JP2006142525A - Coating apparatus for recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating apparatus for a recording medium which can make a temperature distribution in a roller axial direction as uniform as possible at the time of pressurization and heat treatment, and can carry out coating without spots in the axial direction of rollers. <P>SOLUTION: The coating apparatus for the recording medium which forms a coating layer by pressurization and heat treatment is equipped with a recording medium feeding means for feeding the recording medium to a coating sheet, and a coating layer forming means which pinches and pressurizes both the recording medium and the coating sheet and forms the coating layer to a surface of the recording medium. The coating layer forming means consists of the paired rollers of a hollow cylindrical shape. At least one of the rollers is equipped with a roller heating means which extends in the axial direction into the roller and whose heating ability in the axial direction is distribution-adjusted. A heating ability distribution in the axial direction at the roller heating means is set according to a pressurization force applied to the roller. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording medium coating apparatus for forming and protecting a coating layer on the surface of a recording medium on which an image such as a photographic print is recorded.

  The recording methods such as the ink jet recording method and the thermal transfer recording method have been improved on the recording device (printer) and the recording medium (recording paper, etc.), and as a result, an image quality comparable to a silver salt color photograph can be obtained. In recent years, image information captured by a digital camera, image information captured by a scanner, or the like has been widely used as a technique for hard copying. With the expansion of the use of these recording methods, it has become an important issue to improve the water resistance, light resistance, etc. of images recorded by these recording methods, or to improve the beauty of the image recording surface.

  Therefore, as a technique for protecting the image recorded on the recording medium and improving the quality, a technique for protecting the recording surface of the recording medium after the image recording by laminating is known. An example of such a technique is shown below. That is, first, a long recording medium (recording paper) is transported at a constant speed, and a long laminating sheet on which a laminate material can be peeled off is mounted on the mount so as to face the recording surface of the recording medium. Transport the supply. Then, the laminate material is continuously transferred onto the recording surface of the recording medium by applying heat and pressure in a state where the recording medium and the laminate sheet are laminated by the pressure roller pair. Thereafter, only the backing sheet of the laminate sheet is peeled off, and a laminate process is performed on the recording surface of the recording medium. Then, the recording medium subjected to the lamination is sequentially cut by the cutter at the cuts of the image formed on the recording surface, and discharged in a state of being separated for each image (for example, see Patent Document 1).

  In this type of laminating apparatus, pressure is applied between a recording medium and a laminating sheet that is provided with a laminating material that is a covering sheet to form a covering layer on the surface of the recording medium. A mechanism is provided. This pressure mechanism is generally composed of a pair of hollow cylindrical rollers, and is provided with roller heating means such as a heater in the roller, and the roller surface is uniform in the axial method when heated by this heating means. It is comprised so that surface temperature distribution may be comprised.

JP-A-58-224779 (page 1-4, FIG. 1)

However, in this type of heat roller, if a configuration in which the roller surface temperature in the non-pressurized state is uniform in the axial direction is adopted, when the coating layer forming process is actually performed in the pressurized state, the roller axial direction Thus, it has been clarified that a temperature spot is generated in which the central portion becomes low temperature and the roller end portion side becomes high temperature.
When such uneven distribution in the roller axis direction occurs, it has been found that there is a problem that a uniform coating layer cannot be formed in this direction and a good coating layer cannot be obtained.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to constitute a recording medium coating apparatus for forming a coating layer by pressure and heat treatment. The object of the present invention is to provide a recording medium coating apparatus that can make the temperature distribution in the direction as uniform as possible and can perform coating without spots in the roller axis direction.

In order to achieve the above object, the characteristic configuration of the recording medium coating apparatus according to the present invention is as follows.
Recording medium supply means for supplying the recording medium to the covering sheet;
Heating / pressurizing the recording medium and the covering sheet, and a coating layer forming means for forming a coating layer on the surface of the recording medium,
The coating layer forming means includes a pair of rollers, and at least one of the rollers includes a roller heating means that extends in the axial direction thereof, and the heating ability in the axial direction is adjusted.
The heating power distribution in the axial direction of the roller heating means is set according to the pressure applied by the roller.

  In this configuration, it is preferable that the heating power distribution in the axial direction in the roller heating means is set according to the nip length in the circumferential direction of the pair of rollers.

Furthermore, a recording medium coating apparatus for forming a coating layer on the surface of the recording medium,
Recording medium supply means for supplying the recording medium to the covering sheet;
Coating layer forming means for forming a coating layer on the surface of the recording medium by heating and pressurizing the recording medium and the coating sheet,
The coating layer forming means includes a pair of rollers, and at least one of the rollers includes a roller heating means that extends in the axial direction thereof, and the heating ability in the axial direction is adjusted.
To set the heating power distribution in the axial direction in the roller heating means,
The nip length is long corresponding to the nip length in the circumferential direction of the pair of rollers in the pressurized state with respect to the heating power distribution capable of making the roller surface temperature in the axial direction in the non-pressed state uniform. It is preferable that the heating ability in the part is set to be lower by about 5 to 10%, for example.

In the recording medium coating apparatus according to the present application, the recording medium supplied by the recording medium supply unit is heated and pressurized in a sandwiched state by the coating layer forming unit together with the coating sheet. And
The coating layer forming means is composed of a pair of rollers, and at least one of the rollers includes a roller heating means that extends in the axial direction and whose heating ability in the axial direction is distributed. Therefore, the distribution of the surface temperature in the roller axis direction depends on the distribution of the heating ability of the roller heating means in the roller axis direction.

  Here, if the heating ability of the heating means is uniform in the roller axial direction, heat is easily radiated at the roller end, so that both ends of the roller are relatively low temperature, and the temperature on the center side is relatively high. Therefore, conventionally, in the heating means, the heating ability at both ends is higher than the heating ability at the center. That is, the heating power distribution in the roller axial direction of the roller heating means can be made uniform in the roller surface temperature in the axial direction in a non-pressurized state (a state where no nip is generated between the pair of rollers). Distribution.

However, when such a distribution is adopted, a phenomenon occurs in which the temperature distribution of the recording medium and the covering sheet after being heated by the actual roller is high at both ends of the roller. As a result of earnest investigations by the inventors, as a result of the nip length in the circumferential direction of the paired rollers being different in the roller axial direction in the pressurized state, recording between the rollers and between the rollers and these rollers is performed. It was confirmed that this phenomenon occurred due to the influence of the heat transfer state between the medium and the cover sheet.
That is, the roller end portion side with a relatively long nip length has a relatively long time for contact and heat transfer to the recording medium and the cover sheet, and the roller center side with a short nip length has a relatively short length. As a result, if a heating structure is adopted in which the temperature distribution is uniform in the roller axial direction on the roller surface in the non-pressurized state, the temperature at both ends increases in the pressurized state.

