Method for producing sheet-like member

Abstract

To provide a method for producing a sheet-like member that enables clear in-line detection of differences in the uneven state of uneven portions imparted to a sheet to be processed.SOLUTION: A method for producing a sheet-like member with an uneven portion formed by processing includes a processing step of forming uneven portions on a sheet to be processed, and an inspection step of determining the uneven state of the processed uneven portions. The inspection step includes: an illumination step of sequentially irradiating the uneven portions with a plurality of light patterns from an oblique direction relative to the sheet to be processed; an imaging step of capturing images of the uneven portions at timings relatively when the plurality of light patterns is emitted to generate images corresponding to the plurality of light patterns; a first inspection image generation step of generating a surface shape image indicating a surface shape of the sheet to be processed based on the plurality of images obtained in the imaging step; an uneven portion measurement step of calculating image measurement values of the uneven portions; and a determination step of determining acceptability of the uneven state of the uneven portions by comparing the image measurement values of the uneven portions with preset threshold values.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a method for producing a sheet-like member. [Background technology]

[0002] Conventionally, several techniques have been proposed for determining whether processing is good or bad in a manufacturing process.

[0003] For example, Patent Document 1 describes a method for manufacturing a sheet-like member, which involves forming a coating layer of a hot melt adhesive or a functional agent on a substrate sheet and judging the quality of the coating layer. In this process, multiple patterned lights are irradiated from an oblique direction, an image is captured from a different oblique direction, and a specular reflection component is extracted from the captured image to generate an inspection image. The quality judgment is based on this. This can be said to take advantage of the fact that the coating layer and the substrate sheet are made of different materials and have different light reflectances, resulting in a difference in the specular reflection component.

[0004] Patent Document 2 describes a method for inspecting components of absorbent articles or semi-finished absorbent articles during transportation. In this method, light is illuminated from multiple directions at different times, and images are captured for each illumination at different times, which are then combined to determine whether the components are good or bad. The method uses image multiplication and addition for the combination. A specific example of this method is a method for inspecting fastening tape for diapers. Positional data on the fastening tape is used to determine whether the attachment position is appropriate. Furthermore, the presence of wrinkles, folds, etc., exceeding a certain area and volume is determined based on whether the pixel values ​​of the fastening tape are within a certain range. Patent Document 3 describes a method for predicting the occurrence of liquid leakage from the horizontal heat-sealed portion of a filled package made of a metal foil laminated film. To form the horizontal heat-sealed portion, a horizontal seal blade on a horizontal seal roll is used that has a measurement groove running across its entire width. When a tubular packaging film is sandwiched between a pair of horizontal seal rolls to form a horizontal seal, a measurement protrusion is formed at a position corresponding to the measurement groove. The prediction method identifies the distortion of this measurement protrusion to predict the occurrence of liquid leakage due to wrinkles or bubbles in the horizontal seal. The distortion is identified by irradiating the upper corner of the measurement protrusion from diagonally above and comparing the length of the shadow formed with a reference value.

[0005] Patent Document 4 describes a method for detecting defective seals on medicine packages. The seal is configured by forming a mesh-like thermal seal groove of a predetermined depth in the seal area where a synthetic resin sheet and an aluminum packaging film are thermally bonded. In this method, light is irradiated onto the seal groove, and the reflected light is captured by a screen. The defective seal is detected based on the amount of incident light (brightness or darkness of the screen). If there is a defective seal, a seal groove of the predetermined depth is not formed, so diffuse reflection does not occur and the amount of incident light on the screen increases. If the amount of light incident on the light receiver from this screen exceeds a predetermined value, it is determined that a defective seal has occurred. That is, if the amount of incident light, which is an inspection indicator, is appropriately reduced, it is determined that the seal is good, and if the incident light is excessively increased, it is determined that the seal is defective. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2022-042521 [Patent Document 2] Patent Publication No. 2021-122578 [Patent Document 3] Japanese Patent Application Publication No. 2020-169061 [Patent Document 4] Special Publication No. 7-40001 Summary of the Invention [Problem to be solved by the invention]

[0007] In a manufacturing method for forming a sheet-like member by imparting a concave-convex portion to a processing target sheet, the quality of the concave-convex state has conventionally been determined by offline inspection, and defective products are discarded and non-defective products are selected. In terms of production efficiency, however, it is required to perform the above-mentioned inspection inline. It is preferable that the inline inspection can be performed on the sheet-like member in either a continuous state or a sheet state. However, the unevenness varies in shape and pattern, size of the convex and concave portions, height of the convex portions, and depth of the concave portions. Furthermore, the unevenness is often very fine. It has been difficult to clearly distinguish adjacent unevennesses in-line and accurately grasp their contours in order to grasp the unevenness state of such unevenness. Therefore, there is room for improvement in clearly grasping the difference in unevenness state in line according to the shape and size of the unevenness. In this regard, since the uneven portions are formed on a processing target sheet of the same material, in the inspection described in Patent Document 1, the difference in the specular reflection component between the convex and concave portions is small, and differences in shading are unlikely to occur on the image. In particular, when the reference uneven portion is minute (the difference in height between the concave and convex portions is small, and the area of ​​the concave and convex portions in the planar direction is small), the differences in shading are likely to be even smaller. Therefore, image judgment based on the specular reflection component is difficult to use to grasp the uneven state. Furthermore, Patent Documents 2 to 4 do not disclose any technology for grasping the uneven state of minute uneven portions.

[0008] In view of the above, the present invention relates to a method for manufacturing a sheet-like member that enables the difference in the uneven state of the uneven portion imparted to the sheet to be processed to be clearly captured in-line, thereby increasing inspection accuracy and improving manufacturing stability in the manufacturing method. [Means for solving the problem]

[0009] The present invention provides a method for producing a sheet-like member having an uneven portion formed by processing, comprising the steps of: a first inspection image generation step of extracting and combining components indicative of the uneven state from the plurality of images acquired in the imaging step in accordance with the size of the uneven portion to generate a surface shape image showing the shape of the surface of the sheet to be processed; ...

[0010] The present invention also provides a manufacturing device for a sheet-like member having a concave-convex portion formed by processing, the manufacturing device including a processing device that forms the concave-convex portion on a processing target sheet, and an inspection device that determines the concave-convex state of the processed concave-convex portion on the surface of the processing target sheet, the inspection device including an illumination device that sequentially irradiates the concave-convex portion with a plurality of pattern lights from a direction oblique to a line perpendicular to the surface of the processing target sheet, an imaging device that images the concave-convex portion at the timing when the plurality of pattern lights are irradiated and generates a plurality of images corresponding to the plurality of pattern lights, and a plurality of images acquired by the imaging device. and an image processing device based on a plurality of images acquired by the imaging device, the image processing device including a first inspection image generation unit that extracts and combines components that indicate the uneven state according to the size of the uneven portion from the plurality of images acquired by the imaging device to generate a surface shape image that indicates the shape of the surface of the sheet to be processed; an uneven portion measurement unit that sets at least one inspection area for the uneven portion in the surface shape image and calculates image measurement values ​​of the uneven portion; and a judgment unit that compares the image measurement values ​​of the uneven portion with a predetermined threshold value to judge whether the uneven state of the uneven portion is good or bad. [Effects of the Invention]

[0011] According to the sheet-like member manufacturing method of the present invention, it is possible to clearly detect the difference in the unevenness of the uneven portion imparted to the processing target sheet in-line, thereby improving the inspection accuracy and improving the manufacturing stability of the manufacturing method. This makes it possible to accurately identify good products and reliably reject defective products. According to the sheet-like member manufacturing apparatus of the present invention, the sheet-like member manufacturing method of the present invention can be suitably implemented. [Brief explanation of the drawings]

