Image formation method for inkjet printers

Abstract

To provide an image formation method of an inkjet printer that can shorten a processing time and reduce loss of media, without deteriorating an image quality.SOLUTION: An image formation method of an inkjet printer, which is provided with an ink head that jets ink to media and a spray head that sprays a liquid agent, performs a printing process of making the ink head jet ink and, in addition, performs steps of: creating a job list in which "presence" or "absence" of a spraying process of making the spray head spray the liquid agent is set as a parameter; grouping a plurality of jobs including a common parameter in the job list; and executing the job for each group.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to an image forming method for an inkjet printer capable of printing an image by ejecting ink onto a medium and performing a coating process by spraying a treatment agent.

Background Art

[0002] An inkjet printer is an apparatus that prints an image by reciprocating an ink head that ejects ink in the width direction (scanning direction) of a medium such as recording paper. When printing an image on a medium made of a material on which ink is difficult to fix, such as acrylic resin or glass, a coating treatment for forming a coating layer on the surface of the medium is performed by spraying a pretreatment agent (primer) or a post-treatment agent (top coating agent) onto the surface of the medium before or after printing. When the above coating treatment is performed by a user, it is necessary to spray the pretreatment agent or post-treatment agent onto the medium and coat the surface of the medium before setting the medium before image printing on the inkjet printer, or after removing the medium with the printed image from the inkjet printer, which requires a great deal of labor and time from the user.

[0003] Accordingly, it is conceivable to provide an inkjet printer with an ink head that ejects printing ink and a spray head that sprays a treatment agent (a pretreatment agent or a post-treatment agent) arranged side by side. When, for example, two jobs A and B for spraying a pretreatment agent for surface treatment before printing as shown in Fig. 5 are executed on one medium in an inkjet printer adopting such a configuration, in the preceding job A, the pretreatment agent is sprayed from the spray head H1 onto the surface of the medium m to form the coating layer 10. Then, after that, ink is ejected from the ink head H2, required printing is performed on the coating layer 10 of the medium m, and an image 20 is formed on the coating layer 10.

[0004] Then, in job B, which is executed following job A, a pre-treatment agent for surface preparation is first sprayed from the spray head H1 toward the surface of media m, forming a coating layer 11 on the surface of media m. However, at this time, some of the sprayed pre-treatment agent does not adhere to the surface of media m but is scattered into the surroundings as a mist, adhering to the image 20 formed on media m in the previous job A, which degrades the quality of the image 20.

[0005] To solve the above problem, possible solutions include ensuring sufficient printing intervals between jobs A and B, or printing only one job's image per medium. However, such solutions result in significant loss of time and media.

[0006] Furthermore, the same problems described above occur when a post-treatment agent is sprayed onto the surface of the media after printing. In other words, when a job in which a post-treatment agent is sprayed onto the media after printing is followed by a similar job, some of the post-treatment agent sprayed in the previous job will scatter as mist, and this mist will adhere to the surface of the media m on which the next job is performed, impairing the adhesion of the print ink to the media.

[0007] Incidentally, in inkjet printers equipped with both an ink head and a spray head, if, for example, there is a mix of jobs that perform both printing by ink jetting and coating by spraying a processing agent, and jobs that perform only one of these, or if there is a mix of jobs that perform coating before printing (pre-processing) and jobs that perform coating after printing (post-processing), then executing a series of jobs can lead to problems such as increased processing time and greater media loss, depending on the order in which the jobs are executed.

