JP6531809B2 - Pretreatment liquid coating drying apparatus and printing apparatus - Google Patents

Description

The present invention relates to a pretreatment liquid application drying apparatus and a printing apparatus .

  The ink jet image recording method has rapidly become widespread due to advantages such as low noise, low running cost, and easy colorization. However, when recording on media other than special purpose paper, in addition to the initial quality problems such as bleeding, density, color tone and show-through, etc., these problems are related to image fastness such as water resistance and weather resistance. There have been various proposals to be solved.

  As one of the means for solving these problems, there is a method of improving the image quality by applying a pretreatment liquid having a function of causing the ink to coagulate immediately before the ink droplets adhere to a sheet which is a recording medium. When the pretreatment liquid is applied, it is necessary to dry the paper before discharging the ink. At this time, if continuous paper is used as the paper, there is a risk that cockling, which is the waving of the paper, may occur.

  Here, in Patent Document 1, cockling is prevented by causing the seasoning device to blow the dried and heated water after blowing the sheet after the ink is attached during the printing operation.

  However, in the above-mentioned patent documents 1, since it had a plurality of processes, the device became complicated and became large-scaled.

  Therefore, in view of the above circumstances, the present invention has an object to provide a pretreatment liquid application drying device that prevents the occurrence of cockling while suppressing the complication of the device.

  In order to solve the above-mentioned subject, the present invention has the following means.

Transport means for transporting the recording medium;
A coating device for applying a pretreatment liquid to the recording medium transported by the transport means;
A drying device comprising a heating unit for drying the recording medium to which the pretreatment liquid has been applied;
And (b) a bending conveyance path provided at least one of the downstream and the upstream of the conveyance direction of the recording medium of the drying device,
The bending conveyance path is a path along which the recording medium is conveyed while being wound around a plurality of rollers disposed apart from each other,
The plurality of rollers are rollers in which the recording medium is bent in a convex shape and wound around the first surface side, and the recording medium is bent in a convex shape on the second surface side opposite to the first surface. The rollers wound around are arranged alternately ,
In the drying device, two rows of a plurality of heating rollers arranged along a predetermined direction are provided as the heating means,
The pretreatment liquid coating and drying apparatus , wherein the plurality of rollers constituting the bending and conveying path are arranged along the predetermined direction .

  Therefore, in view of the above circumstances, the present invention has an object to provide a pretreatment liquid application drying device that prevents the occurrence of cockling while suppressing the complication of the device.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the whole structure of the printing system containing the pre-processing liquid application drying apparatus which is embodiment of this invention. It is a schematic block diagram of the pretreatment liquid coating device contained in the printing system of FIG. FIG. 3 is a configuration diagram of the vicinity of a feed-in roller for drawing in the recording medium from the paper feeding device inside the pretreatment liquid coating and drying device of FIG. FIG. 3 is a configuration diagram of the vicinity of a pass shaft on which a recording medium having passed through an air loop inside the pretreatment liquid application apparatus of FIG. 2 is positionally corrected and conveyed. It is a figure explaining a recording medium conveyance in the in feed roller part inside the pre-processing agent liquid application | coating apparatus of FIG. It is a schematic block diagram of the heating drying device vicinity which formed the crookedness conveyance way which controls the cockling immediately after heating drying. FIG. 7 is a schematic view of the heating and drying apparatus of FIG. 6 opened to a front side drying unit and a back side drying unit for loading of a recording medium. FIG. 7 is a view of the heating and drying apparatus of FIG. 6 viewed from the conveyance direction of the recording medium, and is a schematic view for explaining how to open and close the heating and drying apparatus. It is an enlarged view of the 1st structural example of the driven roller of a cock ring suppression apparatus. It is an enlarged view of the 2nd example of composition of a driven roller of a cock ring control device. It is an enlarged view of the 3rd example of composition of a driven roller of a cock ring control device. It is a flowchart showing the drying operation timing, the conveyance operation timing, the application operation timing, and the printing operation timing. 5 is a timing chart showing operation timings of respective devices at the time of printing. It is a figure explaining the whole structure about the inkjet printer which is 2nd embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First Embodiment
(Whole composition of inkjet printer)
FIG. 1 illustrates a schematic configuration of a printing system 100 according to the first embodiment. As shown in FIG. 1, the printing system 100 includes a sheet feeding device 110, a pretreatment liquid coating / drying device 120, a first inkjet printer 130, a reversing device 140, a second inkjet printer 150, a post-drying device 160, and a post-processing device 170. Have. The first ink jet printer 130 and the second ink jet printer 150 are recording devices that eject ink to perform printing.

  In FIG. 1, the continuous recording medium 10 made of, for example, a long continuous paper fed out from the paper feeding device 110 is first fed to the pretreatment liquid coating and drying device 120. In the pretreatment liquid coating / drying apparatus 120, one of the front and the back of the recording medium 10 is used as a pretreatment prior to the image recording by the ink jet method on one side or both sides in the next step. Alternatively, a pretreatment liquid such as an inhibitor is applied to both sides. Furthermore, in the pretreatment coating / drying apparatus, the recording medium 10 is conveyed while the heating / drying apparatus 1 and the cockling suppression apparatus 50 of the present invention dry the pretreatment liquid of the recording medium 10.