[0012] [Figure 1] (A) is a plan view schematically showing a continuous sheet of packaging material before it is separated into sheets, relating to a manufacturing method of a sheet-like packaging material containing a packaged item as an example of a manufacturing method of a sheet-like member according to the present invention, and (B) is a partially enlarged plan view of the uneven portion (seal portion) formed on the outer periphery of the packaged item of the packaging material. [Figure 2] (A) is an explanatory diagram showing the process of forming an uneven portion by embossing from the top sheet side in relation to a method for manufacturing an absorbent article as an example of a method for manufacturing a sheet-like member according to the present invention, (B) shows a state in which the indentation depth of the uneven portion (embossed portion) is appropriate (a good product), and (C) shows a state in which the indentation depth of the uneven portion is insufficient (a defective product). [Figure 3] As an example of an imaging process in the method for manufacturing a sheet-like member according to the present invention, (A) shows an imaging process for the uneven portion shown in Figure 2(B), and (B) shows an imaging process for the uneven portion shown in Figure 2(C). [Figure 4] 1 is a diagram showing an example of a manufacturing apparatus used in a method for manufacturing a sheet-like package containing an item to be packaged, as an example of a method for manufacturing a sheet-like member according to the present invention. [Figure 5] (A) is a schematic diagram showing an example of multiple pattern lights in the illumination process, (B) is a schematic diagram showing an example of multiple images (original images) obtained in the imaging process under (A), and (C) is a drawing substitute diagram showing an example of a surface shape image obtained by the first inspection image generation process. [Figure 6] FIG. 1 is a configuration diagram schematically illustrating an example of an image processing device. [Figure 7] (A) is a drawing substitute photograph showing an example of a surface shape image (example of the present invention) obtained when the feature size, one of the generation conditions in the first inspection image generation process, is set to 15; (B) is a drawing substitute photograph showing a specular reflection image (comparison example) in which the specular reflection component has been extracted and synthesized; and (C) is a drawing substitute photograph showing a surface shape image (comparison example) synthesized when the feature size, one of the generation conditions in the first inspection image generation process, is changed to 4. [Figure 8] 2 is an explanatory diagram schematically illustrating an example of an imaging area in the continuum of packaging materials shown in FIG. 1 and an inspection area in an image captured in the imaging area. FIG. [Figure 9] 10 is a graph showing an example of the correlation between the black area value and the seal strength for images of two horizontal seal portions (concave and convex portions) in a surface shape image of a continuum of packaging materials. [Figure 10] (A) and (B) are photographs in lieu of drawings showing two types of surface shape images (examples of the present invention) with different seal strengths obtained by the illumination process, imaging process, and first inspection image generation process in the manufacturing method for sheet-like members according to the present invention; (C) is a graph showing a comparison of the black area values ​​obtained by the unevenness measurement process for the surface shape images of (A) and (B); and (D) to (E) are graphs showing a comparison of the black area values ​​and photographs in lieu of drawings showing images of two types of seal strengths (comparative examples) obtained by full-surface lighting. [Figure 11] 10 is a table showing the relationship between the angle θc of the imaging device, the angle θL of the lighting device, and the black area value [pixels]. [Figure 12] In addition to (A) and (B) shown in FIG. 5, (C) and (D) are representative photographs showing examples of a surface shape image and an average image generated from multiple images obtained in the imaging process, and (E) is a substitute photograph showing an example of a calculated image obtained by calculating the surface shape image and the average image. [Figure 13] 10 is a flowchart showing an example of a method for manufacturing a sheet member according to the present invention, including generation of a surface shape image, an average image, and a calculated image. [Figure 14] 10(A) to 10(G) are explanatory diagrams showing an example of an inspection image calculation step. [Figure 15] FIG. 5 is a configuration diagram showing an example of a manufacturing apparatus different from the manufacturing apparatus shown in FIG. [Figure 16] 10(A) to 10(C) are plan views showing examples of patterns of the concave and convex portions. DETAILED DESCRIPTION OF THE INVENTION

[0013] The method for producing a sheet-like member of the present invention will be described below with reference to the drawings. In the method for producing a sheet-like member of the present invention, the sheet to be processed can be made of various materials that can be processed to form uneven portions, including, for example, resin films, nonwoven fabrics, paper, and metal films. The types of processing for the processing target sheet can include various types, such as sealing, embossing, uneven shaping using an uneven gear roll, etc. The sealing and embossing can be performed by commonly used methods such as heat sealing and ultrasonic sealing. The surface to be inspected in the processing target sheet may be a surface on which recesses are formed by processing, or a surface on which protrusions are formed. In the latter case, for example, the surface opposite to the surface on which recesses are formed by processing may be the surface to be inspected. The processing target sheet is not limited to one sheet, and may be multiple sheets. When there are multiple processing target sheets, in the processing step, all of the multiple stacked sheets may be processed to have projections and recesses, or only some of the multiple stacked sheets may be processed to have projections and recesses. Alternatively, after forming the uneven portion on the processing target sheet, another sheet or member may be laminated on it. In this case, the inspection process may be carried out between processing and lamination, or after processing and lamination. For example, as with the stretchable three-dimensionally shaped sheet described in paragraphs

[0026] to

[0040] of JP 2005-319730 A, after forming the uneven portion on the processing target sheet (first layer), another member (elastic strand) and another sheet (second layer) may be laminated and integrated, and then the inspection process may be carried out on the surface of the processing target sheet (first layer). Furthermore, the sheet-like member obtained by processing or the like may be incorporated into a product and then the inspection process may be carried out.

[0014] The method for producing a sheet-like member of the present invention is a method for producing a sheet-like member having uneven portions formed by processing, and includes the following steps (I) and (II) (hereinafter simply referred to as steps (I) and (II) respectively). (I) A processing step of forming the uneven portion on the sheet to be processed. (II) An inspection step for determining the uneven state of the processed uneven portion on the surface of the processing target sheet.

[0015] The inspection step (II) includes the following steps (II-1) to (II-5) (hereinafter simply referred to as steps (II-1) to (II-5) respectively). (II-1) An illumination step of sequentially irradiating the uneven portion with a plurality of patterned lights from a direction oblique to a line perpendicular to the surface of the processing target sheet. (II-2) An imaging step of capturing an image of the uneven portion at the timing when the plurality of patterned lights are irradiated, and generating a plurality of images corresponding to the plurality of patterned lights. (II-3) A first inspection image generation process in which components indicating the uneven state are extracted and synthesized from the multiple images acquired in the imaging process according to the size of the uneven portion, to generate a surface shape image showing the shape of the surface of the sheet to be processed. (II-4) An uneven portion measuring step of setting at least one inspection area for the uneven portion in the surface shape image and calculating image measurement values ​​of the uneven portion. (II-5) A judging step of comparing the image measurement value of the uneven portion with a preset threshold value to judge whether the uneven state of the uneven portion is good or bad.

[0016] In the method for manufacturing a sheet-like member of the present invention, as described above, by capturing multiple images (original images) using multiple patterned lights and performing image processing in step (II-3), it is possible to clearly grasp the differences in the unevenness of the uneven portion on the surface of a processing target sheet made of the same material with a uniform light reflectance. That is, in the first step, the multiple patterned lights are used to obtain data on the minute unevenness of the multiple captured images. In the second step, the multiple images are subjected to image processing (extracting and combining components indicating the unevenness) according to the size of the unevenness (height difference between the concave and convex portions, and the planar area of ​​the concave and convex portions) to generate a surface shape image. By combining these steps, it is possible to clearly grasp the differences in the unevenness (differences in shading on the image). Based on this, the quality of the uneven state of the uneven portion is judged, so that it is possible to improve the inspection accuracy and the manufacturing stability in the manufacturing method.

[0017] As described above, the method for producing a sheet-like member of the present invention can be carried out with a variety of target sheets, including, for example, a covering sheet in a sheet-like package containing an article to be packaged and a topsheet in an absorbent article. In the package, as shown in Fig. 1, sheets 2, 2 covering both sides of the packaged item 1 are sealed together outside the periphery of the packaged item 1. The sealed portion includes a vertical seal portion 31 along the conveyance direction Y and a horizontal seal portion 32 along the width direction X perpendicular to the vertical seal portion. A concave-convex portion 3 is formed in this sealed portion. The pattern of the concave-convex portion 3 includes, for example, a combination of a grid seal and a solid seal bordering the grid seal. The continuum 12 is divided at the sealed portions to produce individual packages 10. Examples of qualities that determine the quality of the concave-convex portion 3 include seal strength and airtightness. Numerical values ​​indicating these qualities can be set appropriately depending on the performance and seal pattern required of the sheet-like member to be produced. The topsheet of the absorbent article may include, for example, a round embossed portion surrounding the excrement absorption area and an arched embossed portion on its widthwise side. For example, as shown in FIG. 2(A), the topsheet 5 and absorbent body 6 are indented by a sealing unit 8 (a combination of a pattern roll 82 having a plurality of patterned seal projections 81 on its circumferential surface and an anvil roll 83) to form the indented portion 7. Although not shown, the indented portion 7 may also have alternating high- and low-embossed recesses of different depths arranged along the direction in which the round embossed portions and the arched embossed portions are continuous. FIG. 2(B) shows the indented portion 7 with an appropriate indentation depth. If the indentation depth of the indented portion 7 is insufficient, the absorbent body 6 may lift, resulting in a failure to integrate the topsheet 5 and absorbent body 6 (a defective product), as shown in FIG. 2(C). The quality of the indented portion 7 can be determined by, for example, preventing twisting and leakage due to sealing with recesses of a predetermined depth, and the design of the appearance.

