JP7379991B2 - Heating device and printing device - Google Patents

Description

The present invention relates to a heating device and a printing device.

2. Description of the Related Art In printing apparatuses that print by applying liquid to a recording medium, there is a technique in which a heated heater is brought into contact with the recording medium to dry it.

Conventionally, it has been known to perform control to increase the heating temperature of a heater that contacts the surface of the recording medium opposite to the surface on which the liquid is attached when the conveyance speed of the recording medium or the amount of liquid attached is above a predetermined value ( Patent Document 1).

In the method of Patent Document 1, it is necessary to heat all the heaters regardless of the conditions, which may increase the amount of wasted electric power.

SUMMARY OF THE INVENTION An object of the present invention is to prevent omission of a printed image and to reduce the power required to heat a recording medium.

In order to solve the above problems, a heating device according to one aspect of the present invention is arranged along a conveyance path along which a recording medium to which a liquid has been applied is conveyed, and contacts the recording medium from the back side of the printed surface of the recording medium. a plurality of heating units configured to heat the recording medium by heating the recording medium; when heating the recording medium, at least one heating unit among the plurality of heating units can stop heating; When there is a plurality of heating units that are separated from the back surface of the recording medium, stop the heating, and are separated from the recording medium, the plurality of heating units are the same along the conveyance path. At least one set is selected at intervals, or a plurality of sets of the same number are selected at intervals along the conveyance path.

It is possible to prevent omission of printed images and to reduce the power required to heat the recording medium.

A diagram illustrating an example of a schematic configuration of a printing device according to an embodiment. Functional block diagram of control device Hardware configuration diagram of control device Schematic configuration diagram of the drying mechanism according to the first embodiment Diagram showing the drying mechanism where the heat roller is separated from the continuous paper Diagram showing the drying mechanism where the heat roller is separated from the continuous paper Diagram showing the drying mechanism where the heat roller is separated from the continuous paper Diagram showing the drying mechanism where the heat roller is separated from the continuous paper Diagram showing the drying mechanism where the heat roller is separated from the continuous paper Diagram showing the drying mechanism where the heat roller is separated from the continuous paper Schematic configuration diagram of a drying mechanism according to a modified example Schematic diagram of the drying mechanism according to the second embodiment Schematic diagram of the drying mechanism according to the third embodiment Schematic diagram of the drying mechanism that only stops heating and maintains contact with continuous paper

Embodiments will be described below with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components in each drawing are denoted by the same reference numerals as much as possible, and redundant description will be omitted.

[First embodiment]
A first embodiment will be described with reference to FIGS. 1 to 10. FIG. 1 is a diagram showing an example of a schematic configuration of a printing apparatus 1 according to an embodiment.

The printing device 1 shown in FIG. 1 is, for example, an inkjet recording device, and prints a liquid of a desired color onto continuous paper 5 (recording medium), which is a member to be transported (a member to be transported, an object to be heated, and an object to be dried). It has a liquid application section 2 including a liquid ejection head that ejects and applies a certain ink.

In the liquid application unit 2, for example, full-line liquid ejection heads 2k, 2c, 2m, and 2y for four colors are arranged from the upstream side in the conveyance direction of the continuous paper 5, and black, K, etc. are arranged for the continuous paper 5. , cyan C, magenta M, and yellow Y liquids are applied. Note that the types and number of colors are not limited to these.

The continuous paper 5 is let out from the unwinding roller 3 and is conveyed (moved) facing the liquid applying section 2 . The continuous sheet 5 to which the liquid has been applied by the liquid applying section 2 passes through the drying mechanism 10 (heating device) according to the present invention, and is wound up by the winding roller 4.

The control device 6 controls the operation of each part of the printing device 1.

FIG. 2 is a functional block diagram of the control device 6. As shown in FIG. As shown in FIG. 2, the control device 6 includes a main control section 61, an image input section 62, an ink adhesion amount calculation section 63, a speed setting section 64, a paper setting section 65, and a heater temperature setting section 66. , a paper conveyance control section 67, a print head control section 68, a heater power control section 69, and a heater separation control section 70.

The main control unit 61 controls the entire printing apparatus 1 .

The main control section 61 receives image data from an image input section 62 that inputs information regarding print images from the outside, setting information for the feeding speed of continuous paper 5 from a speed setting section 64, and continuous input from a paper setting section 65. Information regarding the basis weight of the ledger paper 5 is given. Further, the image data from the image input section 62 is given to an ink adhesion amount calculation section 63, where the ink adhesion amount associated with printing the image is calculated and sent to the main control section 61. Furthermore, the main control section 61 receives input from the heater temperature setting section 66 of setting information on the heating temperature of the drying mechanism 10 (heat rollers 11a to 11j, see FIG. 4).

Note that the various information set in the speed setting section 64, paper setting section 65, and heater temperature setting section 66 may be obtained by input from the user of the printing apparatus 1, or may be acquired by a sensor etc. provided in the printing apparatus 1. It may also be set based on information obtained from .

