JP6299402B2 - Treatment liquid application equipment - Google Patents

Description

  The present invention relates to a processing liquid coating apparatus having a coating mechanism in which a processing liquid is applied to the front and back surfaces of a recording medium before printing for image formation, and a pressure roller having grooves formed on the surface is held by rollers. About.

  Conventionally, in an image forming system, when printing is performed on a recording medium such as uncoated paper such as high-quality paper or rough paper by an inkjet method, the ink penetrates the recording medium and feathering, bleeding, etc. occur. Immediately before the ink droplets adhere to the medium, a processing liquid capable of controlling the permeability and condensability of the ink is applied by a processing liquid coating apparatus (also referred to as a pre-coating apparatus) provided in the pre-printing stage.

  In this processing liquid coating apparatus, a roll coater system using a rubber roller is applied to the coating mechanism in order to apply the processing liquid to a recording medium such as paper. The roll coater method in the coating mechanism is to nip the recording medium between the coating roller and the pressure roller, but when handling a narrow recording medium, the coating roller and the pressure roller are used in a portion where the recording medium does not exist. Directly nips and the processing liquid accumulates at the nip point, so that a groove is formed on the surface of the pressure roller to suppress the accumulation of the processing liquid. In addition, by holding the pressure roller with a roller, it is possible to suppress the deflection of the pressure roller without increasing the diameter of the pressure roller, and to reduce the size of the apparatus while making the axial load uniform.

  As a well-known technique related to a processing liquid coating apparatus having a coating mechanism having a structure in which a pressure roller having grooves formed on its surface is held by rollers, a “developing apparatus for a diazo type wet copying machine” (Patent Document 1). Reference).

  In the technique according to Patent Document 1 described above, in a diazo type wet copying machine, a developer roller is transferred from the developing roller to the photosensitive surface of the photosensitive paper, and the pressure roller is pressed against the developing roller which has been polished and smoothed. Is a metal roller having a spiral groove with a pitch of 0.5 mm and a depth of 0.1 mm, so that a contact pressure without unevenness is applied to each part of the photosensitive paper.

  However, if the groove is formed on the surface of the pressure roller in this way, there is no recording medium such as paper, so there is a gap at the valley of the groove at the portion where the pressure roller and the application roller directly nip, Although it is possible to effectively prevent the processing liquid supplied from the application roller from collecting at the nip point with the application roller and scattering when the rollers (application roller and pressure roller) after application stop, Assuming that the image forming system is applied to a processing liquid coating apparatus, the nip load of the roller is changed so that the coating amount of the processing liquid can be adjusted according to the resolution of the image. The roller to be held nips strongly, and at this time, the roller is in point contact with the crest portion of the groove and the load is concentrated.

  The present invention has been made to solve such problems, and the technical problem thereof is that it is possible to prevent the treatment liquid from being accumulated and scattered between the pressure roller and the coating roller of the coating mechanism, and the pressure roller An object of the present invention is to provide a treatment liquid coating apparatus capable of suppressing the wear of a roller to be held and extending the life of the roller.

  In order to solve the above technical problem, the present invention applies a treatment liquid to the front surface and the back surface of a recording medium before printing for image formation, and forms a groove on the surface of the pressure roller so that the pressure roller is aligned. In the treatment liquid coating apparatus having a coating mechanism having a structure held in the above, the groove is a spiral groove formed so as to avoid a portion where the roller contacts on the surface of the pressure roller, and the peak of the spiral groove is formed by the roller. It is characterized in that it is flush with a flat portion formed so as to avoid the contact portion.

  According to the treatment liquid coating apparatus of the present invention, the above configuration can prevent the treatment liquid from being accumulated and scattered between the pressure roller and the coating roller of the coating mechanism, and can suppress wear of the rollers holding the pressure roller. Rollers can have a long life.

