JP2020040353A - Printing device - Google Patents

Abstract

To provide a printing device that can prevent falling-off and bleeding of ink by performing printing and drying in parallel without contacting of a guide roller with a printing surface, so as to be able to form clear characters and images.SOLUTION: A printing device 1 comprises: a columnar drum 10 that has a rotating shaft Oand rotates counter-clockwise with respect to the rotating shaft Owhile supporting a rear surface 100a of a lengthy matter 100 to be printed; four inkjet heads 20a-20d, arranged to oppose to a front surface 100b of the lengthy matter 100 to be printed arranged on the drum 10, which perform printing by applying four kinds of ink respectively onto the front surface 100b of the lengthy matter 100 to be printed; and four drying parts 30a-30d, arranged at respective downstream sides of the four inkjet heads 20a-20d with respect to a rotating direction of the drum 10, which dry the front surface 100b of the lengthy matter 100 to be printed.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inkjet printing apparatus, and more particularly, to an inkjet printing apparatus that performs printing and drying in parallel.

  Conventionally, a plurality of inkjet type printing apparatuses have been proposed. For example, Patent Document 1 discloses a printing method capable of suppressing the occurrence of printing defects by dropping ink on a printing object in a state in which wrinkles or expansion and contraction do not occur in the belt-shaped printing object being conveyed. An apparatus is described.

  The printing apparatus described in Patent Literature 1 includes a paper feeding unit that feeds a long strip-shaped print material, an inkjet coating unit that applies ink to the long print material sent from the paper feed unit, and an inkjet coating device. And a winding section for winding a long printing material to which ink has been applied by the section. The ink jet application section includes a heating roller on which a long printing material is stretched, and an ink jet head for dropping ink on a portion of the long printing material stretched by the heating roller.

  Further, the printing apparatus described in Patent Document 1 guides a long printing material between adjacent heating rollers and a long printing material sent out from the heating roller in the ink jet application unit. A plurality of guide rollers are provided for changing the direction of a long printing material by these guide rollers, and drying is performed by a heating roller provided side by side.

JP-A-2015-63027

  However, in the printing apparatus described in Patent Literature 1, a guide roller is disposed immediately downstream of the ink jet application unit for each color, and the guide roller rotates so as to come into contact with the printing surface of the printing material. Due to being pressed against the guide roller, there is a problem that the printed characters and images are blurred because they fall off from the printing surface or spread over a substantial area of the printing substrate.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and printing and drying are performed in parallel without contact of a guide roller with a printing surface, thereby preventing dropout and bleeding of ink, and achieving clear printing. An object of the present invention is to provide a printing apparatus capable of forming various characters and images.

  To achieve the above object, the present invention is configured as follows.

  (1) A printing apparatus according to the present invention has a rotating shaft, and a rotating support that rotates in a predetermined direction with respect to the rotating shaft while supporting the back surface of a long printing medium; A plurality of ink-jet heads arranged to face the surface of the long printing medium arranged in the plurality of ink jet heads for performing printing by applying each of a plurality of inks on the surface of the long printing medium, And a plurality of drying units disposed downstream of each of the plurality of inkjet heads with respect to a rotation direction of the rotating support, and configured to dry a surface of the long printing substrate.

  According to the configuration, the ink applied to the surface of the long printing material by the inkjet head is dried by the drying unit disposed on the downstream side of the inkjet head, so that the printing material is printed on the surface of the printing material. Printing and drying can be performed in parallel without the belt that moves the paper or the guide roller that guides the belt directly contacting the printing surface, preventing the ink from falling off or bleeding, and forming clear characters and images. can do.

  (2) The printing apparatus of the present invention preferably further includes a heating unit that heats the back surface of the long printing medium disposed on the rotating support. According to this structure, the printing material can be effectively heated from the back side by the heating unit, and thus the moisture contained in the ink applied to the printing material can be evaporated and effectively dried.

  (3) Preferably, the printing apparatus of the present invention further includes a suction unit for suctioning the long printing material on the rotating support. According to this configuration, it is possible to prevent the printing medium from floating from the surface of the rotating support.

