Inkjet recording device

Abstract

An inkjet recording device includes a conveyor unit, a carriage, an inkjet head, and multiple processing heads. The conveyor unit transports the recording medium along a predetermined conveyor direction. The carriage reciprocates along a main scanning direction intersecting the conveyor direction. The inkjet heads are mounted on the carriage in an array along the main scanning direction and eject ink for image formation. The processing heads are mounted on the carriage and eject a non-coloring processing liquid. The multiple processing heads are positioned in the conveyor direction, different from the inkjet heads, and are arranged along the main scanning direction.

Description

Technical Field

[0001] The present invention relates to an inkjet recording device including an ink head mounted on a carriage that moves in a main scanning direction. Background Art

[0002] Inkjet recording devices such as inkjet printers include an ink head that ejects ink for image formation toward a recording medium. For example, when the recording medium is a fiber sheet such as a woven or knitted fabric, or a plastic sheet, it is sometimes necessary to apply a pre-treatment liquid and a post-treatment liquid to the recording medium before and after the ink is ejected onto the recording medium (e.g., Patent Document 1). The pre-treatment liquid is, for example, a treatment liquid used to improve the fixability of the ink to the recording medium and the cohesion of the ink pigment. The post-treatment liquid is, for example, a treatment liquid used to improve the firmness of the printed image. In this case, the inkjet recording device includes, in addition to the ink head, a treatment head that ejects the pre-treatment liquid and the post-treatment liquid.

[0003] When recording media is wide, the ink head and processing head are mounted on a carriage that reciprocates in the main scanning direction. During recording, the recording medium is intermittently transported in a predetermined transport direction (sub-scanning direction). When the recording medium is stopped, the carriage reciprocates in the main scanning direction. During this movement, the ink head and processing head eject ink and processing fluid, respectively.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Publication No. 2019-147307 Summary of the Invention

[0007] An inkjet recording device according to one aspect of the present invention includes a conveyor unit, a carriage, an inkjet head, and a plurality of processing heads. The conveyor unit conveys a recording medium along a predetermined conveyor direction. The carriage reciprocates along a main scanning direction intersecting the conveyor direction. The inkjet heads are mounted on the carriage in an aligned manner in the main scanning direction and eject ink for image formation. The processing heads are mounted on the carriage and eject a non-coloring processing liquid. The plurality of processing heads are arranged along the main scanning direction at positions different from the inkjet heads in the conveyor direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 It is a perspective view showing the overall structure of an inkjet printer according to one embodiment of the present invention.

[0009] Figure 2 yes Figure 1 Schematic cross-sectional view along line II-II.

[0010] Figure 3 yes Figure 1 An enlarged perspective view of the carriage is shown.

[0011] Figure 4 It is a schematic diagram showing the serial printing method adopted in this embodiment.

[0012] Figure 5A It is a schematic diagram showing the printing status of the carriage on the forward path and the backward path.

[0013] Figure 5B This is a schematic diagram showing the printing status of the carriage on the forward and return paths.

[0014] Figure 6 This is a top view schematically showing the head configuration of Example 1. Figure 3 The arrangement of the ink head and the processing head in the carriage is shown.

[0015] Figure 7 This is a plan view of a carriage showing the head arrangement according to the second embodiment.

[0016] Figure 8 This is a plan view of a carriage showing the head arrangement according to the third embodiment.

[0017] Figure 9 This is a top view of a carriage showing the head arrangement according to the fourth embodiment.

[0018] Figure 10 It is a top view of a carriage showing the head arrangement according to the fifth embodiment.

[0019] Figure 11 It is a top view of a carriage showing the head arrangement according to the sixth embodiment.

[0020] Figure 12 It is a top view of a carriage showing the head arrangement according to the seventh embodiment.

[0021] Figure 13 It is a top view of a carriage showing the head arrangement according to the eighth embodiment.

[0022] Figure 14A It is a top view of a carriage showing the head arrangement according to the ninth embodiment.

[0023] Figure 14B It is a top view of a carriage showing the head arrangement according to the ninth embodiment.

[0024] Figure 14C It is a top view showing a comparative example for Example 9.

[0025] Figure 15A This is a top view of a carriage showing the head arrangement according to the tenth embodiment.

[0026] Figure 15B This is a top view of a carriage showing the head arrangement according to the tenth embodiment.

[0027] Figure 15C This is a top view of a carriage showing the head arrangement according to the tenth embodiment.

[0028] Figure 15D It is a top view showing a comparative example for Example 10.

[0029] Figure 16 It is a top view of a carriage showing the head arrangement and sub-tank arrangement according to Example 11. DETAILED DESCRIPTION

[0030] An embodiment of the present invention is described below with reference to the accompanying drawings. In this embodiment, an inkjet printer equipped with an ink head that ejects ink for image formation onto a wide and long recording medium is illustrated as a specific example of an inkjet recording device. The inkjet printer of this embodiment is suitable for digital printing, where images such as text and patterns are printed onto recording media made of materials such as woven and knitted fabrics using an inkjet method. Of course, the inkjet recording device of the present invention can also be used to print various inkjet images onto recording media such as paper and resin sheets.

[0031] [Overall structure of an inkjet printer]

[0032] Figure 1 1 is a perspective view showing the overall structure of an inkjet printer 1 according to an embodiment of the present invention. Figure 2 yes Figure 1 The inkjet printer 1 is a schematic cross-sectional view taken along line II-II. The inkjet printer 1 is a printer that prints images on a wide and long workpiece W (recording medium) using an inkjet method. The printer includes a device frame 10, a workpiece conveyor 20 (conveying unit) assembled to the device frame 10, and a carriage 3. In this embodiment, the left-right direction is the main scanning direction when printing on the workpiece W, and the direction from back to front is the secondary scanning direction (the conveying direction F of the workpiece W).

[0033] The device frame 10 forms the framework for mounting the various components of the inkjet printer 1. The workpiece transport unit 20 is a mechanism for intermittently transporting the workpiece W so that it advances along a transport direction F from back to front within the printing area where the inkjet printing process is performed. The carriage 3 carries the ink head 4, pre-processing head 5, post-processing head 6, and auxiliary tank 7, and reciprocates in the left-right direction during the inkjet printing process.

[0034] The device frame 10 includes a central frame 111, a right frame 112, and a left frame 113. The central frame 111 forms the framework for mounting the various components of the inkjet printer 1 and has a width corresponding to the width of the workpiece conveyor 20. The right frame 112 and the left frame 113 are respectively disposed upright on the right and left sides of the central frame 111. Between the right frame 112 and the left frame 113 is the print area 12 where the workpiece W is printed.

[0035] The right frame 112 forms a maintenance area 13. The maintenance area 13 is where the carriage 3 retreats when printing is not in progress. Cleaning and purging of the ejection ports of the ink head 4, pre-processing head 5, and post-processing head 6 are performed in the maintenance area 13, which is also covered. The left frame 113 forms a turnaround area 14 for the carriage 3. The turnaround area 14 is where the carriage 3, which scans the print area 12 from right to left during printing, temporarily enters before reversing the scan.

[0036] A carriage guide 15 is assembled above the device frame 10 to reciprocate the carriage 3 in the left-right direction. The carriage guide 15 is a flat, horizontally elongated member and is positioned above the workpiece conveyor 20. A timing belt 16 (moving member) is assembled on the carriage guide 15 so that it can rotate in the left-right direction (main scanning direction). The timing belt 16 is an endless belt that is driven by a drive source (not shown) to rotate in the left-right or right-hand direction.

[0037] A pair of upper and lower guide rails 17 are provided on the carriage guide 15, extending parallel to each other in the left-right direction. These guide rails serve as holding members for the carriage 3. The carriage 3 engages with the guide rails 17. Furthermore, the carriage 3 is secured to a timing belt 16. As the timing belt 16 rotates in the left or right direction, the carriage 3 is guided by the guide rails 17 and moves left or right along the carriage guide 15.

[0038] Main reference Figure 2 The workpiece conveying unit 20 includes a feed roller 21 for delivering the pre-printed workpiece W and a take-up roller 22 for taking up the printed workpiece W. The feed roller 21 is located at the lower rear portion of the device frame 10 and serves as the winding axis for the feed roll WA, which is the winding body for the pre-printed workpiece W. The take-up roller 22 is located at the lower front portion of the device frame 10 and serves as the winding axis for the take-up roll WB, which is the winding body for the printed workpiece W. The take-up roller 22 is attached to the first motor M1, which drives the take-up roller 22 to rotate about its axis and take up the workpiece W.

[0039] The path between the delivery roller 21 and the take-up roller 22 and through the print area 12 serves as the conveyance path for the workpiece W. This conveyance path is arranged, in order from the upstream side, with a first tension roller 23, a workpiece guide 24, a conveyance roller 25, a pinch roller 26, a return roller 27, and a second tension roller 28. The first tension roller 23 applies a predetermined tension to the workpiece W upstream of the conveyance roller 25. The workpiece guide 24 changes the conveyance direction of the workpiece W from upward to forward, allowing the workpiece W to enter the print area 12.

[0040] The transport roller 25 generates a conveying force that intermittently transports the workpiece W through the print area 12. Driven by the second motor M2, the transport roller 25 rotates about its axis, intermittently transporting the workpiece W forward (in the predetermined conveying direction F) so that the workpiece W passes through the print area 12 (image forming position) facing the carriage 3. The pinch roller 26 is positioned above the transport roller 25, forming a transport nip with the transport roller 25.

[0041] The folding roller 27 changes the conveyance direction of the workpiece W passing through the print area 12 from the forward direction to the downward direction, and guides the printed workpiece W to the take-up roller 22. The second tension roller 28 applies a predetermined tension to the workpiece W downstream of the conveying roller 25. In the print area 12, a platen 29 is arranged below the conveyance path of the workpiece W.

[0042] The carriage 3 reciprocates in a main scanning direction (in this embodiment, the left-right direction) that intersects (in this embodiment, is perpendicular to) the conveying direction F while being cantilevered by the guide rails 17. The carriage 3 includes a carriage frame 30, an ink head 4, a pre-processing head 5, a post-processing head 6, and a sub-tank 7 mounted on the carriage frame 30. The carriage frame 30 includes a head support frame 31 and a rear frame 32 (engaging portion).

[0043] The head support frame 31 is a horizontal plate that holds the heads 4 to 6 described above. The rear frame 32 is a vertical plate that extends upward from the rear end edge of the head support frame 31. As described above, the timing belt 16 is fixed to the rear frame 32. In addition, the guide rail 17 is engaged with the rear frame 32. That is, in this embodiment, the rear frame 32 is an engaging portion that is held by the guide rail 17 in a cantilevered state. The head support frame 31 is a horizontal plate whose rear end side is supported by the engaging portion in a cantilevered state.