[0018] The difference between a good product and a defective product in the concave-convex portion as shown in FIGS. 2(B) and 2(C) is the difference in the state of the indentation (concave-convex state) of the concave-convex portion 7. The method for manufacturing a sheet member of the present invention performs image measurement (steps (II-1) to (II-5)) that utilizes differences in the state of indentations. This makes it possible to clearly capture the difference in shading on the image of the uneven state. For example, as shown in FIG. 3(A), by irradiating a plurality of patterned lights L obliquely onto an uneven portion 7 with an appropriate indentation state (appropriate depth), light L1 reflected from the recesses does not reach the imaging device 140. As a result, an image can be obtained in which the shadows of the recesses relative to the protrusions are clearly visible. On the other hand, as shown in FIG. 3(B), when a plurality of patterned lights L is irradiated onto an uneven portion 7 with an insufficient indentation state (insufficient depth) under the same conditions as above, light L1 reflected from the recesses reaches the imaging device 140. As a result, the image will show a weak or absent shadow of the recesses relative to the protrusions, making the difference in the uneven state unclear. On the image, the shaded areas corresponding to the appropriate depth of the indentation are black pixels, and the remaining areas are white pixels. By understanding the size, shape, and arrangement of each area, with the white pixel areas representing convex parts and the black pixel areas representing concave parts, it is possible to determine whether the unevenness of the indentation depth, etc. is good or bad. If the unevenness is appropriate, the area value of the black pixels on the image will be appropriate, and if the unevenness is insufficient, the area value of the black pixels on the image will be insufficient. This makes it possible to grasp the difference in the uneven state even when imaging a processing target sheet made of the same material with a uniform light reflectance, even if the difference in the regular reflection component cannot be found. Moreover, by irradiating various patterned lights, it is possible to obtain data on the minute shadows of the uneven parts from multiple angles. This makes it possible to clearly capture not only the depth of the indentations in the uneven parts but also various uneven conditions (size in the planar direction, shape, arrangement pattern, etc.) in the first inspection image generation process (process (II-3)) based on multiple images (original images). This improves the inspection accuracy of determining whether the uneven condition is good or bad based on the generated surface shape image (processes (II-4) and (II-5)). The oblique direction of the pattern light L can be appropriately set so as to generate shadows in accordance with the pattern of the concave and convex portions. A preferred range of the oblique direction will be described later.

[0019] The above is not limited to the absorbent articles and packaging bodies described above, but also applies to determining whether the unevenness of uneven portions in various other target sheets is good or bad. In other words, according to the method for manufacturing a sheet member of the present invention, it is possible to improve the in-line inspection accuracy for various target sheets and thereby improve the manufacturing stability of the manufacturing method.

[0020] As shown in the above example, the threshold value in the judgment step (step (II-5)) is preferably set by determining the quality of an actual sample, setting a required value for that quality, and setting both or either of the upper and lower limits of the image measurement value of the corresponding uneven portion. It is preferable to set the threshold value for each inspection area. In addition, when determining the threshold value, it is preferable to construct a relational expression between the image measurement value and the numerical value related to the quality measured from the actual sample.

[0021] As an example of a method for manufacturing a sheet-like member of the present invention, a method for manufacturing a package 10 including an inspection step for the uneven portion shown in Fig. 1 will be described below. However, the method for manufacturing a sheet-like member of the present invention is not limited to the method for manufacturing a package 10.

[0022] As a manufacturing apparatus for carrying out the manufacturing method of this embodiment, for example, a manufacturing apparatus 100 shown in FIG. 4 can be mentioned. The manufacturing apparatus 100 includes a processing apparatus 110 that performs the above-mentioned step (I) and an inspection apparatus 120 that performs the step (II). The inspection device 120 includes an illumination device 130 that performs the above-mentioned step (II-1), an imaging device 140 that performs step (II-2), and an image processing device 150 that performs steps (II-3) to (II-5).

[0023] Image processing device 150 has a first inspection image generation unit 151 that performs step (II-3), an uneven portion measurement unit 155 that performs step (II-4), and a determination unit 156 that performs step (II-5) (FIG. 6). Image processing device 150 has a memory unit 157 that stores received image data, signals, etc., and generated image data, etc. Furthermore, image processing device 150 preferably includes a second inspection image generation unit 152 and an inspection image calculation unit 154, which will be described later. The image processing device 150 may include each of the above units as an independent structure, or may include them as an integrated structure. In an integrated structure, it is preferable to include software that realizes the functions of each of the above units. It is also preferable to include various interfaces, etc.

[0024] The manufacturing apparatus 100 further includes a transfer mechanism 160 and a line controller 170 as shown in FIG. The transfer mechanism 160 has the function of transferring the continuous body 12 of packaging bodies (hereinafter simply referred to as the continuous body 12) processed by the processing device 110 along the conveying direction Y to the inspection device 120 and further to the finishing processing device 180 described below. The line controller 170 controls the transport mechanism 160, the inspection device 120, and the discharge device 185 in the finishing processing device 180. These will be described in detail later.

[0025] First, the processing device 110 and step (I) will be described. The processing device 110 is a sealing unit that combines a pattern roll 112 having a plurality of pattern seal protrusions 111 on its peripheral surface with an anvil roll 113 (hereinafter, the processing device 110 is also referred to as the sealing unit 110). With this, a processing step (step (I)) of forming protrusions and recesses on the processing target sheet is performed as follows.

[0026] Upstream of the processing device 110, the packaged items 1 are intermittently placed between long covering sheets 2, 2 unwound from a roll of raw material to form a stack 11 (not shown). The stack 11 is transferred to the processing device 110. The pair of covering sheets 2, 2 may be sheets of the same material or sheets of different materials. In the processing device 110, a pattern roll 112 and an anvil roll 113 rotate continuously to continuously form pattern seals (concave and concave portions) corresponding to the pattern seal convex portions 111 on the cover sheets (processing target sheets) 2, 2 of the laminate 11. For example, as shown in FIG. 1, vertical seal portions 31 extending along the conveyance direction Y and horizontal seal portions 32 extending along the width direction X perpendicular to the conveyance direction Y are continuously formed. The vertical seal portion 31 and the horizontal seal portion 32 are formed as portions where a pair of cover sheets 2, 2 are sealed together at a position where the packaged item 1 is not present. The vertical seal portion 31 and the horizontal seal portion 32 become the uneven portion 3 in the cover sheets (sheets to be processed) 2, 2. The uneven portion 3 is formed on the cover sheet 2, which is the same material with a uniform light reflectance. In this way, the laminate 11 has the uneven portion 3 formed by the pattern seal described above, and becomes a continuous body 12 of packaging bodies.

[0027] The converting device 110 has a position detector 114 connected to the pattern roll 112 . The position detector 114 generates a signal Z1 in response to a division in the conveying direction Y that becomes the sheet-like packaging body 10 in the finishing processing device 180, which will be described later, and transmits the signal Z1 to a line controller 170, which will be described later. In other words, the generation of the signal Z1 by the position detector 114 is performed in response to a division in the conveying direction Y that corresponds to the packaging body 10 in the pattern seal protrusion 111. For example, at the timing when the pattern seal protrusion 111 of the pattern roll 112 forms the horizontal seal portion 32 shown in FIG. 1 , the position detector 114 generates a signal Z1 and transmits it to a timing control unit 172 that the line controller 170 has. This signal Z1 is one element that specifies the inspection position 121 in the inspection device 120 under the control of the line controller 170. The processing device 110 can be changed as needed if the processing content or the sheet to be processed changes.

