JP2014083791A - Coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating device including an inspection device capable of inspecting quality of coating after coating a material to be coated.SOLUTION: A coating device includes a coating part 6 for coating a material 5 to be coated with a varnish, and an inspection part 11 for inspecting the material 5 to be coated which is coated by the coating part 6. The inspection part 11 has a light source part 18 for irradiating a coated surface of the material 5 to be coated with black light, and an inspection device 20 for inspecting a coated part of the material 5 to be coated which is irradiated by the light source part 18 with the black light.

Description

  The present invention relates to a coating apparatus that coats a material to be coated such as a sheet or a web with a varnish.

  2. Description of the Related Art Conventionally, there is a coating apparatus (see, for example, Patent Document 1) that coats a material to be coated with varnish.

Special table 2004-516174 gazette

  In the coating apparatus of Patent Document 1 as described above, there is a problem that the quality of the coating applied to the sheet cannot be inspected.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a coating apparatus equipped with an inspection apparatus that can inspect the quality of the coating after coating the material to be coated. It is what we are going to propose.

  In order to achieve this object, the present invention includes a coating portion that coats a material to be coated with a varnish, and an inspection portion that inspects the material to be coated coated by the coating portion, and the inspection portion includes a coating material to be coated. A light source that irradiates the coating surface of the material with ultraviolet light, and an inspection device that inspects the coating portion on the coating surface of the material to be coated irradiated with ultraviolet light by the light source.

  In the present invention, the inspection section includes an inspection cylinder that conveys the material to be coated with the coating surface facing outward.

  Further, in the present invention, the inspection unit includes a drying unit that dries the coating surface by irradiating the material to be coated with light different from the ultraviolet light irradiated by the light source, and the light from the drying unit is the inspection device. And a light shielding plate for preventing entry into the inspection area.

  Furthermore, in the present invention, the coating unit includes an impression cylinder that holds and conveys the coating material, and a coater cylinder that contacts the impression cylinder and coats the coating material with varnish, and the light source and the inspection of the inspection unit The apparatus is directed to the impression cylinder and arranged to inspect the material to be coated on the downstream side in the conveying direction from the contact point between the impression cylinder and the coater cylinder.

  According to the present invention, by irradiating the coating surface of the material to be coated with ultraviolet light, the varnish component on the coating surface of the coating part reacts with ultraviolet light, and the quality of the coating is checked by inspecting the reaction state with an inspection device. Thus, it is possible to realize a coating apparatus including an inspection apparatus that can determine whether or not the coating of the sheet is correctly applied.

It is a side view which shows the whole structure of the coating inspection apparatus in 1st Embodiment based on this invention. It is a block diagram which shows the circuit structure of the varnish processing part in the 1st and 2nd embodiment which concerns on this invention. It is a side view which shows the whole structure of the coating test | inspection apparatus in 2nd Embodiment based on this invention.

  Embodiments of the present invention will be described below.

(1) 1st Embodiment As shown in FIG. 1, the coating apparatus 1 in 1st Embodiment is the supply as a sheet | seat supply part which supplies the sheet | seat 5 as a to-be-coated material one sheet at a time to the feeder board FB. The paper section 2 is generally composed of a varnish processing section 3 that coats the fed sheet 5 with varnish or the like, and a paper discharge section 4 as a sheet discharge section that discharges the coated sheet 5.

  In the sheet feeding unit 2, a soccer device (not shown) that sucks the sheets 5 one by one and feeds them to the feeder board FB in a state where a large number of sheets 5 on which a pattern is printed by another printing machine is stacked. Is provided. The feeder board FB conveys the sheet 5 from the sheet feeding unit 2 to the varnish processing unit 3.

  The varnish processing unit 3 includes a coating unit 6 as a coating unit that coats the sheet 5 with varnish, and a drying and inspection unit 11 as an inspection unit provided on the downstream side of the coating unit 6 in the sheet conveyance direction.

  The coating unit 6 includes a transfer cylinder 7 that receives a sheet 5 supplied from a feeder board FB via a swing device (not shown), an impression cylinder 8 that contacts the transfer cylinder 7 and receives the sheet 5 from the transfer cylinder 7, and the impression cylinder 8 is provided with a coater cylinder 9 disposed on the downstream side of the conveying cylinder 7 in contact with the transfer cylinder 7 in the sheet conveying direction, and a varnish supply cylinder 10 in contact with the coater cylinder 9. The transfer cylinder 7 and the impression cylinder 8 are provided with a holding claw device (not shown) for holding the sheet 5 in a held state.

