JP2010228240A - Apparatus for discharging liquid droplet, and method and program for detecting non-discharge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To accurately specify nozzles that are not in the state of discharging by eliminating the influence of expansion of recording material. <P>SOLUTION: The process of causing every N pieces of nozzles of a line head to discharge ink droplets to record a pattern 202 on a recording material moved in Y-direction is repeated as the nozzles caused to discharge ink droplets are changed, so that patterns 202 are recorded on the recording material by all the nozzles of the line head; thereafter, whether there should be discharge is switched in units of consecutive N pieces of nozzles, and all the nozzles that should discharge are caused to discharge ink droplets, whereby a line 206A of patterns is recorded on the recording material. After the patterns have been read, the range of pattern recording is cut out based on an X-direction end position of a rectangular pattern forming the line 206A of patterns, and nozzles that are not in the state of discharging are detected and specified according to the number of patterns 202 in the range cut out and to the positions of unrecorded patterns 202. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a droplet discharge device, a non-discharge detection method, and a program, and more particularly, a droplet discharge device provided with a plurality of nozzles each capable of discharging droplets so as to adhere to a recording material, and the droplet discharge device And a non-discharge detection program for applying the non-discharge detection method to the droplet discharge device.

  An ink jet recording system that records an image on a recording material by adhering ink droplets ejected from nozzles of a recording head to the recording material is now widely used as a recording system in an image recording apparatus. However, the ink jet recording method has a drawback that the image quality is remarkably deteriorated when an ejection abnormality such as non-ejection in which an ink droplet is not ejected from a nozzle occurs. In particular, in a system in which an image is recorded by a single conveyance of the recording material (single-pass image formation) by a full-line recording head in which nozzles are arranged over the entire width of the recording material, recording is performed when the above-described ejection abnormality occurs. A streak-like image defect along the conveyance direction occurs in the material, and the image quality of the recorded image is significantly reduced.

  For this reason, in an image recording apparatus that records an image by an ink jet method, various techniques for detecting the occurrence of ejection abnormality have been proposed. Specifically, for example, an in-line inspection device having a line CCD (Charged Coupled Device) having a structure in which photocells are arranged in a direction orthogonal to the scanning direction (conveying direction) of the recording material is provided, and a test pattern is formed on the recording material. A technique has been proposed in which the recorded test pattern is read by an in-line inspection apparatus and an ejection abnormality is detected from the test pattern reading result.

  Further, in Patent Document 1, a scanner unit that reads a printing result wider than the printing width is provided in an inkjet printer that performs printing by transporting a sheet with a print head fixed, and 1 on Noff (N = natural number) is provided on a part of the sheet or the sheet transport unit. ) Print the nozzle check pattern with vertical lines, shift the print nozzles when printing the test pattern for each page or within the same page, and count the number of read lines for the test pattern in the scanner section. If there is a non-ejecting nozzle, or if the part of the pattern to be printed is the same every time, the scanner unit reads and stores any part of the same part of the printed pattern, and for each pattern and page that has been read. Disclosed is a technology that determines the presence or absence of non-ejecting nozzles by comparing the number of lines read by the scanner at a specified position. To have.

JP 2004-9474 A

  By the way, when it is detected that a nozzle in a non-ejection state has occurred, it is ideal to perform a maintenance process that temporarily stops the image recording process and eliminates the non-ejection state from the viewpoint of suppressing deterioration in the image quality of the recorded image. However, especially in single pass image formation etc., the required level for processing speed (number of images that can be recorded per unit time) is high, and depending on the frequency of non-ejection, maintenance is performed each time a non-ejection nozzle is generated. Processing is undesirable because it leads to a significant decrease in processing speed. For this reason, when a non-ejecting nozzle occurs, for example, the non-ejecting nozzle is generated by increasing the amount of ink ejected from the nozzles located on both sides of the non-ejecting nozzle. Performing the correction process to make the image defects caused by the image inconspicuous, and then performing the maintenance process at a timing such as when the number of nozzles in the non-ejection state reaches a certain number, thereby reducing the frequency of execution of the maintenance process Can be considered.

  However, in order to perform the above processing, it is necessary to specify a nozzle that has become in a non-ejection state when the occurrence of non-ejection is detected. However, in recent image recording apparatuses having a recording head with a high resolution, a technique for identifying a nozzle in a non-ejection state has not been established. That is, for example, if the technique described in Patent Document 1 is applied, non-ejection occurs in any of the nozzles based on the lack of some of the test patterns recorded on the recording material. However, since recording materials such as recording paper partially expand and contract in millimeters according to the amount of ink adhering to each part, for example, from the end of the recording material to the position where the pattern was not recorded. Even if the distance is measured, the error included in the measured value is clearly larger than the nozzle pitch of the recording head. Therefore, based on the position where the pattern on the recording material was not recorded, It is difficult to accurately specify the nozzle).

  Instead of the position where the pattern on the recording material was not recorded, for example, the number of patterns was counted from the end of the recording material, and the number of patterns that were not recorded on the recording material was counted from the end of the recording material. It is also conceivable to determine the nozzles corresponding to the pattern that was not recorded (nozzles in the non-ejection state) on the basis of whether the pattern is a pattern. However, since the landing position of the ink droplets ejected from the nozzle on the recording material may be shifted due to the influence of mist or the like, also in this case, if the pattern does not exist at the intended position, the influence of the mist or the like By misdetecting the corresponding nozzle or its adjacent nozzle as non-ejection based on the pattern in which the recording position is deviated, or the pattern recording position by the nozzle adjacent to the non-ejection state nozzle is deviated due to the influence of mist, etc. There are cases where a nozzle in a non-ejection state cannot be accurately specified, for example, a nozzle in a non-ejection state is erroneously determined to be normal. In particular, with the recent increase in resolution of recording heads, it is becoming difficult to prepare a high-resolution sensor equivalent to the recording head as a reading sensor for reading a pattern from the viewpoint of cost and lengthening of reading time. However, when the reading sensor is set to a resolution lower than that of the recording head, it is expected that the frequency of occurrence of the erroneous detection and erroneous determination described above increases. Patent Document 1 does not disclose any configuration for solving the above problem.

  The present invention has been made in consideration of the above-described facts, and is a droplet ejection device, a non-ejection detection method, and a non-ejection method capable of accurately identifying a nozzle in a non-ejection state by eliminating the influence of expansion and contraction of a recording material. The purpose is to obtain a discharge detection program.

  In order to achieve the above object, according to a first aspect of the present invention, there is provided the liquid droplet ejection apparatus according to the first aspect, wherein a plurality of nozzles each capable of ejecting liquid droplets are attached to the recording material relatively moved in the first direction. A droplet discharge unit disposed at a different position along a second direction intersecting with one direction and a distribution range of positions of the nozzle of the droplet discharge unit along the second direction are divided into a plurality of sections. When the nozzles of the droplet discharge section are grouped into a plurality of groups corresponding to the divided individual sections based on the positions of the individual nozzles along the second direction, the nozzles belong to a specific group. For each of the plurality of groups, droplets are sequentially ejected from each nozzle, and the first pattern is recorded by the droplets ejected from each nozzle on the recording material relatively moved in the first direction. With The presence / absence of droplet ejection from the nozzles is switched in groups so that the groups adjacent to each other along the second direction are different, and each group belonging to a single group with droplet ejection is switched. Each droplet is ejected from a nozzle, and a partial pattern continuous along the second direction is recorded at a position within a predetermined distance along the first direction from the recording position of the first pattern on the recording material. This is performed for each group with droplet ejection, whereby recording control means for recording a second pattern consisting of a plurality of the partial patterns on the recording material, and recording on the recording material by the droplet ejection section. Based on the second pattern of the first pattern and the second pattern read as an image by the reading means, A recording range along the second direction on the image of the first pattern for each group is determined, and a nozzle in a non-ejection state is specified based on the first pattern existing in the determined recording range. And specifying means.

  According to the first aspect of the present invention, the plurality of nozzles each capable of ejecting droplets so as to adhere to the recording material relatively moved in the first direction are different from each other along the second direction intersecting the first direction. The liquid droplet ejection unit is disposed on the surface. Further, the recording control unit divides the distribution range of positions along the second direction of the nozzles of the droplet discharge unit into a plurality of sections, and the nozzles of the droplet discharge unit are aligned along the second direction of the individual nozzles. Based on the position, when divided into a plurality of groups corresponding to the divided individual sections, droplets are sequentially ejected from the nozzles belonging to the specific group, and each recording material is relatively moved in the first direction. Each of the plurality of groups records each of the first patterns with the droplets ejected from the nozzles. As a result, the recording material is tried to be ejected to all the nozzles of the droplet ejection section, and the droplets ejected from the nozzle are recorded on the recording material as the first pattern. On the basis of the number of the first patterns recorded in, it is possible to detect the presence / absence of a non-ejection nozzle. When recording the first pattern, the first patterns recorded by the droplets discharged from the nozzles of the same group are recorded at different positions along the first direction on the recording material. In addition, it is preferable to control the discharge timing of droplets from the nozzles.

  In addition, the recording control unit switches the presence / absence of liquid droplet ejection in groups so that the presence / absence of liquid droplet ejection from the nozzles is different between adjacent groups along the second direction. Droplets are respectively ejected from the nozzles belonging to, and a partial pattern continuous in the second direction is recorded at a position within a predetermined distance along the first direction from the recording position of the first pattern on the recording material. Is performed for each group with droplet ejection, thereby recording a second pattern composed of a plurality of partial patterns on the recording material. In addition, as said predetermined distance, the distance equivalent to the range which shows the same expansion-contraction degree on a recording material, or a distance smaller than the said distance can be applied, for example. Specifically, the range is preferably within 50 mm, more preferably within 20 mm.

  The recording position of the first pattern on the recording material by the droplets ejected from the individual nozzles of the droplet ejection section (for example, the distance from the end of the recording material to the recording position of the first pattern) According to the first aspect of the present invention, the partial pattern corresponding to each group with droplet ejection is changed to the first pattern on the recording material. Since the recording material is recorded at a position within a predetermined distance along the first direction from the recording position, the degree of expansion and contraction of the recording material at the recording position of the partial pattern (second pattern) is determined by the recording material at the recording position of the first pattern. The landing position on the recording material of the droplets ejected from each nozzle of each group with droplet ejection is substantially equal to the degree of expansion and contraction. And recording position of the pattern, the position are substantially equal in the second direction.