  Therefore, in order to set the heating power distribution in the axial direction in the roller heating means, the pressure state is taken into consideration. That is, when the pressure is high, the nip length becomes long, and when the pressure is small, the nip length becomes short. The roller surface temperature in the state can be taken.

Furthermore, by determining the heating power distribution in the roller heating means in the roller axial direction corresponding to the nip length in the circumferential direction of the pair of rollers, appropriate heating can be similarly realized in a pressurized state.
FIG. 16 shows the axial direction of the roller as the horizontal axis and the nip length in the circumferential direction of the roller as the vertical axis. FIG. 16A shows the pressing force (pressing force) in the first pressurizing mechanism 8 described later. The distribution in the roller axis direction of the nip length in the case of 9.65 kg / cm ² is (b) is the nip in the case of 5.27 kg / cm ² which is the pressing force (pressing force) in the second pressure mechanism 10. It shows the distribution in the length of the roller axis.

As can be seen from these figures, the nip length is longer at both ends in the roller axis direction, which is the horizontal direction in the figure, and the temperature at both ends increases accordingly.
Therefore, in an unpressurized state, with respect to the heating power distribution in the same direction in the roller heating means that can make the surface temperature distribution of the roller uniform in the roller axial direction, an amount corresponding to the above nip length, both ends By making it so low, the roller surface temperature distribution in the pressurized state can be made uniform. According to the study by the inventors, for example, when the temperature is about 100 ° C. and the applied pressure is about 10 kg / cm ² , both ends may be set 5 to 15% lower than the center side, and the temperature is about 90 ° C. When the applied pressure is about 5 kg / cm ² , both end sides may be set 2 to 10% lower than the center side.
By doing in this way, the coating layer formation in a roller axial direction can be performed on a thermally uniform condition, and a favorable coating layer can be obtained.

  In the recording medium coating apparatus described above, an example in which a coating layer forming unit for forming a coating layer is provided and a roller heating unit is provided in a roller provided in this unit has been shown. When the sheet constituting the recording medium is a raster paper having irregularities on the surface, there may be a problem that air bubbles remain between the coating layer and the paper even when the coating layer is formed. In such a case, coating layer reprocessing means for heating and pressurizing the recording medium on which the coating layer is formed is provided on the lower side of the coating layer forming means. The roller configuration and heating structure of the coating layer reprocessing means are substantially the same as those of the coating layer forming means.

  And when this coating layer reprocessing means is provided, the pressurizing force in the coating layer reprocessing means is set lower than the pressing force in the multi-layer forming means in order to avoid damage to the coating layer in the reprocessing.

  In the case of this configuration, the average nip length decreases on the coating layer reprocessing means side according to the applied pressure. Therefore, regarding the heating power distribution adjustment in the roller axis direction, the rate of decrease in the heating power distribution at both ends where the nip length is longer is higher than the rate of decrease in the coating layer reprocessing unit. By setting, uniform heating can be realized.

  And as a structure of a roller, this is a hollow cylindrical roller, The structure by which the roller heating means is provided in the inside of the roller is employable.

As a configuration of the roller, it is preferable that the roller surface is a metal roller whose surface is covered with a rubber member having a layer thickness of 1 to 2 mm.
Furthermore, the deurometer hardness (A type) of this rubber member is preferably in the range of 60-80. In the following notation, all rubber hardnesses shall be deurometer hardness (A type).

The reason why the thickness of the rubber layer and the rubber hardness are appropriate will be described from the following two experimental results.
Table 1 below shows the effects of both from the influence of roller deformation and transfer (generation of wrinkles, etc.) (Test 1). Table 2 shows the control of the roller surface temperature. (Test 2).
In both tests, the rubber used was silicon rubber, and the applied pressure was 12 kg / cm ² .

1 Test 1 Roller Deformation and Effect on Transfer In this test, the thickness of the rubber surface layer was changed and the hardness of the rubber was changed. The evaluation criteria were as follows.
○: Does not affect the transfer.
Δ: The roller is deformed but can be used because it does not affect the transfer.
X: Transfer is affected by deformation of the roller.

2 Test 2 Temperature controllability In this test, the thickness of the rubber surface layer was changed and the hardness of the rubber was changed. The evaluation criteria were as follows.
X: Temperature is difficult to stabilize.
Δ: Stable but takes time.
○: No problem.

  From the above results, it is considered that as the rubber thickness increases, the thermal conductivity to the roller surface deteriorates, and the roller surface temperature important at the transfer temperature becomes unstable. Further, in this state, since the metal roller is heated until reaching the set temperature, even if the roller surface temperature (rubber surface temperature) reaches the set temperature, it overshoots greatly and takes time to stabilize. Therefore, by reducing the rubber thickness to 1 to 2 mm, the temperature difference between the roller surface temperature and the metal roller can be reduced, and the temperature control becomes stable.

Here, when the rubber thickness is less than 1 mm, it is substantially the same as the state in which the rubber layer is not provided.
On the other hand, when the hardness of the rubber is lower than 60, it is not preferable because it causes deformation of the rubber layer, and when it is higher than 80, the rubber surface layer is not provided, which is not preferable.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is an external perspective view of the coating apparatus according to this embodiment with a cover attached, FIG. 2 is a perspective view of the coating apparatus according to this embodiment with the cover removed, and FIG. FIG. 4 is a cross-sectional perspective view of the coating apparatus according to the embodiment cut near the center in the width direction (with the cover removed), and FIG. 4 is a cross-sectional view of the coating apparatus according to the present embodiment cut near the center in the width direction.

  As shown in these drawings, in the coating apparatus according to the present embodiment, the recording paper A is supplied into the apparatus main body along the supply tray 1 and the supply guide 2 continuous therewith. 4, a coating layer is formed on the surface while being transported along a transport path L provided in the horizontal direction, and is discharged to a discharge tray 4 by a discharge mechanism 3 described later. At this time, the recording paper A is conveyed with the recording surface on which the image is recorded facing upward, and the coating apparatus is configured to form a coating layer on the recording surface. Therefore, in the present embodiment, the recording paper A constitutes the “recording medium” in the present invention, and the supply tray 1 and the supply guide 2 constitute the “recording medium supply unit 5” in the present invention.