  In the drying and inspection unit 11, the transfer cylinder 12 that contacts the impression cylinder 8 and receives the sheet 5 from the impression cylinder 8, and the transfer cylinder 12 on the downstream side in the sheet conveying direction from the contact portion of the transfer cylinder 12 with the impression cylinder 8. And a discharge cylinder 14 for receiving the sheet 5 conveyed by the inspection cylinder 13 on the downstream side in the sheet conveyance direction from the contact part of the inspection cylinder 13 with the transfer cylinder 12. The transfer cylinder 12 and the inspection cylinder 13 are also provided with a holding claw device (not shown) for holding the sheet 5 in a held state.

  Further, the drying and inspection unit 11 includes drying UV lights 15 and 16 as drying sections that irradiate light for drying (curing) the varnish transferred to the sheet 5, and the transfer cylinder 12 of the inspection cylinder 13. It is provided downstream of the contact portion in the sheet conveyance direction and upstream of the position where the sheet 5 is delivered to the discharge cylinder 14 in the sheet conveyance direction and directed toward the circumferential surface of the inspection cylinder 13.

  Further, the drying and inspection unit 11 is provided with a black light 18 as a UV light for inspection which is a light source for irradiating ultraviolet light for inspecting whether or not the coating of the sheet 5 is correctly applied. , 16 on the downstream side in the sheet conveyance direction, and on the upstream side in the sheet conveyance direction from the position where the sheet 5 is delivered to the discharge cylinder 14, and directed toward the peripheral surface of the inspection cylinder 13.

  Here, the drying UV lights 15 and 16 and the black light (inspection UV light) 18 both irradiate the same ultraviolet light, but the black light (inspection UV light) 18 can be directly seen by humans. In contrast, the UV light for drying 15 and 16 is ultraviolet light that is so bright that it cannot be seen directly by humans. Therefore, in the first embodiment, the drying UV lights 15 and 16 and the black light (inspection UV light) 18 are adjacent to each other. The light from the drying UV lights 15 and 16 is superior to the light, and the inspection by the black light (inspection UV light) 18 is not possible, and the inspection camera 20 may be damaged.

  Accordingly, the drying and inspection unit 11 has light from the drying UV lights 15 and 16 around the inspection cylinder 13 and between the drying UV lights 15 and 16 and the black light (inspection UV light) 18. However, a light shielding plate 17 is provided for preventing the ultraviolet light from the black light (inspection UV light) 18 and the inspection camera 20 from entering the inspection area.

  In the drying and inspection unit 11, an inspection camera 20 as an inspection device is attached to the tip of a camera mount 19 A provided above the frame 19 so as to be directed to the inspection cylinder 13. The inspection camera 20 is for photographing reflected light when the ultraviolet light from the black light (inspection UV light) 18 is irradiated onto the varnish coating surface of the sheet 5 being conveyed by the inspection cylinder 13, An image of the photographing result is output to a control unit (described later) having a microcomputer configuration.

  The paper discharge unit 4 includes a pair of left and right discharge chains between a sprocket (not shown) coaxial with the discharge cylinder 14 of the drying and inspection unit 11 and a sprocket 21 provided at the end of the paper discharge unit 4. The paper discharge chain 22 is stretched. The paper discharge chain 22 is provided with a plurality of claw hooks (not shown) for receiving the sheet 5 from the inspection cylinder 13 at regular intervals.

  The paper discharge unit 4 is provided with a non-defective product discharge device 23 for discharging the sheet 5 coated with varnish normally below the discharge chain 22, and the varnish is normally adjacent to the good product discharge device 23. A defective product discharging device 24 for discharging the uncoated defective sheet 5 is provided. The paper discharge unit 4 is provided with a discharge switching device (described later) that distributes the sheet 5 being conveyed into a non-defective product discharge device 23 and a defective product discharge device 24.

  In the coating apparatus 1 having such a configuration, the sheet 5 sucked by the soccer device (not shown) of the paper feeding unit 2 is sent to the feeder board FB, and the coating of the varnish processing unit 3 is performed via the feeder board FB. It is delivered to the transfer cylinder 7 in the unit 6.

  The sheet 5 is transferred from the transfer cylinder 7 of the coating unit 6 to the impression cylinder 8, and then conveyed while being wound around the circumferential surface of the impression cylinder 8, between the impression cylinder 8 and the coater cylinder 9. Pass through.