  (4) In the printing apparatus according to the aspect of the invention, preferably, the rotating support is a cylindrical drum that rotates in a predetermined direction with respect to the rotation axis while supporting a back surface of the long printing material. . According to this structure, the printing material can be prevented from floating from the surface of the belt by making the printing material follow the surface of the drum.

  (5) In the printing apparatus according to the aspect of the invention, preferably, the heating unit is configured to cause the drum to generate heat, and the heated drum heats the back surface of the long printing material. According to this structure, the heat of the heated drum can be directly transmitted to the back surface of the printing material, so that the printing material can be dried more effectively.

  (6) In the printing apparatus according to the aspect of the invention, preferably, the heating unit includes a drum heating unit configured to heat the drum, the drum heating unit being disposed inside the drum, and the elongate unit being heated via the drum. The back side of the substrate to be printed is heated. According to this structure, the heat can be easily transmitted to the back surface of the printing material via the drum by the drum heating means, so that the printing material can be effectively dried.

  (7) In the printing apparatus according to the aspect of the invention, preferably, the rotation support has rotation axes that are parallel to each other, and a predetermined direction with respect to the rotation axis while supporting the back surface of the long printing medium. And a plurality of columnar support rollers that rotate in a row, and the long printing medium is disposed so as to be bridged between the plurality of support rollers. According to this structure, the tension can be imparted to the printing object by spanning the long printing object between the plurality of support rollers. Therefore, the ink by the inkjet head can be uniformly applied to the printing object. Can be.

  (8) In the printing apparatus according to the aspect of the invention, preferably, the heating unit is disposed between each of the plurality of support rollers, and the heating unit is configured to extend between the plurality of support rollers. Heat the back. According to this structure, since the heat generated by the heating unit is transmitted to the back surface of the printing medium, the printing medium can be efficiently heated and dried.

  According to the aspect of the invention, by performing printing and drying in parallel without the guide roller touching the printing surface, it is possible to prevent the ink from dropping or bleeding, and to form clear characters and images. A printing device can be provided.

FIG. 1 is a schematic configuration diagram illustrating a printing apparatus according to a first embodiment of the present invention. FIG. 2 is a diagram for describing a suction unit of the printing apparatus according to the first embodiment. FIG. 2 is a sectional view illustrating a drying unit of the printing apparatus according to the first embodiment. FIG. 6 is a schematic configuration diagram illustrating a printing apparatus according to a second embodiment of the present invention. FIG. 11 is a schematic configuration diagram illustrating a printing apparatus according to a third embodiment of the present invention. FIG. 6 is a diagram of the induction heating unit illustrated in FIG. 5 as viewed from a back surface side of a printing medium. FIG. 11 is a schematic configuration diagram illustrating a printing apparatus according to a fourth embodiment of the present invention.

  Hereinafter, an embodiment of a printing apparatus according to the present invention will be described with reference to the accompanying drawings. These figures are schematic views, and do not necessarily show the sizes in exact proportions. In the drawings, the same components are denoted by the same reference numerals. Further, the upstream side in the flow direction of the printing medium may be simply referred to as “upstream side”, and the downstream side in the flow direction of the printing medium may be simply referred to as “downstream side”.

[First Embodiment]
The printing apparatus 1 according to the first embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 and 2, the printing apparatus 1 includes a cylindrical drum 10 as a rotary support that conveys and supports a back surface 100 a of a long print substrate 100, and a cylindrical support roller 12. , A cylindrical support roller 14.

  Further, the printing apparatus 1 dries the four ink jet heads 20 a, 20 b, 20 c and 20 d which apply and print each of the four types of inks on the surface 100 b of the printing material 100 and the surface 100 b of the printing material 100. The four drying units 30 a, 30 b, 30 c and 30 d, a heating unit (not shown) for heating the back surface 100 a of the printing material 100 adsorbed on the drum 10, and the printing material 100 adsorbed on the drum 10 And a suction unit (not shown) for preventing the print substrate 100 from floating.