[0028] The continuous body 12 that has been pattern sealed in the processing device 110 is transferred to the inspection device 120 by the transport mechanism 160. The specific configuration of the transport mechanism 160 is not limited as long as it transports the continuum 12 to the inspection device 120. For example, the transport mechanism 160 includes two rolls 161 and 162 and a conveyor belt 163 wound around the rolls and arranged to be rotatable. At least one of the rolls, for example, the roll 162, is preferably provided with a motor 164 as a drive device for rotating the roll. The drive system of the motor 164 may be a belt drive connecting a motor shaft (not shown) and a roll shaft (not shown), a direct drive in which the motor shaft directly drives the roll shaft, or another drive system. The motor 164 is driven by a drive signal Z2 from a motor control unit 171 included in the line controller 170. A motor amplifier 166 that amplifies the drive signal to an appropriate drive voltage is preferably disposed between the motor control unit 171 and the motor 164. An encoder 165 is preferably further connected to the motor 164. The encoder 165 outputs a change in mechanical position as an electrical signal. For example, it outputs a pulse signal Z3 in synchronization with the rotation of the motor 164. The encoder 165 may also measure the rotational position (e.g., rotation angle) and rotational speed (e.g., angular velocity) of the drive shaft (not shown) of the motor 164 using a sensor (not shown) and output the measurement results as an electrical signal. If the rotational position and rotational speed of the motor 164 can be measured, it is possible to determine the inspection position (e.g., the position of the horizontal seal unit 32) 121 and the transport speed of the continuum 12 on the conveyor belt 163 of the transport mechanism 160, which moves in conjunction with the motor 164. The encoder 165 may be, for example, a rotary encoder. The motor amplifier 166 receives a drive signal Z2 from a motor control unit 171 included in a line controller 170 (described later), amplifies the signal to an appropriate voltage for driving the motor 164, and sends the voltage to the motor 164. Furthermore, the motor amplifier 166 transmits a pulse signal Z3 output by the encoder 165 to an image processing device 150 included in an inspection device 120 (described later).

[0029] The line controller 170 includes a motor control unit 171 , a timing control unit 172 , and a discharge control unit 173 . As described above, the motor control unit 171 sends the drive signal Z2 of the target value of the motor 164, such as the number of rotations or the rotation speed, to the motor amplifier 166. The timing control unit 172 receives a signal Z1 generated by the position detector 114 in response to a division in the conveying direction Y corresponding to the packaging body 10 in the pattern seal convex portion 111. Based on this, the timing control unit 172 transmits a trigger signal Z4, which is a signal to start inspection, to the image processing device 150. After receiving the trigger signal Z4, the image processing device 150 receives a pulse signal Z3 and performs imaging. That is, after receiving the trigger signal Z4, imaging is performed in response to the pulse signal Z3. The pulse signal Z3 is transmitted from the encoder 165 each time the continuum 12 advances a predetermined distance. For example, the pulse signal Z3 is transmitted multiple times for a length corresponding to one packaging body 10 in the conveying direction Y. When a line scan camera is used as described below, imaging is performed for a predetermined number of lines, and the pulse signal Z3 is set to match this number of lines. The discharge control unit 173 transmits a discharge signal Z6 for the package 10 (sheet-like member) determined to have a poor seal by the image processing device 150 to a discharge device 185 in the finishing processing device 180, which will be described later, based on whether or not the image processing device 150 has transmitted an inspection determination signal Z5 (ON or OFF). Furthermore, based on the discharge signal Z6 transmitted in response to whether or not the image processing device 150 has transmitted an inspection determination signal Z5 (ON or OFF), the discharge control unit 173 determines how many members must pass before they are discharged, based on the distance from the inspection location to the discharge device 185 and the conveying speed of the production line.

[0030] Next, the inspection device 120 and step (II) will be described. As described above, the inspection device 120 has the lighting device 130, the imaging device 140, and the image processing device 150. These devices are used to perform an inspection step (step (II)) of determining the uneven state of the processed uneven portion 3 on the surface of the cover sheet (processing target sheet) 2.

[0031] The illumination device 130 irradiates light onto the inspection position 121 including the concave-convex portion 3 of the cover sheet 2 of the continuum 12. Specifically, the illumination device 130 irradiates light onto the inspection position 121 including the concave-convex portion 3 of the cover sheet 2 of the continuum 12. P The diagonal direction (perpendicular L P angle θL A plurality of patterned lights are sequentially irradiated onto the concave-convex portion 3 from the tilted direction (step (II-1); illumination step). L The irradiation angle θ L The perpendicular line is determined based on the surface of the covering sheet (sheet to be processed) 2. At the position of the uneven portion 3, the surface that serves as the reference is the outermost surface of the convex portion or the base of the concave portion. When the covering sheet (sheet to be processed) 2 is transported on a flat surface, the perpendicular line is determined to the surface along the transport direction, and when it is transported on a roll, the perpendicular line is determined to the tangent to the surface along the circumferential surface of the roll. The imaging device 140 captures an image at the timing when a plurality of pattern lights are irradiated from the illumination device 130 (step (II-2); imaging step). As a result, a plurality of images corresponding to the plurality of pattern lights are generated for one imaging target at the inspection position 121. In this way, images are captured in response to irradiation of multiple pattern lights from oblique directions, so even if the uneven portion 3 of the covering sheet 2 is made of the same material with a uniform light reflectance, the fine uneven state can be obtained as data on the difference in light intensity in multiple images (original images).

[0032] The timing of light emission of the lighting device 130 is controlled by the timing control section 172 included in the line controller 170 described above. That is, after the trigger signal Z4 from the timing control unit 172 is input to the image processing device 150, the first pattern light is emitted at the timing when the first pulse signal Z3 (first line) rises, and an image corresponding to the first pattern light is captured. This emission of pattern light and capturing of image is repeated for the first line of the image capture target as many times as the number of pattern light. For example, in the case of eight striped pattern light 103A shown in FIG. 5(A), this is repeated eight times. Then, when the next pulse signal Z3 rises, the above emission of pattern light and capturing of image is repeated again for the second line of the image capture target as many times as the number of pattern light. The shutter speed and other settings are set so that this repetition of light emission and image capture for one line can be completed before the next pulse signal Z3 rises. For example, if the number of lines to be captured is set to 100 and the eight striped pattern light shown in Figure 5(A) is used, images will be captured 8 x 100 times, and eight images will be generated, each with 100 pixels in the flow direction (Y direction) on the image (the X direction is determined by the number of pixels in the camera). This results in multiple images corresponding to the multiple pattern light.

[0033] Various types of lighting devices can be used as the lighting device 130, which can sequentially emit illumination light consisting of multiple pattern lights (irregular pattern lights). For example, a striped pattern lighting device can be used, which can sequentially emit pattern light having a striped illumination distribution while changing the phase of the illumination distribution. In the lighting device 130, the multiple pattern lights are generated by changing the phase of the striped illuminance distribution. Furthermore, when all of the multiple patterns are combined, the entire surface is illuminated. One example of such a lighting device is one having eight stripe pattern lights 130A as shown in FIG. 5(A). The lighting device having the striped pattern 130A shown in Fig. 5(A) can emit eight striped pattern light patterns in one line. Patterns 1 to 4 are obtained by changing the phase of the striped illuminance distribution in the width direction X of the continuum 12. Patterns 5 to 8 are obtained by changing the phase of the striped illuminance distribution in the transfer direction Y of the continuum 12. The shape and number of patterned lights of the illumination device 130 are not limited to those described above. Any illumination device that can accurately acquire data on the unevenness state and emits various patterned lights used in the patterned light projection method can be used. Another specific example of the illumination device 130 will be described later in connection with the manufacturing apparatus 200.

[0034] The imaging device 140 may be, for example, a line scan camera (line sensor). If the object to be imaged is a continuously transported object such as the continuum 12, the line scan camera is preferable, but imaging can also be performed using an area camera. The area camera will be described later in connection with the manufacturing apparatus 200. The imaging device 140 is not limited to the above, and various measuring devices capable of detecting the uneven state of the sheet can be used. In the imaging device 140, when the illumination device 130 irradiates eight stripe patterns 130A shown in Fig. 5(A) is used, an image is captured at the timing when the uneven portion 3 of one imaging target at the inspection position 121 is irradiated, and eight images corresponding to the irradiation pattern are generated (Fig. 5(B)). However, the multiple images captured and generated by the imaging device 140 are obtained according to the shape and number of pattern lights of the illumination device 130.