  In the apparatus main body of the coating apparatus, a coating sheet conveyance mechanism 6 that conveys the coating sheet B, an auxiliary sheet conveyance mechanism 7 that conveys the auxiliary sheet E, and a coating sheet B and an auxiliary sheet E that sandwich the recording paper A therebetween. Are pressed from both sides, a first branch guide 9 for branching the conveyance path of the recording paper A and the conveyance path of the covering sheet B, and the base material C of the covering sheet B are separated and covered. The second pressurizing mechanism 10 that further pressurizes the recording paper A and the auxiliary sheet E after the formation of the layer F from both sides, and the second branch that branches the transport path of the recording paper A and the transport path of the auxiliary sheet E. A guide 11 and a discharge mechanism 3 for discharging the recording paper A after the auxiliary sheet E is separated to the discharge tray 4 are provided. These components are integrally supported by the main body frame 12. Hereinafter, these configurations will be described in detail.

  As shown in FIG. 5, the covering sheet B used in the covering apparatus according to the present embodiment includes a base material C and a transfer layer D that can be peeled on one surface. The transfer layer D is a portion that is transferred to the recording surface of the recording paper A to form a coating layer F, and is provided on the base material C and plays a main role for protecting the recording surface of the recording paper A. The protective layer D1 is provided on the outer side of the protective layer D1 and has an adhesive layer D2 for adhering the protective layer D1 to the recording surface of the recording paper A. Further, here, in order to maintain the bonding state between the protective layer D1 and the adhesive layer D2, an anchor layer D3 is provided between them.

  Since the transfer layer D of the covering sheet B is a covering layer for protecting the recording surface of the recording paper A, it has excellent adhesion to the recording paper A, is highly transparent, hardly discolored by heat and light, It is preferable that the physical barrier property is excellent. As will be described later, when the recording sheet A and the auxiliary sheet E are separated from each other after forming the coating layer F by being transferred onto the recording surface of the recording sheet A and the surface of the auxiliary sheet E around the recording sheet A. In addition, a material and a thickness that can be separated along the vicinity of the edge of the recording paper A from the portion formed on the recording surface of the recording paper A and the portion formed on the surface of the auxiliary sheet E around the recording paper A. Is preferable. Therefore, it is preferable to use, for example, an acrylic resin, a vinyl acetate resin, or the like for the protective layer D1. Here, as will be described later, since the first pressurizing mechanism 8 is configured to pressurize and heat the covering sheet B and the auxiliary sheet E sandwiching the recording paper A from both sides, the adhesive layer D2 includes It is preferable to use a thermoplastic resin such as a polyester resin that has transparency and exerts an adhesive force when heated. The base material C of the covering sheet B has heat resistance and mechanical strength that can stably maintain the shape under the pressurization and heating conditions in the first pressurization mechanism 8 described later, and good peeling from the transfer layer D. It is preferable to have the property. Therefore, for the substrate C, for example, a film of polyethylene terephthalate, polypropylene, polyethylene naphthalate or the like is preferably used.

  Further, the cover sheet B has a constant width that is larger than the width of the recording paper A (the width of the recording paper A having the maximum width in the case of recording paper A having a plurality of types of width). The long sheet is used. In the present embodiment, as the covering sheet B, a sheet wound in a roll shape with the base material C as the outside and the transfer layer D as the inside is used. Thus, the cover sheet B is transported by the cover sheet transport mechanism 6 in a direction in which the transfer layer D faces the auxiliary sheet E.

  As illustrated in FIGS. 1 to 4, the cover sheet transport mechanism 6 includes a supply holding unit 6 a that holds the cover sheet B wound in a roll shape so that the cover sheet B can be supplied, and a transport path of the recording paper A by the first branch guide 9. And a base material recovery part 6b that winds and recovers the base material C of the covering sheet B after the transfer layer D is peeled off. In the present embodiment, the supply holding unit 6a is supported at both ends by the main body frame 12, and holds the cover sheet B wound up in a roll shape so as to be rotatable, and restricts the rotation of the holding shaft 6c. A rotation limiting mechanism 6d. As the rotation limiting mechanism 6d, for example, a configuration including a torque limiter between the main body frame 12 and the holding shaft 6c is preferably used. The covering sheet B is pulled out by the rotation of a driving roller 8a of the first pressure mechanism 8 (to be described later) and the pressure roller 8b that follows the first pressure mechanism 8. At this time, the rotation of the holding shaft 6c is limited by the rotation limiting mechanism 6d. Therefore, the tension of the covering sheet B from the supply holding unit 6a to the pressure roller 8b of the first pressure mechanism 8 can be maintained. A free roller 6e is rotatably provided between the supply holding unit 6a and the conveyance path L for the recording paper A. The free roller 6e adjusts the intrusion angle of the conveyance path of the cover sheet B at a portion where the cover sheet B merges with the conveyance path L of the recording paper A by winding the cover sheet B around the outer periphery thereof in a predetermined angle range. The transport path of the cover sheet B after joining the transport path L of the recording paper A is provided to coincide with the transport path L of the recording paper A up to the branch position by the first branch guide 9.

  Further, the base material collecting unit 6b is a winding that is rotationally driven in a predetermined direction in order to take up and collect the base material C of the covering sheet B after being branched from the conveyance path of the recording paper A by the first branch guide 9. A take-up shaft 6f, a take-up shaft drive mechanism 6g for driving the take-up shaft 6f, and a drive limiting mechanism 6h for limiting the driving force transmitted from the take-up shaft drive mechanism 6g to the take-up shaft 6f. Have. In the present embodiment, as shown in FIG. 2, each part of the coating apparatus is driven by a driving force from a single motor 13 being transmitted by a transmission mechanism such as a plurality of sprockets, chains and gears. ing. Therefore, the take-up shaft drive mechanism 6g includes a motor 13 that drives the entire coating apparatus, and a transmission mechanism that transmits the driving force of the motor 13 to the take-up shaft 6f. Further, as the drive limiting mechanism 6h, for example, a structure provided with a torque limiter between a transmission mechanism such as a gear constituting the take-up shaft drive mechanism 6g and the take-up shaft 6f is preferably used. Here, the rotational speed of the take-up shaft 6f driven by the take-up shaft drive mechanism 6g in a state that is not restricted by the drive restriction mechanism 6h is obtained by winding the base material C around the take-up shaft 6f. Even when the diameter of the outer periphery changes, the peripheral speed of the outer periphery of the base material C wound around the winding shaft 6 f becomes faster than the peripheral speed of the outer periphery of the driving roller 8 a of the first pressure mechanism 8. Is set to Specifically, the base material C is hardly wound around the winding shaft 6f, and the peripheral speed in the state where the peripheral speed of the outer periphery of the base material C is the slowest is the driving of the first pressurizing mechanism 8. It is preferable that the speed is equal to or slightly faster than the peripheral speed of the outer periphery of the roller 8a. At this time, since the conveyance speed V1 of the base material C of the cover sheet B is determined by the peripheral speed of the outer periphery of the drive roller 8a of the first pressure mechanism 8, the outer periphery of the base material C wound around the winding shaft 6f. The tension of the base material C is maintained by the speed difference from the peripheral speed, and the speed difference is absorbed by being restricted by the drive restriction mechanism 6h so as not to transmit a certain driving force to the winding shaft 6f. The