  Next, the recording medium 10 subjected to the application and drying process of the pretreatment liquid is sent to the first inkjet printer 130, and the head unit 131 discharges ink droplets on the front side of the recording medium 10 to form a desired image. Ru. Thereafter, the front and back of the recording medium 10 is reversed by the reversing device 140 having a partial drying function such as a dryer. Subsequently, the recording medium 10 is sent to the second inkjet printer 150, and the head unit 151 ejects ink droplets on the back side of the recording medium 10 to form a desired image.

  Then, after printing is performed on both sides of the recording medium 10, post-drying with a hot air by the dryer is performed by the post-drying device 160. Thereafter, the sheet is sent to the post-processing device 170 to perform predetermined post-processing and winding.

  Each component of the printing system 100 according to the present embodiment is operatively connected to a control system (not shown), and signals and the like related to the printing operation are input.

  Next, with reference to FIGS. 2 to 5, the pretreatment liquid coating and drying apparatus 120 will be described. FIG. 2 is a schematic block diagram of the pretreatment liquid coating and drying apparatus 120, showing a state at the time of coating, drying and conveyance. FIG. 3 shows a configuration diagram of the vicinity of a feed-in (FI) roller 22 for drawing in the recording medium 10 from the paper feeding device 110 inside the pretreatment liquid coating / drying device 120. As shown in FIG. FIG. 4 shows a configuration of the vicinity of the pass shaft 25 on which the recording medium 10 having passed through the air loop AL inside the pretreatment liquid coating and drying apparatus 120 is positionally corrected and conveyed. FIG. 5 is a view for explaining the conveyance of the recording medium by the in-feed roller portion inside the pre-processing agent liquid application device of FIG. By the configurations shown in FIGS. 3 to 5 and the like, tension is applied to the recording medium 10 which is continuous paper in the pretreatment liquid coating and drying apparatus 120.

  The pretreatment liquid coating / drying apparatus 120 shown in FIG. 2 has a pretreatment liquid coating apparatus 30 for coating the pretreatment liquid onto the recording medium 10. In order to dry the pretreatment liquid of the recording medium 10, a heating and drying unit (heating and drying apparatus) 1 is provided downstream of the pretreatment liquid application device 30 in the recording medium conveyance direction. Furthermore, the pretreatment liquid coating and drying apparatus 120 includes an air loop unit 20, a pretreatment liquid supply unit 40, and a dancer apparatus 80 in addition to the pretreatment liquid coating apparatus 30 and the heating and drying apparatus 1 described above.

  In FIG. 2, bearings (not shown) are provided at the end of the roller, and a large number of rotatable guide rollers 21, 24 and the like are installed in the pretreatment liquid coating and drying apparatus 120. A passage 70 is formed.

  Reference numeral 22 denotes an FI roller which is rotationally driven by a drive source (not shown) such as a motor. As shown in FIG. 3, the FI nip roller 23 is pressed by the tension of a spring 27 as shown in FIG. Is given.

  The recording medium 10 is elastically held between the FI roller 22 and the FI nip roller 23, and the FI roller 22 is rotated by the driving source, and the recording medium 10 is internally provided in the pretreatment liquid application units 33 and 34. The recording medium 10 can be pulled in from the provided sheet feeding device 110.

  The recording medium 10 fed from the FI roller 22 and the FI nip roller 23 is slightly slackened to form an air loop AL, and the amount of slack in the air loop AL is monitored by an optical sensor (not shown), and the amount of slack is determined. The FI roller 22 is driven and controlled so as to be constant.

  As shown in FIG. 4, two recording media 10 passing through the air loop AL are disposed between the pass shaft 25 and the edge guide 26 and in a direction orthogonal to the conveyance direction (arrow direction) of the recording medium 10. It passes through the pass shaft 25 in the shape of S. A pair of edge guides 26 is supported by the pass shaft 25, and the distance between the edge guides 26 is supported to be the same as the width direction of the recording medium 10.

  Therefore, the travel position of the recording medium 10 in the width direction is restricted by the functions of the pass shaft 25 and the edge guide 26, and stable travel is possible. The edge guide 26 is fixed to the pass shaft 25 by, for example, fixing means such as screws, and the position of the edge guide 26 can be adjusted according to the width dimension of the recording medium 10 to be used. The recording medium 10 having passed between the pass shaft 25 and the edge guide 26 is tensioned for traveling stabilization by a tension shaft (not shown) in a fixed state.

  The recording medium 10 which has passed the tension shaft enters the pretreatment liquid application device 30, and passes between the infeed roller 31 and the feed nip roller 32, which are rotationally driven by a drive source (not shown) such as a motor. As shown in FIG. 5, a plurality of feed nip rollers 32 are disposed along the axial direction of the in-feed roller 31, and each feed nip roller 32 is pressed against the in-feed roller 32 by a spring 37.