[0035] The imaging area using the imaging device 140 may be set to any range of the continuum 12 as long as the uneven portion (seal portion) 3 can be imaged. For example, the image may be taken so that the horizontal seal portion 32 is at the center of the image. Alternatively, the packaged item 1 may be positioned at the center of the image, and the image may include the front and rear horizontal seal portions 32 in the conveyance direction Y.

[0036] The acquired images (original images) are stored in the storage unit 157 in the image processing device 150 (FIG. 6).

[0037] Next, the image processing device 150 generates a surface profile image (inspection image) as shown in Fig. 5(C) from the acquired multiple images (eight images in the above embodiment) (step (II-3); first inspection image generation step). The surface profile image shown in Fig. 5(C) includes an image of the horizontal seal portion 32 in the package continuum 12. The image processing device 150 performs step (II-3) in a first inspection image generating unit 151 (FIG. 6) within the image processing device 150. That is, the first inspection image generating unit 151 extracts and synthesizes components (data) indicating the uneven state according to the size of the uneven portion 3 (height difference between the concave and convex portions, and area in the planar direction of the concave and convex portions) from the plurality of images acquired in steps (II-1) and (II-2) and stored in the storage unit 157. In this way, a surface shape image indicating the shape of the surface of the processing target sheet (covering sheet 2 of the continuum 12) is generated.

[0038] In the "extraction of components showing the uneven state according to the size of the uneven portion 3" mentioned above, the feature size, which is one of the extraction parameters, is set according to the actual size of the uneven portion 3. The "feature size" is the number of pixels to be extracted. By increasing this feature size, gentle unevenness can be highlighted, and by decreasing it, small, deep unevenness can be highlighted. For example, if the width of a depression (black pixels) on the image is 15 pixels, the feature size can be set to 15.

[0039] By appropriately changing the generation conditions in this manner, the first inspection image generation unit 151 extracts and synthesizes components indicating the uneven state that matches the size of the uneven portion 3 from each of the multiple acquired images (eight images in this embodiment) to generate a single surface shape image. For example, consider the surface topography image (example of the present invention) in Figure 7(A). In the surface topography image in Figure 7(A), the feature size is set to 15 pixels, corresponding to the width of the recesses (15 pixels). This clearly shows the difference in shading between the black pixels of the recesses and the white pixels of the protrusions. This clearly shows the difference in shading between the recesses and the protrusions compared to the specular reflection image (comparison example) in Figure 7(B) that was synthesized by extracting the specular reflection component. Furthermore, in the surface topography image in Figure 7(C), the feature size is set to 4, which does not match the width of the recesses (the feature size is too small), and therefore the image does not clearly show the unevenness like that in Figure 7(A). In addition, in the specular reflection image in Figure 7(B) where the specular reflection component is extracted, the covering sheet 2 is made of the same material, so it is difficult to see the difference in shading in the specular reflection component, resulting in an overall dark image.

[0040] The generated surface shape image is stored in the storage unit 157 in the image processing device 150 (FIG. 6).

[0041] Next, the image processing device 150 performs the uneven portion measurement step of step (II-4) in the uneven portion measurement unit 155 (FIG. 6) within the image processing device 150. That is, the uneven portion measurement unit 155 sets at least one inspection area in the surface shape image stored in the storage unit 157. In the set inspection area, the image measurement values ​​of the uneven portion 3 are calculated. The image measurement values ​​of the uneven portion 3 are stored in the storage unit 157 within the image processing device 150 (FIG. 6). In this case, it is preferable to perform preprocessing on the generated surface shape image, such as shading correction and binarization. For example, by performing binarization, the distinction between the convex portions of white pixels and the concave portions of black pixels in the inspection area of ​​the horizontal seal portion 32 becomes clearer.

[0042] The inspection area for the uneven portion 3 is preferably set according to the position of each uneven portion (seal portion) 3. The size of the inspection area may include the entire uneven portion (seal portion) 3, or may be set to cover only a portion of it. For example, as shown in FIG. 8, within an imaging area M in the continuum 12, inspection areas T1 and T2 are set for the image of the horizontal seal portion 32, and inspection areas T3 to T5 are set for the image of the vertical seal portion 31. In this case, each inspection area may be set to cover the entire horizontal seal portion 32 and vertical seal portion 31 within the imaging area M, or may be set to cover only a portion of them. The inspection area may be set to include the concave-convex portion and a non-convex portion (to be described later) in addition to the concave-convex portion. For example, the inspection area may be set to extend from the concave-convex portion to the adjacent non-convex portion.

[0043] The image measurement value of the uneven portion 3 means a value that can be read from the image and indicates the uneven state in the inspection area. Examples of such image measurement values ​​include the area value of the uneven portion 3 in the inspection area, the gray value (e.g., a grayscale value with 256 gradations), and the correlation value with a pre-registered uneven pattern (e.g., the pattern match rate or mismatch rate).

[0044] Next, the image processing device 150 performs the judgment step of step (II-5) in the judgment unit 156 (FIG. 6) within the image processing device 150. At this time, a threshold value for each inspection area is set in advance in the memory unit 157. It is preferable to determine the quality of an actual sample, set a required value for that quality, and set the threshold value as both or one of the upper and lower limits of the image measurement value of the concave-convex portion 3 corresponding to that quality. For example, a lower limit of the required seal strength for the horizontal seal portion 32 of one inspection area can be set, and the corresponding lower limit of the black area value (area value of black pixels indicating concave portions) in the concave-convex portion 3 can be set as the threshold. It is preferable to set a threshold value for each inspection area. Furthermore, when determining the threshold, it is preferable to establish a relationship between the image measurement value and the numerical value related to the quality measured from the actual sample. For example, in two inspection areas T1 and T2 (FIG. 8) for the horizontal seal portion 32, a relational expression (calibration curve) is constructed between the black area value (area value of black pixels indicating recesses) measured from an image and the seal strength (N / 15 mm) measured from an actual sample, as shown in FIGS. 9(A) and 9(B). For each of the inspection areas T1 and T2, the lower limit of the black area value corresponding to the lower limit of the seal strength can be set as a threshold value.

[0045] The determination unit 156 compares the image measurement value of the uneven portion (seal portion) 3 with the threshold value and determines whether the uneven state of the uneven portion 3 is good or bad. That is, if the "image measurement value of the uneven portion (seal portion) 3 ≧ the threshold value", it is determined to be "good", and if the "image measurement value of the uneven portion (seal portion) 3 < the threshold value", it is determined to be "bad".

[0046] In this way, according to the manufacturing method for sheet-like articles of this embodiment, it is possible to clearly capture the differences in the uneven state of the uneven portions formed on the sheet to be processed in-line, thereby increasing inspection accuracy and improving manufacturing stability in the manufacturing method. In this regard, for example, in the surface profile images (samples 1 and 2) generated based on images captured by pattern illumination in Figures 10(A) and (B), which are examples of the present invention, as shown in Figure 10(C), in both inspection areas T11 and T12, sample 1 with a seal strength of 3.8 N / 15 mm has a clearly larger black area value (area value of black pixels indicating recesses) than sample 2 with a seal strength of 2.1 N / 15 mm, indicating that the black area value correlates with seal strength. In this way, by using a surface profile image generated based on in-line pattern illumination and tailored to the size of the uneven portion, the inspection accuracy for determining whether the uneven state of the uneven portion 3 is good or bad can be improved. In contrast, in the comparative images (Samples 1 and 2) obtained by full-surface illumination in Figures 10(D) and (E), the difference in black area value between Sample 1 and Sample 2, which have different seal strengths, is smaller than the above in both inspection areas T11 and T12, as shown in Figure 10(F). In other words, the difference in black area value does not clearly reflect the difference in seal strength as described above. Thus, according to the method for manufacturing sheet-like articles of this embodiment, the difference in shading of the uneven state can be made clear in images inspected in-line, thereby increasing inspection accuracy and improving the manufacturing stability of the manufacturing method.