[0008] From the perspective of shortening processing time (throughput time), Patent Document 1 proposes an image forming apparatus that performs a coating process to form a film. In this image forming apparatus, if there are uncoated pages before the coated pages detected by the detection unit in the image data in the order of discharge, the modification unit performs a modification process to change the image formation order of the image data of the coated pages so that images are formed before the uncoated pages. The image forming unit then performs image formation in the image formation order modified by the modification unit, and the transport control unit controls the transport of the recording sheets that have been image formed and coated in the image processing order by the image forming unit. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Japanese Patent Publication No. 2013-145306 [Overview of the project] [Problems that the invention aims to solve]

[0010] However, the technology disclosed in Patent Document 1 reverses the image formation order as a countermeasure when there are uncoated pages before coated pages. Therefore, it cannot function in situations where printing targets that undergo spray treatment before or after printing are mixed on the media mounting surface, that is, in situations where spray treatment is present or absent within a single printing process of an inkjet printer.

[0011] The present invention has been made in view of the above circumstances, and its purpose is to provide an image forming method for an inkjet printer that can shorten processing time and reduce media loss without compromising image quality. [Means for solving the problem]

[0012] To solve the above problems, the image forming method for an inkjet printer according to claim 1 is: An image forming method for an inkjet printer, comprising an ink head for ejecting ink onto media and a spray head for spraying a liquid agent, A job list is created with the parameter whether there is a "yes" or "no" spray process in which the liquid agent is sprayed from the spray head, in addition to the printing process in which the ink is ejected from the ink head. In the aforementioned job list, multiple jobs containing common parameters are grouped together. A key feature is that jobs are executed for each group.

[0013] With the above configuration, multiple jobs are grouped in the job list using the presence or absence of spray processing as a parameter, allowing jobs in each grouped group to be processed together in the image formation process. In other words, by executing each group based on whether or not spray processing is performed, even when printing multiple image processing steps in a single processing step, it is possible to avoid the scattering of spray mist onto media that does not require spray processing. Specifically, since multiple images on the media placed on the loading stage during the image formation process are divided into those that will be sprayed and those that will not, the timing of spray processing can be consolidated into one step. Therefore, images printed in jobs executed before and after are not adversely affected by the mist of the processing agent scattered, ensuring high image quality.

[0014] Furthermore, by executing multiple grouped jobs as a group, processing time can be reduced compared to running each job individually, and media loss can be minimized. In addition, by combining multiple jobs into a single group, unnecessary setup operations can be eliminated, which also reduces processing time. [Effects of the Invention]

[0015] According to the present invention, it is possible to print images using both ink jetting and liquid spraying methods, and when printing multiple images using both methods, it is possible to shorten processing time and reduce media loss without compromising image quality. This achieves improved quality and faster processing in increasingly diverse and high-volume image printing. [Brief explanation of the drawing]

[0016] [Figure 1] This figure shows an example of a job list according to an embodiment of the present invention. [Figure 2] This figure shows an example of a list of job parameters according to an embodiment of the present invention. [Figure 3] Figures (a) to (c) show an example of how a job list can be grouped according to an embodiment of the present invention. [Figure 4] This figure shows an example of an image printing layout on media according to an embodiment of the present invention. [Figure 5] This diagram illustrates the problems with conventional image formation methods. [Modes for carrying out the invention]

[0017] Embodiments of the present invention will be described below with reference to the accompanying drawings.

[0018] An inkjet printer (not shown) in which the method of the present invention is implemented is an apparatus that performs printing by reciprocating an ink head H2 (see FIG. 5) that ejects ink in the width direction (main scanning direction) of a medium m such as recording paper (see FIG. 5). In addition to the ink head H2, the printer includes a spray head H1 (see FIG. 5) that performs a coating process of forming a coating layer on the surface of the medium m by spraying a treatment agent onto the medium m. The treatment agent is supplied to the spray head H1 from a treatment agent tank (not shown), and compressed air is supplied from an air compressor (not shown). The treatment agent supplied to the spray head H1 is atomized by the compressed air supplied to the spray head H1 and sprayed from a spray nozzle of the spray head H1. A plurality of spray heads H1 may be provided corresponding to the number of types of treatment agents. Alternatively, the printer may be configured to include a mechanism that switches the treatment agent supplied to one spray head H1. Here, the ink head H2 and the spray head H1 are mounted on an unillustrated carriage that reciprocates in the width direction of the medium m, and are configured to be capable of independently scanning the medium m respectively. The medium m is subjected to processes such as printing and coating for various images while being placed on a mounting table provided in the inkjet printer.

