JP7084241B2 - Distortion correction method and distortion correction device - Google Patents

Description

In the present invention, an ink image corresponding to the above image data is received by a blanket using an intaglio for printing manufactured based on the image data, and then the blanket is pressed while being deformed according to the curved surface of the container to press the ink image. It relates to a distortion correction technique for correcting distortion generated when transferring to a curved surface and printing.

Intaglio printing has the characteristic that the pattern engraved on the intaglio can be printed with higher reproducibility than printing methods such as screen printing and inkjet. Attempts have been made to utilize this characteristic to perform intaglio printing on articles (for example, bottles, in-vehicle parts, etc.) that have been subjected to three-dimensional processing having a curved surface (Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-132052

In this printing device, in order to enable printing that follows the curved surface of the article, a blanket having flexibility that can follow the shape of the article is used. More specifically, after receiving the ink image corresponding to the image data on the blanket using the intaglio for printing manufactured based on the image data, the blanket is pressed while being deformed according to the curved surface of the article to press the ink image on the curved surface. Transfer to and print.

However, the printed image transferred to the article may be distorted due to the deformation of the blanket, and may be different from the image originally intended to be printed, that is, the image corresponding to the image data.

The present invention has been made in view of the above problems, and is good at correcting distortions generated when printing an image using a printing intaglio on an article having a three-dimensional curved surface such as a bottle or an in-vehicle part. It is an object of the present invention to provide a distortion correction method and a distortion correction device that enable various printing.

One aspect of the present invention is to use a printing recess and ink manufactured based on the image data to allow the blanket to receive an ink image corresponding to the image data, and then press the blanket while deforming it according to the curved surface of the container. This is a distortion correction method that corrects image distortion that occurs when an image corresponding to image data is printed by transferring the ink image to a curved surface, and corresponds to the measurement pattern using a concave plate for measurement that has a measurement pattern. The first step of accepting the pattern image on the blanket and the second step of transferring the pattern image to the film by pressing the blanket that received the pattern image while deforming it according to the curved surface of the container through the film, and the pattern image The third step of acquiring the amount of distortion by comparing the film image obtained by imaging the transferred film in a plane-developed state with the measurement pattern, and the corrected image data obtained by correcting the image data according to the amount of distortion. It is characterized by including a fourth step of creating a concave plate for printing based on the above.

Another aspect of the present invention is to use a printing recess and ink manufactured based on the image data to allow the blanket to receive an ink image corresponding to the image data, and then push the blanket while deforming it according to the curved surface of the container. It is a distortion correction device that corrects the distortion of the image that occurs when the image corresponding to the image data is printed by applying the ink image to a curved surface, and is a pattern that acquires information about the measurement pattern provided in the concave plate for measurement. After receiving the pattern image corresponding to the measurement pattern on the blanket using the information acquisition unit and the concave plate for measurement, the pattern image is transferred by pressing the blanket through the film while deforming it according to the curved surface of the container. Further, a film image acquisition unit that acquires a film image obtained by developing a film in a plane and taking an image, a strain amount acquisition unit that acquires a distortion amount by comparing a measurement pattern with a film image, and a concave plate for printing are manufactured. It is characterized in that it is provided with a data correction unit that corrects image data according to the amount of distortion.

In the invention configured in this way, the following operations are performed before manufacturing the intaglio for printing. That is, the pattern image is received on the blanket using the intaglio for measurement. Then, the blanket is pressed through the film while being deformed according to the curved surface of the container, and the pattern image is transferred onto the film. After this film is developed in a plane, it is imaged and a film image is acquired. Further, the amount of distortion is calculated by comparing the pattern image included in the film image with the measurement pattern. Further, the image data is corrected by the amount of distortion.

As described above, since the amount of distortion is acquired before the intaglio for printing is manufactured and the image data is corrected by the amount of distortion, the image is printed using the intaglio for printing on an article having a curved surface having a three-dimensional shape. Distortion that occurs at the time of printing is corrected, and good printing is possible.