  The auxiliary sheet E used in the coating apparatus according to the present embodiment transfers the transfer layer D of the cover sheet B onto the recording surface of the recording sheet A to form the cover layer F, In the portion where the recording paper A does not exist between the plurality of recording papers A, the transfer layer D of the covering sheet B conveyed oppositely is a sheet to which the recording sheet A is transferred. Therefore, as the material of the auxiliary sheet E, it is preferable to use a material to which the adhesive layer D2 provided on the surface of the transfer layer D of the covering sheet B can easily adhere. Therefore, for example, it is preferable to use a film such as polyethylene terephthalate.

  Further, the auxiliary sheet E is equal to the width of the covering sheet B in order to prevent the transfer layer D from protruding from the side edge of the auxiliary sheet E when transferring the transfer layer D of the covering sheet B. It shall have the above width. In the present embodiment, as the auxiliary sheet E, a long sheet having a certain width that is slightly wider than the width of the covering sheet B and being wound in a roll shape is used. As a result, the entire lower surface (transfer surface) of the cover sheet B faces the upper surface of the auxiliary sheet E, so that the transfer layer D of the cover sheet B is transferred to the drive roller 8 a of the first pressure mechanism 8. This can be prevented.

  The auxiliary sheet conveyance mechanism 7 includes a supply holding unit 7a that holds the auxiliary sheet E wound in a roll shape so that the auxiliary sheet E can be supplied, and the auxiliary sheet E after being branched from the conveyance path of the recording paper A by the second branch guide 11. And a sheet collecting section 7b that winds and collects the sheet. In the present embodiment, the supply holding unit 7a is supported by the main body frame 12 at both ends, the holding shaft 7c that rotatably holds the auxiliary sheet E wound in a roll shape, and the rotation of the holding shaft 7c is limited. A rotation limiting mechanism 7d. As the rotation limiting mechanism 7d, for example, a configuration including a torque limiter between the main body frame 12 and the holding shaft 7c is preferably used. The auxiliary sheet E is pulled out by the rotation of a driving roller 8a of the first pressure mechanism 8 described later and the pressure roller 8b driven by the auxiliary sheet E. At this time, the rotation of the holding shaft 7c is limited by the rotation limiting mechanism 7d. Therefore, the tension of the auxiliary sheet E from the supply holding unit 7a to the driving roller 8a of the first pressure mechanism 8 can be maintained. A free roller 7e is rotatably provided between the supply holding unit 7a and the conveyance path L for the recording paper A. The free roller 7e adjusts the intrusion angle of the conveyance path of the auxiliary sheet E at the portion joining the conveyance path L of the recording paper A by winding the auxiliary sheet E around the outer periphery of the free roller 7e in a predetermined angle range. Then, the conveyance path L of the auxiliary sheet E after joining the conveyance path L of the recording paper A reaches the branching position by the second branch guide 11 on the downstream side of the second pressurizing mechanism 10. Is provided to match. At this time, the auxiliary sheet E is conveyed opposite to the covering sheet B with the recording paper A sandwiched between the auxiliary sheet E and the covering sheet B until the branch position of the conveying path of the covering sheet B by the first branch guide 9. The

  Further, the sheet collecting unit 7b includes a take-up shaft 7f that is rotationally driven in a predetermined direction in order to take up and collect the auxiliary sheet E branched from the conveyance path L of the recording paper A by the second branch guide 11. A take-up shaft drive mechanism 7g for driving the take-up shaft 7f and a drive limiting mechanism 7h for restricting the driving force transmitted from the take-up shaft drive mechanism 7g to the take-up shaft 7f are provided. . In the present embodiment, as shown in FIG. 2, the take-up shaft drive mechanism 7g includes a motor 13 that drives the entire coating apparatus, and a plurality of force that transmits the driving force of the motor 13 to the take-up shaft 7f. It is composed of transmission mechanisms such as sprockets, chains and gears. As the drive limiting mechanism 7h, for example, a structure including a torque limiter between a transmission mechanism such as a gear constituting the take-up shaft drive mechanism 7g and the take-up shaft 7f is preferably used. Here, the rotational speed of the take-up shaft 7f driven by the take-up shaft drive mechanism 7g in a state that is not restricted by the drive restriction mechanism 7h is obtained by winding the auxiliary sheet E around the take-up shaft 7f. Even when the outer diameter changes, the peripheral speed of the outer periphery of the auxiliary sheet E wound around the winding shaft 7f becomes faster than the peripheral speed of the outer periphery of the driving roller 10a of the second pressure mechanism 10. Is set. Specifically, the auxiliary sheet E is hardly wound around the winding shaft 7 f, and the peripheral speed in the state where the peripheral speed of the outer periphery of the auxiliary sheet E is the slowest is the driving of the second pressurizing mechanism 10. The speed is preferably equal to or slightly faster than the peripheral speed of the outer periphery of the roller 10a. At this time, the conveyance speed V1 of the auxiliary sheet E is determined by the peripheral speed of the outer periphery of the driving roller 10a of the second pressure mechanism 10 and the driving roller 8a of the first pressure mechanism 8 rotating at the same speed. The tension of the auxiliary sheet E is maintained by the speed difference from the peripheral speed of the outer periphery of the auxiliary sheet E wound around the shaft 7f, and the speed difference is more than a certain value with respect to the winding shaft 7f by the drive limiting mechanism 7h. It is absorbed by being limited so as not to transmit the driving force.

  The recording sheet A is interposed between the covering sheet B and the auxiliary sheet E conveyed opposite to each other by the covering sheet conveying mechanism 6 and the auxiliary sheet conveying mechanism 7 as described above via the supply tray 1 and the supply guide 2. The recording sheet A, the cover sheet B, and the auxiliary sheet E are supplied and pressed from both sides by the first pressurizing mechanism 8 in a stacked state.

