Drying apparatus and drying method

Abstract

This invention provides a drying apparatus and drying method that contribute to improving the color reproduction of printed images. [Solution] The drying apparatus comprises a drying unit that dries the fabric to which a pretreatment solution has been applied before the ink containing the pigment is applied to the fabric, and a control unit. The control unit controls the drying unit and dries the fabric to which the pretreatment solution has been applied until the target drying rate is 82% or more and 95% or less (S12~S14, S22~S24). The target drying rate indicates the ratio of the target change amount to the weight of the target liquid. The weight of the target liquid indicates the sum of the weight of the solvent component contained in the pretreatment solution applied to the fabric at the time before the drying process and the weight of the water contained in the area of ​​the fabric to which the pretreatment solution is applied at the time before the pretreatment solution is applied to the fabric. The target change amount indicates the amount by which the weight of the area of ​​the fabric to which the pretreatment solution is applied changes due to the drying process.

Description

Technical Field

[0001] The present invention relates to a drying device and a drying method.

Background Art

[0002] The inkjet printing method described in Patent Document 1 includes a pretreatment step, a drying step, and a printing step. The pretreatment step, the drying step, and the printing step are executed in this order: pretreatment step, drying step, printing step. The pretreatment step applies a pretreatment liquid to a printing medium. The drying step dries the printing medium to which the pretreatment liquid has been applied. The printing step performs printing on the dried printing medium.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the above inkjet printing method, depending on the degree of drying of the pretreatment liquid in the drying step, the color development of the image printed on the printing medium in the printing step may deteriorate.

[0005] An object of the present invention is to provide a drying device and a drying method that contribute to improving the color development of a printed image.

Means for Solving the Problems

[0006] A drying apparatus according to a first aspect of the present invention comprises a drying unit for drying a fabric to which a pretreatment liquid has been applied before an ink containing a pigment is applied to the fabric, and a control unit, wherein the control unit controls the drying unit and performs a drying process to dry the fabric to which the pretreatment liquid has been applied until the target drying rate is 82% or more and 95% or less, wherein the target drying rate represents the ratio of the target change amount to the weight of the target liquid, the weight of the target liquid represents the sum of the weight of the solvent component contained in the pretreatment liquid applied to the fabric at the time before the drying process and the weight of the water contained in the region of the fabric to which the pretreatment liquid is applied at the time before the pretreatment liquid is applied to the fabric, and the target change amount represents the amount by which the weight of the region of the fabric changes due to the drying process.

[0007] According to the first embodiment, the fabric is sent to the printing process when its drying rate is between 82% and 95%. Therefore, the drying device contributes to improving the color development of the printed image.

[0008] In the drying apparatus, the control unit may, in the drying process, control the drying unit to perform a primary drying process in which the fabric to which the pretreatment liquid has been applied is dried, and after the primary drying process, control the drying unit to perform a secondary drying process in which the fabric to which the pretreatment liquid has been applied is dried until the target drying rate is 82% or more and 95% or less.

[0009] In this case, the fabric is dried by the primary drying process before the secondary drying process. Therefore, the amount of fabric dried in the secondary drying process is less compared to when the primary drying process is not performed. Thus, the drying device contributes to making it easier to control the target drying rate between 82% and 95%.

[0010] In the drying apparatus, the drying section includes a non-contact drying section for drying the fabric in a non-contact manner and a contact drying section for drying the fabric in a contact manner, and the control unit may, in the primary drying process, control the non-contact drying section to dry the fabric to which the pretreatment liquid has been applied, and in the secondary drying process, control the contact drying section to dry the fabric to which the pretreatment liquid has been applied.

[0011] For example, in a contact-type drying system, when removing fabric from the contact drying section, it is necessary to release contact with the fabric. On the other hand, in a non-contact type drying system, there is no need to contact or release contact with the fabric. For this reason, the non-contact type is more production-efficient than the contact type.

[0012] The drying apparatus first dries the fabric using a non-contact method, which is more efficient than a contact method, and then dries it again using a contact method to flatten the surface fibers. When printing is performed with the surface fibers of the fabric flattened, the quality of the printed image is improved compared to when printing is performed with the surface fibers standing upright. Therefore, the drying apparatus contributes to improving both production efficiency and the quality of the printed image.

[0013] In the drying apparatus, the control unit dries the fabric coated with the pretreatment liquid in the primary drying process until the primary drying rate is 79% or more and 97% or less, wherein the primary drying rate represents the ratio of the primary change amount to the weight of the target liquid, and the primary change amount represents the amount by which the weight of the region of the fabric changes due to the primary drying process.

[0014] In this case, the drying apparatus becomes easier to control so that the target drying rate approaches a median value between 82% and 95%. Therefore, the drying apparatus further contributes to improving the color reproduction of printed images.

[0015] In the drying apparatus, the control unit may drive the non-contact drying unit in the primary drying process until the fabric to which the pretreatment liquid has been applied receives a heat quantity of 2500 J or more and 4100 J or less.

[0016] In this case, the drying device contributes to drying the fabric while suppressing discoloration during the primary drying process.

[0017] A drying method according to a second aspect of the present invention is a drying method for controlling a drying apparatus equipped with a drying section for drying a fabric to which a pretreatment liquid has been applied before an ink containing a pigment has been applied to the fabric, comprising a drying process for controlling the drying section and drying the fabric to which the pretreatment liquid has been applied until the target drying rate is 82% or more and 95% or less, wherein the target drying rate represents the ratio of the target change amount to the weight of the target liquid, the weight of the target liquid represents the sum of the weight of the solvent component contained in the pretreatment liquid applied to the fabric at the time before the drying process and the weight of the water contained in the region of the fabric to which the pretreatment liquid is applied at the time before the pretreatment liquid is applied to the fabric, and the target change amount represents the amount by which the weight of the region of the fabric changes due to the drying process.

[0018] The second embodiment contributes to achieving the same effects as the first embodiment. [Brief explanation of the drawing]

[0019] [Figure 1] This is a schematic plan view of printing system 1. [Figure 2] This is a block diagram showing the electrical configuration of the drying apparatus 9. [Figure 3] This diagram illustrates the behavior of the flocculant S2 during the drying process. [Figure 4] This diagram illustrates the behavior of resin component S3 during the drying process. [Figure 5] This diagram illustrates the formation of the white ink layer during the printing process for each evaporation amount of solvent component S1. [Figure 6] This is a diagram of fabric F. [Figure 7] This table explains how to calculate the initial moisture content of fabric F. [Figure 8] This table explains how to calculate each parameter in Example 1. [Figure 9] This table shows the results of the L* value evaluation test and the color difference evaluation test. [Figure 10] This graph shows the results of an L* value evaluation test, with the target drying rate on the horizontal axis and the target L* value on the vertical axis. [Figure 11] This graph shows the results of an L* value evaluation test, with the primary drying rate on the horizontal axis and the target L* value on the vertical axis. [Figure 12] This graph shows the results of a color difference evaluation test, with the horizontal axis representing primary heat energy and the vertical axis representing the target color difference ΔE*ab. [Figure 13] This is a flowchart of the main process. [Figure 14] This figure shows the primary drying setting information 921. [Figure 15] This figure shows the secondary drying setting information 922. [Modes for carrying out the invention]

[0020] A printing system 1 according to one embodiment of the present invention will be described with reference to the drawings. The printing system 1 shown in Figure 1 is a system that transports a plurality of platens 10 and performs various processes on the fabric F placed on each of the plurality of platens 10. Each process is pre-processing, printing, and post-processing. The printing system 1 performs pre-processing, printing, and post-processing sequentially in the order of pre-processing, printing, and post-processing.

[0021] In the pretreatment, coating and drying processes are performed in the order of coating followed by drying. In this embodiment, the drying process is performed in two stages. The drying process includes oven treatment and heat pressing. The oven treatment and heat pressing process are performed in the order of oven treatment followed by heat pressing.

[0022] In the following, oven processing will also be referred to as "primary drying processing," and heat pressing processing as "secondary drying processing." Details of each process will be described later.

[0023] Referring to Figure 1, the configuration of the printing system 1 will be described. In the following, the top, bottom, left, right, back of the paper, and front of the paper in Figure 1 will be referred to as the rear, front, left, right, bottom, and top of the printing system 1, respectively.

[0024] The printing system 1 comprises multiple printers 2A, 2B, 2C, 2D, a coating device 3A, multiple gas ovens 4A, 4B, 4C, 4D, multiple heat press devices 5A, 5B, multiple post-processing devices 6A, 6B, 6C, 6D, 6E, 6F, a transport device 7, and a platen 10.

[0025] The platen 10 has a plate-like shape. The platen 10 extends in the front-to-back and left-to-right directions. A fabric F is placed on the platen 10. The material of the fabric F is, for example, 100% cotton. The platen 10 is conveyed by a conveying device 7.

[0026] The multiple printers 2A, 2B, 2C, and 2D are each devices that perform printing. The printing process involves applying liquid ink to the fabric F on the platen 10 and printing an image. Hereinafter, the image printed on the fabric F by the printing process will be referred to as the "printed image". In this embodiment, printers 2A, 2B, 2C, and 2D are each inkjet printers. Printers 2A, 2B, 2C, and 2D each print on the fabric F on the platen 10.

[0027] Printer 2A is positioned to the right of the main path 71, which will be described later. For example, the side on which the entrances for the platen 10 to printers 2A, 2B, 2C, and 2D are provided is considered the front. In this case, the left side of printer 2A becomes the front of printer 2A.

[0028] Printer 2B is positioned to the left of Printer 2A. The front of Printer 2B faces the front of Printer 2A, with the main path 71 in between.

[0029] Printer 2C is positioned behind Printer 2A. The front of Printer 2C faces the same direction as the front of Printer 2A.

[0030] Printer 2D is positioned to the left of Printer 2C. The front of Printer 2D faces the front of Printer 2C, with the main path 71 in between.

[0031] Printers 2B, 2C, and 2D have the same structure as printer 2A. Therefore, the structure of printer 2A will be described below, and the structures of printers 2B, 2C, and 2D will be omitted. Printer 2A includes an inkjet head 21, a main scanning transport mechanism 22, and a sub-scanning transport mechanism 23.

[0032] The inkjet head 21 includes nozzles (not shown). The inkjet head 21 ejects ink from the nozzles by driving a head drive element (not shown). The ink colors are, for example, white (W), black (K), yellow (Y), cyan (C), and magenta (M). The inks constitute the printed image.

[0033] The ink may also contain spot colors, such as orange (OR) and green (GR).

[0034] The main scanning transport mechanism 22 transports the inkjet head 21 in the main scanning direction by driving a main scanning motor (not shown). In printer 2A, the main scanning direction is the front-to-back direction. The sub-scanning transport mechanism 23 transports the platen 10 in the sub-scanning direction by driving a sub-scanning motor (not shown). In printer 2A, the sub-scanning direction is the left-to-right direction.

[0035] Printer 2A controls the main scanning transport mechanism 22 and the sub-scanning transport mechanism 23 to move the fabric F relative to the inkjet head 21 in the main scanning direction and the sub-scanning direction. While moving the fabric F relative to the inkjet head 21, Printer 2A controls the inkjet head 21 to eject ink from the nozzles. This performs a printing process in which ink is applied to the fabric F, and an image is printed on the fabric F.