The main control unit 61 controls the paper conveyance control unit 512 to rotationally drive the unwinding roller 3 , the winding roller 4 , the conveying roller 12 , etc., and conveys the continuous paper 5 facing the liquid application unit 2 . . Then, based on the image data from the image input section 62, the print head control section 68 is controlled to drive and control the liquid ejection heads 2k, 2c, 2m, and 2y of the liquid application section 2 to eject droplets onto the continuous paper 5. to form an image.

The main control unit 61 then controls the heater power control unit 69 based on the heating temperature setting information to form an image while controlling the heating temperature of the heat rollers 11a to 11j of the drying mechanism 10 to a predetermined temperature. The continuous paper 5 is dried. Further, the main control unit 61 controls the heater separation control unit 70 to determine the number of heat rollers 11a to 11j to be separated from the continuous paper 5 conveyance path based on information such as the conveyance speed, basis weight, and heating temperature. Control.

FIG. 3 is a hardware configuration diagram of the control device 6. As shown in FIG. As shown in FIG. 3, the control device 6 physically includes a CPU (Central Processing Unit) 101, a RAM (Random Access Memory) 102 which is a main storage device, a ROM (Read Only Memory) 103, and an input device. It can be configured as a computer system including an input device 104 such as a keyboard and mouse, an output device 105 such as a display or touch panel, a communication module 106 that is a data transmission/reception device such as a network card, an auxiliary storage device 107 such as a hard disk, etc. .

Each of the functions of the control device 6 shown in FIG. This is realized by operating the memory and reading and writing data in the RAM 102 and the auxiliary storage device 107.

FIG. 4 is a schematic diagram of the drying mechanism 10 in FIG. 1. As shown in FIG. 4, the drying mechanism 10 includes ten heat rollers (heating sections) 11a to 11j and five transport rollers 12a to 12e. The heat rollers 11a to 11j and the transport rollers 12a to 12e are rotating bodies that guide the transport of the continuous paper 5. Note that the heat rollers 11a to 11j may be collectively referred to as "heat rollers 11," and the conveyance rollers 12a to 12e may be collectively referred to as "conveyance rollers 12."

The heat rollers 11a to 11j are arranged in a polygonal shape, and the outer peripheral side of each heat roller is in contact with the back surface 5a of the continuous paper 5 on the opposite side to the printed surface (the surface to which liquid is applied by the liquid applying section 2). It is located. Each heat roller is in contact with the back surface 5a of the continuous paper 5, and when placed on the conveyance path, generates heat at a predetermined temperature to heat and dry the continuous paper 5. Note that in FIG. 4 and subsequent figures, the heat roller in a heat generating state is represented by a hatched pattern, and the heat roller in a non-heating state is represented in white.

Furthermore, the heat rollers 11a to 11j are configured to be movable toward the center of the polygon. In other words, it has a range of motion in the center direction. This mechanism allows each of the heat rollers 11a to 11j to come into contact with and separate from the continuous paper 5. The drying mechanism 10 is configured to have such a plurality of heat rollers 11a to 11j so that the amount of heating can be adjusted by changing the number of heat rollers that come into contact with the continuous paper 5.

Further, the drying mechanism 10 can stop heating by at least some of the plurality of heat rollers when heating the continuous paper 5. Further, the drying mechanism 10 can stop the heat roller from generating heat by separating it from the continuous paper 5 and not using it to heat the continuous paper 5. This makes it possible to suppress wasteful power consumption. Note that the heat roller may be separated from the continuous paper 5 after the heat roller has stopped generating heat, or the heat roller may be stopped generating heat and separated from the continuous paper 5 at the same time.

A heating conveyance path for heating the continuous paper 5 is formed by the heat rollers 11a to 11j that are in contact with the continuous paper 5 and the transport rollers 12a to 12e.

The conveying rollers 12a to 12e send the continuous paper 5, which has been heated and dried by the heat rollers 11a to 11j, to the winding roller 4. At least some of the transport rollers 12a to 12e are driven to transport the continuous paper 5 in the transport direction. In this embodiment, the transport rollers 12a to 12e function as a "transport unit" that transports the continuous paper 5 along the transport path.

An example of a configuration for changing the number of heat rollers that come into contact with continuous paper 5 will be described with reference to FIGS. 5 to 10.

FIG. 5 is a diagram showing a drying mechanism in which one heat roller is separated from the continuous paper 5. As shown in FIG. In the example of FIG. 5, only one heat roller 11f among the heat rollers 11a to 11j is separated from the continuous paper 5 and heating is stopped. At this time, the contact width (wrapping angle) between the continuous paper 5 and the heat rollers 11e and 11g in the conveyance direction is larger than before the heat roller 11f is separated. Further, the distance between the heat rollers 11e and 11g is wider than the distance between other adjacent heat rollers (for example, the heat rollers 11a and 11b).