1 is a block diagram illustrating a schematic configuration of an image forming system including a processing liquid coating apparatus according to an embodiment of the present invention. It is the schematic which showed the detailed structure of the process liquid coating device with which the image forming system shown in FIG. 1 is equipped. It is a figure for demonstrating the effect | action of the process liquid supply unit and process liquid application unit which comprise the application | coating mechanism with which the process liquid application apparatus shown in FIG. 2 is equipped, (a) is the figure which showed schematic structure, (b). FIG. 3 is a perspective view showing an essential part extracted. FIG. 3B illustrates the nip state between the application roller and the pressure roller when the processing liquid is applied to the narrow recording medium in the main part of the application mechanism shown in FIG. FIG. 5B is a diagram from the top surface showing the positional relationship between the roller and the recording medium, and FIG. 5B is a diagram from the side surface showing how the recording medium is conveyed between the application roller and the pressure roller. It is the figure from the side surface direction of the principal part of the application | coating mechanism which showed the flow of the process liquid in the area | region A shown in Fig.4 (a), and the mode of accumulation. FIG. 4 is a partially enlarged schematic view for explaining a detailed configuration according to a well-known technique of a spiral groove provided on the surface of the pressure roller at a main part of the coating mechanism shown in FIG. It is the schematic for demonstrating the process range of the spiral groove given to the surface of the pressure roller of the principal part of the application | coating mechanism shown in FIG.3 (b), (a) is a spiral groove on the whole surface of a pressure roller. The figure regarding the form of the well-known technique given, (b) is a figure regarding the form of the Example which avoided the part which the roller of the surface of a pressure roller contacts, and gave the spiral groove. A part of the state before the roller is worn by the spiral groove formed on the entire surface of the pressure roller in the main part of the coating mechanism shown in FIG. It is the shown schematic. 3B is a partially enlarged view after the roller is worn by the spiral groove formed on the entire surface of the pressure roller in the main part of the coating mechanism shown in FIG. It is the shown schematic. FIG. 8 is a partially enlarged schematic view for explaining the detailed defining requirements in the groove processing of the spiral groove when the main part of the coating mechanism shown in FIG. 3B is configured as shown in FIG. 7B. .

  Hereinafter, examples of the treatment liquid coating apparatus of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a schematic configuration of an image forming system 200 including a processing liquid coating apparatus 220 according to an embodiment of the present invention.

  Referring to FIG. 1, the image forming system 200 includes a paper feeding device 210, a treatment liquid coating device 220, a first ink jet printer 230, a reversing device 240, a second ink jet printer 250, a post-drying device 260, a winding device. A device 270 is provided.

  In this image forming system 200, the recording medium 10 made of, for example, long continuous paper fed out from the paper feeding device 210 is first sent to the processing liquid coating device 220 provided downstream of the conveyance path of the recording medium 10. In addition to the role of suppressing bleeding and show-through of inkjet ink printed on the front surface, back surface, or both surfaces of the recording medium 10 by the processing liquid coating apparatus 220, various processing liquids for improving image quality, such as penetration assistance A coating process for coating is performed. Next, when the recording medium 10 coated by the treatment liquid coating apparatus 220 is sent to the first ink jet printer 230, the first ink jet printer 230 discharges ink droplets to the surface side of the recording medium 10 to obtain a desired value. An image is formed, and then the recording medium 10 is fed into the reversing device 240. In the reversing device 240, the front surface and the back surface of the recording medium 10 are reversed and sent to the second ink jet printer 250. In the second inkjet printer 250, after forming a desired image by ejecting ink droplets on the back side of the recording medium 10, the recording medium 10 is sent to the post-drying device 260, and the post-drying device 260 applied the treatment liquid. After the recording medium 10 is dried, the recording medium 10 is delivered to the winding device 270, and the winding device 270 winds up the recording medium 10. In this way, the recording medium 10 is wound by post-processing after printing on both sides by image formation.

  FIG. 2 is a schematic diagram showing a detailed configuration of the processing liquid coating apparatus 220 provided in the image forming system.

  Referring to FIG. 2, the processing liquid coating apparatus 220 includes an air loop unit 320, a processing liquid coating unit 330, a processing liquid supply unit 340, a processing liquid drying unit 350, and a dancer unit 380.

  Among these, the air loop unit 320 includes a guide roller 321 that is rotatably supported, a feed-in roller 322 that elastically holds the recording medium 10 and rotationally drives it, and a feed-in nip roller 323. In the air loop unit 320, the recording medium 10 conveyed from the paper feeding device 210 via the guide roller 321 is drawn into the air loop unit 320. At this time, in the air loop unit 320, the recording medium 10 fed from the feed-in roller 322 and the feed-in nip roller 323 is slightly loosened to form an air loop AL. The amount of slack in the air loop AL is detected and monitored by an optical sensor, and the motor of the feed-in roller 322 is controlled by a controller that schematically illustrates the amount of slack so that the amount of slack is constant, and the rotation of the feed-in roller 322 is controlled. .