The cylindrical drum 10 is disposed between the support roller 12 and the support roller 14 in the transport direction of the printing medium 100. The drum 10 conveys the printing medium 100 by driving the rotation with respect to the rotation axis O ₁ in the counterclockwise direction by a power unit such as a motor (not shown).

The support roller 12 is disposed upstream and below the drum 10. The support roller 12, by rotating in the clockwise direction with respect to the rotation axis O ₂ in accordance with rotation of the drum 10 to be conveyed while supporting the surface 100b of the substrate 100.

The support roller 14 is disposed downstream and below the drum 10. The support roller 14, the drum 10 and the supporting roller 12 with the to rotate, while supporting the back surface 100a of the substrate 100, to rotate relative to the rotation axis O ₃ in the counterclockwise direction.

The printing medium 100 is stretched in a state of being in contact with the support roller 12, the drum 10, and the support roller 14 described above. Then, the printing medium 100 is conveyed from the support roller 12 to the support roller 14 via the drum 10 in a state where tension is applied. Rotation axis _{O 1} of the drum 10, the rotation axis _{O 3} of the rotary shaft _{O 2} and the supporting roller 14 of the support rollers 12 are respectively parallel.

The four ink-jet heads 20a to 20d are arranged opposite to and spaced apart from the surface 100b of the printing medium 100 adsorbed on the drum 10, respectively. The four ink-jet heads 20a~20d each other, respectively, are arranged at equal angular intervals with respect to the rotation axis _{O 1} of the drum 10. The four inkjet heads 20a to 20d perform printing by applying four types of different inks to the surface 100b of the print substrate 100. These four types of ink are composed of black (K), cyan (C), magenta (M), and yellow (Y).

The four drying units 30a to 30d are arranged to face and separate from the surface 100b of the printing medium 100 adsorbed to the drum 10, and are arranged downstream of the four inkjet heads 20a to 20d. I have. For example, the drying unit 30a is disposed adjacent to the downstream side of the inkjet head 20a, and dries the ink applied by the inkjet head 20a. Note that the drying units 30b to 30d have the same configuration. Also, among the four drying section 30a~30d are respectively arranged at equiangular intervals with respect to the rotation axis _{O 1} of the drum 10.

  As shown in FIG. 3, each of the four drying units 30 a to 30 d is formed by a hot air injection nozzle 32 having an outer tubular body 34 and an inner tubular body 36 disposed inside the outer tubular body 34. It is configured. Hot air for heating the surface 100b of the substrate 100 from the source of hot air (not shown) through the inner tubular body 36 to the surface 100b of the substrate 100, as shown by the dashed arrow in FIG. The water contained in the sprayed and applied ink is evaporated to promote fixing of the ink.

  On the other hand, the warm air blown to the surface 100b of the printing medium 100 is exhausted from an exhaust passage 38 formed between the outer tubular main body 34 and the inner tubular main body 36. The exhaust passage 38 is in fluid communication with a decompression pump (not shown), and the warm air is sucked from the exhaust passage 38 and exhausted to the outside.

  As shown in FIG. 2, the suction unit (not shown) guides the air decompressed by the vacuum pump to the suction holes by providing a plurality of suction holes on the surface 10 b of the drum 10, A suction force S for vacuum-sucking the print substrate 100 is generated. Thereby, it is possible to suppress the printing medium 100 from being displaced from the drum 10. Specifically, it is possible to suppress the printing medium 100 from shifting in the vertical direction, the transport direction, and the width direction with respect to the surface 10b of the drum 10. Thereby, the ink can be applied to a predetermined position of the print substrate 100.

  In the heating unit (not shown), pressurized steam supply means as drum heating means for heating the drum 10 is arranged inside the drum 10. The heating unit (pressurized steam supply means) heats the entire drum 10 by supplying pressurized steam from a predetermined position (location) of the drum 10 to the internal space, and the back surface of the printing material 100. Heat is transmitted to 100a.

  According to the first embodiment described above, the following effects (1) to (4) can be obtained.

