JP2011218584A - Position correcting method and device, for printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve precise alignment, regardless of a thickness difference between a plate and a print object.SOLUTION: A second-layer printing pattern and a second-layer alignment mark are printed on a temporary print object held on an alignment stage for the plate by means of a second-layer plate for superposition-printing held on an alignment stage for the print object. It is determined whether or not the alignment mark on the temporary print object in the alignment area is in the sight of an alignment camera. When the alignment mark is not in the sight of the camera, an alignment operation for the temporary print object is performed so that the alignment mark may be within the sight of the camera, thereafter, the alignment operation for the second-layer plate is performed in the same manner. When the temporary print object in the alignment area is in the sight of the alignment camera, the position is set to a target position, thereafter, regarding the print object whose first-layer plate is already printed, the alignment mark is corrected so as to be in the target position. Then, offset printing is made to start.

Description

  The present invention relates to a position correction method and apparatus for a printing apparatus used for correcting a position of a printing plate and a printing target in order to prevent a displacement of a printing position in the printing apparatus.

  In recent years, instead of fine processing such as etching of metal vapor deposition film, printing technology using conductive paste as printing ink, for example, intaglio offset printing technology, electronic circuits of image display elements such as liquid crystal displays on a substrate A method of forming by printing has been proposed.

  When the electronic circuit of the image display element is formed on a substrate, a fine line width of about 10 μm, for example, may be required as an electrode line width. In addition, a plurality of electronic circuits may be formed on the substrate in a superimposed manner. In this case, the overprinting of the electronic circuits is performed by replacing the plate. However, if the printing position is shifted, the entire configuration of the electronic circuits is destroyed. However, in the case of a precise electronic circuit in which the line width is about 10 μm, the positional deviation of the overlapping print position can be suppressed from several μm to sub-μm order. Sometimes it is needed.

  For this reason, when an electronic circuit is formed on the substrate by printing, higher printing accuracy is required as compared with normal offset printing in which characters and images are printed on paper or the like.

  In general, in offset printing, it is more reproducible to print patterns by transfer (acceptance) and retransfer (printing) by offset printing when the same shape is used for the plate and printing object. When printing a precise printing pattern such as that described above, it is advantageous to use a flat plate.

  Conventionally, as an offset printing apparatus using a flat plate and an object to be printed, for example, a guide rail extending in one direction is provided on the upper side of a horizontal base (base), and can reciprocate along the guide rail. A flat plate (master plate) and an object to be printed (work plate) are placed on a movable table along the moving direction at a predetermined interval, and further, the plate and the printing in the longitudinal direction of the guide rail are printed. There is a configuration in which a blanket roll (roller transfer cylinder) is provided above the guide rail so that the object can be moved together.

  According to the offset printing apparatus having such a configuration, when the inking plate and the printing target are sequentially passed through the position immediately below the blanket roll as the print target moves along the guide rail of the moving table, the rolling is performed. The blanket roll is brought into contact with the printing plate and the printing target in order from above, so that the ink is transferred (received) from the inked printing plate to the surface of the blanket roll. Offset printing can be performed by performing a retransfer (printing) process of ink from the roll surface to the printing target.

  By the way, in order to prevent the positional deviation of the print pattern printed on the printing object in the offset printing apparatus, it is necessary to perform initial alignment between the plate and the printing object.

  In particular, when overlay printing is performed, the plate is replaced each time the printing pattern of each layer is printed, and therefore it is necessary to perform initial alignment for the replaced plate. In addition, in order to prevent misalignment when superimposing a print pattern that has already been printed and a print pattern to be newly printed on each print target for printing the second and subsequent print patterns in the superposition printing. , It will be necessary to align.

  Even when the plate is once removed for the cleaning process or the like by the offset printing apparatus and then reused, it is necessary to align the plate.

  Therefore, as a means for aligning the plate and the printing target in the offset printing apparatus having the above-described configuration, for example, the plate and the printing target are both provided with alignment marks on the surface thereof, In addition, on the moving table, there are provided individual position correcting means for the plate and the printing object, and the plate and the printing object are positioned above the position where the plate and the printing object can move in the longitudinal direction of the guide rail. As a configuration provided with an alignment camera (image sensor) for detecting an alignment mark, when the alignment mark of the plate is detected by the alignment camera, the position of the detected alignment mark is set in advance. The amount of deviation from the position (target position) is detected and the amount of deviation is eliminated. To correct the position of the plate by the position correcting means for urchin version.

  Furthermore, when the alignment mark to be printed is detected by the alignment camera, the amount of deviation from a predetermined position (target position) similar to the case of the plate is detected for the position of the detected alignment mark, A technique is adopted in which the position of the printing object is corrected by the position correcting means for the printing object so that the deviation amount is eliminated, thereby improving the positioning accuracy between the plate and the printing object. (For example, see Patent Document 1).

