Evaluation method and evaluation device

Abstract

The present invention enables quantitative the evaluation of a chalk mark. Provided is an evaluation method for evaluating a scratch on the surface of a substrate to be evaluated. With the evaluation method, an image of the surface of a substrate to be evaluated is acquired, a first range including a scratch and a second range including no scratch are individually extracted from the image, the difference between the luminance value in the first range and the luminance value in the second range is computed, and an evaluation result is obtained on the basis of the difference.

Description

Evaluation method and evaluation device

[0001] The present disclosure relates to an evaluation method and an evaluation device for evaluating the surface of a substrate.

[0002] The surface of a substrate may be evaluated to evaluate a composition, etc. For example, as a method for evaluating the surface of a substrate, the substrate may be scratched by a friction tester and the substrate may be evaluated based on the scratches formed on the surface of the substrate (see, for example, Patent Documents 1 and 2).

[0003] JP 2023-33719 A JP 2021-195407 A

[0004] In the evaluation methods described above, the evaluation is carried out visually, and it is not possible to quantitatively evaluate the surface of the substrate.

[0005] Therefore, an object of the present disclosure is to provide a method and apparatus that can quantitatively evaluate the surface of a substrate.

[0006] The evaluation method disclosed herein is a method for evaluating scratches on the surface of a substrate to be evaluated, comprising: acquiring an image of the surface of the substrate to be evaluated; extracting a first area having scratches and a second area having no scratches from the image; calculating a difference between the brightness value of the first area and the brightness value of the second area; and obtaining an evaluation result based on the difference.

[0007] In the evaluation method, before acquiring the image, a terminal of a friction tester may be reciprocated on the surface of the substrate to be evaluated, thereby scratching the surface of the substrate.

[0008] In the evaluation method, the substrate may be a textile.

[0009] In the evaluation method, the scratch may be a chalk mark on a textile.

[0010] In the evaluation method, the image may be an image captured by a camera in which the optical axis of the light irradiating the base material from a light source is set coaxially with the imaging axis of the camera.

[0011] In the evaluation method, the evaluation object may be scratched in a linear range of 10 mm or less in width by the friction tester.

[0012] In the evaluation method, the terminal may be reciprocated 10 times or less.

[0013] The evaluation method may involve scratching a predetermined position on the surface of the substrate to be evaluated by reciprocating a terminal with a predetermined load using the friction tester.

[0014] In the evaluation method, the predetermined load may be in the range of 100 g to 4000 g.

[0015] In the evaluation method, the predetermined load may be in the range of 1500 g to 4000 g.

[0016] The evaluation device disclosed herein has an arithmetic circuit and is used to evaluate scratches on the surface of a substrate to be evaluated, the evaluation device acquiring an image of the surface of the substrate, the arithmetic circuit extracting a first range containing scratches and a second range without scratches from the image, calculating a difference between the brightness values ​​of the first range and the brightness values ​​of the second range, and outputting an evaluation result based on the difference.

[0017] These general and specific aspects may be realized by a system, a method, and a computer program, as well as combinations thereof.

[0018] According to the evaluation method and evaluation device of the present disclosure, the surface of a substrate can be quantitatively evaluated.

[0019] FIG. 1 is a block diagram showing the configuration of an evaluation device. FIG. 2 is a conceptual diagram showing an evaluation object. FIG. 3 is a conceptual diagram showing an example of a region of an evaluation object extracted from an evaluation object. FIG. 4 is a conceptual diagram showing another example of a region of an evaluation object extracted from an evaluation object. FIG. 5 is a conceptual diagram explaining coaxial lighting, showing a coaxial lighting device and an imaging device together. FIG. 6 is a data configuration diagram explaining evaluation data. FIG. 7 is a flowchart explaining the processing of an evaluation method.

[0020] An evaluation method and an evaluation device according to an embodiment will be described below with reference to the drawings. In the following, the evaluation method and the evaluation device will be described using an example of evaluating chalk marks on textiles. In addition, in the following description, the same components will be assigned the same reference numerals and descriptions thereof will be omitted.

[0021] In this disclosure, the "substrate" may be a textile, leather, packaging paper, nonwoven fabric, etc. Typically, the substrate is a textile. The substrate to be evaluated has been treated with a repellent.