[0036] The coating device 3A is a device that performs the coating process. The coating process is performed before the printing process. The coating process involves applying a pre-treatment solution to the fabric F. In other words, the pre-treatment solution is applied to the fabric F before the ink is applied to the fabric F.

[0037] The pretreatment solution is a base coat agent. The pretreatment solution improves ink fixation to fabric F and enhances ink color development.

[0038] The coating device 3A is positioned in front of the printer 2A and to the right of the main path 71. For example, the side on which the platen 10 enters the coating device 3A is considered the front. In this case, the left side of the coating device 3A is the front of the coating device 3A.

[0039] The coating device 3A comprises a coating unit 31 and a transport path 32. In this embodiment, the coating unit 31 is a spray. The coating unit 31 sprays the pretreatment liquid. The coating unit 31 may also be a discharge head, a coating spatula, or the like.

[0040] The transport path 32 branches off to the right from the main path 71 (described later) and extends to the coating device 3A. The transport path 32 transports the platen 10 in the left-right direction, driven by a transport motor (not shown) of the transport path 32. The transport path 32 has the same structure as the transport path 49 (described later). Therefore, the explanation of the structure of the transport path 32 is omitted.

[0041] In the coating apparatus 3A, with the platen 10 positioned directly below the coating section 31 via the transport path 32, the coating section 31 sprays the pretreatment liquid onto the fabric F on the platen 10. This performs a coating process in which the pretreatment liquid is applied to the fabric F.

[0042] The multiple gas ovens 4A, 4B, 4C, and 4D are each devices for oven processing. Oven processing is performed after the coating process and before the printing process. Oven processing is a process that evaporates the solvent components in the pretreatment solution applied to the fabric F by the coating process by drying the fabric F in a high-temperature atmosphere. This improves the fixation of the solute in the pretreatment solution to the fabric F.

[0043] Gas ovens 4A, 4B, 4C, and 4D are positioned between printers 2A and 2B and coating device 3A in the front-to-back direction. The relative positions of gas ovens 4A, 4B, 4C, and 4D are the same as the relative positions of printers 2A, 2B, 2C, and 2D.

[0044] Multiple gas ovens 4A, 4B, 4C, and 4D have similar structures. Therefore, the structure of gas oven 4A will be described as an example, and the structures of gas ovens 4B, 4C, and 4D will be omitted.

[0045] The gas oven 4A includes a heater 44, a fan 45, and a conveyor path 49. The heater 44 includes a gas burner 441 as shown in Figure 2. The heater 44 heats the air inside the gas oven 4A by driving the gas burner 441.

[0046] Fan 45 is a blower. Fan 45 includes a fan motor 451 as shown in Figure 2. Driven by the fan motor 451, fan 45 blows air heated by heater 44 towards the fabric F on platen 10 in gas oven 4A. In this way, gas oven 4A performs a non-contact oven drying process for the fabric F.

[0047] The conveying path 49 branches off to the right from the main path 71 (described later) and extends to the gas oven 4A. The conveying path 49 transports the platen 10 in the left-right direction, driven by a conveying motor of the conveying path 49 (not shown). Therefore, the direction of transport in the conveying path 49 is left-right.

[0048] In this embodiment, the transport path 49 is composed of belt conveyors 491 and 492. Belt conveyor 491 is positioned at the front end of the transport path 49. Belt conveyor 492 is positioned at the rear end of the transport path 49. Belt conveyors 491 and 492 extend parallel to each other in the left-right direction. The respective rotation axes of belt conveyors 491 and 492 extend in the front-rear direction.

[0049] The multiple heat press devices 5A and 5B are each devices that perform heat press processing. Heat press processing is performed after oven processing and before printing processing.

[0050] Heat pressing is a process that evaporates the solvent components in the pretreatment solution remaining on the fabric F after oven processing by applying high temperature and pressure to the fabric F. This improves the fixation of the solute in the pretreatment solution to the fabric F. Furthermore, heat pressing flattens the nap of the printed surface of the fabric F, making the printed surface of the fabric F flat. This improves the print quality on the fabric F by printers 2A, 2B, 2C, and 2D.

[0051] The heat press devices 5A and 5B are positioned in the front-to-back direction between the printers 2A and 2B and the gas ovens 4C and 4D. The relative positions of the heat press devices 5A and 5B are the same as the relative positions of the printers 2A and 2B.

[0052] The heat press device 5B has the same structure as the heat press device 5A. Therefore, the structure of the heat press device 5A will be described below, and the structure of the heat press device 5B will be omitted.

[0053] The heat press apparatus 5A comprises a heater 52, a press section 51, and a transport path 53. The heater 52 includes a heat-generating resistor 521 as shown in Figure 2. The heater 52 heats the press section 51 by driving the heat-generating resistor 521.

[0054] The pressing section 51 has a plate shape. The pressing section 51 includes a pressure control valve 511 as shown in Figure 2. The pressing section 51 moves vertically by air pressure or hydraulic pressure when driven by the pressure control valve 511.

[0055] The press section 51 moves downward while heated by the heater 52, bringing it into contact with the surface of the fabric F. This causes the press section 51 to heat the fabric F and apply pressure to the platen 10. In this way, the heat press device 5A performs a contact-type heat press treatment to dry the fabric F.

[0056] The transport path 53 branches off to the right from the main path 71 (described later) and extends to the heat press device 5A. The transport path 53 transports the platen 10 in the left-right direction, driven by a transport motor (not shown) of the transport path 53. The transport path 53 has the same structure as the transport path 49. Therefore, a description of the structure of the transport path 53 is omitted.

[0057] In the heat press apparatus 5A, with the platen 10 positioned directly below the press section 51 by the transport path 53, the press section 51, heated by the heater 52, applies pressure to the fabric F. This performs a heat press process in which the fabric F is subjected to high temperature pressure.

[0058] The multiple post-processing devices 6A, 6B, 6C, 6D, 6E, and 6F are each devices that perform post-processing. Post-processing is performed after the printing process. Post-processing involves drying the fabric F in a high-temperature atmosphere to evaporate the water in the ink applied to the fabric F during the printing process. This improves the fixation of the pigment in the ink to the fabric F.

[0059] Multiple post-processing units 6A, 6B, 6C, 6D, 6E, and 6F are positioned behind printers 2C and 2D. The relative positions of each of the multiple post-processing units 6A, 6B, 6C, and 6D are the same as the relative positions of each of the multiple printers 2A, 2B, 2C, and 2D.

[0060] Furthermore, multiple post-processing units 6E and 6F are arranged horizontally with the main path 71 in between. The multiple post-processing units 6E and 6F are positioned behind the multiple post-processing units 6C and 6D. Each of the multiple post-processing units 6A, 6B, 6C, 6D, 6E, and 6F has a structure similar to that of the gas oven 4A. Therefore, a description of the structure of the multiple post-processing units 6A, 6B, 6C, 6D, 6E, and 6F is omitted.

[0061] The conveying device 7 conveys the platen 10 so that coating, oven processing, heat pressing, printing, and post-processing are performed sequentially. The conveying device 7 includes a main path 71 and transfer mechanisms 81 to 89.

[0062] The main route 71 has a two-story structure. The main route 71 comprises a forward route 72, a return route (not shown), and elevator mechanisms 74 and 75. The forward route 72 extends in the front-to-back direction from in front of the coating device 3A to behind the post-treatment devices 6E and 6F on the second floor. The return route extends in the front-to-back direction from in front of the coating device 3A to behind the post-treatment devices 6E and 6F on the first floor. That is, the return route is located directly below the forward route 72 and extends parallel to the forward route 72.

[0063] The forward path 72 transports the platen 10 from front to back, driven by a transport motor of the forward path 72 (not shown). In this embodiment, the forward path 72 is composed of a pair of belt conveyors 721 and 722.

[0064] Belt conveyor 721 is positioned at the left end of the forward path 72. Belt conveyor 722 is positioned at the right end of the forward path 72. Belt conveyors 721 and 722 extend parallel to each other in the front-to-back direction. The respective axes of rotation of belt conveyors 721 and 722 extend in the left-to-right direction.

[0065] The return path has the same structure as the outward path 72. The return path transports the platen 10 from rear to front, driven by a transport motor for the return path (not shown).

[0066] Elevator mechanism 74 is located at the front end of the main path 71. Elevator mechanism 75 is located at the rear end of the main path 71. Therefore, the outbound path 72 and the return path are located between elevator mechanism 74 and elevator mechanism 75 in the longitudinal direction.

[0067] The elevator mechanisms 74 and 75 move up and down to the same height as the outbound path 72 and the same height as the return path, respectively, driven by their respective lifting motors (not shown). The same height as the outbound path 72 represents the second floor. The same height as the return path represents the first floor. Furthermore, the elevator mechanisms 74 and 75 transport the platen 10 in the forward and backward directions, respectively, driven by their respective transport motors (not shown).

[0068] In this embodiment, the elevator mechanism 74 is composed of a pair of belt conveyors 741 and 742. Belt conveyor 741 is located at the left end of the elevator mechanism 74. Belt conveyor 742 is located at the right end of the elevator mechanism 74. Belt conveyors 741 and 742 extend parallel to each other in the front-rear direction. The respective axes of rotation of belt conveyors 741 and 742 extend in the left-right direction.

[0069] Elevator mechanism 75 has the same structure as elevator mechanism 74. Therefore, the explanation of the structure of elevator mechanism 75 is omitted.

[0070] The transfer mechanisms 81-89 are positioned between the belt conveyors 721 and 722 in the left-right direction. On the forward path 72, the transfer mechanisms 81-89 are arranged in the order of 81, 82, 83, 84, 85, 86, 87, 88, and 89 from front to back.

[0071] Each of the transfer mechanisms 81 to 89 transports the platen 10 in the left-right direction and transfers the platen 10 between the forward path 72 and the transport mechanism of the adjacent device. For example, transfer mechanism 81 transfers the platen 10 between the forward path 72 and the transport path 32 of the coating device 3A.

[0072] The transfer mechanism 82 transfers the platen 10 between the forward path 72 and the transport path 49 of the gas oven 4A. Furthermore, the transfer mechanism 82 transfers the platen 10 between the forward path 72 and the transport path of the gas oven 4B (not shown).

[0073] The transfer mechanism 84 transfers the platen 10 between the forward path 72 and the transport path 53 of the heat press device 5A. Furthermore, the transfer mechanism 84 transfers the platen 10 between the forward path 72 and the transport path of a heat press device 5B (not shown).

[0074] The transfer mechanism 85 transfers the platen 10 between the forward path 72 and the sub-scanning transport mechanism 23 of printer 2A via the connecting transport path 85A. Furthermore, the transfer mechanism 85 transfers the platen 10 between the forward path 72 and the sub-scanning transport mechanism of printer 2B (not shown) via the connecting transport path 85B.

[0075] The transfer mechanism 86 transfers the platen 10 between the forward path 72 and the sub-scanning transport mechanism of printer 2C (not shown) via the connecting transport path 86A. Furthermore, the transfer mechanism 86 transfers the platen 10 between the forward path 72 and the sub-scanning transport mechanism of printer 2D (not shown) via the connecting transport path 86B.