It is a printing system equipped with one embodiment of the distortion correction device according to the present invention. It is a figure which shows typically the structure of the printing apparatus installed in the printing system shown in FIG. 1. It is a figure which shows typically the structure of the holder for holding a container. It is a flowchart which shows the operation of the printing system shown in FIG. It is a flowchart which shows the distortion correction process in FIG. It is a figure which shows typically the procedure of deriving the correction information. It is a figure which shows typically the printing procedure to the container using the correction information.

FIG. 1 is a printing system equipped with an embodiment of a distortion correction device according to the present invention, and a cylinder of a container B such as a beverage glass bottle or a cosmetic glass bottle, which is an example of the “article” of the present invention, using a printing recess. A desired image is printed on the portion Ba with an ultraviolet curable ink (hereinafter, simply referred to as “ink”). Image data 11 such as characters, logos, patterns, and illustrations to be printed on the container B by the printing system 100 are edited in advance by the server 1 and stored in the server storage unit (not shown). The printing system 100 is provided with a plate making device 2 and a printing device 3. Of these, the plate making device 2 prints an uneven pattern corresponding to an image to be printed on the container B (for example, the rose image at the left end of FIG. 7) based on the image data 11 given by the server 1 intaglio for printing (FIGS. 2 and 6). It is formed in the code PP) inside. On the other hand, the printing device 3 prints the image corresponding to the image data 11 on the body Ba of the container B by using the printing intaglio manufactured by the plate making device 2.

FIG. 2 is a diagram schematically showing the configuration of a printing apparatus. The printing device 3 has a housing 31 having a top plate, a side wall surface, and a bottom plate, a base 32 provided inside the housing 31, and is extended in the left-right direction of FIG. 2 on the upper portion of the base 32 in the paper surface direction. It has two guide rails 33 provided apart from each other. The guide rail 33 (guide rail shown in FIG. 2) on the front side in the direction of the paper surface has a first groove portion (not shown) and a first ball screw (not shown). Further, the guide rail 33 on the back side in the paper surface direction (the guide rail (not shown) located on the back side of the guide rail 33 shown in FIG. 1) has a second groove portion (not shown) and a second ball screw (not shown). Have.

In the printing apparatus 3, the plate stage 34 is provided so as to be fitted to the first groove portion of the guide rail 33 on the front side in the paper surface direction and connected to the first ball screw, and the intaglio PP for printing is provided on the upper surface of the plate stage 34. It is possible to fix the intaglio MP for measurement, which will be explained later. Therefore, the plate stage 34 moves along the first groove portion of the guide rail 33 while holding the intaglio PP for printing by the rotational drive of the first ball screw, and the blanket cylinder 35 and the doctor blade (not shown) that support the blanket 351. Move back and forth with respect to (omitted). In this way, while the printing intaglio PP reciprocates together with the plate stage 34, ink is supplied to the upper surface of the printing intaglio PP, and the ink is filled in the recesses formed in the printing intaglio PP by the doctor blade to form an ink image. The ink image is received from the intaglio PP for forming and printing to the blanket 351. The blanket 351 is made of a soft material having a hardness lower than that of the container B such as silicon rubber.

Further, a holder 36 is provided so as to be fitted to the second groove portion of the guide rail 33 on the back side in the paper surface direction of FIG. 2 and connected to the second ball screw, and the container B can be rotatably held by the holder 36. It has become. Therefore, the holder 36 moves along the second groove portion of the guide rail 33 while holding the container B by the rotational drive of the second ball screw, and is rotatably fixed at a predetermined position by the support column 352 to the blanket body 35. The holder 36 is positioned with respect to the holder 36. More specifically, the holder 36 is positioned so as to be pressed against the blanket 351 while being deformed according to the body portion Ba of the container B.

