment from the sleeve surface, it is returned to the developer container. A toner concentration sensor (not shown) is disposed in the developer accommodating portion, and the toner concentration of the two-component developer in the developer accommodating container is within a predetermined range based on the detection result by the toner concentration sensor. As described above, a toner replenishing device (not shown) is controlled to replenish an appropriate amount of toner to the two-component developer.

  In the printer unit 1, as shown in FIG. 2, the image forming process described so far is applied to the photosensitive members 4 (K, Y, M, C) of the four image forming units 3 (K, Y, M, C). As a result, K, Y, M, and C toner images are formed.

  As shown in FIG. 2, a transfer unit 90 is disposed below the four image forming units 3 (K, Y, M, C). The transfer unit 90 includes an intermediate transfer belt 91 as a toner image carrier stretched by a plurality of stretching rollers (92, 93, 94), and the first stretching roller 92 sandwiches the intermediate transfer belt 91. A belt cleaning device 32 is disposed at the facing position. The belt cleaning device 32 is arranged to remove toner remaining on the intermediate transfer belt 91 after passing through a secondary transfer nip described later. In the transfer unit 90, the intermediate transfer belt 91 is moved endlessly in the clockwise direction in the figure (the direction of arrow A in FIG. 2) while being in contact with the photoreceptor 4 (K, Y, M, C). As a result, primary transfer nips for K, Y, M, and C where the photoreceptors 4 (K, Y, M, and C) and the intermediate transfer belt 91 abut are formed. In the vicinity of the primary transfer nips for K, Y, M, and C, the intermediate transfer belt 91 is moved to the photosensitive member 4 by the primary transfer roller 95 (K, Y, M, and C) disposed in the belt loop. It is pressed toward (K, Y, M, C). A primary transfer bias is applied to the four primary transfer rollers 95 (K, Y, M, and C) by a power source (not shown). Thus, in the primary transfer nip for K, Y, M, and C, the primary transfer that electrostatically moves the toner image on the photoreceptor 4 (K, Y, M, and C) toward the intermediate transfer belt 91 that is a transfer body. An electric field is formed. In the drawing, toner images are sequentially superimposed on the surface of the intermediate transfer belt 91 that sequentially passes through the primary transfer nips for K, Y, M, and C along with the endless movement in the clockwise direction. Primary transcription. By this primary transfer of superposition, a four-color superposed toner image (hereinafter referred to as a four-color toner image) is formed on the surface of the intermediate transfer belt 91. The primary transfer device according to the present embodiment employs a configuration including a primary transfer roller 95 as a primary transfer member, but a conductive brush, a non-contact corona charger, or the like can also be employed as the primary transfer member.

  In FIG. 3, untransferred toner that has not been primarily transferred to the intermediate transfer belt 91 adheres to the surface of the photoreceptor 4 after passing through the primary transfer nip. This transfer residual toner is removed from the surface of the photoreceptor 4 by the drum cleaning device 15 of the image forming unit 3.

  As the drum cleaning device 15, a device that scrapes off and removes transfer residual toner from the surface of the photoconductor 4 after passing through the primary transfer nip by a polyurethane rubber cleaning blade 16 in contact with the photoconductor 4 is used. Yes. The cleaning blade 16 is bonded (hot melt) to a metal support member fixed to the casing of the image forming unit 3, and comes into contact with the photoconductor 4 in the counter direction. The counter direction is the direction of the blade such that the front end side of the cleaning blade 16 cantilevered by the support member is positioned upstream of the rear end side (free end side) in the rotation direction of the photosensitive member 4. . Here, the toner recovered by the drum cleaning device 15 is recovered by the developing device 6 and reused by a recovery screw and a toner recycling device (not shown).

  The static eliminator included in the image forming unit 3 of the present embodiment has a configuration including a static eliminator lamp 22, and irradiates light to initialize the surface potential of the photoreceptor 4. The surface of the photoreceptor 4 that has been neutralized by the static elimination lamp 22 is uniformly charged by a charging roller 5 that generates a discharge with the photoreceptor 4 by applying a charging bias, and then the light from the optical writing device 2 is used. Write processing is performed. The charging device provided in the image forming unit 3 is a contact charging type charging device employing a charging roller 5. This charging device uniformly charges the surface of the photosensitive member 4 by bringing the charging roller 5 into contact with the surface of the photosensitive member 4 and applying a voltage to the charging roller 5. In addition, as a charging device for uniformly charging the photosensitive member 4, a charging device of a non-contact charging type using a scorotron charger or the like can be used instead of the charging roller type.