The first pressure mechanism 8 includes a driving roller 8a that is rotationally driven in the conveyance direction of the recording paper A, the covering sheet B, and the auxiliary sheet E, a roller driving mechanism 8c that rotationally drives the driving roller 8a, and a driving roller 8a. And a pressure roller 8b that is in contact with the drive roller 8a in a pressurized state and that is rotated by the rotation of the drive roller 8a, and the pressure roller 8b is applied to the drive roller 8a side. And a pressurizing mechanism 8d for pressing. In the present embodiment, both the driving roller 8a and the pressure roller 8b are configured such that the surface of a hollow metal roller is covered with an elastic member such as silicon rubber. The thickness of the elastic member covering the surface of the metal roller does not impair the thermal conductivity from the heater provided inside the metal roller, as will be described later, and the drive roller 8a and the pressure roller 8b It is preferable that the thickness of the recording sheet A, the covering sheet B, and the auxiliary sheet E transported between them is sufficiently thick so that the recording sheet A and the auxiliary sheet E can be sufficiently pressed. For example, in the case of silicon rubber, about 1-2 mm. It is preferable to have a thickness of. The hardness may be a common 60-80. In this embodiment, as shown in FIG. 2, the roller driving mechanism 8c includes a motor 13 that drives the entire coating apparatus, and a plurality of sprockets and chains that transmit the driving force of the motor 13 to the driving roller 8a. And a transmission mechanism such as a gear. 1-4, as shown in FIGS. 1-4, the holding member 8e which hold | maintains the both ends of the rotating shaft of the pressure roller 8b so that a displacement is possible to an up-down direction, and urges | biases this holding member 8e below. And an urging member 8f configured by an elastic member such as a spring. In this embodiment, the pressure applied by the pressure mechanism 8d is set so that the pressure at the nip portion between the driving roller 8a and the pressure roller 8b is about 8 to 12 kg / cm ² .

  In addition, heaters 8g are respectively provided inside the driving roller 8a and the pressure roller 8b of the first pressure mechanism 8, and heat the recording paper A, the cover sheet B, and the auxiliary sheet E while applying pressure. It has a configuration. In the present embodiment, a halogen lamp is disposed as the heater 8g at the axial center of each of the drive roller 8a and the pressure roller 8b. In this embodiment, the heating temperature by the heater 8g is set to be about 90 to 110 ° C. for the pressure roller 8b and about 50 to 70 ° C. for the driving roller 8a.

The setting method of the roller surface temperature in the pressure roller 8b and the driving roller 8a will be described in more detail.
As shown in FIGS. 3 and 4 and described above, each of the rollers 8a and 8b is formed in a pair of hollow cylinders and extends in the axial direction inside the rollers, and the heating ability in the axial direction is distributed and adjusted. The halogen lamp 8g is provided. This halogen lamp 8g constitutes “roller heating means” in the present application.

As shown in FIG. 7, the halogen lamp 8g is configured by enclosing halogen in a long glass tube 8g1, and is configured to include a filament 8g2. This filament has a densely wound portion 8g21 and a loosely wound portion 8g22 that are sparsely wound in order to obtain a distribution of heating ability in the lamp axis direction. As a result, the heating ability at the densely wound portion 8g21 can be set relatively high, and the heating ability at the loosely wound portion 8g22 can be set relatively low. Basically, the length of the closely wound portion 8g21 is increased as it is located on both ends.
As shown in FIG. 1, the halogen lamp 8g has a configuration in which the power line 8g3 is led out from the end of each roller and connected to the power source (not shown) side.

  With the above configuration, the halogen lamp 8g employed in the present application can set the heating power in a desired distribution in the axial direction. The heating power distribution setting method in the present application will be described in detail below. explain.

  When the heating means 8g is provided in the hollow cylindrical roller and the heating ability of the heating means 8g is equal in the roller axial direction, the gas flow between the inner and outer spaces of the roller is generated relatively freely at the roller end. Therefore, both end sides 8ae are relatively low temperature, and the temperature of the central 8ac portion is relatively high. Therefore, conventionally, in consideration of this requirement, in the heating means 8g, the heating ability at both ends thereof is higher than the heating ability at the center side (parts where the length of the densely wound portion is long are provided at both ends). ) The temperature change in the roller axis direction of the roller surface temperature should be minimized. Under this condition, in order to set the heating power distribution in the roller axial direction in the roller heating means 8g, the roller surface temperature in the axial direction in the non-pressurized state is a heating power distribution that can be a uniform distribution.

However, when such a distribution is adopted, since the temperature distribution caused only by the flow of the heated gas in the roller is taken into consideration, the heating to the actual coating layer in the pressurized state is caused by the nip length. Therefore, as described above, a phenomenon occurs that the roller both ends 8ae are high.
Therefore, in order to set the heating power distribution in the axial direction in the roller heating means 8g, the heating surface distribution in the axial direction in the non-pressurized state is set in a pressurized state with respect to the heating power distribution that can be a uniform distribution. Corresponding to the nip length in the circumferential direction of the pair of rollers, the heating ability at both ends is set to be 5 to 10% lower. By adopting such a setting method, the temperature distribution on the roller surface in the roller axis direction can be suppressed to about 12 ° C. for the driving roller 8a and about 6 ° C. for the pressure roller 8b as shown in FIG. It became.

  As a result, this structure is such that the heating power distribution in the roller axial direction of the roller heating means 8g is set in consideration of the state in which the pressure is applied, and at the same time, the nip in the circumferential direction of the pair of rollers. It is set according to the length.

  Therefore, in the first pressure mechanism 8, the recording paper A, the cover sheet B, and the auxiliary sheet E are pressed and heated from both sides while being conveyed in a laminated state between the driving roller 8a and the pressure roller 8b. . By this heating and pressurization, the transfer layer D of the covering sheet B adheres to the recording surface of the recording sheet A sandwiched between the covering sheet B and the auxiliary sheet E and the surface of the auxiliary sheet E around the recording sheet A. Is done. That is, the adhesive layer D2 constituting the transfer layer D of the covering sheet B is activated by heating, and is further pressed by the pressure of the driving roller 8a and the pressure roller 8b of the first pressure mechanism 8. As a result, the transfer layer D is adhered to the recording surface of the recording paper A and the surface of the auxiliary sheet E around the recording paper A. Then, the substrate C of the covering sheet B is peeled off from the recording sheet A and the auxiliary sheet E by branching the conveying path of the recording sheet A and the conveying path of the covering sheet B in the first branch guide 9 described later. The transfer layer D is transferred onto the recording surface of the recording paper A and the surface of the auxiliary sheet E around the recording paper A. This transfer layer D forms a coating layer F. Therefore, in the present embodiment, the first pressurizing mechanism 8 and the first branch guide 9 constitute the “coating layer forming means 14” in the present invention.