  The recording medium 10 that has passed through the air loop AL passes between the pass shaft 324 and the edge guide 325. Two pass shafts 324 are arranged in a direction perpendicular to the conveyance direction of the recording medium 10, and the recording medium 10 It passes between the pass shafts 324 in an S shape. A pair of edge guides 325 are supported on these pass shafts 324, and the travel position in the width direction of the recording medium W is restricted by setting the distance between the edge guides 325 to be the same as the width dimension of the recording medium 10. And stable running is possible. The edge guide 325 is fixed to the pass shaft 324 by a fixing means such as a screw, and the position can be adjusted according to the width of the recording medium 10 to be used.

  The recording medium 10 that has passed between the pass shaft 324 and the edge guide 325 is given a tension for stabilizing the conveyance by a tension shaft that is in a fixed state, and is delivered to the processing liquid coating unit 330. The processing liquid coating unit 330 includes a rotation-driven infeed roller 331, a feed nip roller 332, a backside coating unit 333, a front surface coating unit 334, a rotationally driven outfeed roller 335, and the recording medium 10 between the outfeed roller 335. A feed nip roller 336 that elastically holds the roller.

  The recording medium 10 conveyed by the infeed roller 331 and the feed nip roller 332 has a processing liquid on one side of the backside application unit 333 including a squeeze roller 337, an application roller 338, and a pressure roller 339. Applied. The recording medium 10 that has passed through the back surface coating unit 33 is coated with a processing liquid on the surface side, which is the other surface, by a surface coating unit 334 including a squeeze roller 347, a coating roller 348, and a pressure roller 349. The recording medium 10 that has passed through the surface coating unit 334 is conveyed to the processing liquid drying unit 350 by the outfeed roller 335 and the feed nip roller 336. Incidentally, the back coating unit 333 and the surface coating unit 334 are both selectively operated, and the processing liquid is applied to either the front surface or the back surface or both surfaces of the recording medium 10. The processing liquid supply unit 340 stores the processing liquid and supplies the processing liquid to the back surface coating unit 333 and the front surface coating unit 334 as needed.

  The treatment liquid drying unit 350 includes a first stage heating roller set 40 including a first stage back surface heating roller 40a and a first stage surface heating roller 40b, a second stage back surface heating roller 50a, and a second stage surface heating roller 50b. It has a second-stage heating roller set 50, a third-stage heating roller set 60 including a third-stage rear surface heating roller 60a and a third-stage front surface heating roller 60b, a discharge conveying roller 70, and a controller 80 schematically shown.

  The first-stage heating roller set 40, the second-stage heating roller set 50, and the third-stage heating roller set 60 are arranged side by side from upstream to downstream in the conveyance direction in the conveyance path of the recording medium 10, and each of the heating rollers 40a and 40b. , 50a, 50b, 60a, 60b (hereinafter referred to as 40a-60b in the text) are rotatably supported by bearings at both ends in the longitudinal direction.

  The first stage back surface heating roller 40a and the first stage surface heating roller 40b, the second stage back surface heating roller 50a and the second stage surface heating roller 50b, the third stage back surface heating roller 60a and the third stage surface heating roller 60b are mutually connected. They are spaced apart and arranged in a staggered pattern. For example, a line connecting the respective rotation centers of the first stage back surface heating roller 40a, the second stage back surface heating roller 50a, and the third stage back surface heating roller 60a, and the first stage surface heating roller 40b and the second stage surface heating roller 50b. The third stage surface heating roller 60b is arranged so that the lines connecting the respective rotation centers are parallel to and spaced apart from each other.

  In addition, a feed roller 359 that rotates and a feed nip roller 360 that elastically holds the recording medium 10 between the feed roller 359 and the feed roller 359 are provided outside the processing liquid drying unit 350. The recording medium 10 conveyed outside the processing liquid drying unit 350 is conveyed between the feed roller 359 and the feed nip roller 360 to the dancer unit 380.

  The dancer unit 380 includes a movable frame 384 having two guide rollers 381 and 382 and a weight 383, a movable frame 384 that is movable in the direction of gravity, a position detection unit that schematically illustrates the position of the movable frame 384, and a movable frame 384 that is rotatable. It has two dancer rollers 385, 386 attached. The recording medium 10 is wound around the two guide rollers 381 and 382 and the two dancer rollers 385 and 386 in a W shape.

  The dancer unit 380 controls the rotational drive of the feed roller 359 based on the output of the position detection means that is schematically shown, and adjusts the vertical position of the movable frame 384. Thereby, the buffer amount of the recording medium 10 between the treatment liquid coating apparatus 220 and the first inkjet printer 230 is ensured.