  The recording medium 10 having passed between the infeed roller 31 and the feed nip roller 32 sequentially passes through the back surface coating unit 33 that applies the pretreatment liquid on the back surface side and the surface coating unit 34 that applies the pretreatment liquid on the surface side. As a result, the pretreatment liquid is applied to both sides.

  The recording medium 10 which has passed through the surface coating device 34 is disposed between the feed nip roller 36 and the out feed roller 35 which is rotationally driven by a drive source (not shown) such as a motor similar to the rollers 31 and 32 shown in FIG. Pass through. Thereafter, the recording medium 10 passes through the inside of the heating and drying apparatus 1 and then passes through the bending conveyance path 52 along the driven roller 51 of the cockling suppressing device 50 which suppresses the cockling particularly in the standby state.

  Then, similarly to the rollers 31 and 32 shown in FIG. 5, it passes between a feed roller 61 and a feed nip roller 60 which are rotationally driven by a drive source such as a motor. Thereafter, the recording medium 10 is wound in a W-shape over the rotatable dancer rollers 85 and 86 and the guide rollers 81 disposed between the dancer rollers 85 and 86.

  The dancer rollers 85 and 86 are rotatably attached to the movable frame 84 through bearings (not shown) provided at roller end portions, respectively, to constitute a dancer unit 87. A weight 83 is attached to the movable frame 84. The dancer unit 87 is movable along the direction of gravity A, and a dancer unit position detection means (not shown) for detecting the position of the dancer unit 87 is provided, according to the output of the position detection means. The drive source of the feed roller 61 is driven and controlled. With this configuration, the position of the dancer unit 87 can be adjusted, and the buffer amount of the recording medium 10 between the devices is secured.

  After the recording medium 10 passes the discharge roller 82, the recording medium 10 is conveyed to the first ink jet printer 130 in the rear stage.

  With such a configuration, in the pretreatment liquid coating and drying apparatus 120, the pretreatment liquid coating apparatus 30 applies, to the recording medium 10, a pretreatment liquid for improving the image quality, such as preventing ink bleeding and assisting penetration. Thereafter, the pretreatment liquid is evaporated in the heating and drying apparatus 1 and cooled by the dancer device 80 which conveys the recording medium 10 in the level difference, and then conveyed to the first ink jet printer 130 in the subsequent stage.

  In FIG. 2, the feed rollers 31, 35, 61 and the like function as a transport unit of the pretreatment coating / drying apparatus 120.

  FIG. 6 is a schematic configuration view of the heating and drying apparatus 1 and the cockling suppressing apparatus (means) 50 of the present invention. The heating and drying apparatus 1 dries the recording medium 10 to which the pretreatment liquid has been applied. The heating and drying apparatus 1 comprises an upper surface drying unit 1A and a lower surface drying unit 1B.

  The upper surface drying unit 1A has surface drying and heating rollers 4b, 5b, 6b for drying the surface 11 of the recording medium 10, and a plurality of surface steam discharge fans 8 for discharging steam and the like. Similar to the upper surface drying unit 1A, the back surface drying unit 1B discharges the plurality of back surface drying heating rollers 4a, 5a and 6a for drying the back surface 12 of the recording medium 10 and the plurality of back surface steam discharges for discharging steam and the like. It has a fan 9.

  The heating rollers 4a to 6b are driven to simplify the apparatus and the control, and include a heater for heating (not shown) and a heat pipe (not shown) for temperature equalization. The surfaces of the heating rollers 4a to 6b are coated with a non-adhesive film such as a fluorocarbon resin, etc. By this coating, the adhesion of the ink etc. to the roller surface is suppressed, and the adhered material on the roller surface It is possible to suppress the decrease in the heat transfer efficiency to the recording medium 10.

  In the heating and drying apparatus 1, basically, only the coated surface (both sides or either surface) is dried on the recording medium 10 to which the pretreatment liquid is applied. That is, since only the surface 11 side is dried at the time of the surface side application, the surface drying and heating rollers 4b, 5b and 6b are heated and the recording medium 10 is dried. At the time of application on the back side, since only the back side 12 is dried, the back side drying and heating rollers 4a, 5a and 6a are heated and the recording medium 10 is dried. Further, in the case of double-sided coating, in order to dry both sides, the front surface drying and heating rollers 4b, 5b and 6b and the back surface drying and heating rollers 4a, 5a and 6a are heated to dry the recording medium 10.

  On the downstream side near the outlet of the heating and drying apparatus 1, a bending conveying path 52 is formed as a cockling suppressing device 50, which is bent in the conveying direction by arranging a plurality of driven rollers 51 in the conveying direction. .

  As apparent from FIG. 6, the outer diameter of the driven roller 51 is smaller than the outer diameter of the heating rollers 4a to 6b, that is, the roller diameter is increased in curvature. This is because the heating rollers 4a to 6b generate wrinkles (thermoplastic deformation) on the recording medium 10 while the printing is stopped, and the large deformation of the wrinkles during printing later causes the head of the subsequent printer to print. May cause the head to clog or damage the head.