FIG. 3 is a diagram schematically showing the configuration of a holder for holding a container. As shown in the figure, the holder 36 has a base portion 21. The base portion 361 is connected to the second ball screw. Further, two pillar portions 362 and 363 are erected from the upper surface of the base portion 361. The pillar portions 362 and 363 are provided so as to face each other with a distance slightly longer than the height of the container B (the length from the bottom to the container mouth). Although not shown, the pillars 362 and 363 are provided with through holes in the height direction of the container B (left-right direction in the figure), respectively. These through holes are arranged in a row along the height direction. The bottom holding portion 364 is provided in the through hole provided in the pillar portion 362, while the lid closing holding portion 365 is provided in the through hole provided in the pillar portion 363.

The bottom holding portion 364 has a rotating body 364a rotatably provided with respect to the pillar portion 362, and a spring member 364b attached to the rotating body 364a. One end of the spring member 364b is a fixed end fixed to the rotating body 364a, and the other end is a free end extending toward the column 363. On the other hand, the lid closing holding portion 365 has a connecting member 365a that is rotatably supported by the pillar portion 363 and is detachably attached to the lid closing portion Bc. Therefore, as shown in FIG. 3, the bottom portion Bb of the container B is pressed against the other end portion of the spring member 364b against the urging force of the spring member 364b, and the container B is placed between the pillar portions 362 and 363 in a horizontal state. Can be placed. Further, by connecting the lid closing portion Bc of the container B to the connecting member 365a of the lid closing holding portion 365, the container B rotates in a state of being sandwiched between the rotating body 364a and the connecting member 365a by the urging force of the spring member 364b. It is rotatably held around the axis AX. The lid closing portion Bc means a portion of the upper end range from the shoulder portion of the body portion Ba to the container mouth to which the lid of the container B (not shown) is attached. A container opening is opened at the upper end (right side in FIG. 3) of the lid closing portion Bc, and a male screw (not shown) is appropriately formed from near the container opening toward the body portion Ba. In addition to the continuous spiral male screw, the male screw has a shape such as being partially cut as appropriate.

With the holder 36 configured in this way, the container B can be attached and detached by the operator. That is, after the container B is placed between the pillars 362 and 363 in a horizontal state while pressing the bottom Bb of the container B before printing against the spring member 364b, the lid closing portion Bc of the container B is connected to the lid closing holding portion 365. The container B can be attached to the holder 36 by connecting to the member 365a. Further, after printing, the container B printed on the holder 36 is moved to the pillar portion 362 side while resisting the urging force of the spring member 364b, and the connection of the lid closing portion Bc by the connecting member 365a is released to connect the container B. It can be removed from the holder 36. The method for attaching / detaching the container B to / from the holder 36 is not limited to this, and an attachment / detachment method according to the holding function of the container B in the holder 36 can be adopted.

The holder 36 has a rotation function of rotating the container B around the rotation axis AX during intaglio printing by the printing device 3, in addition to the holding function of simply holding the container B rotatably in a horizontal state. This rotation function is performed by the container rotation unit 26. The container rotating portion 366 has a rotating motor 366a and a rotation transmitting mechanism 366b that transmits the rotational force of the motor 366a to the lid closing portion Bc of the container B. By the operation of the motor 366a, the container B before printing is sandwiched between the bottom holding portion 364 and the lid closing holding portion 365, and is held in a horizontal posture by rotating around the rotation shaft AX to execute the transfer process.

More specifically, as shown in FIG. 2, the blanket cylinder 35 is formed by a drive unit (not shown) in a state where the container B is pressed against the blanket 351 and the blanket 351 is deformed in accordance with the body portion Ba of the container B. The ink image carried on the blanket 351 is transferred to the container B by rotating the container B counterclockwise in the figure by rotating the container B in the counterclockwise direction. Further, the transferred ink image is cured by the ultraviolet rays emitted from the ultraviolet irradiation unit (not shown) and fixed in the container B, and the image corresponding to the image data 11 is printed on the container B.

