JP2010083132A - Image forming apparatus and bubble coater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such a problem that, when surplus bubbles remain on an coating member, the surplus bubbles are fixed and the unevenness of coating occurs in such a case that bubbles are coated. <P>SOLUTION: A treatment liquid is formed into the bubbles 210 and supplied to an coating roller 232 and film thicknesses of the bubbles 210 on the coating roller 232 are made uniform by a stirring roller 233 and a bubble film thickness regulating roller 234. After that, the bubbles 210 are coated to paper 100 conveyed between the coating roller 232 and a pressure roller 235 and after the coating, the surplus bubbles 211 remaining on the coating roller 232 are scraped and removed by a cleaning member 236. Furthermore, the surplus bubbles 212 scraped by the cleaning member 236 are heated by a heating means 237 to liquefy and remove the surplus bubbles 210. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image forming apparatus and a foam coating apparatus.

  As an image forming apparatus such as a printer, a facsimile machine, a copying apparatus, a plotter, and a complex machine of these, for example, an ink jet recording apparatus is known as an image forming apparatus of a liquid discharge recording method using a recording head for discharging ink droplets. . This liquid discharge recording type image forming apparatus means that ink droplets are transported from a recording head (not limited to paper, including OHP, and can be attached to ink droplets and other liquids). Yes, it is also ejected onto a recording medium or a recording medium, recording paper, recording paper, etc.) to form an image (recording, printing, printing, and printing are also used synonymously). And a serial type image forming apparatus that forms an image by ejecting liquid droplets while the recording head moves in the main scanning direction, and a line type head that forms images by ejecting liquid droplets without moving the recording head There are line type image forming apparatuses using

  In the present application, the “image forming apparatus” of the liquid discharge recording method is an apparatus that forms an image by discharging liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, or the like. In addition, “image formation” means not only giving an image having a meaning such as a character or a figure to a medium but also giving an image having no meaning such as a pattern to the medium (simply It also means that a droplet is landed on a medium). The “ink” is not limited to what is called ink, and is not particularly limited as long as it becomes a liquid when ejected. For example, a DNA sample, a resist, a pattern material, etc. Is also included.

  In such a liquid ejection type image forming apparatus, in order to form an image by forming ink containing a coloring material into droplets, feathering in which dots formed by the droplets are disturbed, and ink droplets of different colors When the ink is struck on the paper adjacent to each other, it may cause problems such as color bleeding, which causes the colors to mix with each other and the color boundary to become unclear. There is a problem that it takes.

  Therefore, as described in Patent Document 1, a pretreatment liquid that reacts with ink to prevent bleeding is applied by an application roller as described in the prior art, or the pretreatment liquid is ejected as described in Patent Document 2. A mist is ejected from the head and applied, or, as described in Patent Document 3, a treatment liquid for improving the ink fixing property is applied by a coating roller or the like before or after printing.

JP 2002-137378 A Japanese Patent Laying-Open No. 2005-138502 JP 2003-205673 A

  However, when the pretreatment liquid and the posttreatment liquid are applied to the paper with the application roller or the liquid discharge head as in the above-described prior art, uneven application occurs, and ink is applied to apply a large amount of liquid onto the paper. There is a problem with the quick-drying property of the paper after the reaction, and in particular, the paper tends to curl or bend, so that there is a problem that jamming or the like is likely to occur.

  Therefore, the present applicant has already proposed that the treatment liquid is made into a foam and applied to a member to be coated such as a recording medium. A new problem arises that the foam dries, the treatment liquid component adheres, and problems such as a drop in foam application performance (occurrence of coating unevenness) and a decrease in drive system performance occur.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and enables the foam for modifying the surface of the member to be coated to be stably applied with a uniform thickness and to maintain the quality of the foam to be applied. For the purpose.

In order to solve the above problems, an image forming apparatus according to the present invention provides:
Image forming means for forming an image on a recording medium;
A foam application means for applying at least one of a liquid and a gel to the recording medium or an intermediate member for application to the recording medium,
The foam applying means is
Application means for applying the foam;
The foam application unit includes a cleaning unit that heats and cleans excess foam remaining without being applied by the application unit.

  Here, the cleaning means heats the cleaning member that cleans excess bubbles on the applying means or on the pressurizing means that pressurizes the recording medium or the intermediate member facing the applying means, and the cleaning member. And a heating means.