  Therefore, the partial pattern corresponding to the specific group with droplet discharge recorded on the recording material is discharged from each nozzle of the specific group at the position of both ends along the second direction at the recording position of the first pattern. It substantially coincides with the boundary position of the recording range along the second direction of the first pattern recorded on the recording material by the formed droplets. Further, since the presence / absence of liquid droplet ejection from the nozzles is switched in units of groups so that the groups adjacent to each other along the second direction are different, the individual groups with liquid droplet ejection, That is, partial patterns corresponding to every other group along the second direction are recorded on the recording material, and each partial pattern recorded on the recording material has both end portions along the second direction. Is the boundary of the recording range along the second direction of the first pattern recorded on the recording material by the droplets ejected from each nozzle of the group adjacent to the corresponding group at the recording position of the first pattern It will almost match the position.

  According to the first aspect of the present invention, the first pattern and the second pattern recorded on the recording material are read as an image by the reading unit that reads the image recorded on the recording material by the droplet discharge unit, and the specifying unit is the reading unit. The recording range along the second direction on the image of the first pattern for each group is determined and determined based on the second pattern of the first pattern and the second pattern read as an image by The nozzles in the non-ejection state are specified based on the first pattern existing in the recording range.

  Thus, in the first aspect of the invention, by using the second pattern, the recording of the first pattern along the second direction is not affected by the degree of expansion and contraction of the recording material at the recording position of the first pattern. Since the range can be accurately determined for each group, at least the specific first pattern not recorded on the recording material or the specific target nozzle corresponding to the specific first pattern recorded on the recording material, Which group the nozzle belongs to can be accurately determined, and the nozzles to be identified can be narrowed down. Then, the number of nozzles belonging to a single group can be set so that it can be specified which of the nozzles belonging to the single group determined by the specific target nozzle, or the recording material by each nozzle of the single group By differentiating the recording position of the first pattern in the first direction, it is possible to specify which of the nozzles belonging to the single group determined by the nozzle to be specified is determined. Therefore, according to the first aspect of the present invention, it is possible to accurately specify the nozzle in the non-ejection state while eliminating the influence of expansion and contraction of the recording material.

  In the first aspect of the present invention, as specified in the second aspect, for example, the specifying means includes the number of nozzles in which the number of first patterns existing in the recording range corresponding to the specific group belongs to the specific group. If the number of nozzles belonging to the specific group is smaller than the number of nozzles belonging to the specific group, it is determined that there is a non-ejection state nozzle. Among these recording positions, a nozzle in a non-ejection state can be specified based on a recording position where the first pattern does not exist on the image read by the reading unit.

  Further, in the invention described in claim 2, for example, as described in claim 3, the recording control means also includes a third pattern representing identification information for identifying each of the plurality of groups in combination with the second pattern. The identification information represented by a combination of the second pattern and the third pattern recorded at a position corresponding to the group, which is recorded on the recording material by the droplet discharge unit and determined that the nozzle in the non-discharge state exists. It is preferable to recognize the group to which the nozzles in the non-ejection state belong. Thus, when a group in which a nozzle in a non-ejection state exists is detected, for example, processing is performed such as counting the partial pattern (or the gap) corresponding to the group from the end of the recording material. In addition, the group can be recognized based on the identification information represented by the combination of the second pattern and the third pattern corresponding to the group, and the process for recognizing the group to which the nozzle in the non-ejection state belongs is simplified. .

  Further, the second pattern and the third pattern in the invention described in claim 3 specifically, for example, as described in claim 4, the second pattern represents identification information 2 depending on whether or not a partial pattern is recorded. Represents the value of the least significant bit of the decimal number, and the third pattern is composed of the same number of pattern strings as the number of bits higher than the least significant bit in the binary number representing the identification information, and each pattern string is an individual pattern string. Depending on whether or not the partial pattern to be configured is recorded, it is possible to represent values of different bits higher than the least significant bit of the binary number representing the identification information.

  Further, in the invention according to any one of claims 1 to 4, the recording control means corresponds to an individual group with droplet ejection in the second pattern as described in claim 5, for example. It is preferable that the partial pattern is recorded by ejecting liquid droplets from the same nozzle used for recording the first patterns of the individual groups.

  As described above, the landing position of the droplets ejected from the nozzle on the recording material may shift due to the influence of mist, etc., but this mist etc. continues for a certain period of time. When a nozzle with a deviation in landing position appears, if a droplet is ejected again from the nozzle, if the mist remains, the ejected droplet will land at approximately the same position as the previous time. . In the invention described in claim 5, since this is utilized and the second pattern is recorded by the same nozzle as the first pattern, the recording position of the first pattern is determined by the influence of mist or the like during the recording of the first pattern. If there is a nozzle shifted from the initial position, the liquid droplets ejected from the nozzle at the time of recording the second pattern also shift from the initial position as at the time of recording the first pattern.

  As a result, the positions of both ends along the second direction of the partial pattern corresponding to the specific group to which the nozzle belongs belong to the recording position of the first pattern due to the influence of mist or the like in each nozzle of the specific group. In the second direction of the first pattern recorded on the recording material by the droplets ejected from the nozzles of the specific group at the recording position of the first group, even if there is a nozzle displaced from the position of It almost coincides with the boundary position of the recording range along. Therefore, according to the fifth aspect of the present invention, the recording range along the second direction of the first pattern corresponding to each group can be accurately determined regardless of the presence or absence of the nozzle in which the landing position has shifted due to the influence of mist or the like. In the case where a nozzle in which the landing position has shifted due to the influence of mist or the like appears, the nozzle in the non-ejection state can be accurately identified.

  In the fifth aspect of the invention, it is difficult to make the color of the liquid droplets ejected from each nozzle during the recording of the first pattern different from the color of the liquid droplets ejected from each nozzle during the recording of the second pattern. Therefore, the second pattern is placed in a range adjacent to the recording range of the first pattern on the recording material in the second direction so that the distance between the recording position of the first pattern and the recording position of the second pattern is as small as possible. It is preferable to record.

  Further, in the invention according to any one of claims 1 to 4, when a plurality of droplet discharge portions that discharge droplets of different colors are provided, for example, as described in claim 6 The recording control means records the first pattern on the recording material by using the first droplet discharge portion among the plurality of droplet discharge portions, and the second droplet different from the first droplet discharge portion. You may comprise so that a 2nd pattern may be recorded on recording material using a discharge part. In this case, since the first pattern and the second pattern are recorded in different colors on the recording material, for example, as described in claim 7, the first pattern is within the recording range of the first pattern on the recording material. It is also possible to record the second pattern in an overlapping manner. Accordingly, since the first pattern and the second pattern can be recorded in a narrower range on the recording material, it is possible to suppress the consumption amount of the recording material accompanying the detection of the nozzles in the non-ejection state.

  Further, in the invention according to any one of claims 1 to 7, when the reading unit is configured to read the image recorded on the recording material divided into a plurality of pixels arranged at least along the second direction, For example, as described in claim 8, the recording control means has a recording interval of the first pattern along the second direction on the recording material such that the first reading range of the recording material by the single pixel of the reading means is the first. It is preferable to record the first pattern on the recording material so as to be larger than the size along the two directions. Accordingly, when the interval along the second direction of the plurality of pixels of the reading unit is larger than the arrangement interval along the second direction of each nozzle of the droplet discharge unit (resolution along the second direction in image reading by the reading unit) Is lower than the resolution along the second direction in the image recording by the droplet discharge portion), the single image obtained by the reading means reading the recording material on which the first pattern and the second pattern are recorded It is possible to prevent a state in which a plurality of first patterns are present in the pixel of the pixel, and to prevent a decrease in the accuracy of specifying a nozzle in a non-ejection state due to the occurrence of the state. Can do.

  Further, in the invention according to any one of claims 1 to 8, when the reading unit is configured to read the image recorded on the recording material divided into a plurality of pixels arranged at least along the second direction, For example, as described in claim 9, the recording control means has a first pattern size along the first direction on the recording material such that the first reading range on the recording material by a single pixel of the reading means is the first. The first pattern can be recorded on the recording material so as to be larger than the size along the direction.

  According to a tenth aspect of the present invention, there is provided a non-ejection detection method in which a plurality of nozzles each capable of ejecting droplets so as to adhere to a recording material relatively moved in the first direction intersects the first direction. A liquid droplet ejection unit disposed at different positions along the direction; a reading unit that reads an image recorded on the recording material by the liquid droplet ejection unit; and a computer. , Dividing the distribution range of the positions of the nozzles of the droplet discharge section along the second direction into a plurality of sections, and setting the nozzles of the droplet discharge sections along the second direction of the individual nozzles. On the recording material relatively moved in the first direction by sequentially discharging droplets from the nozzles belonging to the specific group when grouped into a plurality of groups corresponding to the divided individual sections based on the position To each The first pattern is recorded for each of the plurality of groups by the droplets ejected from the nozzle, and the presence / absence of droplet ejection from the nozzle is different between the adjacent groups along the second direction. As described above, the presence / absence of the droplet ejection is switched in units of groups, and each droplet is ejected from each nozzle belonging to a single group with droplet ejection, from the recording position of the first pattern on the recording material. The partial pattern continuous along the second direction is recorded at a position within a predetermined distance along the first direction for each group with droplet discharge, thereby comprising a plurality of the partial patterns. A second pattern is recorded on the recording material, and the second pattern of the first pattern and the second pattern read as an image by the reading means. And determining a recording range of the first pattern for each group along the second direction on the image based on the first pattern, and determining whether or not the first pattern exists within the determined recording range. Since the process of specifying the nozzles in the discharge state is performed, it is possible to accurately specify the nozzles in the non-discharge state by eliminating the influence of the expansion and contraction of the recording material, as in the first aspect of the invention.

  According to an eleventh aspect of the present invention, there is provided a non-ejection detection program in which a plurality of nozzles each capable of ejecting droplets so as to adhere to a recording material relatively moved in a first direction intersects the first direction. A computer for a liquid droplet ejection apparatus, comprising: a liquid droplet ejection section disposed at different positions along a direction; a reading unit that reads an image recorded on the recording material by the liquid droplet ejection section; and a computer. , Dividing the distribution range of the positions of the nozzles of the droplet discharge section along the second direction into a plurality of sections, and setting the nozzles of the droplet discharge sections along the second direction of the individual nozzles. A recording material that is relatively moved in the first direction by sequentially discharging droplets from each nozzle belonging to a specific group when grouped into a plurality of groups corresponding to the divided individual sections based on the position Recording each of the first patterns with droplets ejected from each nozzle is performed for each of the plurality of groups, and whether or not the droplets are ejected from the nozzles is adjacent to each other along the second direction. As described above, the presence / absence of droplet ejection is switched in units of groups, and droplets are ejected from nozzles belonging to a single group with droplet ejection, thereby recording the first pattern on the recording material. A plurality of the partial patterns are recorded by performing, for each group with droplet discharge, recording a partial pattern continuous along the second direction at a position within a predetermined distance from the position along the first direction. Recording control means for recording a second pattern comprising the recording material on the recording material, and the first pattern and the second pattern read as an image by the reading means Based on the second pattern of the turns, a recording range along the second direction on the image of the first pattern for each group is determined, and the second existing within the determined recording range. It is made to function as a specifying means for specifying a non-ejection state nozzle based on one pattern.