In such a printing mode, since the soft blanket 351 is deformed during the transfer process, the image printed on the container B may be distorted and may be different from the image originally intended to be printed, that is, the image corresponding to the image data 11. .. Therefore, in the present embodiment, as will be described in detail later, the amount of distortion and the correction information for eliminating the image distortion are calculated by using the film and the intaglio MP for measurement for printing the measurement pattern. The image data 11 is corrected based on the correction information.

Therefore, in the present embodiment, a scanner 4 that captures an image of a film on which a pattern image corresponding to a measurement pattern is printed and a distortion correction device 5 that performs distortion correction processing are provided. Of these, as the scanner 4, for example, a conventionally known flatbed type image reader or the like can be used. Further, the distortion correction device 5 is composed of a computer having a CPU (= Central Processing Unit), a RAM (= Random Access Memory), etc., and has four functional block units, that is, an intaglio MP for measurement, as described below. The pattern information acquisition unit 51 that acquires information about the measurement pattern provided in
A film image acquisition unit that acquires a film image obtained by developing a film F (see (b) in FIG. 6) on which a pattern image corresponding to a measurement pattern is printed using an intaglio MP for measurement and imaging it with a scanner 4. 52 and
A strain amount acquisition unit 53 for acquiring a strain amount by comparing a measurement pattern with a pattern image included in a film image,
It has a data correction unit 54 that corrects the image data 11 according to the amount of distortion.

Next, refer to FIGS. 4 to 7 for the operation of printing the image corresponding to the image data 11 (for example, the rose image at the left end in FIG. 7) on the container B by the printing system 100 configured as described above. I will explain while.

FIG. 4 is a flowchart showing the operation of the printing system shown in FIG. 1, and FIG. 5 is a flowchart showing the distortion correction process in FIG. Further, FIG. 6 is a diagram schematically showing a procedure for deriving the correction information, and FIG. 7 is a diagram schematically showing a procedure for printing on a container using the correction information. In the present embodiment, as shown in FIG. 4, the distortion correction process (step S1) is executed before the intaglio PP for printing is manufactured based on the image data 11. Then, instead of manufacturing the intaglio PP for printing by using the image data 11 given from the server 1 as it is, the intaglio PP for printing is based on the image data 11 obtained by correcting the image data 11 by the distortion correction process. Is being manufactured (step S2). Then, an image (printed image in FIG. 7) is printed on the container B using the distortion-corrected printing intaglio PP produced in this way. That is, the feature of this embodiment is that the CPU of the distortion correction device 5 controls each part of the device according to the distortion correction program stored in advance in the storage unit (not shown) to perform the distortion correction process (step S1) as follows. It is in the point of running.

In this distortion correction process, the intaglio MP for measurement provided by dispersing the grid points MPa having a concave shape on the entire surface is placed on the plate stage 34 by an operator or a transfer robot and fixed (step S11). The dispersion mode of the grid points MPa is arbitrary, but in (a) in FIG. 6, they are arranged in a two-dimensional matrix-like measurement pattern. The vertical and horizontal lines in (a) in the figure are virtual lines provided to facilitate recognition of the arrangement state of the grid points MPa, and are not included in the measurement pattern. Of course, a vertical line and / or a horizontal line may be provided as a measurement pattern together with the grid point MPa.

Then, the printing process is performed in the same manner as the so-called normal printing operation in which the image is printed on the container B using the intaglio PP for printing and the ink, except that the printing target is the film F (see (b) in FIG. 6). (Steps S12 to S14). That is, while the intaglio MP for measurement reciprocates together with the plate stage 34, ink is supplied to the upper surface of the intaglio MP for measurement, and the ink is formed in the intaglio MP for measurement by a doctor blade (not shown), that is, The dot pattern image is formed by filling the lattice points MPa (step S12), and the dot pattern image is received from the intaglio MP for measurement to the blanket 351 (step S13).