  In this case, the heating means may be a means for blowing a heated airflow onto the cleaning member.

  Further, the storage tank that stores the processing liquid capable of generating the foam, and the excess liquid that has been returned to the processing liquid from the foam by being heated by the heating unit of the cleaning unit is collected in the storage tank. It can be set as the structure provided with the collection | recovery means.

The foam coating apparatus according to the present invention is:
In a foam application apparatus that applies a foam of at least one of liquid and gel to a member to be coated,
Application means for applying the foam;
And cleaning means for heating and cleaning excess foam remaining without being applied by the applying means.

The “bubble” in the present invention is a liquid or gel that contains a gas such as air and is rounded, and is formed by the surface tension of the liquid that encloses the gas, and maintains a three-dimensional shape for a certain period of time. What you can do. As the foam having such shape-retaining properties, the bulk density is 0.05 g / cm ³ or less, the bubble diameter distribution range is preferably 10 μm to 1 mm, and the average bubble diameter is preferably 100 μm or less. Bubbles are formed in a round shape as a single substance, but when a plurality of bubbles are combined, the shape of each bubble takes a polyhedral shape due to surface tension. “Gel” means a colloidal solution or polymer compound dispersed in a dispersion medium loses its independent mobility due to the interaction, and the particles are connected to each other, forming a net-like or honeycomb-like structure. Means a solidified semi-solid substance.

  According to the image forming apparatus according to the present invention and the foam coating apparatus according to the present invention, the image forming apparatus includes a coating unit that applies foam, and a cleaning unit that heats and cleans excess foam remaining without being applied by the coating unit. Therefore, it becomes possible to apply with a uniform thickness by applying the treatment liquid (liquid or gel) in the form of foam, and it is possible to apply foam of stable quality by cleaning the excess foam.

It is a whole lineblock diagram showing an example of an image forming device provided with a foam application device concerning the present invention. It is a principal part schematic explanatory drawing of the foam application part in 1st Embodiment of this invention. It is a principal part schematic explanatory drawing of the foam application part in 2nd Embodiment of this invention. It is a principal part schematic explanatory drawing of the foam application part in 3rd Embodiment of this invention. It is a principal part schematic explanatory drawing of the foam application part in 4th Embodiment of this invention. It is a whole block diagram which shows the other example of an image forming apparatus provided with the foam coating apparatus which concerns on this invention. It is a principal part schematic explanatory drawing of the foam application part in 5th Embodiment of this invention. It is a perspective explanatory view similarly. It is a principal part schematic explanatory drawing of the foam application part in 6th Embodiment of this invention. It is a principal part schematic explanatory drawing of the foam application part in 7th Embodiment of this invention. FIG. 3 is a block diagram for explaining a control unit of the image forming apparatus. It is a flowchart which shows the 1st example of control of the cleaning operation by a foam application control part. It is a flowchart which shows the 2nd example of control of the cleaning operation by a foam application control part. FIG. 4 is an enlarged explanatory view of a portion where a roller coating surface and unfixed resin fine particles are in contact with each other when the pressure applied on the contact surface between a coating roller and a recording medium is relatively high when applied to an electrophotographic image forming apparatus. . FIG. 6 is an enlarged explanatory view of a portion where the roller application surface and the unfixed resin fine particles are in contact with each other when the pressure on the contact surface between the application roller and the recording medium is relatively low.

Embodiments of the present invention will be described below with reference to the accompanying drawings. First, an example of an image forming apparatus according to the present invention including a foam coating apparatus according to the present invention will be described with reference to FIG. FIG. 1 is an overall configuration diagram of the image forming apparatus.
The image forming apparatus accommodates a recording head unit 101 as an image forming unit that forms an image by ejecting liquid droplets onto a sheet 100 that is a recording medium, a conveyance belt 102 that conveys the sheet 100, and the sheet 100. The present invention applies a bubble to a paper feed tray 103, a paper discharge tray 104 on which a paper 100 on which an image is formed is discharged, and a paper 100 that is a member to be applied on the upstream side of the recording head unit 101 in the paper transport direction. The foam application apparatus (apparatus which applies a foam to a to-be-coated member) 200 is provided.