[0076] Transfer mechanisms 81, 83-89 each have the same structure as transfer mechanism 82. Therefore, the structure of transfer mechanism 82 will be described below, and the explanation of the structures of transfer mechanisms 81, 83-89 will be omitted.

[0077] In this embodiment, the transfer mechanism 82 moves up and down between a position below the forward path 72 and a position above the forward path 72 by the drive of a lifting motor (not shown) of the transfer mechanism 82. Furthermore, the transfer mechanism 82 rotates the platen 10 on the transfer mechanism 82 in a clockwise or counterclockwise direction in a plan view by the drive of a rotary motor (not shown).

[0078] In this embodiment, the transfer mechanism 82 is composed of belt conveyors 821 and 822. Belt conveyor 821 is positioned at the front end of the transfer mechanism 82. Belt conveyor 822 is positioned at the rear end of the transfer mechanism 82. Belt conveyors 821 and 822 extend parallel to each other in the left-right direction. The respective rotation axes of belt conveyors 821 and 822 extend in the front-rear direction.

[0079] Referring to Figure 1, the operation flow of the printing system 1 will be explained below. For convenience, it will be assumed that, at the start of operation by the printing system 1, the transfer mechanisms 81 to 89 are each positioned below the forward path 72. Furthermore, it will be assumed that the elevator mechanisms 74 and 75 are each positioned at the same height as the forward path 72.

[0080] The user attaches the fabric F to the platen 10 while the platen 10 is positioned on the elevator mechanism 74. The elevator mechanism 74 transports the platen 10 backward and hands it over to the forward path 72.

[0081] The forward path 72 transports the platen 10 backward to the transfer mechanism 81. The transfer mechanism 81 rises above the forward path 72. As a result, the platen 10 is transferred from the forward path 72 to the transfer mechanism 81. The transfer mechanism 81 rotates the platen 10 90° clockwise in a plan view and transports the platen 10 to the right. As a result, the platen 10 is transferred from the transfer mechanism 81 to the transport path 32.

[0082] The coating device 3A performs the coating process. Once the coating process by the coating device 3A is complete, the transport path 32 transports the platen 10 to the left and hands it over to the transfer mechanism 81. The transfer mechanism 81 rotates the platen 10 90° counterclockwise in a plan view and lowers it to a position below the forward path 72. This transfers the platen 10 from the transfer mechanism 81 to the forward path 72.

[0083] The manner in which the platen 10 is transferred by each of the transfer mechanisms 82 to 89 is the same as the manner in which the platen 10 is transferred by transfer mechanism 81. For this reason, the explanation of how the platen 10 is transferred by each of the transfer mechanisms 82 to 89 will be omitted or simplified below.

[0084] The forward path 72 transports the platen 10 backward to either the transfer mechanism 82 or the transfer mechanism 83. Whether the platen 10 is transported to the transfer mechanism 82 or 83 is determined by which of the gas ovens 4A, 4B, 4C, or 4D is used for oven processing. For example, let's explain the case where oven processing is performed by gas oven 4A. In this case, the platen 10 is transported to the transfer mechanism 82 and transferred from the forward path 72 to the transfer mechanism 82. The transfer mechanism 82 transports the platen 10 to the right and hands it over to the transport path 49.

[0085] The gas oven 4A performs the oven processing. Once the oven processing by the gas oven 4A is complete, the conveyor path 49 conveys the platen 10 to the left and hands it over to the transfer mechanism 82. The transfer mechanism 82 hands the platen 10 over to the outbound path 72.

[0086] The forward path 72 transports the platen 10 to the rear and hands it over to the transfer mechanism 84. For example, let's explain the case where heat pressing is performed by the heat press device 5A. In this case, the transfer mechanism 84 transports the platen 10 to the right and hands it over to the transport path 53.

[0087] The heat press device 5A performs the heat press process. Once the heat press process by the heat press device 5A is complete, the transport path 53 transports the platen 10 to the left and hands it over to the transfer mechanism 84. The transfer mechanism 84 hands the platen 10 over to the forward path 72.

[0088] The forward path 72 transports the platen 10 backward to either the transfer mechanism 85 or the transfer mechanism 86. Whether the platen 10 is transported to the transfer mechanism 85 or 86 is determined by which of the printers 2A, 2B, 2C, or 2D performs the printing process. For example, let's consider the case where the printing process is performed by printer 2A. In this case, the platen 10 is transported to the transfer mechanism 85 and handed over from the forward path 72 to the transfer mechanism 85. The transfer mechanism 85 transports the platen 10 to the right and hands it over to the sub-scanning transfer mechanism 23 via the connecting transport path 85A.

[0089] Printer 2A performs the printing process. Once the printing process by printer 2A is complete, the sub-scanning transport mechanism 23 transports the platen 10 to the left and hands it over to the transfer mechanism 85 via the connecting transport path 85A. The transfer mechanism 85 hands over the platen 10 to the forward path 72.

[0090] The forward path 72 transports the platen 10 backward to the transfer mechanism 87, transfer mechanism 88, or transfer mechanism 89. Which of the transfer mechanisms 87, 88, or 89 the platen 10 is transported to is determined by which of the post-processing devices 6A, 6B, 6C, 6D, 6E, or 6F performs the post-processing. For example, let's explain the case where post-processing is performed by the post-processing device 6A. In this case, the platen 10 is transported to the transfer mechanism 87 and handed over from the forward path 72 to the transfer mechanism 87. The transfer mechanism 87 transports the platen 10 to the right and hands it over to the transport path of the post-processing device 6A (not shown).

[0091] The post-processing device 6A performs post-processing. Once post-processing by the post-processing device 6A is complete, the transport path of the post-processing device 6A (not shown) transports the platen 10 to the left and hands it over to the transfer mechanism 87. The transfer mechanism 87 hands the platen 10 over to the outbound path 72.

[0092] The outbound leg 72 transports the platen 10 backward and hands it over to the elevator mechanism 75. The elevator mechanism 75 descends to the same height as the return leg (not shown). The elevator mechanism 75 transports the platen 10 forward and hands it over to the return leg. The return leg, with the elevator mechanism 74 positioned at the same height as the return leg, transports the platen 10 forward and hands it over to the elevator mechanism 74.

[0093] The user removes the printed fabric F from the platen 10 while the platen 10 is being transported from elevator mechanism 75 to elevator mechanism 74 via the return path. For example, the user removes the printed fabric F from the platen 10 while the platen 10 is positioned on elevator mechanism 75. Then, with the platen 10 positioned on elevator mechanism 74, the user attaches the next fabric F to the platen 10. The same operation by the printing system 1 is repeated thereafter.

[0094] Referring to Figure 2, the electrical configuration of the drying apparatus 9 will be described. The drying apparatus 9 is a unit that includes a control device 90, a gas oven 4A, and a heat press device 5A. The control device 90 includes a CPU 91, flash memory 92, and RAM 93.

[0095] The CPU 91 controls the drying apparatus 9. The CPU 91 functions as a processor. The CPU 91 is electrically connected to the flash memory 92 and the RAM 93.

[0096] Flash memory 92 is a non-volatile storage medium. Flash memory 92 stores various types of information. For example, programs are stored in flash memory 92.

[0097] The program consists of computer-readable instructions. The program is executed by the CPU 91. When the program is executed by the CPU 91, it instructs the CPU 91 to perform various processes. The program includes a control program for executing the main process, which is shown in Figure 13 and described later.

[0098] RAM93 is a volatile storage medium. RAM93 temporarily stores various types of information. This information includes information calculated, acquired, identified, determined, received, or accepted during the main processing.

[0099] The CPU 91 is electrically connected to the gas burner 441, fan motor 451, and temperature sensor 46 of the gas oven 4A via the input / output interface 99. The gas burner 441 generates heat under the control of the CPU 91. The fan motor 451 is driven under the control of the CPU 91.

[0100] The temperature sensor 46 detects the ambient temperature inside the gas oven 4A. The temperature sensor 46 outputs a signal indicating the detected temperature to the CPU 91. The CPU 91 controls the heating temperature of the gas burner 441 based on the signal from the temperature sensor 46.

[0101] Furthermore, the CPU 91 is electrically connected to the heat-generating resistor 521, pressure control valve 511, and temperature sensor 54 of the heat press device 5A via the input / output interface 99. The heat-generating resistor 521 generates heat under the control of the CPU 91. The pressure control valve 511 adjusts the magnitude of the press pressure from the press section 51 under the control of the CPU 91.

[0102] The temperature sensor 54 detects the temperature of the press section 51. The temperature sensor 54 outputs a signal indicating the detected temperature to the CPU 91. The CPU 91 controls the heating temperature of the heat-generating resistor 521 based on the signal from the temperature sensor 54.

[0103] In this embodiment, gas ovens 4B, 4C, and 4D each have the same electrical configuration as gas oven 4A. Heat press device 5B has the same electrical configuration as heat press device 5A. Therefore, gas ovens 4B, 4C, 4D, and heat press device 5B are electrically connected to the CPU 91 via the input / output interface 99, just as gas oven 4A and heat press device 5A are electrically connected to the CPU 91 via the input / output interface 99.

[0104] Furthermore, printers 2A to 2D may be electrically connected to the CPU 91. A coating device 3A may be electrically connected to the CPU 91. Post-processing devices 6A to 6F may be electrically connected to the CPU 91. A transport device 7 may be electrically connected to the CPU 91. For example, if the transport device 7 is electrically connected to the CPU 91, the CPU 91 may control each motor of the transport device 7.

[0105] This section describes the details of white ink. White ink contains white pigment. White pigment is a white coloring agent. White pigment may be hollow particles or non-hollow particles. White pigment may contain both hollow and non-hollow particles.

[0106] Hollow particles include, for example, "SX-866(B)" (styrene-acrylic dispersion, 20% by weight pigment solids, primary particle size 0.3 μm) or "SX-868(B)" (styrene-acrylic dispersion, 20% by weight pigment solids, primary particle size 0.5 μm) from JSR Corporation, "ROPAQUE® ULTRA E" (styrene-acrylic dispersion, 30% by weight pigment solids, primary particle size 0.4 μm) from Rohm & Haas, or "NIPOL® V1004" (modified styrene-butadiene dispersion, 50% by weight pigment solids, primary particle size 0.3 μm), "NIPOL® MH8055" (styrene-acrylic dispersion, 30% by weight pigment solids, primary particle size 0.8 μm) or "NIPOL®" from Nippon Zeon Co., Ltd. MH5055 (styrene-acrylic dispersion, pigment solid content 30% by weight, primary particle size 0.5 μm) may also be used. Note that the primary particle size represents the volume-average particle size.

[0107] Non-hollow particles may include, for example, titanium dioxide, silicon dioxide, zinc oxide, aluminum oxide, magnesium oxide, barium sulfate, calcium carbonate, and the like.

[0108] The white ink may further contain, for example, a polymeric dispersant obtained by neutralizing an anionic water-soluble resin with a basic compound. The anionic water-soluble resin is, for example, a copolymer obtained by reacting one or more carboxyl group-containing unsaturated monomers with a mixture of one or more unsaturated monomers.