[0044] Furthermore, the cantilevered state indicates a state in which the engaging portion (rear frame 32) of the carriage 3 exists only on one side, either upstream or downstream, from the center of the carriage 3 in the conveying direction F, and no other engaging portion exists on the opposite side of the engaging portion. The engaging portion is retained by the guide rail 17, which serves as a retaining member. The engaging portion may also be positioned outside the range where the ink head 4 and the processing head are positioned in the conveying direction F. In other words, the engaging portion may be positioned upstream or downstream of the range where the ink head 4 and the processing head are positioned in the conveying direction F.

[0045] [Detailed structure of the carriage]

[0046] The carriage 3 will be further described. Figure 3 yes Figure 1 An enlarged perspective view of the carriage 3 is shown. Figure 3 , a conveyance direction F (sub-scanning direction) of the workpiece W and a main scanning direction S which is a moving direction of the carriage 3 are shown. Figure 3 The figure shows an example in which a plurality of ink heads 4 for ejecting ink for image formation onto a workpiece W, a pre-processing head 5 and a post-processing head 6 for ejecting a non-coloring processing liquid, and a plurality of auxiliary tanks 7 for supplying the ink and the processing liquid to these heads 4 to 6 are mounted on a slide 3.

[0047] Each ink head 4 includes: a plurality of nozzles (ink ejection holes) that eject ink droplets in an ejection manner, such as a piezoelectric manner using a piezoelectric element, a thermal manner using a heating element, and an ink channel that guides the ink to the nozzle. As the ink, for example, an aqueous pigment ink containing an aqueous solvent, a pigment, and a binder resin can be used. The plurality of ink heads 4 in this embodiment include first to sixth ink heads 4A to 4F that eject inks of six different colors from each other. For example, the first ink head 4A ejects orange (first color) ink, the second ink head 4B ejects green (second color) ink, the third ink head 4C ejects yellow ink, the fourth ink head 4D ejects red ink, the fifth ink head 4E ejects blue ink, and the sixth ink head 4F ejects black ink.

[0048] The ink heads 4A to 4F of each color are mounted on the head support frame 31 of the carriage 3 in such a manner as to be arranged in the main scanning direction S. Each of the ink heads 4A to 4F of each color has two heads. For example, the first ink head 4A includes: an upstream head 4A1 configured on the upstream side of the conveying direction F; and a downstream head 4A2 configured at a position that is located on the downstream side relative to the upstream head 4A1 and offset to the left side of the main scanning direction S. The ink heads 4B to 4F of other colors are also the same. Each upstream head of these ink heads 4B to 4F is aligned in a row along the main scanning direction S at the same position as the upstream head 4A1 in the conveying direction F, and each downstream head is aligned in a row along the main scanning direction S at the same position as the downstream head 4A2 in the conveying direction F.

[0049] The pre-processing head 5 and the post-processing head 6 are arranged at positions different from the ink head 4 in the conveying direction F. The pre-processing head 5 is arranged on the upstream side of the ink head 4 in the conveying direction F. Figure 3 , an example is shown in which one pre-processing head 5 is arranged near the right end of the array of ink heads 4. In contrast, the post-processing head 6 is arranged on the downstream side of the conveying direction F of the ink heads 4. Figure 3 1 shows an example in which two post-processing heads 6A and 6B (a plurality of processing heads) are arranged in the main scanning direction S near the right end of the arrangement body of the ink head 4. Various arrangements of the ink head 4, pre-processing head 5, and post-processing head 6 on the carriage 3 will be described in detail in Examples 1 to 11 described below.

[0050] As used in the above description, a series of heads formed by the ink heads 4 and the post-processing heads 6 along the main scanning direction S is referred to as a head column or simply a column. A head column may also include the pre-processing head 5. Furthermore, a series of heads formed by the ink heads 4, the pre-processing heads 5, and the post-processing heads 6 along the transport direction F is referred to as a head row or simply a column.

[0051] The pretreatment head 5 ejects a pretreatment liquid for performing a predetermined pretreatment on the workpiece W. The pretreatment liquid is ejected from the pretreatment head 5 toward a portion of the workpiece W where ink has not yet been ejected from the ink head 4. The pretreatment liquid is a non-colored treatment liquid that does not exhibit color even when adhered to the workpiece W. For example, the pretreatment liquid functions to improve the fixability of the ink to the workpiece W and the aggregation of the ink pigment. Examples of such pretreatment liquids include those containing a binder resin mixed in a solvent or those containing a positively charged cationic resin mixed in a solvent.

[0052] The post-processing head 6 ejects a post-processing liquid for performing a predetermined post-processing onto the workpiece W to which the ink has adhered. The post-processing liquid is ejected from the post-processing head 6 toward the position on the workpiece W after the ink has been ejected from the ink head 4. The post-processing liquid is also a non-colored processing liquid that does not exhibit color even when adhered to the workpiece W. It functions to improve the fixability and durability (resistance to friction and scratches) of the ink image printed on the workpiece W by the ink head 4. Silicone-based processing liquids, for example, can be used as such a post-processing liquid.

[0053] Here, a non-colored treatment liquid refers to a treatment liquid whose coloration cannot be discerned by the naked eye when printed on a recording medium alone. The colors here include colors with a chroma of 0, such as black, white, and gray. A non-colored treatment liquid is basically a transparent liquid, but when 1L of the treatment liquid is observed in its liquid state, it is not completely transparent and sometimes appears slightly white. This color is very light, and when printed on a recording medium alone, the coloration cannot be discerned by the naked eye. In addition, depending on the type of treatment liquid, when printed on a recording medium alone, the recording medium may sometimes undergo changes such as gloss, but this state does not constitute coloration.

[0054] In this embodiment, the pre-treatment liquid and the post-treatment liquid may be sprayed onto substantially the entire surface of the workpiece W, or may be selectively sprayed like ink according to the image to be printed.

[0055] Next, we will explain the selective ejection of pre-treatment liquid and post-treatment liquid. As described above, for portions of the workpiece W corresponding to the image's printed colors, pre-treatment liquid, ink, and post-treatment liquid are ejected in that order. In this case, the ink can be a single color or multiple colors. For portions not printed, i.e., portions not ejected with ink, pre-treatment liquid and post-treatment liquid are generally not ejected. Furthermore, to adjust the quality of the printed image, the texture of the workpiece W, and so on, the ejection of a portion of the pre-treatment liquid and post-treatment liquid can be selectively performed differently from the ejection of the ink.

[0056] The head support frame 31 has openings 31H at the head placement location. The ink heads 4A to 4F, the pre-processing head 5, and the post-processing head 6 are assembled to the head support frame 31 so as to fit into the respective openings 31H. The nozzles arranged on the lower end surfaces of the heads 4, 5, and 6 are exposed through the respective openings 31H.

[0057] The sub-tanks 7 are supported by the carriage 3 above the heads 4, 5, and 6 via a holding frame (not shown). The sub-tanks 7 are provided corresponding to the heads 4, 5, and 6, respectively. Ink or processing liquid is supplied to each sub-tank 7 from an ink cartridge or main tank (not shown) containing ink and processing liquid. Each sub-tank 7 supplies the ink or processing liquid to each head 4, 5, and 6. Each sub-tank 7 and the heads 4, 5, and 6 are connected to each other. Figure 3 Through the pipeline (not shown) Figure 16 P1, P2, P3) shown in are connected.

[0058] As described above, the inkjet printer 1 of this embodiment is a multifunction all-in-one printer equipped with three heads: an ink head 4, a pre-processing head 5, and a post-processing head 6, mounted on a single carriage 3. This printer 1 can, for example, perform both the pre-processing liquid and post-processing liquid ejection steps during the printing process of inkjet printing on a material in digital printing. This simplifies the printing process and reduces the size of the printing apparatus.

[0059] [Print Method]

[0060] Next, a description will be given of a printing method performed by the inkjet printer 1 according to this embodiment. The inkjet printer 1 performs a printing process on the workpiece W using a serial printing method. Figure 4 : is a schematic diagram showing the serial printing method. Figure 4 In FIG, the pre-processing head 5 and the post-processing head 6 are omitted and the carriage 3 is simply drawn.

[0061] If the workpiece W is wide, printing cannot be performed while continuously feeding the workpiece W. The serial printing method is a printing method that repeats the reciprocating movement of the carriage 3 carrying the ink heads 4 of each color in the main scanning direction S and the intermittent feeding of the workpiece W in the feeding direction F. Here, it is assumed that the ink head 4 has a predetermined printing width Pw in the feeding direction F. The printing width Pw is approximately equal to the range of the ink ejection nozzles of the ink head 4.

[0062] In addition, Figure 4 5 described below, the width of each head in the conveying direction F is drawn as being substantially equal to the printing width Pw. In reality, the width of each head in the conveying direction F is larger than the printing width Pw and the arrangement range of the ejection nozzles.

[0063] Figure 4 The figure shows the state where the carriage 3 moves in the outward direction SA of the main scanning direction S and the printing of the strip image G1 with the printing width Pw is completed. When scanning in the outward direction SA, the conveyance of the workpiece W stops. After printing the strip image G1, the workpiece W is sent in the conveying direction F by a spacing equivalent to the printing width Pw. At this time, the carriage 3 waits in the folding area 14 on the left end side. After sending out the workpiece W, the carriage 3 folds back in the return direction SB as the synchronous belt 16 rotates in the reverse direction. The workpiece W is in a stopped state. Then, as shown Figure 4 As shown, the carriage 3 moves in the return path direction SB and prints a band-like image G2 having a print width Pw on the upstream side of the band-like image G1. Thereafter, the same operation is repeated.

[0064] Figure 5A and Figure 5BSchematic diagrams showing the printing conditions of the carriage 3 on the forward and return paths. A simplified illustration of the ink head 4, pre-processing head 5, and post-processing head 6 mounted on the carriage 3 is shown. The ink head 4 includes first, second, third, and fourth ink heads 4A, 4B, 4C, and 4D for ejecting inks of different first, second, third, and fourth colors. These first to fourth ink heads 4A to 4D are arranged in a row along the main scanning direction S. The pre-processing head 5 is arranged upstream of the ink head 4 in the conveying direction F, and the post-processing head 6 is arranged downstream.

[0065] Figure 5A 3 shows a state in which the carriage 3 is performing a printing operation (forward scanning) while moving in the forward direction SA of the main scanning direction S. Area A4 on the workpiece W is the area facing the pre-processing head 5 mounted on the most upstream side of the carriage 3. During this forward scanning, the pre-processing liquid ejected from the pre-processing head 5 forms a pre-processing layer Lpre on area A4.

[0066] Area A3 is an area that is one scan distance downstream of area A4 and is the area where the ink head 4 is directed. In area A3, a pre-processing layer Lpre has been formed along the entire length in the main scanning direction by the previous return scan. In this forward scan, the first to fourth color inks ejected in the order of arrangement of the first to fourth ink heads 4A to 4D on the pre-processing layer Lpre of area A3 form the first, second, third, and fourth ink layers LCA, LCB, LCC, and LCD. In addition, for ease of understanding, Figure 5A In the figure, the fourth to first ink layers LCD to LCA are sequentially stacked, but they are not actually stacked. In addition, the aforementioned pre-processing layer Lpre and the post-processing layer Lpos described later are not formed on the workpiece W.