  The recording head unit 101 is composed of a line type liquid discharge head having a nozzle row in which a plurality of nozzles for discharging droplets are arranged in a length corresponding to the paper width. Yellow (Y), magenta (M), cyan The recording heads 101y, 101m, 101c, and 101k are provided with ink droplets of each color of (C) and black (K). Note that the recording head can be mounted on the carriage as a serial type image forming apparatus.

  The conveyor belt 102 is an endless belt, and is configured to circulate between the conveyor roller 121 and the tension roller 122. The paper 100 can be held on the transport belt 102 by, for example, a configuration that performs electrostatic suction, suction by air suction, or other known transport means.

  The paper 100 stored in the paper feed tray 103 is separated one by one by the pickup roller 131, fed by the transport roller 132, transported by the transport roller pair 133, 134 through the transport path 135, and then by the foam coating device 200. After the foam application, it is fed onto the conveyor belt 102 and held.

  Then, droplets of each color are ejected from the head unit 101 while being transported by the circular movement of the transport belt 102, and an image is formed on the paper 100 on which bubbles are applied. Thereafter, the paper 100 is discharged to the paper discharge tray 104. The

  On the other hand, the foam applicator 200 is a container that is a storage tank containing a liquid or gel or liquid and gel (hereinafter collectively referred to as “treatment liquid” or “setting agent”) 201 that can be made into foam. 202, a pump 203 that pumps the processing liquid 201 from the container 202, a first bubble generation unit 205 that generates bubbles 210 a from the processing liquid 201 supplied via the supply path 204 by the pump 203, and first bubble generation A foam transport path 206 that is a path for sending the foam 210a from the unit 205, a second foam generation section 207 that generates a small foam (small foam) 210 by shearing the foam 210a transported in the foam transport path 206 a plurality of times, And a foam application unit 208 for applying the foam 210 to a recording medium (paper 100).

  Here, the treatment liquid 201 that can be foamed is a modifying material that modifies the surface of the paper 100 by being applied to the surface of the paper 100. For example, the treatment liquid 201 is applied in advance to the paper 100 (not limited to paper as a material as described above) without unevenness, so that moisture of the ink can quickly permeate the paper 100 and increase the color component. Fixing agent (setting agent) that prevents bleeding (feathering, bleeding, etc.) and back-through by increasing viscosity and further drying, and increases productivity (number of images output per unit time). is there.

  In terms of composition, this treatment liquid 201 is, for example, cellulose that promotes moisture permeation with respect to a surfactant (any one of anionic, cationic, nonionic, or a mixture of two or more thereof). And the like (hydroxypropylcellulose etc.) and a solution to which a base such as talc fine powder is added. Furthermore, fine particles can be contained.

  The first bubble generation unit 205 generates bubbles 210 a by supplying high-pressure air 222 from the high-pressure air supply unit 221 to the processing liquid 201 in the bubble generation container 220 via the high-pressure air supply path 223. By generating and filling bubbles 210a in the bubble generation container 220, the bubbles 210a are supplied toward the bubble application unit 208 via the bubble conveyance path 206 by the pressure. In addition, the pump 203 closes the supply path 204 so that the bubbles 210a and the process liquid 201 do not flow backward through the supply path 204 for supplying the processing liquid 201 during the generation of bubbles.

  The second foam generation unit 207 is one or a plurality of foam shearing members 241 (here, three of 241a, 241b, and 241c) formed of a mesh-like or porous member having a plurality of holes in the foam transport path 206. The foam 210a transported in the foam transport path 206 is sequentially sheared into foams 210b and 210c having a reduced diameter, and passes through the final stage foam shearing member 241 so that the size is suitable for application. Bubbles 210 are formed.

  That is, since the desired fine bubbles 210 suitable for coating and image formation cannot be obtained simply by generating by supplying the high-pressure air in the first bubble generating unit 205, the large-diameter bubbles generated by supplying the high-pressure air ( The large bubbles 210a are sheared by the bubble shearing member 241 to be miniaturized into bubbles (small bubbles) 210 having a small diameter suitable for application and image formation.

  By doing so, it is possible to send the foam 210 suitable for application to the foam application unit 208 while efficiently generating the foam 210 while conveying the foam. In this case, since the bubbles are conveyed by the deposition force, the conveyance of the bubbles is also stopped by stopping the bubble generation of the first bubble generation unit 205.