  A non-ejection detection program according to an eleventh aspect of the invention is a program for causing a computer of a droplet ejection apparatus configured to include the droplet ejection section and the reading unit to function as the recording control unit and the specifying unit. Therefore, when the computer executes the non-ejection detection program according to the invention according to claim 11, the non-ejection detection method according to claim 10 is performed by the droplet ejection device, As in the first and tenth aspects of the invention, it is possible to accurately specify a nozzle in a non-ejection state by eliminating the influence of expansion and contraction of the recording material.

  As described above, the present invention divides the distribution range of positions along the second direction (nozzle arrangement direction) of the nozzles of the droplet discharge section into a plurality of sections, When the nozzles are grouped into a plurality of groups corresponding to the divided individual sections based on the positions along the second direction of the nozzles, the droplets are sequentially ejected from the nozzles belonging to the specific group, and relative to the first direction. Each of the plurality of groups records the first pattern with the droplets ejected from the nozzles on the recording material to be moved, and the presence or absence of droplet ejection from the nozzles is adjacent in the second direction. The presence / absence of droplet discharge is switched in units of groups so that different groups match each other, and droplets are discharged from each nozzle belonging to a single group with droplet discharge to record the first pattern on the recording material. By recording each partial group with droplet discharge to record a continuous partial pattern along the second direction at a position within a predetermined distance along the first direction from the position, a second pattern consisting of a plurality of partial patterns is formed. Two patterns are recorded on the recording material and based on the second pattern of the first pattern and the second pattern read as an image by the reading unit, the second direction on the image of the first pattern for each group Since the nozzle in the non-ejection state is specified based on the first pattern existing in the judged recording range, the influence of the expansion / contraction of the recording material is eliminated and the non-ejection state is determined. It has an excellent effect that the nozzle can be accurately specified.

1 is a schematic configuration diagram of an image recording apparatus according to an embodiment. (A) is a perspective plan view of the recording head, (B) is an enlarged view of a part thereof, and (C) is a perspective plan view showing another example of the structure of the recording head. FIG. 4 is a cross-sectional view taken along line 4-4 of FIGS. 2A and 2B, showing a three-dimensional configuration of the ink chamber unit. FIG. 3 is an enlarged view showing a nozzle array of a recording head. It is a schematic block diagram of the ink supply system in an image recording device. It is a schematic block diagram which shows the structure of the electric system of an image recording device. It is an image figure which shows an example of a non-discharge detection pattern. It is a conceptual diagram for demonstrating an absolute pattern. It is a flowchart which shows the content of a non-ejection detection process. FIG. 6 is an image diagram for explaining extraction of a pattern recording region of a single group and identification of a nozzle in a non-ejection state in non-ejection detection processing. It is an image figure which shows the other example of a non-ejection detection pattern. It is an image figure which shows the other example of a non-ejection detection pattern.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an image recording apparatus 100 according to the present embodiment. The image recording apparatus 100 is capable of recording an image only on one side of the recording material 114, and includes a paper feeding unit 102 that supplies the recording material 114, a permeation suppression processing unit 104 that performs permeation suppression processing on the recording material 114, and a recording material. A processing liquid applying unit 106 for applying a processing liquid to 114, a recording unit 108 for applying color ink to the recording material 114 to form an image, and a fixing processing unit 110 for performing a fixing process on an image recorded on the recording material 114, In addition, a paper discharge unit 112 that conveys and discharges the recording material 114 on which an image is formed is provided. The image recording apparatus corresponds to the droplet discharge apparatus according to the present invention.

  The paper feed unit 102 is provided with a paper feed stand 120 on which the recording material 114 is stacked. A feeder board 122 is provided in front of the paper feed tray 120 (on the left side in FIG. 1), and the recording materials 114 loaded on the paper feed tray 120 are sent out one by one in order from the top by the feeder board 122. . The recording material 114 delivered by the feeder board 122 reaches the surface (circumferential surface) of the impression cylinder 126a of the permeation suppression processing unit 104 via the transfer cylinder 124a.

  The transfer drum 124a and the pressure drum 126a are provided with a gripper (not shown) for holding the leading end portion of the recording material 114. When the leading end portion of the recording material 114 held by the gripper of the transfer drum 124a reaches the contact position (transfer position of the recording material 114) between the transfer drum 124a and the pressure drum 126a, the gripper of the transfer drum 124a moves from the gripper of the pressure drum 126a. The leading end of the recording material 114 is transferred to the gripper. In this embodiment, one gripper 126 is provided with two grippers, and one transfer drum 124 is provided with one gripper.

  Further, the permeation suppression processing unit 104 includes a paper preheating unit 128 and a permeation suppression unit at positions facing the surface of the pressure drum 126a in order from the upstream side along the rotation direction of the pressure drum 126a (counterclockwise direction in FIG. 1). An agent head 130 and a permeation suppression agent drying unit 132 are provided. The paper preheating unit 128 and the permeation suppression agent drying unit 132 are provided with heaters that are controlled within a predetermined temperature range, and the recording material 114 held in the impression cylinder 126a is stored in the paper preheating unit 128 or the permeation suppression agent drying unit. When passing the position facing 132, the unit is heated by the heaters.

  The permeation inhibitor head 130 discharges the permeation inhibitor as droplets, thereby attaching the permeation inhibitor to the recording material 114 held by the impression cylinder 126a. Each of the recording heads 160C to 160C of the recording unit 108 described later. A head having the same configuration as 160B is applied. The penetration inhibitor is preferably a thermoplastic resin latex solution, but is not limited thereto. For example, tabular grains (mica etc.), water repellent (fluorine coating agent), etc. can be applied. is there. Further, instead of using an ink jet head to attach the penetration inhibitor to the recording material 114, various methods such as a spray method and a coating method can be applied.

  In addition, the treatment liquid application unit 106 disposed at the subsequent stage of the permeation suppression processing unit 104 includes a pressure drum 126b, and between the pressure drum 126a of the permeation suppression processing unit 104 and the pressure drum 126b of the treatment liquid application unit 106, A transfer drum 124b is provided so as to be in contact with each of them. Accordingly, the recording material 114 held on the pressure drum 126a of the permeation suppression processing unit 104 is transferred to the pressure drum 126b of the processing liquid application unit 106 via the transfer drum 124b after the permeation suppression processing is performed. .

  The processing liquid application unit 106 includes a sheet preheating unit 134 and a processing liquid head at positions facing the surface of the pressure drum 126b in order from the upstream side along the rotation direction of the pressure drum 126b (counterclockwise direction in FIG. 1). 136 and a processing liquid drying unit 138 are provided. The paper preheating unit 134, the treatment liquid head 136, and the treatment liquid drying unit 138 of the treatment liquid application unit 106 are respectively the same as the paper preheating unit 128, the penetration inhibitor head 130, and the penetration inhibitor drying unit 132 of the above-described penetration suppression processing unit 104. Since the configuration is the same, the description is omitted. Of course, a configuration different from that of the permeation suppression processing unit 104 can be applied.

  The processing liquid attached to the recording material 114 by the processing liquid applying unit 106 is contained in the ink ejected from the recording heads 160C to 160B arranged in the recording unit 108 at the subsequent stage toward the recording material 114. An acidic liquid having an action of aggregating the color material can be applied. Although the paper preheating unit 134 can be omitted, the recording material 114 is preheated by the heater of the paper preheating unit 134 before the treatment liquid is applied onto the recording material 114 as in this embodiment. In this case, the heating energy required for drying the treatment liquid can be kept low, and energy saving can be achieved.

Further, as the heating temperature of the heater of the processing liquid drying unit 138, the processing liquid applied to the surface of the recording material 114 by the discharge operation of the processing liquid head 136 disposed on the upstream side in the rotation direction of the pressure drum 126b is dried. The temperature is set such that a solid or semi-solid aggregation treatment agent layer (a thin film layer obtained by drying the treatment liquid) is formed on the recording material 114. The term “solid or semi-solid aggregation treatment agent layer” as used herein refers to the weight per unit area of water (g / m ² ) contained in the treated liquid after drying, and the unit of the treated liquid after drying. The moisture content obtained by dividing by the weight per area (g / m ² ) is in the range of 0 to 70%.

  In addition, the recording unit 108 disposed at the subsequent stage of the treatment liquid application unit 106 includes an impression cylinder 126c, and the pressure drum 126b of the treatment liquid application unit 106 and the impression cylinder 126c of the recording unit 108 are in contact with each other. A transfer cylinder 124c is provided. As a result, the recording material 114 held on the pressure drum 126b of the treatment liquid application unit 106 passes through the transfer cylinder 124c after the treatment liquid is applied to form a solid or semi-solid aggregation treatment agent layer. Is transferred to the impression cylinder 126c of the recording unit 108.

  The recording unit 108 corresponds to each of the seven colors of CMYKRGB at positions facing the surface of the impression cylinder 126c in order from the upstream side along the rotation direction of the impression cylinder 126c (counterclockwise direction in FIG. 1). Recording heads 160C, 160M, 160Y, 160K, 160R, 160G, and 160B, and solvent drying units 142a and 142b are provided. As each of the recording heads 160 </ b> C to 160 </ b> B, an ink jet recording head (ink jet head) is applied in the same manner as the permeation inhibitor head 130 and the treatment liquid head 136 described above. That is, each of the recording heads 160C to 160B ejects ink droplets of the corresponding color toward the recording material 114 held on the impression cylinder 126c.

  Each of the recording heads 160C to 160B has a length corresponding to the maximum width of the image forming area in the recording material 114 held by the pressure drum 126c, and the ink discharge surface has ink covering the entire width of the image forming area. This is a full-line head in which a plurality of discharge nozzles (shown with reference numeral 161 in FIG. 2) are arranged. Each of the recording heads 160C to 160B is fixedly installed so as to extend in a direction orthogonal to the rotation direction of the impression cylinder 126c (conveying direction of the recording material 114). Note that the present invention is not limited to the configuration in which an image is recorded using the seven colors of CMYKRGB as described above, and the color of the ink and the combination thereof can be changed as appropriate. (For example, light inks such as light cyan and light magenta), dark ink, and special color ink may be added. Further, the arrangement order of the heads of the respective colors is not limited to the order shown in FIG.