FIG. 6 is a diagram showing a drying mechanism in which two heat rollers are separated from continuous paper. In the example of FIG. 6, two of the heat rollers 11c and 11i among the heat rollers 11a to 11j are separated from the continuous paper 5 and heating is stopped. At this time, the contact width (wrapping angle) between the continuous paper 5 and the heat rollers 11b, 11d, 11h, and 11j in the conveyance direction is larger than before the heat rollers 11c and 11j are separated. Here, the contact width (wrapping angle) of the continuous paper 5 and the heat rollers 11b, 11d, and 11h in the conveyance direction is the same. Further, the distance between heat rollers 11b and 11d and the distance between heat rollers 11h and 11j are the same, and are wider than the distance between other adjacent heat rollers (for example, heat rollers 11a and 11b).

FIG. 7 is a diagram showing a drying mechanism in which three heat rollers are separated from continuous paper. In the example of FIG. 7, three heat rollers 11c, 11f, and 11i among the heat rollers 11a to 11j are separated from the continuous paper 5 and heating is stopped. At this time, the contact width (wrapping angle) between the continuous paper 5 and the heat rollers 11b, 11d, 11e, 11g, 11h, and 11j in the conveyance direction is larger than before the heat rollers 11c, 11f, and 11i are separated. Here, the contact width (wrapping angle) of the continuous paper 5 and the heat rollers 11b, 11d, 11g, and 11h in the conveyance direction is the same. Further, the spacing between heat rollers 11b and 11d, the spacing between heat rollers 11e and 11g, and the spacing between heat rollers 11h and 11j are the same, and are larger than the spacing between other adjacent heat rollers (for example, heat rollers 11a and 11b). wide.

FIG. 8 is a diagram showing a drying mechanism in which four heat rollers are separated from continuous paper. In the example of FIG. 8, four heat rollers 11b, 11d, 11f, and 11h among the heat rollers 11a to 11j are separated from the continuous paper 5 and heating is stopped. At this time, the contact width (wrapping angle) between the continuous paper 5 and the heat rollers 11a, 11c, 11e, 11g, and 11i in the conveyance direction is larger than before the heat rollers 11b, 11d, 11f, and 11h are separated. Here, the contact width (wrapping angle) of the continuous paper 5 and the heat rollers 11c, 11e, and 11g in the conveyance direction is the same. Furthermore, the intervals between the heat rollers 11a and 11c, the interval between the heat rollers 11c and 11e, the interval between the heat rollers 11e and 11g, and the interval between the heat rollers 11g and 11i are the same, and are larger than the interval between the heat rollers 11j and 11i. wide.

FIG. 9 is a diagram showing a drying mechanism in which five heat rollers are separated from continuous paper. In the example of FIG. 9, five heat rollers 11c, 11e, 11f, 11h, and 11i among the heat rollers 11a to 11j are separated from the continuous paper 5 and heating is stopped. At this time, the contact width (wrapping angle) between the continuous paper 5 and the heat rollers 11b, 11d, 11g, and 11j in the conveying direction is larger than before the heat rollers 11c, 11e, 11f, 11h, and 11i are separated. Here, the contact width (wrapping angle) of the continuous paper 5 and the heat rollers 11g and 11j in the conveyance direction is the same. Further, the distance between the heat rollers 11b and 11d is wider than the distance between the heat rollers 11a and 11b. The distance between the heat rollers 11d and 11g and the distance between the heat rollers 11g and 11i are the same and wider than the distance between the heat rollers 11b and 11d.

FIG. 10 is a diagram showing a drying mechanism in which six heat rollers are separated from continuous paper. In the example of FIG. 10, six heat rollers 11b, 11c, 11e, 11f, 11h, and 11i among the heat rollers 11a to 11j are separated from the continuous paper 5 and heating is stopped. At this time, the contact width (wrapping angle) between the continuous paper 5 and the heat rollers 11a, 11d, 11g, and 11j in the conveyance direction is larger than before the heat rollers 11b, 11c, 11e, 11f, 11h, and 11i are separated. Here, the contact width (wrapping angle) of the continuous paper 5 and the heat rollers 11d, 11g, and 11j in the conveyance direction is the same. Further, the distance between the heat rollers 11a and 11d, the distance between the heat rollers 11d and 11g, and the distance between the heat rollers 11g and 11j are the same.

As shown in FIGS. 5 to 10, when heating the continuous paper 5, at least one heat roller among the plurality of heat rollers 11a to 11j is separated from the back surface 5a of the continuous paper 5 so that the heating can be stopped. I made it. This eliminates the need for operating power for the heat roller that is not necessary for drying the continuous paper 5, suppresses wasteful power consumption, and reduces the power required for drying the continuous paper 5 by the drying mechanism 10. I can do it. In addition, during the drying process using the heat roller, the roller is always in contact with the back surface 5a of the continuous sheet 5, so that it is possible to prevent the printed image from falling out (such as ink peeling off from the printing surface) due to the roller contacting the printing surface. can. Note that separating the heat roller from the continuous paper 5 can be said to shorten the distance that the continuous paper 5 contacts the heat roller, or reduce the number of times the continuous paper 5 contacts the heat roller.

Further, the continuous paper 5 is wound around the curved surface of the heat roller and is subjected to a predetermined tension. Therefore, even if the continuous paper 5 is cockled due to the applied liquid, the cockling of the continuous paper 5 can be corrected on the curved surface of the heat roller.