On the other hand, by the time the receiving operation is completed, the container B in which the film F is tightly wound around the body portion Ba is prepared by the operator and set in the holder 36. Then, after receiving the dot pattern image, the container B with a film moves toward the blanket body 35 together with the holder 36 and is pressed against the blanket 351. As a result, the blanket 351 is deformed following the body portion Ba of the container B. In this way, the nip region is formed with the film F interposed between the blanket 351 and the container B. Then, the blanket body 35 rotates counterclockwise in FIG. 2 and the container B rotates clockwise in FIG. 2 while the nip region is formed. Then, when the container B makes one rotation around the rotation axis AX, the dot pattern image received by the blanket 351 is transferred to the film F (step S14). At this time, for example, as shown in FIG. 6B, the plurality of dot DTs constituting the dot pattern image are displaced from the coordinates of the grid point MPa due to the influence of the distortion caused by the deformation of the blanket 351. In addition, in (b) of the figure, a vertical line and a horizontal line are shown in addition to the dot DT, but these are virtual lines provided to make it easier to recognize the arrangement state of the dot DT, and are dot pattern images. Not included in.

When the printing of the dot pattern image on the film F is completed in this way, the operator removes the container B with the film from the holder 36, and further removes the film F on which the dot pattern is printed from the container B. The film F is unfolded in a plane and placed on a flat bed (not shown) of the scanner 4. Then, the dot pattern image printed on the film F is read, and the read image including the dot pattern image is given to the distortion correction device 5 (step S15).

The distortion correction device 5 calculates the amount of distortion by comparing the measurement pattern of the intaglio MP for measurement (several grid points MPa) with the printed dot pattern image (dot DT of the same number as the grid points MPa) (step). S16). More specifically, the change in the coordinate position between the grid point MPa and the corresponding dot DT is calculated as the strain amount for each grid point MPa (step S16). Then, the correction amount for canceling the plurality of strain amounts thus obtained (corresponding to the arrow in (c) of FIG. 6) is calculated as the correction information when printing on the container B (step S17). Further, as shown in FIG. 7, the image data 11 stored in the server 1 for manufacturing the intaglio PP for printing is corrected by the correction information (step S18). The image data 11 corrected in this way is returned to the server 1, and the correction update of the image data 11 is performed. Then, the intaglio PP for printing is manufactured according to the image data 11 corrected as described above, and the intaglio printing on the container B is executed using the intaglio PP for printing.

As described above, in the present embodiment, the strain correction process (steps S11 to S18) is executed before the intaglio PP for printing is manufactured to manufacture the intaglio PP for printing suitable for intaglio printing on the container B. .. Since the image is printed on the container B using the corrected intaglio PP for printing, the desired image can be printed well on the container B without being affected by the distortion caused by the deformation of the blanket 351. Can be done.

As described above, in the above embodiment, the body portion Ba of the container B corresponds to an example of the “curved surface of the container” of the present invention. Further, as shown in FIG. 6B, a plurality of dot DTs printed on the film F correspond to an example of the "pattern image corresponding to the measurement pattern" of the present invention. Further, the corrected image data 11 shown in FIG. 7 corresponds to an example of the “corrected image data” of the present invention. Further, steps S13 and S14 in FIG. 5 correspond to the "first step" and the "second step" of the present invention, respectively. Further, steps S15 and S16 in FIG. 5 correspond to the "third step" of the present invention, and steps S17 and S18 in FIG. 5 correspond to the "fourth step" of the present invention.

The present invention is not limited to the above-described embodiment, and various modifications can be made other than those described above as long as the present invention is not deviated from the gist thereof. For example, in the above embodiment, the distortion correction process (step S1) is performed using the same ink as the ink used for the container B, but different inks may be used. Further, inks other than the ultraviolet curable ink may be used for both printing and measurement.

Further, in the above embodiment, the film F is brought into close contact with the container B in advance to perform the strain correction process (step S1), but the container B and the blanket 351 are pressed against each other in the nip region formed by the container B and the blanket 351. A dot pattern image may be printed on the film F by feeding the film F in synchronization with the rotation of the blanket 351. The type of the film F is arbitrary, and a PET film (a polymer film made of polyethylene terephthalate resin), a shrink film, or the like can be used.