JP-A-5-185586

  However, in order to print a precise print pattern as in the case where an electronic circuit is formed on a substrate by printing, as described above, it is very difficult to suppress the positional deviation of the print position from several μm to sub-μm order. Therefore, it is necessary to perform precise alignment. In order to perform such precise alignment, it is necessary to use a high-magnification camera with a high resolution as an alignment camera for photographing the alignment mark. With this type of alignment camera, the depth of field is For example, it may be as narrow as several tens of μm.

  Therefore, if there is a difference in thickness between the plate used for offset printing and the printing target, the plate and the printing target placed on the moving table at the same height position via the position correction means are at the surface height position of each other. Because the difference arises, if the difference in surface height position deviates from the recognizable distance range of the alignment camera determined according to the depth of field, the alignment mark of the plate and the alignment mark to be printed are The actual situation is that it cannot be detected by the same alignment camera.

  In addition, as a countermeasure for the problem caused by the difference between the thickness dimension of the plate and the print target as described above, when the plate and the print target are placed on the moving table via the position correction unit, individual position correction is performed. It is conceivable to adjust the height of the means with a shim or the like so that the difference in surface height position between the plate and the substrate is made minute. According to this method, even with an alignment camera having a narrow depth of field, it is possible to detect the alignment marks on both the plate and the substrate having a difference in thickness. However, in the above method, each time the plate used or the thickness dimension of the printing target is changed, the height of the individual position correction means is adjusted so that the difference in the surface height position between the plate and the substrate becomes small. Since it is necessary to do this, there is a problem that time and labor are increased.

  Therefore, the present invention requires adjustment of the height of the place where the plate and the printing target are placed even if there is a difference in thickness dimension that deviates from the recognizable distance of the alignment camera between the plate and the printing target. And a position correction method and apparatus for a printing apparatus that can be easily aligned with each other and can be advantageous when printing a precise printing pattern with high accuracy. It is.

  In order to solve the above-described problem, the present invention corresponds to claim 1 and the temporary print target having the same thickness dimension as the true print target and not having the alignment mark on the alignment stage for the print target. Is printed on the printing plate and the alignment mark held on the plate alignment stage with a blanket roll on the temporary printing target, and then the temporary printing target. It is determined whether or not the position of the alignment mark printed on the image is within the field of view of the alignment camera. If the position is not within the field of view, the position of the alignment mark of the temporary print target is determined by the alignment stage for the print target. An alignment operation is performed to correct the position of the temporary print target so that it is within the field of view of the alignment camera, and the plate If the position of the alignment mark of the temporary print object is within the field of view of the alignment camera, the alignment stage is caused to perform an alignment operation similar to the alignment operation of the alignment stage for the print object. The position of the alignment mark of the temporary print target in the camera's field of view is set as the target position, and then a true alignment mark corresponding to the alignment mark of the plate is previously provided on the alignment stage for the print target. After holding the print object, the alignment stage for the print object performs alignment for correcting the position of the true print object so that the position of the alignment mark of the true print object matches the target position, After that, the above alignment A printing apparatus that performs offset printing via a blanket roll using a plate held on an alignment stage for a plate after printing and a printing object after alignment on the alignment stage for printing. The position correction method is used.

  According to a second aspect of the present invention, the blanket roll is sequentially brought into contact with the plate held on the plate alignment stage and the printing target held on the printing target alignment stage holding the printing target from above. Same as the true printing object for holding the printing pattern and the alignment mark of the plate on the alignment stage for the printing object in the offset printing apparatus that can perform the offset printing process on the printing object instead of the true printing object. Temporary printing object having a thickness dimension and no alignment mark, alignment mark provided in advance on the true printing object held on the alignment stage for the printing object, and the temporary printing object An alignment camera for detecting an alignment mark to be printed from the plate, and the above-mentioned alarm. A controller for giving a command to the alignment stage for the printing object and the alignment stage for the plate based on the information on the position of the alignment mark in the true printing object and the temporary printing object detected by the attachment camera. A position correction apparatus for a printing apparatus having the above configuration.

  Furthermore, the controller in the above configuration has the alignment mark printed from the plate on the temporary printing object in the field of view of the alignment camera when the temporary printing object is held on the alignment stage for the printing object. A function for determining whether or not the alignment mark on the temporary print target is not within the field of view of the alignment camera, so that the alignment mark on the temporary print target is within the field of view of the alignment camera. Alignment operation of the alignment stage for the printing target, and then the alignment mark for the temporary printing target is aligned with the function of causing the alignment stage for the printing plate to perform the same alignment operation as the alignment stage for the printing target. If it is determined that you are within the field of view of the camera In the state where the position of the alignment mark is set as a target position and the true print target is held on the alignment stage for the print target, the true printing detected by the alignment camera is performed. The configuration is such that the position of the alignment mark provided in advance on the object is aligned with the alignment stage for the print object so as to coincide with the target position.