[0047] In the method for manufacturing a sheet-like member of this embodiment, from the viewpoint of further clarifying the difference in shading of the uneven state in the surface shape image, it is preferable to set the imaging conditions for the multiple images (original images) that form the basis of the surface shape image as follows: That is, it is preferable to set the installation conditions for the illumination device 130 and the imaging device 140 that carry out steps (II-1) and (II-2) as follows:

[0048] Angle θ of the lighting device 130 L is the perpendicular line L of the imaging device 140 P Angle θ to c The sum of the angle θ L +angle θ c (the angle between the illumination device 130 and the image capture device 140). L +angle θ c" is preferably 60 degrees or more, more preferably 70 degrees or more, and even more preferably 80 degrees or more. "Angle θ L +angle θ c It is preferable that the upper limit of the angle θ be as large as possible as long as the illumination device 130 does not mechanically interfere with the continuum 12 or the transport mechanism 160. L +angle θ c The larger " is, the clearer the difference in shading of the uneven portion 3 due to the shadow becomes in the captured image and in the surface shape image generated based on the captured image, which is preferable. Angle θ of the imaging device 140 c From the same viewpoint as above, the angle θ is preferably 20 degrees or more, more preferably 25 degrees or more, and even more preferably 30 degrees or more. c is preferably 45 degrees or less, from the viewpoint of making it easier for the imaging device 140 to capture the pattern light at a certain angle relative to the continuum 12.

[0049] For example, as shown in FIG. 11, in a surface shape image in which a part of the horizontal seal portion 32 of the continuum 12 is set as an inspection region (total pixel area value: 1440 pixels), L +Angle θ of the imaging device 140 c As the value of " is increased, the black area value (the area value of the black pixels that indicate the concave portions) increases, and the difference in density between the concave portions (black pixels) and the convex portions (white pixels) becomes clearer. Also, for example, as shown in FIG. 11, the angle θ c As the value increases, the black area value (the area value of the black pixels that indicate the recesses) increases, and the difference in density becomes clearer. In this way, the angle θ of the lighting device 130 L +Angle θ of the imaging device 140 c It is preferable that the angle θ of the image pickup device 140 is 60 degrees or more. c is 20 degrees or more, and the angle θ of the lighting device 130 L +Angle θ of the imaging device 140 c It is more preferable that the angle be 60 degrees or more.

[0050] 4, the illumination device 130 and the imaging device 140 are preferably disposed opposite each other along the conveying direction Y with the inspection position 121 in between. This allows the pattern light to be more effectively irradiated onto the continuum 12 passing through the inspection position 121 at a constant speed, making it easier for the imaging device 140 to capture the pattern light and capture a clearer image.

[0051] In the method for producing a sheet-like article of this embodiment, from the viewpoint of further improving the inspection accuracy, it is preferable to perform the inspection step (II) in a multi-layered manner as follows. That is, as shown in FIG. 12, for a plurality of images (original images) (FIG. 12(B)) acquired in step (II-1) and step (II-2) using a plurality of pattern lights (FIG. 12(A)), an average image (inspection image) (FIG. 12(D)) is generated together with the above-mentioned surface shape image (inspection image) (FIG. 12(C)). Calculation and judgment of step (II-4) and step (II-5) may be performed based on both the generated inspection images. Furthermore, the above-mentioned surface shape image and average image are calculated to generate a calculated image (inspection image) (FIG. 12(E)). Calculation and judgment of step (II-4) and step (II-5) may be performed based on these surface shape image, average image and calculated image. This multi-layered inspection process is more effective, for example, when the unevenness 3 has a finer and deeper shape and the boundaries between adjacent unevenness 3 (boundaries between convex portions, boundaries between concave portions) are blurred on the image (adjacent concave or convex portions appear as a mass on the image). This will be explained below with reference to FIG.

[0052] As shown in FIG. 13, in step S1, a plurality of pattern lights are sequentially irradiated from an oblique direction toward the uneven portion 3 (step (II-1)), and at the timing when the plurality of pattern lights are irradiated, the imaging device 140 receives and captures the reflected light, thereby generating a plurality of images corresponding to the plurality of pattern lights ((II-2)). Next, in step S2, the above-mentioned surface shape image is generated ((II-3)). In response to this, in step J1, it is determined whether or not it is necessary to generate an average image (Figure 12(D)). This is determined based on whether or not the surface shape image alone is insufficient. For example, if the correlation between the image measurement value of the uneven portion 3 and the numerical value related to quality is weak and a threshold cannot be determined using only the surface shape image, or if the uneven portion 3 is blurred on the image and needs to be made clearer (Yes), the process proceeds to the next step S3. If it is determined that this is not necessary (No), the process jumps to step S5. Note that in the method for manufacturing a sheet-like member of this embodiment, it is also possible to proceed to step S3 immediately after step S2 without making the determination in step J1.

[0053] In step S3, the multiple images (original images) acquired in steps (II-1) and (II-2) are averaged to generate an average image (second inspection image generation step; also referred to as step (II-3-2)). In the manufacturing apparatus 100 shown in FIG. 4, the second inspection image generation unit 152 in the image processing device 150 shown in FIG. 6 retrieves the multiple images (original images) (FIG. 12(B)) from the storage unit 157 and performs averaging processing to generate an average image (FIG. 12(D)). The average image is also stored in the storage unit 157, similar to the surface shape image. The first inspection image generation process for generating a surface shape image and the second inspection image generation process for generating an average image are also collectively referred to as the inspection image generation process. In manufacturing apparatus 100, first inspection image generation unit 151 and second inspection image generation unit 152 are also collectively referred to as inspection image generation unit 153.

[0054] Furthermore, in response to this, in step J2, it is determined whether or not it is necessary to generate a calculated image (Figure 12(E)). This is determined based on whether or not the surface shape image and average image alone are insufficient. For example, if the correlation between the image measurement value of the uneven portion 3 and the quality-related numerical value is weak and a threshold cannot be determined using only the surface shape image and average image, or if the uneven portion 3 is blurred on the image and needs to be made clearer (Yes), the process proceeds to the next step S4. If it is determined that this is not necessary (No), the process jumps to step S5. Note that in the method for manufacturing a sheet-like member of this embodiment, it is also possible to proceed to step S4 immediately after step S3 without making the determination in step J2.

[0055] In step S4, the surface shape image obtained in step S2 (step (II-3); first inspection image generation step) and the average image obtained in step S3 (step (II-3-2); second inspection image generation step) are calculated to generate a calculated image (FIG. 12(E)) (inspection image calculation step; also referred to as step (II-3-3)). The calculation in this inspection image calculation step preferably clarifies the unevenness pattern based on the surface shape image and the average image. For example, the clarification is preferably achieved by increasing the difference in shading between the concave and convex portions. This calculation can be performed by various methods. For example, a process that whitens the image of the convex portions is preferred. Specific examples include a minimum value calculation (generating an image using the smaller pixel value) and an addition calculation (generating an added image; pixel values ​​of 255 or higher are fixed at 255). This makes the difference in shading between the concave and convex portions more distinct. Furthermore, blurring of the boundary of the concave and convex portions 3 in the image (where adjacent concave or convex portions appear as a single block in the image) can be eliminated. In the manufacturing apparatus 100 shown in Fig. 4, the inspection image calculation unit 154 in the image processing device 150 shown in Fig. 6 retrieves the surface shape image and the average image (Figs. 12(C) and (D)) from the storage unit 157, performs calculations on them, and generates a calculated image (Fig. 12(E)). The calculated image is also stored in the storage unit 157, just like the surface shape image and the average image.

[0056] FIG. 14 shows a specific example of the inspection image calculation process. The surface shape image (FIG. 14(A)) and the average image (FIG. 14(C)) are subjected to minimum value calculation to generate calculated image example 1 (FIG. 14(D)). Similarly, the surface shape image (FIG. 14(A)) and the average image (FIG. 14(C)) are added together to generate an example calculated image 2 (FIG. 14(F)). 14(E) and (G), which are enlarged views of the inspection area T1 in the calculated image example 1 and the calculated image example 2, show a more pronounced difference in shading between the concave and convex states than in the enlarged view of the surface shape image in FIG. 14(B). This difference becomes even more apparent when a binarization process, which is a preferred process performed in step (II-4), is performed.