  The first branch guide 9 is provided between the first pressure mechanism 8 and the second pressure mechanism 10 in the transport path L of the recording paper A, and the transport path L of the recording paper A and the base material C of the cover sheet B. It is a guide member which branches the conveyance path. In the present embodiment, as shown in FIGS. 9 and 10, the first branch guide 9 is configured by a member extending in a direction substantially perpendicular to the conveyance direction of the recording paper A on the conveyance path L of the recording paper A, On the lower side, a first guide surface 9a is formed that is arranged substantially in parallel with the conveyance path L of the recording paper A, and an acute angle is formed on the downstream side in the conveyance direction of the recording paper A with respect to the first guide surface 9a. A second guide surface 9b is formed so as to extend upward. Then, as shown in FIG. 10, the base material C of the covering sheet B is peeled from the recording paper A and the auxiliary sheet E at the edge 9c where the first guide surface 9a and the second guide surface 9b are in contact with each other. The base material C is conveyed along the second guide surface 9b and is wound and collected by the base material collection unit 6b. As a result, the coating layer F is formed on the recording surface of the recording paper A and the surface of the auxiliary sheet E around the recording paper A. The first branch guide 9 has a distance such that the adhesive layer D2 of the covering sheet B activated by the heating by the first pressure mechanism 8 is cooled and exhibits a sufficient adhesive force. It is suitable to arrange so that it has with respect to 8.

The second pressurizing mechanism 10 is opposed to the driving roller 10a that is rotationally driven in the conveyance direction of the recording paper A and the auxiliary sheet E, the roller driving mechanism 10c that rotationally drives the driving roller 10a, and the driving roller 10a. A pressure roller 10b which is provided and is in contact with the drive roller 10a in a pressurized state and which is rotated by the rotation of the drive roller 10a, and a pressure mechanism which pressurizes the pressure roller 10b toward the drive roller 10a. 10d. In the present embodiment, both the driving roller 10a and the pressure roller 10b are configured such that the surface of a hollow metal roller is covered with an elastic member such as silicon rubber. The thickness of the elastic member covering the surface of the metal roller does not impair the heat conductivity from the heater provided inside the metal roller, as will be described later, and the drive roller 10a and the pressure roller 10b It is preferable that the recording paper A and the auxiliary sheet E on which the coating layer F to be transported is formed have such a thickness as to have sufficient elasticity so that, for example, in the case of silicon rubber, the thickness is 1 A thickness of about ˜2 mm is preferable. The hardness may be a common 60-80. In this embodiment, as shown in FIG. 2, the roller driving mechanism 10c includes a motor 13 that drives the entire coating apparatus, and a plurality of sprockets and chains that transmit the driving force of the motor 13 to the driving roller 10a. And a transmission mechanism such as a gear. Here, the transmission mechanism is set so that the peripheral speed of the outer periphery of the drive roller 8a of the first pressure mechanism 8 and the peripheral speed of the outer periphery of the drive roller 10a of the second pressure mechanism 10 are substantially the same. Yes. Further, as shown in FIGS. 2 to 4, the pressure mechanism 10 d includes a holding member 10 e that holds both ends of the rotation shaft of the pressure roller 10 b so as to be displaceable in the vertical direction, and urges the holding member 10 e downward. And an urging member 10f composed of an elastic member such as a spring. In this embodiment, the pressure applied by the pressure mechanism 10d is set so that the pressure at the nip portion between the driving roller 10a and the pressure roller 10b is about 3 to 7 kg / cm ² .

Further, a heater 10g is provided in the pressure roller 10b of the second pressure mechanism 10, and the recording paper A and the auxiliary sheet E on which the coating layer F is formed are heated while being pressurized. ing. On the other hand, no heater is provided on the drive roller 10a side.
In the present embodiment, a halogen lamp is disposed in the axial center portion of the pressure roller 10b as the heater 10g. In this embodiment, the heating temperature by the heater 10g is set to be about 80 to 100 ° C. as the surface temperature of the pressure roller 10b. Regarding the heating power distribution in the halogen lamp 10g, the heating power distribution is set in consideration of the relationship between the cooling accompanying the gas flow at the roller end and the heat transfer depending on the nip length in the circumferential direction.
However, in the comparison between the first pressurizing mechanism 8 and the second pressurizing mechanism 10, the latter pressurizing force is set smaller than the former pressurizing force. The influence of is set small. That is, in the first pressurizing mechanism 8, the rate of decrease in the heating power distribution at both ends is selected to be 5 to 15%, whereas in the second pressurizing mechanism 10, the lower rate is 2 to 10%. Is selected.

Accordingly, the second pressurizing mechanism 10 has a configuration in which the recording paper A and the auxiliary sheet E on which the coating layer F is formed are pressurized from both sides while being conveyed and heated from the surface on the coating layer F side. By this heating and pressurization, the coating layer F formed on the recording surface of the recording paper A and the surface of the auxiliary sheet E around the recording paper A is pressed and firmly bonded without any gap.
The second pressurizing mechanism 10 constitutes a coating layer reprocessing means for reprocessing the coating layer F formed on the recording medium A in the present application.

  The second branch guide 11 is a guide member that is provided on the downstream side of the second pressure mechanism 10 in the transport path L of the recording paper A, and branches the transport path L of the recording paper A and the transport path of the auxiliary sheet E. . In the present embodiment, as shown in FIG. 11, the second branch guide 11 is configured by a member that extends in a direction substantially perpendicular to the conveyance direction of the recording paper A on the conveyance path L of the recording paper A. Is formed with a first guide surface 11a disposed substantially in parallel with the conveyance path L of the recording paper A, and at a downstream side in the conveyance direction of the recording paper A, the first guide surface 11a forms an acute angle downward with respect to the first guide surface 11a. A second guide surface 11b provided to extend is formed. Then, as shown in FIG. 12, the auxiliary sheet E is peeled from the recording paper A at the edge 11c where the first guide surface 11a and the second guide surface 11b are in contact, and the peeled auxiliary sheet E is the second guide. The sheet is conveyed along the surface 11b and wound and collected by the sheet collecting unit 7b. At this time, the recording sheet A advances straight in the horizontal direction along the conveyance path L, while the auxiliary sheet E is bent and conveyed downward along the second guide surface 11 b of the second branch guide 11. Therefore, the coating layer F formed on the recording surface of the recording paper A and the coating layer F formed on the surface of the auxiliary sheet E around the recording paper A are separated from each other. The coating layer F formed on the surface and the coating layer F formed on the surface of the auxiliary sheet E around the recording paper A are cut and separated along the vicinity of the edge of the recording paper A.