According to the present invention, the following excellent effects are exhibited.
(1) In a state where a temporary printing object having the same thickness dimension as the true printing object and not having an alignment mark is held on the alignment stage for the printing object, The printing pattern and alignment mark on the plate held on the alignment stage for printing are printed via a blanket roll, and then the position of the alignment mark printed on the temporary printing object is within the field of view of the alignment camera. If it is not within the field of view, the position of the temporary print object is adjusted by the alignment stage for the print object so that the position of the alignment mark of the temporary print object is within the field of view of the alignment camera. In addition to performing an alignment operation to be corrected, the alignment stage for the plate is aligned with the alignment stage for the plate. If the position of the alignment mark of the provisional print target is within the field of view of the alignment camera, then the provisional print target within the field of view of the alignment camera is performed. The position of the alignment mark is set as the target position, and then the true print target provided with the alignment mark corresponding to the alignment mark of the plate is previously held on the alignment stage for the print target. Alignment for correcting the position of the true printing object is performed by the alignment stage for printing object so that the position of the alignment mark of the true printing object coincides with the target position, and then for the plate after the alignment operation. Is held on the alignment stage And using the printing target after alignment on the alignment stage for the printing target as a position correction method for a printing apparatus that performs offset printing via a blanket roll, a plate provided with an alignment mark, Precise alignment based on the position information of the alignment mark on the print target side detected by the alignment camera can be performed on the print target provided with the alignment mark in advance.
(2) Moreover, it is possible to eliminate the need for the alignment camera to detect the plate alignment marks. Therefore, even if there is a difference that deviates from the recognizable distance range of the alignment camera determined according to the depth of field of the alignment camera in the thickness dimension of the plate and the printing object, the plate and It is possible to align the print target.
(3) Therefore, an electronic circuit is formed on a substrate by printing so that a high-resolution alignment camera is required even if the depth of field is narrow in order to detect an alignment mark provided on a plate or a printing target. This can be an advantageous method when printing a precise print pattern such as when performing the above.
(4) A plate pattern held on the plate alignment stage and a printing target held on the printing target alignment stage holding the printing target are sequentially brought into contact with a blanket roll from above to print the printing pattern and alignment mark on the plate. In the offset printing apparatus in which offset printing processing can be performed on the printing object, the alignment has the same thickness dimension as that of the true printing object and is held on the alignment stage for the printing object instead of the true printing object. Temporary printing object not provided with a mark, an alignment mark provided in advance on the true printing object held on the alignment stage for the printing object, and an alignment mark printed from the plate on the temporary printing object And an alignment camera for detecting A configuration comprising: an alignment stage for the printing object, and a controller for giving a command to the plate alignment stage based on the information on the position of the alignment mark in the detected true printing object and temporary printing object. The position correction device of the printing apparatus, more specifically, the controller in the above configuration prints from the plate on the temporary print target in a state where the temporary print target is held on the alignment stage for the print target. A function for determining whether or not the alignment mark is within the visual field of the alignment camera, and if it is determined that the alignment mark in the temporary printing object is not within the visual field of the alignment camera, Align the alignment stage for the print target so that the alignment mark is within the field of view of the alignment camera. After performing the print operation, it is determined that the alignment operation similar to the alignment operation of the alignment stage for the printing target is performed on the plate alignment stage, and that the alignment mark on the temporary printing target is within the field of view of the alignment camera. In this case, it functions to set the position of the alignment mark as a target position, and in the state where the true print target is held on the alignment stage for the print target, it is detected by the alignment camera. A position correction device for a printing apparatus having a function of performing an alignment operation on an alignment stage for a printing target so that the position of an alignment mark provided in advance on the true printing target matches the target position; As a result, the position of the printing apparatus (1) is compensated. A device configuration for implementing the correct method can be easily realized.

