JP2010158794A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem such as insufficient supply or oversupply of foam, oozing due to surplus foam, faults due to spreading to other parts in an applying device, wasting of a treatment liquid, unnecessary adhesion to a recording material, and uneven application of foam in an image forming apparatus which has a foam applying means for applying the foam as a treatment agent or fixing agent to the recording material. <P>SOLUTION: The image forming apparatus of an inkjet system includes the foam applying device 200 which applies the foam turned from at least one of liquid and gel as the treatment agent or fixing agent to a recording medium. The foam applying device 200 has foam generating means 205 and 207. The foam generated by the foam generating means is supplied via a spreading part 250 to a foam storing part 237 of the applying means 208. Partition wall members of a pair 270a and 271a as a supply width variable means which can change a supply width in a direction orthogonal to a conveyance direction of a paper 100 are made synchronously movable according to a paper width by a lead screw 272 in the foam storing part 237. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to an image forming apparatus such as a copying machine, a printer, a facsimile, a plotter, and a printing apparatus that employs an ink jet recording method, and a multifunction machine including one of these, and more particularly, bleeding (feathering, bleeding, etc.). The present invention relates to an image forming apparatus that applies a liquid (or gel or both) that can be in a foam state having a function as a set agent that suppresses and enables high-density and high-saturation image formation to be applied to a recording medium in the form of fine bubbles.
The present invention can be applied to inkjet technology such as textile printing and surface treatment (liquid application of ink permeability modifier, gloss material, coating material, etc.) apparatus.

As an image forming apparatus such as a printer, a facsimile machine, a copying machine, or a multifunction machine of these, for example, a recording head composed of a liquid ejection head that ejects liquid droplets of a recording liquid is used, and a recording medium (hereinafter also referred to as “paper”). However, the material is not limited, and a medium, a recording medium, a transfer material, a recording paper, etc. are also used synonymously, and droplets are attached to the paper to form an image (recording, printing, printing). , Printing is also used synonymously).
The “image forming apparatus” means an apparatus that forms an image by landing droplets on a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics or the like.
Further, “image formation” not only means that an image having a meaning such as a character or a figure is imparted to the medium, but also that an image having no meaning such as a pattern is imparted to the medium.
Further, the “recording liquid” is not limited to ink, and may be any liquid that can form an image in the above sense and can be formed into droplets upon ejection.

In such a liquid discharge type image forming apparatus, since a recording liquid containing color material (hereinafter referred to as “ink”) is formed into droplets to form an image, the dots formed by the droplets are disturbed in a whisker shape. Feathering, color bleed that causes colors to blur when the ink droplets of different colors are struck on the paper adjacent to each other, lack of color (density), show-through, glossiness, fixability Such a problem may occur.
Further, in addition to the initial quality problem that it takes time for the droplets on the paper after printing to dry, there are problems relating to fastness such as water resistance, light resistance, scratch resistance, and ozone resistance.

Conventionally, as described in Patent Document 1, a pretreatment liquid that reacts with ink to prevent bleeding is applied with an application roller, or as described in Patent Document 2, the pretreatment liquid is liquid. For example, the liquid is ejected in a mist form from the ejection head.
Patent Document 3 describes that the treatment liquid for improving the fixing property of the ink is applied before or after ink printing, and is not limited to the pretreatment, and there is a case where a posttreatment is performed.
However, as described in Patent Documents 1 to 3, in the method in which the pretreatment liquid or the posttreatment liquid is spouted by the application roller or the liquid discharge head, application unevenness occurs (first problem) and the liquid For this reason, there is a problem in the quick drying property after reacting with the ink on the paper. In particular, the paper is likely to be wrinkled or curled or bent, so that jamming is likely to occur (second problem).

JP 2002-137378 A Japanese Patent Laying-Open No. 2005-138502 JP 2003-205673 A JP 2008-94055 A

In order to solve the above-mentioned problems, the present applicant has proposed a technique for applying a treatment liquid in a foam state in Japanese Patent Application No. 2007-178698.
The “bubble state” refers to a state in which a large amount of bubbles are dispersed in the liquid and the liquid is compressible. For example, the following advantages can be obtained in the foam state as compared with the liquid or mist processing liquid.
(1) Since the foam contains a large amount of air, a small amount of liquid can be applied.
(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 when applied 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.

The above advantages do not depend on the type of treatment liquid, and the same effect can be obtained. The treatment liquid desirably has an effect of suppressing paper dust, and may have an effect of changing the background color of the paper.
However, in the foam coating apparatus that applies the treatment liquid to the recording medium with foam, if the increase or decrease of the foam supply amount according to the width of the recording medium or the control of the application width is not performed, the supply of foam is insufficient or excessive. It arises (third problem).
If the coating area is equal to or larger than the recording material width, surplus bubbles will ooze out from the opposite ends of the recording medium to the surface opposite to the coating surface (fourth problem).
The treatment liquid adhering to the unnecessary application area spreads to another part in the application apparatus (fifth problem).
The generation of these unnecessary bubbles wastes the processing liquid (sixth problem).
By not controlling the bubble supply amount according to the recording medium width, if the bubble supply amount becomes excessive, it leaks into and out of the coating device, contaminates the inside of the device, or unnecessarily adheres to the recording material. (Seventh problem).
Moreover, when the amount of foam supply becomes insufficient, uneven foam application occurs (eighth problem).
In Patent Document 4, since the processing liquid is always applied to both sides of the recording medium, even when printing on only one side, for example, it is not necessary to apply the processing liquid originally. The treatment liquid is applied even to the opposite surface, and there is a problem that the treatment liquid is wasted to an unnecessary area, which is common to the sixth problem.
Also, there is a risk of inducing undesired problems in terms of transportability (skew, slip, resist, curl, liquid transfer contamination to rollers, transfer of dirt from rollers, etc.) due to wet processing liquid on both sides of the paper simultaneously. (9th problem).

  SUMMARY An advantage of some aspects of the invention is that it provides an image forming apparatus that can solve the above-described problems.

  In order to achieve the above object, according to the first aspect of the present invention, in an image forming apparatus for forming an image on a recording medium, the liquid and gel are applied to the recording medium or an intermediate member applied to the recording medium. A foam applying means for applying at least one of the foamed foam as a processing agent or a fixing agent, the foam applying means comprising: a foam generating means for generating the foam; and the foam as a recording medium or the intermediate member. And a supply width variable means capable of changing a supply width of the bubbles from the bubble generating means to the application means in a direction perpendicular to the conveyance direction of the recording medium. Features.