[0067] Area A2 is the area one scan distance downstream of area A3 and is the area faced by the post-processing head 6, mounted on the most downstream side of the carriage 3. Area A2 has already been formed along its entire length in the main scanning direction with the pre-processing layer Lpre formed by the previous forward scan and the first to fourth ink layers LCA to LCD formed by the previous return scan. During this forward scan, the post-processing liquid ejected from the post-processing head 6 forms a post-processing layer Lpos on the first to fourth ink layers LCA to LCD in area A2.

[0068] Area A1 is a region downstream of area A2 by a distance of one scan, and is the region where the printing process ends after the carriage 3 passes through. Specifically, in area A1, the pre-processing layer Lpre, the first to fourth ink layers LCA to LCD, and the post-processing layer Lpos are formed over the entire length in the main scanning direction.

[0069] Figure 5B Indicates the end Figure 5A After the outward scan, the carriage 3 turns back and continues its return scan while moving in the return direction SB. Prior to this return scan, the workpiece W is fed a distance of one pitch in the conveyance direction F. Area A5 on the workpiece W is located upstream of area A4 by one scan distance and is the area that the pretreatment head 5 faces during this return scan. A pretreatment layer Lpre is formed on area A5 by the pretreatment liquid ejected from the pretreatment head 5.

[0070] In areas A4 and A3, the first to fourth ink layers LCA to LCD and the post-processing layer Lpos are formed on the existing layers, respectively. Specifically, in area A4, the first to fourth ink layers LCA to LCD are formed on the pre-processing layer Lpre. In area A3, the post-processing layer Lpos is formed on the first to fourth ink layers LCA to LCD. Area A2 is the area where the printing process ends after area A1.

[0071] The reason why printing can be performed on both the forward scanning and the return scanning as described above is that the pre-processing head 5 and the post-processing head 6 are arranged in an offset manner relative to the ink head 4 in the conveying direction F. Assuming that the pre-processing head 5, the ink head 4, and the post-processing head 6 are arranged in a row in this order along the main scanning direction S on the carriage 3, it is possible to ensure that the printing process of the desired landing order of the pre-processing liquid and the post-processing liquid can be achieved only on the forward scanning or return scanning side. In order to be able to perform printing in both directions, a pair of pre-processing heads 5 and post-processing heads 6 must be arranged on both sides of the arrangement body of the ink head 4. At this time, the width of the carriage 3 in the main scanning direction S becomes larger. Since such a configuration is not required in the present embodiment, the width of the carriage 3 in the main scanning direction S can be miniaturized.

[0072] [Various ways to configure the header]

[0073] Various configuration examples of the ink head 4, pre-processing head 5, and post-processing head 6 on the carriage 3 are described below as Examples 1 to 11. Furthermore, Examples 1 to 11 illustrate examples in which both the pre-processing head 5 and the post-processing head 6 are included as processing heads. However, if at least one of the pre-processing head 5 and the post-processing head 6 is provided in plurality and arranged in the main scanning direction at a position different from the ink head 4 in the transport direction F, either the pre-processing head 5 or the post-processing head 6 may be omitted.

[0074] <Example 1>

[0075] Figure 6 This is a plan view schematically showing the head configuration according to the first embodiment. Figure 6It also means Figure 3 The figure shows the arrangement of the ink heads 4, pre-processing heads 5, and post-processing heads 6 (multiple processing heads) on the carriage 3. As mentioned above, the head support frame 31 of the carriage 3 carries the first to sixth ink heads 4A to 4F, which eject six different colors of ink, the pre-processing heads 5, and the post-processing heads 6. Each of the ink heads 4A to 4F has two unit heads (a total of 12). There is one pre-processing head 5, and two post-processing heads 6.

[0076] The group of first to sixth ink heads 4A to 4F constituting the ink head 4 is arranged so as to be aligned along the main scanning direction S in the central region of the head support frame 31 in the conveying direction F. The pre-processing head 5 is arranged upstream of the ink head 4 in the conveying direction F and on the base end 311 of the head support frame 31. On the other hand, the post-processing head 6 is arranged downstream of the ink head 4 in the conveying direction F and on the distal end 312 of the head support frame 31. Both the pre-processing head 5 and the post-processing head 6 are arranged near one end (the right end) of the head support frame 31 in the main scanning direction S.

[0077] The first ink head 4A includes an upstream head 4A1 and a downstream head 4A2 positioned downstream of the upstream head 4A1. Specifically, the upstream head 4A1 and the downstream head 4A2 are aligned in the conveying direction F. The upstream head 4A1 is positioned near the base end 311 in the central region of the head support frame 31. The downstream head 4A2 is positioned near the distal end 312 in the central region of the head support frame 31. The downstream head 4A2 is positioned offset to one side (left side) in the main scanning direction S relative to the upstream head 4A1, with a portion of the head 4A2 overlapping in the conveying direction F. Of course, the upstream head 4A1 and the downstream head 4A2 can also be arranged at the same position in the main scanning direction S (aligned in a straight line in the conveying direction F). However, the configuration of this embodiment is more advantageous in that it enables the carriage 3 to be miniaturized in the conveying direction F.

[0078] The second to sixth ink heads 4B to 4F also include upstream heads 4B1, 4C1, 4D1, 4E1, and 4F1, and downstream heads 4B2, 4C2, 4D2, 4E2, and 4F2, similar to the upstream head 4A1 and downstream head 4A2 described above. The upstream heads 4A1 to 4F1 of the first to sixth ink heads 4A to 4F are arranged in a row at predetermined intervals along the main scanning direction S at the same position in the conveying direction F. Furthermore, the downstream heads 4A2 to 4F2 are also arranged in a row at predetermined intervals along the main scanning direction S at the same position in the conveying direction F. As a result, a zigzag arrangement is formed, with portions of the downstream heads 4A2 to 4F2 intersecting the respective arrangement intervals of the upstream heads 4A1 to 4F1.

[0079] The preprocessing head 5 is arranged so that a portion thereof enters between a pair of ink heads adjacent to each other in the main scanning direction S. Specifically, the downstream portion of the preprocessing head 5 enters between the upstream head 4E1 of the fifth ink head 4E and the upstream head 4F1 of the sixth ink head 4F.

[0080] The post-processing head 6 includes a first post-processing head 6A and a second post-processing head 6B arranged in parallel in the main scanning direction S. Figure 6 ] shows an example in which the first and second post-processing heads 6A and 6B are arranged at the same position in the conveying direction F, spaced apart along the main scanning direction S at predetermined intervals. The first post-processing head 6A is positioned so that its upstream portion extends between the downstream head 4E2 of the fifth ink head 4E and the downstream head 4F2 of the sixth ink head 4F. The second post-processing head 6B is positioned to the right of the downstream head 4F2 and at the same position in the main scanning direction S as the upstream head 4F1. With this arrangement, the first and second post-processing heads 6A and 6B overlap with the downstream heads 4E2 and 4F2 in the conveying direction F in an area fa.

[0081] In the transport direction F, the width of each head is larger than the printing width Pw and the arrangement range of the ejection nozzles. Therefore, the heads are arranged to have an overlapping area fa so that there is no gap between the printing width Pw of each row of heads and the printing range Pw of the adjacent row of heads.

[0082] As a result of the above-described head arrangement, the pre-processing head 5 and the post-processing head 6 are arranged within the arrangement width H of the ink head 4 in the main scanning direction S. The ink head 4 has an arrangement width H between the downstream head 4A2 of the first ink head 4A and the upstream head 4F1 of the sixth ink head 4F in the main scanning direction S. The pre-processing head 5 is arranged within the arrangement width H on the upstream side of the ink head 4, and the post-processing head 6 is arranged within the arrangement width H on the downstream side of the ink head 4.

[0083] According to the head configuration involved in the embodiment 1 described above, it is possible to achieve the miniaturization of the carriage 3 and ensure the necessary amount of ink and treatment liquid ejected. That is, the pre-processing head 5 and the post-processing head 6 are arranged at a different position from the ink head 4 in the conveying direction F. According to this configuration, the ink heads 4A to 4F that can ensure the necessary amount of ink ejected are arranged in the main scanning direction S, and can perform printing processing in both the forward scanning and return scanning directions, and the width of the carriage required for carrying the above-mentioned heads 4 to 6 in the main scanning direction can be shortened. Moreover, the post-processing head 6 is composed of a plurality of first and second post-processing heads 6A and 6B, and they are arranged in the main scanning direction S. Therefore, if the amount of post-processing liquid ejected is insufficient if a single head is used, the necessary amount of ejection can also be ensured by configuring a plurality of post-processing heads 6A and 6B.

[0084] The first to sixth ink heads 4A to 4F include upstream heads 4A1 to 4F1 and downstream heads 4A2 to 4F2, respectively, arranged along the transport direction F (a direction intersecting the arrangement direction of the multiple processing heads). Therefore, even if the number of ink heads 4 is increased to increase the amount of ink ejected per color or to achieve multi-color printing, the width of the carriage 3 in the main scanning direction can be prevented from being increased.

[0085] The pre-processing head 5 and the post-processing head 6 are arranged within the arrangement width H of the first to sixth ink heads 4A to 4F in the main scanning direction S. Therefore, even when the carriage 3 carries the pre-processing head 5 and the post-processing head 6 in addition to the ink heads 4, there is no need to increase the width of the carriage 3 in the main scanning direction. In other words, the width of the carriage 3 in the main scanning direction can be made less likely to be enlarged.

[0086] The pre-processing heads 5 and post-processing heads 6 are arranged so that portions of them extend between the arrangement intervals of the first to sixth ink heads 4A to 4F. Focusing on the first post-processing head 6A, a portion of the first post-processing head 6A extends between the pair of downstream heads 4E2 and 4F2. This zigzag arrangement allows for high-density arrangement of the ink heads 4 and the processing heads 5 and 6 at different positions in the conveying direction F. Consequently, the width of the carriage 3 in the conveying direction F can be reduced.

[0087] In the head arrangement of Example 1, a pre-processing head 5 is positioned upstream of the ink head 4 in the transport direction F, and two post-processing heads 6A and 6B are positioned downstream. This provides a multifunctional, all-in-one inkjet printer 1 in which the heads for discharging the pre-processing liquid, ink, and post-processing liquid are all mounted on a single carriage 3. Furthermore, because the pre-processing head 5, ink head 4, and post-processing head 6 are sequentially positioned in the transport direction F, the desired order of landing of the pre-processing liquid, ink, and post-processing liquid on the workpiece W can be ensured during both forward and return scanning.

[0088] The carriage 3 also includes a rear frame 32 (engaging portion) held in a cantilevered position by the guide rail 17 (holding member). By supporting the carriage 3 in a cantilevered position on the timing belt 16, the structure can be simplified. Furthermore, by supporting the carriage 3 in a cantilevered position, it is easy to open the downstream side of the carriage 3, making maintenance of the ink head 4 and the processing heads 5 and 6 easier.