  As shown in FIG. 2, in the printer unit 1, an endless paper conveyance belt 29 that is a secondary transfer belt is hung between a driving roller 30 and a secondary transfer roller 31 below the transfer unit 90 in the drawing. A paper transport unit 28 is provided as a secondary transfer unit that passes and moves endlessly. In the copying machine 100, the intermediate transfer belt 91 and the paper transport belt 29 are sandwiched between the secondary transfer roller 31 of the paper transport unit 28 and the lower stretching roller 94 of the transfer unit 90. As a result, a secondary transfer nip is formed in which the surface of the intermediate transfer belt 91 and the surface of the paper transport belt 29 abut. A secondary transfer bias is applied to the secondary transfer roller 31 by a power source (not shown). On the other hand, the lower stretching roller 94 of the transfer unit 90 is grounded. Thereby, a secondary transfer electric field is formed in the secondary transfer nip. The member that forms the secondary transfer nip in contact with the intermediate transfer belt 91 is not limited to a belt-like member such as the paper transport belt 29, and a roller-like transfer roller may be used.

  A registration roller pair 33 is disposed on the right side of the secondary transfer nip in the figure. The registration roller pair 33 sends the transfer paper P sandwiched between the rollers to the secondary transfer nip at a timing at which the transfer paper P can be synchronized with the four-color toner image on the intermediate transfer belt 91. In the secondary transfer nip, the four-color toner images on the intermediate transfer belt 91 are collectively secondary transferred onto the transfer paper P due to the influence of the secondary transfer electric field and the nip pressure, and become a full color image combined with the white color of the transfer paper P. The transfer paper P that has passed through the secondary transfer nip and has a toner image transferred to the surface thereof is separated from the intermediate transfer belt 91 and held on the surface of the paper transport belt 29, while the endless movement of the transfer paper P is performed. It is conveyed to.

  The transfer residual toner that has not been transferred to the transfer paper P at the secondary transfer nip adheres to the surface of the intermediate transfer belt 91 that has passed through the secondary transfer nip. This transfer residual toner is scraped off and removed by the belt cleaning device 32 arranged so that the cleaning member contacts the intermediate transfer belt 91.

  As will be described in detail later, the transfer paper P transported to the fixing device 60 is fed out of the fixing device 60 by applying a fixing solution in the fixing device 60, and then sent out from the fixing device 60 to be transferred onto the paper discharge tray 10. The paper is discharged.

  As shown in FIG. 1, in the copying machine 100, a switchback device 36 that is a transfer paper reversing device is disposed below the paper transport unit 28 and the fixing device 60. When image formation is performed on both sides, the path of the transfer paper P that has undergone image fixing processing on one side is switched to the switchback device 36 side by controlling the switching claw, and the transfer paper P is reversed there, and then again. Transport toward the next transfer nip. Then, the transfer sheet P on which the image is subjected to the secondary transfer process and the fixing process on the other side is discharged onto the discharge tray 10.

  Next, the fixing device 60 that is a feature of the present invention will be described. FIG. 4 is an explanatory diagram schematically showing the fixing device 60 of the present embodiment. The resin fine particles in the present invention are toner particles. The fixing device 60 includes a foam-like fixer generating unit 130 as a foam-like fixer generating unit for generating a foam-like fixer F in which a liquid fixer 132 containing a softening agent is foamed, and the generated foam-like fixer F. And a fixer application unit 600 which is a fixer application unit for applying the toner to the transfer paper P as a recording medium.

  The foam-like fixer generation unit 130 includes a fixer bottle 131 serving as a fixer containing unit for storing the liquid fixer 132, and a foam-like foam containing a large amount of bubbles by dispersing bubbles in the liquid fixer 132. A fixing liquid foaming device 500 serving as a fixing liquid foaming means serving as a fixing liquid F; The liquid fixer 132 in the fixer bottle 131 is transported to the fixer foaming device 500 via the fixer transport pipe by driving a fixer transport pump (not shown). Are mixed, dispersed, and foamed to form a foamy fixing solution F. As the fixer foaming device 500, for example, a foam-like fixer generating unit described in Patent Document 3 can be used. If the liquid fixer 132 can be a foamy fixer F having a desired bubble diameter, this can be used. It is not limited to.

  The fixing solution application unit 600 applies the foamy fixing solution F having a desired bubble diameter generated by the foamed fixing solution generation unit 130 to the unfixed toner image T on the transfer paper P. The fixing liquid application unit 600 is supplied with the foamy fixing liquid F from the fixing liquid foaming device 500 and applies the foaming fixing liquid F to the transfer paper P at the application position C, and an application roller 61 61, and a pressure roller 62 disposed so as to face the coating position C. The application roller 61 and the pressure roller 62 rotate so that their surfaces move in synchronization with the movement of the transfer paper P.