  As described above, in the configuration in which the full line head having the nozzle row covering the entire width of the image forming area of the recording material 114 is provided for each color of ink, recording is performed in the conveyance direction (sub-scanning direction) of the recording material 114. An image can be recorded in the image forming area of the recording material 114 only by performing the operation of relatively moving the material 114 and the recording heads 160 </ b> C to 160 </ b> B once (that is, by one sub-scan). As a result, an image can be recorded at a higher speed than when a serial (shuttle) type head that reciprocates in the direction (main scanning direction) perpendicular to the conveyance direction (sub-scanning direction) of the recording material 114 is used. Productivity can be improved. Note that each of the recording heads 160C to 160B corresponds to a droplet discharge unit according to the present invention.

  Further, the solvent drying units 142a and 142b are configured to include heaters controlled within a predetermined temperature range, similar to the paper preheating units 128 and 134, the permeation suppression agent drying unit 132, and the treatment liquid drying unit 138 described above. . As will be described later, when ink droplets adhere to the solid or semi-solid aggregation processing agent layer formed on the recording material 114, an ink aggregate (coloring material aggregate) is formed on the recording material 114. At the same time, the ink solvent separated from the color material spreads to form a liquid layer in which the aggregating agent is dissolved. Thus, the solvent component (liquid component) remaining on the recording material 114 causes not only curling of the recording material 114 but also image degradation. Therefore, in the present embodiment, after the ink droplets of the respective colors are attached to the recording material 114 from the recording heads 160C to 160B, a drying process for evaporating the solvent component by applying heat by the heaters of the solvent drying units 142a and 142b is performed. Is going.

  In addition, the fixing processing unit 110 disposed at the subsequent stage of the recording unit 108 includes a pressure drum 126d, and the pressure drum 126c of the recording unit 108 and the pressure drum 126d of the fixing processing unit 110 are in contact with each other. A transfer drum 124d is provided. Accordingly, the recording material 114 held on the pressure drum 126c of the recording unit 108 is delivered to the pressure drum 126c of the recording unit 108 via the transfer drum 124d after ink droplets of each color are attached by the recording unit 108. It is. The fixing processing unit 110 includes an in-line sensor 144 and heating rollers 148a and 148b at positions facing the surface of the pressure drum 126d in order from the upstream side along the rotation direction (counterclockwise direction in FIG. 1) of the pressure drum 126d. Each is provided.

  The in-line sensor 144 includes a line sensor in which a plurality of photoelectric conversion cells (pixels) are arranged in a line along the width direction of the recording material 114 (instead of this, an area sensor may be used) and a single reading. The line sensor is configured to include a reduction lens arranged to be able to read the range over the entire width of the recording material 114, and an image recorded on the recording material 114 can be read by each of the recording heads 160C to 160B. Yes. Note that the reading resolution of the in-line sensor 144 is set sufficiently lower than the recording resolution of each of the recording heads 160C to 160B of the recording unit 108 for the purpose of reducing cost and shortening the reading time of the reading result from the line sensor. Yes.

  As will be described later, when non-ejection detection processing for detecting the non-ejection state nozzles of the recording heads 160C to 160B is performed, an image non-recording area on the recording material 114 (for example, the leading end of the recording material 114) is formed. A non-ejection detection pattern (see FIG. 7) is recorded, and the non-ejection detection pattern on the recording material 114 is read by the in-line sensor 144. And the process which detects the nozzle of a non-ejection state based on the pattern reading image obtained when the in-line sensor 144 reads the non-ejection detection pattern on the recording material 114 is performed. The inline sensor 144 corresponds to the reading unit according to the present invention.

  In the fixing processing unit 110, after image recording, fixing processing is performed by heating and pressing with the heating rollers 148a and 148b. However, the fixing processing unit 110 is not limited to this, and for example, UV light is applied after attaching transparent UV ink. Other configurations such as fixing the image on the recording material 114 by curing the transparent UV ink by irradiation may be applied.

  In addition, a paper discharge unit 112 disposed at a stage subsequent to the fixing processing unit 110 includes a paper discharge drum 150 that receives the recording material 114 that has been subjected to the fixing process, a paper discharge tray 152 on which the recording material 114 is stacked, and a paper discharge unit 152. A paper discharge chain 154 provided between a sprocket provided on the paper cylinder 150 and a sprocket provided above the paper discharge table 152 and provided with a plurality of paper discharge grippers is provided.

  Next, the recording heads 160C to 160B will be described. As shown in FIGS. 2A and 2B, the recording head 160 according to the present embodiment includes a plurality of inks including nozzles 161 serving as ink droplet ejection holes, pressure chambers 162 corresponding to the nozzles 161, and the like. The chamber units 163 are arranged in a matrix (two-dimensionally) so that the chamber units 163 are substantially along the head longitudinal direction (main scanning direction perpendicular to the recording medium conveyance direction: the second direction in the present invention). Thus, a high density of nozzle intervals (projection nozzle pitch), and a high density of dot pitches formed on the recording material 114 are realized. The recording head 160 is not limited to the configuration shown in FIG. 2A. For example, as shown in FIG. 2C, a short head block 160 ′ in which a plurality of nozzles 161 are two-dimensionally arranged is provided. A configuration in which they are arranged in a zigzag pattern and connected together may be used, or a configuration in which short heads are arranged in a row may be used although illustration is omitted.

  The pressure chamber 162 has a substantially square planar shape, and nozzles 161 and supply ports 164 are provided at both corners on a diagonal line. As shown in FIG. 3, each pressure chamber 162 communicates with a common flow path 165 through a supply port 164. The common channel 165 communicates with an ink supply tank (not shown) that is an ink supply source, and the ink supplied from the ink supply tank is distributed and supplied to each pressure chamber 162 via the common channel 165. A piezoelectric element 168 having an individual electrode 167 is joined to a diaphragm 166 that constitutes the top surface of the pressure chamber 162 and also has a function as a common electrode, and the piezoelectric element 168 has a drive voltage applied to the individual electrode 167. Is deformed, and an ink droplet is ejected from the nozzle 161 as the piezoelectric element 168 is deformed. As the ink droplets are ejected from the nozzle 161, new ink is supplied from the common channel 165 through the supply port 164 to the pressure chamber 162.

  In the present embodiment, the piezoelectric element 168 is used as the ejection force generating means for ejecting ink droplets from the nozzle 161. However, instead of this, a heater is provided in the pressure chamber 162, and the pressure of film boiling due to the heating of the heater is provided. It is also possible to apply a thermal method in which ink is ejected using the above.

  As shown in FIG. 4, the recording head 160 according to the present embodiment has an inclination in which the ink chamber unit 163 having the above-described configuration forms a constant angle θ that is not orthogonal to the row direction along the main scanning direction and the main scanning direction. A large number of nozzles are arranged in a matrix with a fixed arrangement pattern along the column direction, thereby realizing a high density of the projection nozzle pitch. That is, since a plurality of ink chamber units 163 are arranged at a constant pitch d along a direction that forms a constant angle θ with respect to the main scanning direction, the projection nozzle pitch P along the main scanning direction is d × cos θ. In the main scanning direction, each nozzle 161 can be handled equivalently as a linear arrangement with a constant pitch P. As a result, it is possible to obtain a print head equivalent to a nozzle array with a high density of 2400 nozzles per inch (2400 nozzles / inch) along the main scanning direction.

  A full line head having a nozzle row having a length corresponding to the entire recordable width causes ink droplets to be ejected from the nozzles in the width direction of the recording material 114 (direction perpendicular to the conveyance direction of the recording material 114). Nozzle drive method for recording one line along the line (a line consisting of one line of dots or a line consisting of multiple lines of dots) is: (1) drive all nozzles simultaneously, (2) move nozzles from one to the other (3) The nozzle is divided into a plurality of blocks, and each block is sequentially driven from one to the other. However, in this specification, any one of the above driving The driving of the nozzles for recording one line along the width direction of the recording material 114 according to the method is defined as main scanning.

  When driving the nozzles 161 arranged in a matrix as shown in FIGS. 2A and 2B, the main scanning (nozzle driving method) of the above (3) is preferable. Specifically, the nozzles 161-11, 161-12, 16-13, 161-14, 161-15, 161-16 shown in FIG. 4 are made into one block (other nozzles 161-21,. -26 as one block, nozzles 161-31,..., 161-36 as one block,...), And nozzles 161-11, 161-12,. By sequentially driving, one line can be recorded in the width direction of the recording material 114.

  On the other hand, in this specification, the above-described full line head and the recording material 114 are moved relative to each other to thereby form one line formed by the above-described main scanning (a line composed of a single row of dots or a line composed of a plurality of rows of dots). Repeating this recording is defined as sub-scanning. The direction indicated by one line (or the longitudinal direction of the belt-like region) recorded by the main scanning is referred to as a main scanning direction, and the direction in which the sub scanning is performed is referred to as a sub scanning direction. In other words, in the present embodiment, the conveyance direction of the recording material 114 is the sub-scanning direction, and the width direction of the recording material 114 orthogonal thereto is the main scanning direction.

  In the implementation of the present invention, the nozzle arrangement structure is not limited to the illustrated example. For example, various nozzle arrangement structures such as an arrangement structure having one nozzle row in the sub-scanning direction can be applied. Further, the present invention is not limited to the recording method using a line type head, and a short head that is less than the length in the width direction of the recording material 114 is scanned in the width direction of the recording material 114 to perform recording in the width direction. When the recording in the width direction is completed once, the recording material 114 is moved by a predetermined amount in the direction orthogonal to the width direction, recording in the width direction of the recording material 114 in the next recording area is performed, and this operation is repeated. It is also possible to apply to a serial system in which recording is performed over the entire recording area of the recording material 114.

  Next, the configuration of the ink supply system of the image recording apparatus 100 will be described. As shown in FIG. 5, the ink supply system is provided with an ink supply tank 170 that is a base tank that supplies ink to the recording head 160. The ink supply tank 170 includes a system that replenishes ink from a replenishment port (not shown) and a cartridge system that replaces the entire tank when the remaining amount of ink is low. A cartridge system is suitable for changing the ink type according to the intended use. In this case, it is preferable that the ink type information is identified by a barcode or the like, and ejection control is performed according to the ink type.