  According to the second aspect of the present invention, in the image forming apparatus for forming an image on the recording medium, at least one of the liquid and the gel is foamed with respect to the recording medium or the intermediate member to be applied to the recording medium. Foam application means for applying foam as a processing agent or fixing agent, the foam application means, foam generation means for generating the foam, application means for applying the foam to the recording medium or the intermediate member, Application width varying means capable of changing the application width of the bubbles from the bubble generating means to the application means in a direction orthogonal to the conveyance direction of the recording medium.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect, the foam generating means extends the foam in the supply width or the application width direction when supplying the foam to the application means. It has the part.
According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect, a bubble storage part is formed between the extension part and the application means within the supply width area, and the supply width variable means It has a pair of partition members that can move the foam reservoir in the supply width direction, and the supply of foam from the foam generating means to the foam reservoir is narrower than the minimum width of the movable range of the pair of partition members It is made from a supply port.

According to a fifth aspect of the present invention, in the image forming apparatus according to the third aspect, a bubble storage portion is formed between the extension portion and the coating means within the coating width region, and the coating width varying means is It has a pair of partition members that can move the foam storage part in the application width direction, and the supply of foam from the foam generation means to the foam storage part is narrower than the minimum width of the movable range of the pair of partition members It is made from a supply port.
According to a sixth aspect of the present invention, in the image forming apparatus according to the fourth or fifth aspect, an area in the extension portion follows the movement of the pair of partition members between the pair of partition members and the supply port. An extending portion diaphragm member is provided that changes the region to an appropriate region corresponding to the supply width or the coating width defined by the pair of partition members.

According to a seventh aspect of the present invention, in the image forming apparatus according to any one of the fourth to sixth aspects, a sealing means is provided for bringing a region surrounded by the pair of partition wall members in the foam reservoir into a closed space state. It is characterized by that.
According to an eighth aspect of the present invention, in the image forming apparatus according to the seventh aspect, the sealing means is provided so as to face the pair of partition members, and is displaced in the height direction of the partition members by increasing or decreasing bubbles. When the pair of partition members are set to the minimum width position, the first and second flaps that intersect so as to overlap the height direction of the partition members and the foam generating means side are provided, And a third flap that can be displaced in a height direction of the partition wall member by pressing and pressing the first and second flaps from above with their own weight.

According to a ninth aspect of the present invention, in the image forming apparatus according to any one of the first to eighth aspects, a recording medium width information acquiring unit that acquires width size information of the recording medium in the supply width direction, or a recording medium Recording medium application area information acquisition means for acquiring application area size information in the application width direction of the recording medium width information or application area size information from the recording medium width information acquisition means or the recording medium application area information acquisition means. Based on this, the supply width or the coating width is changed.
According to a tenth aspect of the present invention, in the image forming apparatus according to the ninth aspect, a command value for a supply amount of bubbles required according to the width size information or the application region size information and the number of print commands is a control table. And supplying the foam by the foam generating means is feedforward controlled.

According to an eleventh aspect of the present invention, in the image forming apparatus according to any one of the fourth to tenth aspects, a gap between the partition member and the coating unit in the supply width varying unit or the coating width varying unit is It is set to the dimension narrower than the average diameter of the bubble in the said bubble storage part.
According to a twelfth aspect of the present invention, in the image forming apparatus according to any one of the fourth to fourth aspects, a gap is substantially provided between the partition member and the coating unit in the supply width varying unit or the coating width varying unit. It is characterized by no.

According to a thirteenth aspect of the present invention, in the image forming apparatus according to the eleventh or twelfth aspect, the contact angle when the coating member side of the partition wall member is in contact with the foam is a liquid is 90 degrees or more. It is characterized by being made of a material having water repellency or a material having a surface subjected to water repellency treatment.
According to a fourteenth aspect of the present invention, in the image forming apparatus according to any one of the fourth to tenth aspects, a gap is substantially provided between the partition member and the coating unit in the supply width varying unit or the coating width varying unit. The partition member is formed of an elastic body or a flexible structure on the coating means side.
According to a fifteenth aspect of the present invention, in the image forming apparatus according to any one of the fourth to tenth aspects, a gap is substantially provided between the partition member and the coating unit in the supply width varying unit or the coating width varying unit. In addition, the application means side of the partition member is made of an absorber having absorbency or capillary force with respect to the liquid when the bubbles are in a liquid state.

According to the present invention, it is possible to apply the foam only to the paper size in the foam application device and the application position corresponding to the application area, so that not only the useless consumption of the foam is reduced, but also the foam is wide, for example. If transferred to the area, the third to ninth problems such as the treatment agent oozing from the edge of the paper to the surface opposite to the application surface can be solved.
By supplying the foam from a region narrower than the minimum width of the movable range of the partition wall member, the foam is spread evenly and promptly in the foam reservoir so that the foam flow spreads every corner. It is possible to carry out the distribution of water and to supply a stable foam.
By providing a sealing means that closes the region surrounded by the partition wall member in the foam storage part, it is possible to suppress the leakage of the foam to a region other than the desired width of the desired foam storage unit.

It is possible to solve the above-mentioned third to ninth problems due to the excessive supply amount of bubbles and the leakage from the bubble storage part, and the problem of causing coating unevenness due to shortage.
With the shield structure, it is possible to reliably prevent bubbles from leaking from the bubble storage portion even if the width between the partition members is varied.
Even when there is no gap between the rollers and the partition member, when the bubbles are slightly liquefied in the contact portion, it always flows downward due to the action of trying to accumulate downward due to gravity, It becomes a liquid film, lubricates the friction portions on both the partition walls and the surface of each roller, has an action of preventing solid contact, and can prevent wear.
Furthermore, if the partition wall material is made of a water-repellent material, the treatment agent liquefied on the wall surface of the partition wall does not stick, but quickly flows downward due to the action of gravity. It is done.
The processing liquid that has been liquefied by contacting the rollers at the bottom of the partition also generates shearing force in the liquid, so it has the effect of foaming again, and it is applied to the paper in a liquefied state, thereby significantly increasing the concentration distribution of the coating. It is possible to reduce defects that are damaged.