[0022] "Repellent" refers to a material that is applied to a substrate, typically the surface of the substrate, for the purpose of repelling water, oil, etc.

[0023] "Chalk marks" are lines that appear on the surface of a substrate due to rubbing against another object, etc. Chalk marks are used to evaluate the quality of substrates.

[0024] Evaluation Object and Friction Tester As described above, the present disclosure describes an example in which the substrate to be evaluated is a processed textile that has been treated with a repellent. Furthermore, the evaluation device 1, which will be described later with reference to FIG. 1, performs evaluation using chalk marks made on the textile. The chalk marks on the textile to be evaluated are made using a general friction tester, as will be described later.

[0025] Figure 2A shows an example in which three chalk marks M are placed near the center of a textile T. The spacing between the three chalk marks M is fixed, and their positions are also fixed. This makes it possible to accurately extract a first area A1 with chalk marks and a second area A2 without chalk marks, as shown in Figure 2B, and use these for evaluation.

[0026] Here, the first area A1 includes only the scratched area and does not include the area without scratches. That is, the first area A1 includes only the chalk mark area. Note that in FIG. 2B, for ease of understanding, the first area A1 is surrounded by a dashed line, including the area without chalk marks. Furthermore, the second area A2 includes only the area without scratches and does not include the scratched area. That is, the second area A2 includes only the area without chalk marks.

[0027] As shown in Figure 2B, the shape and size of the first range A1 and the second range may be different. Although not shown, the shape and size of the first range A1 and the second range may be the same. For example, when multiple chalk marks are added, multiple first ranges A11 to A13 may be set as shown in Figure 2C. While the example shown in Figures 2A and 2B shows an example in which three chalk marks are added, the number and method of adding the chalk marks are not limited.

[0028] Since the positions and sizes of the first range A1 and the second range are predetermined, the user can use the information of the first range A1 and the second range A2 at the timing of each evaluation without having to select a range from the image.

[0029] Friction Tester In the present disclosure, a friction tester can apply chalk marks to a textile by moving a terminal linearly over the textile treated with a repellent. The friction tester applies chalk marks at predetermined positions on the target textile. In this case, the target textile may be a textile of a predetermined size. Furthermore, the friction tester can apply chalk marks at predetermined positions on a textile of a predetermined size.

[0030] The friction tester applies chalk marks to the textile in a linear range of, for example, 10 mm or less in width. More specifically, the friction tester applies chalk marks to the textile in a linear range of 5 mm or less in width. If the width is large, the chalk marks will be far different in width from those that appear on general textiles. Therefore, the friction tester applies chalk marks of 10 mm or less, preferably 5 mm or less.

[0031] For example, the friction tester may move the terminal back and forth when moving the terminal over the textile. In this case, the friction tester preferably applies a chalk mark after the terminal has moved back and forth 10 times or less. For example, the number of times the terminal moves back and forth over the friction tester may be 3 or more and less than 5 times. Also, for example, the number of times the terminal moves back and forth over the friction tester may be 2 or more and less than 3 times. Furthermore, the number of times the terminal moves back and forth over the friction tester may be less than 2 times. Alternatively, the number of times the terminal moves back and forth over the friction tester may be less than 1 time. More preferably, the friction tester applies a chalk mark after the terminal has moved back and forth once in one direction. Moving the terminal over the textile multiple times may result in a thicker chalk mark. Furthermore, moving the terminal over the textile multiple times may result in multiple chalk marks being created.

[0032] For example, a friction tester applies a predetermined load to the terminal and moves the terminal linearly across the textile, which helps prevent variability when evaluating multiple subjects.

[0033] Specifically, the predetermined load may be in the range of 100 to 4000 g. More specifically, the predetermined load may be in the range of 1500 to 4000 g. This is because a large load may result in a chalk mark that is wider than that which occurs on general textiles. On the other hand, a small load may result in a chalk mark that is thinner than that which occurs on general textiles, making quantitative evaluation impossible.

[0034] The friction tester uses a terminal to make chalk marks at predetermined positions on the textile. For example, the friction tester makes a 30 mm long chalk mark on the center line of a 100 m x 100 m textile. The friction tester also makes two chalk marks 10 mm apart from the chalk marks and parallel to the chalk marks.