In addition, if the size of the bubble in this case is demonstrated, the "large bubble" and "small bubble" which distinguish the size of a bubble are defined as follows.
Large bubbles: Refers to “first state bubbles”. Although it is generated using a liquid (or a gel or both) that becomes a foam, it refers to a foam that cannot exert the effect of applying a “bubble” described later.
Small bubbles: Refers to “second state bubbles”. This refers to bubbles generated using large bubbles (first state bubbles), and the bubble diameter is smaller than large bubbles (first state bubbles). It refers to the foam that can exert the effect.

As described above, a bubble defined as a small bubble is a liquid or gel that contains a gas such as air and is rounded, and is formed by the surface tension of the liquid that encloses the gas. The shape can be maintained, the bulk density is 0.05 g / cm ³ or less, the bubble diameter distribution range is preferably 10 μm to 1 mm, and the average bubble diameter is preferably 100 μm or less. Although formed, if a plurality of bonds are formed, the shape of each bubble takes a polyhedral shape due to surface tension.

  Further, such “small bubbles” are not liquid but semi-solid, and exhibit physical properties close to solid in terms of fluidity. That is, the bubbles 210 are generated from the processing liquid 201, but the generated “bubbles” themselves are not “liquid” or “gel”.

Next, the foam application part in 1st Embodiment of this invention is demonstrated with reference also to the typical explanatory drawing of FIG.
As described above, the fine foam 210 is supplied to the foam application unit 208 from the supply port at the upper part of the coating apparatus, and below the foam supply port, the supplied foam 210 is supported on the peripheral surface in the direction indicated by the arrow. An application roller 232 as a rotating application member (application means) and a stirring roller 233 for placing the supplied foam 210 on the peripheral surface of the application roller 232 are arranged.

  The coating roller 232 rotates in the direction indicated by the arrow, and the bubble 210 carried on the coating roller 232 passes through the gap with the stirring roller 233, whereby the thickness of the bubble is set. Further, a foam thickness regulating roller 234 is arranged on the downstream side (in the direction of rotation of the coating roller) with respect to the peripheral surface of the coating roller 232 so as to be adjusted to a smaller thickness. The distance between the bubble thickness regulating roller 234 and the application roller 232 is set to be smaller than the distance between the stirring roller 233 and the application roller 232.

  On the downstream side of the foam thickness regulating roller 234, there is a pressurizing unit that presses the paper 100 against the peripheral surface side of the application roller 232 at the position where the application roller 232 applies bubbles to the paper 100. A certain pressure roller 235 is arranged. The pressure roller 235 may have either a configuration that always contacts the application roller 233 or a configuration that moves in a direction that contacts the application roller 233 only when the paper 100 passes.

  Further, a cleaning means comprising a cleaning member 236 that scrapes and cleans excess foam 211 remaining on the application roller 232 after application, and a heating member 237 that heats the excess foam 212 scraped by the cleaning member 236. It has. The cleaning member 236 is disposed in contact with the application roller 232, and the excess foam 211 is scraped off by the cleaning member 236 as the application roller 232 rotates. Further, a portion where cleaning is performed by the cleaning member 236 and the heating unit 237 is referred to as a “cleaning unit”.

  In the foam application unit 208 configured as described above, the foam 210 is supplied to the peripheral surface of the application roller 232 and a film of the foam 210 is formed with a width wider than the recording medium width (paper width: width in the paper conveyance direction). Is done. This is because it is applied to the entire width direction of the paper 100. The coating roller 232 carries the foam 210 on the peripheral surface and rotates in the direction indicated by the arrow, so that the film thickness of the foam 210 on the coating roller 232 is changed to the stirring roller 233, the foam thickness regulating roller 234, and the coating roller. After the foam 210 on the peripheral surface of the coating roller 232 is adjusted to a uniform coating film thickness, the pressure is applied to the coating roller 232 and the pressure. Bubbles 310 are transferred and applied to the surface of the paper 100 conveyed in the direction of the arrow between the rollers 235. The paper 100 coated with the bubbles 210 is sent to an image forming position by the recording head unit 101.

  In this way, by applying the foam 210 to the surface of the paper 100, a small amount of application is possible by containing a large amount of air, the application can be made uniform, quick drying is improved, bleeding, show-through, A high-quality image without density unevenness can be output.