  A filter 172 for removing foreign substances and bubbles is provided between the ink supply tank 170 and the recording head 160. The mesh size of the filter 172 is preferably equal to or smaller than the nozzle diameter (for example, about 20 μm). Although illustration is omitted, a sub tank may be provided in the vicinity of the recording head 160 or integrally with the recording head 160. The sub tank has a function of improving refill as well as exhibiting a damper effect that prevents fluctuations in the internal pressure of the recording head.

  Further, the image recording apparatus 100 is provided with a cap 174 for preventing the nozzle 161 from drying or preventing an increase in ink viscosity near the nozzle, and a cleaning blade 176 as a means for cleaning the ink ejection surface of the recording head 160. The recording head 160 can be moved relative to the maintenance unit including the cap 174 and the cleaning blade 176 by a moving mechanism (not shown). Moved to position. The cap 174 is displaced up and down relatively with respect to the recording head 160 by an elevator mechanism (not shown). The nozzle surface of the recording head 160 is covered with the cap 174 when the cap 174 is raised to a predetermined lifted position when the power is turned off or during printing standby.

  In addition, when the frequency of use of the specific nozzle 161 during image recording or standby is low and ink droplets are not ejected from the specific nozzle 161 for a certain period of time, the solvent in the ink staying in the vicinity of the nozzle evaporates. As a result, the ink viscosity increases, and even if the piezoelectric element 168 is operated, there is a possibility that an ink droplet is not ejected from the nozzle 161 and a non-ejection state occurs. For this reason, in this embodiment, the piezoelectric element 168 is operated before the ink discharge state (before the ink viscosity deviates from the range in which the ink droplet is discharged by the operation of the piezoelectric element 168), and the deteriorated ink ( Preliminary discharge (also referred to as purge, idle discharge, or dummy discharge) is performed toward the cap 174 (ink receiver) in order to discharge the ink having increased viscosity staying in the vicinity of the nozzle.

  Further, even when bubbles are mixed into the ink in the recording head 160 (in the pressure chamber 162), the ink droplets are not ejected from the nozzles even when the piezoelectric element 168 is operated. In this embodiment, in such a case, the nozzle surface of the recording head 160 is covered with the cap 174, and the suction pump 177 is operated to remove ink (ink mixed with bubbles) in the pressure chamber 162 by suction. A suction operation for feeding the removed ink to the collection tank 178 is performed. This suction operation (sucking out deteriorated ink whose viscosity has been increased (solidified)) is also performed when an initial ink is loaded into the head or at the start of use after a long stop. The suction operation is performed on the entire ink in the pressure chamber 162, and the amount of ink consumption is large. Therefore, it is preferable to perform preliminary ejection when the increase in the viscosity of the ink is small.

  The cleaning blade 176 is made of an elastic member such as rubber, and can slide on the ink discharge surface of the recording head 160 by a blade moving mechanism (not shown). When ink droplets or foreign matter adhere to the ink ejection surface, the ink ejection surface is wiped by sliding the cleaning blade 176 on the ink ejection surface, and the ink ejection surface is cleaned.

  As shown in FIG. 6, the image recording apparatus 100 includes a system control unit 182. The system control unit 182 includes a communication interface (I / F) unit 180, an image memory 184, a motor driver 186, a heater driver 188, and a print. Control units 190 are connected to each other. Note that the print control unit 190 and the system control unit 182 can be integrated to form a single processor.

  The communication I / F unit 180 is an interface unit that receives image data sent from the host computer 196. As a communication protocol in the communication I / F unit 180, any of a serial interface such as USB (Universal Serial Bus), IEEE 1394, Ethernet (registered trademark), a wireless network, or a parallel interface such as Centronics can be applied. Image data sent from the host computer 196 is taken into the image recording apparatus 100 via the communication I / F unit 180 and temporarily stored in the image memory 184.

  The image memory 184 is a storage unit that temporarily stores an image input via the communication I / F unit 180, and data is read and written through the system control unit 182. The image memory 184 may be non-rewritable storage means, or may be rewritable storage means such as an EEPROM. Further, the image memory 184 is not limited to a memory made of a semiconductor element, and a magnetic storage medium such as a hard disk may be used. The image memory 184 is used as a temporary storage area for image data, and is also used as a program development area and a calculation work area for the CPU. The image memory 184 may store various data necessary for processing executed by the CPU of the system control unit 182. Further, the non-ejection detection pattern data described later is stored in the image memory 184 in advance.

  The system control unit 182 includes a CPU and its peripheral circuits, and functions as a control device that controls the entire image recording apparatus 100 according to a predetermined program, and also functions as an arithmetic device that performs various calculations. That is, the system control unit 182 controls the communication I / F unit 180, the image memory 184, the motor driver 186, the heater driver 188, etc., and performs communication control with the host computer 196, read / write control of the image memory 184, and the like. At the same time, a control signal for controlling the motor 198 and the heater 199 of the transport system is generated.

  The system control unit 182 includes a program storage unit 182A. Various control programs are stored in the program storage unit 182A, and the control programs are read out and executed by the CPU in accordance with instructions from the system control unit 182. The program storage unit may use a semiconductor memory such as a ROM or an EEPROM, or may use a magnetic disk or the like. An external interface may be provided and a memory card or PC card may be used. Of course, you may provide several recording media among these recording media. Note that the program storage unit may also be used as a storage means such as operation parameters. The program storage unit 182A also stores a non-ejection detection program for performing non-ejection detection processing described later by the CPU of the system control unit 182.

  A motor 198 is connected to the motor driver 186, and the motor driver 186 drives the motor 198 in accordance with an instruction from the system control unit 182. The motor 198 shown in FIG. 6 is actually composed of a plurality of motors, and includes, for example, the pressure drums 126a to 126d, the transfer drums 124a to 124d and the motor for driving the paper discharge drum 150 shown in FIG. . A heater 199 is connected to the heater driver 188, and the heater driver 188 drives the heater 199 in accordance with an instruction from the system control unit 182. The heater 199 shown in FIG. 6 actually includes a plurality of heaters. For example, the paper preheating units 128 and 134, the permeation suppressor drying unit 132, the treatment liquid drying unit 138, the solvent drying unit 142a, and the like shown in FIG. A heater 142b, a heater built in the heating rollers 148a and 148b, and the like are included.

  In addition, an inline sensor 144 is also connected to the system control unit 182, and the data of the pattern read image obtained by reading the non-ejection detection pattern recorded on the recording material 114 by the inline sensor 144 is the inline sensor 144. To the system control unit 182.

  A head driver 194, a treatment liquid head driver 195, a permeation suppression agent head driver 197, and an image buffer memory 192 are connected to the print control unit 190. In accordance with an instruction from the system control unit 182, the print control unit 190 generates image recording data, a signal for discharging a permeation inhibitor, and a signal for discharging a processing liquid from the image data stored in the image memory 184. The image recording data (dot data) generated is supplied to the head driver 194, and the generated permeation inhibitor discharge signal is transmitted to the permeation inhibitor head driver. The processing liquid discharge signal generated and supplied to 197 is supplied to the processing liquid head driver 195. In addition, when the above-described signal processing is performed by the print control unit 190, image data, parameters, and other data are temporarily stored in the image buffer memory 192.

  A recording head 160 is connected to the head driver 194, and the head driver 194 applies a drive signal to be applied to the piezoelectric element 168 of the recording head 160 based on image recording data supplied from the print control unit 190. A driving circuit that generates and drives the piezoelectric element 168 by applying the driving signal to the piezoelectric element 168 is included. Further, when the ink droplets are ejected from the recording head 160 by driving the piezoelectric element 168, the head driver 194 also controls the ejection droplet amount and ejection timing of the recording head 160. Thereby, dots of a desired size are recorded on the recording material 114 in a desired arrangement. The head driver 194 may include a feedback control system for keeping the driving condition of the recording head 160 constant.

  Further, a permeation inhibitor head driver 197 is connected to a permeation inhibitor head driver 197, and the permeation inhibitor head driver 197 follows the permeation inhibitor discharge signal supplied from the print control unit 190. The permeation inhibitor is discharged from Further, the processing liquid head 136 is connected to the processing liquid head driver 195, and the processing liquid head driver 195 discharges the processing liquid from the processing liquid head 136 in accordance with the processing liquid discharge signal supplied from the print control unit 190. Let

  Next, as the operation of the present embodiment, the operation of each part of the image recording apparatus 100 when an image is recorded on the recording material 114 will be described first. When an image is recorded on the recording material 114, the recording material 114 is sent out from the paper feeding table 120 of the paper feeding unit 102 to the feeder board 122. The recording material 114 is held by the pressure drum 126a of the permeation suppression processing unit 104 via the transfer cylinder 124a, preheated by the paper preheating unit 128, and the permeation suppression agent discharged from the permeation suppression agent head 130 is attached. . Thereafter, the recording material 114 held on the impression cylinder 126a is heated by the permeation suppression agent drying unit 132, and dried by evaporation of the solvent component (liquid component) of the permeation suppression agent.

  The recording material 114 subjected to the permeation suppression processing is transferred from the pressure drum 126a of the permeation suppression processing unit 104 to the pressure drum 126b of the processing liquid application unit 106 via the transfer drum 124b. The recording material 114 held on the pressure drum 126b is preheated by the paper preheating unit 134, and the processing liquid discharged from the processing liquid head 136 is attached thereto. Thereafter, the recording material 114 held on the pressure drum 126b is heated by the processing liquid drying unit 138, and is dried by evaporating the solvent component (liquid component) of the processing liquid. As a result, a solid or semi-solid aggregation treatment agent layer is formed on the recording material 114.

  The recording material 114 on which the treatment liquid is adhered to form a solid or semi-solid aggregation treatment agent layer is transferred from the impression cylinder 126b of the treatment liquid application section 106 to the impression cylinder of the recording section 108 via the transfer cylinder 124c. It is passed to 126c. When the leading end of the recording material 114 held on the pressure drum 126b reaches the position where the recording heads 160C to 160B are disposed, the non-ejection detection pattern is recorded on the leading end of the recording material 114 by the recording heads 160C to 160B. When the leading end of the recording material 114 on which the non-ejection detection pattern is recorded reaches the position where the in-line sensor 144 of the fixing processing unit 110 is disposed, the non-ejection detection pattern is read by the in-line sensor 144 and obtained by the reading. Based on the image data, a non-ejection nozzle is detected, and a non-ejection detection process for applying the ejection correction mode and recovering the non-ejection state is performed as necessary. This non-ejection detection process will be described later. . After the non-ejection detection process is performed, ink droplets of different colors are ejected from the recording heads 160C to 160B in accordance with the input image data, and the ink droplets ejected from the recording heads 160C to 160B Attached to the image recording area on the recording material 114 held by 126b.