  FIG. 3 is a diagram for explaining the operation of the processing liquid supply unit 340 and the processing liquid coating unit 330 that form the coating mechanism provided in the processing liquid coating apparatus 220 described above, and FIG. The figure shown and the figure (b) are the perspective views which extracted and showed the principal part.

  Referring to FIG. 3A, in this application mechanism, the processing liquid 101 stored in the cartridge 100 belonging to the processing liquid supply unit 340 is electrically driven, for example, like a tubing pump or a diaphragm pump. The liquid is fed by the pump 102 which is a liquid feeding means, and is supplied to the supply pan 105 belonging to the processing liquid coating unit 330 via the tube 103 having the electromagnetic valve 104 interposed therebetween. Here, the electromagnetic valve 104 serves as an opening / closing means for the tube 103 configured to be electrically opened and closed, such as a ball valve.

  The amount of the processing liquid 101 supplied to the supply pan 105 is detected by the liquid level detection sensor 106, and when it becomes below a certain level, the electromagnetic valve 104 is opened, and the processing liquid 101 is sucked up from the cartridge 100 by the pump 102, A desired amount of liquid is supplied. When the desired liquid amount is reached, the electromagnetic valve 104 is closed and the pump 102 is stopped, so that the liquid amount in the supply pan 105 is kept constant. As described above, the electromagnetic valve 104 is opened only when the processing liquid 101 is supplied, and the operation time is short. Therefore, if a normally closed type that closes the valve except when energized is used, power consumption can be suppressed.

  Next, the processing liquid 101 stored in the supply pan 105 is pumped up by the rotation of the squeeze roller 108 driven by the motor 107. If the squeeze roller 108 has a grooved surface such as an anilox roller or wire bar, for example, it will be less affected by the viscosity of the processing liquid 101 and the printing speed at the time of pumping, and the liquid amount can be easily controlled. It becomes. The surplus of the processing liquid 101 pumped up by the squeeze roller 108 is scraped off by the metering blade 109 and conveyed to the nip point with the application roller 110. Examples of the material of the metering blade 109 include a case where a metal such as SUS, plastic, rubber or the like is used. However, a plastic material may be used from the viewpoint of abrasion of the squeeze roller 108, a function of scraping off excess liquid, and life. desirable.

  The processing liquid 101 conveyed to the nip point is applied to the application roller 110 while being uniformly stretched between the application roller 110 and the squeeze roller 108 in the axial direction. The coating roller 110 has a peripheral surface covered with an elastic body such as rubber, and is driven by a motor 107 via a one-way clutch 111. The processing liquid 101 applied to the application roller 110 is transferred to the recording medium 10 by being nipped between the pressure roller 118 and the application roller 110. As shown in FIGS. 3A and 3B, the pressure roller 118 held by the roller 119 has a center of an arm 112 that can swing by being restrained by a spring 113 attached to one end. And is rotatably supported via a bearing, and is driven by the recording medium 10 through a nip. The arm 112 is in contact with the eccentric cam 114, and the pressure roller 118 can be moved away from the application roller 110 by the rotation of the eccentric cam 114. The recording medium 10 conveyed from the sheet feeding device 210 is pulled by a conveyance roller 116 driven by a motor 115 and conveyed along the guide roller 117 to the outside of the coating mechanism.

  FIG. 4 illustrates the nip state between the application roller 110 and the pressure roller 118 when the processing liquid 101 is applied to the narrow recording medium 10 in the main part of the application mechanism shown in FIG. FIG. 4A is a view from the top surface showing the positional relationship between the roller 119 and the pressure roller 118 and the recording medium 10, and FIG. 4B is a diagram showing the recording medium 10 between the application roller 110 and the pressure roller 118. It is the figure from the side surface direction which showed a mode that it was conveyed.

  In the main part of the coating mechanism, referring to FIGS. 4A and 4B, the narrow recording medium 10 is conveyed between the coating roller 110 and the pressure roller 118 as shown in FIG. 4B. When the treatment liquid 101 is applied, the application roller 110 and the pressure roller 118 are directly nipped at a place where the recording medium 10 is not present as shown by the area A in FIG.

  FIG. 5 is a view from the side of the main part of the coating mechanism showing the flow and accumulation of the treatment liquid 101 in the region A shown in FIG.