  2 to 4 and 11, the discharge mechanism 3 is provided on the downstream side of the second branch guide 11 in the conveyance path L of the recording paper A, and the auxiliary sheet E is separated in the second branch guide 11. This is a transport mechanism of the recording paper A for discharging the subsequent recording paper A to the discharge tray 4. Here, a driving roller 3a that is rotationally driven in the conveyance direction of the recording paper A, a roller driving mechanism 3c that rotationally drives the driving roller 3a, and a driving roller 3a that are provided opposite to the driving roller 3a, are added to the driving roller 3a. The pressure roller 3b is in contact with the pressure roller and is rotated by the rotation of the drive roller 3a, and the pressure mechanism 3d presses the pressure roller 3b toward the drive roller 3a. In the present embodiment, the drive roller 3a and the pressure roller 3b are both constituted by rollers whose surfaces are covered with an elastic member such as synthetic rubber. These rollers can be metal hard rollers that are not covered with a rubber member. In this embodiment, as shown in FIG. 2, the roller driving mechanism 3c includes a motor 13 that drives the entire coating apparatus, and a plurality of sprockets and chains that transmit the driving force of the motor 13 to the driving roller 3a. And a transmission mechanism such as a gear.

  In the present embodiment, the pressing mechanism 3d, as shown in FIG. 11, is an urging member 3f configured by an elastic member such as a spring that urges both ends of the rotating shaft of the pressing roller 3b downward. It is comprised. The pressure applied by the pressurizing mechanism 3d is such that the drive roller 3a slides against the back surface of the recording paper A until the vicinity of the rear end of the recording paper A is separated from the auxiliary sheet E. After the vicinity of the edge is separated from the auxiliary sheet E, it is preferable that the pressure is such that the driving roller 3a and the recording paper A are conveyed without slipping.

Specifically, the pressure at the nip portion between the drive roller 3a and the pressure roller 3b is set to 0.5 to ³ kg / cm ² . That is, in this embodiment, the force in the transport direction applied to the recording paper A can be limited by adjusting the pressure applied by the pressurizing mechanism 3d. Therefore, it is desirable that the pressurizing mechanism 3d has a configuration in which the pressing force can be finely adjusted by making it possible to adjust the attachment position of the urging member 3f.

  As a result, the position where the recording sheet A and the auxiliary sheet E separate from each other is too upstream with respect to the branching position between the conveyance path L of the recording sheet A and the conveyance path of the auxiliary sheet E by the second branch guide 11. As a result, it is possible to prevent an excessive force from acting on the coating layer F and the quality of the recording paper A after coating from being deteriorated. FIG. 12 shows a state before separation, and FIG. 13 shows a state after separation. It can be seen that the speed of the recording medium A is accelerated from V1 to V2.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
FIG. 14 is a cross-sectional view of the coating apparatus according to the present embodiment, cut near the center in the width direction. As shown in this figure, the coating apparatus according to the present embodiment does not include a portion corresponding to the second pressurizing mechanism 10 in the coating apparatus according to the first embodiment, and recording by the first branch guide 9. The branch position of the transport path of the paper A and the transport path of the base material C of the cover sheet B and the branch position of the transport path L of the recording paper A and the transport path of the auxiliary sheet E by the second branch guide 11 are close to each other. It is mainly different from the first embodiment in that it is a position.

  That is, in the present embodiment, the recording paper A, the cover sheet B, and the auxiliary sheet E are conveyed from both sides while being conveyed in a laminated state between the driving roller 8a and the pressure roller 8b of the first pressure mechanism 8. By applying pressure and heating, the transfer layer D of the covering sheet B is adhered to the recording surface of the recording paper A and the surface of the auxiliary sheet E around the recording paper A. Also in this example, as described in the first embodiment, the heating amount distribution in the roller axis direction is taken into account the nip length in the pressurized state.

  Thereafter, the conveyance path L of the recording paper A and the conveyance path of the base material C of the covering sheet B are branched by the first branch guide 9 disposed at such a distance that the adhesive layer D2 of the covering sheet B is cooled. Thus, as shown in FIG. 15, the base material C of the covering sheet B is peeled off from the recording paper A and the auxiliary sheet E to cover the recording surface of the recording paper A and the surface of the auxiliary sheet E around the recording paper A. Layer F is formed. The second branch guide 11 is arranged at a very close position on the downstream side in the conveyance direction of the recording paper A, and the conveyance path L for the recording paper A and the conveyance path for the auxiliary sheet E by the second branch guide 11. Are separated from each other, and the recording sheet A on which the coating layer F is formed on the recording surface and the auxiliary sheet E on which the coating layer F is formed on the surface around the recording sheet A are separated from each other. The coating layer F formed on the recording surface of the recording paper A and the coating layer F formed on the surface of the auxiliary sheet E around the recording paper A are cut along the vicinity of the edge of the recording paper A and separated. Then, the recording paper A on which the coating layer F is formed is discharged to the discharge tray 4 by the discharge mechanism 3.

  Here, the discharge mechanism 3 is provided on the downstream side of the second branch guide 11 in the conveyance path L of the recording paper A, and is driven by a drive roller 3a that is rotationally driven in the conveyance direction of the recording paper A. A roller driving mechanism 3c that rotates so that the peripheral speed of the outer periphery is faster than the peripheral speed of the outer periphery of the driving roller 8a of the first pressure mechanism 8, and the driving roller 3a. The pressure roller 3b is in contact with the pressure roller 3a and is rotated by the rotation of the drive roller 3a, and the pressure mechanism 3d pressurizes the pressure roller 3b toward the drive roller 3a. In this respect, this embodiment is the same as the first embodiment. However, in this embodiment, a drive limiting mechanism (not shown) for limiting the driving force transmitted from the roller driving mechanism 3c to the driving roller 3a is further provided. I have. As this drive limiting mechanism, for example, a configuration including a torque limiter between a transmission mechanism such as a gear constituting the roller drive mechanism 3c and the rotation shaft of the drive roller 3a is preferably used. In other words, in this embodiment, the force in the transport direction applied to the recording paper A can be limited by limiting the transmission of the driving force by the drive limiting mechanism.

[Other Embodiments]
(1) In the above embodiment, as shown in FIGS. 2 to 4 and 14, the configuration including the supply tray 1 and the supply guide 2 as the “recording medium supply unit 5” in the present invention has been described. The supply unit 5 may include an automatic supply mechanism that automatically and continuously supplies the recording paper A. That is, the coating apparatus according to the present invention is installed on the downstream side of the recording apparatus that records an image on the recording paper A such as a photographic printer in actual use. Therefore, it is preferable that the recording paper A continuously discharged from the recording apparatus is automatically conveyed and supplied into the apparatus main body of the coating apparatus.