[0109] Examples of carboxyl group-containing unsaturated monomers include acrylic acid, methacrylic acid, itaconic acid, maleic acid, maleic anhydride, maleic acid monoalkyl ester, citraconic acid, citraconic anhydride, or citraconic acid monoalkyl ester. Note that carboxyl group-containing unsaturated monomers also include acid anhydride group-containing unsaturated monomers that yield a carboxyl group upon ring opening.

[0110] Unsaturated monomers include, for example, styrene monomers, aralkyl methacrylates, alkyl methacrylates, or acrylates. Styrene monomers include, for example, styrene, α-methylstyrene, or vinyltoluene. Aalkyl methacrylates include, for example, benzyl methacrylate or benzyl acrylate. Alkyl methacrylates include, for example, acrylates, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, methyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, or lauryl acrylate.

[0111] Basic compounds are, for example, alkali metal hydroxides or organic basic compounds. Alkali metal hydroxides are, for example, sodium hydroxide or potassium hydroxide. Organic basic compounds are, for example, triethylamine, monoethanolamine, triethanolamine, or triethylenediamine.

[0112] The amount of polymeric dispersant used is, for example, 10 to 40 parts by weight per 100 parts by weight of white pigment. The amount of polymeric dispersant used is, for example, 15 to 30 parts by weight per 100 parts by weight of white pigment.

[0113] In the total amount of white ink, the total solid content, including white pigment, polymer dispersant, resin component, nonionic resin emulsion, and anionic resin emulsion, is, for example, 25% to 45% by weight.

[0114] The white ink may contain, for example, humectants, surfactants, pH adjusters, viscosity modifiers, surface tension modifiers, preservatives, or antifungal agents. Humectants contribute, for example, to preventing the white ink from drying out. Examples of humectants include keto alcohols, polyalkylene glycols, polyhydric alcohols, 2-pyrrolidone, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone. An example of a keto alcohol is diacetone alcohol. An example of a polyhydric alcohol is alkylene glycol, glycerin, or trimethylolpropane.

[0115] Polyalkylene glycols are, for example, polyethylene glycol or polypropylene glycol. Alkylene glycols are, for example, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, thiodiglycol, or hexylene glycol.

[0116] The humectant may be of one type or two or more types. The humectant is preferably a polyhydric alcohol. The humectant content in the total amount of white ink is, for example, 0% to 60% by weight. The humectant content in the total amount of white ink is, for example, 3% to 50% by weight.

[0117] Surfactants contribute, for example, to adjusting the surface tension of white ink and improving the dispersibility of white pigment. There may be one type of surfactant or two or more types.

[0118] The details of the pretreatment solution are described below. The pretreatment solution contains a solvent component, a water-soluble component, a dispersion component, and an additive component. The solvent component is a component that is liquid at room temperature and evaporates during the drying process.

[0119] The solvent components include, for example, water and an organic solvent. Water improves the handling and storage stability of the pretreatment solution. The boiling point of the organic solvent is higher than that of water.

[0120] Examples of organic solvents include 1,3-propanediol, diglycerin, glycerin, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, hexylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,5-pentanediol, or 1,2,6-hexanetriol.

[0121] The water-soluble components include a flocculant and a surfactant. The flocculant causes the ink to aggregate and improves the color development of the ink. In this embodiment, high color development of the ink means that the ink develops vividly. For example, high color development of white ink means that L * a * b * L in color space * It means the value is high.

[0122] The flocculant is a polyvalent metal salt. Examples of polyvalent metal salts include calcium salts, magnesium salts, or aluminum salts.

[0123] Calcium salts include, for example, calcium chloride, calcium bromide, calcium iodide, calcium nitrite, calcium nitrate, calcium dihydrogen phosphate, calcium thiocyanate, calcium acetate, calcium lactate, calcium fumarate, or calcium citrate. Calcium salts may also be hydrates of, for example, calcium chloride, calcium bromide, calcium iodide, calcium nitrite, calcium nitrate, calcium dihydrogen phosphate, calcium thiocyanate, calcium acetate, calcium lactate, calcium fumarate, or calcium citrate.

[0124] Magnesium salts include, for example, magnesium chloride, magnesium bromide, magnesium iodide, magnesium sulfate, magnesium acetate, or magnesium nitrate. The magnesium salt may also be, for example, a hydrate of magnesium chloride, magnesium bromide, magnesium iodide, magnesium sulfate, magnesium acetate, or magnesium nitrate.

[0125] Aluminum salts include, for example, aluminum chloride, aluminum bromide, aluminum sulfate, aluminum nitrate, or aluminum acetate. The aluminum salt may also be, for example, a hydrate of aluminum chloride, aluminum bromide, aluminum sulfate, aluminum nitrate, or aluminum acetate.

[0126] A polyvalent metal salt may contain one type of polyvalent metal salt. A polyvalent metal salt may contain two or more types of polyvalent metal salts.

[0127] For example, from the viewpoint of suppressing discoloration of the fabric F due to pretreatment, it is preferable that the polyvalent metal salt contains a calcium salt, a magnesium salt, or both a calcium salt and a magnesium salt. For example, from the viewpoint of color development of the image printed by the printing process and cost, it is preferable that the polyvalent metal salt contains a calcium salt.

[0128] The surfactant is, for example, a nonionic surfactant. Nonionic surfactants are, for example, acetylene glycol-based surfactants. Nonionic surfactants may also be commercially available products. Examples of commercially available products include "Orphin® E1004", "Orphin® E1006", "Orphin® E1010", "Orphin® E1020", "Orphin® EXP4001", "Orphin® EXP4200", "Orphin® EXP4123", "Orphin® EXP4300", "Orphin® PD-001", "Orphin® PD-002W", "Orphin® PD-005", "Surfinol® 420", "Surfinol® 440", "Surfinol® 465", or "Surfinol® 485" manufactured by Nisshin Chemical Industry Co., Ltd.

[0129] The surfactant may include, in place of, or in addition to a nonionic surfactant, a surfactant other than a nonionic surfactant. Examples of surfactants other than nonionic surfactants include anionic surfactants, cationic surfactants, or amphoteric surfactants.

[0130] The dispersion component includes a resin component. The resin component is an aqueous resin. Examples of aqueous resins include acrylic acid resins, maleic acid ester resins, vinyl acetate resins, carbonate-type resins, polycarbonate-type resins, styrene-type resins, ethylene-type resins, polyethylene-type resins, propylene-type resins, polypropylene-type resins, urethane-type resins, or polyurethane-type resins. The aqueous resin may also be a copolymer resin of, for example, acrylic acid resins, maleic acid ester resins, vinyl acetate resins, carbonate-type resins, polycarbonate-type resins, styrene-type resins, ethylene-type resins, polyethylene-type resins, propylene-type resins, polypropylene-type resins, urethane-type resins, or polyurethane-type resins.

[0131] The water-based resin may be a commercially available product, for example. Examples of commercially available products include "Movinyl® 6770", "Movinyl® 7320", "Movinyl® 966A", "Movinyl® 6963", or "Movinyl® 6960" manufactured by Japan Coating Resin Co., Ltd., or "Viniblan® GV-6181" or "Viniblan® GV-1002" manufactured by Nisshin Chemical Industry Co., Ltd., or "Boncoat® SFC-55" or "Boncoat® SFC-571" manufactured by DIC Corporation.

[0132] The dispersion component may contain one type of aqueous resin. The dispersion component may contain two or more types of aqueous resins.

[0133] The additive components include, for example, crosslinking agents, pH adjusters, viscosity modifiers, preservatives, or fungicides. For example, preservatives suppress the growth of mold in the pretreatment solution and prevent the pretreatment solution from corroding.

[0134] Furthermore, among the additive components, those that are liquid at room temperature and evaporate during the drying process are classified as solvent components. Additive components that are solvent components are also called "additives equivalent to solvent components." Examples of additives equivalent to solvent components include room-temperature liquids added as pH adjusters. Examples of room-temperature liquids added as pH adjusters include water contained in hydrochloric acid or ammonia water.

[0135] Furthermore, among the various components exemplified above, the pretreatment solution should preferably contain at least a solvent component, a flocculant, and a resin component.

[0136] Referring to Figure 3, the behavior of the flocculant S2 during the drying process will be explained. As shown in state ST11, before the drying process, the pretreatment liquid S is applied to the fabric F by the coating process. In this state, the concentration of the flocculant S2 in the upper half of the pretreatment liquid S is about the same as the concentration of the flocculant S2 in the lower half of the pretreatment liquid S.

[0137] As shown in state ST12, during the drying process, the solvent component S1 in the pretreatment liquid S evaporates, and the flocculant S2 moves upward through the solvent component S1. As a result, as shown in state ST13, after the drying process, the flocculant S2 concentrates in the upper part of the pretreatment liquid S on the surface of the fabric F. In other words, after the drying process, the concentration of flocculant S2 in the upper half of the pretreatment liquid S becomes higher than the concentration of flocculant S2 in the lower half of the pretreatment liquid S.

[0138] As a result, during subsequent printing and post-processing, the white ink is more easily aggregated on the surface of the fabric F by the coagulant S2. Therefore, the drying process contributes to the vivid color development of the white ink.

[0139] Referring to Figure 4, the behavior of resin component S3 during the drying process will be explained. As shown in state ST21, before the drying process, the pretreatment liquid S is applied to the fabric F by the coating process. As shown in state ST22, during the drying process, the solvent component S1 in the pretreatment liquid S evaporates. In this case, the amount of transfer of resin component S3 is less than the amount of transfer of the flocculant S2 shown in Figure 3.

[0140] Therefore, as shown in state ST23, if the amount of evaporation of solvent component S1 during the drying process is constant, the resin component S3 tends to remain on the surface of the fabric F and easily forms a film. In this case, when subsequent printing and post-processing are performed, the penetration of white ink into the interior of the fabric F is suppressed by the resin component S3 that has formed a film on the surface of the fabric F. Thus, when the amount of evaporation of solvent component S1 is constant, the drying process contributes to the vivid color development of the white ink compared to when the amount of evaporation of solvent component S1 exceeds a constant amount.

[0141] As shown in state ST24, when the amount of evaporation of solvent component S1 during the drying process exceeds a certain amount, the resin component S3 tends to soften. When the resin component S3 softens, it tends to penetrate into the fabric F. As a result, when subsequent printing and post-processing are performed, the penetration of white ink into the interior of the fabric F is not easily suppressed by the resin component S3. Therefore, when the amount of evaporation of solvent component S1 exceeds a certain amount, the surface fibers of the fabric F are more easily exposed from the white ink applied to the fabric F compared to when the amount of evaporation of solvent component S1 is constant. For this reason, when the amount of evaporation of solvent component S1 exceeds a certain amount, the drying process does not contribute as much to the vivid color development of the white ink as it does to when the amount of evaporation of solvent component S1 is constant.

[0142] In this embodiment, when the amount of evaporation of solvent component S1 is a certain amount, it means that a small amount of solvent component S1 remains. A small amount of solvent component S1 remaining means that the target drying rate, as described later, falls within the range of 85% to 95%. When the amount of evaporation of solvent component S1 exceeds a certain amount, it means that substantially all of the solvent component S1 has evaporated. A substantially all of the solvent component S1 has evaporated means that the target drying rate exceeds 95%.