Further, as shown in FIGS. 5 to 10, it is preferable to select the heat rollers to be spaced apart and to stop heating at the same intervals or in the same number as much as possible. Thereby, the heat rollers that contact and heat the continuous paper 5 can be arranged in a regular polygonal shape. Therefore, it is possible to equalize the distance and switching timing between the heated region and the non-heated region of continuous paper 5 in the conveyance path. This makes it possible to equalize the amount of heat applied to the continuous paper 5 over the entire transport path within the drying mechanism 10. Furthermore, since the intervals between adjacent heat rollers that are in contact with the continuous paper 5 are approximately the same, the tension applied to the continuous paper 5 can also be made uniform. Further, by arranging the heat rollers that contact and heat the continuous paper 5 in a substantially regular polygonal shape, it is possible to prevent the conveyance path from entering the center side. Therefore, the amount of movement of the heat roller when separating it from the continuous paper 5 can be reduced, and the heat roller moving mechanism can be downsized. Note that the term "regular polygonal shape" includes shapes in which the distance and angle between the vertices (positions of the heat roller) fall within a predetermined range that includes the numerical values of the regular polygon.

By the way, if the non-heating heat roller is not separated, there is a risk that the non-heating heat roller will come into contact with the continuous paper 5 and absorb the heat obtained from the ink, reducing the drying efficiency. In this embodiment, the heat roller that stops heating is separated from the conveyance path and does not come into contact with the continuous paper 5, so the heat roller that does not heat does not take away heat from the continuous paper 5, which improves drying efficiency. Deterioration can be prevented.

Furthermore, if the heat roller that has been changed from the heating state to the non-heating state is not separated, the continuous paper 5 will be heated with its residual heat, which may cause excessive drying. In this embodiment, the heat roller that stops heating does not come into contact with the continuous paper 5, so that excessive drying can be prevented.

Changing the number of heat rollers that come into contact with the continuous sheet 5 can be determined based on various conditions such as the conveyance speed and the amount of ink adhesion. A specific example of separation control is shown below.

In the first example, the number of distances between the heat rollers is changed depending on the basis weight of the continuous paper 5. As shown in Table 1, when the heat rollers 11a to 11j have a heating temperature of 100° C., a linear speed of 75 mpm, and an ink adhesion amount of 2 μl/inch ² , when the basis weight of the continuous paper 5 is less than 90 gms, 5 rollers are used. Separate the heat rollers and stop heating. When the basis weight is 90 gms or more and less than 120 gms, the four heat rollers are separated and heating is stopped. When the basis weight is 120 gms or more and less than 200 gms, the two heat rollers are separated and heating is stopped. When the basis weight is 200 gms or more, the number of heat rollers to be separated is 0, and all the heat rollers are in contact with the continuous paper 5.

In this way, in the first example, the smaller the basis weight of the continuous paper 5, the more the number of heat rollers that stop heating from the back side 5a of the printing surface of the continuous paper 5 is increased, and the basis weight of the continuous paper 5 is increased. The larger the value is, the fewer the number of heat rollers that stop heating from the back side 5a of the printing surface of the continuous paper 5 is reduced. In the first example, when the basis weight of the continuous sheet 5 is a first value, the number of heat rollers 11 that stop heating is greater than when the basis weight is a second value larger than the first value. It can also be expressed as

In the second example, the number of distances between the heat rollers is changed depending on the amount of ink adhering to the continuous paper 5. As shown in Table 2, under the conditions that the basis weight of the continuous paper 5 is 130 gms, the heating temperature of the heat rollers 11a to 11j is 100° C., and the linear speed is 75 mpm, if the ink adhesion amount is less than 2 μl/inch ² , The heat rollers are separated and heating is stopped. If the amount of ink adhesion is 2 μl/inch ² or more and less than 3 μl/inch ² , the two heat rollers are separated and heating is stopped. When the amount of ink adhesion is 3 μl/inch ² or more, one heat roller is separated and heating is stopped.

In this way, in the second example, the smaller the amount of ink that adheres to the continuous paper 5, the more the number of heat rollers that stop heating from the back side 5a of the printing surface of the continuous paper 5 is increased, As the amount of ink that adheres to paper 5 increases, the number of heat rollers that stop heating from the back side 5a of the printing surface of continuous paper 5 is reduced. In the second example, when the amount of droplets adhering to the continuous sheet 5 is the first value, the heat roller 11 stops heating, compared to when the amount is the second value, which is larger than the first value. It can also be expressed as a large number.

In the third example, the number of separations between the heat rollers is changed depending on the conveyance speed (linear speed) of the continuous paper 5. As shown in Table 3, under the conditions that the basis weight of the continuous paper 5 is 130 gms, the heating temperature of the heat rollers 11a to 11j is 100° C., and the ink adhesion amount is 2 μl/inch ² , the linear speed of the continuous paper 5 is 75 mpm. If the temperature is less than 1, the three heat rollers are separated and heating is stopped. When the linear speed of the continuous paper 5 is 75 mpm or more and less than 100 mpm, the two heat rollers are separated and heating is stopped. When the linear velocity of the continuous paper 5 is 100 mpm or more and less than 125 mpm, one heat roller is separated and heating is stopped. When the linear speed of continuous paper 5 is 125 mpm or more, the number of heat rollers to be separated is 0, and all the heat rollers are in contact with continuous paper 5.

