JP2014046290A - Processing liquid coating device and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem caused when foreign materials are mixed into a liquid pool of a processing liquid and the liquid pool is divided to widen a gap between a coating member and a holding member, and thereby a feed rate of the processing liquid becomes unstable.SOLUTION: A processing liquid coating device is configured: to supply a processing liquid 201 from a supply part 205a in a central part having the longest distance from a removal means 210; to generate a flow in an arrow direction toward an end side from the central part in a liquid pool 204; to make foreign materials 220 flow to an end direction by the flow to the arrow direction of the processing liquid; to supply the processing liquid 201 from supply units 205b, 205b after the foreign materials 220 have passed below the supply unit 205b, 205b; and to make the foreign materials 220 flow to the end direction furthermore.

Description

  The present invention relates to a processing liquid coating apparatus and an image forming apparatus, and more particularly to a processing liquid coating apparatus and an image forming apparatus that apply a processing liquid to a recording medium.

  As an image forming apparatus such as a printer, a facsimile, a copying machine, a plotter, or a complex machine of these, for example, a liquid discharge recording type image forming using a recording head composed of a liquid discharge head (droplet discharge head) that discharges ink droplets. As an apparatus, an ink jet recording apparatus or the like is known.

  In such an image forming apparatus, a treatment liquid that is a modifying material for modifying the surface of a recording medium is applied to promote ink fixing.

  A conventional treatment liquid coating apparatus includes an application member for applying a liquid to an application medium and a liquid holding member for holding the liquid in a liquid holding space, and the liquid is obtained by moving the application member relative to the application medium. A device is known that includes a liquid application unit that applies a liquid in a holding space to an application medium via an application member, and a control unit that controls the amount of liquid applied by the liquid application unit (Patent Document 1). .

WO07 / 020899

  However, in the conventional processing liquid coating apparatus, the number of sheets passing through the liquid pool in the processing liquid holding space formed between the coating roller that applies the processing liquid to the recording medium and the liquid holding member. As the value increases, foreign matters such as paper dust may enter the liquid supply unit.

  In this way, when foreign matter is mixed in the liquid reservoir, the foreign matter becomes a lump and adheres to the application roller and the liquid holding member, and the liquid reservoir is divided in a direction (roller axial direction) perpendicular to the paper transport direction. It will end up. In addition, the gap between the application roller and the liquid holding member widens due to the lump of foreign matter, the supply amount of the processing liquid to the application roller is unstable, and the film thickness becomes non-uniform so that stable application cannot be performed. There are challenges.

  The present invention has been made in view of the above problems, and an object thereof is to enable stable coating.

In order to solve the above-described problems, a treatment liquid coating apparatus according to the present invention includes:
An application roller for applying a treatment liquid to a recording medium;
A holding roller for holding the treatment liquid with the application roller;
A plurality of supply units for supplying the processing liquid to a processing liquid holding space formed between the application roller and the holding roller;
Removing means for removing the treatment liquid on the coating roller;
Control means for controlling the supply of the treatment liquid from the plurality of supply units,
The control means performs supply control to vary at least one of supply timing and supply amount of the plurality of supply units,
Larger flow of the processing liquid than in the case where the processing liquid pool held in the processing liquid holding space is supplied from the plurality of supply units toward the removing unit at the same supply timing and supply amount. It was set as the structure which produces.

  According to the present invention, stable coating can be performed.

1 is an overall configuration diagram of an example of an image forming apparatus according to the present invention. FIG. 2 is an explanatory plan view of a processing liquid coating device portion of the image forming apparatus. FIG. 2 is a block explanatory diagram illustrating an example of a control unit of the image forming apparatus. It is explanatory drawing with which it uses for description of mixing of the foreign material in a liquid reservoir. It is a plane explanatory drawing similarly. It is explanatory drawing with which it uses for description of simultaneous supply control in the case of providing a some supply part. It is explanatory drawing with which it uses for description of the foreign material removal supply control by the control part in 1st Embodiment of this invention. It is side surface explanatory drawing of the part in connection with the removal and collection | recovery of the process liquid coating device. It is explanatory drawing of the separation state which uses for operation | movement description of a removal means. It is explanatory drawing of the contact state similarly provided for operation | movement description of a removal means. It is a flowchart with which it uses for description of the whole flow of control by a control part.

  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 will be described with reference to FIG. FIG. 1 is an overall configuration diagram of the image forming apparatus.