[0089] In the carriage 3 supported in a cantilevered state, the pre-processing head 5 is arranged on the base end side 311 (the side close to the joint) of the head support frame 31, and the post-processing head 6 is arranged on the distal end side 312 (the side away from the engaging portion). Unlike the base end side 311 close to the rear frame 32 fixed to the timing belt 16, the estimated position accuracy is inevitably reduced on the distal end side 312, which serves as the free end. However, the post-processing head 6, which does not require relatively strict high ejection accuracy, is mounted on the distal end side 312. Since the post-processing liquid covers the ink image printed on the workpiece W, even if the landing position shifts, the relative impact on the image quality can be reduced compared to the same degree of landing position shift of the pre-processing liquid. Therefore, even when using the carriage 3 supported in a cantilevered state, it is possible to prevent the image quality from being degraded.

[0090] <Example 2>

[0091] Figure 7 1 is a top view schematically showing a carriage 3A having a head configuration according to Example 2. The head configuration method is the same as that of Example 1, and the difference from Example 1 is that the number of unit heads is increased. That is, in Example 2, each ink head 4 includes the first to sixth ink heads 4A to 4F that eject six different colors of ink, which is the same as in Example 1. On the other hand, the ink heads 4A to 4F of each color in Example 2 each have 3 (a total of 18) unit heads. The pre-processing head 5 arranged on the upstream side in the conveying direction F of the ink head 4 includes 2 unit heads, and the post-processing head 6 arranged on the downstream side includes 3 unit heads. The points at which the pre-processing head 5 and the post-processing head 6 are respectively arranged within the range of the configuration width of the ink head 4 in the main scanning direction S are also the same as in Example 1.

[0092] The first ink head 4A includes an upstream head 4AA, a central head 4AB, and a downstream head 4AC as the unit heads. The upstream head 4AA is positioned at the most upstream side of the carriage 3A in the conveying direction F. The downstream head 4AC is positioned downstream of the upstream head 4AA at the same position as the upstream head 4AA in the main scanning direction S. The central head 4AB is positioned to the right of the upstream head 4AA and the downstream head 4AC in the main scanning direction S, and is positioned downstream of the upstream head 4AA and upstream of the downstream head 4AC in the conveying direction F. The central head 4AB is positioned so as to partially overlap with each of the upstream head 4AA and the downstream head 4AC in the conveying direction F.

[0093] The second to sixth ink heads 4B to 4F also include upstream heads 4BA, 4CA, 4DA, 4EA, 4FA, center heads 4BB, 4CB, 4DB, 4EB, 4FB, and downstream heads 4BC, 4CC, 4DC, 4EC, and 4FC, similar to the upstream head 4AA, center head 4AB, and downstream head 4AC described above. The upstream heads 4AA to 4FA, center heads 4BB to 4FB, and downstream heads 4BC to 4FC of the first to sixth ink heads 4A to 4F are arranged in a row along the main scanning direction S at predetermined intervals at the same position in the transport direction F.

[0094] The pre-processing heads 5 include a first pre-processing head 5A and a second pre-processing head 5B, arranged at intervals along the main scanning direction S at the same position in the conveying direction F. The first pre-processing head 5A is arranged so that a portion of its downstream side extends between the upstream head 4EA of the fifth ink head 4E and the upstream head 4FA of the sixth ink head 4F. The second pre-processing head 5B is arranged to the right of the upstream head 4FA and at the same position in the main scanning direction S as the center head 4FB.

[0095] The post-processing heads 6 include a first post-processing head 6A, a second post-processing head 6B, and a third post-processing head 6C, arranged at intervals along the main scanning direction S at the same position in the conveying direction F. The first post-processing head 6A is arranged so that a portion of its upstream side extends between the downstream head 4DC of the fourth ink head 4D and the downstream head 4EC of the fifth ink head 4E. The second post-processing head 6B is arranged so that a portion of its upstream side extends between the downstream head 4EC of the fifth ink head 4E and the downstream head 4FC of the sixth ink head 4F. The third post-processing head 6C is arranged to the right of the downstream head 4FC and at the same position in the main scanning direction S as the center head 4FB.

[0096] The head configuration of Example 2 achieves the same advantages as Example 1. Specifically, it achieves miniaturization of the carriage 3 while ensuring the necessary ink and treatment fluid ejection rates. In particular, in Example 2, both the pre-processing head 5 and the post-processing head 6 are configured with multiple unit heads, ensuring sufficient ejection rates for the pre-processing and post-processing fluids. Since the first to sixth ink heads 4A to 4F also comprise unit heads arranged in three rows, sufficient ink ejection rates are also ensured.

[0097] <Example 3>

[0098] Figure 8 This is a plan view schematically showing a carriage 3B having a head arrangement according to Example 3. Example 3 shows an example in which an ink head 4 that ejects ink and a pre-processing head 5 and a post-processing head 6 that eject a non-colored processing liquid are arranged separately in the main scanning direction.

[0099] The head support frame 31 of the carriage 3B carries the first to sixth ink heads 4A to 4F, each ejecting six different colors of ink, a pre-processing head 5, and a post-processing head 6. The first to sixth ink heads 4A to 4F comprise unit heads arranged in three rows, similar to those in Example 2. The pre-processing head 5 includes first and second pre-processing heads 5A and 5B, arranged at intervals along the main scanning direction S at the same position in the conveying direction F. The post-processing head 6 includes first to third post-processing heads 6A to 6C, arranged at intervals along the main scanning direction S at the same position in the conveying direction F. Their basic structure is the same as that in Example 2.

[0100] In embodiment 3, the configuration area of ​​the ink head 4 and the configuration area of ​​the pre-processing head 5 and the post-processing head 6 are divided on the head support frame 31. A first area R1 with a larger area and a second area R2 with a smaller area adjacent to the first area R1 in the main scanning direction S are set on the head support frame 31. The ink heads 4 (the first to sixth ink heads 4A to 4F) are configured in the first area R1. On the other hand, the pre-processing head 5 and the post-processing head 6 are not configured in the first area R1, but are configured in the second area R2. In the second area R2, the pre-processing head 5 is configured on the upstream side of the conveying direction F of the array of the ink heads 4, and the post-processing head 6 is configured on the downstream side.

[0101] If ink comes into contact with the pre-treatment liquid or post-treatment liquid, ink components may aggregate. If this aggregate adheres to the ink ejection nozzles of the ink head 4, poor ejection may occur. Furthermore, there is a risk that the ink may come into contact with the treatment liquid and aggregate in the recovery system for waste liquid generated during head cleaning and purging, potentially clogging the recovery path. The carriage 3B of Example 3, with the treatment heads 5 and 6 and ink head 4 separated in the main scanning direction, minimizes contact between the ink and the pre-treatment liquid or post-treatment liquid. Consequently, problems caused by ink aggregation are minimized.

[0102] <Example 4>

[0103] Figure 9 This is a top view schematically showing a carriage 3C equipped with a head arrangement according to Example 4. In Examples 1 to 3 above, the pre-processing head 5 and the post-processing head 6 were arranged near the end (near the right end) of the arrangement width H of the ink head 4 in the main scanning direction S. In Example 4, the pre-processing head 5 and the post-processing head 6 were arranged in the center region HC of the arrangement width H.

[0104] Mounted on the head support frame 31 of the carriage 3C are the first to sixth inkjet heads 4A to 4F, each ejecting six different colors of ink, a pre-processing head 5, and a post-processing head 6. The first to sixth inkjet heads 4A to 4F are comprised of unit heads arranged in two rows, similar to those in Example 1. However, in the first inkjet head 4A, the downstream head 4A2 is positioned to the right of the upstream head 4A1, and the offset direction of the downstream heads of each inkjet head 4A to 4F is opposite to that in Example 1. There is one pre-processing head 5, and two post-processing heads 6, namely, a first and a second post-processing head 6A and 6B.

[0105] The pre-processing head 5 and the post-processing head 6 are arranged in the center area HC of the arrangement width H of the first to sixth ink heads 4A to 4F in the main scanning direction S. The arrangement of the pre-processing head 5 upstream in the conveyance direction F of the array of the first to sixth ink heads 4A to 4F and the post-processing head 6 downstream is similar to that of the above-described Embodiments 1 to 3. The pre-processing head 5 is arranged at the same position in the main scanning direction S as the downstream head 4C2 of the third ink head 4C and upstream in the conveyance direction F. The pre-processing head 5 is arranged so that a portion of its downstream side extends between the upstream heads 4C1 and 4D1 of the third and fourth ink heads 4C and 4D.

[0106] The first and second post-processing heads 6A and 6B are arranged at the same position in the transport direction F, spaced apart in the main scanning direction S. The first post-processing head 6A is positioned so that its upstream portion extends between the downstream head 4B2 of the second ink head 4B and the downstream head 4C2 of the third ink head 4C. The second post-processing head 6B is positioned so that its upstream portion extends between the downstream head 4C2 and the downstream head 4D2 of the fourth ink head 4D.

[0107] The pre-processing head 5 and the post-processing head 6 are not only arranged in the central area HC of the arrangement width H, but are also arranged so that the arrangement center of the pre-processing head 5 and the arrangement centers of the first and second post-processing heads 6A and 6B coincide with each other in the main scanning direction S. In this embodiment, since there is only one pre-processing head 5, the center of the pre-processing head 5 in the main scanning direction S becomes the arrangement center C1. With respect to the post-processing heads 6, the midpoint between the first post-processing head 6A and the second post-processing head 6B becomes the arrangement center C2. The pre-processing heads 5 and the post-processing heads 6 are arranged on the head support frame 31 so that their arrangement centers C1 and arrangement centers C2 are located at the same position in the main scanning direction S.

[0108] If based on Figure 4As described, in this embodiment, the carriage 3 repeatedly performs forward scanning and return scanning, causing the pre-treatment liquid, ink, and post-treatment liquid to sequentially land on the workpiece W. By employing the head arrangement of Example 4 while employing such bidirectional scanning, it is possible to reduce variations in the time from the landing of the pre-treatment liquid on the workpiece W to the landing of the ink, and in the time from the landing of the ink to the landing of the post-treatment liquid, at each main scanning position.

[0109] In this case, the central region HC is a region located in the center of the range of the arrangement width H and having a width of half or one-third of the arrangement width H. Arranging the processing heads in the central region HC means that the arrangement centers of the processing heads are arranged in the central region HC, and more than half of the arrangement centers of the processing heads are arranged in the central region HC. Alternatively, all arrangement centers of the processing heads may be arranged in the central region HC.

[0110] <Example 5>

[0111] Figure 10 This is a plan view schematically showing a carriage 3D having a head arrangement according to Example 5. Example 5 shows an example in which the pre-processing head 5 and the post-processing head 6 are separately arranged at one end and the other end of the head support frame 31 in the main scanning direction S with the ink head 4 interposed therebetween.