That is, by applying the treatment liquid in the form of foam, there are the following advantages (effects) compared to the liquid or mist-like treatment liquid.
(1) Since foam contains a large amount of air, it can be applied in a small amount.
(2) Since the foam is close to solid, the coating film thickness can be easily adjusted by applying and scraping, etc., and since the peelability from the coating means is good at the time of coating from the coating means to the paper, Uniform application is possible.
(3) Since water does not easily penetrate into the fibers of the paper, wrinkles and curls are unlikely to occur on the paper.

  Furthermore, the use of “foam” as the processing agent for the recording medium in this way has a special effect during recording and processing at a particularly high speed as compared with a liquid processing agent. For example, when printing on continuous paper at a high speed as in a continuous book machine, it is necessary to rotate the roller or the like at high speed in order to catch up with the recording operation.

  When such a recording speed exceeds about 100 m / min, the centrifugal force generated by the high-speed rotation of the roller becomes very large, and in the case of a liquid processing agent, the processing agent is separated from the roller surface and scattered. There is a problem that the amount applied to the film is significantly reduced. In order to solve such problems by using a liquid processing agent, it may be possible to increase the viscosity of the liquid and make it difficult to scatter from the roller surface, but such a high viscosity liquid should be applied as a thin film. In addition, the load of the liquid supply / drainage operation increases, leading to an increase in the size of the transport pump and the complexity of the apparatus.

  On the other hand, the “bubbles” generated from the processing liquid are ordinary low-viscosity liquids during transport, have a small transport load, and exhibit a semi-solid property in a foamed state on the roller. The high-speed rotation will not follow and scatter. Further, as described above, it is advantageous for thin film coating on a recording medium. Further, the remaining bubbles after application can be easily recovered as a low-viscosity liquid by defoaming by heating with a heater or the like, and all problems in high-speed application of liquid treatment agent application can be solved.

  The advantages of such foam application do not depend on the type of treatment liquid, and the same effect can be obtained. The treatment liquid preferably has an effect of suppressing paper dust, and may have an effect of changing the background color of the paper.

  Here, the bubbles 210 that have not been applied on the paper 100 from the application roller 232 remain as excess bubbles 211 on the application roller 232. That is, since the film of the bubble 210 is formed on the application roller 232 so as to be applied to the entire area in the width direction of the sheet, the bubble 210 is not applied on the sheet 100. 211 remains on the application roller 232 as it is, and when applying to a plurality of sheets, surplus bubbles 211 are also generated between sheets (between sheets).

  If such surplus bubbles 211 are left untreated, the surplus bubbles 211 are dried and the processing liquid components are fixed. When the treatment liquid component is fixed, problems such as a decrease in foam application performance (occurrence of application unevenness) and a decrease in drive system performance occur.

  Therefore, here, a cleaning member 236 for cleaning the excess bubbles 210 is provided on the application roller 232, and the application roller 232 rotates to scrape off the excess bubbles 211 for cleaning. The excess foam 211 that has been scraped off accumulates in the vicinity of the cleaning member 236, but if this is left as it is, the excess foam 212 may accumulate and adhere to the paper 100, so that the excess foam 212 is further processed. There is a need.

  However, the foam has properties such as a solid, and it is difficult to carry and process the foam as it is. Therefore, the surplus bubbles 211 are processed using the properties of the bubbles. In other words, the bubbles are aggregates of microspheres surrounding the air with a liquid thin film, and the state of the bubbles also changes due to temperature change. When the foam is heated to a high temperature, the air inside expands, so that the liquid outer wall cannot withstand the pressure from the inside and breaks and liquefies. Utilizing the nature of such bubbles.

  Therefore, heating means 237 for heating the surplus bubbles 212 is provided in the vicinity of the cleaning member 236. By heating the surplus bubbles 212 directly or indirectly by the heating means 237, the surplus bubbles 212 can be liquefied and reduced to the treatment liquid to reduce the volume.

  Here, the heating means 237 is constituted by a blade-like heater, but other means such as local heating by infrared rays or high-temperature air blowing can also be implemented.

Next, the foam application part in 2nd Embodiment of this invention is demonstrated with reference also to the typical explanatory drawing of FIG.
Here, heated hot air 238 is blown near the cleaning member 236. Thereby, the surplus foam 212 can be liquefied.