  Referring to FIG. 5, when the processing liquid 101 is applied by transporting the narrow recording medium 10 between the application roller 110 and the pressure roller 118, the processing liquid 101 is squeezed in the main part of the application mechanism. A state in which the application roller 110 and the pressure roller 118 accumulate at the nip point N where the nip directly nips when being pumped from the application roller 110 to the application roller 110 is described.

  When the processing liquid 101 accumulates at the nip point N in this way, the accumulated processing liquid 101 adheres to the end of the recording medium 10 and becomes excessive, thereby affecting drying properties, paper deformation, and image quality. In addition, there is a concern that the processing liquid 101 accumulated when the application roller 110 and the pressure roller 118 are separated from each other due to application stop may be scattered to each part in the application mechanism and hinder the basic performance. .

Therefore, if a spiral groove having a pitch of 0.2 to 0.6 mm and a depth of 0.05 to 0.15 mm is provided on the pressure roller 118, a space is formed between the pressure roller 118 and the treatment liquid 101. By passing, the problem of accumulation and scattering at the nip point N can be prevented in advance. Here, regarding the relationship between the pitch and the depth of the spiral groove applied to the pressure roller 118, it is desirable that the combination of the pitch and the depth is such that the area of the groove to be formed is 0.3 mm ² or more per 10 mm.

  FIG. 6 is a partially enlarged schematic view for explaining a detailed configuration according to the well-known technique of the spiral groove 118a provided on the surface of the pressure roller 118 in the main part of the coating mechanism described above.

  Referring to FIG. 6, here, the entire surface of the pressure roller 118 is provided with a spiral groove 118 a with a pitch of 0.4 mm and a depth of 0.1 mm, so that a nip point N between the application roller 110 and the pressure roller 118 is obtained. This shows that even when the amount of the processing liquid 101 supplied to the substrate is large, prevention of accumulation and scattering is achieved. Incidentally, the pressure roller 118 provided with the spiral groove 118a as described above can be produced at low cost by a groove on a lathe.

  By the way, the coating mechanism of the processing liquid coating apparatus 220 according to the embodiment is a roll coater system, and various rollers are nipped with a high load in order to apply a small amount of the processing liquid 101 uniformly. In order to eliminate the problem that the roller is bent and the nip pressure between the rollers becomes non-uniform in the axial direction and the application becomes non-uniform, in order to suppress the bending with respect to the pressure roller 118 in the axial direction. The pressure roller 118 is held by two rollers 119 each at four locations. In order to suppress the bending, it is possible to take measures by increasing the roller diameter. However, if the roller diameter is increased, the size of the apparatus increases and the size of the apparatus increases. By providing the holding roller 119, both the prevention of the deflection of the roller and the increase in the size of the apparatus are achieved.

  FIG. 7 is a schematic diagram for explaining the processing range of the spiral groove 118a applied to the surface of the pressure roller 118, which is the main part of the coating mechanism, and FIG. 7 (a) shows the entire surface of the pressure roller 118. FIG. 5B is a diagram relating to the embodiment of the embodiment in which the spiral groove 118a is provided while avoiding the portion where the roller 119 contacts the surface of the pressure roller 118. .

  Referring to FIG. 7A, when the spiral groove 118a is formed on the entire surface of the pressure roller 118, the treatment liquid 101 is accumulated or scattered at the nip point N between the pressure roller 118 and the application roller 110. However, in this case, the roller 119 that suppresses the bending of the pressure roller 118 is shown in the state after the wear shown in FIG. 9 with respect to the state before the wear shown in FIG. In addition, there is a side effect that the spiral groove 118a of the pressure roller 118 is abraded as if it was transferred. This is a phenomenon that occurs when the crest of the spiral groove 118a on the surface of the pressure roller 118 and the surface of the roller 119 that holds it are close to point contact, and the load is concentrated.

  Therefore, referring to FIG. 7 (b), if the spiral groove 118a is formed avoiding the portion where the roller 119 contacts the surface of the pressure roller 118, the portion where the roller 119 contacts becomes a flat portion. 119 and the pressure roller 118 are in line contact, and wear can be suppressed.

  Thus, the spiral groove 118a formed so as to avoid the contact portion with the roller 119 is also formed with a pitch of 0.4 mm and a depth of 0.1 mm, and the width of the other flat portion is set to 90 of the width of the roller 119. % Or more is practically preferable. That is, if the width of the flat portion other than the spiral groove 118 a on the surface of the pressure roller 118 is 90% or more of the width of the roller 119, the roller 119 can sufficiently satisfy the function of holding the pressure roller 118. it can.