  At this time, since the varnish supplied from the varnish supply cylinder 10 is transferred to the peripheral surface of the coater cylinder 9, the sheet 5 conveyed by the impression cylinder 8 is brought into contact with the coater cylinder 9 and the impression cylinder 8. When passing through the surface, the sheet 5 is coated with a varnish through the coater cylinder 9, and the sheet 5 subjected to the varnish coating is conveyed to the drying and inspection unit 11.

  After the varnish-coated sheet 5 is transferred from the impression cylinder 8 to the drying cylinder 12 of the drying and inspection unit 11 and transferred from the transfer cylinder 12 to the inspection cylinder 13, the inspection cylinder 13 rotates. Be transported.

  At this time, the sheet 5 conveyed in a state of being wound around the peripheral surface of the inspection cylinder 13 is irradiated with light from the drying UV lights 15 and 16 on the varnish coating surface of the sheet 5. The varnish applied to is dried.

  Thereafter, the inspection cylinder 13 irradiates the coating surface of the sheet 5 being conveyed with the ultraviolet light from the black light (inspection UV light) 18 and the ultraviolet light from the black light (inspection UV light) 18. The irradiated varnish coating surface of the sheet 5 is photographed by the inspection camera 20, and an image of the photographing result is output to the control unit 200 having a microcomputer configuration of the varnish processing unit 3 as shown in FIG. 2. The control unit 200 of the varnish processing unit 3 determines the quality of the coating state of the sheet 5 based on the image of the photographing result by the inspection camera 20, and the discharge switching device 201 removes the sheet 5 by the discharge switching device 201 according to the determination result. And the defective product discharge device 24.

  At this time, since the light shielding plate 17 is provided between the drying UV lights 15 and 16 and the black light (inspection UV light) 18 around the inspection cylinder 13, the drying UV lights 15 and 16 are provided. The image of the varnish coating surface of the sheet 5 is taken by the inspection camera 20 in a state where the light from the camera does not enter the inspection area of the inspection camera 20 and is not affected by the drying UV lights 15 and 16. Become.

  By the way, when the ultraviolet light from the black light (inspection UV light) 18 is irradiated on the varnish coating surface of the sheet 5, the ultraviolet light reacts with the UV component (ultraviolet component) in the varnish, Among them, the coating portion where the varnish is sufficiently applied glows pale, while the portion where the other varnish is not sufficiently applied glows white.

  Therefore, if all of the varnish coating portion of the sheet 5 in the image photographed by the inspection camera 20 is shining blue, the control unit 200 determines that the varnish is uniformly applied to the varnish coating portion with an appropriate film thickness. . On the other hand, if the varnish coating surface in the image photographed by the inspection camera 20 is an interference fringe mixed with a pale coating portion and other white portions, the varnish is not properly applied to the varnish coating surface. The control unit 200 determines.

  The control unit 200 discharges the non-defective sheet 5 that is determined to have been normally coated with respect to the varnish-coated sheet 5 conveyed through the discharge chain 22 of the discharge unit 4 to the non-defective product discharge device 23. Then, the discharge switching device 201 is controlled so that the defective sheet 5 determined not to be coated normally is discharged to the defective product discharge device 24. That is, the control unit 200 distributes the sheets 5 to the non-defective product discharge device 23 or the defective product discharge device 24 by controlling the discharge switching device 201 according to the quality of the varnish coating state.

  As described above, the coating apparatus 1 is provided with the light shielding plate 17 that blocks the light from the drying UV lights 15 and 16 from entering the inspection area of the inspection camera 20. The light does not affect the inspection by the black light (inspection UV light) 18 and the inspection camera 20, and the image of the varnish coating surface of the sheet 5 by the inspection camera 20 can be accurately obtained, and the accuracy of varnish coating determination can be improved. Can be improved.

  According to the above configuration, in the coating apparatus 1, immediately after coating the varnish on the sheet 5 in the coating unit 6, the varnish is dried while the sheet 5 is being conveyed by the inspection cylinder 13 in the drying and inspection unit 11, and the coating state Therefore, from the varnish coating to the drying and the inspection of the varnish coating state can be performed in a short time on the in-line.

