JP2004160885A - Laminator and image recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize stable coating in consideration of moisture content of a recording sheet printed by an inkjet printer, when the recording sheet undergoes laminate coating. <P>SOLUTION: A laminator and an image recording apparatus comprise an inkjet image forming means, a resin superposing means for superposing a resin film on the sheet, a fixing means for fixing the sheet and the resin film by pressurizing/heating them, and a drying means which is arranged on the conveyance-direction upstream side of the resin superposing means so as to dry the sheet by pressurizing/heating it; the drying means, the resin superposing means and the fixing means are arranged on the conveyance-direction downstream side of the inkjet image forming means; and the amount of heat, which is applied after the sheet enters the drying means, is changed depending on elapsed time for ejecting the ink to the sheet. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a laminating device for laminating sheets recorded by an ink jet recording device or the like with a transparent resin layer, and an image recording device provided with the laminating device.
[0002]
[Prior art]
2. Description of the Related Art In recent years, an inkjet printer that discharges ink onto a recording sheet to record an image has been widely used in various fields because of its simple structure, small size, and low cost. This ink jet printer is designed to apply ink droplets only to the surface of the recording sheet.Therefore, there is significant deterioration after recording such as outflow of image forming ink due to contact with water and fading due to ultraviolet rays. Was not suitable for storage. Therefore, a laminated film coated with a resin film is closely adhered to the recording sheet surface, and the resin film on the recording surface is cured by a method such as heating and melting the resin film on the laminated film by a fixing unit, transferring the resin film to the recording sheet, and then curing. (Laminate coating) has been put to practical use to form a laminate layer by means of the above method and to enable long-term storage.
[0003]
[Problems to be solved by the invention]
In such an apparatus as described above, the recording sheet is subjected to image formation in the image forming section of the printer apparatus, and then is conveyed to the fixing section to be subjected to lamination coating.
[0004]
In a recording sheet on which an image is recorded, there are portions where the time has elapsed since the ink was ejected and portions where the time has not elapsed. Evaporates, so that there is a difference in the amount of water (water content) that constitutes most of the ink depending on the size of the elapsed time after the ink is applied.
[0005]
Since this moisture removes heat from the heating means when performing the laminate coating, a difference in the water content causes a difference in the fixability of the laminate coating. For example, when the fixing condition of the laminate coating is matched to the portion having a low water content, the heat energy is insufficient for the portion having a high water content, so that the fixing failure tends to occur, and the fixing of the laminate coating to the portion having a high water content. If the conditions are met, thermal energy will be excessive for the part with low water content, and reverse transfer (resin film that should have been fixed to the recording sheet in a very short time will be melted again due to excessive thermal energy) (The phenomenon of returning to the base material of the laminate film).
[0006]
After the recording sheet has been subjected to image formation in the image forming section, if the leading end of the recording sheet always enters the fixing section at the same conveying speed and is laminated and coated, any portion of the recording sheet after ink ejection After a lapse of the same time, the sheet enters the fixing section, and the difference in fixing property can be almost ignored.
[0007]
However, after an image is formed on a recording sheet, the leading end of the device having a switchback transport system in which the leading end does not enter the fixing unit but retreats to another part in the apparatus, and the trailing end enters the fixing unit first. In this case, there is a problem that a portion of the recording sheet, where the time has not passed since the ink is applied, enters the fixing portion first, and the above-described problem of the difference in fixing property is greatly affected.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, a typical configuration of a laminating apparatus and an image recording apparatus according to the present invention includes an inkjet image forming unit, a resin superimposing unit for superimposing a resin film on a recording sheet on which an image is recorded, and the recording method. Fixing means for fixing the sheet and the resin film by pressing or heating, and drying means for drying the recording sheet by pressing or heating the recording sheet, which is disposed on the upstream side in the recording sheet conveyance direction of the resin superimposing means. In the laminating apparatus and the image recording apparatus, wherein the drying unit, the resin superimposing unit, and the fixing unit are arranged downstream of the inkjet image forming unit in the recording sheet conveyance direction, after the recording sheet enters the drying unit. The amount of heat applied by the drying unit is changed continuously or discontinuously in accordance with the elapsed time of ink ejection on the recording sheet. It is an butterfly.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
[Example 1]
First Embodiment A laminating apparatus and an image recording apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram of an image recording apparatus according to the present embodiment. In this embodiment, an explanation will be given using an ink jet recording apparatus as the image recording apparatus.