  The foam-like fixer F supplied in a thin film form from the foam-like fixer generator 130 onto the surface of the application roller 61 reaches the application position C by the surface movement of the application roller 61, that is, rotation. The transfer paper P carrying the unfixed toner image T conveyed to the fixing device 60 by a conveyance member (not shown) is sandwiched between the nip portion between the application roller 61 and the pressure roller 62 at the application position C, and is fixed in a foam state. The liquid F is applied to the unfixed toner image T. After passing through the nip portion, the toner particles that have been softened or swollen by being applied with a fixing solution are hardened again and are fixed on the transfer paper P, thereby forming a fixed toner image Ta.

  The fixing liquid application unit 600 is downstream of the application position C in the surface movement direction of the application roller 61 and upstream of the position where the foamy fixing liquid F is supplied from the foamy fixing liquid generator 130. And a fixer recovery device 200. The fixing liquid recovery apparatus 200 receives the foamy fixing liquid F that has not been transferred from the coating roller 61 to the transfer paper P at the application position C and the residual foamy fixing liquid Fb that is made up of a small amount of offset toner Tb that has been transferred from the transfer paper P. It is designed to be removed and collected.

In the fixing device 60 shown in FIG. 4, the foamy fixing solution F supplied from the foamy fixing solution generator 130 to the application roller 61 is supplied in a thin film state. As a configuration for forming a thin layer of the foam fixing solution F on the coating roller 61, the coating roller 61 is provided between the position where the foam fixing solution F is supplied from the foam fixing solution generator 130 and the coating position C. You may provide the film thickness control means which makes the above foamy fixing solution F a desired film thickness. As the foamed fixing solution F to be applied using the coating member, an experiment was performed in which the density of the foamed fixing solution F was changed and fixed, and the ratio of the fixing solution and the air constituting the foamed fixing solution F was determined. Is about 1:25 to 1:50, that is, the density is preferably in the range of 0.04 to 0.02 [cm ³ ]. If the density of the foam-like fixing solution F is higher than this range, it becomes a liquid state and on the surface of the coating roller that has passed through the coating position in the same manner as a conventional fixing device that applied a normal liquid fixing solution. A so-called offset in which the toner is caught in the fixing liquid and the application roller shifts to a warp easily occurs, and image deterioration occurs. On the contrary, when the density of the foam fixing solution F is lower than this range, the foam fixing solution F is in a state called dry foam. When in a dry foam state, it is difficult for bubbles to break, and the required amount of fixer does not migrate to the recording medium, resulting in poor fixing, or lower use efficiency of the fixer, which consumes more fixer than necessary. Troubles such as.

  Further, as a result of experiments, it was found that the bubble diameter of the foam-like fixing solution F is desirably about 20 [μm] on average. The foam-like fixer F is composed of a fixer part and an air part, but since there is no fixer in the air part, if the bubble diameter is large, the toner in the air part is not softened and fixed. In other words, uneven fixing occurs. On the other hand, when the bubble diameter is too small, the wettability to the application roller 61 becomes extremely low, and the film becomes a uniform thin film on the application roller 61, resulting in uneven fixing. For these reasons, the density and bubble diameter of the foam-like fixing solution F have a good range for the fixing performance. Of course, good portions differ depending on the type of fixing solution, the type of toner, and the like, but such a range basically exists in a method in which a fixing solution is foamed and applied to toner.

  The required film thickness of the foamy fixing solution F on the application roller 61 can be easily obtained by the following calculation. First, it is assumed that the amount of fixing liquid necessary for one transfer sheet P of A4 size (297 [mm] × 210 [mm]) is 0.1 [g]. As a result of experiments, the amount of fixing solution required per A4 size sheet on actual plain paper was 0.1 [g]. However, the amount of fixing solution required if the type of transfer paper P changes. Can change. When the amount of the fixing solution is larger than the necessary amount of the fixing solution, the transfer paper P swells and the curling becomes conspicuous, and the commercial value is remarkably reduced. Further, if the amount of the fixing solution is less than the necessary amount of fixing solution, fixing failure occurs.

Assuming that the density of the above-described foam-like fixing solution F is 0.02 [g / cm ³ ], the specific gravity of the fixing solution is 1, and the necessary bubble film thickness on the coating roller 61 is t [mm], (297 [mm] ] × 210 [mm] × t [mm]) × 0.02 / 1000 [g / mm ³ ] = 0.1 [g], so that t = 0.08 [mm]. The film thickness required for the fixing solution F is about 80 [μm]. Actually, not all of the foamy fixing solution F is transferred to the transfer paper P. For this reason, if the transfer rate of the foam-like fixing liquid F from the application roller 61 to the transfer paper P is 90 [%], 80 [μm] /0.9=88 [μm].