  Here, when the ink droplet lands on the aggregation treatment agent layer formed on the recording material 114, the contact surface between the ink droplet and the aggregation treatment agent layer has a predetermined area due to the balance between the flying energy of the ink droplet and the surface energy. become. The aggregation reaction starts immediately after the ink droplets land on the aggregation treatment agent. This aggregation reaction starts only from the contact surface between the ink droplet and the aggregation treatment agent layer and occurs only in the vicinity of the contact surface. Since the color material in the ink is aggregated in a state where the adhesive force is obtained with the contact area, the color material movement is suppressed. Even if other ink droplets land adjacent to this ink droplet, the color material of the ink that has landed first is already agglomerated, so the color material does not mix with the ink that lands later, and bleeding does not occur. Deterred. Note that after the color material is aggregated, the separated ink solvent spreads, and a liquid layer in which the aggregation treatment agent is dissolved is formed on the recording material 114. The recording material 114 held on the impression cylinder 126c is heated by the solvent drying units 142a and 142b, and the solvent component (liquid component) separated from the ink aggregates on the recording material 114 is evaporated to be dried. As a result, curling of the recording material 114 is prevented and image quality deterioration due to the solvent component is suppressed.

  The recording material 114 on which the color ink is applied by the recording unit 108 and the image is recorded is transferred from the impression cylinder 126c of the recording unit 108 to the impression cylinder 126d of the fixing processing unit 110 via the transfer cylinder 124d. As described above, the non-ejection detection pattern is read by the in-line sensor 144 and the recording material 114 held on the pressure drum 126d is heated and pressed by the heating rollers 148a and 148b. Further, thereafter, the recording material 114 is transferred from the pressure drum 126 d to the paper discharge drum 150 and conveyed to the paper discharge tray 152 by the paper discharge chain 154. The recording material 114 on which an image has been recorded in this manner is conveyed above the paper discharge tray 152 by the paper discharge chain 154 and is stacked on the paper discharge tray 152.

  Next, prior to the description of the non-ejection detection process according to the present embodiment, a non-ejection detection pattern recorded on the leading end portion of the recording material 114 by the non-ejection detection process will be described. As shown in FIG. 7, the non-ejection detection pattern 200 according to the present embodiment includes an incremental pattern group 204 including a large number of incremental patterns 202 and an absolute pattern 206. In FIG. 7, the arrow X direction represents the main scanning direction, and the arrow Y direction represents the sub-scanning direction (conveying direction of the recording material 114).

  Each incremental pattern 202 is a linear pattern extending in the Y direction (sub-scanning direction) in FIG. 7, and the recording of the single incremental pattern 202 on the recording material 114 is performed in the sub-scanning direction. In this state, the ejection of ink droplets from a single nozzle is repeated for a certain time (a certain number of times). The incremental pattern 202 (incremental pattern group 204) is a pattern for detecting a non-ejection state nozzle (non-ejection nozzle). The incremental pattern group 204 ejects ink droplets from the nozzle as described above. It is formed by recording a single incremental pattern 202 on the recording material 114 for each of all the nozzles of the recording head 160.

  Here, in the present embodiment, when the non-ejection detection pattern 200 is generated, all the nozzles of each recording head 160 are N nozzles from one end in the nozzle row along the main scanning direction (projection nozzle row along the main scanning direction). The nozzles are grouped by grouping them. As a result, a large number of nozzle groups each consisting of N nozzles of N · i + 1 to N · i + Nth (where i = 0, 1, 2,...) Are formed. In this embodiment, ink droplets are ejected from the same single nozzle in each group to record the incremental pattern 202 on the recording material 114, and ink droplets are ejected in each group. In this way, the incremental pattern group 204 is formed by repeating the process until the incremental pattern 202 is recorded on the recording material 114 by all the nozzles in each group while switching the nozzles that record the incremental pattern 202. In this way, the incremental pattern group 204 is set.

  For example, in the incremental pattern group 204 shown in FIG. 7, first, ink droplets are ejected from the first nozzle in each group to record the first-row incremental pattern 202 on the recording material 114, and then each individual pattern is recorded. Ink groups are ejected from the (N / 2 + 1) th nozzle in each group to record the second-row incremental pattern 202 on the recording material 114, and then the second, N / 2 + 2, second, third, N / It is formed by switching the nozzles for recording the incremental pattern 202 by ejecting ink droplets in the order of 2 + 3.

  In the incremental pattern group 204 shown in FIG. 7, the arrangement pitch PTX (see also FIG. 7) of the incremental pattern 202 along the arrow X direction (main scanning direction) in FIG. 7 is PTX = P · N (provided that P is the projection nozzle pitch along the main scanning direction). In this embodiment, when the reading pitch (pixel pitch) along the X direction (main scanning direction) of the inline sensor 144 is PSX, the arrangement pitch PTX of the incremental pattern 202 satisfies the condition of PTX ≧ PSX. The number N of nozzles forming a single group is set. Further, in this embodiment, when the length along the Y direction (sub-scanning direction) of the reading area for one pixel of the inline sensor 144 on the recording material 114 is LSY, the incremental pattern 202 has a Y direction (sub-scan). The ejection time (number of ejections) of the ink droplets from the nozzles in the recording of the single incremental pattern 202 is set so that the length LTY (see also FIG. 7) along the scanning direction) satisfies the condition of LTY ≧ LSY. Has been.

  By configuring the incremental pattern 202 (incremental pattern group 204) so as to satisfy the above conditions, each pixel of the inline sensor 144 on the recording material 114 is read when the inline sensor 144 reads the incremental pattern group 204. Since there is only one incremental pattern 202 or no incremental pattern 202 in the corresponding reading area, the reading resolution is sufficiently lower than the recording resolution of the recording head 160. Using the in-line sensor 144, it is possible to detect a non-ejection state in units of nozzles. The above matter corresponds to the inventions described in claims 8 and 9. In the example of FIG. 7, the number N of nozzles forming a single group is set to 10, but the number N of nozzles forming a single group can be appropriately changed to satisfy the above-described condition. Needless to say. The above-mentioned incremental pattern 202 (incremental pattern group 204) corresponds to the first pattern according to the present invention.

On the other hand, the absolute pattern 206 shown in FIG. 7 is configured such that seven pattern rows 206A to 206G arranged in the X direction (main scanning direction) are arranged adjacent to each other in the Y direction (sub scanning direction). ing. A group ID for identifying each group (this group ID corresponds to the identification information described in claim 3) is assigned to each of the nozzle groups composed of the N nozzles. The group ID is represented by a 7-bit binary number. Seven pattern row 206A~206G corresponds to each bit of the group identification information, as shown in FIG. 8, the least significant bit (2 ⁰ bit) of the pattern sequence 206A is group identification information, pattern sequence 206B is the second least significant bit of the group identification information (2 ¹ bit), pattern string 206C is the third least significant bit of the group identification information (2 ² bit), and pattern string 206D is the group identification. They are respectively correspond from the lower information in the fourth position of the bits (2 ^3-bit). Although not shown, the pattern string 206E is the fifth digit bit from the lower order of the group identification information, the pattern string 206F is the sixth digit bit from the lower order of the group identification information, and the pattern string 206G is the group identification information. Each corresponds to the most significant bit.

  Recording of each of the pattern rows 206A to 206G of the absolute pattern 206 on the recording material 114 is formed by switching ejection / non-ejection of ink droplets in units of individual groups of nozzles. For example, in the absolute pattern 206 shown in FIG. 7, first, ejection of ink droplets from all the nozzles of the odd-numbered group is repeated for a certain time (a certain number of times) to record the pattern row 206A on the recording material 114, and then 2i + 1. The pattern row 206B is recorded on the recording material 114 by repeating ejection of ink droplets from all nozzles of the 2nd and 2i + 1th (where i = 0, 1, 2,...) Groups for a certain time (a certain number of times). In this case, the pattern row 206C is recorded on the recording material 114 by repeating ejection of ink droplets from all the nozzles of the 4i + 1st to 2i + 4th (where i = 0, 1, 2,...) Groups for a certain time (a certain number of times). Subsequently, a pattern is formed on the recording material 114 by repeating ejection of ink droplets from all nozzles of the 8i + 1st to 8i + 8th (where i = 0, 1, 2,...) Groups for a certain time (a certain number of times). 206D is recorded, and then the ejection of ink droplets from all nozzles of the 16i + 1st to 16i + 16th (where i = 0, 1, 2,...) Groups is repeated for a certain time (a certain number of times) on the recording material 114. The recording material 114 is printed by recording the pattern row 206E and then repeating ejection of ink droplets from all nozzles of the 32i + 1st to 32i + 32th (where i = 0, 1, 2,...) Groups for a certain time (a certain number of times). The pattern row 206F is recorded on the top, and then the recording is performed by repeating ejection of ink droplets from all nozzles of the 64i + 1st to 64i + 44th (where i = 0, 1, 2,...) Groups for a certain time (a certain number of times). It is formed by recording the pattern row 206G on the material 114.

  The recording position of the absolute pattern 206 on the recording material 114 can be a distance along the sub-scanning direction with respect to the recording position of the incremental pattern 202 (incremental pattern group 204) on the recording material 114. It is preferable that the recording position is as small as possible, and if possible, it is more preferable that the recording positions of both patterns are made coincident by recording both patterns in an overlapping manner. However, in the non-ejection detection pattern 200 shown in FIG. 7, the incremental pattern 202 (incremental pattern group 204) and the absolute pattern 206 are formed of the same color ink, and the incremental pattern 202 and the absolute pattern 206 are overlapped. Since both patterns cannot be distinguished after recording, in the non-ejection detection pattern 200 shown in FIG. 7, the absolute pattern 206 is arranged at a position adjacent to the incremental pattern 202 (incremental pattern group 204) in the sub-scanning direction. ing. Of the absolute pattern 206 described above, the pattern row 206A corresponds to the second pattern according to the present invention, and the pattern rows 206B to 206G correspond to the third pattern according to claim 3, respectively.

  Next, non-ejection detection processing performed by the system control unit 182 using the above-described non-ejection detection pattern will be described with reference to FIG. This non-ejection detection process is realized by the non-ejection detection program stored in the program storage unit 182A being executed by the CPU of the system control unit 182, and a new recording material 114 held in the impression cylinder 126b. Is performed each time the leading end of the recording head reaches the position where the recording heads 160C to 160B are disposed. In the present embodiment, the system control unit 182 corresponds to the computer according to claims 10 and 11.