[0019] In the present embodiment, when performing a coating process, if the type (material) of the medium, for example, the medium is made of materials such as vinyl chloride resin, acrylic resin, glass, artificial leather, it is determined depending on the type of the medium whether to perform the coating process, and further whether to perform the coating process before or after printing an image on the medium by the ink head. For example, pretreatment is applied to acrylic resin, glass and the like, and post-treatment is applied to artificial leather and the like. This is an example, and the present invention is not limited thereto. Hereinafter, the coating process performed before printing an image is referred to as "pre-processing", and the coating process performed after printing an image is referred to as "post-processing". In pre-processing, a primer is used as a treatment agent, and in post-processing, a top coating agent is used as a treatment agent.

[0020] When forming a desired image on a medium using such an inkjet printer (spray-and-print machine), a user creates job data by inputting necessary information. Here, as job data, data such as print image data, the type of medium, the presence or absence of coating treatment, the timing of performing coating treatment (before or after printing), and image size are input for each job.

[0021] The input of job data by the user is performed through selection operations and setting operations on a display operation unit of a computer connected to the printer main body (for example, a display screen on a display of a printer driver, a keyboard, a pointing device, etc.). Therefore, the user can arbitrarily set the timing for performing the coating treatment. Note that the input of job data may be performed through selection operations and setting operations on a display operation unit mounted on the printer main body (for example, a liquid crystal screen and operation keys mounted on the printer main body, or a touch panel).

[0022] Furthermore, if the user inputs the media type, the necessity and timing (before or after printing) of the coating process may be automatically determined by a computer connected to the printer or by the CPU (Central Processing Unit) installed in the printer. In other words, the timing of the coating process and the type of processing agent used are predetermined based on the media type, and these timings and agent types are stored as job data in the ROM (Read Only Memory) or RAM (Random Access Memory) of the computer connected to the printer or the CPU (Central Processing Unit) installed in the printer. Therefore, the timing of the coating process and the type of processing agent are automatically set to be appropriate for the media.

[0023] As described above, once job data is entered by the user, a list of jobs the user wants to print is created on the RIP (Raster Image Processor) software installed on the computer connected to the printer. An example of a job list is shown in Figure 1. The RIP (Raster Image Processor) is a processor that converts text and image data into raster images during the prepress process. RIP processing may also be performed on the CPU (Central Processing Unit) installed in the printer itself.

[0024] As shown in Figure 1, the job list lists each job (jobs A to F) with "pre-processing," "printing," and "post-processing" as parameters, and also lists the size (width x height, in mm) of the image to be printed for each job A to F. The contents of each job A to F are as follows: 1) Job A: In Job A, only image printing is performed, and the size of the printed image is 200mm x 500mm. 2) Job B: In Job B, pre-processing is performed before printing the image. This pre-processing is done by spraying a pre-treatment agent (primer) onto the surface of the media. The size of the image to be printed after this pre-processing is 200m x 200mm. 3) Job C: In Job C, post-processing is performed after the image is printed. This post-processing is done by spraying a post-processing agent (topcoat) onto the surface of the media. The size of the image printed before this post-processing is 300mm x 300mm. 4) Job D: In Job D, pre-processing is performed before printing the image, similar to Job B. The size of the image printed after this pre-processing is 200mm x 150mm. 5) Job E: In Job E, pre-processing is performed before printing the image, similar to Jobs B and D. The size of the image printed after this pre-processing is 400mm x 200mm. 6) Job F: In Job F, just like in Job A, only image printing is performed, and the size of the printed image is 300mm x 300mm.