[0057] Steps S5 and S6 correspond to the uneven portion measuring step of step (II-4). Step S5 is a preprocessing step for step S6, and is performed on at least one test image. Examples of preprocessing include the binarization process described above as a preferred process. Preprocessing may include not only binarization but also shading correction, and may include various processes that are typically performed in image processing. As described above, in step S6, at least one inspection area is set for the uneven portion 3, and image measurement values ​​of the uneven portion 3 are calculated. These image measurement values ​​are calculated for each of the generated inspection images. That is, if only a surface shape image has been generated (determined "No" in step J1), at least one inspection area is set for the uneven portion 3 in the surface shape image, and image measurement values ​​of the uneven portion 3 are calculated. If a surface shape image and an average image have been generated (determined "No" in step J2), at least one inspection area is set for the uneven portion 3 in each of the surface shape image and the average image, and image measurement values ​​of the uneven portion 3 are calculated. If a surface shape image, average image, and calculated image have been generated, at least one inspection area is set for the uneven portion 3 in each of the surface shape image, average image, and calculated image, and image measurement values ​​of the uneven portion 3 are calculated. It is preferable to calculate multiple image measurement values ​​by using one or more of the surface shape image, average image, and calculated image, changing the measurement content and measurement position for each. This allows for multi-layered inspection, improving inspection accuracy. In the manufacturing apparatus 100 shown in Fig. 4, these measurements are performed by the unevenness measurement unit 155 in the image processing device 150 shown in Fig. 6, which retrieves various inspection images (Figs. 12(C), (D), and (E)) from the storage unit 157. The image measurement values ​​are also stored in the storage unit 157.

[0058] 13, the process includes a decision in step J3 and a step S7, but the decision in step J3 and the step S7 may not be included. In step J3, it is determined whether or not measurement of non-convex and concave portions is necessary. "Non-convex and concave portions" refers to the portions of the surface of the sheet to be processed other than the concave and convex portions formed by processing. Examples include the area between the concave and convex portions and the packaged item, and the area where the packaged item is placed. If it is determined that measurement is necessary (Yes), proceed to step S7. If it is determined that measurement is not necessary (No), jump to step J4. In step S7, a non-convexo-concave portion measurement step is performed in which at least one inspection area is set for the non-concave portion in each of the generated inspection images, and image measurement values ​​of the non-concave portion are calculated. In this step, the inspection area may be set to include the concave / convex portion in the non-concave portion. For example, the inspection area may be set to extend from the non-concave portion to the adjacent concave / convex portion. Examples of image measurement values ​​of the non-concave portion include the distance between the concave / convex portion and the packaged item in the non-concave portion, the shading value of the non-concave portion, and a value indicating the presence or absence of the packaged item in the non-concave portion.

[0059] Next, in step J4, the judgment step (II-5) is performed, in which various image measurement values ​​are compared with preset thresholds to judge whether the unevenness state is good or bad. The following shows the cases where the inspection image is only a surface shape image, where an average image is added to this, and where a calculated image is further added. If the generated inspection image is only a surface shape image, the image measurement values ​​of the uneven portions and the image measurement values ​​of the non-uneven portions in the surface shape image are compared with a preset threshold value to determine whether the uneven state is good or bad. If the generated inspection images are a surface shape image and an average image, the image measurement values ​​of the uneven and non-uneven parts in the surface shape image, as well as the image measurement values ​​of the uneven and non-uneven parts in the average image, are compared with predetermined thresholds to determine whether the uneven state is good or bad. If the generated inspection images are a surface shape image, an average image, and a calculated image, the image measurement values ​​of the uneven and non-uneven parts in the surface shape image, the image measurement values ​​of the uneven and non-uneven parts in the average image, and the image measurement values ​​of the uneven and non-uneven parts in the calculated image are each compared with a predetermined threshold value to determine whether the uneven state is good or bad. In the image processing device 150 shown in FIG. 4, the determination unit 156 in the image processing device 150 shown in FIG. 6 retrieves image measurement values ​​of various inspection images from the storage unit 157 to perform these operations. Note that the above is shown as including steps J3 and S7 relating to non-convex and concave portions, but if the aforementioned steps J3 and S7 are not included, the above pass / fail judgment is made without including the image measurement values ​​of the non-convex and concave portions.

[0060] In step J4, the image measurement values ​​of all the generated inspection images are used as the basis for determining whether the inspection object is good or bad. If any one of the judgment results is "bad," the inspection object is determined to be "bad" (No).

[0061] In step S8, if the judgment result is "good" (Yes), the inspection judgment signal Z5 is set to "ON." If the judgment result is "bad" (No), the inspection judgment signal Z5 is set to "OFF." In the manufacturing method of the sheet-like member of this embodiment, after the continuous body 12 is divided into individual packages 10, it is preferable to carry out a sorting process in which defective products whose inspection determination signal Z5 is "OFF" are removed from the line and good products whose inspection determination signal Z5 is "ON" are transported downstream. Furthermore, in the method for manufacturing a sheet-like member of this embodiment, if a defect (judgment signal "OFF") is detected based on the results of the inspection process (process (II)), an alarm may be output to notify of a processing defect, or the manufacturing equipment may be stopped.

[0062] In the manufacturing apparatus 100 shown in FIG. 4, these are performed by the finishing processing device 180, the determining unit 156 of the image processing device 150, and the discharge control unit 173 of the line controller 170. The finishing processing device 180 includes a cutting section 181 and a discharge device 185 . An example of the cutting unit 181 is a rotary cutter. The rotary cutter is made up of opposing rolls 182 and 183, with a cutter 184 disposed on one of the rolls 183. After the continuous body 12 of packaging bodies that has been subjected to pattern sealing processing has completed the inspection process, it is cut into individual packaging bodies 10 by the cutting unit 181. At the same time, the determination unit 156 of the image processing device 150, the discharge control unit 173 of the line controller 170, and the discharge device 185 cooperate to process the individual packaging bodies 10 based on the above-mentioned determination results. First, if the product is determined to be a non-defective product, the determination unit 156 turns the inspection determination signal Z5 "ON." The inspection determination signal Z5 is transmitted from the determination unit 156 to the discharge control unit 173. That is, the determination unit 156 transmits a signal to transmit "OK" information to the discharge control unit 173. On the other hand, if the product is determined to be defective, the determination unit 156 turns the inspection determination signal Z5 "OFF." That is, the determination unit 156 does not transmit a signal to transmit "NG" information to the discharge control unit 173. When the discharge control unit 173 receives the inspection determination signal Z5 that has been turned "ON," the discharge device 185 does not operate, and good (OK) packages 10 are transported downstream. When the inspection determination signal Z5 is turned "OFF," the discharge control unit 173 sends a discharge signal Z6 to the discharge device 185, and the discharge device 185 identifies and discharges defective (NG) packages 10. Discharge is preferably performed by sending the defective parts down a line that collects defective parts. Defective packaging bodies 10 can be identified by the discharge control unit 173 based on information such as the timing at which the image judged by the judgment unit 156 was taken at the inspection position 121, the conveying speed of the production line, and the distance from the inspection position 121 to the cutting unit 181. In this judgment process, if there are many defective judgments (judgment signal is "OFF") detected based on the measured values, an alarm informing of the processing defect can be output to, for example, the image display device 190, as described above. If this continues, the manufacturing apparatus 100 can be stopped.

[0063] The sheet-like member manufactured as a non-defective product is assembled with other members to manufacture a desired product (sheet-like article). For example, the sheet-like member is laminated or joined with other members, cut, or otherwise assembled into a desired product (sheet-like article). Examples of such sheet-like articles include eye masks and napkins. Furthermore, a sheet-like member manufactured as a non-defective product may be assembled with other members to manufacture products other than sheet-like articles (for example, absorbent articles such as diapers).

[0064] The manufacturing apparatus for carrying out the method for manufacturing a sheet-shaped member of the present invention is not limited to the above-mentioned manufacturing apparatus 100 (FIG. 4). Another example of the manufacturing apparatus is a manufacturing apparatus 200 shown in FIG. In the manufacturing apparatus 200 shown in FIG. 15, the lighting device 130 and the imaging device 140 are different from those of the manufacturing apparatus 100 described above, but the rest are common to the manufacturing apparatus 100. The lighting device 130A in the manufacturing apparatus 200 uses a pattern light for an area camera. The pattern light is a donut-shaped circle, a so-called ring light. The inner wall surface of the ring light has four divided lighting sections, and four pattern lights are emitted. The four pattern lights are emitted obliquely from each arrangement position on the inner wall surface toward the inspection position 121. An area camera is used as the imaging device 140A in the manufacturing apparatus 200. The area camera captures images perpendicular to the inspection position 121, as shown in FIG. By using such an area camera in combination with the above-mentioned illumination device 130A, it becomes possible to perform appropriate imaging and appropriate image processing (generation and calculation of an inspection image) as described above. In other words, even when using the manufacturing device 200, it is possible to clearly capture the difference in the uneven state of the uneven portion imparted to the sheet to be processed in-line, thereby increasing inspection accuracy and improving production stability in the manufacturing method.