  In the non-ejection detection process, first, in step 300, data of the above-described non-ejection detection pattern (see FIG. 7) is read from the image memory 184. In the next step 302, after generating the non-ejection detection pattern recording data for recording the non-ejection detection pattern on the recording material 114 by the recording head 160 from the data read in step 300, the generated recording data is By supplying the head driver 194 and driving the recording heads 160C to 160B in order by the head driver 194 based on the supplied recording data, the non-ejection detection patterns of the respective colors are arranged at the leading end of the recording material 114 so as not to overlap each other. To record each. The steps 300 and 302 correspond to the recording control means according to the present invention (more specifically, the recording control means according to claims 3 and 5).

  In step 304, a non-ejection detection pattern of each color recorded on the leading end portion of the recording material 114 is read by the inline sensor 144, and a pattern read image obtained by the inline sensor 144 reading the non-ejection detection pattern of each color. Are acquired from the in-line sensor 144. In step 306, the recording head 160 to be detected as a non-ejection nozzle is selected from the recording heads 160 </ b> C to 160 </ b> B by the following processing, and is selected as a detection target from the pattern read image represented by the data acquired in step 304. The area of the non-ejection detection pattern recorded by the recording head 160 is extracted.

  The processing after the next step 308 corresponds to the specifying means according to the present invention (specifically, the specifying means described in claims 2 and 3). First, in step 308, it exists in the region extracted in step 306. Among the absolute patterns 206, the pattern (incremental) of each nozzle of a single unprocessed nozzle among the nozzles of the recording head 160 to be detected based on the pattern row 206A corresponding to the least significant bit of the group ID. A pattern recording area in which the pattern 202 and a part of the absolute pattern 206 are recorded is extracted from the pattern read image (the area extracted in step 306).

  As is apparent from FIG. 7, the recording of the pattern row 206A of the absolute pattern 206 is performed in the presence / absence of ink droplet ejection so that the presence / absence of ink droplet ejection from the nozzle is different between adjacent groups along the main scanning direction. And for each group with ink droplet ejection, each ink droplet is ejected from each nozzle of the group and the ejection of the ink droplet from each nozzle is repeated for a certain time (a certain number of times). Etc., each of the rectangular patterns corresponding to the partial patterns described above is recorded. Therefore, the positions of both ends in the main scanning direction of the individual rectangular patterns constituting the pattern row 206A depend on the pattern recording area by the group corresponding to the rectangular pattern and the group adjacent to the group in the main scanning direction. This corresponds to the boundary position with the pattern recording area. Therefore, as shown in FIG. 10, a single group of pattern recording areas (FIG. 10B) is obtained by using the positions of both ends in the main scanning direction in the rectangular pattern constituting the pattern row 206A as a reference. Can also be extracted.

  Here, in the non-ejection detection pattern 200 shown in FIG. 7, the absolute pattern 206 is disposed at a position adjacent to the incremental pattern 202 (incremental pattern group 204) in the sub-scanning direction, and particularly the absolute pattern. The pattern row 206A 206 is arranged at a position closer to the recording position of the incremental pattern 202 (incremental pattern group 204) than the other pattern rows 206B to 206G (within a predetermined distance and a position of about 12 mm in the first direction). Therefore, the degree of expansion / contraction in the portion of the recording material 114 where the pattern row 206A is recorded is substantially the same as the degree of expansion / contraction in the portion of the recording material 114 where the incremental pattern 202 (incremental pattern group 204) is recorded. equal.

  Further, in the non-ejection detection pattern 200 shown in FIG. 7, since the incremental pattern 202 (incremental pattern group 204) and the absolute pattern 206 are recorded with the same color ink (with the same recording head 160), the recording head In each of the 160 nozzles, the ink droplet landing position is shifted due to the influence of mist or the like when the incremental pattern 202 is recorded, and the incremental pattern 202 is slightly shifted in the sub-scanning direction from the intended position. In the case where the nozzles recorded in the pattern row 206A exist, if ink droplets are ejected from the nozzles during the recording of the pattern row 206A, the ink droplets ejected during the recording of the pattern row 206A are also recorded during the recording of the incremental pattern 202. The landing position shift is similar to

  Therefore, by using the positions of both end portions in the main scanning direction in the rectangular pattern constituting the pattern row 206A as described above as a reference, the ink is not affected by the expansion and contraction of the recording material 114, and by the influence of mist or the like. Even if there is a nozzle in which the landing position of the droplet has shifted, it is possible to accurately extract a pattern recording region of a single group without being affected by the nozzle.

  In step 310, the absolute pattern 206 (pattern strings 206A to 20G) in the pattern recording area extracted in step 308 is converted into a binary group ID, and the group ID corresponds to the pattern recording area extracted in step 308. It is stored in a memory or the like as group specifying information for specifying a group. In step 312, the number of incremental patterns 202 existing in the pattern recording area extracted in step 308 is counted. In step 314, it is determined whether the count result of the incremental pattern 202 in step 312 is equal to the number N of nozzles in a single group. If this determination is affirmative, it can be determined that there are no non-ejection nozzles in the group corresponding to the pattern recording area extracted in step 308, and the process proceeds to step 324.

  If the determination in step 314 is negative, the number of incremental patterns 202 existing in the pattern recording area is smaller than the number N of nozzles in a single group, and corresponds to the pattern recording area extracted in step 308. It can be determined that there are non-ejection nozzles in the group. Therefore, the process proceeds to step 316 to recognize the position in the sub-scanning direction of the incremental pattern 202 that has not been recorded in the pattern recording area. In step 318, based on the position in the sub-scanning direction of the unrecorded incremental pattern 202 recognized in step 316, the nozzles corresponding to the unrecorded incremental pattern 202 in the group corresponding to the extracted pattern recording area (not set). Recognize the nozzle number of the discharge nozzle.

  As shown in FIG. 10B, the incremental pattern 202 by each nozzle in a single group is recorded at different positions along the sub-scanning direction, and each nozzle in the single group is recorded in the incremental pattern. Since the order in which 202 is recorded is known, based on the position in the sub-scanning direction of the unrecorded incremental pattern 202 in the pattern recording area of a single group, the nozzles corresponding to the unrecorded incremental pattern 202 ( The nozzle number of (non-ejection nozzle) can be easily recognized. In step 320, the nozzle number recognized in step 318 and the group specifying information stored in the memory or the like in the previous step 310 are stored in the memory or the like as non-discharge nozzle information for specifying the non-discharge nozzle.

  As described above, in the present embodiment, the position of both ends in the main scanning direction in the rectangular pattern constituting the pattern row 206A of the absolute pattern 206 is used as a reference, and the influence of expansion / contraction of the recording material 114, mist, etc. The pattern recording area of a single group can be accurately extracted without being affected by the nozzle where the ink droplet landing position has shifted due to the influence of the ink droplets. Can be specified.

  In the next step 322, it is determined whether or not the incremental pattern 202 that has not been recorded in the pattern recording area extracted in step 308 and has not been subjected to the processing in steps 316 to 320 remains. This determination is affirmed when the difference between the number of incremental patterns 202 existing in the pattern recording area and the number N of nozzles in a single group is 2 or more in the previous step 314. If the determination in step 322 is affirmed, the process returns to step 316, and steps 316 to 322 are repeated until the determination in step 322 is affirmed. If the determination in step 322 is negative, the process proceeds to step 324.

  In step 324, it is determined whether or not there is a group that has not undergone processing such as detection of non-ejection nozzles in step 308 and subsequent steps among the nozzle groups of the recording head 160 to be detected. If this determination is affirmed, the process returns to step 308, and steps 308 to 324 are repeated until the determination in step 324 is affirmed. As a result, processing such as detection of non-ejection nozzles is performed on all groups of nozzles of the recording head 160 to be detected. Further, when processing such as detection of non-ejection nozzles is completed for all the groups of nozzles of the recording head 160 to be detected, the determination in step 324 is denied and the process proceeds to step 326, and the recording head 160 to be detected With reference to the number of non-ejection nozzles detected, the process branches according to the number of non-ejection nozzles.

  That is, when the number of non-ejection nozzles is 0 (when the non-ejection nozzles are not detected by the recording head 160 to be detected), the process proceeds from step 326 to step 328, and the driving mode of the recording head 160 to be detected is normally set. Set the mode. In this case, when recording an image on the recording material 114, each nozzle of the recording head 106 to be detected is driven as usual.

  If the number of non-ejection nozzles is greater than 0 and less than a preset value, the process proceeds from step 326 to step 330. In this case, although there are non-ejection nozzles in the recording head 106 to be detected, the number of non-ejection nozzles is relatively small. Therefore, in step 330, the non-ejection correction mode is set as the drive mode of the recording head 160 to be detected. Set. In this non-ejection correction mode, when an image is recorded on the recording material 114, the non-ejection nozzle specified by the non-ejection nozzle information stored in the previous step 320 is positioned on both sides of the recording head 106 to be detected. By increasing the ejection amount of ink droplets from the nozzles that are present, non-ejection correction processing is performed to make image defects caused by non-ejection nozzles inconspicuous. This non-ejection correction process may be performed by the print control unit 190 or the head driver 194.

  If the number of non-ejection nozzles is equal to or greater than a preset value, the process proceeds from step 326 to step 336. In this case, even if the non-ejection correction process described above is performed, it can be determined that it is difficult to make the image defect due to the non-ejection nozzle inconspicuous. By performing the preliminary discharge and suction operation, non-ejection recovery processing is performed to try to eliminate the non-ejection state of the non-ejection nozzle. In the next step 338, the non-ejection detection pattern is recorded again on the recording material 114 by the recording head 160 that has performed the non-ejection recovery process, and then the process returns to step 304. As a result, the non-ejection state of the non-ejection nozzles is eliminated by the previous non-ejection recovery process, and it is confirmed whether or not the number of non-ejection nozzles has decreased below a preset value.

  On the other hand, if the number of non-ejection nozzles of the recording head 160 to be detected is less than a preset value, it can be determined that the recording head 160 to be detected can be used for image recording on the recording material 114, so step 328 or step When the processing of 330 is performed, the process proceeds to step 332, and it is determined whether or not the ejection failure nozzle has been detected for all the recording heads 160 of the image recording apparatus 100. If the determination is negative, the process returns to step 306, and the processing after step 306 is performed on the recording head 160 in which no ejection nozzle has not been detected. When it is confirmed that the number of non-ejection nozzles is less than a preset value in all the recording heads 160 of the image recording apparatus 100, the determination in step 332 is affirmed and the process proceeds to step 334, and the leading edge is obtained by the above processing. The image recording by the recording heads 160C to 160B on the image recording area on the recording material 114 in which the non-ejection detection pattern is recorded is started, and the non-ejection detection process is ended.