In this way, in the third example, the slower the conveyance speed of continuous paper 5 is, the more the number of heat rollers that stop heating from the back side of the printing surface of continuous paper 5 is increased, and the conveyance speed of continuous paper 5 is increased. The faster the speed is, the fewer the number of heat rollers that stop heating from the back side of the printing surface of continuous paper 5 is reduced. In the third example, when the conveyance speed of the continuous sheet 5 is the first value, the number of heat rollers 11 that stop heating is greater than when the conveyance speed is the second value, which is larger than the first value. It can also be expressed as

In the fourth example, the number of distances between the heat rollers is changed depending on the set temperature (heating temperature) of the heat rollers. As shown in Table 4, under the conditions that the basis weight of the continuous paper 5 is 130 gms, the linear speed of the heat rollers 11a to 11j is 75 mpm, and the ink adhesion amount is 2 μl/inch ² , when the heating temperature is less than 80°C. , the number of heat rollers separated is 0, and all the heat rollers are in contact with the continuous paper 5. When the heating temperature is 80° C. or more and less than 100° C., one heat roller is separated and heating is stopped. When the heating temperature is 100° C. or more and less than 120° C., the two heat rollers are separated and heating is stopped. When the heating temperature is 120° C. or higher, the four heat rollers are separated and heating is stopped.

In this way, in the fourth example, the higher the temperature of the heat roller that heats the continuous paper 5, the more the number of heat rollers that stop heating from the back side of the printed surface of the continuous paper 5 is increased. The lower the temperature of the heat rollers that heat the continuous paper 5, the fewer the number of heat rollers that stop heating from the back side of the printing surface of the continuous paper 5. In the fourth example, when the temperature of the heat roller 11 that heats the continuous sheet 5 is a first value, the heat roller 11 that stops heating is more effective than when the temperature is a second value that is larger than the first value. It can also be expressed as having a small number of.

Note that the number of distances between the heat rollers may be determined by combining each of the parameters in the first to fourth examples above. For example, under conditions where the basis weight of the continuous paper 5 is 130 gms and the heating temperature of the heat roller is 100° C., even under the combination of two conditions of ink adhesion amount and linear speed, the heat rollers are spaced apart as shown in Table 5. Drying conditions can be optimized by adjusting the number of.

More specifically, as shown in Table 5, when the ink adhesion amount is less than 2 μl/inch ² and the linear speed of the continuous paper 5 is less than 75 mpm, the four heat rollers are spaced apart and heating is performed. Stop. When the ink adhesion amount is less than 2 μl/inch ² and when the linear velocity of the continuous paper 5 is 75 mpm or more and less than 100 mpm, the four heat rollers are separated and heating is stopped. When the ink adhesion amount is less than 2 μl/inch ² and when the linear velocity of the continuous paper 5 is 100 mpm or more and less than 125 mpm, the two heat rollers are separated and heating is stopped. When the ink adhesion amount is less than 2 μl/inch ² and when the linear speed of the continuous paper 5 is 125 mpm or more, one heat roller is separated and heating is stopped. If the ink adhesion amount is 2 μl/inch ² or more and less than 3 μl/inch ² and the linear speed of the continuous paper 5 is less than 75 mpm, the three heat rollers are separated and heating is stopped. When the ink adhesion amount is 2 μl/inch ² or more and less than 3 μl/inch ² and the linear speed of the continuous paper 5 is 75 mpm or more and less than 100 mpm, the two heat rollers are separated and heating is stopped. When the ink adhesion amount is 2 μl/inch ² or more and less than 3 μl/inch ² and the linear velocity of the continuous paper 5 is 100 mpm or more and less than 125 mpm, one heat roller is separated and heating is stopped. When the ink adhesion amount is 2 μl/inch ² or more and less than 3 μl/inch ² and the linear speed of the continuous paper 5 is 125 mpm or more, the number of heat rollers to be separated is 0, and all heat rollers are separated. It comes into contact with continuous paper 5. If the ink adhesion amount is 3 μl/inch ² or more and the linear velocity of the continuous paper 5 is less than 75 mpm, the two heat rollers are separated and heating is stopped. When the ink adhesion amount is 3 μl/inch ² or more and the linear velocity of the continuous paper 5 is 75 mpm or more and less than 100 mpm, one heat roller is separated and heating is stopped. When the ink adhesion amount is 3 μl/inch ² or more and the linear speed of the continuous paper 5 is 100 mpm or more and less than 125 mpm, the number of heat rollers to be separated is 0, and all heat rollers are separated from the continuous paper 5. come into contact with.