[0010]
The image recording apparatus shown in FIG. 1 has an ink jet recording head 1 as recording means, and records an image by discharging ink on a recording sheet S. The recording sheet S is formed of a long recording sheet, is wound in a roll, is stored in the feeding unit 2, and an image is recorded while being intermittently conveyed by a conveying roller 3 as a recording sheet conveying unit. The recording sheet S on which an image is recorded on the upper surface is cut into a predetermined size by the cutter 4, and is guided by the flap 5 to the switchback path 6 in the direction of arrow A. When the trailing edge of the recording sheet S passes through the flap 5, the flap 5 is rotated to the position shown by the broken line in the figure, and the rotation direction of the reversing roller 7 is reversed. Thus, the recording sheet S is reversed in the conveying direction and conveyed in the direction of arrow B, and is guided to the laminating apparatus 8 with the recording surface facing upward. The cut recording sheet S on the roll side is pulled back until the leading end of the recording sheet S reaches the recording preparation position by the reverse rotation of the rollers in the conveying roller 3 and the feeding unit 2.
[0011]
The laminating device 8 is roughly composed of a drying unit 9, a resin superimposing unit 10, and a fixing unit 11. Hereinafter, each of them will be described.
[0012]
The drying unit 9 nips and conveys the recording sheet S while heating it, and dries it. In the image recording apparatus according to the present embodiment, the recording sheet S on which an image is recorded by the ink jet recording head 1 is coated with a transparent resin film (laminate) by a fixing unit 11 described later, so that the glossiness is excellent and the weather resistance is excellent. A record can be created. However, as described in the background art, the moisture absorbed by the recording sheet S and the moisture or solvent (hereinafter referred to as moisture) contained in the ink cause a problem in lamination. 9 evaporates the moisture and the like of the sheet.
[0013]
The drying means 9 includes a flat plate heater 33 for drying, a platen 34 made of aluminum having a thickness of 2 mm coated with Teflon (R) on a surface which is in direct contact with the recording sheet S, and a drying pressurization made of silicon rubber. And a roller 16. The drying pressure roller 16 is urged against a platen 34 by urging means (not shown) to form a drying nip 35. The drying nip 35 is heated by the flat plate heater 33 and maintained at about 140 ° C.
With the above configuration, since the heat capacity of the platen 34 is small, it is possible to control the drying nip to a desired temperature in a short time after the energization of the flat plate heater 33 is started.
[0014]
The recording sheet S that has passed through the drying nip 35 passes over the fixing and conveying guide 15, and is stacked on the transfer sheet 21 carrying a resin film (laminated material) by the resin superimposing unit 10, and is then conveyed to the fixing unit 11. You.
[0015]
The resin superimposing means 10 has an unwinding roll 19 and a winding roll 20, and has a long transfer sheet 21 wound thereon. The transfer sheet 21 has a resin film (laminated material) formed of a surface material layer and an adhesive layer formed on a base material, and is formed by a guide shaft 17 of the fixing unit 11, a platen roller 23, and a separation shaft 26. Conveyed along. The unwinding roll 19 is configured to be rotatable in a direction in which the transfer sheet 21 is rewound, and to be restricted in rotation with a predetermined torque in a direction in which the transfer sheet 21 is wound up. The take-up roll 20 is configured to be rotatable in the direction of winding up the transfer sheet 21, and to be restricted in rotation with a predetermined torque in the direction in which the transfer sheet 21 is rewound. That is, tension acts on the transfer sheet 21 in both the winding and rewinding directions, thereby preventing wrinkles from occurring. The width of the transfer sheet 21 is slightly wider than that of the recording sheet, so that the entire surface of the recording sheet S can be covered even if the positions in both width directions are slightly shifted.