[0112] The head support frame 31 is equipped with the same Figure 9 ) The first to sixth ink heads 4A to 4F, the pre-processing head 5, and the post-processing head 6 are arranged identically. The pre-processing head 5 includes one head, and the post-processing head 6 includes two heads, a first post-processing head 6A and a second post-processing head 6B. The pre-processing head 5 is arranged on one end side (right side) in the main scanning direction S and upstream side in the conveying direction F relative to the ink head 4. The first and second post-processing heads 6A and 6B are arranged on the other end side (left side) in the main scanning direction S and downstream side in the conveying direction F relative to the ink head 4. The first and second post-processing heads 6A and 6B are arranged at the same position in the conveying direction F, spaced apart along the main scanning direction S.

[0113] Similar to Example 3, Example 5 also features a head configuration in which the ink head 4 placement area is divided from the pre-processing head 5 and post-processing head 6 placement areas on the head support frame 31. Specifically, the right end of the head support frame 31 is designated as the placement area for the pre-processing head 5, the left end is designated as the placement area for the post-processing head 6, and the remaining central area is designated as the placement area for the ink head 4. This head configuration of Example 5 also minimizes contact between the ink and the pre-processing liquid or post-processing liquid.

[0114] <Example 6>

[0115] Figure 11This is a top view schematically showing a carriage 3E equipped with a head arrangement according to Example 6. In the above embodiments, an ink head 4 having independent unit heads for each color was exemplified. In Example 6, an ink head 4 having a single head equipped with an ejection portion for ejecting inks of different colors was exemplified.

[0116] The carriage 3E is equipped with two multicolor heads 40A and 40B, a pre-processing head 5, and a post-processing head 6 including first and second post-processing heads 6A and 6B. The multicolor heads 40A and 40B include first, second, third, and fourth ink ejection areas 4a, 4b, 4c, and 4d, which eject four different colors of ink, respectively. The first to fourth ink ejection areas 4a to 4d can be formed by combining unit nozzles that eject ink of each color, or by vertically dividing a plurality of ink ejection nozzles included in a single ink head into the ejection areas for each color.

[0117] The pre-processing head 5 is arranged on the right side of the array of multi-color heads 40A and 40B and upstream in the conveying direction F. The post-processing head 6 is arranged on the downstream side of the array in the conveying direction F. The first and second post-processing heads 6A and 6B are arranged at the same position in the conveying direction F, spaced apart along the main scanning direction S. The first post-processing head 6A is arranged so that its upstream portion extends between the pair of multi-color heads 40A and 40B. This head arrangement according to Example 6 allows for both miniaturization of the carriage 3E and ensuring the required ejection volume of ink and processing liquid.

[0118] <Example 7>

[0119] Figure 12 This is a plan view schematically showing a carriage 3F having a head arrangement according to Example 7. In Example 7, the ink heads 4 are arranged in a row in the main scanning direction S, with first to sixth ink heads 4A to 4F ejecting six different colors of ink, respectively.

[0120] The head support frame 31 of the carriage 3F carries the first to sixth ink heads 4A to 4F, each having two unit heads, a pre-processing head 5, and a post-processing head 6. The pre-processing head 5 comprises one head, and the post-processing head 6 comprises two heads, a first head 6A and a second head 6B. The difference from the above-described embodiments 1 to 5 is that the first to sixth ink heads 4A to 4F, each having two unit heads, are arranged along the main scanning direction S at the same position in the conveyance direction F. The pre-processing head 5 and the post-processing head 6 are respectively arranged upstream and below the right side of the arrangement of the first to sixth ink heads 4A to 4F.

[0121] The head configuration of Example 7 is suitable for situations where the width in the main scanning direction S can be relatively large, but the width in the transport direction F should be reduced. Furthermore, it ensures the necessary ejection volumes of ink and treatment liquid. Furthermore, because the placement area for the ink head 4 is separated from the placement areas for the pre-processing head 5 and the post-processing head 6 by the head support frame 31, contact between the ink and the pre-processing liquid or post-processing liquid is minimized.

[0122] <Example 8>

[0123] In Example 8 and the following Example 9, head configurations are illustrated that take measures to prevent the heating of the processing heads 5 and 6. Typically, a head that ejects liquid using a jetting method generates heat because it uses electricity to pressurize the liquid. The ink head 4 only ejects liquid when forming the desired color dots. In contrast, the pre-processing head 5 and the post-processing head 6 need to eject the pre-processing liquid and the post-processing liquid corresponding to dots of all colors. Therefore, the pre-processing head 5 and the post-processing head 6 are more likely to heat up than the ink heads 4. Therefore, it is preferable to configure the head configuration in such a way that the pre-processing head 5 and the post-processing head 6 will heat up.

[0124] Figure 13 This is a top view schematically showing a carriage 3G having a head configuration according to Example 8. The rear frame 32 (engaging portion) of the carriage 3G is held in a cantilevered state by the guide rail 17 (holding member). The head support frame 31 carries an ink head 4 having first to sixth ink heads 4A to 4F, a pre-processing head 5, and a post-processing head 6 having first and second post-processing heads 6A and 6B. These head configurations are similar to the embodiment 8. Figure 6 The embodiment 1 shown is the same, so the description is omitted here.

[0125] In this embodiment, the pre-processing head 5 is composed of one unit head, and the post-processing head 6 is composed of two unit heads (first and second post-processing heads 6A and 6B). The pre-processing head 5 with fewer unit heads among these pre-processing heads 5 and post-processing heads 6 is arranged on the base end side 311 of the head support frame 31. The post-processing head 6 with more unit heads is arranged on the distal end side 312. In other words, the upstream end edge of the head support frame 31 in the conveying direction F is the side held by the guide rail 17.

[0126] As described above, the processing heads 5 and 6 generate heat due to the ejection operation. Figure 13 As schematically shown in the figure, the heated pre-processing head 5 releases heat ha. The same applies to the first and second post-processing heads 6A and 6B. This heat ha heats the head support frame 31 of the carriage 3G, potentially causing thermal deformation of the head support frame 31, its retaining structure, the rear frame 32, and the mounting brackets between the rear frame 32 and the timing belt 16. This thermal deformation can affect the landing accuracy of ink ejected from the ink head 4 in the cantilevered carriage 3G.

[0127] However, in the carriage 3G of Example 8, the pre-processing head 5, which has a smaller number of unit heads, is positioned on the cantilevered side of the head support frame 31, i.e., the base end side 311. This reduces the effects of thermal deformation (reduced landing accuracy). If the post-processing head 6, which has a larger number of unit heads, is positioned on the base end side 311, the rear frame 32 is exposed to the heat released by the two unit heads, causing it to heat up even more and become more susceptible to thermal deformation.

[0128] Furthermore, in the carriage 3G of Example 8, the pre-processing head 5 is positioned at a location other than the end of the array HA of the ink head 4 and the processing heads 5 and 6 in the main scanning direction S. Of the heads 4, 5, and 6 mounted on the carriage 3G, the pre-processing head 5 is positioned closest to the rear frame 32 (engaging portion). The pre-processing head 5 is positioned at a location other than the end of the head array HA, i.e., the arrangement end 313.

[0129] The carriage 3G cannot be unnecessarily increased in size. Assuming that a head is arranged at the configuration end 313 of the head array body in the main scanning direction S, the head becomes the head closest to the corner of the carriage 3G (head support frame 31) in the main scanning direction S. Since the configuration end 313 is also near the cantilever-supported rear frame 32, if thermal deformation occurs near it, it may cause deformation or positional displacement of the head support frame 31 in the height direction or horizontal direction. This reduces the landing position accuracy of the heads 4, 5, and 6 mounted on the carriage 3G. Therefore, by not arranging the pre-processing head 5 that will heat up in the area of ​​the configuration end 313, the above-mentioned problem of thermal deformation can be made less likely to occur.

[0130] In this embodiment, the row of ink heads 4 arranged on the engaging portion side among the two rows of ink heads 4 is located at the bottom. Figure 13 The zigzag arrangement is arranged in a position offset to the right. Furthermore, the pre-processing head 5, which has a smaller number of processing heads, is arranged on the engaging portion side, and the pre-processing head 5 is arranged at the rightmost position in the zigzag arrangement. This arrangement allows the heads to be arranged without arranging the processing heads at the arrangement end 313.

[0131] Reference Figure 13The head configuration of the carriage 3G shown in the figure illustrates an example of a preferred ink head configuration. In the carriage 3G, the pre-processing head 5, which is subject to high temperature, is configured so that a portion of it is adjacent to the ink head 4. Specifically, the pre-processing head 5 is adjacent to the upstream heads 4E1 and 4F1 of the fifth and sixth ink heads 4E and 4F in the main scanning direction S, and is adjacent to the downstream head 4F2 of the sixth ink head 4F in the conveying direction F. In addition, the first post-processing head 6A is adjacent to the downstream heads 4E2 and 4F2 of the fifth and sixth ink heads 4E and 4F in the main scanning direction S, and is adjacent to the upstream head 4E1 in the conveying direction F. The second post-processing head 6B is adjacent to the upstream head 4F1 and the downstream head 4F2. On the other hand, the pre-processing head 5 and the post-processing head 6 are not adjacent to the first to fourth ink heads 4A to 4D.

[0132] In the above-described head arrangement, for example, the fifth and sixth ink heads 4E and 4F (first ink heads that eject ink of the first color) that eject blue and black ink, respectively, have more unit heads adjacent to the pre-processing head 5 and post-processing head 6 than the first to fourth ink heads 4A to 4D (second ink heads that eject ink of the second color) that eject orange, green, yellow, and red ink, respectively. In other words, the fifth and sixth ink heads 4E and 4F are more susceptible to high temperatures than the other ink heads 4A to 4D.

[0133] If the viscosity of the ink changes significantly with temperature, the ink ejection characteristics (e.g., ejection volume) of the ink head will also change. The viscosity change characteristics due to temperature vary depending on the type of ink. Therefore, in the present embodiment, the ink ejected from the fifth and sixth ink heads 4E and 4F, which are susceptible to high temperatures, is selected to have a viscosity that changes less with temperature than the ink ejected from the first to fourth ink heads 4A to 4D. Consequently, even if the fifth and sixth ink heads 4E and 4F are heated by the pre-processing head 5 and post-processing head 6, changes in the ejection volume and ejection velocity of the ink ejected from these ink heads 4E and 4F due to temperature can be reduced.

[0134] At this time, for each ink, the unit number of processing heads adjacent to the ink head 4 can also be used to evaluate the maximum number of unit numbers of processing heads adjacent to the ink head 4 ejecting a certain ink. For the first to fourth ink heads 4A to 4D, the maximum number of unit numbers of processing heads adjacent to each other is 0. For the fifth ink head 4E, the maximum number of unit numbers of processing heads adjacent to each other is 2. For the sixth ink head 4F, the maximum number of unit numbers of processing heads adjacent to each other is 3.