  In the present embodiment, the curvature of the outer diameter of the driven roller 51 is larger than the curvature of the outer diameter of the heating rollers 4a to 6b, that is, the outer diameter of the driven roller 51 is smaller than the outer diameter of the heating rollers 4a to 6b. Accordingly, the recording medium 10 is conveyed while being wound around the plurality of large curvature follower rollers 51, and the difference in curvature between the winding due to the heating rollers 4a to 6b and the plurality of small outer diameter follower rollers 51 The recording medium 10 is squeezed, which has an effect of correcting the curl deformation.

  This winding tendency tends to be larger as the thickness of the recording medium 10 is thicker, and the outer diameter of the driven roller 51 is appropriately selected according to the main recording medium 10 in a range smaller than the outer diameter of the heating rollers 4a to 6b. Also good. The cockling suppression device 50 will be described in detail later.

  FIG. 7 shows the drying unit 1 opened up and down, and when loading the recording medium 10, it is only necessary to pass the recording medium 10 in the opened state.

  As shown in FIG. 8, the front surface drying unit 1A and the back surface drying unit 1B are fixed to the respective belts 16 stretched by the pulleys 15 via the arms 13 and 14, and opening and closing of the heating and drying device 1 is this This is done by rotating the pulley 15. A thermistor 2 is fixed to the frames of the drying units 1A and 1B by a holder 3 for temperature control on each of the heating rollers 4a to 6b.

  In the heating and drying apparatus 1, the control device 90 of the pretreatment liquid coating and drying apparatus 120 executes the heating control process, and based on the detection result of the thermistor 2, the heating rollers 4 a to 6 b are not installed The heating amount (temperature) of each illustrated heater (heater lamp etc.) is controlled.

  Here, the set temperatures of the front surface drying first stage heating roller 4b and the back surface drying first stage heating roller 4a are equal to or lower than the setting temperatures of the heating rollers 5a, 5b, 6a and 6b in the subsequent stages, It is set. This is because the first stage heating rollers 4a and 4b are the first heating rollers into which the recording medium 10 enters, and if the first stage is set to a high temperature, the temperature does not rise to the set temperature even during printing. Furthermore, if the temperature does not rise to the set temperature, the power of the heater lamp may remain on even after the conveyance is stopped, and the temperature of the heating rollers 4a and 4b transiently rises after the conveyance is stopped, and the recording medium This is because a large deformation may occur to 10 in some cases.

  Returning to FIG. 6, the cockling suppression device 50 is disposed on the downstream side near the outlet of the heating and drying device 1. In the cockling suppressing device 50, the hollow driven rollers 51 are arranged in the transport direction, whereby a bent transport path 52 which is bent a plurality of times in the transport direction is formed. More specifically, in FIG. 6, in the cockling suppressing device 50 located on the downstream side, the bending conveyance path 52 is formed so as to undulate in the vertical direction (direction orthogonal to the conveyance direction extending in the horizontal direction).

  It is preferable that the distance between the adjacent driven rollers be shorter as the curved conveying path 52 by the plurality of hollow driven rollers 51 is closer to the heating and drying device 1 (D3> D2> D1). For example, with the driven roller 51 on the outlet side of the heating and drying apparatus 1 as a starting point, the inter-axial position of the driven roller 51 on the downstream side is 50, 75, 100, and 100 mm thereafter.

  The reason for shortening the distance between the shafts as the driven roller 51 (right side in FIG. 6) closer to the heating and drying apparatus 1 is that the winding angle of the recording medium 10 becomes larger for a roller with the same outer diameter when the distance between the shafts is short. It is from. When the winding angle of the recording medium is large, the pressure contact area is increased by pressing the recording medium 10 and the driven roller 51, and the free expansion and contraction of the recording medium 10 is suppressed. Furthermore, it prevents uneven temperature and humidity changes in the sheet width direction of the recording medium 10 due to contact, and increases the rigidity of the recording medium 10 in the sheet width direction due to the large winding angle.

  Further, in the cockling device 50 described above, when the driven roller 51 bends the recording medium 10 a plurality of times, the recording medium is compared with the case where the bending occurs once in the positional relationship between the heating device and the device at the subsequent stage. The free deformation in the width direction of the recording medium 10 is particularly suppressed at the portion where the pressure contact is being performed while the deformation is divided by each driven roller 51 without growing the wave deformation (cock ring) at 10. Thus, cockling can be prevented stepwise over a wide range in the transport direction, and even large cockling can be suppressed.

  Therefore, in the recording medium 10, cockling, which is a wave-like deformation in a direction perpendicular to the width (paper width) direction of the recording medium 10 which occurs during standby, and which is parallel to the transport direction is less likely to occur.