1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. It is a figure which shows the structure of the application means of a foam application apparatus, (a) is a left view, (b) is an upper side view. It is a figure which shows the principal part of a bubble production | generation means. It is a perspective view which shows a pair of partition member. It is an upper side view of an application means when a partition member is set to the maximum width. It is a left view which shows the supply state of the bubble in the state in which the partition member was set to the maximum width. It is an upper side view of an application means when a partition member is set to the minimum width. It is a left view which shows the supply state of the bubble in the state in which the partition member was set to the minimum width. It is a figure explaining the bubble spill prevention function by the sealing means (flap) in a bubble storage part. It is a figure explaining the bubble spill phenomenon when there is no sealing means in a bubble storage part. It is a flowchart of processing agent application control. Max. It is a flowchart of the subroutine of a width x length correspondence process. It is a flowchart of a subroutine of size A width × length correspondence processing. It is a flowchart of a subroutine of size N width × length correspondence processing. Min. It is a flowchart of the subroutine of a width x length correspondence process. It is a flowchart of processing agent application control. It is a system control block diagram. It is a figure which shows the example whose contact part clearance gap between a partition member and rollers is narrower than the average diameter of a bubble, (a) is a front view, (b) is a longitudinal cross-sectional view which shows the shield function. It is a figure when there is no contact part clearance gap between a partition member and rollers, (a) is a front view, (b) is a longitudinal cross-sectional view which shows the shield function. It is a figure which shows the example which a contact part of a partition member and rollers consists of an elastic body or a structure which has flexibility, (a) is a front view, (b) is a longitudinal cross-section which shows the shield function in the case of an elastic body FIG. 4C is a longitudinal sectional view showing a shielding function in the case of a flexible material. It is a figure which shows the example which consists of a structure which has the capillary force of a partition member and rollers, (a) is a front view, (b) is a longitudinal cross-sectional view which shows the shield function.

Embodiments of the present invention will be described below with reference to the drawings.
First, an example of an image forming apparatus including a foam application device as a foam application unit according to the present embodiment 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 droplets onto a paper 100 that is a recording medium, a belt conveyance device 102 that conveys the paper 100, and the paper 100. A foam is applied to the paper 100 that is a member to be applied on the upstream side in the paper transport direction from the recording head unit 101, and a paper discharge tray 104 that discharges the paper 100 on which an image is formed. The foam coating device 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 (C) and recording heads 101y, 101m, 101c, and 101k that discharge ink droplets as recording liquids of black (K) are provided. Note that the recording head can be mounted on the carriage as a serial type image forming apparatus.
The belt conveyance device 102 is configured such that a conveyance belt 102 a that is an endless belt is looped around a conveyance roller 121 and a tension roller 122. For holding the paper 100 on the conveyance belt 102a, for example, electrostatic adsorption, adsorption by air suction, or other known conveyance means can be used.
The paper 100 stored in the paper feed tray 103 is separated one by one by a pickup roller 131, fed by a pair of transport rollers 132, transported through a transport path 135 by a pair of transport rollers 133 and a pair of registration rollers 134, and foamed. After the foam application is performed by the application device 200, it is fed onto the belt conveyance device 102 and held.
Each color droplet is ejected from the head unit 101 while being conveyed by the belt conveying device 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 foam application apparatus 200 includes a container 202 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 a foam state, and the container 202. A pump 203 that pumps the processing liquid 201 from the first, a first foam generating unit 205 that forms a bubble 210a from the processing liquid 201 supplied by the pump 203 via the supply path 204, and forms a part of the foam generating means; The foam supply path 206 that is a path for sending the foam 210a from the one foam generation unit 205 and the foam 210a conveyed through the foam supply path 206 are sheared a plurality of times to form small bubbles (small bubbles) 210 (b, c, d). When the foam is supplied to the second foam generation unit 207 that forms part of the foam generation unit, the foam application unit 208 as an application unit that applies the foam 210 to the paper 100, Recorded And a spreader portion 250 such that the spreader in the width direction perpendicular to the conveying direction of the body.
In the second bubble generation unit 207, net-like bubble refining members 241a, 241b, and 241c that shear the bubbles 210a generated by the first bubble generation unit 205 are arranged, and these are directed toward the bubble application unit 208. The mesh is finely set in stages. The bubbles 210a are sheared every time they pass through these bubble refining members 241a, 241b, 241c, and after passing, become bubbles with a small diameter due to surface tension. This bubble reduction (miniaturization) is performed in stages. In FIG. 3, it has shown by the bubble refinement | miniaturization member 241a, 241b, 241c.
As shown in FIG. 3, the extension part 250 has a manifold part 251 having a predetermined volume and a slit-like outlet 252.
In this figure, the extension diaphragm 260 is omitted for convenience.

Here, the “bubble” is a liquid in which a gas such as air is rounded and formed by the surface tension of the liquid enclosing the gas, and can hold a three-dimensional shape for a certain period of time. . Hereinafter, it is also referred to as “foam”.
The foam having such shape-retaining properties desirably has a bulk density of 0.05 g / cm ³ or less, a foam diameter distribution range of 10 μm to 1 mm, and an average foam diameter of 100 μm or less. In addition, although a bubble is formed in a round shape by itself, when a plurality of bubbles are combined, the shape of each bubble takes a polyhedral shape due to surface tension.
The “bubbles” thus formed are not liquid but semi-solid, and exhibit physical properties close to solid in terms of fluidity.

The refined bubbles are supplied from the right direction in FIG. The foam supplied through the foam supply path 206 that is a pipe path is extended (diffused) in the manifold section 251, passes through the outlet 252, and is supplied to the foam application section 208.
Here, the treatment liquid 201 that can be in a foam state 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 the 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.

As shown in FIG. 1, the first foam generation unit 205 supplies high-pressure air from the high-pressure air supply unit 221 to the processing liquid 201 in the foam generation container 220 via the high-pressure air supply path 223. Bubbles 210 are generated.
When the foam 210 is generated and filled in the foam generation container 220, the foam 210 is supplied toward the foam application unit 208 via the foam supply path 206 by the pressure. The pump 203 closes the supply path 204 so that the bubbles 210 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 small bubbles 210d supplied from the outlet 252 of the foam spreading section 250 are stored in the foam storage section 237 between the application roller 232 and the foam transport roller 233 constituting the application means (foam application section 208) as illustrated. The
Also, the foam stored in the foam storage section 237 spreads in the axial direction of the roller when the foam transport roller 233 and the application roller 232 (which can also be a foam generation application roller described later) are in contact with each other and rotated. To have) properties. In order to keep the foam only in a necessary region by stopping the spreading action, a supply width varying means or a coating width varying means described later is required.