[0143] Referring to Figure 5, the effect of the amount of evaporation of solvent component S1 during the drying process on the color development of the white ink is explained. State ST31 shows the case where the amount of evaporation of solvent component S1 during the drying process is less than a certain amount. Therefore, in state ST31, the coagulant S2 is not concentrated in the upper part of the pretreatment liquid S.

[0144] In this case, when printing is performed afterward, the white ink is less likely to aggregate, as shown in state ST32. Therefore, the thickness of the white ink layer L1 becomes thinner compared to the thickness of the white ink layer L1 in states ST42 and ST52 described later. As a result, the color development of the white ink is worse than that of the white ink in states ST42 and ST52.

[0145] State ST41 represents the case where the amount of evaporation of solvent component S1 during the drying process is constant. Therefore, in state ST41, the flocculant S2 is concentrated on the upper part of the pretreatment liquid S, and the resin component S3 forms a film on the surface of the fabric F.

[0146] In this case, if printing is performed afterward, the white ink is prone to agglomeration, as shown in state ST42. Therefore, the thickness of the white ink layer L1 becomes thicker than the thickness of the white ink layer L1 in state ST32. Furthermore, the resin component S3 suppresses the penetration of the white ink layer L1 into the fabric F. As a result, the color development of the white ink is improved compared to the color development of the white ink in state ST32.

[0147] State ST51 represents the case where the amount of evaporation of solvent component S1 during the drying process exceeds a certain amount. Therefore, in state ST51, the flocculant S2 is concentrated in the upper part of the pretreatment liquid S, and the resin component S3 has penetrated into the fabric F.

[0148] In this case, if printing is performed afterward, the white ink is prone to agglomeration, as shown in state ST52. Therefore, the thickness of the white ink layer L1 becomes thicker than the thickness of the white ink layer L1 in state ST32. On the other hand, the effect of the resin component S3 in suppressing the penetration of the white ink layer L1 into the fabric F is reduced compared to state ST42, so the white ink layer L1 sinks into the fabric F. As a result, the surface fibers of the fabric F are more likely to be exposed from the white ink layer L1. Therefore, the color development of the white ink is improved compared to the color development of the white ink in state ST32, but it is reduced compared to the color development of the white ink in state ST42.

[0149] Referring to Figure 6, the coated area A1 and the uncoated area A2 are defined. The coated area A1 is the area of ​​the fabric F to which the pretreatment solution is applied by the coating process. The uncoated area A2 is the area of ​​the fabric F other than the coated area A1. In other words, the uncoated area A2 is the area of ​​the fabric F to which the pretreatment solution is not applied by the coating process.

[0150] Furthermore, if the fabric F has a tubular shape like a T-shirt, the uncoated area A2 is the area on the outer surface of the fabric F that is not coated with the pretreatment liquid during the coating process. For example, the front surface of the fabric F is the surface facing the coated area 31 during the coating process. The back surface of the fabric F is, for example, the surface on the outer surface of the fabric F that is opposite to the front surface.

[0151] The pretreatment solution is applied to the front surface of the fabric F by the coating unit 31. Therefore, the coating area A1 is included in the front surface of the fabric F.

[0152] Furthermore, the pretreatment solution applied to the front surface of fabric F may penetrate to the back surface of fabric F. In this case, the area of ​​the back surface of fabric F to which the pretreatment solution penetrates also falls under the category of application area A1. Therefore, application area A1 is also included on the back surface of fabric F. The size of application area A1 on the front surface of fabric F and the size of application area A1 on the back surface of fabric F may be the same or different.

[0153] In this embodiment, even if the fabric F is wetted by the pretreatment solution through penetration, the pretreatment solution is applied to the fabric F.

[0154] The target drying rate is defined below. In the following, the weight of moisture contained in the coated area A1 of the fabric F before the pretreatment solution is applied to the fabric F is referred to as the "initial moisture weight of the coated area A1". In this embodiment, the time before the pretreatment solution is applied to the fabric F refers to the time before the coating process. The initial moisture weight of the coated area A1 represents the weight of moisture that the coated area A1 of the fabric F has absorbed from the air in advance.

[0155] The weight of the solvent component contained in the pretreatment solution applied to the fabric F after the coating process but before the drying process is called the "initial solvent weight." In this embodiment, the time before the drying process refers to the time before the primary drying process. If the pretreatment solution contains an additive equivalent to the solvent component, the weight of the additive equivalent to the solvent component is also included in the weight of the solvent component.

[0156] The weight representing the sum of the initial solvent weight and the initial water weight of the coated area A1 is called the "weight of the target liquid." The amount by which the weight of the coated area A1 of the fabric F changes due to the drying process is called the "amount of change in the weight of the coated area A1." The amount of change in the weight of the coated area A1 is the amount obtained by subtracting the weight of the coated area A1 at the end of the secondary drying process from the weight of the coated area A1 at the start of the primary drying process.

[0157] The target drying rate represents the ratio of the change in the coated area A1 to the weight of the target liquid. Therefore, the target drying rate can be expressed mathematically as shown in Equation 1 below.

[0158] Target drying rate = Target change in coating area A1 / Weight of target liquid ... (Equation 1)

[0159] In the following, the amount by which the total weight of fabric F changes due to the drying process is referred to as the "target change in fabric F". The total weight of fabric F at the start of the primary drying process is referred to as the "weight of fabric F after coating treatment". The total weight of fabric F at the end of the secondary drying process is referred to as the "weight of fabric F after secondary drying treatment". The target change in fabric F is the amount obtained by subtracting the weight of fabric F after secondary drying treatment from the weight of fabric F after coating treatment. Therefore, the target change in fabric F can be expressed mathematically as shown in Equation 2 below.

[0160] Change in the weight of fabric F = Weight of fabric F after coating treatment - Weight of fabric F after secondary drying treatment ... (Equation 2)

[0161] The change in the coated area A1 is equal to the change in the fabric F minus the initial moisture weight of the uncoated area A2. Therefore, Equation 1 is transformed into Equation 3 below.

[0162] Target drying rate = (Target change in fabric F - Initial moisture weight of uncoated area A2) / (Initial solvent weight + Initial moisture weight of coated area A1) ... (Equation 3)

[0163] The primary drying rate is defined. The amount by which the weight of the coated area A1 of the fabric F changes due to the primary drying treatment is called the "primary change in coated area A1". The primary change in coated area A1 is the amount obtained by subtracting the weight of coated area A1 at the end of the primary drying treatment from the weight of coated area A1 at the start of the primary drying treatment.

[0164] The primary drying rate represents the ratio of the primary change in the coated area A1 to the weight of the target liquid. Therefore, the primary drying rate can be expressed mathematically as shown in Equation 4 below.

[0165] Primary drying rate = Primary change in coated area A1 / Weight of the target liquid ... (Equation 4)

[0166] In the following, the amount by which the total weight of fabric F changes due to the primary drying treatment is referred to as the "primary change in fabric F." The total weight of fabric F at the end of the primary drying treatment is referred to as the "weight of fabric F after primary drying treatment." The primary change in fabric F is the amount obtained by subtracting the weight of fabric F after primary drying treatment from the weight of fabric F after coating treatment. Therefore, the primary change in fabric F can be expressed mathematically as shown in Equation 5 below.

[0167] Primary change in fabric F = Weight of fabric F after coating treatment - Weight of fabric F after primary drying treatment ... (Equation 5)

[0168] The weight of moisture contained in the uncoated area A2 of the fabric F before the pretreatment solution is applied to the fabric F is called the "initial moisture weight of the uncoated area A2." The initial moisture weight of the uncoated area A2 represents the weight of moisture that the uncoated area A2 of the fabric F has already absorbed from the air.

[0169] The first change in coated area A1 is equal to the amount obtained by subtracting the initial moisture weight of uncoated area A2 from the first change in fabric F. Therefore, equation 4 is transformed into equation 6 below.

[0170] Primary drying rate = (Primary change in fabric F - Initial moisture weight of uncoated area A2) / (Initial solvent weight + Initial moisture weight of coated area A1) ... (Equation 6)

[0171] In the following, the amount by which the weight of the coated area A1 of the fabric F changes due to the secondary drying treatment is referred to as the "secondary change in coated area A1." The secondary change in coated area A1 is the amount obtained by subtracting the weight of coated area A1 at the end of the secondary drying treatment from the weight of coated area A1 at the start of the secondary drying treatment.

[0172] In this embodiment, the change in the coated area A1 may not be equal to the sum of the primary change and the secondary change of the coated area A1. This is because the fabric F may absorb moisture from the air between the primary and secondary drying processes.

[0173] The initial moisture content of fabric F is defined below. In the following, the weight of water contained in the entire fabric F before the pretreatment solution is applied to fabric F is referred to as the "initial moisture weight of fabric F". The weight of fabric F before the pretreatment solution is applied to fabric F is referred to as the "initial weight of fabric F".

[0174] The initial weight of fabric F is the sum of the weight of fabric F without moisture and the initial moisture weight of fabric F. Therefore, the weight of fabric F without moisture is equal to the initial weight of fabric F minus the initial moisture weight of fabric F. Hereafter, the weight of fabric F without moisture will be referred to as the "weight of fabric F after drying."

[0175] The initial moisture content of fabric F represents the initial water weight of fabric F relative to the weight of fabric F after drying. Therefore, the initial moisture content of fabric F can be expressed mathematically as shown in Equation 7 below.

[0176] Initial moisture content of fabric F = Initial moisture weight of fabric F / Weight of fabric F after drying ... (Equation 7)

[0177] Furthermore, after drying, fabric F contains virtually no moisture.

[0178] The initial moisture weight of the coated area A1 is calculated by the following equation 8, regardless of the size of the fabric F.

[0179] Initial moisture weight of coated area A1 = Initial weight of fabric F × Initial moisture content of fabric F × Area of ​​coated area A1 / Area of ​​fabric F ... (Equation 8)

[0180] The initial moisture weight of the uncoated area A2 is calculated by the following equation 9, regardless of the size of the fabric F.

[0181] Initial moisture weight of uncoated area A2 = Initial weight of fabric F × Initial moisture content of fabric F × Area of ​​uncoated area A2 / Area of ​​fabric F ... (Equation 9)

[0182] The area of ​​fabric F is equal to the sum of the area of ​​coated area A1 and the area of ​​uncoated area A2.

[0183] Referring to Figure 7, the moisture content measurement test for determining the initial moisture content of fabric F is described. The type of fabric F used in the moisture content measurement test is the same as the type of fabric F used in the drying rate measurement test described later.

[0184] First, measure the initial weight of fabric F. In the example in Figure 7, the initial weight of fabric F is 207.4g. Next, dry fabric F in an oven until its weight no longer changes substantially. An example of an oven is a gas oven 4A. For example, if the size of fabric F is about 50cm square, it is appropriate to dry fabric F in a gas oven 4A at 160°C for about 120 seconds.

[0185] The weight of fabric F after drying is measured. In the example in Figure 7, the weight of fabric F after drying is 191.8g. The weight obtained by subtracting the weight of fabric F after drying from the initial weight of fabric F is equal to the initial moisture weight of fabric F. Therefore, in the example in Figure 7, the initial moisture weight of fabric F is calculated as follows.