  The image forming apparatus includes an image forming unit 101 that forms an image on a sheet 1 that is a recording medium, a transport unit 102 that transports the sheet 1 so as to face the image forming unit 101, and a sheet 1. A sheet feeding unit 103 that feeds 1 to the transport unit 102 and a processing liquid that is disposed on the upstream side of the image forming unit 101 and applies a processing liquid to the image forming surface of the sheet 1 fed from the sheet feeding unit 103 The coating apparatus 200 includes a paper discharge unit (not shown) that discharges the paper 1 on which an image is formed. The processing liquid coating apparatus 200 may be disposed on the downstream side of the image forming unit 102 and applies the processing liquid onto the paper 1 on which the image is formed.

  The image forming unit 101 includes a line-type liquid discharge head having a nozzle row in which a plurality of nozzles that discharge droplets are arranged in a length corresponding to the paper width, and yellow (Y), magenta (M), and cyan, respectively. (C) and recording heads 111y, 111m, 111c, and 111k that discharge ink droplets of each color of black (K) (referred to as “recording head 111” when not distinguished) are provided. Note that the recording head can be mounted on the carriage as a serial type image forming apparatus.

  The conveyor belt 123 includes an endless conveyor belt 123 that is wound between the conveyor roller 121 and the tension roller 122. The sheet 1 is held on the conveyor belt 123 by air suction with the suction fan 124 provided here. However, for example, a configuration in which electrostatic adsorption is performed or other known conveying means can be used. . Further, a conveying means using a roller pair can also be used.

  The paper feed unit 103 separates and feeds the paper 1 stored in the paper feed tray 131 one by one by the paper feed roller 132 and the separation pad 133, and is directed toward the processing liquid coating apparatus 200 by the transport roller pair 134. Transport.

  In this image forming apparatus, the processing liquid 201 is applied to the paper 1 fed from the paper supply unit 103 by the processing liquid coating apparatus 200, and the paper 1 coated with the processing liquid by the processing liquid coating apparatus 200 is transferred to the transport unit. It is sent and held on the conveying belt 123 of 102.

  Then, it is transported by the circular movement of the transport belt 123, and droplets of each color are ejected from the recording head 111 of the image forming unit 102 to form an image, and then discharged to a paper discharge unit (not shown).

  Here, the treatment liquid 201 is a modifying material that modifies the surface of the paper 1 by being applied to the surface of the paper 1. For example, the treatment liquid is applied to the paper 1 (not limited to paper as a material) in advance so that the water content of the ink quickly penetrates the paper 1 and thickens the color component. It is a fixing agent (setting agent) that prevents bleeding (feathering, bleeding, etc.) and back-through, and increases productivity (number of images output per unit time) by speeding up drying.

  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 a solution to which a base such as hydroxypropyl cellulose and a talc fine powder are added. Furthermore, fine particles can be contained.

  Next, the treatment liquid coating apparatus 200 will be described with reference to FIG. FIG. 2 is an explanatory plan view of the processing liquid coating apparatus. In FIG. 2, the supply unit is shown in a state rotated 90 degrees in the horizontal direction from the state of FIG. 1 for easy understanding.

  The processing liquid coating apparatus 200 is disposed with a slight gap with respect to the coating roller 202 and a coating roller 202 that is a coating member that applies the processing liquid 201 to the paper 1. And a holding roller (doctor roller) 203 which is a holding member that forms a processing liquid holding space for holding the liquid.

  Above a portion between the application roller 202 and the holding roller 203, a plurality of supply units 205 (in this example, three, but may be two or four or more) for supplying the processing liquid 201 are provided. They are arranged in a direction (axial direction of the application roller 202) perpendicular to the paper transport direction.

  The processing liquid 201 supplied from the supply unit 205 is held in a wedge-shaped processing liquid holding space formed between the application roller 202 and the holding roller 203 to form a liquid pool 204.

  The liquid reservoir 204 is provided with a liquid level detecting means (not shown) for detecting the liquid level in order to prevent overflow due to excessive supply. As the liquid level detection means, for example, a float type that detects position information in which the float position rises as the amount of liquid increases, or a capacitive type that contacts the detection electrode with the liquid In addition, it is possible to use a system that detects a capacitance that changes according to increase or decrease in the amount of liquid.