  In the above description, each time the leading end of the new recording material 114 reaches the position where the recording heads 160C to 160B are disposed, the recording heads 160C to 160B cause the recording heads 160C to 160B to record the non-ejection detection patterns of the respective colors. However, the present invention is not limited to this, and each time the leading end of a new recording material 114 reaches the arrangement position of the recording heads 160C to 160B, the embodiment is described. The non-ejection detection pattern is recorded by some of the recording heads 160C to 160B, and non-ejection nozzles are detected only for some of the recording heads 160 on which the non-ejection detection pattern is recorded. The recording head 160 that performs ejection detection pattern recording and non-ejection nozzle detection may be switched each time.

  Further, in the above, as an example of the second pattern and the third pattern according to the present invention, the absolute pattern is formed by seven pattern rows 206A to 206G arranged along the main scanning direction adjacent to each other in the sub scanning direction. Although the pattern 206 (FIG. 7) has been described, the absolute pattern may be configured by two pattern rows (212A, 212B), for example, the absolute pattern 212 in the non-ejection detection pattern 210 shown in FIG. However, the number of pattern rows constituting the absolute pattern is not limited to the examples shown in FIGS. For example, the absolute pattern 212 shown in FIG. 11 is difficult to represent the group ID because the number of pattern rows is small. Alternatively, the third pattern according to the present invention may be omitted, and only the pattern row corresponding to the second pattern according to the present invention may be recorded.

  In the above description, the mode in which the incremental pattern 202 (incremental pattern group 204) and the absolute pattern 206 are recorded with the same color ink has been described. However, the present invention is not limited to this, and the incremental pattern 202 ( The incremental pattern group 204) and the absolute pattern 206 may be recorded with different color inks (different recording heads 106). In this aspect, if there is a nozzle in which the landing position of the ink droplet has shifted due to the influence of mist or the like in at least one of the plurality of recording heads 106 that record the respective patterns, there is a possibility that the influence will be received. However, by recording each pattern with ink of different colors, an incremental pattern 202 (incremental pattern group 204) and an absolute pattern 206 are recorded as in the non-ejection detection pattern 220 shown in FIG. 12 as an example. It is possible to record in the same area on the material 114 in an overlapping manner. Then, by recording the incremental pattern 202 (incremental pattern group 204) and the absolute pattern 206 in an overlapping manner, the influence of expansion / contraction of the recording material 114 can be eliminated more accurately, and the non-ejection detection pattern can be formed on the recording material. The effect of recording in a narrower area can be obtained. The mode shown in FIG. 12 corresponds to the invention described in claims 6 and 7.

  Further, in the above description, the image recording apparatus 100 configured to move the recording material 114 has been described as an example. However, the present invention is not limited to this, and the recording head is moved in a state where the movement of the recording material is stopped. The present invention is also applicable to an image recording apparatus configured to record an image on a recording material by moving 160 (droplet discharge unit).

  In the above description, the non-ejection detection program according to the present invention has been described as being stored in advance in the program storage unit 182A of the system control unit 182. It is also possible to provide the information recorded in a recording medium such as a ROM.

DESCRIPTION OF SYMBOLS 100 Image recording apparatus 106 Recording head 114 Recording material 144 Inline sensor 161 Nozzle 182 System control part 184 Image memory 190 Print control part 194 Head driver 200 Non-discharge detection pattern 202 Incremental pattern 204 Incremental pattern group 206 Absolute pattern 210 Non-discharge Detection pattern 212 Absolute pattern

Claims (11)

A plurality of nozzles each capable of ejecting droplets so as to adhere to the recording material relatively moved in the first direction are disposed at different positions along a second direction intersecting the first direction. And
The distribution range of the position of the nozzle of the droplet discharge unit along the second direction is divided into a plurality of sections, and the nozzle of the droplet discharge unit is positioned along the second direction of each nozzle On the recording material that is relatively moved in the first direction by sequentially ejecting droplets from the nozzles belonging to the specific group when grouped into a plurality of groups corresponding to the divided individual sections. The recording of the first pattern with the droplets ejected from each nozzle is performed for each of the plurality of groups, and the presence or absence of droplet ejection from the nozzles is performed between adjacent groups along the second direction. Differently, the presence or absence of the droplet ejection is switched in units of groups, and droplets are ejected from each nozzle belonging to a single group with droplet ejection, so that the first pattern on the recording material is ejected. Recording each partial group along the second direction at a position within a predetermined distance along the first direction from the recording position of the ink on each of the groups with droplet discharge. Recording control means for recording a second pattern comprising the partial pattern on the recording material;
Reading means for reading an image recorded on the recording material by the droplet discharge section;
Based on the second pattern of the first pattern and the second pattern read as an image by the reading unit, along the second direction on the image of the first pattern for each group. Determining means for determining a non-ejection state nozzle based on the first pattern existing in the determined recording range;
A liquid droplet ejection apparatus including:   When the number of the first patterns existing in the recording range corresponding to the specific group is smaller than the number of nozzles belonging to the specific group, the specifying unit includes the nozzles belonging to the specific group. It is determined that there is a non-ejection state nozzle, and the reading unit reads the desired recording position within the recording range of each of the first patterns as many as the number of nozzles belonging to the specific group. The liquid droplet ejection apparatus according to claim 1, wherein the nozzle in the non-ejection state is specified based on a recording position where the first pattern does not exist on the image. The recording control unit records a third pattern representing identification information for identifying each of the plurality of groups in combination with the second pattern on the recording material by the droplet discharge unit,
The non-ejection state is determined based on the identification information represented by a combination of the second pattern and the third pattern recorded at a position corresponding to the group in which the non-ejection state nozzle is determined to exist. The droplet discharge device according to claim 2, wherein a group to which the nozzle belongs belongs.   The second pattern represents the value of the least significant bit of the binary number representing the identification information depending on whether or not the partial pattern is recorded, and the third pattern has the number of bits higher than the least significant bit in the binary number. 4. The pattern pattern includes the same number of pattern strings, and each pattern string represents a value of a different bit higher than the least significant bit of the binary number depending on whether or not a partial pattern constituting each pattern string is recorded. Droplet discharge device.   The recording control means applies a partial pattern corresponding to the individual group with droplet ejection out of the second pattern from the same nozzle as the nozzle used when recording the first pattern of the individual group. The liquid droplet ejection apparatus according to claim 1, wherein the liquid droplets are ejected and recorded. A plurality of the droplet discharge portions that discharge droplets of different colors,
The recording control means records the first pattern on the recording material using the first droplet discharge portion among the plurality of droplet discharge portions, and is different from the first droplet discharge portion. 5. The droplet discharge device according to claim 1, wherein the second pattern is recorded on the recording material using two droplet discharge units.   The liquid droplet ejection apparatus according to claim 6, wherein the recording control unit records the second pattern so as to overlap the first pattern within a recording range of the first pattern on the recording material. The reading means reads the image recorded on the recording material by dividing it into at least a plurality of pixels arranged along the second direction,
The recording control means has a recording interval of the first pattern along the second direction on the recording material in the second direction of a reading range on the recording material by a single pixel of the reading means. The liquid droplet ejection apparatus according to claim 1, wherein the first pattern is recorded on the recording material so as to be larger than a size along the line. The reading means reads the image recorded on the recording material by dividing it into at least a plurality of pixels arranged along the second direction,
In the recording control unit, the size of the first pattern along the first direction on the recording material is along the first direction of the reading range on the recording material by a single pixel of the reading unit. The liquid droplet ejection apparatus according to claim 1, wherein the first pattern is recorded on the recording material so as to be larger than a size. A plurality of nozzles each capable of ejecting droplets so as to adhere to the recording material relatively moved in the first direction are disposed at different positions along a second direction intersecting the first direction. The computer of the liquid droplet ejection apparatus, comprising: a reading unit that reads an image recorded on the recording material by the liquid droplet ejection unit;
The distribution range of the position of the nozzle of the droplet discharge unit along the second direction is divided into a plurality of sections, and the nozzle of the droplet discharge unit is positioned along the second direction of each nozzle On the recording material that is relatively moved in the first direction by sequentially ejecting droplets from the nozzles belonging to the specific group when grouped into a plurality of groups corresponding to the divided individual sections. The recording of the first pattern with the droplets ejected from each nozzle is performed for each of the plurality of groups, and the presence or absence of droplet ejection from the nozzles is performed between adjacent groups along the second direction. Differently, the presence or absence of the droplet ejection is switched in units of groups, and droplets are ejected from each nozzle belonging to a single group with droplet ejection, so that the first pattern on the recording material is ejected. Recording each partial group along the second direction at a position within a predetermined distance along the first direction from the recording position of the ink on each of the groups with droplet discharge. A second pattern consisting of the partial pattern is recorded on the recording material,
Based on the second pattern of the first pattern and the second pattern read as an image by the reading unit, along the second direction on the image of the first pattern for each group. A non-ejection detection method for determining a non-ejection state nozzle based on the first pattern existing in the judged recording range. A plurality of nozzles each capable of ejecting droplets so as to adhere to the recording material relatively moved in the first direction are disposed at different positions along a second direction intersecting the first direction. A computer for a droplet discharge device, comprising: a reading unit that reads an image recorded on the recording material by the droplet discharge unit;
The distribution range of the position of the nozzle of the droplet discharge unit along the second direction is divided into a plurality of sections, and the nozzle of the droplet discharge unit is positioned along the second direction of each nozzle On the recording material that is relatively moved in the first direction by sequentially ejecting droplets from the nozzles belonging to the specific group when grouped into a plurality of groups corresponding to the divided individual sections. The recording of the first pattern with the droplets ejected from each nozzle is performed for each of the plurality of groups, and the presence or absence of droplet ejection from the nozzles is performed between adjacent groups along the second direction. Differently, the presence or absence of the droplet ejection is switched in units of groups, and droplets are ejected from each nozzle belonging to a single group with droplet ejection, so that the first pattern on the recording material is ejected. Recording each partial group along the second direction at a position within a predetermined distance along the first direction from the recording position of the ink on each of the groups with droplet discharge. Recording control means for recording the second pattern consisting of the partial pattern on the recording material,
The second direction on the image of the first pattern for each group based on the second pattern of the first pattern and the second pattern read as an image by the reading unit A non-ejection detection program for functioning as a specifying unit that judges a recording range along the line and identifies a nozzle in a non-ejection state based on the first pattern existing in the judged recording range.

Images