FIG. 5 is a diagram illustrating a flow of a processing procedure according to an embodiment of a position correction method for a printing apparatus of the present invention. It is a schematic side view which shows the offset printing apparatus provided with the position correction apparatus of the printing apparatus used for implementation of the method of FIG. FIG. 1 shows a state in which the second layer plate is held on the plate table in step B1 in the method of FIG. 1 and the temporary print target is held on the print target table in step B2, wherein (a) is a schematic side view. FIG. 4B is a schematic view showing the upper surface of the plate, FIG. 5C is an image recognized by the image processing apparatus, and FIG. 1 shows a state in which the second layer printing pattern of the second layer plate on the plate table is printed on the printing target table in Step B3 in the method of FIG. 1, wherein (a) is a schematic side view. FIG. 4B is a schematic view showing the upper surface of the plate, FIG. 5C is an image recognized by the image processing apparatus, and FIG. As a procedure following FIG. 4 in the method of FIG. 1, a temporary print target on which a second layer print pattern is printed is moved to the alignment area together with the print target table, (a) is a schematic side view, (B) is an upper surface of the plate, and (c) is a schematic diagram showing an image recognized by the image processing apparatus. For correcting the position of the temporary print target by the alignment stage for the print target based on the position recognized by the image processing apparatus of the alignment mark for the second layer in the temporary print target in Step B6 in the method of FIG. FIG. 5A shows a state in which an alignment operation is performed. FIG. 5A is a schematic side view, FIG. 5B is a schematic view showing an image recognized by the image processing apparatus, and FIG. 1A and 1B show a state where an alignment operation is performed by a plate alignment stage in step B7 in the method of FIG. 1 to correct the position of the second layer plate, where FIG. 1A is a schematic side view, and FIG. , (C) is a schematic diagram showing images recognized by the image processing apparatus. The state in which the second layer printing pattern of the second layer plate is printed in step B3 on the temporary printing object newly held on the printing object table in step B2 as the procedure following step B7 in the method of FIG. (A) is a schematic side view, (b) is an upper surface of a plate, (c) is an image recognized by the image processing apparatus, and (d) is a schematic diagram showing an upper surface of a provisional print target. It is. 1 shows a state in which the position recognized by the image processing apparatus of the alignment mark for the second layer in the temporary printing target in step B8 in the method of FIG. 1 is set as the target position, (a) is a schematic side view, (b) ) Is an upper surface of the plate, and (c) is a schematic diagram showing an image recognized by the image processing apparatus. 1 shows a state in which the first layer printed printed object that is the true printing object is held on the printing object table in step B9 in the method of FIG. 1, (a) is a schematic side view, (b) is a plate of the plate (C) is a schematic diagram showing an image recognized by the image processing apparatus, and (d) is a schematic diagram showing an upper surface of a printing target printed on the first layer. 1 shows a state in which the position of the alignment mark for the second layer on the print target printed on the first layer on the print target table is corrected in step B10 so as to coincide with the target position. Is a schematic side view, (b) is an upper surface of the plate, and (c) is a schematic diagram showing an image recognized by the image processing apparatus. 1 shows a state in which the second layer printing pattern of the second layer printing plate is superimposed and printed on the printing target of the first layer printed in step B11 in the method of FIG. 1, (a) is a schematic side view, (b) Is an upper surface of the plate, (c) is an image recognized by the image processing apparatus, and (d) is a schematic diagram showing an upper surface of the print target that is overprinted.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIGS. 1 to 12 (a), (b), (c), and (d) have an alignment mark in an offset printing apparatus as shown in FIG. 2 as an embodiment of the position correction method and apparatus of the printing apparatus of the present invention. As a true printing target having a plate and an alignment mark in advance, for example, two layers comprising a second layer printing pattern P2 and second layer alignment mark 2 for performing the second layer printing in the overlay printing For the second layer for aligning with the second layer alignment mark 2 of the second layer plate 1 when the first plate 1 and the first layer printing pattern P1 are printed on the original printing target. An application example in the case where alignment with the printed object 3 printed on the first layer formed by printing the alignment mark 4 at the same time is shown as follows.

  Here, first, the offset printing apparatus shown in FIG. 2 will be outlined. In the offset printing apparatus, a guide rail 6 extending in one direction is provided on the upper side of the horizontal base 5. The guide rail 6 has a flat plate 1 (for the sake of convenience, the same reference numerals as those of the second layer plate) and a flat print object 3 such as a substrate (for the sake of convenience, the first layer printed) For example, a plate table 7 and a print target table 8 that can hold the plate 1 and the print target 3 individually, respectively, are used as a moving table for holding the same). It can be attached independently by reciprocating (running).

  Further, a blanket as a printing roll that extends in a direction perpendicular to the longitudinal direction of the guide rail 6 and in a horizontal direction above a halfway point along which the plate table 7 and the printing target table 8 can travel together in the longitudinal direction of the guide rail 6. The roll 9 is configured to be rotatable by a rotary drive mechanism (not shown) and to be lifted and lowered by a lift drive mechanism (not shown).

  Furthermore, the required dimension is located at another intermediate position where the plate table 7 can travel in the longitudinal direction of the guide rail 6, for example, to one end side in the longitudinal direction of the guide rail 6 (left side in the drawing) from the place where the blanket roll 9 is installed. An inking device 10 for performing inking with respect to the plate 1 held on the plate table 7 is provided at a required position on the stand 5 at a remote position.