  Further, side guides 207 and 207 are provided at both ends of the coating roller 202 and the holding roller 203 so that the processing liquid 201 does not overflow from both sides in the roller axial direction. However, by adjusting the amount supplied to the liquid reservoir 204, it is possible to control so as not to overflow without providing a side guide.

  Further, a press roller 209 that faces the application roller 202 and presses the paper 1 against the application roller 202 is disposed.

  Further, the surface of the application roller 202 is contacted to remove the excess processing liquid (excess liquid) and foreign matter on the application roller 202, and the excess liquid and foreign matter scraped by the removal means 210 are collected. And a recovery unit 211.

  Excess liquid and foreign matter collected in the collection unit 211 are sucked through a tube 212 by a waste liquid pump 524 described later and sent to a waste liquid unit (not shown). At this time, by passing through a filter unit (not shown), it is possible to separate the processing liquid and the foreign matter, and send the processing liquid to the supply unit 205 again for reuse.

  The purpose of applying the treatment liquid to the paper is to change the state of the paper surface as described above. Specifically, by using a liquid that is reactive with the ink used in the image forming unit 101 as the processing liquid to be applied, the dot diameter of the formed image is adjusted, or the fixing ratio of the ink to the paper is adjusted. The glossiness of the paper can be adjusted.

  Further, foreign matters such as paper dust and dust adhering to the paper surface adhere to the application roller 202 and are collected when passing through the treatment liquid coating apparatus 200, so that the foreign matter on the paper 1 is removed. There are also positive effects.

  The image forming unit 101 can apply various printing processes such as an ink jet recording method, a stencil printing method, and an offset printing method regardless of the type of printing process. As a recording medium on which the treatment liquid is applied, paper is used as an example. However, the recording medium is not limited to paper, and various media such as a resin sheet and cloth can be applied.

  Next, an example of the control unit of the image forming apparatus will be described with reference to FIG. FIG. 3 is a block diagram of the control unit.

  The control unit also includes a microcomputer including a CPU 501, a ROM 502, a RAM 503, an I / F 504, and the like that also serves as a control unit according to the present invention and controls the entire image forming apparatus.

  Also, the application roller drive control unit 511 that controls the drive of the application roller 202, the press roller drive control unit 512 that controls the drive of the press roller 509, the supply control unit 513 that controls the supply unit 205, and the waste liquid are controlled. A waste liquid control unit 514 and a removal unit drive control unit 515 that drives the removal unit 210 are provided.

  Furthermore, a liquid pool sensor 301 that detects the amount of liquid in the liquid pool 204 and foreign matter, a waste liquid sensor 302 that detects the amount of waste liquid in the recovery unit 211, a temperature sensor 303 that detects ambient temperature, a humidity sensor 304 that detects ambient humidity, and paper Various types of sensors such as a sheet type setting unit 305 for setting one type and a sheet number counting unit 306 for counting the number of sheets to be passed, and an I / O 516 for inputting signals from the setting unit are provided.

  The application roller drive control unit 511 and the press roller drive control unit 512 rotate the application roller 202 by the application roller drive motor 521 and the press roller 209 by the press roller drive motor 522 in accordance with the sheet conveyance speed and timing.

  The supply control unit 513 drives and controls the supply pump 523 based on the detection signal from the liquid pool sensor 301, and controls the supply of the processing liquid 201 from the supply unit 205 to the liquid pool 204.

  Here, the liquid pool sensor 301 includes various sensors such as a sensor that detects the amount of the processing liquid 201 in the liquid pool 204 and a light reflection type sensor that detects the contamination state of the foreign matter in the liquid pool 201 based on the whiteness of the liquid. A generic term for sensors.

  Next, the mixing of foreign matter into the liquid reservoir will be described with reference to FIGS.

  The paper 1 may be transported with foreign matters such as paper dust generated from the paper 1 itself and dust floating inside and outside the apparatus attached thereto. As shown in FIG. 4, these foreign substances 220 may adhere to the application roller 202 and be carried as it is to the liquid reservoir 204 when the paper 1 passes under the application roller 202. The separated foreign matter 220 stays in the liquid pool 204.

  Here, when the foreign matter removal control is not performed, the foreign matter 220 continues to stay in the liquid pool 204, and when partly aggregated as shown in FIG. . As shown in FIG. 5, when the foreign matter lump 221 is formed, the liquid pool 204 is divided without the treatment liquid flowing into the region where the foreign matter lump 221 is located in the roller axis direction, and the holding roller 203 and the coating roller are further divided. The gap of 202 is enlarged, and there is a possibility that the supply amount becomes excessive. For example, the application becomes non-uniform or excessive application occurs.