(2) Second Embodiment As shown in FIG. 2 in which parts corresponding to those in FIG. 1 are assigned the same reference numerals, the coating apparatus 200 in the second embodiment uses a sheet 5 as a material to be coated as a feeder board FB. A sheet feeding unit 2 serving as a sheet feeding unit for feeding the sheets one by one, a varnish processing unit 103 for coating the fed sheet 5 with varnish and the like, and a sheet discharging unit for discharging the coated sheet 5 The paper discharge unit 4 is generally configured.

  In the sheet feeding unit 2, a soccer device (not shown) that sucks the sheets 5 one by one and feeds them to the feeder board FB in a state where a large number of sheets 5 on which a pattern is printed by another printing machine is stacked. Is provided. The feeder board FB conveys the sheet 5 from the sheet feeding unit 2 to the varnish processing unit 103.

  The varnish processing unit 103 includes a coating and inspection unit 51 and a drying unit 52.

  The coating and inspection unit 51 of the varnish processing unit 103 receives the sheet 5 supplied from the feeder board FB via a swing device (not shown), receives the sheet 5 from the transfer cylinder 7 in contact with the transfer cylinder 7. An impression cylinder 50, a coater cylinder 9 that is in contact with the impression cylinder 50 and disposed downstream of the contact area of the impression cylinder 50 with the transfer cylinder 7, and a varnish supply cylinder 10 that is in contact with the coater cylinder 9. A discharge cylinder 14 is provided for receiving the sheet 5 conveyed by the impression cylinder 50 on the downstream side in the sheet conveyance direction from the contact portion between the impression cylinder 50 and the coater cylinder 9. The transfer cylinder 7 and the impression cylinder 50 are provided with a gripping claw device (not shown) for holding the sheet 5 in a state where the sheet 5 is held. Incidentally, the impression cylinder 50, the coater cylinder 9 and the varnish supply cylinder 10 constitute a coating portion.

  Further, the impression cylinder 50 is provided with a black light (inspection UV light) 18 as a light source for irradiating ultraviolet light for inspecting whether or not the coating of the sheet 5 is normally applied to the coater cylinder 9. It is provided on the downstream side in the sheet conveying direction from the contact portion and on the upstream side in the sheet conveying direction from the position where the sheet 5 is delivered to the discharge cylinder 14, and directed toward the circumferential surface of the impression cylinder 50.

  Further, the coating and inspection unit 51 includes an impression cylinder 50, and ultraviolet light from the black light (inspection UV light) 18 is applied between the black light (inspection UV light) 18 and the coater cylinder 9. A light shielding plate 30 is provided for preventing entry into the varnish portion on the surface of the cylinder 9 and the varnish supply cylinder 10.

  In the drying unit 52, an inspection camera 20 as an inspection device is attached to the tip of a camera installation table 19 </ b> A provided above the frame 19 so as to be directed to the impression cylinder 50. The inspection camera 20 is for photographing reflected light when the ultraviolet light from the black light (inspection UV light) 18 is irradiated onto the varnish coating surface of the sheet 5 being conveyed by the impression cylinder 50, An image of the photographing result is output to a control unit (described later). Incidentally, the black light 18 and the inspection camera 20 constitute an inspection unit.

  The impression cylinder 50 in this case has a role of coating the varnish via the coater cylinder 9 and also serves as an inspection cylinder for inspecting the quality of the varnish coating state on the sheet 5 being conveyed by the impression cylinder 50. Have.

  The paper discharge unit 4 includes a pair of left and right discharge chains between a sprocket (not shown) coaxial with the discharge drum 14 of the drying unit 52 and a sprocket 21 provided at the end of the paper discharge unit 4. A paper discharge chain 22 is stretched. The paper discharge chain 22 is provided with a plurality of claw hooks (not shown) for receiving the sheet 5 from the impression cylinder 50 at regular intervals.

  The drying unit 52 is provided with a UV light unit 53 as a drying unit that is a set of a plurality of drying UV lights on the inner peripheral side of the paper discharge chain 22 of the paper discharge unit 4.

  The paper discharge unit 4 is provided with a non-defective product discharge device 23 for discharging the sheet 5 coated with varnish normally below the discharge chain 22, and the varnish is normally adjacent to the good product discharge device 23. A defective product discharging device 24 for discharging the uncoated defective sheet 5 is provided. The paper discharge unit 4 is provided with a discharge switching device (described later) that distributes the sheet 5 being conveyed into a non-defective product discharge device 23 and a defective product discharge device 24.