  Thus, after inking the plate 1 held on the plate table 7 by the inking device 10, the plate table 7 holding the inked plate 1 and the print target table holding the print target 3. 8 is passed through the guide rail 6 in the same direction and directly below the blanket roll 9 in the same direction, the blanket roll 9 in a state of being rolled by the rotation driving mechanism (not shown) is moved up and down (not shown). The ink is lowered by the drive mechanism so as to contact the inked plate 1 from above, and then the blanket roll 9 is brought into contact with the printing object 3 from above so that ink (from the plate 1 to the blanket roll 9 ( (Print pattern) transfer (acceptance) processing and retransfer of the ink (print pattern) from the blanket roll 9 to the print target 3 Print) processing to perform the in are to be able to carry out the offset printing process.

  The position correction apparatus for a printing apparatus according to the present invention applied to the offset printing apparatus having the above-described configuration uses the plate table 7 and the printing target table 8 as position correction means at the upper part of each, for example, free in three axis directions of XYθ. As an arrangement in which alignment stages 7a and 8a for a plate and a printing object having a degree are integrally provided, the plate 1 and the printing object 3 can be placed and held on the upper side of the alignment stages 7a and 8a. It is.

  Further, another halfway position where the printing target table 8 can travel in the longitudinal direction of the guide rail 6, for example, the other end side in the longitudinal direction of the guide rail 6 from the installation position of the blanket roll 9 (right side in the drawing). An alignment area 11 is provided at a required position on the gantry 5 at a position away from the required dimension. In the alignment area 11, the alignment mark 4 provided on the print target 3 held on the print target table 8 in a state where the print target table 8 is stopped at a predetermined position of the guide rail 6 ( Alignment cameras 12 and 13 are provided for detecting (photographing) from the upper side (same reference numerals as those of the second layer alignment mark).

  The alignment cameras 12 and 13 are provided, for example, so that four alignment marks 4 provided on the square portions of the printing object 3 can be individually detected, and two of the diagonal positions are the positions of the printing positions. A high-resolution alignment camera 12 having a high resolution required to perform a very precise alignment that suppresses the deviation from several μm to a sub-μm order, and the remaining two have a wider field of view 13a (FIG. 6C). ))).

  Each of the alignment cameras 12 and 13 is connected to an image processing device 14 for recognizing the position of the alignment mark 4 of the printing object 3, and further, the alignment mark 4 input from the image processing device 14 Based on the position information, the controller 15 is provided with a controller 15 for giving a command to the alignment stage 7a of the plate table 7 and the alignment stage 8a of the printing target table 8.

  Next, the function of the controller 15 will be described together with the procedure of the position correction method for the printing apparatus of the present invention.

  In the following, as described above, the single line printing process (the first layer printing process in the superposition printing) shown on the left side of the one-dot chain line in FIG. 1, that is, the first layer on the plate table 7. A plate (not shown) is placed and held (step A1: SA1), and a plain print object (not shown) such as a substrate is placed and held on the print object table 8 (step A2: SA2) Next, using the first layer plate held on the plate table 7 and the raw print target held on the print target table 8, the same offset printing process as described above is performed to obtain 1 A layer printing pattern is printed (step A3: SA3), and the first layer printing pattern P1 and the second layer alignment mark 4 of the first layer plate are used as a true printing object previously provided with an alignment mark. Example was the first layer printed print target 3 is assumed to is formed (Step A4: SA4).

  When the overlay printing process shown on the right side of the one-dot chain line in FIG. 1 is performed on the first layer printed object 3, first, FIGS. 3A, 3 B, 3 C, and 3 D are performed. As shown in FIG. 2, on the plate table 7, a second layer plate 1 having a second layer printing pattern P2 and a second layer alignment mark 2 is installed instead of the first layer plate ( Step B1: SB1). Further, on the printing target table 8, as a temporary printing target 3A having the same thickness dimension as the true printing target and not provided with the alignment mark, for example, a plain printing target not subjected to the printing process is held ( Step B2: SB2).

  3B is a schematic diagram showing the upper surface of the second layer plate 1 held on the plate table 7, and FIG. 3C is recognized by the image processing apparatus 14 at that time. FIG. 3D is a schematic diagram showing an upper surface of the provisional print target 3A held on the print target table 8 at that time. 4 (a) (b) (c) (d) to FIG. 12 (a) (b) (c) (d) described later are the same as FIGS. 3 (b) (c) (d). FIGS. 10A and 10B are diagrams showing the same parts as FIGS. 3B, 3C, and 3D (FIGS. 10D and 12D are on the print target table 8). It is a schematic diagram showing the top surface of the true print object 3). Therefore, in the following, description of each figure number indicated by an alphabet in each figure is omitted.