  As described above, a thin foam fixing solution F having a film thickness of about 90 [μm] is formed on the surface of the application roller 61, and this is applied to the transfer paper P at the application position C. Thus, not all of the foamy fixing solution F on the application roller 61 is applied to the transfer paper P. As described above, the transfer rate (the amount of the foam-like fixing solution F per unit area on the coating roller 61 just before reaching the coating position C is defined as the amount of the foam-like fixing solution F on the transfer paper P just after passing through the coating position C. The value divided by the amount is about 90% at best.

  That is, about 10 [%] of the foamy fixing solution F supplied on the surface of the application roller 61 remains on the application roller 61 after passing through the application position C. Since the residual fixing liquid Fb remaining on the application roller 61 contains toner that has been slightly removed (offset) from the transfer paper P at the application position C, the residual fixing liquid Fb is reliably removed from the application roller 61. There is a need. If the residual foam fixing solution Fb is not removed well, when the new foam fixing solution F is supplied again from the foam fixing solution generator 130, it remains in the new foam fixing solution F controlled to a desired state. When the foam-like fixing solution Fb is mixed, the uniformity and the supply amount of the foam-like fixing solution F are changed from a desired state. Further, when the offset toner Tb is re-transferred to the next transfer paper P, an image defect may occur, and the fixing quality may be seriously damaged. Therefore, in the present embodiment, the fixing device 60 includes the application roller cleaning device 20 that removes the residual fixing liquid Fb from the application roller 61.

  Next, the characteristic part of the fixing device 60 of the present embodiment will be described.

  As shown in FIG. 4, the fixing device 60 includes a fixing solution collecting device 200 that removes and collects the residual foamy fixing solution Fb from the application roller 61. The residual foam-like fixing solution Fb is the foam-like fixing solution F that has not contributed to the fixing, that is, the foam-like fixing solution F that has not been transferred to the transfer paper P and remains on the surface of the coating roller 61. A small amount of offset toner Tb transferred from.

  The fixing liquid recovery apparatus 200 includes an application roller cleaning device 20 as an application member cleaning unit that cleans the application roller 61. The coating roller cleaning device 20 removes the residual foamy fixing solution Fb remaining on the surface of the coating roller 61 after the coating roller 61 has passed the coating position C where the foaming fixing solution F is applied to the transfer paper P. A removal blade 201 is provided. The fixing solution removing blade 201 is made of an elastic body such as rubber and is configured to remove the residual foamy fixing solution Fb remaining on the surface of the application roller 61 by elastically contacting the application roller 61. .

  Further, the fixer recovery apparatus 200 includes a residual foam-like fixer containing part 216 that contains the residual foam-like fixer Fb removed from the surface of the coating roller 61 by the fixer removing blade 201, and a residual foam-like fixer containing part. And a suction pump 215 for liquefying the residual foam-like fixing solution Fb by reducing the pressure inside 216.

  The residual foam-like fixer storage part 216 forms an opening 216a for receiving the residual foam-like fixer Fb from the application roller 61 of the fixer application part 600 when opened, and seals the residual foam-like fixer containing part 216 when closed. A shutter 217 is provided. The shutter 217 is opened when the residual foam-like fixing liquid container 216 receives the residual foam-like fixing liquid Fb removed from the surface of the application roller 61 by the fixing liquid removing blade 201, and drives the suction pump 215 to leave the residual foam-like fixing liquid Fb. When the inside of the fixing liquid storage unit 216 is depressurized, it is closed. The residual foam-like fixing solution storage unit 216 is disposed directly below the fixing solution removing blade 201, and the residual foam-like fixing solution Fb that has been removed from the surface of the application roller 61 by the fixing solution removing blade 201 and dropped is opened to the opening 216a. Can accept. Since the residual foam-like fixing solution Fb is filled inside by its own weight, the residual foam-like fixing solution storage portion 216 is inclined so that the back portion (left direction in FIG. 4) is lowered. Has been.

  The fixer recovery apparatus 200 also includes a fixer recovery bottle 220 that recovers the residual foam fixer Fb liquefied in the residual foam fixer storage unit 216, a residual foam fixer storage unit 216, and a fixer recovery. Fixing liquid recovery pipe 226 connected to the bottle 220 and the residual foam fixing liquid Fb liquefied from the residual foam fixing liquid container 216 provided in the middle of the fixing liquid recovery pipe 226 are transferred to the fixing liquid recovery bottle 220. And a fixing liquid recovery pump 225 for performing the fixing. The liquefied residual foamy fixer Fb recovered in the fixer recovery bottle 220 may be returned to the fixer bottle 131 by a pipe and a pump (not shown).