[0025] Here, the parameters (pre-processing, printing, post-processing) in the job list shown in Figure 1 are selected sequentially from the list of job parameters shown in Figure 2. That is, for example, in jobs A to F, the items "color printing only," "pre-processing → color printing," "color printing → post-processing," and "pre-processing → color printing → post-processing" are selected sequentially (see the job list shown in Figure 1).

[0026] By the way, the job list shown in Figure 1 contains a chaotic mix of jobs with different parameters (preprocessing, printing, postprocessing). However, in the image forming method according to the present invention, the order of jobs A to F in the job list shown in Figure 3(a) (the same as that shown in Figure 1) is rearranged as shown in Figure 3(b). That is, multiple jobs containing common parameters, specifically jobs B, D, and E containing common parameters (preprocessing → printing), are grouped together and moved to the top three rows of the job list, and jobs A, C, and F are rearranged so that they are positioned below them.

[0027] Then, as shown in Figure 3(c), jobs B, D, and E, which are grouped together, are executed first, and then jobs A, C, and F are executed individually and sequentially. In other words, the media targeted by jobs B, D, and E are placed on the mounting platform.

[0028] In printing the images in jobs B, D, and E, which are grouped together, three images of different sizes, B, D, and E, are laid out on a 450mm x 450mm medium, as shown in Figure 4, and these images are printed together. Here, the width direction (main scanning direction) in Figure 4 and the width direction (main scanning direction) in Figure 5 are the same direction, and the direction perpendicular to this direction is the front-to-back direction (secondary scanning direction). Note that the layout of these images B, D, and E on the medium is automatically performed by a computer connected to the printer or by the CPU installed in the printer.

[0029] As described above, by executing jobs B, D, and E together, which include a step of spraying a pretreatment agent (primer) onto the media as a pretreatment before printing images B, D, and E, the timing of the pretreatment agent mist scattering can be consolidated at once. This reduces the possibility that the pretreatment agent mist will adversely affect the image printed in the subsequent job (in this embodiment, job A, which does not perform a coating process), thereby ensuring high image quality.

[0030] Furthermore, by grouping jobs B, D, and E together, processing time can be reduced compared to performing them individually, and media loss can be minimized. In addition, by grouping multiple jobs B, D, and E into one, unnecessary setup operations can be eliminated, which also reduces processing time.

[0031] Furthermore, in this embodiment, as described above, the ink head and spray head are configured to scan the media independently. Therefore, if the ink head is retracted to the home position while the treatment agent is being sprayed from the spray head, the adhesion of the mist of the sprayed treatment agent to the ink head can be suppressed, preventing problems such as clogging of the ink head.

[0032] In this embodiment, jobs B, D, and E are executed as a single group, and then jobs A, C, and F are executed individually in sequence. However, considering the time required for maintenance such as cleaning to collect mist scattered after spraying the treatment agent, it is desirable to execute jobs B, D, and E, which print after spraying the pre-treatment agent, after jobs A and F, which do not spray the treatment agent, and after job C, which sprays the post-treatment agent after printing. In other words, it is desirable to execute jobs A and F, which do not spray the treatment agent, first, then execute job C, and finally execute jobs B, D, and E together.

[0033] In this embodiment, the case where grouped jobs B, D, and E are printed on one medium and jobs A, C, and F are printed on separate media has been described. However, jobs A through F may also be printed on a single medium. In this case, it is desirable to arrange the grouped images B, D, and E in close proximity as shown in Figure 4, and to arrange images A, C, and F at a predetermined distance away from the grouped images B, D, and E.

[0034] Furthermore, in the above embodiment, jobs B, D, and E, which have "pre-processing" and "printing" as common parameters, are executed as a single group. However, jobs A and F, which have "printing" and "post-processing" as common parameters, may also be executed as a single group. In this case, it is desirable that the grouped images B, D, and E, the grouped images A and F, and image C are placed at predetermined distances from each other. Furthermore, the present invention basically creates a job list by grouping jobs with and without spray processing as parameters, thereby avoiding the mixing of jobs with and without spray processing within a single image forming process. Although examples of this level of grouping are not described in the above embodiments, it is of course possible to achieve basic effects even with grouping based solely on whether or not spray processing is present.