Next, the foam application part in 3rd Embodiment of this invention is demonstrated with reference also to the typical explanatory drawing of FIG.
Here, on the pressure roller 235 side, a cleaning member 236 and a heating means 237 for heating the excess foam 212 scraped by heating the cleaning member 236 are provided. That is, the surplus bubbles 211 are transferred and attached not only to the application roller 232 side but also to the pressure roller 235 side. Therefore, the surplus bubbles on the pressure roller 235 side are scraped off by the cleaning member 236 and cleaned, and the surplus bubbles scraped off are removed. 212 is liquefied by heating with the heating member 237.

Next, the foam application part in 4th Embodiment of this invention is demonstrated with reference also to the typical explanatory drawing of FIG.
Here, in the first embodiment, a recovery tray 238 is provided as a recovery liquid receiving means for receiving a liquid (reduction process liquid) reduced to a process liquid liquefied by the cleaning member 236 corresponding to the cleaning unit. The surplus bubbles (reduction treatment liquid) thus stored are stored and can be recovered through the recovery path 239. The collected reduction treatment liquid can be discarded as it is, or can be reused as the treatment liquid by returning it to the container 202 as a storage tank through the collection path 239. In this case, the solvent component of the treatment liquid that is volatilized by heating may be supplemented to adjust the treatment liquid component and then returned to the container 202.

Next, a fifth embodiment of the present invention will be described with reference to FIGS. 6 is an overall configuration diagram similar to FIG. 1, FIG. 7 is a schematic explanatory view of a foam application unit of the embodiment, and FIG. 8 is a perspective explanatory view of the application unit.
Here, as in the fourth embodiment, a recovery tray 238 that receives a liquid (reduction treatment liquid) that is reduced to a treatment liquid liquefied by the cleaning member 236 corresponding to the cleaning unit is provided, and liquefied surplus bubbles are provided. (Reduction treatment liquid) is stored so that it can be recovered through the recovery path 239. The collection tray 238 has a shape in which the bottom surface 238a is inclined, one end of the collection path 239 is connected to the lowest position of the collection dish bottom 238a, and the other end of the collection path 239 is connected to the container 202 which is a storage tank. Has been.

  Thereby, the reduction processing liquid recovered by the recovery tray 238 is returned to the container 202 through the recovery path 239 so that it can be used again as the processing liquid.

Next, the foam application part in 6th Embodiment of this invention is demonstrated with reference also to the typical explanatory drawing of FIG.
Here, a heating means 237 is provided on the lower surface of the collection dish 238. In the case of this configuration, the cleaning member 236 can be prevented from deteriorating due to heat, and the heating member can be prevented from indirectly contacting the application roller 232, so that the quality of the foam on the application roller can be easily controlled to be constant. Become. The surplus foam 212 is accumulated in the cleaning member 236, falls to the collection tray 238 by its own weight, and is liquefied by heating for the first time.

Next, the foam application part in 7th Embodiment of this invention is demonstrated with reference also to the typical explanatory drawing of FIG.
Here, heating means 237 such as a heater is disposed inside the application roller 232 so as to face the cleaning member 236. The application roller 232 is a hollow roller, and the heating unit 237 does not rotate with the rotation of the application roller 232. According to this configuration, the surplus bubbles 211 on the application roller 232 disappear at the position of the cleaning member 236 and are collected as droplets on the collection tray 238, so that the surplus bubbles 211 can be fixed on the application roller 232. Is prevented.

Next, an outline of the control unit of the image forming apparatus will be described with reference to a block diagram of FIG.
The control unit includes a CPU 801 that performs system control of the image forming apparatus, a ROM 802 that stores information such as programs executed by the CPU 801, a RAM 803 that is used as a working area, and an operation display unit that allows an operator to perform various settings. 804, various sensors 805 for detecting paper size and jam, various motors 806, I / O 807 for outputting control signals to various sensors 805 and various motors 806, and image reading device (scanner) 808 Various facsimile communication controls, including a read control unit 809 for controlling the print, a print control unit 811 for controlling the plotter unit (printing mechanism unit) 810, and a network control unit 812 for performing I / F control with the telephone line. A communication control unit 813 for performing control, a foam application control unit 814 for controlling the foam application device 200, and the like. To have.

  The foam application control unit 814 controls the foam generation unit 205 of the foam application apparatus 200 to control the generation and storage of the foam 210, the supply to the application roller 232, and the like, while turning on / off the heating unit 237 constituting the cleaning unit. Turn off control.