  As described above, in this embodiment, the residual foam-like fixing solution Fb is liquefied and recovered, so that the residual foam-like fixing solution Fb can be liquefied well without using a large-capacity fixing solution recovery bottle 220. Can be recovered. That is, if the residual foam-like fixing solution Fb is stored in the form of foam without being liquefied, the residual foam-like fixing solution Fb has a larger volume than a normal liquid-type fixing solution. There is a problem that the fixing solution recovery bottle 220 is required, resulting in an increase in the size of the apparatus, and it is assumed that the residual foam fixing solution Fb in the residual foam fixing solution storage unit 216 is naturally defoamed over time. When the volume is gradually reduced, it takes a long time for defoaming. Therefore, the residual foam-like fixer container 216 is filled up immediately, and the residue newly removed by the fixer removing blade 201 is removed. There is a problem that it becomes impossible to collect the foamy fixing solution Fb, but the fixing device 60 according to the present embodiment liquefies and collects the residual foaming fixing solution Fb, so that such a problem is avoided. To do That.

  Next, the operation of the fixing liquid recovery device 200 of the fixing device 60 configured as shown in FIG. 4 will be described with reference to FIGS.

  First, as shown in FIG. 5, in the state where the shutter 217 of the residual foam fixing liquid container 216 is opened, the residual foam fixing liquid Fb removed from the surface of the application roller 61 by the fixing liquid removing blade 201 is retained. It is housed in the fixing solution container 216.

  Next, as shown in FIG. 6, the shutter 217 of the residual foam-like fixer container 216 is closed. While the shutter 217 is closed, the residual foam fixing liquid Fb cannot be stored in the residual foam fixing liquid storage unit 216, so it is desirable to stop the supply of the fixing liquid foaming device 500.

  Next, as shown in FIG. 7, the suction pump 215 is operated, and the inside of the residual foam-like fixing liquid storage unit 216 is brought into a reduced pressure state. In addition, since the strength of the foam varies depending on the prescription of the foam-like fixing solution F, it is desirable to set the degree of pressure reduction according to the prescription of the foam-like fixing solution F.

  Next, as shown in FIG. 8, after the residual foam-like fixing solution Fb breaks and liquefies, the suction pump 215 is stopped and the fixing-solution recovery pump 225 is operated, so that the residual foam-like fixing solution storage unit 216 The liquefied residual foamy fixing solution Fb is recovered in the fixing solution recovery bottle 220.

  Here, the defoaming mechanism of the residual foam-like fixing solution Fb when the inside of the residual foam-like fixing solution storage unit 216 is decompressed will be described below. By reducing the pressure of the residual foam fixing solution Fb stored in the residual foam fixing solution storage unit 216, the volume of air confined in the liquid film of the residual foam fixing solution Fb is increased. That is, the volume of bubbles increases due to the reduced pressure. For this reason, by reducing the pressure, the thickness of the liquid film becomes extremely thin, and bubbles can be easily broken and liquefied, and the residual foamy fixing solution Fb can be recovered well.

  As in the fixing liquid recovery device 230 shown in FIG. 9, a plurality of vacuum defoaming mechanisms each including a residual foam fixing liquid storage unit 216, a suction pump 215, a fixing liquid recovery pump 225, and a fixing liquid recovery bottle 220 (see FIG. 9). In FIG. 9, two residual foam-fixing solution storage units 216 close the shutter 217 and liquefy the residual foam-fixing solution Fb, while containing other residual foam-fixing solution Fb. It is preferable to always operate a set of vacuum defoaming mechanisms by opening the shutter 217 in the unit 216 to accommodate the residual foam-like fixing solution Fb. In this case, even if the copier 100 is continuously operated and the residual foam-like fixing solution Fb always enters the residual foam-like fixing solution container 216, the residual foam-like fixing solution Fb is continuously contained, liquefied and recovered. be able to. In FIG. 9, the residual foam fixing solution Fb removed from the surface of the application roller 61 by the fixing liquid removing blade 201 is fixed between the application roller 61 and the residual foam fixing liquid container 216. A guide member 231 for guiding the liquid container 216 is disposed.

  Hereinafter, with the configuration of the fixing device 60 of the present embodiment, the residual foamy fixing solution Fb is liquefied and recovered (Example 1), and recovered without reducing pressure (Comparative Example 1 and Comparative Example 2). The results of comparing and comparing the evaluation tests will be described.

[Example 1]
<Prescription of Fixing Solution> A fixing solution was prepared by mixing and stirring at the following component ratio.
・ Diluting solvent: 59% by weight of ion-exchanged water
・ Softener: Diethoxyethyl succinate (Croda Croda DES) 5wt%
・ Penetration agent: Polyether-modified silicone (Toray Dow Corning Silicone SS2802) 1wt%
・ Thickener: Propylene glycol 30wt%
・ Foaming agent: palm fatty acid diethanolamide 2wt%
・ Foaming agent: Sodium alkyl sulfate 2wt%
・ PH adjuster: Triethanolamine 1wt%
<Coating device>
As shown in FIG. 4, the fixer supplied from the fixer bottle 131 was introduced into the fixer foaming device 500 (a bubbling stirring method) to prepare a foamy fixer F. Further, by setting the gap between the fixing liquid foaming device 500 and the coating roller 61 to 70 μm, the foam film on the coating roller became 90 μm. At that time, the bulk density of the foam-like fixing solution F was 0.02 g / cm ³ .