[0186] Initial moisture content of fabric F = 207.4-191.8 = 15.6g

[0187] Using equation 7 above, the initial moisture content of fabric F is calculated as follows.

[0188] Initial moisture content of fabric F = 15.6 / 191.8 =8.1%

[0189] Referring to Figure 8, the drying rate measurement test for determining the primary drying rate and the target drying rate will be explained. It is preferable that the drying rate measurement test be conducted on the same day as the moisture content measurement test. In this case, the temperature and humidity of the test site will be the same for both the moisture content measurement test and the drying rate measurement test. Therefore, it is assumed that the initial moisture content of the fabric F used in the moisture content measurement test and the fabric F used in the drying rate measurement test are substantially the same. In the drying rate measurement test, the fabric F is subjected to coating treatment, primary drying treatment, and secondary drying treatment in the order of coating treatment, primary drying treatment, and secondary drying treatment.

[0190] The composition of the pretreatment solution used in the drying rate measurement test is described below. The pretreatment solution contains a polyvalent metal salt, a resin component, a solvent component, a surfactant, and a preservative. The pretreatment solution contains 18% by mass of calcium nitrate tetrahydrate as the polyvalent metal salt. The pretreatment solution contains 6.8% by mass of aqueous resin as the resin component. The aqueous resin is Movinyl 6941.

[0191] The pretreatment solution contains water and an organic solvent as solvent components. The pretreatment solution contains 15% by mass of diglycerin as the organic solvent. The pretreatment solution contains % by mass of Olphine® EXP4123 as a surfactant. The pretreatment solution contains % by mass of Proxel® GXL(S) as a preservative.

[0192] The mass percentage of water represents the remainder of the pretreatment solution after the polyvalent metal salts, resin components, organic solvents, surfactants, and preservatives have been removed. The dilution ratio with water is ×3 vol%.

[0193] The following describes the equipment used in the drying rate measurement test. The coating device 3A was the The Cube2 manufactured by PRINT SYSTEM. The gas oven 4A was the PRO-CURE manufactured by ADELCO and the DDC-3A Drawer Drying Cabinet also manufactured by ADELCO. The heat press device 5A was the AIR FUSION IQ (registered trademark) manufactured by STAHLS' Hotronix.

[0194] The following describes how to determine the primary drying rate and target drying rate for Example 1. The primary drying rate and target drying rate can be determined for Examples 2-8 and Comparative Examples 1 and 2 in the same manner as in Example 1. Figure 8 is based on the moisture content measurement results shown in Figure 7.

[0195] First, the weight of fabric F in Example 1, that is, the initial weight of fabric F in Example 1, is measured. Fabric F used in the drying rate measurement test is of the same type as fabric F used in the moisture content measurement test, but it is a different fabric F. Therefore, the initial weight of fabric F used in the drying rate measurement test may differ from the initial weight of fabric F used in the moisture content measurement test. The initial weights of fabric F in Examples 2-8 and Comparative Examples 1 and 2 may also differ from the initial weight of fabric F in Example 1. In the example in Figure 8, the initial weight of fabric F in Example 1 is 208.7g.

[0196] In the example shown in Figure 8, the ratio of the area of ​​the coated region A1 to the area of ​​the fabric F is 39.8%. In this case, according to Equation 8, the initial water weight of the coated region A1 in Example 1 is calculated as follows, using the initial water content of the fabric F of 8.1%.

[0197] Initial moisture weight of coated area A1 in Example 1 = 208.7 × 8.1% × 39.8% = 6.7g

[0198] According to Equation 9, the initial moisture weight of the uncoated area A2 in Example 1 is calculated as follows, using the initial moisture content of the fabric F of 8.1%.

[0199] Initial moisture weight of uncoated area A2 in Example 1 = 208.7 × 8.1% × (100.0% - 39.8%) = 10.2g

[0200] Next, the fabric F from Example 1 was coated using the coating apparatus 3A. In the coating process, 42.4 g of pretreatment solution was applied to the fabric F per 14 × 16 inches.

[0201] Once the coating process is complete, the weight of the fabric F in Example 1 is measured. The amount of pretreatment solution applied during the coating process is the amount obtained by subtracting the initial weight of the fabric F from the weight of the fabric F after the coating process. In the example in Figure 8, the weight of the fabric F in Example 1 after the coating process is 267.4 g. Therefore, in the example in Figure 8, the amount of pretreatment solution applied during the coating process is calculated as follows.

[0202] Application amount of pretreatment solution in Example 1 = 267.4-208.7 = 58.7g

[0203] The initial solvent weight is the amount of pretreatment solution applied during the coating process multiplied by the mass concentration of the solvent component in the pretreatment solution. In the example in Figure 8, the mass concentration of the solvent component in the pretreatment solution is 90.7%. 90.7% is the ratio of the total weight of water and diglycerin to the total weight of the pretreatment solution. In the example in Figure 8, the initial solvent weight is calculated as follows.

[0204] Initial solvent weight in Example 1 = 58.7 × 90.7% = 53.2g

[0205] Next, the fabric F from Example 1 is subjected to a primary drying treatment in gas oven 4A. After the primary drying treatment is completed, the weight of the fabric F from Example 1 is measured. In the example shown in Figure 8, the weight of the fabric F from Example 1 after the primary drying treatment is 209.7 g.

[0206] The first-order change of fabric F in Example 1 is calculated using Equation 5 as follows.

[0207] The primary change in fabric F in Example 1 = 267.4 - 209.7 = 57.7g

[0208] Therefore, the primary drying rate in Example 1 is calculated using Equation 6 as follows.

[0209] Primary drying rate for Example 1 = (58.7 - 10.2) / (53.2 + 6.7) =79.3%

[0210] Next, the fabric F of Example 1 is subjected to a secondary drying process in the heat press apparatus 5A. After the secondary drying process is completed, the weight of the fabric F of Example 1 is measured. In the example shown in Figure 8, the weight of the fabric F of Example 1 after the secondary drying process is 206.1 g.

[0211] The change in the fabric F in Example 1 is calculated using Equation 2 as follows.

[0212] Target change in fabric F in Example 1 = 267.4 - 206.1 = 61.3g

[0213] Therefore, the target drying rate for Example 1 is calculated using Equation 3 as follows.

[0214] Target drying rate for Example 1 = (61.3 - 10.2) / (53.2 + 6.7) =85.3%

[0215] Similarly, the primary drying rate and target drying rate for Examples 2-8 and Comparative Examples 1 and 2 are calculated. For Examples 2-8 and Comparative Examples 1 and 2, only the calculation results are shown in Figure 9.

[0216] In Examples 1 to 8 and Comparative Examples 1 and 2, the processing conditions of the primary drying process are different. The processing conditions of the primary drying process are, for example, the heating temperature of the heater 44 or the driving time of the heater 44 and the fan 45. For each of Examples 1 to 8 and Comparative Examples 1 and 2, the processing conditions of the secondary drying process are the same. The processing conditions of the secondary drying process are, for example, the heat generation temperature of the heater 52, the pressurization time by the press section 51, and the magnitude of the pressurization by the press section 51.

[0217] Relationship between the primary drying rate and the target L * value, and the relationship between the target drying rate and the target L * An evaluation test was conducted to obtain the relationship with the value. For the target L * In the evaluation test for evaluating the value, printing processing was performed with the printer 2A for each of Examples 1 to 8 and Comparative Examples 1 and 2 shown in FIG. 9. In the printing process, white ink was used.

[0218] GCX-4W manufactured by Brother Industries, Ltd. was used as the white ink.

[0219] Target L * The equipment used in the evaluation test for evaluating the value will be described. GTX-pro manufactured by Brother Industries, Ltd. was used for the printer 2A. For the target L * X-Rite (registered trademark) eXact manufactured by X-Rite was used as the colorimeter for measuring the value.

[0220] Target L * The fabric F used in the evaluation test for evaluating the value will be described. In this case, the fabric F has a black color. The fabric F is 100% cotton. Specifically, the fabric F is GILDAN Ultra cotton Black manufactured by GILDAN.

[0221] Target L * The value is the L in the white ink layer formed on the fabric F in the printing process. * a * b * L in the color space * value. L *The value indicates the degree of whiteness. L * The higher the value, the higher the degree of whiteness.

[0222] In the evaluation test, target L * To evaluate the value, for each of Examples 1-8 and Comparative Examples 1 and 2, a colorimeter was used on the printed fabric F to measure the L of the white ink layer formed on the fabric F. * The values ​​were measured. Figure 9 shows the measured target L for each of Examples 1-8 and Comparative Examples 1 and 2. * The result is shown in terms of value.

[0223] Refer to Figures 9 to 11, target L * The results of the evaluation test for the values ​​will be explained. As shown in box R1 in Figure 9, Examples 1 to 8 are examples in which the target drying rate falls within the range of 82% or more and 95% or less. In this case, as shown by line L1 in Figures 9 and 10, the target L * All values ​​were 85 or higher. According to Japanese Patent Publication No. 2019-11527, L * The value is preferably 85 or higher.

[0224] On the other hand, as shown in box R2 in Figure 9, Comparative Examples 1 and 2 are examples where the target drying rate is less than 82%. More specifically, Comparative Examples 1 and 2 are examples where the target drying rate is 78% or less. In this case, as shown by line L1 in Figures 9 and 10, the target L * All values ​​were below 85. For details, see Target L * All values ​​were less than 84.

[0225] As shown in box R3 in Figure 9, Examples 1 to 6 are examples in which the primary drying rate falls within the range of 79% or more and 97% or less. In this case, the target drying rate fell within the range of 85% or more and 95%. Furthermore, as shown by line L2 in Figures 9 and 11, the target L * All values ​​were 86.2 or higher.

[0226] Generally, chromatic difference ΔE * If ab is 1.2 or greater, that is, the color difference ΔE *If ab is greater than or equal to the practical color difference a, a difference in color is observed. Specifically, the color difference ΔE * When two colors with ab values ​​of 1.2 or higher are placed side by side, most people can easily recognize the color difference. Therefore, L * If the value is 85 + 1.2, i.e., 86.2 or greater, L * Compared to a value of 85, the color development of the white ink improves to a degree that most people can easily perceive the color difference. In other words, when the primary drying rate is between 79% and 97%, the color development of the white ink improves to a degree that most people can easily perceive the color difference compared to when the primary drying rate is less than 79% or more than 97%.

[0227] Primary heat quantity and symmetric color difference ΔE * An evaluation test was conducted to determine the relationship with ab. Target color difference ΔE * This section describes the equipment used in the evaluation test to assess ab. Target color difference ΔE * The colorimeter used to measure ab was the X-Rite® eXact manufactured by X-Rite Corporation.

[0228] Target color difference ΔE * The fabric F used to evaluate ab is described below. Fabric F is white. Fabric F is 100% cotton. Specifically, Fabric F is GILDAN Ultra cotton White manufactured by GILDAN.

[0229] Target color difference ΔE * ab is the color difference ΔE between the fabric F before the primary drying treatment and the fabric F after the primary drying treatment, when the primary drying treatment is performed. * ab. Chromatic difference ΔE * ab indicates the difference in color. Color difference ΔE * The larger ab is, the greater the difference in color. For example, in JIS Z 8730, the color difference ΔE * ab = 1.2 is defined as the practical color difference a. The practical color difference a is the color difference that can be perceived by the human eye.