  Next, simultaneous supply control when a plurality of supply units are provided will be described with reference to FIG. FIG. 6 is an explanatory diagram for explaining the simultaneous supply control.

  Here, as shown in FIG. 6, three supply sections 205 are arranged in the roller axial direction, the supply section 205 at the center in the roller axial direction is set as the supply section 205a, and the two supply sections 205 at both ends in the roller axial direction are connected. Let it be a supply unit 205b.

  As described above, when the paper is continuously passed through the image formation, foreign matter such as paper dust or dust adhered to the surface of the paper 1 is transferred to the application roller 202 in the liquid reservoir 204 and is stored in the liquid reservoir 204. Will stay. The foreign material 220 in the liquid reservoir 204 is gradually pushed out together with the processing liquid 201 in the axial direction of the application roller 202 by supplying the processing liquid 201 and scraped off by the removing means 210.

  Here, when the processing liquid 201 is supplied simultaneously from the three supply units 205a and 205b, the foreign material 220 existing between the supply unit 205a and the supply unit 205b in the liquid reservoir 204 is supplied from the supply unit 205a. The foreign material 220 tends to stay between the supply unit 205a and the supply unit 205b because it is sandwiched between the flow in the direction of the unit 205b and the flow from the supply unit 205b to the supply unit 205a.

  For this reason, when the number of sheets to be passed increases, the foreign matter 220 is gradually aggregated without being removed, and may eventually become a foreign matter lump 221 as shown in FIG.

  Even if the supply unit 205 is not plural and is arranged at one central portion, the foreign matter 220 accumulated at the end of the liquid reservoir 204 is weakly pushed out in the axial direction of the application roller 202. For this reason, the removal may not be in time and may aggregate.

  Next, foreign matter removal supply control by the control unit in the first embodiment of the present invention will be described with reference to FIG. FIG. 7 is an explanatory diagram for explaining the same.

  In the present embodiment, the supply timing of the processing liquid 201 from the supply units 205a and 205b (the supply order of the plurality of supply units 205) is varied according to the distance from the removing unit 210.

  That is, as shown in FIG. 7A, first, the processing liquid 201 is supplied from the central supply unit 205a having the longest distance from the removing unit 210. As a result, a flow in the direction of the arrow is generated in the liquid reservoir 204 from the center toward the end, and the foreign material 220 flows in the direction of the end due to the flow of the processing liquid in the direction of the arrow.

  Thereafter, when a predetermined time elapses and the processing liquid supplied by the supply unit 205a passes under the supply units 205b and 205b together with the foreign material 220 as shown in FIG. 7B, the supply units 205b and 205b Then, the processing liquid 201 is supplied. As a result, the foreign material 220 flows further in the direction toward the end portion, and is easily removed by the removing means 210.

  In this way, the foreign matter removal and supply control is performed to vary the supply timings of the plurality of supply units, and the flow of the treatment liquid that causes the foreign matter to flow toward the removal means in the treatment liquid reservoir held in the treatment liquid holding space. As a result, foreign matter removal by the removing means can be easily performed.

  Therefore, it is possible to prevent the foreign matter from aggregating gradually without being removed, and finally to become a foreign matter lump, and to remove the foreign matter mixed in the liquid reservoir and perform stable coating.

  The supply of the treatment liquid with different supply timings may always be performed when the treatment liquid is supplied. In such a case, the preparation time until the start of application is long due to the standby time of the supply unit 205b. This reduces the efficiency of the coating operation. For this reason, it is preferable to supply the treatment liquid with such a supply timing varied every certain period of time. It is also preferable that the recording operation is performed at a timing when the recording operation is not performed, such as between print jobs.

  Next, the foreign matter removal supply control in the second embodiment of the present invention will be described.

  In the present embodiment, the supply amount of the processing liquid 201 from the central supply unit 205a having the longest distance from the removing unit 210 is supplied to the removing unit 210 while simultaneously supplying the processing liquid 201 from the three supply units 205a and 205b. The supply amount from the supply units 205b and 205b on the end side where the distance from the short side is short is set larger.