The configuration and application conditions of the application roller 61 were as follows.
Application roller 61: SUS roller (φ30) coated with PFA resin by baking
-Paper transport speed: 150 mm / s
-Load between pressure roller and application roller: 196N on one side
<Residual foamy fixer recovery mechanism>
The residual foam-like fixing solution recovery mechanism includes a residual foam-like fixing solution storage unit 216, a suction pump 215, a fixing solution recovery pump 225, and a fixing solution recovery bottle 220 shown in FIG. During the collecting state, the shutter 217 is closed, and the inside of the residual foam-like fixing liquid storage unit 216 is depressurized. The suction pump 215 used for this decompression had a capacity of 50 mL / min. The liquefied residual foamy fixing solution Fb was recovered in the fixing solution recovery bottle 220 by operating the fixing solution recovery pump 225 of FIG.

  IpsioColorCX8800 (manufactured by Ricoh) as the printer, PPC paper as the transfer paper P, 100 sheets of unfixed toner color images formed on the transfer paper P are passed continuously, and the residual foam-like fixer recovery mechanism described above Was operated for about 15 seconds, and the next 100 sheets of transfer paper P were immediately passed. Then, a total of 500 transfer sheets P were passed.

Regarding the evaluation here, the fixed image quality and the state of the residual foam-like fixing liquid storage unit 216 were determined based on the following criteria.
・ Fixed image quality => Evaluation: ○ ... There is no toner offset, the fixed image is always in the same state, and the quality is good.
・ Fixed image quality ⇒ Evaluation: × ・ ・ ・ There is an offset, the image is distorted, a stable fixed image is not output, and the quality is poor.
-State of residual foam-like fixer accommodating section ⇒ Evaluation: ○ ... The foam-like fixer does not overflow from the residual foam-like fixer accommodating part 216, and there is no problem in recovery.
-State of residual foamy fixer container ⇒ Evaluation: × ... The state of foamy fixer overflowing from the residual foamy fixer container 216 or a problem in recovery.

[Comparative Example 1] A recovery method in which the residual foam fixing solution Fb stored in the residual foam fixing solution storage section 216 is overheated and liquefied.
Only the residual foam-like fixer accommodating portion 216 was configured as follows, and the suction pump 215 was not operated, and the rest was carried out in the same manner as in Example 1.
<Foam Fixing Liquid Recovery Unit> A heater was mounted on the bottom surface of the residual foam fixing solution storage unit 216 in FIG. 4, and the shutter 217 was closed and set to 80 ° C. in the recovery state.

[Comparative Example 2] A recovery method for collecting the residual foam-like fixer Fb accommodated in the residual foam-like fixer containing part 216 in the form of bubbles.
While the shutter 217 of the residual foam-like fixing liquid storage unit 216 in FIG. 4 was left open, the suction pump 215 was not operated, and the fixing liquid recovery pump 225 was operated.

以下に、評価試験の結果の詳細を示す。
・実施例１・・・定着画像品質が安定しており、残留泡状定着液収容部２１６も溢れることなく、綺麗に残留泡状定着液Ｆｂを回収できていた。
・比較例１・・・残留泡状定着液収容部２１６を加熱することで、残留泡状定着液Ｆｂを綺麗に回収できるものの、熱を使ったため、塗布ローラ６１が温まってしまい、上流の泡が不安定になり、定着画像にオフセットやムラが生じてしまった。
・比較例２・・・残留泡状定着液収容部２１６のシャッター２１７を開放状態にし、定着液回収ポンプ２２５を稼動させ、泡の状態での回収を試みたが、泡がなかなか残留泡状定着液収容部２１６の定着液回収ポンプ２２５へ接続する吸引口に来なかったり、泡が吸引入口に充填されていないと泡が吸引されないため、満杯になった残留泡状定着液収容部２１６から残留泡状定着液Ｆｂが溢れて落下してしまい、真下に位置する定着画像を汚してしまった。 Table 1 shows the results of evaluation tests of Example 1, Comparative Example 1, and Comparative Example 2.