  Next, as shown in FIGS. 4A, 4B, 4C, and 4D, an offset printing process similar to that described above is performed using the second-layer plate 1 and the temporary printing target 3A. Then, the second layer printing pattern P2 and the second layer alignment mark 4 are printed on the temporary printing object 3A from the second layer plate 1 (step B3: SB3).

  When the second layer alignment mark 4 is provided on the temporary print object 3A by the offset printing process in step B3 (SB3), the print object is displayed as shown in FIGS. 5 (a), 5 (b), and 5 (c). The table 8 is moved to the alignment area 11.

  Next, as shown in FIGS. 6A, 6 </ b> B, and 6 </ b> C, based on the images of the alignment cameras 12 and 13 that photograph the temporary print target 3 </ b> A on the print target table 8 arranged in the alignment area 11. Then, the image processing device 14 recognizes the temporary print target 3A (step B4: SB4), and the second layer alignment mark 4 provided on the temporary print target 3A corresponds to the corresponding high-resolution alignment camera 12. Is determined to be within the visual field 12a (step B5: SB5).

  If it is determined in step B5 (SB5) that the second layer alignment mark 4 in the temporary print target 3A is not within the field of view 12a of the corresponding high-resolution alignment camera 12, step B6 (SB6) The controller 15 gives a command to the alignment stage 8a of the print target table 8 by the controller 15 based on the information on the position of the alignment mark 4 for the second layer in the print target 3A input from the image processing device 14. The position of the temporary print object 3A is set in three axial directions of XYθ so that the second-layer alignment mark 4 provided on the temporary print object 3A is within the field of view of the corresponding high-resolution alignment camera 12. The alignment operation to be corrected is performed.

  At this time, when a part of the corresponding second-layer alignment mark 4 is hung on the field of view of the high-resolution alignment camera 12, the field of view of the high-resolution alignment camera 12 to which the second-layer alignment mark 4 corresponds. What is necessary is just to correct | amend the position of the said temporary printing target 3A so that it may completely fit in 12a. When the second layer alignment mark 4 is completely out of the field 12a of the corresponding high resolution alignment camera 12, the second layer alignment mark 4 detected by the field 13a of the wide field alignment camera 13 is used. The position of the temporary print object 3A is corrected with such an accuracy that a part of the alignment mark 4 for the second layer corresponding to the field of view of the high-resolution alignment camera 12 is suspended. Therefore, an alignment operation for further correcting the position of the temporary printing object 3A may be performed so that the second-layer alignment mark 4 is completely within the field of view 12a of the corresponding high-resolution alignment camera 12. .

  In step B6 (SB6), when the alignment operation for correcting the position of the temporary print target 3A by the alignment stage 8a of the print target table 8 is completed, the controller 15 performs the steps shown in FIGS. As shown in c), a command is given to the alignment stage 7a of the plate table 7, and the same operation as the alignment operation in the three-axis directions of XYθ of the alignment stage 8a of the printing target table 8 performed in step B6 (SB6). The alignment operation is performed on the plate alignment stage 7a (step B7: SB7). As a result, in the second layer plate 1 held on the plate table 7, the position of the second layer alignment mark 2 is printed on the temporary print object 3A detected by the image detection device 14. Correction is performed in the same manner as the position of the provided second layer alignment mark 4.

  After step B7 (SB7), the process returns to step B2 (SB2), and a new temporary table is displayed on the print target table 8 as shown in FIGS. 8 (a), (b), (c), and (d). After the printing object 3A is installed and held, the offset printing process similar to that described above is performed on the temporary printing object 3A using the second layer plate 1 whose position is corrected in step B7 (SB7). After the second temporary printing object 3A is printed, the second layer printing pattern P2 and the second layer alignment mark 4 are printed from the second layer printing plate 1 (step B3: SB3), and then the two layers are printed. The temporary printing object 3A provided with the eye alignment mark 4 by printing is moved to the alignment area 11 together with the printing object table 8, and the image processing apparatus 14 connected to the alignment cameras 12 and 13 performs the above operation. The temporary printing object 3A on the printing object table 8 is recognized (step B4: SB4), and it is again determined whether or not the second layer alignment mark 4 is within the field of view 12a of the corresponding high resolution alignment camera 12. If it is judged (step B5: SB5) and it is not within the field of view 12a, the alignment mark 4 for the second layer provided by printing on the temporary print object 3A is within the field of view 12a of the corresponding high resolution alignment camera 12. The process of step B6 (SB6), step B7 (SB7), and step B2 (SB2) to step B5 (SB5) is sequentially repeated until they are settled.