Further, in the above embodiment, a scanner 4 other than the flatbed type may be used to read the pattern image printed on the film F.

Further, in the above embodiment, the container B is exemplified as an article to be printed, but the "article" of the present invention is not limited to this, and an article having a three-dimensional curved surface such as an in-vehicle part can be used. Includes.

Further, in the above embodiment, all the functional block units of the distortion correction device 5, that is, the pattern information acquisition unit 51, the film image acquisition unit 52, the distortion amount acquisition unit 53, and the data correction unit 54 are combined with the server 1, the plate making device 2, and printing. Although it is provided independently from the device 3 and the scanner 4, a part or all of them may be incorporated in each part. For example, a data correction unit 54 is incorporated in the plate making device 2, and image data 11 is acquired from the server 1 and is distorted. It may be configured to acquire correction information from the correction device 5. In this case, various data necessary for manufacturing the intaglio PP for printing can be created based on the image data 11 and the correction information without waiting for the correction update of the image data 11, and the processing speed can be improved.

In the present invention, an ink image corresponding to the above image data is received by a blanket using an intaglio for printing manufactured based on the image data, and then the blanket is pressed while being deformed according to a curved surface of a container to be pressed against the ink image. It can be applied to all distortion correction techniques that correct the distortion that occurs when printing is performed by transferring the ink to a curved surface.

5 ... Distortion correction device 11 ... Image data 51 ... Pattern information acquisition unit 52 ... Film image acquisition unit 53 ... Distortion amount acquisition unit 54 ... Data correction unit 351 ... Blanket B ... Container (article)
Ba ... Body (curved surface)
F ... Film MP ... Intaglio for measurement PP ... Intaglio for printing

Claims (4)

After receiving the ink image corresponding to the image data on the blanket using the printing recess and ink manufactured based on the image data, the blanket is pressed while being deformed according to the curved surface of the container to press the ink image. It is a distortion correction method for correcting the distortion of the image generated when the image is transferred to the curved surface and the image corresponding to the image data is printed.
The first step of causing the blanket to receive a pattern image corresponding to the measurement pattern using a measurement intaglio having a measurement pattern, and
The second step of transferring the pattern image to the film by pressing the blanket that has received the pattern image through the film while deforming it according to the curved surface of the container.
The third step of obtaining the amount of distortion by comparing the film image obtained by imaging the film on which the pattern image is transferred in a plane-developed state with the measurement pattern.
A distortion correction method comprising a fourth step of creating the printing intaglio based on the corrected image data obtained by correcting the image data according to the distortion amount. The distortion correction method according to claim 1.
The measurement pattern is composed of a plurality of grid points provided dispersedly from each other.
The pattern image is composed of dots printed on the film corresponding to each grid point.
The third step is a strain correction method for calculating the deviation between the coordinate position of the grid point on the measuring concave plate and the coordinate position of the dot on the film image as the strain amount for each grid point. .. The distortion correction method according to claim 1 or 2.
The first step is a distortion correction method which is a step of forming the pattern image with the ink. After receiving the ink image corresponding to the image data on the blanket using the printing recess and ink manufactured based on the image data, the blanket is pressed while being deformed according to the curved surface of the container to press the ink image. It is a distortion correction device that corrects the distortion of the image generated when the image is transferred to the curved surface and the image corresponding to the image data is printed.
A pattern information acquisition unit that acquires information about measurement patterns provided in the intaglio for measurement, and a pattern information acquisition unit.
The pattern image corresponding to the measurement pattern is received by the blanket using the concave plate for measurement, and then the blanket is pressed through the film while being deformed according to the curved surface of the container to obtain the pattern image. A film image acquisition unit that acquires a film image obtained by developing the transferred film in a plane and taking an image.
A strain amount acquisition unit that acquires a strain amount by comparing the measurement pattern with the film image,
A distortion correction device including a data correction unit that corrects the image data according to the amount of distortion before manufacturing the intaglio for printing.

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