The three-stage change pattern of the number of separations between the heat rollers according to the amount of ink adhesion shown in Table 2 is under the condition of a linear speed of 75 mpm, so in Table 5, the second column from the left (linear speed of 75 mpm or more and 100 mpm or more) (less than). In Table 5, as shown in the third and fourth columns from the left, when the linear speed is higher than the linear speed conditions in Table 2, the contact time between the continuous sheet 5 and the heat roller decreases, resulting in drying. Therefore, it is possible to relatively reduce the number of separations of the heat rollers depending on the amount of ink adhesion and increase the number of heat rollers used for heating to accelerate drying of the continuous paper 5. On the other hand, as shown in the first column from the left, when the linear speed is lower than the linear speed conditions in Table 2, the contact time between the continuous paper 5 and the heat roller increases, making it easier to dry. Power consumption can be further suppressed by relatively increasing the number of separations between the heat rollers according to the amount of ink adhesion.

In addition, under the conditions at the top left of Table 5 (when the ink adhesion amount is less than 2 μl/inch ² and when the linear speed of continuous paper 5 is less than 75 mpm), when the linear speed is one step lower (linear speed (75 mpm or more and less than 100 mpm), the number of heat rollers does not increase and remains at 4, but this is because the continuous paper 5 could not be completely dried when the number of heat rollers was increased to 5. be. In addition, if the ink adhesion amount is 3 μl/inch ² or more and the linear speed of the continuous paper 5 is 125 mpm or more, the printed surface of the continuous paper 5 will not be sufficiently dried. Excluded from the roller separation control conditions.

In this way, by considering a plurality of parameters, it becomes possible to more precisely control the number of separations of the heat rollers, and it is possible to more appropriately reduce power by stopping the separated heat rollers.

In addition to the combinations of ink adhesion amount and linear speed shown in Table 5, heat under each condition as in Table 5 is also available for combinations of two or more of basis weight, ink adhesion amount, linear speed, and heating temperature. You can set the number of rollers to separate. If you control the number of separations of the heat rollers by considering all parameters such as basis weight, ink adhesion amount, linear speed, and heating temperature, you can achieve high basis weight, large ink adhesion amount, fast linear speed, and low heating temperature. The distance between the heat rollers is changed under each condition, from the conditions that are the most difficult to dry, to the conditions that are the easiest to dry, which are low basis weight, small amount of ink adhesion, slow linear speed, and high heating temperature. Therefore, it is possible to provide an optimal drying method under all usage environments of the printing apparatus 1.

In inkjet printing, the amount of heating required to completely dry the ink printed on continuous paper 5 varies depending on various control parameters of the printing process, such as the conveyance speed of continuous paper 5 and the amount of ink adhesion. If the heating is insufficient, the ink will not be completely dried, and problems such as ink peeling off from the printing surface will occur when a roller comes into contact with the printing surface in a subsequent process. On the other hand, in the case of excessive heating, overdrying may occur, and the surface of the continuous paper 5 may turn yellow (yellowing). For example, if the continuous paper 5 is a paper such as coated paper that has been made smooth by coating the surface of the base paper, and the heating temperature of the heat roller is about 140 degrees, the continuous paper 5 may be caused by some event during the printing process to cause the continuous paper to become smooth. When the conveyance of the paper 5 is stopped, the portion of the continuous paper that has been in contact with the heat roller and continues to be heated during the stop may turn yellow.

In this embodiment, as shown in Tables 1 to 5, the basis weight of the continuous paper 5, the amount of ink adhering to the continuous paper 5, the conveyance speed of the continuous paper 5, the set temperature of the heat roller, or these The number of heat rollers to be separated from the continuous paper 5 is adjusted based on the combination of parameters. This makes it possible to more appropriately set the number of heat rollers used to heat the continuous paper 5, taking into account the influence of various control parameters in the printing process, and suppresses the occurrence of under-drying or over-drying of the ink. Higher quality printing becomes possible.

Although the first embodiment exemplifies a configuration in which the drying mechanism 10 includes ten heat rollers 11a to 11j, the number of heat rollers is not limited to this. For example, if the number of heat rollers is increased to 10 or more, the range in which the amount of heating can be adjusted can be expanded, and the step size of adjustment can be divided into smaller sections, allowing for more fine-grained control.

Further, in the first embodiment, the top surface of the heat roller 11b is arranged lower than the top surface of the conveyance roller 12a. Therefore, when the heat roller 11a is separated from the continuous paper 5, the continuous paper 5 moving upstream in the conveyance direction from the heat roller 11b may come into contact with the continuous paper 5 on the conveyance roller 12a and rub against each other. Therefore, in the first embodiment, it is preferable that the position of the heat roller 11a is fixed and that it is not separated from the continuous paper 5.

[Modified example]
A modification of the first embodiment will be described with reference to FIG. 11. FIG. 11 is a schematic configuration diagram of a drying mechanism 10A according to a modification of the first embodiment.

As shown in FIG. 11, in the printing apparatus 1 of the first embodiment, the same effect can be achieved even if each of the heat rollers 11a to 11j is replaced with a curved heater 13a to 13j (heating section). The curved heaters 13a to 13j have curved contact surfaces protruding toward the outer periphery, and these contact surfaces are heated and come into contact with the continuous paper 5.