  In step B5 (SB5), as shown in FIGS. 9A, 9B, and 9C, the high-resolution alignment camera to which the alignment mark 4 for the second layer provided by printing on the temporary print target 3A corresponds. If it is determined that the image is within the 12 fields of view 12a, the process proceeds to step B8 (SB8), and the controller 15 determines that 2 in the temporary print target 3A recognized by the image processing device 14 at that time. The position of the layer alignment mark 4 is set to the target position 16.

  At this time, the position of the second layer alignment mark 4 provided by printing on the temporary printing object 3A is set as the target position 16 based on the second layer alignment mark 2 of the second layer plate 1. Therefore, the position of the second layer alignment mark 2 in the second layer plate 1 is naturally arranged corresponding to the target position 16.

  Therefore, after that, as shown in FIGS. 10A, 10B, 10C, and 10D, one layer is formed on the print target table 8 by the single-line printing process of steps A1 (SA1) to A3 (SA3). The first layer printed print target 3 which is a true print target on which the eye print pattern P1 and the second layer alignment mark 4 have been printed is placed and held (step B9: SB9), and then FIG. a) As shown in (b) and (c), the printing object table 8 holding the first layer printed object 3 is moved to the alignment area 11.

  In this state, when the image processing device 14 connected to each of the alignment cameras 12 and 13 recognizes the first layer printed print target 3 on the print target table 8, the controller 15 performs the image processing. Based on the position information of the alignment mark 4 for the second layer on the printed target 3 printed on the first layer input from the apparatus 14, a command is given to the alignment stage 8a of the printing target table 8 to print the first layer. The position of the first layer printed print object 3 is set in three axial directions of XYθ so that the second layer alignment mark 4 provided on the printed object 3 matches the target position 16 set in step B8 (SB8). The alignment operation to be corrected is performed (step B10: SB10).

  The alignment operation for correcting the position of the print target 3 printed on the first layer is detected by the visual field 12a of the high-resolution alignment camera 12 and the visual field 13a of the wide-field alignment camera 13 (see FIG. 6C). Based on the position of the alignment mark 4 for the second layer in the printed target 3 printed on the first layer, the same as the alignment operation when the position of the temporary printed object 3A is corrected in step B6 (SB6). You can make it happen.

  As a result, the second-layer plate 1 and the second-layer alignment marks 2 and 4 in the first-layer printed object 3 are both arranged corresponding to the target position 16.

  Thereafter, as shown in FIGS. 12A, 12B, 12C, and 12D, the same offset printing as described above is performed by using the second layer plate 1 and the first layer printed target 3. By executing the process, the second layer printing pattern P2 of the second layer printing plate 1 is overlaid on the first layer printing pattern P1 in the first layer printed target 3 (step S1). B11: SB11).

  As described above, accurate alignment of the second layer alignment mark 2 of the second layer plate 1 and the second layer alignment mark 4 of the first layer printed target 3 via the target position 16 is performed. Under such conditions, the second layer printing pattern P2 of the second layer printing plate 1 is accurately overprinted with respect to the first layer printing pattern P1 in the first layer printed target 3. become.

  Thus, according to the position correction method and apparatus of the printing apparatus of the present invention, the second layer plate 1 including the second layer alignment mark 2 as the plate including the alignment mark, and the alignment mark are provided in advance. Based on the positional information of the alignment mark 4 on the print target 3 side detected by the high resolution alignment camera 12 for the first layer printed print target 3 having the second layer alignment mark 4 as the print target. Precise alignment can be achieved.

  Moreover, the operation procedure for aligning the second-layer plate 1 and the first-layer printed object 3 is determined by the alignment cameras 12 and 13 of the second-layer alignment mark 2 in the second-layer plate 1. Detection and recognition by the image processing device 14 can be made unnecessary.

  Therefore, the high-resolution alignment camera 12 is determined according to the depth of field of the high-resolution alignment camera 12 used in the alignment area 11 in the thickness dimension of the second-layer plate 1 and the first-layer printed object 3. Even if there is a difference that deviates from the recognizable distance range, the second layer plate 1 and the first layer printed object 3 can be aligned without any problem.

  Therefore, in order to detect an alignment mark, a high-precision alignment camera 12 is required even if the depth of field is narrow. This can be advantageous when printing is performed.

  The present invention is not limited only to the above-described embodiment, and a flat plate 1 provided with an alignment mark so that the alignment mark can be printed on the print target 3 together with the print pattern. If the offset printing is performed using the printing object 3 provided with the alignment mark corresponding to the alignment mark of the plate 1 in advance, the alignment for the printing of the third and subsequent layers in the overlay printing is performed. You may apply.