  In the present embodiment shown in FIG. 6, the recording medium 10 that has been rapidly dried by the heating and drying device 1 starts to absorb moisture rapidly, particularly immediately after the exit of the heating and drying device 1, and cockling phenomenon tends to be noticeable. In particular, the bending and conveying path 52 is provided on the outlet side of the heating and drying apparatus 1.

  Furthermore, even on the inlet side of the heating and drying device 1, although the degree of deformation is smaller than on the outlet side, cockling may occur because the temperature and humidity change with the heating and drying device 1 is severe. A bending conveyance path similar to the bending conveyance path 52 may be provided. When the cockling suppressing device is provided on the inlet side, the bending conveyance path is formed so as to be corrugated in the direction orthogonal to the inclined conveyance direction. Alternatively, the cockling suppression device 50 may be provided downstream or upstream of the conveyance direction of the recording medium 10 near the drying device 1 or both.

(Configuration example 1 of driven roller)
Here, FIG. 9 shows a cross-sectional view of a first configuration example of the hollow driven roller 51 that constitutes the cockling control device.

  In this configuration, the driven roller 51 has a relatively simple configuration, in which the bearing 54 is fitted into the shaft 58 and the hollow roller 59, the E-ring 57 prevents removal, and the washer 56 and bolt 55 fix it to the frame 53. Do. The inner diameter of the hollow roller 59 is larger than the outer diameter of the shaft 58, and the space between the inner surface of the hollow roller 59 and the outer surface of the shaft 58 is hollow.

  The hollow roller 59 may be made of stainless steel which is resistant to corrosion or aluminum which has a relatively high heat conductivity, and in order to improve the removability, the pretreatment liquid or ink on the roller surface is used similarly to the heating rollers 4a to 6b. A non-tacky film such as a fluorocarbon resin for suppressing adhesion may be applied, but it is not limited to this.

(Configuration example 2 of driven roller)
FIG. 10 shows a cross-sectional view of a second configuration example of the driven roller 51 constituting the cockling control device.

  The driven roller 51 has a hollow hollow roller main body 51A-1 and an end 51B-1 that closes the hollow roller main body 51A-1. The end portion 51B-1 is fixed by fastening to the frame 53 the bearing 54-1 whose axial direction is defined by the sleeve 43 and the E ring 57 in the axial direction by the bearing retainer 42 and the bolt 55. There is.

  The surface layer A2 of the hollow roller main body 51A-1 is covered with a non-adhesive film such as a fluorine resin for suppressing the adhesion of the pretreatment liquid and the ink to the roller surface, similarly to the heating rollers 4a to 6b. The inner layer A1 is made of a heat conductive metal such as aluminum. The hollow roller main body 51A-1 receives heat from the recording medium 10 by passing the heated recording medium 10 while passing around.

  At this time, in order to avoid the influence of temperature, in the hollow roller main body 51A-1, the sheet passing portion is provided by avoiding the portion where the end portion 51B-1 having different thermal conductivity exists. This configuration enables uniform heat transfer from the recording medium 10 to the hollow roller main body 51A-1 in the width direction of the recording medium 10.

  The end 51B-1 for connecting to the frame 53 through the bearing 54-1 is, for example, PI (polyimide), PPS (polyphenylene sulfide), PAI (polyamide-imide), PEI (polyether imide), LCP It is preferable to use a resin material such as (liquid crystal polymer), PEEK (polyether-ether-ketone) resin or ceramic material. The thermal conductivity of the end 51B-1 made of resin is lower than that of the hollow roller main body 51A-1 made of metal, so that the heat insulating effect at the end 51B-1 made of resin is produced.

  Therefore, the amount of heat received by the hollow roller main body 51A-1 can escape to the end 51B-1 as much as possible, and cooling by heat transfer by the driven roller 51 is limited to the volume of the hollow roller main body 51A-1. Therefore, the heat retaining effect of the drying heat is large in this configuration.

(Configuration example 3 of driven roller)
Here, FIG. 11 shows a cross-sectional view of a second configuration example of the driven roller 51 that constitutes the cockling control device. The driven roller 51 has a hollow hollow roller main body 51A-2 and an end 51B-2 having a ventilation passage for passing air. The end portion 51B-2 has an air hole so as to ventilate with the outside, and a bearing 54-2 whose axial direction is defined by the sleeve 43 and the E ring 57 is prevented by the bearing retainer 42 and the bolt 55. , And fixed to the frame 53 by fastening.

  The hollow roller main body 51A-2 has the same structure as that of the structural example 1. The end 51B-2 may be the same material as the hollow roller main body 51A-2 or may be another material, but a material having good thermal conductivity is preferable. The end 51B-2 takes in air from the air hole through the ventilation passage into the hollow roller body 51A-2.

  Therefore, the heat amount received by the hollow roller main body 51A-2 from the recording medium 10 is dissipated to the outside through the end portion 51B-2 and the outside air is taken in, whereby the volume of the hollow roller main body 51A-2 is used using air circulation. The above heat quantity can be received from the recording medium 10 and can be cooled. Therefore, the cooling effect is large in this configuration.