  Since the supply amount from the central supply unit 205a is larger than the supply amounts from the supply units 205b at both ends, a flow in the direction of the arrow occurs from the central part to the end side in the liquid reservoir 204, and the foreign material 220 Flows in the direction of the end due to the flow of the treatment liquid in the direction of the arrow.

  Thereby, the foreign material 220 is easily removed by the removing unit 210.

  Further, as in the first and second embodiments described above, when the foreign substance 220 is removed by the removing means 210 by changing the supply timing or supply amount to increase the flow in the end direction, the supplied processing liquid Since the amount of waste liquid increases when 201 is also scraped off by the removing unit 210, it is preferable that the foreign matter removal supply control is performed according to the amount of foreign matter in the liquid reservoir 204.

  That is, in a state where there is little foreign matter mixing in the liquid reservoir 204, the operation is performed by simultaneously supplying the processing liquid from the three supply units 205 in the same amount, and the supply amount and the supply timing including the scraping operation by the removing unit 210 are changed. The amount of waste liquid can be reduced by changing the supply amount and the supply timing from the normal time when the amount of foreign matter increases.

  Therefore, a third embodiment of the present invention will be described.

  In this embodiment, the number of sheets passed by the sheet counting means 306 (the number of printed sheets in this embodiment) is compared with a predetermined threshold value, and foreign matter removal and supply control is performed when the number of sheets exceeds the threshold value. .

  In other words, since there is little foreign matter mixed in when the number of sheets to be passed is small, the supply from a plurality of supply units 205 is performed simultaneously, and the amount of liquid in the liquid pool 204 is optimized based on the information of the liquid level sensor of the liquid pool sensor 301. Maintain the correct amount.

  As the number of sheets passed increases, the amount of foreign matter mixed in increases. In the case of a general copy sheet, if the number of sheets to be passed exceeds 500, foreign matter mainly composed of paper powder stays in the liquid reservoir 204, and white turbidity is recognized with the naked eye.

  Therefore, for example, when 500 sheets is set as a threshold value and the count value of the sheet number counting unit 306 reaches 500 sheets or more, foreign matter removal and supply control is performed to create a flow of processing liquid in the end direction and actively remove foreign matters. To do.

  In this case, the threshold value for the number of sheets to be passed may be a fixed value or may be arbitrarily adjustable by the user.

  Next, a fourth embodiment of the present invention will be described.

  In the present embodiment, foreign matter removal and supply control is performed according to the paper type set by the paper type setting unit 305.

  That is, printing paper can be controlled to some extent by performing surface treatment, and papers with various surface states are in circulation. For example, while there are papers that have a uniform surface state, such as ink-jet exclusive paper and art paper used for offset printing, there are also papers that can be easily peeled off by surface treatment agents, such as re-paper. To do.

  As described above, when various types of paper are used, even when the number of sheets to be passed is the same, the state of occurrence of foreign matters such as paper dust varies greatly depending on the paper to be used.

  Therefore, the supply control is changed based on the paper type information set by the paper type setting means 305. The paper type setting means 305 may be one that detects the surface state of the paper by a detection means such as a sensor (not shown) and automatically sets the information, or information input by a user from an information input means (not shown) such as an operation panel. A method of setting based on this may be used.

  In the case of a sheet on which the surface treatment agent is easily peeled off, it is preferable to start the foreign matter removal and supply control from the start of paper passing and always perform the foreign matter removal and supply control as long as the paper continues to pass.

  For other types of paper, a coefficient for the number of sheets to be passed to start foreign matter removal and supply control is set in advance according to the degree of occurrence of foreign matters such as paper dust, and the threshold value in the third embodiment is multiplied by the coefficient. Foreign matter removal and supply control is performed when the number of sheets passed is reached.

  For example, if the coefficient is set to 3.0 for a paper that has a uniform paper surface, such as art paper, and is expected to generate a small amount of paper dust, the normal paper removal and supply control is performed. When 500 sheets are set as the number of sheets, foreign matter removal and supply control is performed from 1500 sheets or more obtained by multiplying 500 sheets by a coefficient of 3.0.

  On the other hand, in the case of a paper that is expected to have a high paper dust generation rate, such as a sheet of paper, the coefficient is set to 0.8, for example, and foreign matter removal and supply control is similarly performed from 400 sheets. To do.

  Although a coefficient is used here, the threshold value of the third embodiment can be set in advance for each paper type.

  Next, a fifth embodiment of the present invention will be described.