Details of the evaluation test results are shown below.
Example 1 The fixed image quality was stable, and the residual foam-like fixer Fb could be collected neatly without overflowing the residual foam-type fixer container 216.
Comparative Example 1... Although the residual foam-like fixer Fb can be collected cleanly by heating the residual foam-like fixer container 216, the application roller 61 is warmed due to the use of heat, and the upstream foam Became unstable and offset or unevenness occurred in the fixed image.
Comparative Example 2 ... The shutter 217 of the residual foam-like fixer storage unit 216 was opened, the fixer recovery pump 225 was operated, and recovery was attempted in the form of foam. Since the bubbles are not sucked unless they come to the suction port connected to the fixing solution recovery pump 225 of the liquid storage unit 216, or the bubbles are not filled in the suction inlet, the residual from the filled residual foam fixing solution storage unit 216 remains. The foamy fixing solution Fb overflowed and dropped, and the fixed image located immediately below was soiled.

  From the above results, it is clear that the liquefied residual foam fixing solution Fb can be recovered satisfactorily by depressurizing and liquefying the residual foam fixing solution Fb stored in the residual foam fixing solution storage section 216. It was. That is, when the residual foam-like fixing solution Fb is depressurized, the air trapped in the liquid film is increased and the volume of the bubbles is increased. Therefore, the thickness of the liquid film becomes extremely thin and bubbles are easily broken and liquefied. Therefore, the residual foamy fixing solution Fb can be recovered satisfactorily. Note that the present invention is not limited to the configurations disclosed in the above-described embodiments, and it goes without saying that various modifications and substitutions are possible within the scope described in the claims.

  As described above, the fixing device 60 according to the present embodiment includes the fixing solution recovery device 200 that recovers the residual foamy fixing solution Fb remaining on the application roller 61 without being applied to the transfer paper P, and recovering the fixing solution. An apparatus 200 for storing a residual foam-like fixing solution Fb containing a residual foam-like fixing solution Fb; and a suction pump 215 for depressurizing the residual foam-like fixing solution containing unit 216 to liquefy and collect the residual foam-like fixing solution Fb; A fixing liquid recovery pump 225 and a fixing liquid recovery bottle 220, and the suction pump 215 is driven to depressurize the inside of the residual foam fixing liquid storage unit 216, thereby liquefying the residual foam fixing liquid Fb. The liquefied residual foamy fixing solution Fb is transferred to a fixing solution recovery bottle 220 by a fixing solution recovery pump 225 and recovered.

  With this configuration, by reducing the pressure of the residual foam-fixing solution Fb in the residual foam-fixing solution container 216, the residual foam-fixing solution Fb has an extremely thick liquid film as the foam volume increases. Since it becomes thin, it easily breaks and liquefies, reducing its volume. This facilitates the transfer of the liquefied residual foamy fixing solution Fb to the fixing solution recovery bottle 220, and does not require the use of a large capacity fixing solution recovery bottle 220. Therefore, in the configuration in which the resin fine particles are softened by using the foam fixing solution F and fixed on the transfer paper P, the residual foam fixing solution Fb, which is the foam fixing solution F that has not contributed to fixing, can be recovered well. Can do.

  Further, in the fixing device 60 according to the present embodiment, the residual foam-like fixer container 216 forms an opening 216a that receives the residual foam-like fixer Fb from the application roller 61 of the fixer application part 600 when opened. The shutter 217 seals the residual foam-like fixing solution storage portion 216 when closed.

  With this configuration, by opening the shutter 217, it is possible to form the opening 216 a for receiving the residual foam-like fixing liquid Fb in the residual foam-like fixing liquid storage part 216 and to close the shutter 217 so as to fix the residual foam-like fixing. Since the liquid container 216 can be sealed in preparation for decompression, the member for forming the opening 216a in the residual foam fixing liquid container 216 and the residual foam fixing liquid container 216 are sealed for decompression. Therefore, it is not necessary to provide a separate member, and the size of the apparatus can be reduced, the cost can be reduced, and the failure rate can be reduced by suppressing the number of parts.

  Further, in the fixing device 60 according to the present embodiment, the fixing liquid application unit 600 rotates in synchronization with the movement of the transfer paper P, and the foamy fixing liquid F supplied to the surface faces the transfer paper P. An application roller cleaning that has an application roller 61 that applies to the transfer paper P at the application position C, and in which the fixing liquid recovery device 200 removes the residual foamy fixing liquid Fb from the surface of the application roller 61 after passing through the application position C. The apparatus has an apparatus 20 and is characterized in that the residual foamy fixing liquid Fb removed by the application roller cleaning apparatus 20 is collected.

  With this configuration, the fixer recovery device 200 removes the residual foamy fixer Fb from the surface of the applicator roller 61 after passing the applicator position C by the applicator roller cleaning device 20, so that the applicator roller of the fixer applicator 600 The residual foam-like fixer Fb can be recovered satisfactorily without adversely affecting the application of the foam-like fixer F to the transfer paper P by 61.

  Further, in the fixing device 60 according to the present embodiment, the application roller cleaning device 20 is made of an elastic body and contacts the surface of the application roller 61 to remove the residual foamy fixing liquid Fb from the surface of the application roller 61. It has a liquid removing blade 201.