Instead of the application roller 232, a foam generation application roller 234 having a porous elastic surface layer may be substituted. The difference will be described below.
The application roller 232 applies the foam in the foam storage unit 237 to the paper 100 as it is by applying pressure from the pressure roller 235, whereas the foam generation application roller 234 has a capillary force regardless of whether it is a closed cell or an open cell. When the surface layer made of an elastic material having a contact with the foam in the foam reservoir 237, even if the foam treatment agent has already been foamed, it is again sucked in by a capillary force such as microcells on the roller surface layer. Although it is pushed out by the pressure roller 235, the processing agent component of a small amount of bubbles confined in the roller bubbles after slightly sucking the bubbles in the original bubble storage portion 237 is divided into new finer bubbles. The so-called foam shear effect has the effect of generating finer bubbles.
Therefore, in the case of this foam generation application roller, since the foam is generated to an area slightly wider than the target foam application area (width), the application range to the paper 100 is slightly expanded, but the foam itself It is expected that the fineness will become fine according to the mechanism described above.

As shown in FIGS. 1 and 2, the foam storage section 237 includes a front partition as a pair of partition members provided on both ends of the transport path (both ends in the roller axis direction orthogonal to the sheet transport direction). 270a and a rear partition 271a, each of which has a lead screw 272 provided with symmetrical leads at the center in the width direction of the transport path, and moves in the opposite direction in the width direction according to the rotation. It has a structure.
As shown in the drawing, the lead screw 272 is driven by a screw feed method including a gear 273 at the end of the lead screw 272, a pinion 274 engaged therewith, and a motor 275 that rotates the pinion 274.
As the type of the motor 275, it is appropriate to use a stepping motor capable of rotating a desired rotation angle with high accuracy. However, the motor 275 is not limited to this as long as accuracy is ensured according to the rotation angle command value. Also good.

As shown in FIG. 2B, when the front partition 270a and the rear partition 271a expand to the vicinity of the maximum width, a home position sensor (hereinafter referred to as “HP sensor”) that contacts the outside of the rear partition 271a. 276) and is used as a sensor for detecting the absolute position for the initialization operation for detecting the initial position of the motor 275.
As shown in FIGS. 1 and 4, the portions of the front partition 270a and the rear partition 271a that are in contact with the bubble transport roller 233 and the pressure roller 235 have an arc shape that follows the outer shape of each roller. Furthermore, Teflon (registered trademark), high-density polyethylene, etc. are affixed to this part to ensure sliding characteristics (reduction of friction coefficient), or an O-ring function is provided to ensure sealing performance. By using the elastic material having the shape, it is possible to reliably retain the foam while preventing wear caused by sliding between the foam transport roller 233 and the pressure roller 235.

As shown in FIG. 4, the front partition 270a and the rear partition 271a are provided with a front insertion portion 270b and a rear insertion portion 271b that extend to the inside of the outlet 252, respectively. A funnel-shaped extending part diaphragm 260 made of an elastically deformable material such as rubber or elastomer is provided between the outer side in the width direction and a supply port 206a as an end of the foam supply path 206. (See FIGS. 1 and 2B).
As a result, the closed partition space is maintained in any width dimension set for the front partition wall 270a and the rear partition wall 271a, and at least a region sandwiched between the front partition wall 270a and the rear partition wall 271a. The small bubbles 210d are prevented from spilling out from the bubble reservoir 237 to the outer region.

As shown in FIG. 4, on the inner side in the width direction of the front partition 270a and the rear partition 271a, a first flap (side flap) 280a is a hinge 280b, and a second flap (side flap) 281a is a hinge 281b. It is provided so as to be able to swing in the vertical direction (height direction of the partition wall member).
A third flap (center flap) 282a extending in a direction perpendicular to the first and second flaps on the upper surface of the outlet 252 at the center in the width direction of the foam reservoir 237 is vertically moved by a hinge 282b. Is provided to be swingable.
These flaps constitute a sealing means for closing a region surrounded by the pair of partition members (the front partition 270a and the rear partition 271a) in the foam storage section 237.
With this configuration, the small bubbles 210d are prevented from spilling from the upper side of the bubble storage part 237 to the outer region.

The width dimension of the three flaps has the following characteristics.
As shown in FIG. 2B, the width dimension of the third flap 282a is 100 mm, which is exactly equal to the minimum sheet width conveyed by the image forming apparatus.
The width dimension of the third flap 282a is the same as the inner dimension when the first flap 280a and the second flap 281a are set to the minimum sheet width, and is arranged at the same position.
The first flap 280a and the second flap 281a have a U-shaped cross section that opens downward as shown in FIG. 1 and the like (not shown in FIG. 4). These flaps are slightly dimensioned so that one of them is mounted on the other when the minimum paper width is set, with the attachment positions to the hinges being slightly shifted in the vertical direction.
The lower limit positions of the first flap 280a and the second flap 281a are set so as to hang down slightly.
The third flap 282a presses the first flap 280a and the second flap 281a with its own weight.

The width dimension of the first flap 280a and the width dimension of the second flap 281a are also 100 mm, and these flaps and the third flap 282a are triplely overlapped in the vertical direction. Thereby, even if the inner dimension of the front partition 270a and the rear partition 271a is set to the minimum width size (100 mm), interference between the flaps does not occur.
When the width dimension of the front partition 270a and the rear partition 271a is set to an inner dimension 297 mm corresponding to the maximum sheet width, the first flap 280a and the second flap 281a are also expanded with each other. Since both of them are 100 mm, the third flap 282a is provided with a portion overlapped by 1.5 mm, so that the effect of preventing the leakage of bubbles can be obtained.

FIG. 5 shows an upper side view when the width dimension of the front partition 270a and the rear partition 271a is set to the inner dimension 297 mm corresponding to the maximum sheet width. In this state, the three-stage state of the small bubbles 210d accumulated in the bubble storage unit 237 is individually shown in FIG. 6 as a left side view.
FIG. 6 (a) shows a state where the foam is small, FIG. 6 (b) shows a state immediately after the foam is filled in the foam reservoir 237, and FIG. 6 (c) shows a state immediately before the foam is further supplied and overflowed. Indicates the state.
When the amount of bubbles increases, the first flap and the second flap are pushed up by the pressure and displaced upward.
FIG. 7 shows an upper side view when the width dimension of the front partition 270a and the rear partition 271a is set to an inner dimension of 100 mm corresponding to the minimum sheet width. In this state, the three-stage state of the small bubbles 210d accumulated in the bubble storage unit 237 is individually shown in FIG. 8 as a left side view.
FIG. 8 (a) shows a state where the foam is small, FIG. 8 (b) shows a state immediately after the foam is filled in the foam reservoir 237, and FIG. 8 (c) shows a state immediately before the foam is further supplied and overflowed. Indicates the state.