  In the present embodiment, foreign matter removal and supply control is performed according to the ambient temperature detected by the temperature sensor 303.

  That is, since the viscosity of the treatment liquid 201 to be applied has temperature dependency, the viscosity changes depending on the ambient temperature, and the fluidity tends to change accordingly.

  For example, in a high temperature environment, the treatment liquid 201 has a low viscosity and fluidity, so that the supply interval between the supply units 205 for moving the foreign matter is short and the supply amount may be small. On the other hand, in the low temperature environment, the treatment liquid 201 has a high viscosity and fluidity, so that the supply interval between the supply units 205 for moving the foreign matter is long and the supply amount needs to be increased.

  Specifically, in a high temperature environment, the viscosity of the processing liquid 201 is decreased and the fluidity is increased. Therefore, when the processing liquid 201 is supplied from the central supply unit 205a in FIG. Move in the direction of the part. Therefore, the processing liquid 201 can be supplied from the supply units 205b at both ends at an earlier timing than in a normal temperature and low temperature environment.

  Thus, the supply interval between the supply unit 205a and the supply unit 205b is the shortest in a high temperature environment, and then the supply interval is increased in the order of normal temperature and low temperature. For example, in a high temperature environment, supply is performed from the supply unit 205b one second after the supply of the supply unit 205a. In a normal temperature environment, supply is performed from the supply unit 205b after two seconds from the supply of the supply unit 205a. In a low temperature environment, when the temperature is low, the supply is performed from the supply unit 205b after 3 seconds from the supply of the supply unit 205a.

  On the other hand, since the fluidity increases even when the viscosity of the processing liquid 201 is lowered, the foreign matter 220 moves even if the supply amount from the supply units 205a and 205b is small. Therefore, the amount of supply from the supply units 205a and 205b is controlled to be small at high temperatures and increase in order of normal temperature and low temperature.

  For example, in the high temperature environment, the supply amount is 1.0 cc from the supply unit 205a and the supply unit 205b, respectively, in the normal temperature environment, the supply amount is similarly 1.5 cc, and in the low temperature environment, the supply amount is 2.0 cc. Supply with. Note that the supply amounts of the supply unit 205a and the supply unit 205b do not need to be the same, and an appropriate amount of difference may be provided.

  Here, the supply amount is adjusted by the supply interval based on the detection signal of the liquid level detection sensor so as not to overflow from the liquid pool. The adjustment by the supply interval means that if the operation of supplying from the supply unit 205b next to the supply unit 205a is one operation, the interval between the operations is made longer or shorter.

  Note that the temperature-viscosity characteristic information of the processing liquid and the supply control corresponding to the temperature are stored in advance in the ROM 502 as a sequence table, and optimal supply control is performed based on the temperature detected by the temperature sensor 303.

  Next, a sixth embodiment of the present invention will be described.

  In the present embodiment, foreign matter removal supply control is performed according to the atmospheric humidity detected by the humidity sensor 304.

  That is, the scattering state of paper dust, dust, and the like of the paper changes according to the atmospheric humidity. In a low-humidity environment, foreign matters are likely to be scattered, so that they are likely to be mixed into the conveyance path during paper feeding, and fibers are likely to fall off due to contact with a paper feed roller, etc., and the amount of paper dust tends to increase.

  On the other hand, in a high-humidity environment, the amount of moisture in the atmosphere increases, so that paper dust and dust are also absorbed and become difficult to scatter. Therefore, foreign matter tends to decrease.

  As described above, since the amount of foreign matter staying in the liquid reservoir 204 varies depending on the atmospheric humidity, the control unit stores and holds the sequence table stored in the ROM 502 according to the humidity detected by the humidity sensor 304 as in the case of temperature. Based on the above, supply control is performed.

  For example, in the foreign matter removal and supply control based on the detected humidity, a predetermined coefficient is set according to the detected humidity. In this case, the coefficient is set to decrease as the humidity decreases. For example, when the humidity is near 50%, the foreign matter removal and supply control is performed when the number of sheets to be passed is 500 or more, whereas when the humidity is near 15%, the humidity coefficient is 0.8, for example. The foreign matter removal and supply control is performed when the number of printed sheets reaches 400 or more.

  In addition to this condition, a paper type coefficient can be applied, or temperature control can be added. The relationship between the humidity and the humidity coefficient is stored in the RAM 503 and referred to during operation.

  Next, a seventh embodiment of the present invention will be described.