  Also in this configuration, in order to avoid the influence of temperature, in the hollow roller main body 51A-2, the sheet passing portion is provided while avoiding the portion where the end portion 51B-2 is present and the thermal conductivity is different. This configuration enables uniform heat transfer from the recording medium 10 to the hollow roller main body 51A-2 in the width direction of the recording medium 10.

  An electromagnetic valve 44, a pipe 45, etc. are disposed at the end of this configuration and controlled by the controller 46. In particular, when printing a thick recording medium 10, the electromagnetic valve 44 is opened during printing to send in air or cold air. It is also possible to cool the recording medium 10 to prevent the temperature rise of the head portion 131 of the printer 130 at the rear. The electromagnetic valve 44 may be closed before / after printing stop, printing stop, or printing stand-by to reduce temperature change to further suppress cockling.

  Note that since the configuration example 1, the configuration example 2, and the configuration example 3 have different characteristics, the configurations may be appropriately selected and appropriately combined according to the application. As the structure of the driven roller 51, the temperature adjustment function is high in the order of the structural example 3> the structural example 2> the structural example 1 by the exchange of the proportion of hollow and the outside air.

  In the case of using the configuration example 3, for example, warm air is taken and heated so that the temperature between the temperature of the first stage heating roller 4a or 4b and the room temperature is obtained by keeping warm on the upstream side. In order to take in high temperature air for heating, a heat source may be disposed near the temperature hollow roller 51A-2 or heat from the heating and drying apparatus 1 may be drawn. On the other hand, on the downstream side, in order to reduce the difference with the outside air temperature at the time of printing, air and cold air are taken in and cooled.

(Control example of pretreatment liquid application drier)
FIG. 12 is a control flowchart of the pretreatment liquid coating and drying apparatus 120. The operation timing corresponds to the drying operation timing, the application operation timing, the conveyance operation timing, and the printing operation timing indicated by a timing chart described later.

  When printing is started, the pretreatment liquid application drying device 120 receives a print start (PS) signal from the control system as preparation for printing in step (hereinafter simply referred to as S) S101. Then, the temperature rising of the heating and drying apparatus 1 is started, the heater lamps built in the heating rollers 4a to 6b are turned on, and the heating rollers 4a to 6b are heated (S102). The heating rollers 4a to 6b are raised to a desired drying set temperature, and when the start-up is completed (S103), the recording medium 10 is transported in its entirety and the pretreatment liquid application units 33 and 34 start to apply the pretreatment liquid (S104).

  Then, when the recording medium 10 to which the pretreatment liquid has been applied and dried reaches the head portion 131 of the first inkjet printer 130 (S105), the ink is landed from the head portion 131 and printing starts (S106). More specifically, when the recording medium 10 after the application and drying of the pretreatment liquid has reached the first first ink jet printer 130, surface printing such as an image by ink jet is performed. Subsequently, when the recording medium 10 reaches the second ink jet printer 150, the back side printing of an image or the like by ink jet is performed. Thus, the printing operation is continued for a predetermined period.

  When printing is stopped, a printing stop (PE) signal is issued from the control system, and the pretreatment liquid application drying device 120 receives the PE signal and starts operation of printing termination (S107). In this operation, first, application of the pretreatment liquid in the pretreatment liquid application device 30 (33, 34) is ended (S108). Thereafter, the heater lamp is turned off to stop the drying in the heating and drying apparatus 1 to stop the heating of the heating rollers 4a and 6b (S109), and the end of coating ends the recording after exiting the heating and drying apparatus 1 (S110) The conveyance of the medium 10 is stopped (S111).

  By performing such control, the recording medium 10 to which the pretreatment liquid is not applied remains in the heating and drying apparatus 1, and the heating rollers 4a to 6b are not heated, so the deformation of the recording medium 10 is small. It will be in the state. Therefore, the deformation of the recording medium 10 in the heating and drying apparatus 1 is reduced, and the head is broken, the head is damaged, etc. due to the deformation of the recording medium 10 in the head portions 131 and 151 of the recording devices 130 and 150 which are subsequent processes. It has an effect of preventing deterioration of image quality.

  Then, if there is the next JOB (S112), the process returns to the print preparation start again, but if there is not, the process ends.

  The time for the recording medium 10 on which the pretreatment liquid has been applied and dried to reach the head portions 131 and 151 of the recording devices 130 and 150, and the application units 33 and 34 finish application, and the application end exits the heating and drying device 1 outlet. The time up to is calculated by calculating the time from the conveyance distance and the conveyance speed and calculating the time.

  When the temperature of the heating and drying apparatus 1 is raised, the recording medium 10 in the heating and drying apparatus 1 is usually the recording medium 10 to which the pretreatment liquid is not applied. Relatively small. Therefore, in the recording medium 10, the above-mentioned area and the area to which the pretreatment liquid before conveyance stop is not applied are treated as broken sheets as the unprintable area.