  Furthermore, the present invention may be applied to the case where alignment is performed between the plate 1 and the printing object 3 in the case of performing the first layer in the superposition printing or the single line printing process that is single phase printing. In this case, an alignment mark is provided in advance on the true print target 3 before printing by means other than printing from the plate 1, and the alignment mark has the same thickness dimension as the true print target. It is sufficient to prepare a provisional printing object that does not include the above.

  The positions of the alignment marks 2 and 4 provided on the plate 1 and the printing target 3 may be changed as appropriate. Further, the number of alignment marks 2 and 4 may be increased or decreased as appropriate according to the number of target positions 16 required for accurate alignment of the plate 1 and the printing object 3.

  Depending on the position and number of the alignment marks 2 and 4, the position and number of the alignment cameras 12 and 13 provided in the alignment area 11 may be appropriately changed.

  If the position correction method and apparatus of the printing apparatus of the present invention are configured to hold the flat plate 1 and the flat print object 3 so that the position can be individually corrected, the plate 1 and the print object 3 are shared. A blanket roll 9 provided in a movable manner is sequentially applied to the plate 1 and the printing target 3 held on the fixed table via the individual alignment stage or the plate 1 held on the fixed side via the individual alignment stage. The present invention may be applied to any type of offset printing apparatus other than the one shown in the figure, such as an offset printing apparatus of a type that is brought into contact.

  Of course, various modifications can be made without departing from the scope of the present invention.

1 Second-layer version (version)
2 Alignment mark 3 Print target printed on the first layer (true print target)
3A Temporary printing target 4 Alignment mark 7 Plate table 7a Alignment stage (alignment stage for plate)
8 Print target table 8a Alignment stage (Alignment stage for print target)
9 Blanket roll 12 High resolution alignment camera (alignment camera)
12a Field of view 13 Wide-field alignment camera 13a Field of view 15 Controller 16 Target position P1 First layer printing pattern (printing pattern)
P2 Second layer printing pattern (printing pattern)

Claims (3)

  With the alignment stage for the printing object holding the temporary printing object having the same thickness dimension as the true printing object and not having the alignment mark, the plate alignment is performed with respect to the temporary printing object. Print the printing pattern and alignment mark on the plate held on the stage via a blanket roll, and then check whether the position of the alignment mark printed on the temporary printing object is within the field of view of the alignment camera. If the position is not within the field of view, the alignment for correcting the position of the temporary print target is adjusted by the alignment stage for the print target so that the position of the alignment mark of the temporary print target is within the field of view of the alignment camera. In addition to performing the operation, the alignment stage for the printing object is added to the alignment stage for the plate. If the position of the alignment mark of the provisional print target is within the field of view of the alignment camera, the provisional print object within the field of view of the alignment camera is then performed. The position of the alignment mark is set as the target position, and then the true print target including the alignment mark corresponding to the alignment mark of the plate is held in advance on the alignment stage for the print target, and then the printing is performed. Alignment for correcting the position of the true print target is performed by the target alignment stage so that the position of the alignment mark of the true print target matches the target position, and then the plate for the plate after the alignment operation is performed. A plate held on the alignment stage; Using serial printed after alignment on the alignment stage for printed, the position correcting method for a printing apparatus, characterized in that to perform the offset printing through the blanket roll.   The printing pattern and the alignment mark of the above plate are printed by bringing the blanket roll into contact with the printing plate held on the printing plate alignment stage and the printing target holding the printing target alignment stage sequentially from above. In the offset printing apparatus that can perform the offset printing process, an alignment mark having the same thickness dimension as that of the true print object to be held on the alignment stage for the print object instead of the true print object is provided. A temporary printing object that is not printed, an alignment mark that is provided in advance on the true printing object that is held on the alignment stage for the printing object, and an alignment mark that is printed from the plate on the temporary printing object are detected. Alignment camera for detection and detection by the above alignment camera And a controller for giving a command to the alignment stage for the printing target and the alignment stage for the plate based on the information on the position of the alignment mark in the true printing target and the temporary printing target. A position correction device for a printing apparatus.   The controller determines whether or not the alignment mark printed from the plate on the temporary printing target is within the field of view of the alignment camera when the temporary printing target is held on the alignment stage for the printing target. And when it is determined that the alignment mark on the temporary print target is not within the field of view of the alignment camera, the alignment mark for the temporary print target After performing the alignment operation of the alignment stage, the function for causing the alignment stage for the plate to perform the alignment operation similar to the alignment operation of the alignment stage for the printing target, and the alignment mark on the temporary printing target within the field of view of the alignment camera If it is determined that there is In the state where the true print target is held on the alignment stage for the print target, the true print target detected by the alignment camera is set. The position correction apparatus for a printing apparatus according to claim 2, wherein the position of the alignment mark provided in advance performs a function of performing an alignment operation on the alignment stage for printing so as to coincide with the target position.

Images