[0135] Furthermore, for each ink, the unit number of processing heads adjacent to the ink head 4 can also be used to evaluate the average unit number of processing heads adjacent to the ink head 4 ejecting a particular ink. For the first to fourth ink heads 4A to 4D, the average unit number of processing heads adjacent to the ink head 4 is 0. For the fifth ink head 4E, the average unit number of processing heads adjacent to the ink head 4 is 1.5. For the sixth ink head 4F, the average unit number of processing heads adjacent to the ink head 4 is 2.5.

[0136] As a combined evaluation, for example, the maximum number of unit heads of adjacent processing heads can be evaluated first. For inks that do not differ in this evaluation, the average number of unit heads of adjacent processing heads can be evaluated. Alternatively, the order in which the ink heads 4 ejecting each ink are most likely to reach high temperatures can be evaluated, with inks with the smallest temperature variations being ejected in the order in which they are most likely to reach high temperatures being ejected.

[0137] <Example 9>

[0138] Example 9 describes an embodiment that considers countermeasures for high temperatures of the pre-processing head 5 and post-processing head 6 among multiple ink heads that eject the same color ink. In the above embodiments, the first to sixth ink heads 4A to 4F of each color were each equipped with two or three unit heads. If there is a significant difference in the number of unit heads adjacent to the pre-processing head 5 or post-processing head 6 among these unit heads, the ink ejection characteristics of the unit heads may differ significantly. This embodiment describes an example head configuration that reduces this difference in the number of adjacent unit heads.

[0139] Figure 14A This is a top view schematically showing a carriage 3H-1 having a head arrangement according to Example 9. The carriage 3H-1 has a head arrangement such that, when the number of two unit heads (same-color ink heads) included in each of the first to sixth ink heads 4A to 4F adjacent to the pre-processing head 5 or the post-processing head 6 in the main scanning direction S and the transport direction F is counted, the difference between the maximum and minimum count values ​​is 1 or less.

[0140] The head configuration of carriage 3H-1 is the same as above Figure 13 The carriage 3G shown has the same head configuration. Focusing on the fifth ink head 4E, as described above, when counting the processing heads 5 and 6 adjacent to the upstream head 4E1 in the main scanning direction S and the transport direction F, there are two (maximum) counts: the pre-processing head 5 and the first post-processing head 6A. On the other hand, there is only one (maximum) count adjacent to the downstream head 4E2: the first post-processing head 6A. Therefore, the difference between the maximum and minimum counts is 1, satisfying the aforementioned requirements.

[0141] Similarly, focusing on the sixth ink head 4F, the count value for the processing heads 5 and 6 adjacent to the upstream head 4F1 is 2 (the minimum value), while the count value for the downstream head 4F2 is 3 (the maximum value), and the difference between the two is also 1. On the other hand, for the first to fourth ink heads 4A to 4D, since there are no adjacent processing heads 5 and 6, the count values ​​are all "0." Therefore, the difference between the maximum and minimum values ​​is all "0," satisfying the above requirements.

[0142] Figure 14B This is a top view schematically showing a carriage 3H-2 having a head arrangement according to another example of Example 9. The arrangement of the first to sixth ink heads 4A to 4F on the carriage 3H-2 is similar to that of the first to sixth ink heads 4A to 4F. Figure 14A The pre-processing head 5 includes first and second pre-processing heads 5A and 5B arranged in the main scanning direction S with the upstream head 4C1 of the third ink head 4C interposed therebetween. The post-processing head 6 includes first and second post-processing heads 6A and 6B arranged in the main scanning direction S with the downstream head 4C2 interposed therebetween.

[0143] In the second ink head 4B of carriage 3H-2, the count values ​​of the processing heads 5 and 6 adjacent to the upstream head 4B1 and the downstream head 4B2 are 2 and 1, respectively, with a difference of 1. In the third ink head 4C, the count values ​​of the upstream head 4C1 and the downstream head 4C2 are both 3, with a difference of 0. In the fourth ink head 4D, the count value of the upstream head 4D1 is 1, and the count value of the downstream head 4D2 is 2, with a difference of 1. The count values ​​of the remaining ink heads 4A, 4E, and 4D are all 0. Therefore, for all of the first to sixth ink heads 4A to 4F, the difference between the maximum and minimum values ​​is 1 or less, satisfying the above requirements.

[0144] As described above, in Example 9, the difference between the maximum and minimum count values ​​of the upstream heads 4A1 to 4F1 and the downstream heads 4A2 to 4F2 of the first to sixth ink heads 4A to 4F adjacent to the processing heads 5 and 6, respectively, is 1 or less. This prevents significant variations in ink ejection volume between multiple ink heads of the same color.

[0145] Figure 14C This is a top view schematically showing a carriage 3H-3 equipped with a head arrangement according to a comparative example (within the scope of the present invention) for Example 9. Carriage 3H-3 includes first to sixth ink heads 4A to 4F. However, unlike carriages 3H-1 and 3H-2 described above, the upstream heads 4A1 to 4F1 are arranged sequentially from left to right, while the downstream heads 4A2 to 4F2 are arranged in the opposite direction. The pre-processing head 5 and the first and second post-processing heads 6A and 6B are arranged in the same positions as in carriage 3H-1.

[0146] In carriage 3H-3, focusing on the first ink head 4A, the count value of the processing heads 5 and 6 adjacent to its upstream head 4A1 is 2 (maximum), while the count value of the downstream head 4A2 is 0 (minimum), resulting in a difference of 2. In this case, the temperature difference between the upstream head 4A1 and the downstream head 4A2 during operation of the inkjet printer 1 increases, potentially leading to a significant difference in the amount of ink ejected between these heads. This can lead to differences in color tone even when the first ink head 4A, which is the same color, is ejected, which is undesirable.

[0147] <Example 10>

[0148] Figures 15A to 15C The figures are top views schematically showing carriages 3I-1, 3I-2, and 3I-3 each having a head arrangement according to Example 10. Example 10 shows an example in which the pre-processing heads 5 and post-processing heads 6 are arranged as closely together as possible on the head support frame 31, rather than being dispersed, thereby reducing contact between the pre-processing liquid and the post-processing liquid and the ink.

[0149] In Example 10, a head arrangement satisfying the following requirements (A) to (C) is exemplified.

[0150] (A) When the number of unit heads of the pre-processing head 5 and the post-processing head 6 is greater, and the number of unit heads of the post-processing head 6 is less, and the condition m=n+odd number is satisfied,

[0151] (B) the arrangement or arrangement center of the one or more pre-processing heads 5 in the main scanning direction S coincides with the arrangement or arrangement center of the one or more post-processing heads 6 in the main scanning direction S, and

[0152] (C) The arrangement or arrangement center of the pre-processing head 5 and the post-processing head 6 coincides with the arrangement position of one of the ink heads 4 in the main scanning direction S.

[0153] Furthermore, the head configuration of Example 10 satisfies the following requirement (D).

[0154] (D) The arrangement or arrangement center of the pre-processing head 5 and the post-processing head 6 coincides with the arrangement position of the m-th ink head row from the end in the main scanning direction S.

[0155] Here, a row is a unit that summarizes the heads arranged along the transport direction F. The m-th row of ink heads from the end in the main scanning direction S refers to the row of ink heads 4 that is the m-th row from the end of the head arrangement in the head arrangement of the ink heads 4. By also satisfying the aforementioned requirement (D), the pre-processing heads 5 and post-processing heads 6 can be arranged in a concentrated state close to the end in the main scanning direction S of the ink heads 4. This reduces the likelihood of the pre-processing and post-processing liquids coming into contact with the ink on the carriage.

[0156] Figure 15A The carriage 3I-1 shown includes an ink head 4, a pre-processing head 5, and a post-processing head 6 having a first and a second post-processing head 6A, 6B. Figure 13 The same as others. In the case of this example, there are m=2 post-processing heads 6 and n=1 pre-processing head 5. Therefore, m=n+odd number that satisfies the above requirement (A). In addition, the configuration center of the pre-processing head 5 and the arrangement center of the post-processing head 6 are both the center C in the figure, which also satisfies the above requirement (B). Moreover, the center C is consistent with the configuration position of the downstream side head 4F2 of the sixth ink head 4F, which also satisfies the above requirement (C). Moreover, the downstream side head 4F2 is the head of the second row of ink heads from the right end, which also satisfies the above requirement (D).

[0157] Figure 15B The carriage 3I-2 shown includes an ink head 4, a pre-processing head 5 having a first and a second pre-processing head 5A, 5B, and a post-processing head 6 having a first, a second and a third post-processing head 6A, 6B, 6C. In the case of this example, there are m=3 post-processing heads 6 and n=2 pre-processing heads 5. Therefore, m=n+odd number, which satisfies the above requirement (A). In addition, the arrangement centers of the pre-processing heads 5 and the post-processing heads 6 are both the center C in the figure, which also satisfies the above requirement (B). Moreover, the center C is consistent with the configuration position of the upstream side head 4E1 of the fifth ink head 4E, which also satisfies the above requirement (C). Moreover, the upstream side head 4E1 is the head of the third row of ink heads from the right end, which also satisfies the above requirement (D).

[0158] Figure 15C The carriage 3I-3 shown includes an ink head 4, a pre-processing head 5, and a post-processing head 6 having a first, second, third, and fourth post-processing heads 6A, 6B, 6C, and 6D. In the case of this example, there are m=4 post-processing heads 6 and n=1 pre-processing head 5. Therefore, m=n+odd number, which satisfies the above requirement (A). In addition, the arrangement center of the pre-processing head 5 and the arrangement center of the post-processing head 6 are both the center C in the figure, which also satisfies the above requirement (B). Moreover, the center C is consistent with the arrangement position of the downstream side head 4E2 of the fifth ink head 4E, which also satisfies the above requirement (C). Moreover, the downstream side head 4E2 is the head of the fourth row of ink heads from the right end, which also satisfies the above requirement (D).

[0159] Figure 15DThis is a top view schematically showing a carriage 3I-4 equipped with a head configuration according to a comparative example (within the scope of the present invention) for Example 10. The carriage 3I-4 includes an ink head 4, a pre-processing head 5 comprising first and second pre-processing heads 5A and 5B, and a post-processing head 6 comprising first, second, and third post-processing heads 6A, 6B, and 6C. This comparative example satisfies the aforementioned requirement (A) of m = n + an odd number. However, the arrangement center C1 of the pre-processing head 5 and the arrangement center C2 of the post-processing head 6 are offset in the main scanning direction S, failing to satisfy the aforementioned requirement (B). Consequently, requirement (C) is also not satisfied.

[0160] The head arrangement of Example 10 allows the pre-processing heads 5 and post-processing heads 6 to be mounted on the carriages 3I-1 to 3I-3 in a somewhat concentrated manner. This reduces the number of ink heads 4A to 4F positioned near the pre-processing heads 5 or post-processing heads 6. This reduces the likelihood of pre-processing and post-processing liquids coming into contact with ink on the carriage.