  The various sensors 805 include temperature / humidity detection means for detecting environmental conditions, processing liquid end detection means for detecting whether or not the processing liquid 201 is in the container 202, and the like.

A first example of control of the cleaning (defoaming) operation by the foam application control unit will be described with reference to the flowchart of FIG.
First, when the elapsed time from the previous cleaning operation reaches a predetermined time (for example, 30 minutes) (leaving for a predetermined time), it is determined whether or not the print job is being executed. A cleaning operation is performed by driving (ON) the heating means 237 of the means and heating it. On the other hand, if the print job is being executed, the cleaning operation is performed after the job is completed after the job is completed.

  The reason why the cleaning operation is performed after the end of the print job is that it is better not to perform the downtime cleaning when the user is using it, that is, to reduce the downtime.

Next, a second example of the cleaning operation control by the foam application controller will be described with reference to the flowchart of FIG.
When the power OFF instruction signal is input, the heating unit 237 of the cleaning unit is driven and controlled to perform a cleaning operation, and after the cleaning is completed, a cleaning end signal is output. In response to this, the CPU 801 of the control unit shuts down the power supply of the apparatus.

  When the power of the apparatus is turned off in this way, it is impossible to predict the time until the power is turned on next time, so that the excess foam is removed by cleaning (and defoaming) when the power is turned off. It can be prevented from being left for a long time.

  In the above embodiment, the foam application device is described as applying foam to the paper before image formation. However, the foam application device is arranged on the downstream side of the recording head unit to perform image formation. It can also be set as the structure which apply | coats a bubble on a paper. Moreover, although the said embodiment demonstrated the example which produces | generates and apply | coats foam from the liquid which can be made into foam, this invention produces | generates foam from the gel which can be made into foam, and is covered. The present invention can also be applied to an apparatus for applying to an application member and an image forming apparatus including this apparatus.

  The foam coating apparatus according to the present invention can also be applied to, for example, an electrophotographic image forming apparatus. For example, without disturbing fine particles containing a resin such as toner on a medium such as paper, and applying a foamed fixer (hereinafter referred to as “fixing bubbles”) to the medium to which the fine resin particles are adhered, After application, the resin fine particles are quickly fixed on the medium, and the present invention can also be applied to a fixing method and a fixing device, and an image forming method and an image forming apparatus in which a residual oil feeling does not occur on the medium.

  An example of application to an electrophotographic image forming apparatus will be described with reference to FIGS. 14 and 15 are enlarged explanatory views of a portion where the roller coating surface and the unfixed resin fine particles are in contact with each other in the roller coating unit, and FIG. 14 shows relative pressure applied on the contact surface between the coating roller and the recording medium. When the pressure is high, FIG. 15 shows the case where the pressure is relatively low. In addition, both the rotation direction of the application roller 1011 and the movement direction of the recording medium 1010 as the member to be applied are the arrow directions in the drawing.

  First, when the pressure on the contact surface between the application roller 1011 and the recording medium 1010 is high, the fixing bubble 1012 has a single layer structure of bubbles 1013 on the application surface of the application roller 1011 in the example shown in FIG. Therefore, the bubbles themselves are likely to adhere to the application surface of the application roller 1011 due to surface tension, and the fixing bubbles 1012 are only applied unevenly to the layer of resin fine particles (unfixed toner) 1015 on the recording medium 1010. The resin fine particles 1015 are attracted to the bubbles 1013 and are offset to the application surface of the application roller 1011.

  On the other hand, as shown in FIG. 14B, when the fixing bubble 1012 has a multi-layered bubble layer structure on the application surface of the application roller 1011, the bubbles can be embedded in the surface of the unfixed toner 1015 having irregularities. The fixing bubbles 1012 can be easily separated between the layers of the bubbles 1013, can be uniformly applied to the toner layer, and toner offset can be hardly caused.

  Therefore, when the pressure on the contact surface between the application roller 1011 and the recording medium 1010 is high, in order to prevent the unfixed toner 1015 from being offset to the application roller 1011, the average size of the bubbles generated in advance is set. If the film thickness of the fixing foam layer on the application roller 1011 is controlled so as to be the thickness of the plurality of bubble layers so that the bubble layer becomes a plurality of layers, the measurement is always performed on the application roller 1011. A fixing foam layer composed of a plurality of bubble layers is formed, and toner offset can be prevented.