  (1) In the printing apparatus 1 according to the first embodiment, each of the four inkjet heads 20a to 20d is arranged so as to face the front surface 100b of the long print medium 100 arranged on the drum 10, and Printing is performed by applying each of the four types of ink on the surface 100b of the long printing substrate 100. Further, each of the four drying units 30a to 30d is arranged on the downstream side of each of the four inkjet heads 20a to 20d with respect to the rotation direction of the drum 10, and the surface 100b of the long printing material 100 is dried. . Thus, printing and drying can be performed in parallel without the belt for moving the printing material 100 and the guide roller for guiding the belt on the surface 100b of the printing material 100 directly contacting the printing surface. Therefore, clear characters and images can be formed by preventing the ink from falling off or bleeding.

  (2) In the printing apparatus 1 according to the first embodiment, a drum heating unit (pressurized steam supply unit) that heats the drum 10 is provided inside the drum 10, and is also connected to the drum 10 via the heated drum 10. By heating the back surface 100a of the long printing material 100, heat can be easily transmitted to the back surface 100a of the printing material 100 via the drum by the drum heating means, so that the printing material 100 is effectively dried. be able to.

  (3) In the printing apparatus 1 according to the first embodiment, since the suction unit suctions the long printing material 100 onto the drum 10, the printing material 100 can be prevented from floating from the surface 10 b of the drum 10. Thus, the heating efficiency of the printing medium 100 by the heating unit can be improved, and the surface 100b of the printing medium 100 can be prevented from coming into contact with the four inkjet heads 20a to 20d.

(4) In the printing apparatus 1 according to the first embodiment, by rotating with respect to the rotation axis O ₁ in the counterclockwise direction while supporting the cylindrical drum 10 is elongated rear surface 100a of the substrate 100 By arranging the substrate 100 along the surface 10b of the drum 10, the substrate 100 can be prevented from floating from the surface 10b of the drum 10. For this reason, the heating efficiency of the printing medium 100 by the heating unit can be increased, and the surface 100b of the printing medium 100 can be prevented from coming into contact with the four inkjet heads 20a to 20d.

[Second embodiment]
Next, a printing apparatus 2 according to a second embodiment of the present invention will be described with reference to FIG. In the printing apparatus 2, unlike the printing apparatus 1 according to the first embodiment, an example will be described in which an endless belt 60 is disposed between the drum 10 and the printing medium 100. In the second embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Only different parts will be described in detail.

  In the printing apparatus 2, as shown in FIG. 4, an endless belt 60 is stretched between the drum 10 and the support roller 14, and the back surface 60a of the endless belt 60 is adsorbed on the front surface 10b of the drum 10. The back surface 100a of the printing medium 100 is arranged on the front surface 60b of the endless belt 60 in contact therewith. The printing medium 100 is conveyed with the rotation of the support roller 12 in the clockwise direction and the rotation of the drum 10 and the support roller 14 in the counterclockwise direction. In addition, the endless belt 60 may be an adsorption belt that adsorbs to the drum 10 and the print substrate 100. The other configuration of the second embodiment is the same as the configuration of the above-described first embodiment.

  According to the second embodiment described above, the following effect (5) can be obtained in addition to the effects (1) to (4) of the first embodiment.

  (5) In the printing apparatus 2 according to the second embodiment, when the endless belt 60 made of a non-slip material such as rubber is disposed on the surface 10b of the metal drum 10, the printing medium 100 is transported while being transported. Since the slipping can be suppressed, the ink can be applied to a predetermined position on the surface 100b of the printing substrate 100. The materials of the drum 10 and the endless belt 60 are not particularly limited, and may be appropriately selected in accordance with the material of the printing substrate 100.

[Third Embodiment]
Next, a printing apparatus 3 according to a third embodiment of the present invention will be described with reference to FIGS. In the printing apparatus 3, unlike the first embodiment in which the cylindrical drum 10 is applied as a rotating support that rotates while supporting the back surface 100 a of the printing medium 100, five cylindrical supports are used as the rotating support. An example in which the rollers 70a to 70e are applied will be described. In the third embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Only different parts will be described in detail.