  Here, although the case of double-sided printing has been described, single-sided printing of only the front or back is also possible. In this case, the pretreatment liquid is applied and dried on the side to be printed, and the moisture content of the recording medium 10 delivered from the pretreatment liquid application drying device 120 is the value when the paper feeding device 110 delivers it. The water content of the recording medium 10 is made to be substantially equal. This is because when considering a wide variety of recording media, it is sufficient to approach the moisture content of inkjet paper and the moisture content as usual.

  FIG. 13 is a timing chart showing the timings of heating and drying and the application of the pretreatment liquid with respect to the transport timing of the recording medium 10.

  As shown in FIG. 13, after the heating rollers 4a to 6b are raised to the drying set temperature, the drying timing is set such that the pretreatment liquid application ON and the conveyance operation of the recording medium 10 are turned ON to apply and dry. Inkjet printing described later is performed. Then, after stopping the pretreatment liquid application before stopping the entire printing conveyance, the conveyance of the recording medium 10 is stopped after the heating of the heating rollers 4a to 6b is turned off to stop the drying.

  Here, the heating rollers 4a to 6b may be completely turned off as drying OFF, but the standby temperature may be set to about 40 ° C to 45 ° C in order to shorten the temperature rising time in the next printing. If the standby temperature is about 40 ° C. to 45 ° C., the deformation of the recording medium 10 at this temperature is extremely small in consideration of the recording medium to which the pretreatment liquid is not applied.

  By controlling in this manner, the recording medium 10 to which the pretreatment liquid is not applied remains in the heating and drying apparatus 1, and the heating rollers 4a to 6b are not heated, so the deformation of the sheet is reduced. Therefore, the influence of the subsequent sheet deformation in the ink jet head unit 131 on the head unit 131, that is, damage to the ink jet printers 130 and 150 due to head damage and the like is eliminated, and the image quality and quality are not deteriorated, which has an advantageous effect.

  However, during the subsequent printing standby, even if the recording medium 10 is not coated, the recording medium 10 stopped particularly at the outlet side of the heating and drying device 1 has residual heat of the heating rollers 4 a and 6 b of the heating and drying device 1. It has stopped in a sufficiently dry state. Therefore, expansion and contraction of the recording medium 10 tend to occur with rapid moisture absorption, but as described above, cockling is suppressed by the formation of the bending conveyance path.

  As described above, according to the present invention, even if expensive inkjet paper is not used, the pretreatment of coating and drying with the pretreatment liquid is performed, and even if it is on standby, the deformation of the wave shape due to moisture absorption of the recording medium 10 at the outlet of the drying unit You can reduce the number of rings extremely. Therefore, there is no rubbing of the recording medium with the heads 131 and 151 in the post-process by cockling, and there is no pre-treatment liquid coating and drying apparatus without print stains, head stains, print dot chipping due to head clogging, head damage, etc. A recording device can be provided and good printing job can be performed.

Second Embodiment
Here, FIG. 14 shows the printing apparatus of the second embodiment having the heating and drying function and the cockling suppressing function.

  The recording medium heating and drying apparatus 200 according to the present embodiment is an ink drying apparatus, and a printing apparatus 1000 including the apparatus will be described. The schematic block diagram of the whole printing apparatus 1000 which has the heat-drying apparatus 200 in FIG. 14 is shown. In the following, the same components as those of the first embodiment are denoted by the same reference numerals, and points different from the first embodiment will be mainly described.

  As shown in FIG. 14, in the printing apparatus 1000 of the present embodiment, the recording apparatus 400, the paper feeding apparatus 300, and the conveyance unit 500 are disposed upstream of the heating and drying apparatus 200, and downstream of the heating apparatus 200 which is an ink drying apparatus. The post-processing device 600 is disposed. In addition, as the post-processing device 600, a winding device for winding the recording medium 10 after printing or a folding machine can be installed.

  The recording apparatus 400 has a head unit 401 which is an image forming unit, and the head unit 401 A discharges and adheres a liquid such as ink to the recording medium 10 to form an image on the recording medium 10.

  The heating and drying apparatus (heating and drying unit) 200 includes heating rollers 4a, 4b, 5a, 5b, 6a, 6b and exhaust ducts 8, 9 from the upstream of the recording medium 10 in the conveyance direction T, as in the first embodiment. And a discharge roller 7.

  Further, in the heating and drying apparatus 200, a heating control process by the control device 900 is executed to control the heating amount (temperature) of each heater (not shown) of each of the heating rollers 4a to 6b.

  Also in the present embodiment, as in the case of FIG. 6, the bending conveyance path 52 is formed on the downstream side near the outlet of the heating and drying apparatus 1 and bent a plurality of times in the conveyance direction by the plurality of driven rollers 51. It suppresses the cockle-like cockling in the paper width direction that occurs during the process.

  The flow and the like will not be described because they are the same.

  Also in the present embodiment, the pretreatment liquid application drying process is performed without using expensive inkjet paper, and the wave shape deformation and cockling due to the moisture absorption of the recording medium 10 particularly on the exit side of the drying unit are extremely It can be reduced. Therefore, there is no rubbing with the recording medium in the post-processing apparatus 600 in the post-process by the cockling, and good printing work can be performed for the recording medium 10 as well.