The curved heaters 13a to 13j are arranged in a polygonal shape similarly to the heat rollers 11a to 11j. Further, the curved heaters 13a to 13j, like the heat rollers 11a to 11j, are configured so that their contact surfaces can be separated from the continuous paper 5 by moving toward the center of the polygonal arrangement. The position and number of the spaced apart curved heaters can be determined by the heat roller embodiment described above.

Note that the drying mechanism 10 has a configuration in which a plurality of heating units other than the heat rollers 11a to 11j and the curved heaters 13a to 13j are arranged along the conveyance path of the continuous paper 5 so that they can come into contact with and separate from the continuous paper 5. But that's fine.

[Second embodiment]
A second embodiment will be described with reference to FIG. 12. FIG. 12 is a schematic configuration diagram of a drying mechanism 10B according to the second embodiment.

As shown in FIG. 12, the drying mechanism 10B includes a large diameter heat roller 15 at the center surrounded by a plurality of heat rollers 14a to 14i arranged in a polygonal shape. The large-diameter heat roller 15 contacts the back surface 5a of the continuous paper 5 after being heated by the heat rollers 14a to 14i to further heat it. The continuous paper 5 heated and dried by the large-diameter heat roller 15 is sent to the take-up roller 4 by conveyance rollers 16a to 16e.

In the second embodiment, the drying mechanism 10B further includes the large-diameter heat roller 15, so that in addition to heating control by the plurality of heat rollers 14a to 14i, the large-diameter heat roller 15 also heats and dries the continuous paper 5. Since the continuous paper 5 can be dried more reliably.

Further, the heat rollers 14b to 14h can also be moved toward and away from the continuous paper 5 in the same manner as in the embodiment described above. Further, it is preferable that the position of the heat roller 14a is fixed so that it does not separate from the continuous paper 5. By separating the heat roller 14a toward the center of the polygonal arrangement, it is possible to avoid contact with the continuous paper 5 passing between the conveyance rollers 16c and 16d.

[Third embodiment]
A third embodiment will be described with reference to FIG. FIG. 13 is a schematic configuration diagram of a drying mechanism 10C according to the third embodiment.

As shown in FIG. 13, in the drying mechanism 10C, the arrangement of the plurality of heat rollers 17a to 17f is different from the polygonal arrangement of the first and second embodiments.

The plurality of heat rollers 17a to 17f are arranged in an arc along the conveyance path of the continuous paper 5. The plurality of heat rollers 17a to 17f are arranged in this arcuate conveyance path so that the outer peripheral side of each heat roller is in contact with the back surface 5a of the continuous paper 5 on the side opposite to the printed surface. Further, the heat rollers 17a to 17f are configured to be movable toward the center of the arc shape, thereby being configured to be able to separate from the continuous paper 5. The conditions for the movement of the heat rollers 17a to 17f can be the same as in the embodiment described above.

The drying mechanism 10C also includes guide rollers 18a and 18b that guide the continuous paper 5 to the heat rollers 17a to 17f, and guides the continuous paper 5 that has passed through the heat rollers 17a to 17f to be sent to the winding roller 4. The guide rollers 18c to 18h are provided.

Note that the arrangement of the plurality of heat rollers 17a to 17f is not limited to the arc shape shown in FIG. 13, but may be a straight line or a curved shape other than an arc shape. In short, the plurality of heat rollers 17a to 17f of the drying mechanism 10C need only be arranged at least along the conveyance path of the continuous paper 5.

The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. Design changes made by those skilled in the art as appropriate to these specific examples are also included within the scope of the present disclosure as long as they have the characteristics of the present disclosure. The elements included in each of the specific examples described above, their arrangement, conditions, shapes, etc. are not limited to those illustrated, and can be changed as appropriate. The elements included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

In each of the above embodiments, the recording medium is explained as an example in which continuous paper 5 is used, but the recording medium is not limited to this. In addition to such recording media (printed materials), materials such as wallpaper, sheets for electronic circuit boards such as prepreg may also be used. Further, the recording medium is not limited to the form in which it is directly wrapped around a roller and conveyed, but may be in a form in which a belt is wound around the roller instead of the continuous paper 5 and the belt sheet material is attracted to the belt surface and conveyed. .

In the embodiment described above, the drying mechanisms 10, 10A, 10B, and 10C have exemplified the configuration in which the continuous paper 5 is heated and dried. The present invention is not limited to a configuration in which the water is completely removed and heated to a dry state, but also includes a configuration in which the ink on the continuous paper 5 is heated until the moisture content is reduced. That is, the drying mechanisms 10, 10A, 10B, and 10C only need to function as heating devices that heat at least the continuous paper 5 and bring the ink close to a dry state.