  With this configuration, the fixing liquid removing blade 201 made of an elastic body elastically contacts the surface of the application roller 61, so that the residual foamy fixing liquid Fb is removed from the surface of the application roller 61 without damaging the application roller 61. In addition, since the positioning accuracy required for the relative position between the fixing solution removing blade 201 and the application roller 61 can be relaxed, the assembly process of the apparatus can be facilitated.

  Further, the copying machine 100 according to the present embodiment includes a printer unit 1 that forms a toner image on the transfer paper P based on image information using toner containing resin fine particles containing a resin and a colorant, and a printer. And a fixing device 60 as a fixing unit that fixes the toner image on the transfer paper P by applying a foamy fixing solution F to the surface of the transfer paper P on which the toner image is formed by the unit 1. .

  With this configuration, in the copying machine 100 including the fixing device 60, the residual foam-like fixing solution Fb that has not contributed to the fixing can be recovered well by liquefying the residual foam-like fixing solution Fb.

  As described above, in the fixing device and the image forming apparatus according to the present invention, the residual foam fixing solution that did not contribute to fixing in the configuration in which the resin fine particles are softened and fixed to the recording medium using the foam fixing solution. And a fixing device that fixes a resin fine particle on a recording medium by applying a fixing liquid that dissolves or swells the resin fine particle such as toner to the resin fine particle. Useful as a forming device.

1 Printer unit 20 Application roller cleaning device (application member cleaning means)
60 fixing device 61 coating roller (coating member)
62 Pressure roller 100 Copying machine (image forming apparatus)
130 Foam Fixer Generation Unit (Fixing Solution Foaming Means)
131 Fixing solution bottle 132 Liquid fixing solution 200, 230 Fixing solution collecting device (foam-like fixing solution collecting means)
201 Fixing liquid removing blade (cleaning member)
215 Suction pump (liquefaction recovery means)
216 Residual foam-like fixing liquid container 216a Opening 217 Shutter (opening / closing member)
220 Fixing liquid recovery bottle (liquefaction recovery means)
225 Fixer recovery pump (liquefaction recovery means)
226 Fixing liquid recovery tube 231 Guide member 500 Fixing liquid foaming device 600 Fixing liquid application part (foaming fixing liquid applying means)
C Application position F Foam fixer Fb Residual foam fixer P Transfer paper (recording medium)
T Unfixed toner image Ta Fixed toner image Tb Offset toner

JP 2006-78573 A JP 2004-109749 A JP 2007-219105 A Japanese Patent Laid-Open No. 9-94561 JP-A-9-268393 Japanese Patent No.3051495

Claims (5)

A fixing liquid foaming means for dispersing a bubble in a fixing liquid containing a softening agent that softens resin fine particles containing the resin by dissolving or swelling at least a part of the resin to generate a foamy fixing liquid;
A foam-like fixing solution applying means for applying the foam-like fixing solution to a recording medium having a resin particle layer formed of the resin particles formed on the surface thereof,
In the fixing device that softens the resin fine particles by applying the foam-like fixing solution to the recording medium by the foam-like fixing solution applying unit, and fixes the fine particles to the recording medium.
A foam-like fixing solution collecting means for collecting a residual foam-like fixing solution remaining in the foam-like fixing solution applying means without being applied to the recording medium;
The foamy fixer recovery means includes
A residual foam-like fixer containing part for containing the residual foam-like fixer;
And a liquefying and collecting means for liquefying and recovering the residual foamy fixer by reducing the pressure of the residual foamy fixer container.   An opening / closing member that forms an opening for receiving the residual foamy fixer from the foamy fixer application means when the residual foamy fixer container is opened, and that seals the recovered foamy fixer container when closed The fixing device according to claim 1, further comprising: The foaming fixing solution applying means rotates in synchronization with the movement of the recording medium, and applies the foaming fixing solution supplied to the surface to the recording medium at an application position facing the recording medium. Have
The foam-like fixing liquid recovery means has an application member cleaning means for removing the residual foam-like fixing liquid from the surface of the application member after passing through the application position, and the residual bubbles removed by the application member cleaning means. The fixing device according to claim 1, wherein the fixing solution is recovered.   The said application member cleaning means is comprised from an elastic body, and has a cleaning member which contacts the surface of the said application member, and removes the said residual foam-like fixing liquid from the surface of the said application member. Fixing device. A toner image forming means for forming a toner image on a recording medium based on image information using a toner containing resin fine particles containing a resin and a colorant;
An image forming apparatus comprising: a fixing unit that applies a foamy fixing solution to a surface of a recording medium on which a toner image is formed by the toner image forming unit, and fixes the toner image on the recording medium;
An image forming apparatus comprising the fixing device according to claim 1 as the fixing unit.

Images