[0065] The sheet-like member manufacturing method and manufacturing apparatus of the present invention are not limited to the device configurations shown in the manufacturing apparatuses 100 and 200 described above. The configuration of each device can be changed as appropriate within the scope in which the above-mentioned effects can be achieved. For example, by appropriately changing the processing device, it can be used as a method for manufacturing various sheet-like members. Furthermore, multiple devices can be combined into one device. It can also be configured to include other devices. Furthermore, the inspection step (step (II)) can be performed on not only a continuous product but also a single-sheet product by changing the position of the inspection device.

[0066] In the sheet-like member manufacturing method and manufacturing apparatus of the present invention, the uneven portion to be inspected is not limited to the uneven portion 3 or the uneven portion 7 described above. Any uneven shape formed within the processing area can be inspected. Examples of such patterns include an uneven pattern in which a convex portion and a concave portion are adjacent to each other, a solid pattern in which a concave portion is adjacent to a non-convex portion (a convex portion of a solid pattern), and a solid pattern in which a convex portion is adjacent to a non-convex portion (a concave portion of a solid pattern). The uneven portion 42 in FIG. 16(A) is an uneven pattern in which convex portions (or concave portions) are arranged in a grid or dot pattern, and the convex portion and the concave portion are adjacent to each other. The uneven portion 43 in FIG. 16(B) is a concave portion or a convex portion of a solid pattern adjacent to a non-convex portion 41. In this way, the adjacent convex portions and concave portions clearly show the difference in shading between the uneven state in the inspection image described above, enabling highly accurate inspection. In particular, from the viewpoint of stably extracting the difference in shading, a concave-convex pattern having a plurality of convex and concave portions within the concave-convex portion is preferable, as shown in Fig. 16(A). From this viewpoint, a concave (or convex) portion 44 of a full solid pattern, as shown in Fig. 16(C), makes it difficult for the difference in shading of the concave-convex state to occur on the inspection image. However, even with a solid pattern, the above-mentioned inspection is possible if there is a boundary with a non-convex portion. [Explanation of symbols]

[0067] 10 Sheet-like packaging containing packaged items 11 Laminate 12 Continuous sheet-like packaging containing packaged items 100, 200 manufacturing equipment 110 Processing equipment 120 Inspection equipment 130 Lighting equipment 140 Imaging device 150 Image processing device 151 First inspection image generation unit 152 Second inspection image generation unit 153 Inspection image generation unit 154 Inspection image calculation unit 155 Unevenness measurement unit 156 Judgment section 180 Finishing treatment device T1~T5, T11, T12 examination areas

Claims

1. A method for manufacturing a sheet-like member having an uneven portion formed by processing, comprising: a processing step of forming the concave-convex portion on the processing target sheet; an inspection step of determining the uneven state of the processed uneven portion on the surface of the processing target sheet, The inspection step includes: an illumination step of sequentially irradiating the uneven portion with a plurality of pattern lights from a direction oblique to a line perpendicular to the surface of the processing target sheet; an imaging step of imaging the uneven portion at the timing when the plurality of pattern lights are irradiated, and generating a plurality of images corresponding to the plurality of pattern lights; a first inspection image generation step of extracting and synthesizing components that indicate the uneven state from the multiple images acquired in the imaging step in accordance with the size of the uneven portion, and generating a surface shape image that indicates the shape of the surface of the processing target sheet; an uneven portion measuring step of setting at least one inspection area for the uneven portion in the surface shape image and calculating an image measurement value of the uneven portion; a determining step of comparing the image measurement value of the uneven portion with a preset threshold value to determine whether the uneven state of the uneven portion is good or bad, A method for manufacturing a sheet-like member.

2. the inspection step includes a second inspection image generating step of averaging the plurality of images to generate an average image; In the uneven portion measuring step, at least one inspection area is set for the uneven portion for each of the surface shape image and the average image, and an image measurement value of the uneven portion is calculated; The judgment of pass / fail in the judgment step is performed by comparing the image measurement value of the uneven portion in the surface shape image and the image measurement value of the uneven portion in the average image with the preset threshold values, respectively. The method for producing the sheet-like member according to claim 1.

3. the inspection step includes an inspection image calculation step of calculating the surface shape image and the average image to generate a calculated image, In the uneven portion measuring step, at least one inspection area is set for the uneven portion for each of the surface shape image, the average image, and the calculated image, and an image measurement value of the uneven portion is calculated; the judgment of acceptability in the judgment step is performed by comparing the image measurement value of the uneven portion in the surface shape image, the image measurement value of the uneven portion in the average image, and the image measurement value of the uneven portion in the calculation image with the preset threshold values, respectively. The method for producing the sheet-like member according to claim 2.

4. The method for manufacturing a sheet member according to claim 3, wherein the inspection image calculation step generates a calculated image in which the uneven pattern is made clear.

5. a non-concave / convex portion measuring step of setting at least one inspection area for a non-concave / convex portion other than the concave / convex portion on the surface of the processing target sheet and calculating an image measurement value of the non-concave / convex portion; In the determining step, the quality of the uneven state is determined using the image measurement values ​​of the uneven portion and the image measurement values ​​of the non-uneven portion. The method for producing a sheet-like member according to any one of claims 1 to 4.

6. 6. The method for manufacturing a sheet-like member according to claim 5, wherein the image measurement values ​​of the non-convexoconcave portion include one or more of the distance between the concave-convex portion and the packaged item in the non-convexoconcave portion, the shading value of the non-convexoconcave portion, and a value indicating the presence or absence of the packaged item in the non-convexoconcave portion.

7. A method for manufacturing a sheet-like member according to any one of claims 1 to 4, wherein the image measurement values ​​of the uneven portion include one or more of an area value, a shading value, and a correlation value with a pre-registered uneven pattern of the uneven portion.

8. The method for manufacturing a sheet-like member according to any one of claims 1 to 4, wherein the plurality of patterned lights are generated by changing the phase of a striped illuminance distribution.

9. A method for producing a sheet-like article, comprising incorporating a sheet-like member obtained by the method for producing a sheet-like member according to any one of claims 1 to 4 to produce a sheet-like article.

10. An apparatus for manufacturing a sheet-like member having an uneven portion formed by processing, a processing device for forming the concave-convex portion on the processing target sheet; an inspection device for determining the uneven state of the processed uneven portion on the surface of the processing target sheet, The inspection device includes: an illumination device that sequentially irradiates a plurality of pattern lights toward the uneven portion from a direction oblique to a line perpendicular to the surface of the processing target sheet; an imaging device that captures an image of the uneven portion at a timing when the plurality of pattern lights are irradiated, and generates a plurality of images corresponding to the plurality of pattern lights; an image processing device based on a plurality of images acquired by the imaging device, The image processing device includes: a first inspection image generation unit that extracts and synthesizes components that indicate the uneven state from the multiple images acquired by the imaging device in accordance with the size of the uneven portion, and generates a surface shape image that indicates the shape of the surface of the processing target sheet; an unevenness measurement unit that sets at least one inspection area for the unevenness portion in the surface shape image and calculates image measurement values ​​of the unevenness portion; a determination unit that compares the image measurement value of the uneven portion with a preset threshold value to determine whether the uneven state of the uneven portion is good or bad, Sheet-shaped member manufacturing device.

11. the image processing device includes a second inspection image generation unit that averages the plurality of images to generate an average image; the uneven portion measuring unit sets at least one inspection area for the uneven portion for each of the surface shape image and the average image, and calculates image measurement values ​​of the uneven portion; the determining unit compares the image measurement value of the uneven portion in the surface shape image and the image measurement value of the uneven portion in the average image with the preset threshold values, respectively, to determine whether the image is good or bad. The sheet-like member manufacturing apparatus according to claim 10.

12. the image processing device includes an inspection image calculation unit that calculates the surface shape image and the average image to generate a calculated image; the uneven portion measuring unit sets at least one inspection area for the uneven portion for each of the surface shape image, the average image, and the calculated image, and calculates image measurement values ​​of the uneven portion; the determining unit compares the image measurement value of the uneven portion in the surface shape image, the image measurement value of the uneven portion in the average image, and the image measurement value of the uneven portion in the calculated image with the preset threshold values, respectively, to determine whether the image is good or bad. The sheet member manufacturing apparatus according to claim 11.

Images