[0161] For example, compare the carriage 3I-2, where m and n are the same number, with the carriage 3I-4 of the comparative example. In the comparative example, the first and second post-processing heads 6A and 6B are offset by one pitch in the main scanning direction S compared to the example. Therefore, in the comparative example, the number of ink heads 4 adjacent to the first to third post-processing heads 6A to 6C increases. Consequently, the likelihood of ink contacting the post-processing liquid is greater than in the example, making this undesirable.

[0162] <Example 11>

[0163] In Embodiment 11, a preferred arrangement relationship between the heads 4 , 5 , and 6 on the carriage and the sub-tanks that supply ink or processing liquid thereto is exemplified. Figure 16 This is a top view showing a carriage 3J and a sub-tank arrangement having a head arrangement according to Example 11. The carriage 3J includes an ink head 4 having first to sixth ink heads 4A to 4F, a pre-processing head 5, and a post-processing head 6 having first and second post-processing heads 6A and 6B. Figure 13 and the same as others.

[0164] The carriage 3J also carries auxiliary tanks 7. The auxiliary tanks 7 include ink auxiliary tanks 7A to 7F, a pre-treatment liquid auxiliary tank 71, and a post-treatment liquid auxiliary tank 72. Ink, pre-treatment liquid, and post-treatment liquid are supplied to these auxiliary tanks 7 from a main tank (not shown). The ink auxiliary tanks 7A to 7F supply the ink to the first to sixth ink heads 4A to 4F, respectively. For example, first color ink is supplied from the first tank 7A1 of the ink auxiliary tank 7A via pipe P1 to the upstream head 4A1 of the first ink head 4A, and from the second tank 7A2 via pipe P1 to the downstream head 4A2. The second to sixth ink heads 4B to 4F are similarly supplied with ink of the second to sixth colors, respectively. The arrangement order of the ink auxiliary tanks 7 in the main scanning direction S is the same as the arrangement order of the ink heads 4 to which the ink auxiliary tanks 7 supply ink.

[0165] Alternatively, ink can be supplied from a single ink sub-tank 7 to multiple ink heads 4 that eject ink of the same color. In this case, the ink heads 4 that share the ink sub-tank 7 can be arranged at a concentrated position in the main scanning direction S. Furthermore, it is preferable to arrange the ink heads 4 that eject the same ink in a concentrated manner in the main scanning direction S. In the main scanning direction S, the arrangement order of the ink sub-tanks 7 for each color can be the same as the arrangement order of the ink heads 4 for each color.

[0166] The pre-treatment liquid sub-tank 71 supplies the pre-treatment liquid to the pre-treatment head 5 via the pipe P2. The post-treatment liquid sub-tank 72 includes a first tank 72A and a second tank 72B. The first and second tanks 72A and 72B supply the post-treatment liquid to the first and second post-treatment heads 6A and 6B, respectively, via the pipe P3.

[0167] The ink sub-tanks 7A to 7F are mounted on the carriage 3J so as to be aligned along the main scanning direction S. The treatment liquid sub-tanks 71 and 72 are arranged along the main scanning direction S at positions different from those of the ink sub-tanks 7A to 7F in the conveyance direction F. Specifically, the first and second tanks 72A and 72B of the pre-treatment liquid sub-tank 71 and the post-treatment liquid sub-tank 72 are arranged in a row along the main scanning direction S, downstream of the ink sub-tanks 7A to 7F in the conveyance direction F. Alternatively, only the pre-treatment liquid sub-tank 71 may be arranged upstream of the ink sub-tanks 7A to 7F.

[0168] The liquid in the sub-tank 7, mounted on the carriage 3J, which reciprocates in the main scanning direction S, is subjected to acceleration in the main scanning direction S. The sub-tank 7 is connected to the heads 4, 5, and 6 via pipes P1, P2, and P3. However, if the sub-tank 7 is widely distributed on the carriage 3J, the arrangement range of the pipes P1 to P3 in the main scanning direction S also increases. Because these pipes P1 to P3 are also filled with ink or processing liquid, the acceleration may cause meniscus breakdown in the ejection area of ​​the heads 4, 5, and 6.

[0169] However, according to the configuration of Example 11, the ink sub-tanks 7A to 7F, like the first to sixth ink heads 4A to 4F, are mounted on the carriage 3J so as to be aligned along the main scanning direction S. Therefore, the ink sub-tanks 7A to 7F can be arranged in a relatively narrow area on the head support frame 31 of the carriage 3J. Similarly, the pre-treatment liquid sub-tank 71 and the post-treatment liquid sub-tank 72 can also be arranged in a relatively narrow area on the head support frame 31 of the carriage 3J.

[0170] Furthermore, the pre-treatment liquid sub-tank 71 and the post-treatment liquid sub-tank 72 are positioned differently from the ink sub-tanks 7A to 7F in the transport direction F. Consequently, the positions of the pre-treatment liquid sub-tank 71 and the post-treatment liquid sub-tank 72 and the treatment heads 5 to which they supply treatment liquid can be arranged so that the positional difference in the main scanning direction S between them is minimal. Consequently, the distribution range of the pre-treatment liquid in the interconnected pre-treatment liquid sub-tank 71, the pipeline P, and the pre-treatment head 5 in the main scanning direction S can be reduced, making them less susceptible to the effects of the aforementioned acceleration. Similarly, the distribution range of the interconnected post-treatment liquid in the main scanning direction S can be reduced, making them less susceptible to the effects of the aforementioned acceleration.

[0171] Similarly, the positional differences between the ink sub-tanks 7A to 7F and the ink heads 4 to which they supply ink can be reduced in the main scanning direction S. This reduces the distribution range of the ink in the main scanning direction S, making it less susceptible to the acceleration.

[0172] [Summary of the Invention]

[0173] An inkjet recording device according to one aspect of the present invention includes: a conveying portion that conveys a recording medium along a prescribed conveying direction; a carriage that reciprocates along a main scanning direction intersecting the conveying direction; a plurality of ink heads that are mounted on the carriage in an arrangement along the main scanning direction and eject ink for image formation; and a plurality of processing heads that are mounted on the carriage and eject a non-colored processing liquid, wherein the plurality of processing heads are arranged in positions different from the ink heads in the conveying direction and are arranged along the main scanning direction.

[0174] According to this inkjet recording device, since the processing head is arranged at a different position from the ink head in the conveying direction, it is possible to ensure the desired landing order of the processing liquid and the ink on the recording medium in both the forward and reverse movements of the carriage. Assuming that a structure is adopted in which the processing head and the ink head are arranged at the same position in the conveying direction, in order to ensure the landing order, the processing heads need to be arranged on both sides of the ink head group. In this case, the width of the carriage in the main scanning direction becomes larger. According to the structure of the present invention, since such a configuration is not required, the width of the carriage in the main scanning direction can be miniaturized. In addition, a plurality of processing heads are arranged along the main scanning direction. Therefore, even in the case where the ejection amount of the processing liquid is insufficient in a single unit, the necessary ejection amount can be ensured by the configuration of a plurality of processing heads.

[0175] In the above-described inkjet recording apparatus, the plurality of ink heads may be arranged in a direction intersecting with an arrangement direction of the plurality of processing heads.

[0176] According to this inkjet recording device, the multiple ink heads are arranged in a direction intersecting the arrangement direction of the multiple processing heads (the main scanning direction). Therefore, even if the number of ink heads is increased to increase the ink ejection volume or to achieve multi-color printing, the width of the carriage in the main scanning direction can be reduced.

[0177] In the inkjet recording apparatus, the plurality of processing heads may be arranged within a range of an arrangement width of the plurality of ink heads in the main scanning direction.

[0178] According to this inkjet recording apparatus, even when the processing head is mounted on the carriage, there is no need to increase the width of the carriage in the main scanning direction.

[0179] In the inkjet recording apparatus, the processing head may be arranged so that a portion of the processing head enters between a pair of ink heads adjacent to each other in the main scanning direction.

[0180] According to this inkjet recording apparatus, ink heads and processing heads arranged at different positions in the transport direction (sub-scanning direction) can be arranged at high density in the transport direction, thereby miniaturizing the width of the carriage in the transport direction.

[0181] In the inkjet recording device, the processing head can also be arranged in such a manner that a part of the processing head is adjacent to the ink head in the main scanning direction and the conveying direction, and the multiple ink heads include multiple same-color ink heads that eject ink of the same color, and when the number of adjacent processing heads is counted for each of the same-color ink heads, the difference between the maximum and minimum values ​​of their count values ​​is less than 1.

[0182] Typically, heads that eject liquid using a jetting method generate heat because they use electricity to pressurize the liquid. In particular, unlike ink heads that eject only when forming dots of a desired color, processing heads that eject for all colors are more likely to reach high temperatures. Ink heads adjacent to such processing heads are more likely to reach high temperatures, resulting in differences in ink ejection volume compared to ink heads not adjacent to the processing heads. As described above, by setting the difference between the maximum and minimum counts for each ink head of the same color adjacent to the processing head to less than 1, significant differences in ink ejection volume between multiple ink heads of the same color are less likely to occur.

[0183] In the inkjet recording device, the processing head can also be arranged in such a manner that a part of the processing head is adjacent to the ink head in the main scanning direction and the conveying direction, and the multiple ink heads include at least a first ink head that ejects ink of a first color and a second ink head that ejects ink of a second color. When the number of the processing heads adjacent to the first ink head is greater than the number of the processing heads adjacent to the second ink head, an ink having a smaller viscosity change due to temperature than the ink of the second color is ejected as the ink of the first color.

[0184] According to this inkjet recording device, the first ink head, which has a larger number of adjacent processing heads, ejects ink whose viscosity changes less with temperature. Therefore, even if the first ink head is heated by the pre-processing head, changes in the ejection volume and ejection speed of the first color ink due to temperature can be reduced.

[0185] In the inkjet recording apparatus, the plurality of processing heads and the plurality of ink heads may be arranged separately in the main scanning direction.

[0186] When ink comes into contact with a treatment liquid, for example, ink components may aggregate. If the aggregates adhere to the ink ejection nozzles of the inkjet head, ejection defects may occur. With the inkjet recording device described above, since the treatment head and ink head are separated in the main scanning direction, contact between the ink and treatment liquid on the carriage can be minimized.

[0187] The inkjet recording device includes: a pre-processing head arranged on the upstream side of the ink head in the conveying direction and a post-processing head arranged on the downstream side, wherein at least one of the pre-processing head and the post-processing head is the multiple processing heads arranged in the main scanning direction.

[0188] This configuration provides a multifunctional, all-in-one inkjet recording device in which the heads for discharging the pre-treatment liquid, ink, and post-treatment liquid are all mounted on a single carriage. Furthermore, because the pre-treatment head, ink head, and post-treatment head are sequentially arranged in the conveyance direction, the desired order in which the pre-treatment liquid, ink, and post-treatment liquid land on the recording medium can be ensured. Furthermore, because at least one of the pre-treatment head and post-treatment head is aligned along the main scanning direction, the desired discharge volume of the pre-treatment liquid and post-treatment liquid can be ensured.