The third flap 282a presses the first flap 280a and the second flap 281a with its own weight from the upper side in any of the above-described three stages, and thereby the first flap and the second flap due to the increase in the bubbles. The foam is prevented from leaking due to the sudden rise of the flap, and the uniform diffusion (extension) of the foam in the roller axial direction is promoted. That is, the function of leveling the foam supplied from the supply port 206a in the roller axial direction is obtained by the pressing action including the first flap and the second flap by the third flap.
The supply port 206a is a connection part between the bubble supply path 206 and the extending part 250, and the width (diameter) thereof is narrower than the minimum width of the movable range of the front partition 270a and the rear partition 271a. Thereby, since the flow of foam spreads every corner, a stable foam distribution function is obtained, and stable foam supply can be performed.

As shown in FIG. 1, a cleaning blade 236 having an arcuate cross section is provided along the downstream end of the front partition and the rear partition in the sheet conveyance direction. The cleaning blade 236 has a length extending over the entire roller axial direction, and is supported by a side plate (not shown) of the foam application unit 208. One end (lower end) of the cleaning blade 236 is in contact with the surface of the application roller 232 in the counter direction, and the residue on the application roller 232 is removed.
As described above, since the cleaning blade 236 has a length extending in the roller axis direction, it is possible to cover a portion of the foam reservoir 237 that cannot be covered by the first flap and the second flap, and prevent foam leakage. It contributes to.
A fixed partition wall 238 having an angled cross section is provided along the upstream end of the front partition wall and the rear partition wall in the sheet conveyance direction. The fixed partition wall 238 has a length extending over the entire roller axial direction, and is supported by a side plate (not shown) of the foam application unit 208. One end (lower end) of the fixed partition wall 238 is in contact with the surface of the foam transport roller 233 to prevent the foam from leaking from the foam reservoir 237.
The fixed partition wall 238 may be supported on the lower surface of the outlet 252 of the extending portion 250 or may be formed integrally with the lower surface of the outlet 252.

As described above, the third flap 282a is provided on the top surface of the foam reservoir 237, and the first flap 280a and the second flap 281a are pressed from the upper side to thereby distribute the foam in the foam reservoir 237. Has the effect of being kept even.
Depending on the amount of small bubbles 210d stored in the application roller 232 or the bubble storage part 237 between the bubble generation application roller 234 and the bubble conveyance roller 233, the third flap is stored around the hinge 282b. Even if the distribution of bubbles is uneven, as shown in FIG. 9, the bubbles are evenly distributed by pressing from above.
If these three flaps are not present, the bubble distribution becomes non-uniform as shown in FIG. 10, and in the worst case, the bubbles may leak from the bubble storage portion 237.
In the drawing, the distribution of bubbles in the cross-sectional direction (height direction of the partition wall) is described, but the same phenomenon can occur in the longitudinal direction (the roller axis direction) of the bubble storage portion 237.

When the application roller 232 or the bubble generation application roller 234 and the bubble transport roller 233 are rotated in the rotation direction shown in FIG. 9, the stored bubbles are always placed in a stirring state, so that the bubbles always have a constant cell diameter.
Here, structural differences and functional differences between the application roller 232 and the foam generation application roller 234 will be described.
The structure of the application roller 232 has a smooth surface or a very fine fine-grained surface. Even if the material is an elastic body, the foam material component does not permeate into the material and adheres to the surface. In order to transfer the bubbles to the surface of the paper 100, it has a function of adhering and conveying.
On the other hand, the structure of the foam generation application roller 234 is made of a foamed elastic material having a capillary force regardless of whether the material is a closed cell or an open cell, and when the surface layer comes into contact with the foam in the foam reservoir 237, the foam is already foamed. Even if the foam treatment agent is, it is slightly sucked by the capillary force of the microcell or the like by the polishing surface of the foam on the roller surface layer, and then pushed out by the pressure roller 235 again. A small amount of foam treatment agent confined in the roller bubbles after sucking in the bubbles a little is divided into finer bubbles, so there is an action to generate finer bubbles due to the so-called foam shear effect. In the case of this roller, since bubbles are generated to a region slightly wider than the target bubble application region (width), the application range to the paper 100 may be slightly expanded. The fineness of it is expected that finer as the mechanism described above.

The function of the foam generation application roller 234 corresponds to the application means described in claim 1. That is, it means that finer bubbles are generated even after the bubbles are supplied to the bubble generation application roller 234, and thus the function of the partition means the width to be supplied to the bubble generation application roller 234. Therefore, the pair of partition walls when the foam generation application roller 234 is used functions as a supply width varying unit.
On the other hand, the function of the application roller 232 corresponds to the application means described in claim 2. That is, after the foam is supplied to the application roller 232, it means that the application is performed while maintaining the state of the bubble as it is, and the function of the partition means the width of application to the paper 100 by the foam application roller 232. ing. Accordingly, the pair of partition walls when the application roller 232 is used functions as an application width varying unit.

As described above, the use of the “bubble” type processing agent for the recording medium has a particularly advantageous effect at the time of recording / processing at a high speed as compared with the 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 extremely large, and the liquid processing agent is separated from the roller surface and scattered, which is applied to the recording medium. There is a problem that the amount to be reduced is significantly reduced.
In order to solve such problems with 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. However, it is difficult to apply such a high viscosity liquid as a thin film. In addition, the load of the liquid supply / drainage operation is large, leading to an increase in the size of the transport pump and the complexity of the apparatus.
On the other hand, “foam” -like treatment agent is a normal low-viscosity liquid during transportation and has a small transportation load, and also exhibits semi-solid properties in a foamed state on the roller. 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.

Next, a series of processing operation examples of processing agent application control corresponding to the paper size in response to a print command in the image forming apparatus will be described with reference to flowcharts shown in FIGS.
FIG. 11 is a main routine, and FIGS. 12 to 15 are subroutines thereof. In this flowchart, the application width and application length of the processing agent according to the paper size are mentioned.
In the conditional branch (S-01) for presence / absence of printing command, if No (hereinafter N), it returns to the original, and if Yes (hereinafter Y), the distance between the front partition 270a and the rear partition 271a is set to the maximum width (for example, The operation of expanding to A3 width (297 mm) shown in FIG. 2A is performed by starting the motor 275 (S-02).
When the HP sensor 276 detects the outer wall surface of the rear partition 271a, it is recognized as HP (S-03).
By obtaining this signal, it can be set by commanding the number of rotations of the motor 275 up to an arbitrary width dimension (in the case of a stepping motor), so that the initialization of the width drive control is executed. Become.