  As shown in FIG. 5, the printing apparatus 3 includes five cylindrical support rollers 70a, 70b, 70c, 70d, and 70e as rotary supports that convey while supporting the back surface 100a of the long print substrate 100. A cylindrical feed roller 16 for feeding the printing material 100 to the support rollers 70a to 70e, and a cylindrical drawing roller 18 for pulling the printing material 100 from the drum 10.

  The printing medium 100 is stretched in a state of being in contact with the delivery roller 16, the support rollers 70a to 70e, and the extraction roller 18. The printing medium 100 is conveyed from the delivery roller 16 to the pull-out roller 18 via the support rollers 70a to 70e in a state where tension is applied.

  The support rollers 70a to 70e are arranged at predetermined intervals. The rotating shaft 72a of the supporting roller 70a, the rotating shaft 72b of the supporting roller 70b, the rotating shaft 72c of the supporting roller 70c, the rotating shaft 72d of the supporting roller 70d, and the rotating shaft 72e of the supporting roller 70e are parallel to each other. The rotation shaft 72c of the support roller 70c is disposed above the rotation shaft 72b of the support roller 70b and the rotation shaft 72d of the support roller 70d, and the rotation shaft 72b of the support roller 70b and the rotation shaft 72d of the support roller 70d are , The rotation axis 72a of the support roller 70a and the rotation axis 72e of the support roller 70e.

The delivery roller 16 is disposed near the upstream side of the support roller 70a. The delivery roller 16 is conveyed by rotating in the clockwise direction with respect to the rotation axis O ₄ by the power device such as a motor (not shown), with respect to the support roller 70a while supporting the surface 100b of the substrate 100 I do.

The pull-out roller 18 is arranged near the downstream side of the support roller 70e. The pull-out roller 18, with the delivery roller 16 and the supporting roller 70a~70e from rotating, while supporting the back surface 100a of the substrate 100, to rotate relative to the rotation axis _{O 5} in the counterclockwise direction.

  Further, the printing apparatus 3 dries the four ink jet heads 20 a, 20 b, 20 c and 20 d that apply and print each of the four types of inks on the surface 100 b of the substrate 100 and the surface 100 b of the substrate 100. The printing apparatus includes four drying units 30a, 30b, 30c, and 30d, and four induction heating units 80a, 80b, 80c, and 80d that heat the back surface 100a of the printing medium 100.

  The four inkjet heads 20 a to 20 d are arranged to face the surface 100 b of the print substrate 100. These four inkjet heads 20a to 20d perform printing by applying four different types of inks to the surface 100b of the printing substrate 100. These four types of ink are composed of black (K), cyan (C), magenta (M), and yellow (Y).

  The four drying units 30a to 30d are arranged downstream of the four inkjet heads 20a to 20d, respectively. For example, the drying unit 30a is arranged adjacent to the downstream side of the inkjet head 20a, and dries the ink applied by the inkjet head 20a by the drying unit 30a. Other structures and functions of the drying units 30a to 30d are the same as those of the first embodiment.

  The four induction heating units 80a to 80d are arranged on the back surface 100a side of the printing material 100 as heating means for heating the back surface 100a of the printing material 100, respectively. The induction heating units 80a to 80d are arranged between the support rollers 70a to 70e, respectively. Specifically, the induction heating unit 80a is disposed between the support rollers 70a and 70b. The induction heating section 80b is arranged between the support rollers 70b and 70c. The induction heating section 80c is disposed between the support rollers 70c and 70d. The induction heating section 80d is arranged between the support rollers 70d and 70e.

  The induction heating units 80a to 80d are disposed near the back surface 100a of the printing medium 100 and extend in the transport direction of the printing medium 100, and have metal plates 82a, 82b, 82c and 82d, and these metal plates 82a to 82d. And an IH-type heater having coil portions 84a, 84b, 84c and 84d arranged so as to face. In these induction heating sections 80a to 80d, the high frequency power is supplied to the coil sections 84a to 84d by the high frequency power supply, so that the metal plates 82a to 82d facing each of the coil sections 84a to 84d are induction heated (heat generation). Therefore, the back surface 100a of the printing substrate 100 is heated.