1 Heating drying equipment (drying equipment)
4a, 4b, 5a, 5b, 6a, 6b heating roller (heating means)
42 Bearing 43 E ring 44 Solenoid valve 45 Piping 46 Controller 35 Conveying part 50 Cock ring suppressing device (cock ring suppressing means)
51 driven roller 51A-1, 51A-2 hollow roller main body 51B-1, 51B-2 end 52 bent conveying path 53 frame 54, 54-1, 54-2 bearing 58 shaft 59 hollow roller 100 printing system 120 pretreatment liquid Coating / drying apparatus 130 first ink jet printer (recording apparatus)
150 Second inkjet printer (recording device)
1000 printing apparatus 200 heating and drying apparatus 400 recording apparatus

JP 2012-035566 A

Claims (8)

Transport means for transporting the recording medium;
A coating device for applying a pretreatment liquid to the recording medium transported by the transport means;
A drying device comprising a heating unit for drying the recording medium to which the pretreatment liquid has been applied;
And (b) a bending conveyance path provided at least one of the downstream and the upstream of the conveyance direction of the recording medium of the drying device,
The bending conveyance path is a path along which the recording medium is conveyed while being wound around a plurality of rollers disposed apart from each other,
The plurality of rollers are rollers in which the recording medium is bent in a convex shape and wound around the first surface side, and the recording medium is bent in a convex shape on the second surface side opposite to the first surface. The rollers wound around are arranged alternately ,
In the drying device, two rows of a plurality of heating rollers arranged along a predetermined direction are provided as the heating means,
The pretreatment liquid coating and drying apparatus , wherein the plurality of rollers constituting the bending and conveying path are arranged along the predetermined direction . The drying apparatus includes a unit for discharging a vapor to dry the surface of the recording medium,
2. The pretreatment liquid coating and drying apparatus according to claim 1, wherein the bending and conveying path is provided downstream of the conveying direction of the drying apparatus and in the vicinity of an outlet of the drying apparatus.   The pretreatment liquid coating and drying apparatus according to claim 1 or 2, wherein the plurality of rollers are arranged such that central positions of the respective rollers are in the same straight line.   The pretreatment liquid coating and drying apparatus according to any one of claims 1 to 3, wherein an axial distance between the plurality of rollers and an adjacent roller is shorter as the plurality of rollers are closer to the drying device. Transport means for transporting the recording medium;
A recording apparatus that ejects and adheres ink to the recording medium;
A drying device having a heating means for drying the recording medium to which the ink has adhered;
And (b) a bending conveyance path provided at least one of the downstream and the upstream of the conveyance direction of the recording medium of the drying device,
The bending conveyance path is a path along which the recording medium is conveyed while being wound around a plurality of rollers disposed apart from each other,
The plurality of rollers are rollers in which the recording medium is bent in a convex shape and wound around the first surface side, and the recording medium is bent in a convex shape on the second surface side opposite to the first surface. The rollers wound around are arranged alternately ,
In the drying device, two rows of a plurality of heating rollers arranged along a predetermined direction are provided as the heating means,
The printing apparatus according to claim 1, wherein the plurality of rollers forming the bending conveyance path are arranged along the predetermined direction . Transport means for transporting the recording medium;
A recording apparatus that ejects and adheres ink to the recording medium;
A drying device having a heating means for drying the recording medium to which the ink has adhered;
And (b) a bending conveyance path provided at least one of the downstream and the upstream of the conveyance direction of the recording medium of the drying device,
The bending conveyance path is a path along which the recording medium is conveyed while being wound around a plurality of rollers disposed apart from each other,
The plurality of rollers are rollers in which the recording medium is bent in a convex shape and wound around the first surface side, and the recording medium is bent in a convex shape on the second surface side opposite to the first surface. The rollers wound around are arranged alternately,
The drying apparatus includes a unit for discharging the steam to the drying of the surface of the recording medium,
The printing apparatus, wherein the bent conveying path is provided downstream of the drying device in the conveyance direction and in the vicinity of an outlet of the drying device. Transport means for transporting the recording medium;
A recording apparatus that ejects and adheres ink to the recording medium;
A drying device having a heating means for drying the recording medium to which the ink has adhered;
And (b) a bending conveyance path provided at least one of the downstream and the upstream of the conveyance direction of the recording medium of the drying device,
The bending conveyance path is a path along which the recording medium is conveyed while being wound around a plurality of rollers disposed apart from each other,
The plurality of rollers are rollers in which the recording medium is bent in a convex shape and wound around the first surface side, and the recording medium is bent in a convex shape on the second surface side opposite to the first surface. The rollers wound around are arranged alternately,
The printing apparatus according to claim 1, wherein the plurality of rollers are arranged such that central positions of the respective rollers are in the same straight line.   The printing apparatus according to any one of claims 5 to 7, wherein an axial distance between the plurality of rollers and an adjacent roller is shorter as the plurality of rollers are closer to the drying device.

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