[0230] Target color difference ΔE* ab is calculated by the following equation 10.

[0231] Target color difference ΔE * ab={(L * 1-L * 2) 2 +(a * 1-a * 2) 2 +(b * 1-b * 2) 2} 1 / 2 ...Formula 10 (L * 1,a * 1,b * 1) is L in the fabric F before drying. * a * b * It is a color in the color space. (L * 2,a * 2,b * 2) is L in the fabric F after drying treatment. * a * b * It is a color in the color space.

[0232] In the evaluation test, the target color difference ΔE * To evaluate ab, L * a * b * The color space was measured. For each of Examples 1-8 and Comparative Examples 1 and 2, a colorimeter was used to measure the L of the uncoated area A2 of the fabric F before drying. * a * b * The color of the color space was measured. For each of Examples 1-8 and Comparative Examples 1 and 2, a colorimeter was used to measure the L of the uncoated area A2 of the fabric F after drying. * a * b * The color in the color space was measured. Using this, the above equation 10 was used to determine the target color difference ΔE * ab was calculated. Figure 9 shows the calculated target color difference ΔE for each of Examples 1-8 and Comparative Examples 1 and 2. * The results for ab are shown.

[0233] The primary heat quantity is the amount of heat that the fabric F coated with the pretreatment solution receives from the gas oven 4A during the primary drying treatment. For example, let's explain how to determine the primary heat quantity in Example 1. Under the same conditions as the primary drying treatment in Example 1, the primary drying treatment is performed in the gas oven 4A with water instead of fabric F.

[0234] Based on the change in water weight due to the primary drying process, the primary heat quantity is calculated using the following equation 11.

[0235] Primary heat amount = m×c×(T2-T1)+m×L (Formula 11) m is the change in the weight of water (g). c is the specific heat of water (J / g·K). The specific heat of water is 4.18 J / g·K. T1 is room temperature (°C). For example, if the ambient temperature of the room where the test was conducted was 25°C, then the room temperature is 25°C. T2 is the ambient temperature (°C) inside gas oven 4A during the primary drying process. Furthermore, assuming that the liquid water temperature only rises to 100°C, if T2 exceeds 100°C, T2 will be set to 100°C. L is the heat of vaporization of water (J / g). The heat of vaporization of water is 2260 J / g.

[0236] Figure 9 shows the calculated primary heat values ​​for each of Examples 1-8 and Comparative Examples 1 and 2.

[0237] Refer to Figures 9 and 12, and the target color difference ΔE * The results of the evaluation test for ab will be explained. As shown in box R4 in Figure 9, Examples 1 to 6 are examples in which the primary heat value falls within the range of 2500 J or more and 4100 J or less. In this case, as shown by line L3 in Figures 9 and 12, the target color difference ΔE * Both values ​​of ab were less than 1.2.

[0238] Generally, chromatic difference ΔE *If ab is less than 1.2, that is, the color difference ΔE * If ab is less than the practical color difference a, no difference in color is observed. Specifically, the color difference ΔE * If ab is less than 1.2, it is judged to be within an acceptable range by human perception. In other words, if the primary heat is within the range of 2500J or more and 4100J or less, the change in the color of fabric F due to the drying process is considered acceptable.

[0239] Referring to Figure 13, the main process will be explained. When power is turned on to the drying apparatus 9, the CPU 91 reads the control program from the flash memory 92 and executes the main process. In the main process, the CPU 91 controls the primary drying process and the secondary drying process.

[0240] The CPU 91 determines whether the platen 10 has reached any of the gas ovens 4A to 4D (S11) based on the position sensors of the gas ovens 4A to 4D (not shown). For example, the position sensor of gas oven 4A detects the platen 10 when it reaches gas oven 4A. The position sensor of gas oven 4A outputs information to the CPU 91 indicating the detected platen 10. If the platen 10 has not reached any of the gas ovens 4A to 4D (S11: NO), the CPU 91 proceeds to the decision in S21.

[0241] If the platen 10 reaches any of the gas ovens 4A to 4D (S11: YES), the CPU 91 starts the primary drying process in the gas oven to which the platen 10 has reached (S12). The following describes the case where the platen 10 reaches gas oven 4A. In this case, during the process in S12, the CPU 91 starts driving the gas burner 441 shown in Figure 2 and also starts driving the fan motor 451 shown in Figure 2.

[0242] The CPU 91 determines whether the primary calorific value has reached 2500 J or more and 4100 J or less (S13). In this embodiment, when the primary calorific value reaches 2500 J or more and 4100 J or less, the primary drying rate becomes 79% or more and 97% or less. Therefore, in the process of S13, the CPU 91 may determine whether the primary drying rate has reached 79% or more and 97% or less.

[0243] An example of the determination method in the process of S13 will be described. In the process of S13, the CPU 91 refers to the primary drying setting information 921 shown in FIG. 14.

[0244] As shown in FIG. 14, the primary drying setting information 921 indicates the processing conditions of the primary drying process. The primary drying setting information 921 is configured such that when the primary drying process is performed under the processing conditions indicated by the primary drying setting information 921, the primary calorific value becomes 2500 J or more and less than 4100 J. When the primary drying process is performed under the processing conditions indicated by the primary drying setting information 921, the primary drying setting information 921 is configured such that the primary drying rate becomes 79% or more and 97% or less. The primary drying setting information 921 is determined based on, for example, the conditions of the primary drying process in the above Examples 1 to 6.

[0245] In this embodiment, the processing conditions of the primary drying process include the heating temperature of the heater 44 and the drying time. In the primary drying setting information 921, "A1 °C" is defined as the heating temperature of the heater 44. In the primary drying setting information 921, "A2 seconds" is defined as the drying time. Therefore, when the primary drying process is performed for "A2 seconds" at "A1 °C", the primary calorific value becomes 2500 J or more and 4100 J or less, and the primary drying rate becomes 79% or more and 97% or less.

[0246] In the process of S13, the CPU 91 determines whether to execute the primary drying process at the heating temperature of the heater 44, "A1 °C", for the drying time, "A2 seconds", based on the primary drying setting information 921. If the primary drying process is executed at the heating temperature of the heater 44, "A1 °C", for the drying time, "A2 seconds", the CPU 91 determines that the primary heat quantity is 2500 J or more and 4100 J or less. If the primary drying process is executed at the heating temperature of the heater 44, "A1 °C", for the drying time, "A2 seconds", the CPU 91 determines that the primary drying rate is 79% or more and 97% or less.

[0247] If the primary drying process is not executed at the heating temperature of the heater 44, "A1 °C", for the drying time, "A2 seconds", the CPU 91 determines that the primary heat quantity has not reached 2500 J. If the primary drying process is not executed at the heating temperature of the heater 44, "A1 °C", for the drying time, "A2 seconds", the CPU 91 determines that the primary drying rate has not reached 79%.

[0248] When there are multiple types of the fabric F, the coating amount of the pretreatment liquid on the fabric F by the coating process may vary depending on the type of the fabric F. The heating temperature and the drying time may be determined in advance according to the coating amount of the pretreatment liquid, that is, the type of the fabric F. For example, a plurality of primary drying setting information 921 may be stored in the flash memory 92 for each type of the fabric F. In this case, the CPU 91 may acquire the type of the fabric F and refer to the primary drying setting information 921 corresponding to the acquired type of the fabric F. For example, the CPU 91 may acquire the type of the fabric F or the coating amount of the pretreatment liquid from the CPU of the coating device 3A.

[0249] As shown in FIG. 13, when the primary heat quantity has not reached 2500 J (S13: NO), the CPU 91 repeats the determination of S13. In the process of S13, when the primary drying rate has not reached 79% (S13: NO), the CPU 91 may repeat the determination of S13.

[0250] If the primary heat energy is between 2500J and 4100J (S13:YES), the CPU 91 terminates the primary drying process (S14). In the process of S13, if the primary drying rate is between 79% and 97% (S13:YES), the CPU 91 may terminate the primary drying process (S14). The CPU 91 then proceeds to the decision in S21.

[0251] The fabric F, whose primary drying rate has been reduced to 79% or more and 97% or less by the S14 process, is then transported by the conveying device 7 to either the heat press device 5A or 5B.

[0252] The CPU 91 determines whether the platen 10 has reached either the heat press device 5A or 5B based on the position sensors of the heat press devices 5A and 5B (not shown) (S21). For example, the position sensor of heat press device 5A detects the platen 10 when it reaches heat press device 5A. The position sensor of heat press device 5A outputs information to the CPU 91 indicating the detected platen 10. If the platen 10 has not reached either heat press device 5A or 5B (S21: NO), the CPU 91 returns to the decision in S11.

[0253] When the platen 10 reaches either the heat press device 5A or 5B (S21: YES), the CPU 91 starts the secondary drying process in the heat press device to which the platen 10 has reached (S22). The following describes the case when the platen 10 reaches the heat press device 5A. In this case, during the process in S22, the CPU 91 starts driving the heating resistor 521 shown in Figure 2 and also starts driving the pressure control valve 511 shown in Figure 2.

[0254] CPU91 determines whether the target drying rate is between 82% and 95% (S23).

[0255] An example of the decision-making method in the S23 process is described below. In the S23 process, the CPU 91 refers to the secondary drying setting information 922 shown in Figure 15.

[0256] As shown in Figure 15, the secondary drying setting information 922 indicates the processing conditions for the secondary drying process. The secondary drying setting information 922 is configured such that when the secondary drying process is performed under the processing conditions indicated by the secondary drying setting information 922, the target drying rate is 82% or more and 95% or less. The secondary drying setting information 922 is determined, for example, based on the conditions for the secondary drying process in the above examples 1 to 8.

[0257] In this embodiment, the processing conditions for the secondary drying process include the heating temperature of the heater 52, the pressing time, and the pressing pressure. In the secondary drying setting information 922, "B1°C" is set as the heating temperature of the heater 52. In the secondary drying setting information 922, "B2 seconds" is set as the pressing time. In the secondary drying setting information 922, "B3N / m" is set as the pressing pressure. 2 " is defined as "B1℃" and "B3N / m 2 If a secondary drying process is performed for "B2 seconds" using the command line, the target drying rate will be between 82% and 95%.

[0258] In the S23 process, the CPU 91 sets the heating temperature of the heater 52 to "B1℃" and the pressing pressure of the pressing section 51 to "B3N / m" based on the secondary drying setting information 922. 2 The system determines whether a secondary drying process was performed during a pressing time of "B2 seconds". The heating temperature of the heater 52 is "B1℃" and the pressing pressure of the pressing section 51 is "B3N / m". 2 If a secondary drying process is performed for a pressing time of "B2 seconds", the CPU 91 determines that the target drying rate is between 82% and 95%. Heating temperature of heater 52 "B1℃" and pressing pressure of press section 51 "B3N / m 2 If the secondary drying process is not performed during the pressing time of "B2 seconds", the CPU91 determines that the target drying rate has not reached 82%.