  In addition, the inkjet heads 20a to 20d are arranged at the upstream ends of the induction heating units 80a to 80d so as to face each other with the printing medium 100 interposed therebetween. On the other hand, at the downstream end of each of the induction heating sections 80a to 80d, each of the drying sections 30a to 30d is arranged to face each other with the printing medium 100 interposed therebetween.

  As shown in FIG. 6, the metal plate 82a of the induction heating unit 80a has two metal pieces 821a and 822a divided in the width direction of the print substrate 100. The coil portion 84a of the induction heating portion 80a is arranged close to the back surfaces of the metal pieces 821a and 822a, and is electrically independent.

  As shown in FIG. 6A, when the width of the printing substrate 100 is larger than the width of the two metal pieces 821a and 822a, a high-frequency current is supplied to both the coil portions 841a and 842a, and the induction heating is performed. The metal pieces 821a and 822a heat the back surface 100a of the wide print substrate 100.

  As shown in FIG. 6B, when the width of the printing medium 100 is smaller than the width of the two metal pieces 821a or 822a, a high-frequency current is supplied only to the coil portion 842a, and the induction-heated metal piece 822a is supplied. Heats the back surface 100a of the print substrate 100 having a small width. By selecting the coil unit 841a or 842a that supplies the high-frequency current according to the width of the printing substrate 100 to be printed in this way, power consumption can be substantially suppressed. The configurations and functions of the metal plates 82b to 82d of the induction heating units 80b to 80d are the same as those of the metal plate 82a of the induction heating unit 80a.

  According to the third embodiment described above, in addition to the following effect (6) similar to the effect (1) of the first embodiment, the following effects (7) to (9) can be obtained. it can.

  (6) In the printing apparatus 3 according to the third embodiment, each of the four inkjet heads 20a to 20d is opposed to the surface 100b of the long print substrate 100 disposed on the five support rollers 70a to 70e. And printing is performed by applying each of the four types of inks onto the surface 100b of the long print substrate 100. Further, each of the four drying units 30a to 30d is arranged on the downstream side of each of the four inkjet heads 20a to 20d, and the surface 100b of the long printing medium 100 is dried. Thus, printing and drying can be performed in parallel without the belt for moving the printing material 100 and the guide roller for guiding the belt on the surface 100b of the printing material 100 directly contacting the printing surface. Therefore, clear characters and images can be formed by preventing the ink from falling off or bleeding.

  (7) In the printing apparatus 3 according to the third embodiment, the long printing medium 100 is disposed so as to be bridged between the five support rollers 70a to 70e. Since the tension can be applied to the printing medium 100 by being bridged between the five support rollers 70a to 70e, the ink from the inkjet heads 20a to 20d can be uniformly applied to the printing medium 100.

  (8) In the printing apparatus 3 according to the third embodiment, each of the induction heating units 80a to 80d arranged between the support rollers 70a to 70e is a long one that is bridged between the support rollers 70a to 70e. By heating the rear surface 100a of the substrate 100, the heat generated by the induction heating units 80a to 80d is transmitted to the rear surface 100a of the substrate 100, so that the substrate 100 is efficiently heated and dried. be able to.

  (9) In the printing apparatus 3 according to the third embodiment, the metal plate 82a of the induction heating unit 80a has two metal pieces 821a and 822a divided in the width direction of the print substrate 100, and Since the coil portion 84a has the two coil portions 841a and 842a arranged close to the back surface of each of the two metal pieces 821a and 822a, a high-frequency current can be supplied according to the width of the printing substrate 100 to be printed. Since the coil unit 841a or 842a to be supplied can be selected, power consumption can be substantially reduced.

[Fourth embodiment]
Next, a printing apparatus 4 according to a fourth embodiment of the present invention will be described with reference to FIG. In the printing apparatus 4, unlike the printing apparatus 3 according to the third embodiment, a metal material is provided between the printing medium 100 and the support rollers 70 a to 70 e and the coil sections 84 a to 84 d of the induction heating sections 180 a to 180 d. An example in which the endless belt 160 is disposed will be described. In the fourth embodiment, the same parts as those in the third embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Only different parts will be described in detail.