  In the coating apparatus 100 having such a configuration, the sheet 5 sucked by the soccer device (not shown) of the paper feeding unit 2 is sent to the feeder board FB, and the coating of the varnish processing unit 103 is performed via the feeder board FB. And it is delivered to the transfer cylinder 7 in the inspection unit 51.

  The sheet 5 is transferred from the transfer cylinder 7 to the impression cylinder 50 and then passes between the impression cylinder 50 and the coater cylinder 9.

  At this time, since the varnish supplied from the varnish supply cylinder 10 is transferred to the peripheral surface of the coater cylinder 9, the sheet 5 conveyed by the impression cylinder 50 is brought into contact with the coater cylinder 9 and the impression cylinder 50. When passing through the surface, the sheet 5 is coated with a varnish through the coater cylinder 9, and the sheet 5 with the varnish coating is conveyed by the impression cylinder 50.

  In other words, the coating portion constituted by the impression cylinder 50, the coater cylinder 9 and the varnish supply cylinder 10 is located upstream of the black light (inspection UV light) 18 as a light source and the inspection camera 20 as an inspection apparatus in the sheet conveying direction. Varnish is coated on the sheet 5 which is disposed and conveyed by an impression cylinder 50 which serves as an inspection cylinder.

  Then, immediately after the varnish coating on the sheet 5, the pressure drum 50 irradiates the varnish coating surface of the sheet 5 being conveyed with the ultraviolet light from the black light 18, and as shown in FIG. (Inspection UV light) The varnish coating surface of the sheet 5 irradiated with ultraviolet light from 18 is photographed by the inspection camera 20, and an image of the photographing result is output to the control unit 200 having a microcomputer configuration of the varnish processing unit 103. Is done. The control unit 200 of the varnish processing unit 103 determines the coating state of the sheet 5 based on the image of the photographing result obtained by the inspection camera 20, and the sheet switching unit 201 removes the sheet 5 from the non-defective product discharge device 23 according to the determination result. Sorted to non-defective product discharge device 24.

  At this time, since the light blocking plate 30 for blocking between the coater cylinder 9, the varnish supply cylinder 10 and the black light (inspection UV light) 18 is provided around the impression cylinder 50, the black light (Inspection UV light) 18 by the inspection camera 20 while preventing the adverse effect that the varnish before the transfer on the surface of the coater cylinder 9 and the varnish supply cylinder 10 is irradiated with ultraviolet light from the coating cylinder 9 and the varnish supply cylinder 10 is cured. An image of the varnish coating surface of the sheet 5 can be obtained accurately.

  Therefore, if all of the varnish coating portion of the sheet 5 in the image photographed by the inspection camera 20 is shining blue, the control unit 200 determines that the varnish is uniformly applied to the varnish coating portion with an appropriate film thickness. . On the other hand, if the varnish coating surface in the image photographed by the inspection camera 20 is an interference fringe in which a pale coating portion and a white portion are mixed, the varnish is not properly applied to the varnish coating surface. 200 determines.

  Thereafter, while the varnish-coated sheet 5 is being conveyed by the paper discharge chain 22 via the paper discharge chain 22 of the paper discharge unit 4, the light from the UV light unit 53 of the drying unit 52 is irradiated with the varnish of the sheet 5. Since the coating surface is irradiated, the varnish applied to the sheet 5 is dried.

  The control unit 200 discharges the non-defective sheet 5 that is determined to have been normally coated with respect to the varnish-coated sheet 5 conveyed through the discharge chain 22 of the discharge unit 4 to the non-defective product discharge device 23. Then, the discharge switching device 201 is controlled so that the defective sheet 5 determined not to be coated normally is discharged to the defective product discharge device 24. That is, the control unit 200 distributes the sheets 5 to the non-defective product discharge device 23 or the defective product discharge device 24 by controlling the discharge switching device 201 according to the quality of the varnish coating state.

  According to the above configuration, in the coating apparatus 100, immediately after coating the sheet 5 via the impression cylinder 50 in the coating and inspection unit 51, the coating state is being transferred while the sheet 5 is being conveyed via the same impression cylinder 50. Therefore, from the varnish coating to the inspection of the varnish coating state can be executed on the in-line in a minimum time.