[0259] As shown in Figure 13, if the target drying rate has not reached 82% (S23: NO), the CPU 91 may repeat the decision in S23. If the target drying rate is 82% or more and 95% or less (S23: YES), the CPU 91 terminates the secondary drying process (S24). The CPU 91 returns to the decision in S11.

[0260] The main effects of this embodiment will be explained. According to the evaluation test results, when the target drying rate is 82% or more and 95% or less, target L * The value becomes 85 or higher. In this embodiment, the CPU 91 controls the gas oven 4A and the heat press device 5A to dry the fabric F to which the pretreatment liquid has been applied until the target drying rate is 82% or higher and 95% or lower (S24).

[0261] According to this, the fabric F will be sent to the printing process when the target drying rate is between 82% and 95%. Therefore, if white ink is applied to the fabric F during the printing process, target L * The value becomes 85 or higher. Therefore, the drying device 9 contributes to improving the color reproduction of the printed image.

[0262] In the primary drying process, the CPU 91 controls the gas oven 4A to dry the fabric F to which the pretreatment solution has been applied (S12, S14). After the primary drying process, the CPU 91 controls the heat press device 5A to dry the fabric F to which the pretreatment solution has been applied until the target drying rate is between 82% and 95% (S22, S24).

[0263] According to this, the fabric F is dried by the primary drying process before the secondary drying process. Therefore, the amount of fabric F dried in the secondary drying process is less compared to when the primary drying process is not performed. Thus, the drying device 9 contributes to making it easier to control the target drying rate between 82% and 95%.

[0264] In the heat press device 5A, when the fabric F is removed from the heat press device 5A, the press by the press unit 51 must be released. Therefore, it is difficult for the heat press device 5A to continuously dry multiple pieces of fabric F. On the other hand, the gas oven 4A can continuously load and unload fabric F. Therefore, the gas oven 4A is more efficient at improving production efficiency than the heat press device 5A.

[0265] In the primary drying process, the CPU 91 controls the gas oven 4A to dry the fabric F coated with the pretreatment liquid (S12, S14). In the secondary drying process, the CPU 91 controls the heat press device 5A to dry the fabric F coated with the pretreatment liquid (S22, S24).

[0266] According to this, after the drying device 9 dries the fabric F in a non-contact manner with higher production efficiency than the contact method, it dries the fabric F in a contact manner to lay down the surface fibers of the fabric F. When printing is performed with the surface fibers of the fabric F laid down, the quality of the printed image is improved compared to the case where printing is performed with the surface fibers of the fabric F standing up. Therefore, the drying device 9 contributes to improving the quality of the printed image while improving the production efficiency.

[0267] According to the evaluation test results, when the primary drying rate is 79% or more and 97% or less and then the target drying rate is 82% or more and 95% or less, the target L * value becomes 86.2 or more. In this embodiment, in the primary drying process, the CPU 91 dries the fabric F coated with the pretreatment liquid until the primary drying rate becomes 79% or more and 97% or less (S12, S14).

[0268] According to this, it becomes easier for the drying device 9 to control the target drying rate to approach the median value of 82% or more and 95% or less. For example, the target drying rate is likely to be between 85% and 93%. Therefore, when white ink is applied to the fabric F in the printing process, the target L * value is likely to become 86.2 or more. Therefore, the drying device 9 further contributes to improving the color development of the printed image.

[0269] According to the evaluation test results, when the primary heat quantity is 2500 J or more and 4100 J or less, the target color difference ΔE * ab becomes 1.2 or less. In this embodiment, in the primary drying process, the CPU 91 drives the gas oven 4A until the primary heat quantity becomes 2500 J or more and 4100 J or less (S12, S14).

[0270] According to this, the color difference ΔE* Fabric F with an ab value of 1.2 or less is sent to the secondary drying treatment and subsequent treatments. Therefore, the drying apparatus 9 contributes to drying the fabric F while suppressing discoloration of the fabric F during the primary drying treatment.

[0271] In the above embodiment, the gas ovens 4A to 4D and the heat press devices 5A and 5B correspond to the "drying section" of the present invention. The CPU 91 corresponds to the "control section" of the present invention. The processes S12 to S14 and S22 to S24 correspond to the "drying process" of the present invention. The drying device 9 corresponds to the "drying device" of the present invention.

[0272] Oven processing and primary drying processing correspond to the "primary drying processing" of the present invention. Heat pressing processing and secondary drying processing correspond to the "secondary drying processing" of the present invention. Gas ovens 4A to 4D correspond to the "non-contact drying section" of the present invention. Heat pressing devices 5A and 5B correspond to the "contact drying section" of the present invention.

[0273] The present invention may be modified in various ways from the above embodiments. The modifications described below may be combined with each other to the extent that they do not contradict each other.

[0274] In the above embodiment, the number of printers 2A to 2D may be changed from two. For example, the number of printers 2A to 2D may be one or three or more. Similarly, the number of coating devices 3A, gas ovens 4A to 4D, heat press devices 5A and 5B, and post-processing devices 6A to 6F may also be changed as appropriate.

[0275] In the above embodiment, the printing system 1 may omit components other than the drying device 9. For example, the printing system 1 may omit the transport device 7 and the post-processing device 6A, and instead include a coating device 3A, a printer 2A, a gas oven 4A, and a heat press device 5A.

[0276] In the above embodiment, the drying apparatus 9 may omit the gas ovens 4A to 4D. The drying apparatus 9 may also omit the heat press devices 5A and 5B.

[0277] In the above embodiment, the CPU 91 performs primary drying in gas ovens 4A to 4D and secondary drying in heat press devices 5A and 5B. Alternatively, the CPU 91 may perform primary drying in heat press devices 5A and 5B and secondary drying in gas ovens 4A to 4D.

[0278] CPU91 may perform primary drying in gas ovens 4A to 4D, and then perform secondary drying in gas ovens 4A to 4D. In this case, CPU91 may perform primary drying in a specific device among gas ovens 4A to 4D, and then continuously perform secondary drying in a specific device. CPU91 may perform primary drying in a specific device among gas ovens 4A to 4D, and then perform secondary drying in another device among gas ovens 4A to 4D.

[0279] The CPU 91 may perform a primary drying process using heat press devices 5A and 5B, and then perform a secondary drying process using the same heat press devices 5A and 5B. In this case, the CPU 91 may perform the primary drying process using a specific device among the heat press devices 5A and 5B, and then continuously perform the secondary drying process using another specific device. Alternatively, the CPU 91 may perform the primary drying process using a specific device among the heat press devices 5A and 5B, and then perform the secondary drying process using another device among the heat press devices 5A and 5B.

[0280] In the above embodiment, an electric oven may be used instead of the gas ovens 4A to 4D. A microwave oven may be used instead of the gas ovens 4A to 4D.

[0281] In the above embodiment, the heat press devices 5A and 5B may be mechanical, hydraulic, or servo-driven.

[0282] CPU91 may stop operating the gas oven 4A when the primary drying rate is less than 79% during the primary drying process. CPU91 may also stop operating the gas oven 4A when the primary drying rate exceeds 97% during the primary drying process.

[0283] The CPU 91 may stop operating the gas oven 4A when the primary heat output is less than 2500 J during the primary drying process. The CPU 91 may also stop operating the gas oven 4A when the primary heat output exceeds 4100 J during the primary drying process.

[0284] The control device 90 may be mounted on any of the devices included in the printing system 1, or it may be located outside of the devices included in the printing system 1. For example, the control device 90 may be mounted on the gas oven 4A, or it may be installed as a control panel.

[0285] Fabric F may be changed from 100% cotton. For example, Fabric F may be less than 100% cotton. Fabric F may also contain other natural fibers or synthetic fibers.

[0286] Instead of the CPU91, a microcomputer, ASIC (Application Specific Integrated Circuits), FPGA (Field Programmable Gate Array), etc., may be used as the processor. The main processing may be distributed among multiple processors.

[0287] Non-temporary storage media such as flash memory 92 can be any storage medium capable of retaining information regardless of the storage period. Non-temporary storage media do not necessarily have to include temporary storage media (e.g., transmitted signals). The control program may be downloaded, for example, from a server connected to a network (not shown), i.e., transmitted as a transmission signal, and stored in flash memory 92. In this case, the control program only needs to be stored on a non-temporary storage medium such as an HDD provided in the server. [Explanation of Symbols]

[0288] 1: Printing System 4A~4D: Gas oven 5A, 5B: Heat press equipment 9: Drying device 91: CPU

Claims

1. A drying section for drying the fabric to which a pretreatment solution has been applied before the ink containing the pigment is applied to the fabric, Control unit and Equipped with, The control unit, The drying section is controlled, and a drying process is performed to dry the fabric to which the pretreatment liquid has been applied until the target drying rate is 82% or more and 95% or less. The aforementioned target drying rate represents the ratio of the target change amount to the weight of the target liquid. The weight of the target liquid is the sum of the weight of the solvent component contained in the pretreatment solution applied to the fabric before the drying process and the weight of the water contained in the area of ​​the fabric to which the pretreatment solution is applied before the pretreatment solution is applied to the fabric. The aforementioned change in the target amount indicates the amount by which the weight of the region of the fabric changes due to the drying process. A drying apparatus characterized by the following.

2. The control unit, in the drying process, A primary drying process that controls the drying section and dries the fabric to which the pretreatment liquid has been applied, After the primary drying treatment, a secondary drying treatment is performed in which the drying section is controlled and the fabric to which the pretreatment liquid has been applied is dried until the target drying rate is 82% or more and 95% or less. The drying apparatus according to claim 1, characterized by performing the following.

3. The drying section is A non-contact drying unit for drying the fabric in a non-contact manner, A contact drying unit for drying the fabric by contact, and Includes, The control unit, In the aforementioned primary drying process, the non-contact drying section is controlled and the pretreatment liquid is applied. The aforementioned fabric is dried. In the secondary drying process, the contact drying section is controlled, and the pretreatment liquid is applied before To dry the fabric The drying apparatus according to claim 2, characterized by the following:

4. The control unit, In the primary drying process, the fabric to which the pretreatment liquid has been applied is dried until the primary drying rate is 79% or more and 97% or less. The primary drying rate indicates the ratio of the primary change to the weight of the target liquid. The aforementioned primary change amount indicates the amount by which the weight of the region of the fabric changes due to the primary drying treatment. The drying apparatus according to claim 2, characterized by the following:

5. The control unit, In the primary drying process, the non-contact drying unit is driven until the fabric to which the pretreatment liquid has been applied receives a heat energy of 2500 J or more and 4100 J or less. A drying apparatus according to claim 3, characterized by the following:

6. A drying method for controlling a drying apparatus equipped with a drying section for drying a fabric to which a pretreatment solution has been applied before an ink containing pigment is applied to the fabric, The system includes a drying process that controls the drying section and dries the fabric to which the pretreatment liquid has been applied until the target drying rate is 82% or more and 95% or less. The aforementioned target drying rate represents the ratio of the target change amount to the weight of the target liquid. The weight of the target liquid represents the sum of the weight of the solvent component contained in the pretreatment solution applied to the fabric before the drying process and the weight of the water contained in the area of ​​the fabric to which the pretreatment solution is applied before the pretreatment solution is applied to the fabric, and the target change represents the amount by which the weight of the area of ​​the fabric changes due to the drying process. A drying method characterized by the following.

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