  In the present embodiment, foreign matter removal and supply control is performed according to the foreign matter detection result of the liquid pool sensor 301.

  When the treatment liquid 201 is colorless and transparent, the place where the foreign matter stays is whitened, so that the stay of the foreign matter can be detected by the reflective photosensor. Further, when the treatment liquid 201 is not colorless and transparent, the presence or absence of foreign matter can be directly detected from the difference in flow resistance by measuring the flow resistance at a plurality of locations in the liquid reservoir 204.

  Thus, by providing the detection means for detecting the foreign matter, supply control according to the presence or absence of the foreign matter and its amount can be performed.

  Next, drive control of the removing means in the image forming apparatus will be described with reference to FIGS. FIG. 8 is an explanatory side view of a portion related to the removal and recovery of the treatment liquid coating apparatus, and FIGS. 9 and 10 are explanatory views for explaining the operation of the removing means.

  The removing unit 210 is a plate-like member that comes into contact with both ends of the coating roller 202 and removes foreign substances and processing liquid.

  By removing the processing liquid at the end of the application roller 202 by the removing means 210, the liquid volume can be reduced from both ends of the liquid pool 204, and the liquid volume of the entire liquid pool 204 can be gradually reduced.

  Here, the removing unit 210 is attached to a shaft member 231 that is rotatably held by a holding unit (not shown). Then, by rotating the shaft member 231 via the timing belt 234 by the drive motor 233 constituting the removing unit driving unit 525, the removing unit 210 can be brought into contact with or separated from the application roller 202, and at the time of contact Can be adjusted.

  Then, the removal unit drive control unit 515 of the control unit separates the removal unit 210 from the application roller 202 as indicated by the broken line in FIG. 9 and FIG. 8 when the foreign matter removal supply control is not performed.

  That is, if the removing unit 210 is always in contact with the application roller 202, the processing liquid 201 is always scraped off, and the supplied processing liquid is wasted waste liquid regardless of whether or not foreign matter removal supply control is performed. Will be.

  Therefore, when the foreign substance 220 is not mixed in the liquid reservoir 204 and the foreign substance removal and supply control for removing the foreign substance is not performed, the removal by the removing unit 210 is not performed, thereby reducing the waste of the processing liquid. can do.

  When foreign matter stays in the liquid reservoir 204 and needs to be removed, the removing means 210 is brought into contact with the application roller 202 to remove the foreign matter as shown by the solid line positions in FIGS.

  For example, when the processing liquid coating apparatus 200 is left unused for a predetermined period (hour), the processing liquid in the liquid reservoir 204 may be deteriorated (thickened), so regardless of the presence or absence of foreign matter. Alternatively, the removing unit 210 may be brought into contact with the application roller 202 to remove the altered processing liquid at an early stage.

  The recovery unit 211 that collects the processing liquid removed by the removing unit 210 described above is connected to the supply unit 205 via the tube 240. Between the collection unit 211 and the supply unit 205, a replaceable filter unit 241 for removing foreign substances from the collected processing liquid and a pump 242 are provided.

  As a result, the processing liquid and foreign matter collected in the collecting unit 211 are sucked by the pump 242, and at this time, the foreign matter is removed by the filter unit 241, and the processing liquid is sent again to the supply unit 205 and re-supplied. The

  Next, the overall flow of control by the control unit described in each of the above embodiments will be described with reference to the flowchart of FIG.

  First, the removing unit 210 is moved to a home position (HP) that is a separated position.

  And it is discriminate | determined whether the foreign material sensor which detects the accumulation state of a foreign material is provided.

  Here, when a foreign matter sensor is provided, a paper passing operation (in this case, an image forming operation) is performed while the removing unit 210 is in the separated position until the foreign matter is detected by the foreign matter sensor, and the foreign matter is detected by the foreign matter sensor. When this is done, a series of foreign matter removal and supply control for foreign matter removal is performed.

  On the other hand, when no foreign matter sensor is provided, foreign matter removal and supply control is performed according to conditions.

  That is, first, the ambient temperature is detected by the temperature sensor 303, and a temperature sequence table for assuming the flow state of the processing liquid in the liquid pool 204 is read.

  Next, the humidity sensor 304 detects the atmospheric humidity, and reads a humidity sequence table that assumes the scattering state of foreign matter.