[0016]
The fixing unit 11 forms a fixing nip 24 by a general thermal head 22, a pressure spring 18, and a platen roller 23. The platen roller 23 is formed of an elastic member whose surface is covered with a silicon-based or fluorine-based coating. In this configuration, when the thermal head 22 applies heat energy to the transfer sheet 21, the adhesive layer of the transfer sheet 21 is softened. Welded.
[0017]
The separation shaft 26 separates only the base material from the transfer sheet 21. The separation shaft 26 is formed with a small curvature (for example, a radius of 5 mm or less), and the recording sheet S and the surface material layer welded to the recording sheet S cannot follow the curvature due to their synthesis and tend to go straight. At this time, the adhesive force at each interface is in the relationship of sheet / adhesive layer> adhesive layer / surface layer >>> surface layer / base material, and peeling occurs between the base material and the surface material layer. Only the take-up roll 20 is taken up by the take-up roll 20 via the separation shaft. On the other hand, the recording sheet S peeled off from the base material advances to the discharge roller 27 integrally with the adhesive layer and the surface layer, and is discharged to the discharge tray 28 outside the apparatus. That is, the adhesive layer and the surface material layer are transferred from the transfer sheet 21 to the recording sheet S, and a protective film for protecting the ink layer on the surface is formed and discharged.
[0018]
The control unit 40 performs overall control of various operation devices such as each roller (motor for driving the same), the inkjet recording head 1, the thermal head 22, the flap 5, and the like.
[0019]
In the apparatus of the present embodiment configured as described above, the first paper edge detection sensor 51 and the second paper edge detection sensor 52 are arranged as shown in the figure. Since the transport speed of the recording sheet S is always constant, when the leading edge and the trailing edge of the recording sheet S pass through the first paper edge detection sensor 51, the control unit 40 determines the paper transport of the recording sheet S based on the passing time. Recognize the length in the direction. The second paper edge detection sensor 51 is arranged at a fixed distance from the drying nip 35, and when detecting the passage of the leading edge of the recording sheet S, the control unit determines that the leading edge of the recording sheet S enters the drying nip 35 for a fixed time. After the lapse of time, the flat plate heater 33 is driven to apply heat energy to the recording sheet S and the transfer sheet 21. At this time, the amount of thermal energy applied to the recording sheet S and the transfer sheet 21 by the flat plate heater 33 is controlled by the control unit 40, for example, to 100% of the capacity of the flat plate heater 33 at the leading end of the recording sheet S, and then the conveyance of the recording sheet S According to the length in the direction, control is performed such that the applied heat energy gradually decreases by 10% every 20 mm. Of course, the above numerical values are merely examples, and it is specified here that all the configurations and controls are included in which the thermal energy applied at the leading end of the recording sheet S is large and the thermal energy applied thereafter is small.
[0020]
Although the present embodiment has been described using a so-called switchback transport system, even in a normal straight transport system, if the transport speed changes during and after ink ejection, the recording sheet S may not be dried. A difference occurs between the elapsed time of ink ejection at the front and rear ends. In this case, the speeds of the conveying roller 3 and the drying / pressing roller 16 are detected by a well-known rotary encoder or the like (not shown) to detect the speed difference and the time difference between the recording sheet S during printing and during drying, and to apply the speed difference accordingly. The application of the present invention is easy by controlling the applied heat energy.
[0021]
With such a configuration and control, the recording sheet on which an image is formed by the ink jet recording head 1 is fixed in a configuration in which the recording sheet enters the laminating apparatus from a portion where a short time has passed since the ink was injected via the switchback transport system. By making the water content of the immediately preceding recording sheet S uniform and realizing constant fixing conditions, stable laminate coating can be achieved.
[0022]
[Example 2]
Next, a second embodiment of the laminating apparatus and the image recording apparatus according to the present invention will be described with reference to the drawings. FIG. 2 is a configuration diagram of the laminating apparatus according to the present embodiment. The same reference numerals are given to the same portions as those in the first embodiment, and the description will be omitted.
[0023]
In the first embodiment, the heat energy applied to the recording sheet S and the transfer sheet 21 is changed by controlling the driving of the flat plate heater 33. However, the present invention is not limited to this. The applied thermal energy can also be changed by changing the pressure at which the flat plate heater 33 is brought into close contact with the recording sheet S and the transfer sheet 21.