Next, the paper size information to which the processing agent is to be applied is acquired based on the print command and input information from the operation unit by the operator (S-04).
The width size of the paper size information acquired in (S-04) is Max. If it is (maximum width), a conditional branch is made (S-05). If Y, the process goes to a subroutine (S-08). If N, the next step is executed.
The width size of the paper size information acquired in (S-04) is Max. Conditional branching is made as to whether the “A width” is smaller than the (maximum width) by the dimension a (S-06). If Y, the process proceeds to a subroutine (S-09), and if N, the next step is executed.
The width size of the paper size information acquired in (S-04) is Max. Conditional branching is made as to whether the “N width” is smaller than the (maximum width) by n dimensions (S-07). If Y, go to the subroutine (S-10), and if N, execute the next step.
Here, the a dimension (“A width”) of (S-06) and the “n dimension” and “N width” of (S-07) are general values, and are actually A4 horizontal, B5 horizontal,. -It may be a specific dimension such as a postcard size, or may be a "width dimension" obtained by applying a number of unequal divisions from a to n dimensions, or an equal division.
Min. When the condition branch of “width dimension” closest to (minimum width) is N in (S-07), the width dimension of the paper size information acquired in (S-04) is Min. It is recognized as (minimum width), and the corresponding subroutine (S-11) is executed.
Next, a conditional branch is made depending on the presence or absence of a print instruction for the next page (S-12). If Y, the process loops to (S-02). If N, the main flow ends.

Next, the subroutines of FIGS. 12 to 15 will be described individually.
FIG. 12 shows the “Max. Width × predetermined length correspondence process” subroutine of (S-08).
The supply amount of foam corresponding to “Max.width × paper length” is called from the table (S-101), and the supply of the foam amount necessary for the paper size is performed by the high-pressure air supply unit 221 serving as the supply means ( S-102).
The partition wall width is set to Max. The motor 275 is driven until the width is reached (S-103), and the operation of applying the processing agent to the paper is executed (S-104).
FIG. 13 shows the “size A handling process” subroutine of (S-09).
The amount of foam corresponding to “width of size A × length” is called from the table (S-111), and the amount of foam necessary for the paper size is supplied by the high-pressure air supply unit 221 serving as a supply means. (S-112).
The motor 275 is driven until the partition wall width becomes the width size of the paper size A (S-113), and the operation of applying the processing agent to the paper is executed (S-114).

FIG. 14 shows the “size N width corresponding process” subroutine of (S-10).
The amount of foam corresponding to “width of size N × length” is called from the table (S-121), and the amount of foam necessary for the paper size is supplied by the high-pressure air supply unit 221 serving as the supply means. (S-122).
The motor 275 is driven until the partition wall width becomes the paper size N (S-123), and the operation of applying the processing agent to the paper is executed (S-124).
FIG. 15 shows the “Min. Width × predetermined length correspondence process” subroutine of (S-11).
The amount of foam supplied corresponding to “Min.width × predetermined paper length” is called from the table (S-131), and the amount of foam necessary for the paper size is supplied by the high-pressure air supply unit 221 serving as a supply means. (S-132).
The partition wall width is set to Max. The motor 275 is driven until the width is reached (S-133), and the operation of applying the processing agent to the paper is executed (S-134).

Next, a series of processing operation examples of the processing agent application control corresponding to the application area information in response to the print command in this image forming apparatus will be described with reference to the flowchart shown in FIG. In this flowchart, processing according to application area width information is described.
In the conditional branch (S-51) with or without printing command, if N, return to the original, if Y, A3 width (297 mm) indicating the distance between the front partition 270a and the rear partition 271a as the maximum width (for example, FIG. 2) )) Is started up by starting the motor 275 (S-52).
When the HP sensor 276 detects the outer wall surface of the rear partition wall 271a, it is recognized as HP (S-53).
By obtaining this signal, it can be set by commanding the number of rotations of the motor 275 up to an arbitrary width dimension (in the case of a stepping motor), so that the initialization of the width drive control is executed. Become.

Next, area width information for applying the processing agent is acquired based on a print command or input information from the operation unit by the operator, thereby acquiring width x length information of the application area (S-55).
Supply of the required amount of foam to the application area is performed by the high-pressure air supply unit 221 serving as a supply means (S-56).
The motor 275 is driven until the partition wall width becomes the region width dimension (S-57), and the operation of applying the processing agent to the sheet is executed (S-58).
Next, a conditional branch is made depending on the presence or absence of a print instruction for the next page (S-59). If Y, the process loops to (S-52). If N, the main flow ends.

Next, an outline of the control unit of the image forming apparatus will be described with reference to a block diagram shown in FIG.
This control unit is used as a working area and a CPU 801 that performs system control of the image forming apparatus, a ROM 802 that stores information such as a program executed by the CPU 801, and particularly an FF (feed forward) control table of the present invention. RAM 803, an operation display unit 804 for performing various settings by the operator, various sensors 805 for detecting paper size, jam detection, etc., various motors 806, various sensors 805, various motors 806, etc. I / O control for an I / O 807 for performing a signal, a reading control unit 809 for controlling an image reading device (scanner unit) 808, a printing control unit 811 for controlling a plotter unit (printing mechanism unit) 810, and a telephone line Including the control of the network control device 812 that performs the communication control unit 8 that performs various facsimile communication controls. 3, and a foam application control unit 814 or the like for controlling the foam application device 200.
Here, the various sensors 805 include temperature / humidity detection means for detecting environmental conditions and liquid end detection means (not shown) for detecting whether or not the processing liquid 201 that can be a foam is in the container 202.

FIG. 18A shows a case where the gap between the partition walls (front partition wall and rear partition wall) and the rollers (coating roller and bubble transport roller) is set to be smaller than the average diameter of the bubbles in the bubble storage unit 237. FIG. 6 is a detailed front view showing the positional relationship among the application roller 232 (or the foam generation application roller 234), the bubble transport roller 233, and the front partition 270a or the rear partition 271a.
Between the partition wall and each roller, a gap size: G narrower than the average diameter (assumed to be φ100 μm) of the foam stored in the foam storage section 237 is provided in the radial direction of each roller.
The cross section is shown in FIG. There is a gap G between the surface of the lower rollers (234, 232, 233) and the partition walls (270a, 271a), and there are bubbles that are refined by shearing force as the rollers rotate.
In addition, there is a small bubble 210d on the lower right side of the partition wall (in the bubble storage part), and a liquid film of the processing agent liquefied between the bubbles is present on the roller surface at the bottom, the partition wall surface, and the gap part. Due to the surface tension of the treated agent, the region on the left side of the partition wall (outside the foam reservoir) is shielded without causing bubbles or liquefied treatment agent to flow out.