In the embodiment described above, when stopping heating by some of the plurality of heating parts (heat rollers, curved heaters) of the drying mechanisms 10, 10A, 10B, 10C, the heating part to stop heating is separated from the continuous paper 5. Although a configuration has been exemplified in which the heating is stopped, a configuration in which only the heating is stopped and contact with the continuous paper 5 is maintained may be used. FIG. 14 is a diagram showing an example of the configuration of a drying mechanism 10D that only stops heating and maintains contact with continuous paper 5. For example, in the first embodiment, the position of the heat roller 11a is fixed and heating is not stopped. However, as shown in FIG. 14, heating of the heat roller 11a can be stopped. Since the position of the heat roller 11a is fixed, the conveyance path from the upstream side in the conveyance direction of the continuous paper 5 to the heat roller 11a does not change. Therefore, there are more options for heat rollers that stop heating.

In the embodiment described above, the heating units (heat rollers, curved heaters) that are spaced apart from the continuous paper 5 to stop heating are selected at the same intervals or in the same number, and the heat rollers used for heating the continuous paper 5 are arranged approximately at the same distance. Although a configuration in which the heating parts are arranged in a polygonal shape is illustrated, the method of selecting the heating parts for stopping heating is not limited to this, and for example, a predetermined number may be selected at random. Further, in the above embodiment, the number of heating units that are continuously spaced apart from the continuous paper 5 is exemplified as two, but three or more heating units may be continuously spaced apart.

In the above embodiment, a configuration was illustrated in which the heating unit (heat roller, curved heater) does not come into contact with the printed surface of the continuous paper 5, but this does not mean that it must not come into contact with the printed surface throughout the conveyance process. A configuration in which a conveyance roller or the like comes into contact with the printed surface may be used as long as the printed surface is dry. In addition, it is not necessary that all the heating units heat the continuous paper 5 from the back side 5a. For example, if the heating unit can heat the continuous paper 5 without contacting the printed surface, such as an air dryer or a halogen heater, it can heat the continuous paper 5 from the printed surface side. A configuration may also be used. However, if the continuous paper 5 is heated while being in contact with it, it is necessary to heat it from the back side 5a side.

In addition to recording images such as letters and figures onto a recording medium using liquid such as ink, printing devices also record images with no meaning such as patterns using ink or other liquid for the purpose of decoration or decoration. May be applied in liquid form.

In the present application, the liquid applied to the recording medium is not particularly limited, but preferably has a viscosity of 30 mPa·s or less at room temperature and pressure, or when heated or cooled. More specifically, solvents such as water and organic solvents, coloring agents such as dyes and pigments, functional materials such as polymerizable compounds, resins, and surfactants, and biocompatible materials such as DNA, amino acids, proteins, and calcium. , edible materials such as natural pigments, etc., and these include, for example, inkjet inks, surface treatment liquids, constituent elements of electronic devices and light emitting devices, and formation of electronic circuit resist patterns. It can be used for purposes such as a liquid for use in liquids, a material liquid for three-dimensional modeling, and the like.

When a liquid ejection head is used as a liquid application means, piezoelectric actuators (laminated piezoelectric elements and thin film piezoelectric elements), thermal actuators using electrothermal conversion elements such as heating resistors, vibrations, etc. are used as energy generation sources for ejecting liquid. This includes those that use an electrostatic actuator consisting of a plate and a counter electrode.

Note that printing in this application has the same meaning as image formation, recording, printing, printing, etc.

1 Printing device 2 Liquid applying section 5 Continuous paper (recording medium)
10, 10A, 10B, 10C, 10D Drying mechanism (heating device)
11, 14, 17 Heat roller (heating section)
13 Curved heater (heating part)

JP2016-78428A

Claims (8)

a plurality of heating units arranged along a conveyance path along which a recording medium to which a liquid has been applied are conveyed, and heating the recording medium by contacting it from the back side of the printed surface of the recording medium;
When heating the recording medium, at least one heating unit among the plurality of heating units can stop heating ;
separating the heating unit that stops heating from the back surface of the recording medium;
When there are a plurality of heating units that stop the heating and are separated from the recording medium, at least one of the plurality of heating units is selected at the same interval along the conveyance path. , or a plurality of sets of the same number are selected at intervals along the conveyance path;
heating device. The plurality of heating units are arranged in a polygonal shape along the conveyance path,
The heating device according to claim 1 . Among the plurality of heating units, heating units that are brought into contact with the recording medium to heat the recording medium are arranged in a regular polygonal shape.
The heating device according to claim 2 . When the basis weight of the recording medium is a first value, the number of heating parts that stop heating is larger than when the basis weight is a second value larger than the first value. The heating device according to any one of items 1 to 3 . When the amount of droplets adhering to the recording medium is a first value, the number of heating parts that stop heating is larger than when the amount is a second value larger than the first value. The heating device according to any one of claims 1 to 4 , wherein: When the conveyance speed of the recording medium is a first value, the number of heating parts that stop heating is larger than when the conveyance speed of the recording medium is a second value larger than the first value. The heating device according to any one of items 1 to 5 . When the temperature of the heating device that heats the recording medium is a first value, the number of heating units that stop heating is smaller than when the temperature is a second value larger than the first value. The heating device according to any one of claims 1 to 6 , characterized by: a liquid application unit that applies liquid to the recording medium being conveyed;
The heating device according to any one of claims 1 to 7 ,
A printing device comprising:

Images