  When the pressure on the contact surface between the application roller 1011 and the recording medium 1010 is low, the fixing bubble 1012 has a single-layer structure of bubbles 1013 on the application surface of the application roller 1011 as shown in FIG. Therefore, bubbles easily adhere to the surface of the unfixed toner 1015 having irregularities, the bubble layer is peeled off from the surface of the application roller 1011, and the fixing bubbles 1012 are applied to the unfixed toner 1015.

  On the other hand, as shown in FIG. 15B, when the fixing bubble 1012 has a multi-layered bubble layer structure on the application surface of the application roller 1011, the bubbles 1013 are strongly coupled to each other, so that the bubbles 1013 are placed on the application roller 1011 side. On the contrary, the unfixed toner 1015 adheres to the air bubble 1013, and as a result, the unfixed toner 1015 is offset on the surface of the application roller 1011.

  Therefore, when the pressure on the contact surface between the coating roller 1011 and the recording medium 1010 is low, the average size of the bubbles is measured in advance, and a fixed bubble having a single-layer bubble layer structure is formed on the coating roller surface. By controlling the thickness of the fixing foam layer as described above, a fixing foam film having a single-layer bubble layer structure is formed on the coating roller, and toner offset can be prevented under high pressure conditions. Further, in order to prevent the unfixed toner 1015 from being offset to the application roller 1011, if the bubble layer on the application roller 1011 is too thick, the bubble layer flows at the contact portion between the application roller 1011 and the recording medium 1010. Since the toner particles move along the flow, and a problem of flowing of the image occurs, it is preferable to control the film thickness of the fixing foam layer within a range in which fluidity does not occur.

  In this way, by controlling the film thickness of the fixing foam layer according to the size and pressure of the bubbles contained in the fixing foam, toner offset and image flow to the contact application means such as the application roller can be prevented. In addition, fixing by extremely minute application can be made possible.

  That is, using a softening agent that softens the resin fine particles by dissolving or swelling at least a part of the resin fine particles, the fixing solution is applied to the resin fine particles on the medium by contact coating means, and the resin fine particles are fixed to the medium. When the fixing solution is applied to the surface of the fine resin particles on the medium, the fixing solution is in the form of bubbles containing bubbles by coating the fine particles in contact with the fine particles. By controlling the film thickness of the layer according to the applied pressure, it is possible to prevent toner offset and image flow to a contact application means such as an application roller, and to enable fixing by extremely minute application. Further, the resin fine particles are highly effective for the toner fine particles used in the electrophotographic technology, and offset and image flow can be prevented by controlling the film thickness of the fixing foam layer according to the layer thickness of the resin fine particles.

100: Recording medium (paper)
DESCRIPTION OF SYMBOLS 101 ... Recording head unit 102 ... Conveyor belt 103 ... Paper feed tray 200 ... Foam coating apparatus 201 ... Processing liquid (foaming liquid or gel or liquid and gel)
DESCRIPTION OF SYMBOLS 205 ... 1st foam production | generation part 206 ... Foam conveyance path | route 207 ... 2nd foam production | generation part 208 ... Foam application part 210 ... Foam 232 ... Application roller 235 ... Pressure roller 236 ... Cleaning member 237 ... Heating means 238 ... Collection tray 239 ... Collection route

Claims (5)

Image forming means for forming an image on a recording medium;
A foam application means for applying at least one of a liquid and a gel to the recording medium or an intermediate member for application to the recording medium,
The foam applying means is
Application means for applying the foam;
An image forming apparatus, comprising: a cleaning unit that heats and cleans excess foam remaining without being applied by the applying unit.   The cleaning unit includes: a cleaning member that cleans excess bubbles on the application unit or a pressurizing unit that pressurizes the recording medium or the intermediate member facing the application unit; and a heating unit that heats the cleaning member. An image forming apparatus comprising:   The image forming apparatus, wherein the heating unit is a unit that blows a heated airflow onto the cleaning member.   A storage tank for storing the processing liquid capable of generating the foam, and a recovery means for recovering the liquid stored in the storage tank from the foam returned to the processing liquid by being heated by the heating means of the cleaning means. An image forming apparatus comprising: In a foam application device for applying foam to a member to be coated by foaming at least one of liquid and gel,
Application means for applying the foam;
And a cleaning means for heating and cleaning excess foam remaining without being applied by the applying means.

Images