  Next, a paper type sequence table assuming a paper dust generation state corresponding to the paper type set by the paper type setting unit 305 is read.

  Then, by combining these temperatures, humidity, and paper types, the number of sheets to be passed for performing the foreign matter removal and supply control is determined. After determining the number of sheets to be passed, a sheet passing operation (here, an image forming operation) is started, and when the number of sheets to be passed determined by the print sheet count unit 306 is reached, foreign matter removal supply control is performed to perform the foreign matter removal operation. To start.

  As described above, the supply timing change and the supply amount change for each supply unit 205 according to the distance from the removal unit 210 are performed by the foreign matter removal supply control.

  In the present application, the “paper” is not limited to paper, but includes OHP, cloth, glass, a substrate, etc., and means a material to which ink droplets or other liquids can be attached. , Recording media, recording paper, recording paper, and the like. In addition, image formation, recording, printing, printing, and printing are all synonymous.

  The “image forming apparatus” means an apparatus that forms an image by discharging liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, etc. “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 causing a droplet to land on the medium). ) Also means.

  The “ink” is not limited to an ink unless otherwise specified, but includes any liquid that can form an image, such as a recording liquid, a fixing processing liquid, or a liquid. Used generically, for example, includes DNA samples, resists, pattern materials, resins, and the like.

  In addition, the “image” is not limited to a planar image, and includes an image given to a three-dimensionally formed image and an image formed by three-dimensionally modeling a solid itself.

  The image forming apparatus according to the present invention can also be applied to, for example, an electrophotographic image forming apparatus. For example, the resin fine particles are quickly fixed to the medium without disturbing fine particles containing resin such as toner on the medium such as paper, and after applying the fixer to the medium to which the resin fine particles are adhered. In addition, 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 using a fixing solution of resin fine particles capable of being applied in a minute amount so as not to cause a residual oil feeling.

1 Recording medium (paper)
DESCRIPTION OF SYMBOLS 101 Image formation part 102 Conveyance part 103 Paper supply part 200 Processing liquid coating apparatus 201 Processing liquid 202 Application roller 203 Holding roller 204 Liquid reservoir 205, 205a, 205b Supply part 209 Press roller 210 Removal means 211 Recovery part

Claims (9)

An application roller for applying a treatment liquid to a recording medium;
A holding roller for holding the treatment liquid with the application roller;
A plurality of supply units for supplying the processing liquid to a processing liquid holding space formed between the application roller and the holding roller;
Removing means for removing the treatment liquid on the coating roller;
Control means for controlling the supply of the treatment liquid from the plurality of supply units,
The control means performs supply control to vary at least one of supply timing and supply amount of the plurality of supply units,
Larger flow of the processing liquid than in the case where the processing liquid pool held in the processing liquid holding space is supplied from the plurality of supply units toward the removing unit at the same supply timing and supply amount. A treatment liquid coating apparatus characterized by producing 2. The processing liquid according to claim 1, wherein when the supply timings of the plurality of supply units are made different, the control unit supplies the processing liquid in order from the supply unit that is far from the removing unit. Coating device. When the control unit varies the supply amounts of the plurality of supply units, the supply amount from the supply unit having a long distance from the removal unit is set to be smaller than the supply amount from the supply unit having a short distance from the removal unit. The treatment liquid coating apparatus according to claim 1, wherein the treatment liquid coating apparatus is increased. The processing liquid application according to claim 1, wherein the control unit performs the supply control according to at least one of the number and type of the recording medium to which the processing liquid is applied. apparatus. The processing liquid coating apparatus according to claim 1, wherein the control unit performs the supply control according to at least one of an atmospheric temperature and an atmospheric humidity. Means for detecting the accumulation state of the foreign matter in the liquid reservoir;
The processing liquid coating apparatus according to claim 1, wherein the control unit performs the supply control according to a detection result of the accumulation state of the foreign matter. The removing means is arranged to be displaceable between a position in contact with the application roller and a position retracted from the application roller.
The processing liquid coating apparatus according to claim 1, wherein when the supply control is performed by the control unit, the removal unit is displaced to a position in contact with the coating roller. Separating the foreign matter by a separating means from the excess processing liquid removed by the removing means, and having a collecting means for collecting only the processing liquid;
The treatment liquid coating apparatus according to claim 1, wherein the treatment liquid separated and collected by the collection means is supplied again.   An image forming apparatus comprising the treatment liquid coating apparatus according to claim 1.

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