[0035] Furthermore, as described above, by grouping jobs based on whether or not spray processing is performed, the timing of the image formation process can be shifted, and the effects of the invention can be achieved even when print targets with and without spray processing are mixed on the loading platform by separating the job placement positions. Moreover, within the job group with spray processing, further avoidance of adverse effects from spray mist can be achieved by dividing the image regions as described above depending on whether it is a "post-processing" or "pre-processing" step.

[0036] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the technical idea described in the claims, specification, and drawings. [Explanation of symbols]

[0037] 10 images 20 Coating layers Jobs A-F (Images) H1 Spray Head H2 Inkhead m media

Claims

1. An image forming method for an inkjet printer, comprising an ink head for ejecting ink onto media and a spray head for spraying a liquid agent, A job list is created with the parameter whether there is a "yes" or "no" spray process in which the liquid agent is sprayed from the spray head, in addition to the printing process in which the ink is ejected from the ink head. The job list includes three or more jobs, including jobs where the spraying process is "included" and jobs where the spraying process is "not included". An inkjet printer image forming method characterized by grouping multiple jobs containing common parameters in the job list and executing each job for each group.

2. An image forming method for an inkjet printer, comprising an ink head for ejecting ink onto media and a spray head for spraying a liquid agent, A job list is created with the parameter whether there is a "yes" or "no" spray process in which the liquid agent is sprayed from the spray head, in addition to the printing process in which the ink is ejected from the ink head. In the aforementioned job list, multiple jobs containing common parameters are grouped together, and each job is executed for each group. The spraying process includes a pre-processing step performed before the printing process in which the ink is ejected from the ink head, and a post-processing step performed afterward. The aforementioned grouping is characterized by further dividing the grouping into those with and without spray treatment, and whether or not it is a pre-treatment or post-treatment.

3. The method for forming an image with an inkjet printer according to claim 2, characterized in that the selection of whether the spray treatment is a pre-treatment or a post-treatment is determined based on the type of media.

4. The image forming method for an inkjet printer according to claim 1, characterized in that the arrangement of the images targeted by the grouped jobs on the media is such that each group has a different arrangement area.

5. An image forming method for an inkjet printer, comprising an ink head for ejecting ink onto media and a spray head for spraying a liquid agent, A job list is created with the parameter whether there is a "yes" or "no" spray process in which the liquid agent is sprayed from the spray head, in addition to the printing process in which the ink is ejected from the ink head. In the aforementioned job list, multiple jobs containing common parameters are grouped together, and each job is executed for each group. The arrangement of the images targeted by the grouped jobs on the media is such that each group has a different arrangement area. The image formation method for an inkjet printer is characterized in that the arrangement of the aforementioned image areas is further divided and arranged according to whether the spray treatment is a pre-treatment or a post-treatment.

6. The image forming method for an inkjet printer according to claim 2, characterized in that the creation of the job list is performed by the user inputting the timing at which to execute the spraying process.

7. An image forming method for an inkjet printer, comprising an ink head for ejecting ink onto media and a spray head for spraying a liquid agent, A job list is created with the parameter whether there is a "yes" or "no" spray process in which the liquid agent is sprayed from the spray head, in addition to the printing process in which the ink is ejected from the ink head. In the aforementioned job list, multiple jobs containing common parameters are grouped together, and each job is executed for each group. The arrangement of the images targeted by the grouped jobs on the media is such that each group has a different arrangement area. An inkjet printer image forming method characterized in that the layout of the images within the image placement area is performed taking into consideration the size of the media and the sizes of the grouped plurality of images.

8. The image forming method for an inkjet printer according to claim 1, characterized in that the ink head and the spray head are scanned independently of the media.

Images