(2) In the above embodiment, an example in which a halogen lamp is used to configure the roller heating unit has been described. However, any heating unit may be used as long as the distribution of the heating ability can be adjusted in a predetermined longitudinal direction. Can be used. For example, a hot wire type heater may be employed.

(3) In the above embodiment, the case where the covering sheet B having the base material C and the transfer layer D provided so as to be peelable from the base material C has been described. The sheet is not limited to this, and for example, it is possible to use a sheet that does not include the base material C and includes only a portion corresponding to the transfer layer D. In this case, the covering sheet conveyance mechanism 6 does not include the base material recovery unit 6b.

(4) In the above-described embodiment, the cover sheet B and the auxiliary sheet E are supplied to the recording paper A, and the remaining not used for forming the coating layer F on the recording paper A is removed from the auxiliary sheet E. However, when the continuous recording paper A is processed, the auxiliary sheet E is not particularly required. Even in the configuration in which the coating layer is formed by using only the coating sheet B for this type of recording paper A, the nip length affects the heating temperature distribution in the roller axis direction. Can be adopted.

1 is an external perspective view of a coating apparatus according to a first embodiment of the present invention. The perspective view which removed the cover of the coating | coated apparatus which concerns on the 1st Embodiment of this invention The cross-sectional perspective view which cut | disconnected the coating | coated apparatus which concerns on the 1st Embodiment of this invention in the width direction center vicinity. Sectional drawing which cut | disconnected the coating | coated apparatus which concerns on the 1st Embodiment of this invention near width direction center. Schematic sectional view showing the structure of the covering sheet according to the first embodiment of the present invention Detailed view of the vicinity of the first pressure mechanism Figure showing the external configuration of the halogen lamp The figure which shows distribution of the roller surface temperature obtained in this invention Detailed view of the vicinity of the second pressure mechanism Enlarged view of the vicinity of the first branch guide in FIG. Enlarged view of the vicinity of the second branch guide in FIG. The perspective view which shows the state at the time of an auxiliary sheet peeling from a recording paper in the 2nd branch guide of the coating device which concerns on the 1st Embodiment of this invention. The perspective view which shows the state immediately after the recording paper was pulled away from the auxiliary sheet in the discharge mechanism of the coating apparatus according to the first embodiment of the present invention. Sectional drawing which cut | disconnected the coating | coated apparatus which concerns on the 2nd Embodiment of this invention in width direction center vicinity. The perspective view which shows the state at the time of a recording paper peeling from the base material and auxiliary sheet | seat of a coating sheet in the 1st branch guide and 2nd branch guide of the coating apparatus which concerns on the 2nd Embodiment of this invention. The figure which shows the nip length of the roller with which a 1st pressurization mechanism and a 2nd pressurization mechanism are equipped.

Explanation of symbols

A Recording paper (recording medium)
B Cover sheet C Cover sheet base D Cover sheet transfer layer E Auxiliary sheet F Cover layer L Recording paper transport path 3 Discharge mechanism 5 Recording medium supply means 6 Cover sheet transport mechanism 7 Auxiliary sheet transport mechanism 8 First pressurization Mechanism 8g Roller heating means 9 First branch guide 10 Second pressure mechanism 11 Second branch guide 14 Cover layer forming means

Claims (6)

A recording medium coating apparatus for forming a coating layer on a surface of a recording medium,
Recording medium supply means for supplying the recording medium to the covering sheet;
Heating / pressurizing the recording medium and the covering sheet, and a coating layer forming means for forming a coating layer on the surface of the recording medium,
The coating layer forming means includes a pair of rollers, and at least one of the rollers includes a roller heating means that extends in the axial direction thereof, and the heating ability in the axial direction is adjusted.
A recording medium coating apparatus in which a heating power distribution in the axial direction of the roller heating means is set according to the pressure applied by the roller. A recording medium coating apparatus for forming a coating layer on a surface of a recording medium,
Recording medium supply means for supplying the recording medium to the covering sheet;
Heating / pressurizing the recording medium and the covering sheet, and a coating layer forming means for forming a coating layer on the surface of the recording medium,
The coating layer forming means includes a pair of rollers, and at least one of the rollers includes a roller heating means that extends in the axial direction thereof, and the heating ability in the axial direction is adjusted.
A recording medium coating apparatus in which a heating power distribution in the axial direction of the roller heating unit is set according to a nip length in a circumferential direction of the pair of rollers. A recording medium coating apparatus for forming a coating layer on a surface of a recording medium,
Recording medium supply means for supplying the recording medium to the covering sheet;
Coating layer forming means for forming a coating layer on the surface of the recording medium by heating and pressurizing the recording medium and the coating sheet,
The coating layer forming means includes a pair of rollers, and at least one of the rollers includes a roller heating means that extends in the axial direction thereof, and the heating ability in the axial direction is adjusted.
To set the heating power distribution in the axial direction in the roller heating means,
Corresponding to the nip length in the circumferential direction of the pair of rollers in the pressurized state, the nip length is corresponding to the heating power distribution that can make the roller surface temperature in the axial direction in the non-pressed state uniform. A recording medium coating apparatus in which the longer the portion, the lower the heating ability. The recording medium having the coating layer formed on the surface thereof is further provided with coating layer reprocessing means for heating and pressurizing, and the applied pressure in the multi-layer forming means is higher than the applied pressure in the coating layer reprocessing means. Is set,
The coating layer reprocessing unit includes a pair of rollers, and at least one of the rollers includes a roller heating unit that extends in the axial direction and the heating ability in the axial direction is adjusted. In order to set the heating power distribution in the axial direction in the roller heating means, the pair in the pressurized state is compared with the heating power distribution that can make the roller surface temperature in the axial direction in the non-pressurized state uniform. Corresponding to the nip length in the circumferential direction of the roller forming, the longer the nip length, the lower the heating ability,
The recording medium coating apparatus according to claim 3, wherein the reduction rate of the multi-layer forming unit is set higher than the reduction rate of the coating layer reprocessing unit with respect to a heating rate reduction rate corresponding to the nip length.   The recording medium coating apparatus according to claim 1, wherein the roller is a hollow cylindrical roller, and the roller heating unit is provided inside the roller.   The recording medium coating apparatus according to claim 1, wherein the roller is a metal roller whose roller surface is coated with a rubber member, and the layer thickness of the rubber member is selected to be 1 to 2 mm. .

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