  FIG. 10 is a schematic diagram partially enlarged to illustrate the detailed defining requirements in the groove processing of the spiral groove 118a when the main part of the coating mechanism described above is configured as shown in FIG. 7B. .

  Referring to FIG. 10, here, in the form of FIG. 7B, when the groove processing is performed in which the spiral groove 118 a is formed by avoiding the portion where the roller 119 contacts the surface of the pressure roller 118, the spiral is temporarily illustrated as illustrated. When the valley of the groove 118a and the flat portion are on the same plane, the flat portion becomes concave, and the force for niping the recording medium 10 and the coating roller 110 becomes weak at that portion, and the transfer of the processing liquid 101 is poor. Therefore, it is necessary to form the crest of the spiral groove 118a so that it is flush with the flat portion. Further, if the flat portion other than the spiral groove 118a is made to have a dimension of 25 mm or less, the treatment liquid 101 accumulated in the flat portion flows into the spiral groove 118a on both sides thereof, and effectively prevents accumulation and scattering. Is practically preferable.

  In the treatment liquid coating apparatus 220 according to the embodiment described above, the spiral groove 118a formed on the surface of the pressure roller 118 held by the roller 119 in the coating mechanism is applied avoiding the portion where the roller 119 contacts. At the same time, the crest of the spiral groove 118a is flush with the flat portion formed avoiding the portion where the roller 119 contacts, and the roller 119 and the pressure roller 118 are in line contact to suppress wear. it can. For this reason, the treatment liquid 101 can be prevented from being accumulated or scattered between the pressure roller 118 and the coating roller 110 of the coating mechanism, and the wear of the roller 119 holding the pressure roller 118 can be suppressed, thereby extending the life of the roller 119. be able to.

  The processing liquid coating apparatus 220 according to the embodiment described with reference to FIG. 2 and FIGS. 3A and 3B is merely an example, and the details of each component configuration can be changed. The treatment liquid coating apparatus of the present invention is not limited to the form disclosed in the examples.

10 recording medium 40 first stage heating roller set 40a first stage back surface heating roller 40b first stage surface heating roller 50 second stage heating roller set 50a second stage back surface heating roller 50b second stage surface heating roller 60 third stage heating Roller set 60a Third stage back surface heating roller 60b Third stage surface heating roller 70 Transport roller for discharging 100 Cartridge 101 Processing liquid 102 Pump 103 Tube 104 Solenoid valve 105 Supply pan 106 Liquid level detection sensor 107, 115 Motor 108, 337, 347 Squeeze roller 109 Metering blade 110, 338, 348 Application roller 111 One-way clutch 112 Arm 113 Spring 114 Eccentric cam 116 Conveying roller 117, 321, 381, 382 Guide roller 118, 339, 349 Pressure Over La 118a helical groove 119 the roller 200 imaging system 210 sheet feeder 220 treatment liquid application device 220
230 First inkjet printer 240 Inversion device 250 Second inkjet printer 260 Post-drying device 270 Winding device 320 Air loop unit 322 Feed-in roller 323 Feed-in nip roller 324 Pass shaft 325 Edge guide 330 Treatment liquid application unit 331 In-feed roller 332, 336, 360 Feed nip roller 333 Backside coating unit 334 Surface coating unit 335 Outfeed roller 340 Processing liquid supply unit 350 Processing liquid drying unit 359 Feed roller 380 Dancer unit 383 Weight 384 Movable frame 385, 386 Dancer roller

Japanese Patent Publication No.62-27381

Claims (4)

A processing liquid coating apparatus having a coating mechanism in which a processing liquid is applied to the front and back surfaces of a recording medium before printing for image formation, and a groove is formed on the surface of the pressure roller and the pressure roller is held by a roller. In
The groove is a spiral groove formed on the surface of the pressure roller so as to avoid the contact portion of the roller, and the crest of the spiral groove is a flat portion formed so as to avoid the contact portion of the roller. A treatment liquid coating apparatus characterized in that it is on the same plane. The treatment liquid coating apparatus according to claim 1,
The treatment liquid coating apparatus, wherein the spiral groove is formed with a pitch of 0.4 mm and a depth of 0.1 mm. The treatment liquid coating apparatus according to claim 1,
The width of the flat portion is 25 mm or less. The treatment liquid coating apparatus according to claim 1,
The width of the flat portion is 90% or more of the width of the roller.