[0024]
As shown in FIG. 2, the pressurization of the flat plate heater 33 is performed by a heater pressurizing spring 55, and a cam plate 53 is provided at one end thereof, and a variable pressurizing cam 54 is provided above the cam plate 53 by a motor or the like. It is rotatably provided by a driving means (not shown). By rotating the variable pressure cam 54, the length of the heater pressure spring 55 can be changed, and the thermal energy applied to the recording sheet S and the transfer sheet 21 can be changed by changing the load on the flat heater 33. The timing control is the same as in the first embodiment. For example, 100% of the load generated by the pressure spring at the leading end of the recording sheet S, and then the load generated by 10% every 20 mm in accordance with the length of the recording sheet S in the transport direction. Is controlled by the control unit 40 so that the water content of the recording sheet S immediately before fixing is uniform, and the fixing condition is stabilized by realizing a constant fixing condition. Enables a laminated coating.
[0025]
Other parts are the same as in the first embodiment.
[0026]
【The invention's effect】
As described above, in the laminating apparatus and the image recording apparatus according to the present invention, the inkjet image forming means, the resin superimposing means for superimposing a resin film on a recording sheet on which an image is recorded, and the recording sheet and the resin film Fixing means for fixing by pressing or heating, and drying means disposed upstream of the resin superimposing means in the recording sheet transport direction, for drying the recording sheet by pressing or heating, wherein the drying means and In a laminating apparatus and an image recording apparatus, wherein the resin superimposing means and the fixing means are disposed downstream of the inkjet image forming means in the recording sheet transport direction, the amount of heat applied by the drying means after the recording sheet enters the drying means, Characterized in that the recording sheet is continuously or discontinuously changed in accordance with the elapsed time of ink ejection on the recording sheet. Thus, even when there is a difference in the water content due to a shift in the ink ejection time on the recording sheet, the water content can be made uniform, and the heat energy to be applied in the fixing unit can be stabilized to perform stable laminate coating. it can.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an image recording apparatus according to a first embodiment.
FIG. 2 is an overall configuration diagram of an image recording apparatus according to a second embodiment.
[Explanation of symbols]
S Recording sheet 1 Ink jet recording head 2 Feeding unit 3 Conveying roller 4 Cutter 5 Flap 6 Switchback path 7 Reversing roller 8 Laminating device 9 Drying means 10 Resin superimposing means 11 Fixing means 16 Drying pressure roller 17 Guide shaft 18 Pressure spring 19 unwinding roll 20 take-up roll 21 transfer sheet 22 thermal head 23 platen roller 24 fixing nip 26 separation shaft 27 discharge roller 28 discharge tray 33 plate heater 34 platen 35 drying nip 40 control unit 51 first sheet edge detection sensor 52 second Paper edge detection sensor 53 Cam plate 54 Variable pressure cam 55 Heater pressure spring

Claims (3)

Inkjet image forming means, resin superimposing means for superimposing a resin film on a recording sheet on which an image is recorded, fixing means for fixing the recording sheet and the resin film by pressing or heating, and recording of the resin superimposing means A drying unit disposed on the upstream side in the sheet conveying direction and drying the recording sheet by pressing or heating the drying unit, wherein the drying unit, the resin overlapping unit, and the fixing unit are located downstream of the inkjet image forming unit in the recording sheet conveying direction. In the laminating device and the image recording device arranged on the side,
A laminating apparatus and an image recording apparatus, wherein the amount of heat applied by the drying unit after the recording sheet enters the drying unit is changed continuously or discontinuously in accordance with the elapsed time of ink ejection to the recording sheet. . In paragraph 1,
A laminating apparatus and an image recording apparatus, wherein the heating device in the drying unit is a heater for converting an electric signal into heat, and the heating is changed by controlling the electric drive. In paragraphs 1 and 2,
A laminating apparatus and an image recording apparatus, wherein the pressing device in the drying unit is an elastic member, and changes its physical shape to vary its load.

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