  In the printing apparatus 4, as shown in FIG. 7, a metal endless belt 160 is stretched between each of the five support rollers 70 a to 70 e, and the printing object 100 is placed on the surface 160 b of the endless belt 160. Are arranged in contact with each other. The printing medium 100 is moved from the upstream side along with the clockwise rotation of the delivery roller 16, the rotation of the support rollers 70a to 70e in the counterclockwise direction, and the rotation of the extraction roller 18 in the counterclockwise direction. It is transported downstream.

  Further, in the printing apparatus 4, the four induction heating sections 180a, 180b, 180c, and 180d respectively include four coil sections 84a to 84d extending along a region between each of the five support rollers 70a to 70e. And a high-frequency power source (not shown) for supplying a high-frequency current to the coil portions 84a to 84d. In this IH type heater, the high-frequency power supply supplies a high-frequency current to each of the coil portions 84a to 84d, so that the metal endless belt 160 facing each of the coil portions 84a to 84d is subjected to induction heating (heat generation). This heat can be directly transmitted to the back surface 100a of the printing substrate 100. The other configuration of the fourth embodiment is the same as the configuration of the above-described third embodiment.

  According to the above-described fourth embodiment, the following effects (10) and (11) can be obtained in addition to the effects (6) and (7) of the third embodiment.

  (10) In the printing apparatus 4 according to the fourth embodiment, the metal endless belt 160 that is heated by the induction heating units 80a to 80d disposed between the support rollers 70a to 70e is connected to the support rollers 70a to 70e. By heating the back surface 100a of the long printing material 100 bridged between the printing materials 70e, the heat of the metal endless belt 160 generated by each of the induction heating units 80a to 80d causes the back surface 100a of the printing material 100 to be heated. , And can be heated and dried more efficiently.

  (11) In the printing apparatus 4 according to the fourth embodiment, for example, when the support rollers 70a to 70e are formed of metal and the endless belt 160 is formed of a non-slip material such as rubber, the print target 100 is conveyed. Ink can be applied to a predetermined position on the front surface 100b of the printing substrate 100 because it can be prevented from slipping inside. The materials of the support rollers 70 a to 70 e and the endless belt 160 are not particularly limited, and may be appropriately selected according to the material of the printing material 100.

  The first to fourth embodiments may be modified as follows.

  In the first to fourth embodiments, an example in which four types of inks of different colors are applied as an example of the inkjet head, but the present invention is not limited to this. For example, in addition to four types of ink jet heads, one to three types, or five or more types can be applied. Further, in the above embodiment, four drying units are shown as an example of the drying unit, but the present invention is not limited to this. For example, in addition to four drying sections, one to three or five or more drying sections can be applied. It is preferable that the number of inkjet heads and the number of drying units are the same.

  In the third and fourth embodiments, five support rollers are shown as an example of the rotary support, but the present invention is not limited to this. For example, in addition to five support rollers, one to four or six or more support rollers can be applied.

  In the above-described first to fourth embodiments, as an example of the drying unit, an example in which the surface of the printing material is dried by injecting hot air from the hot air injection nozzle has been described, but the present invention is not limited to this. For example, a radiant heater that directly irradiates radiant heat, an optical dryer that irradiates infrared light or laser light, or an IH (induction heating) heater is also applicable.

  In the first embodiment, an example in which the entire drum is heated by supplying pressurized steam to the space inside the drum has been described as an example of the heating unit, but the present invention is not limited to this. For example, an IH type heater in which a coil portion is arranged near the outer periphery or inner periphery of a metal drum and a high frequency current is supplied to the coil portion to induce induction heating (heat generation) of the metal drum is applied. It is also possible. In this case, since the drum heated by the heating unit heats the back surface of the long printing material, the heat of the heated drum can be directly transmitted to the back surface of the printing material. Can be dried. Other configurations of the heating unit include a radiant heater that directly irradiates radiant heat, a configuration that injects hot air to heat the drum, an optical dryer that irradiates infrared light or laser light, or a fluid flow path inside the drum. May be formed to circulate or guide high-pressure steam, high-temperature water, high-temperature oil, and the like in the flow path.