(3) Other Embodiments In the first and second embodiments described above, the sheet 5 determined to be normally coated in the paper discharge unit 4 is discharged to the non-defective product discharge device 23. The defective sheet 5 determined not to be normally coated with the varnish was distributed by being discharged to the defective product discharge device 24. However, the present invention is not limited to this, and only one discharge device is used to print a mark indicating that the defective sheet 5 is defective in coating, or between the defective sheet 5 and the non-defective sheet 5. The non-defective sheet 5 and the defective sheet 5 may be sorted by inserting a tape.

  In the first and second embodiments described above, the coater cylinder 9 is in contact with the impression cylinder 8 (FIG. 1), and the coater cylinder 9 is in contact with the impression cylinder 50 (FIG. 3). As described above, the present invention is not limited to this, and the coater cylinder 9 can freely rotate on the frame 19 of the coating unit 6 (FIG. 1) or the coating and inspection unit 51 (FIG. 3) via an eccentric bearing (not shown). The coater cylinder 9 may be detachable from the impression cylinders 8 and 50 by utilizing the eccentric action of the eccentric bearing. In this case, the coating process can be performed when the coater cylinder 9 reaches the impression cylinders 8 and 50, and the coating process can be stopped when the coater cylinder 9 leaves the impression cylinders 8 and 50.

  Thereby, immediately after coating the varnish on the sheet 5 in the coating unit 6, the quality of the varnish coating state is determined following the drying process of the varnish on the in-line during the transport of the sheet 5 by the inspection cylinder 13 in the drying and inspection unit 11. Therefore, if the coating process by the coating unit 6 is stopped when the coating defect is detected, the generation of damaged paper on the sheet 5 that causes the coating defect can be minimized.

  Similarly, immediately after coating the varnish on the sheet 5 via the impression cylinder 50 in the coating and inspection unit 51, it is possible to determine whether the varnish coating state is good or not during the conveyance of the sheet 5 by the same impression cylinder 50 to which the coating is applied. Therefore, if the coating process by the coating and inspection unit 51 is stopped at the time when the coating defect is detected, it is possible to minimize the occurrence of paper loss of the sheet 5 that causes the coating defect.

  Furthermore, in the above-described embodiment, the case where the sheet 5 is targeted as the material to be coated has been described. However, the present invention is not limited to this, and the web may be targeted.

  Furthermore, in the above-described embodiment, the case where the UV light for drying is used has been described. However, the present invention is not limited to this, and is not necessarily ultraviolet light for drying, but other infrared light or the like. Light may be used.

  DESCRIPTION OF SYMBOLS 1,100 ... Coating apparatus, 2 ... Paper feed part, 3,103 ... Varnish processing part, 4 ... Paper discharge part, 5 ... Sheet, 6 ... Coating unit (coating part), 7, 12 ... Transfer cylinder, 8 ... Pressure Cylinder, 9 ... Coater cylinder, 10 ... Varnish supply cylinder, 11 ... Drying and inspection unit (inspection part), 13 ... Inspection cylinder, 14 ... Discharge cylinder, 15, 16 ... UV light for drying (drying part), 17, 30 ... Light shielding plate, 18 ... Black light (light source), 19 ... Frame, 19A ... Camera mounting table, 20 ... Inspection camera (inspection device), 21 ... Sprocket, 22 ... Discharge chain, 23 ... Non-defective product discharge device, 24 ... No Non-defective product discharge device, 50 ... impression cylinder (inspection cylinder), 53 ... UV light unit (drying unit).

Claims (4)

A coating part for coating the material to be coated with varnish;
An inspection unit for inspecting the material to be coated coated by the coating unit,
The inspection unit
A light source for irradiating the coating surface of the material to be coated with ultraviolet light;
An inspection apparatus for inspecting a coating portion on a coating surface of a coating material irradiated with ultraviolet light from the light source. The coating apparatus according to claim 1, wherein the inspection unit includes an inspection cylinder that conveys the material to be coated with the coating surface facing outward. The inspection unit is a drying unit that dries the coating surface by irradiating the material to be coated with light different from the ultraviolet light irradiated by the light source,
The coating apparatus according to claim 2, further comprising: a light shielding plate that prevents light from the drying unit from entering the inspection area of the inspection apparatus. The coating unit includes an impression cylinder that holds and conveys the material to be coated, and a coater cylinder that contacts the impression cylinder and coats the material to be coated with varnish.
The light source and the inspection device of the inspection unit are arranged so as to be directed to the impression cylinder and to inspect the material to be coated on the downstream side in the transport direction from the contact point between the impression cylinder and the coater cylinder. The coating apparatus according to claim 1.

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