  By making the gap dimension G narrower than the average diameter of the bubbles in this way, not only is the foam in this part (bubble storage part 237) narrower than that, but a strong external force that attempts to actively pass through G: The liquefied treatment agent collected at the bottom also bubbles due to the shearing force with the roller, and the slightly remaining liquefied treatment agent also envelops the fine bubbles due to surface tension. The left side has a shield structure that does not ooze out.

FIG. 19A shows an application roller 232 (or foam generation application roller 234), a foam transport roller 233, a front partition 270a, or a rear partition 271a when there is no gap in the contact portion between the partition and the roller. It is a detailed front view which shows these positional relationships.
FIG. 19B shows a cross-section of the partition walls and the rollers without gaps. There is no gap between the surface of the lower rollers (234, 232, 233) and the partition walls (270a, 271a), and in the illustrated case, the partition wall slightly bites into the rollers. Needless to say, the partition wall and the rollers may be in contact with each other. If it is such arrangement | positioning, the effect | action which prevents a bubble from leaking to the left side of illustration (outside of a foam | bubble storage part) by the contact with rollers of a partition is shown.

It should be noted that, in the gap portion between the partition wall and the roller, and in the contact portion between the partition wall and the roller and the surrounding surface, the water repellency is such that the contact angle when the bubble is in a liquid state is 90 degrees or less. In FIG. 19B, it is shown as a partition structure having a contact portion without a gap.
There is a small bubble 210d on the lower right side of the partition wall, and there is a liquid film of the processing agent liquefied between the bubbles on the roller surface at the bottom and the partition surface, and the partition wall also gets wet by the surface tension of the liquefied processing agent. However, the wall surface is made of “a water-repellent material having a contact angle of 90 degrees or more when the foam is in a liquid state, or a material subjected to water-repellent treatment on the surface”. The treatment agent that has been partially liquefied will not ooze out from the contact part between the partition wall and the rollers because it tries to be repelled without trying to get wet. The shield structure does not come out.

FIG. 20A shows the application roller 232 (or the foam generation application roller 234) indicating that “the contact portion with the roller has no gap and is an elastic body or has a flexible structure”. FIG. 5 is a detailed front view showing a positional relationship between the bubble transport roller 233 and the front partition wall or the rear partition wall 271a.
It is attached to the bottom of the partition wall (270a, 271a) between the partition wall and each roller, and is composed of an elastic body 277, a body part 278a, a support part 278b, and a flexible part 278c so as to follow the roller shape without any gap. The member which has property is arrange | positioned, and it is FIG.20 (b), (c) which shows the cross section.
In FIG. 20 (b), there are concave portions at the lower part of the partition walls (270a, 271a), and elastic bodies 277 having convex portions are fitted from both left and right sides of the figure so as to fit into the shape.
The elastic body 277 may be made of a vulcanized rubber, a molding material such as polyurethane or other elastomer, or an elastomer formed by a two-color molding method with partition walls (270a, 271a).

  As shown by a two-dot chain line in the figure, in a natural state where the rollers ((234), 232, 233) are not in contact, the shape swells downward than when they are in contact. This indicates that the partition wall is bent due to the contact pressure with the rollers ((234), 232, 233) in the state of use, and thereby processing that bubbles or liquefies from the contact portion between the partition wall and the rollers. The agent does not ooze out, and has a shield structure that does not ooze out on the left side of the partition wall (outside the foam reservoir).

On the other hand, in FIG. 20C, instead of the elastic body, a flexible material, for example, a vulcanized rubber or an elastomer, which is not limited thereto, is made of a flexible resin material.
Similar to the above, there are recesses in the lower part of the partition walls (270a, 271a), and a body part 278a having protrusions is fitted from both the left and right sides of the figure so as to fit into the shape, and the support part 278a is provided below the same. There is a flexible portion 278c at the fork, and swings by an external force at the support portion 278a.
As shown by the two-dot chain line, when in a natural state where it is not in contact with the rollers ((234), 232, 233), it has a shape swelled downward than when it is in contact, In the state of use, it shows that it is bent by the contact pressure with the rollers ((234), 232, 233).
As a result, bubbles or liquefied treatment agent does not ooze out from the contact portion between the partition walls and the rollers, and a shield structure is formed that does not ooze out to the left side of the partition walls (outside the foam storage portion).

By providing the flexible portion 278c having a flexible structure, even if the material itself is not viscoelastic, it has a degree of freedom due to the hinge-like flexible portion structure such as the support portion 278a and the flexible portion 278c. Therefore, it can function as long as the material can be used. Therefore, the flexibility of selecting the material can be expanded, and the effect of improving the adaptability of the function, application, cost, manufacturing method, and the like can be expected.
Furthermore, since this structure can be achieved even with a material having a relatively high molecular weight (a material that seems to be hard), the problem of leakage due to a problem due to creep deformation that is likely to occur with a low molecular weight material is avoided. I can also expect that.

FIG. 21 (a) shows that “it is made of an absorbent body having no gap in the contact portion with the roller and having an absorptivity (capillary force) (relative to the liquid when the bubbles are in a liquid state)”. It is a detailed front view which shows the positional relationship of the application | coating roller 232 (or foam production | generation application roller 234), the foam conveyance roller 233, and the front partition 270a or the rear partition 271a which are shown.
An absorber 279 made of a member attached to the bottom of the partition wall (270a, 271a), elastically deforming to follow the roller shape without a gap, and having absorptivity (capillary force) is disposed between the partition wall and each roller. FIG. 21 (b) shows a cross section thereof.
There are recesses in the lower part of the partition walls (270a, 271a), and absorbers 279 having protrusions are fitted from both left and right sides of the figure so as to fit into the shape.
The absorbent body 278 is made of foamed polyurethane or other polymer material foamed into a closed cell or open cell structure, or impregnated with a fixing material so as not to fray a fiber material such as a nonwoven fabric. It may be a material, or a material in which minute pores are formed by molding and molding a granular polymer material by heat or crosslinking.