  In the second and fourth embodiments, the endless belt is described as an example of the belt that conveys the print medium, but the present invention is not limited to this. For example, an endless belt that is provided with a supply unit that supplies the belt and a winding unit that winds the belt and that is bridged between them is also applicable.

  In the third embodiment, the example in which the metal plate of the induction heating unit is formed of two metal pieces has been described, but the present invention is not limited to this. For example, the configuration may be such that the metal plate of the induction heating unit is not divided, or may be divided into three or more metal pieces. Further, it is preferable to arrange the coil portions so as to correspond to the number of metal pieces.

  In the third and fourth embodiments, an example in which an IH type heater is applied as an example of the heating unit has been described, but the present invention is not limited to this. For example, if it is possible to heat the back surface of the printing material, a radiant heater that directly irradiates radiant heat, a configuration in which warm air is injected to heat the back surface of the printing material, or an optical device that irradiates infrared light or laser light The present invention can be applied to a type dryer, and these configurations may be appropriately combined.

  The suction unit described in the first and second embodiments for adsorbing the printed material to the rotating support can also be applied to the printing apparatuses of the third and fourth embodiments. In this case, in the printing apparatus according to the third embodiment, a plurality of suction holes may be provided in the support roller to generate a suction force, and in the printing apparatus according to the fourth embodiment, the suction roller may be endless. The suction belt may be provided with a plurality of suction holes to generate a suction force.

  In the first and second embodiments, an example is shown in which the four drying units are arranged at equal angular intervals with respect to the rotation axis of the drum, but the present invention is not limited to this. For example, in consideration of the type of ink used for printing and the time required for drying, the four drying units may be arranged at different angular intervals with respect to the rotation axis of the drum.

  -The above embodiments are all examples of the application of the present invention, and it is natural that any other embodiments within the scope of the claims are included in the technical scope of the invention.

1, 2, 3, 4 ... printing device 10 ... drum (rotary support)
20a, 20b, 20c, 20d ... inkjet heads 30a, 30b, 30c, 30d ... drying units 70a, 70b, 70c, 70d, 70e ... support rollers (rotary supports)
80a, 80b, 80c, 80d: induction heating unit 100: printed material 100a: back surface 100b: front surface 180a, 180b, 180c, 180d: induction heating unit

Claims (8)

A rotation support having a rotation axis and rotating in a predetermined direction with respect to the rotation axis while supporting the back surface of the long print substrate,
A plurality of ink droplets are arranged so as to face the surface of a long printing material arranged on the rotating support, and a plurality of inks are applied on the surface of the long printing material to perform printing. An inkjet head,
A printing apparatus, comprising: a plurality of drying units disposed downstream of each of the plurality of inkjet heads with respect to a rotation direction of the rotating support, for drying a surface of the long printing material.   The printing apparatus according to claim 1, further comprising: a heating unit configured to heat a back surface of the long printing medium disposed on the rotating support.   The printing apparatus according to claim 1, further comprising: a suction unit configured to suction the long printing material onto the rotating support.   4. The rotary support according to claim 1, wherein the rotary support is a cylindrical drum that rotates in a predetermined direction with respect to the rotation axis while supporting a back surface of the long print medium. 5. Printing equipment.   The printing apparatus according to claim 4, wherein the heating unit is configured to cause the drum to generate heat, and the heated drum heats a back surface of the long print medium.   5. The heating unit, wherein a drum heating unit that heats the drum is disposed inside the drum, and the heating unit heats the back surface of the long printing material via the heated drum. 6. A printing device according to claim 1. The rotating support has a plurality of rotating shafts parallel to each other, and is a plurality of columnar support rollers that rotate in a predetermined direction with respect to the rotating shaft while supporting the back surface of the long printing medium,
The printing apparatus according to any one of claims 1 to 3, wherein the long print medium is arranged so as to be bridged between the plurality of support rollers. The printing apparatus according to claim 7, wherein the heating unit is arranged between each of the plurality of support rollers, and heats a back surface of the long print medium bridged between the plurality of support rollers. .

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