[0189] In the inkjet recording device, the carriage may include a first area where the plurality of ink heads are arranged and a second area adjacent to the first area in the main scanning direction, and the pre-processing head and the post-processing head are arranged in the second area.

[0190] According to this inkjet recording device, the pre-processing head, post-processing head, and ink head can be separated in the main scanning direction, thereby making it difficult for the pre-processing liquid and post-processing liquid to come into contact with the ink on the carriage, thereby reducing problems such as aggregation.

[0191] In the inkjet recording apparatus, the pre-processing head and the post-processing head may be arranged in a central area of ​​an arrangement width of the plurality of ink heads in the main scanning direction.

[0192] Alternatively, the pre-processing heads and the post-processing heads may be arranged so that the arrangement or arrangement center of one or more pre-processing heads in the main scanning direction coincides with the arrangement or arrangement center of one or more post-processing heads in the main scanning direction.

[0193] According to these inkjet recording apparatuses, it is possible to reduce variations in the time from when the pre-treatment liquid lands on the recording medium to when the ink lands, and in the time from when the ink lands to when the post-treatment liquid lands, at each main scanning position.

[0194] In the inkjet recording device, it can also be: assuming that the number of the pre-processing heads and the post-processing heads is m, and the number of the heads is n, the requirement of m=n+odd number is satisfied, the configuration or arrangement center of one or more of the pre-processing heads in the main scanning direction is consistent with the configuration or arrangement center of one or more of the post-processing heads in the main scanning direction, and the configuration or arrangement center of the pre-processing heads and the post-processing heads is consistent with the configuration position of one of the multiple ink heads in the main scanning direction.

[0195] This inkjet recording device allows the pre-processing head and post-processing head to be mounted on the carriage in a somewhat centralized manner. This reduces the number of inkjet heads positioned close to the processing heads. This reduces the likelihood of pre-processing and post-processing liquids coming into contact with the ink on the carriage.

[0196] The inkjet recording device may also include: a holding component that holds the slide in a state where it can move back and forth along the main scanning direction, wherein the slide includes a locking portion that is held by the holding component in a cantilever state, and in the conveying direction, the front processing head is arranged on the side of the locking portion relative to the post-processing head.

[0197] According to this inkjet recording device, the carriage is supported in a cantilevered configuration by a retaining member, thereby enabling a simple structure. Furthermore, by supporting the carriage in a cantilevered configuration, a single-sided structure with the carriage exposed can be easily configured, facilitating maintenance of the inkjet head and processing head. When the carriage is supported in a cantilevered configuration, height accuracy is likely to decrease on the side of the carriage away from the engaging portion. However, since the post-processing head, which has relatively high requirements for ejection accuracy, is mounted on the side away from the engaging portion, this is unlikely to significantly impact image quality.

[0198] The inkjet recording device may also include: a holding component that holds the slide in a state where it can move back and forth along the main scanning direction, wherein the slide includes a portion that is held by the holding component in a cantilever state, and the side with fewer heads among the pre-processing head and the post-processing head is arranged on the side of the engaging portion of the slide.

[0199] As mentioned above, the treatment head generates heat during the ejection operation. Consequently, the carriage carrying the treatment head is heated, potentially causing thermal deformation of the carriage and its retaining structure. In a configuration where the carriage is held in a cantilevered position, this thermal deformation can sometimes affect ink placement accuracy. This configuration reduces the number of treatment heads positioned near the base end, minimizing the effects of thermal deformation.

[0200] The inkjet recording device may also include: a holding component that holds the slide in a state where it can move back and forth along the main scanning direction, wherein the slide includes a locking portion that is held by the holding component in a cantilever state, and the ink head and the processing head that are arranged on the side of the locking portion closest to the slide are arranged in a position other than the end of the main scanning direction in the arrangement body of the ink head and the processing head.

[0201] According to this inkjet recording device, the head positioned closest to the engaging portion is not positioned within the array of ink heads and processing heads except at the end in the main scanning direction. Generally, the end in the main scanning direction is closest to the end (corner) of the carriage. If thermal deformation occurs near the end of the carriage, i.e., the base end, the positional accuracy of the head mounted on the carriage decreases. This configuration minimizes this problem.

[0202] The inkjet recording device may also include: an ink sub-tank for supplying the ink to each of the multiple ink heads; and a treatment liquid sub-tank for supplying the treatment liquid to each of the multiple treatment heads, wherein the ink sub-tank is mounted on the slide in a manner arranged along the main scanning direction, and the treatment liquid sub-tank is arranged in a position different from the ink sub-tank in the conveying direction and is arranged along the main scanning direction.

[0203] According to the above configuration, the ink sub-tanks and the processing head sub-tanks are arranged along the main scanning direction at different positions along the transport direction than the heads. This allows the sub-tanks to be arranged within a relatively narrow range on the carriage. Furthermore, the liquid in the sub-tanks, carried on the carriage as it reciprocates along the main scanning direction, is subjected to acceleration in the main scanning direction. The sub-tanks are connected to the heads via prescribed conduits. However, if the sub-tanks are widely distributed on the carriage, the conduit arrangement range in the main scanning direction also increases, thus increasing the effect of the acceleration and potentially causing meniscus rupture in the ejection portion of the head. According to the above configuration, the conduit arrangement range in the main scanning direction can be relatively narrow.

[0204] According to the present invention described above, it is possible to provide an inkjet recording apparatus that can achieve miniaturization of the carriage and ensure the necessary ejection amounts of ink and processing liquid.

[0205] Explanation of symbols

[0206] 1 Inkjet printer (ink head recording device)

[0207] 16 Timing belt (moving part)

[0208] 17 Guide rail (holding component)

[0209] 20 Workpiece conveying unit (conveying unit)

[0210] 3. 3A to 3J carriages

[0211] 31 Head support frame 31

[0212] 32 rear frame (locking part)

[0213] 4 ink heads

[0214] 4A to 4F: First to sixth ink heads

[0215] 4A1 to 4F1 upstream side head

[0216] 4A2 to 4F2 downstream side head

[0217] 5. Pre-processing head (processing head)

[0218] 6 Post-processing head (processing head)

[0219] 7 secondary containers

[0220] 7A to 7F ink sub-tanks

[0221] 71 Auxiliary container for pretreatment liquid

[0222] 72 Auxiliary container for post-processing liquid

[0223] F Conveying direction

[0224] S Main scanning direction

[0225] W Workpiece (recording medium)

Claims

1. An inkjet recording device, characterized in that include: a conveying unit for conveying the recording medium in a prescribed conveying direction; a carriage reciprocating along a main scanning direction intersecting the conveying direction; a plurality of ink heads mounted on the carriage in an array along the main scanning direction and ejecting ink for image formation; and A plurality of processing heads are mounted on the carriage and eject non-colored processing liquid, wherein The plurality of processing heads are arranged in a row along the main scanning direction at positions different from the ink head in the conveying direction. The plurality of processing heads are arranged within a range of an arrangement width of the plurality of ink heads in the main scanning direction.

2. The inkjet recording device according to claim 1, wherein The plurality of ink heads are also arranged in a direction intersecting the main scanning direction.

3. The inkjet recording device according to claim 1 or 2, wherein The processing head and the ink head have an overlapping area in a direction intersecting the main scanning direction.

4. The inkjet recording device according to claim 1 or 2, wherein The processing head is arranged so that a portion of the processing head is adjacent to the ink head in the main scanning direction and the conveying direction. The plurality of ink heads include a plurality of ink heads of the same color that eject ink of the same color, When the number of adjacent processing heads is counted for each of the same-color ink heads, the difference between the maximum and minimum count values ​​is 1 or less.

5. The inkjet recording device according to claim 1 or 2, wherein The processing head is arranged so that a portion of the processing head is adjacent to the ink head in the main scanning direction and the conveying direction. The plurality of ink heads include at least a first ink head for ejecting ink of a first color and a second ink head for ejecting ink of a second color. When the number of the processing heads adjacent to the first ink head is greater than the number of the processing heads adjacent to the second ink head, ink having a smaller viscosity change due to temperature than the second color ink is ejected as the first color ink.

6. The inkjet recording device according to claim 1 or 2, wherein: The plurality of processing heads and the plurality of ink heads are arranged separately in the main scanning direction.

7. The inkjet recording device according to claim 1 or 2, characterized in that Include: A pre-processing head is arranged on the upstream side of the ink head in the conveying direction, and a post-processing head is arranged on the downstream side, wherein: At least one of the pre-processing head and the post-processing head is the plurality of processing heads arranged side by side in the main scanning direction.

8. The inkjet recording device according to claim 7, wherein The pre-processing head and the post-processing head are arranged in a central area of ​​an arrangement width of the plurality of ink heads in the main scanning direction.

9. The inkjet recording device according to claim 7, wherein The pre-processing heads and the post-processing heads are arranged such that the arrangement or arrangement center of one or more pre-processing heads in the main scanning direction coincides with the arrangement or arrangement center of one or more post-processing heads in the main scanning direction.

10. The inkjet recording device according to claim 7, wherein Assuming that the number of the pre-processing heads and the post-processing heads is greater, m, and the number of the post-processing heads is less, n, and the condition of m=n+odd number is satisfied, The arrangement or arrangement center of one or more of the front processing heads in the main scanning direction is consistent with the arrangement or arrangement center of one or more of the post-processing heads in the main scanning direction, and, The arrangement or arrangement center of the pre-processing head and the post-processing head coincides with the arrangement position of one of the plurality of ink heads in the main scanning direction.

11. The inkjet recording device according to claim 7, wherein Also includes: A holding member holds the carriage in a state where the carriage can reciprocate along the main scanning direction, wherein The slide includes an engaging portion held by the holding member in a cantilevered state. The pre-processing head is arranged on the engaging portion side relative to the post-processing head in the transport direction.

12. The inkjet recording device according to claim 7, wherein Also includes: A holding member holds the carriage in a state where the carriage can reciprocate along the main scanning direction, wherein The slide includes an engaging portion held by the holding member in a cantilevered state. The pre-processing head and the post-processing head, whichever has a smaller number of heads, is arranged on the engaging portion side of the carriage.

13. The inkjet recording device according to claim 1 or 2, characterized in that Also includes: A holding member holds the carriage in a state where the carriage can reciprocate along the main scanning direction, wherein The slide includes an engaging portion held by the holding member in a cantilevered state. The ink head and the processing head, whichever is located closest to the engaging portion of the carriage, is arranged at a position other than an end in the main scanning direction in the array of the ink head and the processing head.

14. The inkjet recording device according to claim 1 or 2, characterized in that Also includes: an ink sub-tank for supplying the ink to each of the plurality of ink heads; and The processing liquid auxiliary tank supplies the processing liquid to each of the plurality of processing heads, wherein The ink sub-tanks are mounted on the carriage so as to be aligned in the main scanning direction, and the processing liquid sub-tanks are arranged in the main scanning direction at positions different from the ink sub-tanks in the transport direction.

Images