As shown by the two-dot chain line, when in a natural state where it is not in contact with the rollers ((234), 232, 233), it has a shape swelled downward than when it is in contact, In the state of use, it shows that it is bent by the contact pressure with the rollers ((234), 232, 233).
As a result, bubbles or liquefied treatment agent does not ooze out from the contact portion between the partition walls and the rollers, and a shield structure is formed that does not ooze out to the left side of the partition walls (outside the foam storage portion).

In addition, since a gap is not provided between the surface of the rollers and the partition wall and the absorber 279 is further interposed to contact each other in a state of being pressurized by the restoring force, the foam is stored as the partition wall. And leakage to other ranges can be completely prevented.
Absorbing the surrounding liquefied processing liquid by capillary force and preventing the permeation to the surroundings, the absorber 279 is in contact with the rollers ((234), 232, 233), and further shearing force due to rotation As a result, the treatment liquid that has been liquefied also has the effect of foaming again, and the coating concentration distribution on the paper can be made uniform without causing irregularities such as liquid.

  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 in the example which produces | generates and apply | coats foam from the liquid which can be made into a foam state, this invention produces | generates foam from the gel which can be made into a foam state. The present invention can also be applied to an apparatus for applying to a member to be applied and an image forming apparatus provided with 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, 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 resin fine particles are quickly fixed on a medium after coating and no residual oil feeling is generated on the medium.

  That is, the fixing solution is in the form of bubbles containing bubbles, and the film thickness of the fixing foam layer is controlled in accordance with the applied pressure, so that the toner offset and image flow to the contact application means such as the application roller can be reduced. It is possible to prevent and fix 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.

DESCRIPTION OF SYMBOLS 100 Paper as recording medium 200 Foam application apparatus as foam application means 201 Treatment liquid as liquid 205 First bubble generation unit 206a as bubble generation means 207 Supply port 207 Second bubble generation unit as bubble generation means 208 Application means Foam application part 210 Foam 237 Foam storage part 241 Foam refinement member 250 Extension part 260 Extension part diaphragm member 270a Front partition 271a as partition member 271a Rear partition 277 as partition member Elastic body 279 Absorber 280a First flap 281a second flap 282a third flap

Claims (15)

In an image forming apparatus for forming an image on a recording medium,
A foam application means for applying, as a processing agent or a fixing agent, a foam in which at least one of a liquid and a gel is foamed to a recording medium or an intermediate member to be applied to the recording medium;
The foam applying means includes foam generating means for generating the foam;
Application means for applying the foam to the recording medium or the intermediate member;
A supply width variable means capable of changing a supply width of the bubbles from the foam generating means to the coating means in a direction perpendicular to the recording medium conveyance direction;
An image forming apparatus comprising: In an image forming apparatus for forming an image on a recording medium,
A foam application means for applying, as a processing agent or a fixing agent, a foam in which at least one of a liquid and a gel is foamed to a recording medium or an intermediate member to be applied to the recording medium;
The foam applying means includes foam generating means for generating the foam;
Application means for applying the foam to the recording medium or the intermediate member;
Application width variable means capable of changing the application width of the bubbles from the bubble generation means to the application means in a direction perpendicular to the recording medium conveyance direction;
An image forming apparatus comprising: The image forming apparatus according to claim 1 or 2,
The image forming apparatus according to claim 1, wherein the foam generating unit includes an extending portion that extends the bubbles in the supply width direction or the application width direction when supplying the foam to the application unit. The image forming apparatus according to claim 3.
Within the supply width region, a foam storage part is formed between the extension part and the application means, and the supply width variable means has a pair of partition members that can move the foam storage part in the supply width direction. Then, the supply of the foam from the foam generation means to the foam storage unit is performed from a supply port narrower than the minimum width of the movable range of the pair of partition members. The image forming apparatus according to claim 3.
Within the coating width region, a foam reservoir is formed between the extension portion and the coating means, and the coating width variable means has a pair of partition members that can move the foam reservoir in the coating width direction. Then, the supply of the foam from the foam generation means to the foam storage unit is performed from a supply port narrower than the minimum width of the movable range of the pair of partition members. The image forming apparatus according to claim 4 or 5,
Following the movement of the pair of partition members between the pair of partition members and the supply port, the region in the extended portion corresponds to the supply width or the coating width defined by the pair of partition members. An image forming apparatus comprising an extending portion diaphragm member that changes to an appropriate region. The image forming apparatus according to claim 4,
An image forming apparatus comprising: a sealing unit configured to close a region surrounded by the pair of partition members in the bubble storage unit. The image forming apparatus according to claim 7.
The sealing means is provided so as to face each of the pair of partition members, and can be displaced in the height direction of the partition members by increasing or decreasing bubbles, and when the pair of partition members are set at the minimum width position First and second flaps that intersect so as to overlap in the height direction of the partition member;
A third flap provided on the foam generating means side, displaceable in the height direction of the partition member by increasing or decreasing the foam, and pressing the first and second flaps from above with their own weight. An image forming apparatus. The image forming apparatus according to claim 1,
A recording medium width information acquisition means for acquiring width size information in the supply width direction of the recording medium, or a recording medium application area information acquisition means for acquiring application area size information in the application width direction of the recording medium;
An image forming apparatus, wherein the supply width or the application width is changed based on width size information or application area size information from the recording medium width information acquisition unit or the recording medium application area information acquisition unit. The image forming apparatus according to claim 9.
Calling a command value of the amount of foam supply required according to the width size information or the application area size information and the number of print commands from a control table, and performing feedforward control of the foam supply by the bubble generation means An image forming apparatus. The image forming apparatus according to claim 4,
The image is characterized in that the gap between the partition member and the coating means in the supply width varying means or the coating width varying means is set to a dimension narrower than the average diameter of the bubbles in the foam reservoir. Forming equipment. The image forming apparatus according to claim 4,
An image forming apparatus, wherein there is substantially no gap between the partition member in the supply width varying unit or the coating width varying unit and the coating unit. The image forming apparatus according to claim 11 or 12,
The partition member is made of a water-repellent material having a contact angle of 90 degrees or more when the foam is in a liquid state or a surface-treated material. An image forming apparatus. The image forming apparatus according to claim 4,
There is substantially no gap between the partition member and the coating unit in the supply width varying unit or the coating width varying unit, and the coating unit side of the partition member has a structure having an elastic body or flexibility. An image forming apparatus. The image forming apparatus according to claim 4,
There is substantially no gap between the partition member and the coating means in the supply width variable means or the coating width variable means, and the coating means side of the partition member is in the liquid when the bubbles are in a liquid state. An image forming apparatus comprising an absorber having absorbency or capillary force.

Images