[0035] In this way, by applying chalk marks to the textile to be evaluated under predetermined conditions using a friction tester, it is possible to reduce the variability in the chalk marks applied to the textile, and therefore the variability in the evaluation results.

[0036] The friction tester is also called an abrasion tester or a friction and wear tester.

[0037] <<Coaxial Lighting>> Next, the lighting used when acquiring image data used in the evaluation device will be described. The evaluation device 1 (described later) shown in FIG. 1 uses image data of the surface of a substrate photographed by a photographing device 2. Here, the photographing device 2 preferably uses coaxial lighting to photograph the surface of the substrate. Coaxial lighting is lighting that irradiates light coaxially with the photographing axis (camera axis) of the photographing device, and may be lighting in which light emitted from a light source 31 is incorporated into the optical path of the lens 21 of the photographing device 2, as shown in an example in FIG. 3. Specifically, as shown in FIG. 3, coaxial lighting is lighting in which light from the light source 31 is reflected by a half mirror 32 and irradiated onto the evaluation object. In the present disclosure, as described above, the evaluation object is a textile T treated with a repellent agent. Here, a configuration including the light source 31 and half mirror 32 used for this coaxial lighting is referred to as a coaxial lighting device 3.

[0038] <Evaluation Device> Next, an evaluation device 1 according to an embodiment will be described with reference to Fig. 1. The evaluation device 1 has an arithmetic circuit and is an evaluation device for evaluating scratches on the surface of a substrate to be evaluated, wherein the evaluation device 1 acquires an image of the surface of the substrate, the arithmetic circuit 11 extracts a first area A1 containing scratches and a second area A2 without scratches from the image, calculates the difference between the luminance value of the first area A1 and the luminance value of the second area A2, and outputs an evaluation result based on the difference.

[0039] The evaluation device 1 is an information processing device including an arithmetic circuit 11, a storage device 12, and a communication circuit 13. The arithmetic circuit 11 is a controller that controls the entire evaluation device 1. For example, the arithmetic circuit 11 performs various processes related to evaluation by reading and executing an evaluation program P stored in the storage device 12. The arithmetic circuit 11 may also perform predetermined functions through the cooperation of hardware and software, or may be a hardware circuit designed specifically to perform predetermined functions. For example, the arithmetic circuit 11 may be realized by a CPU, an MPU, a GPU, an FPGA, a DSP, an ASIC, or the like.

[0040] The communication circuit 13 is an interface circuit (module) that enables data communication with an external device via the network 4. For example, the communication circuit 13 may execute data communication with the photographing device 2 that captures image data. The communication circuit 13 may also execute data communication with other external devices.

[0041] The evaluation device 1 may include an input device 14 and an output device 15. The input device 14 may be an operation button, a mouse, a keyboard, or the like used to input operation signals and data. The output device 15 may be a display or the like used to output processing results and data.

[0042] The storage device 12 is a recording medium for recording various information. The storage device 12 is realized, for example, by a RAM, a ROM, a flash memory, a solid-state drive (SSD), a hard disk, or other storage device, or by an appropriate combination thereof. The storage device 12 stores various data in addition to the evaluation program P executed by the arithmetic circuit 11. For example, the storage device 12 stores evaluation data 121, image data 122, result data 123, and the evaluation program P.

[0043] The evaluation data 121 is data used for evaluating textiles. For example, as shown in Fig. 4, the evaluation data 121 associates multiple evaluation levels with luminance ranges corresponding to each evaluation level. Here, the evaluation data 121 differs depending on the conditions of the substrate, etc., and therefore is preferably generated for each condition of the substrate, etc.

[0044] The image data 122 is image data obtained by photographing the textile to be evaluated. The image data may be a monochrome image (8-bit gray image). By creating a monochrome image, it becomes easier to compare the brightness values ​​of a first range A1 and a second range A2, which will be described later.

[0045] The result data 123 is data indicating the evaluation result of the textile obtained from the image data 122 .

[0046] The arithmetic circuit 11 acquires image data 122 from the photographing device 2. The image data 122 is an image of the surface of the textile to be evaluated. Chalk marks are made on the surface of the textile.

[0047] The arithmetic circuit 11 extracts a first area A1 with chalk marks and a second area A2 without chalk marks from the image data 122. As described above with reference to FIG. 2B , the size of the textile T to be evaluated is fixed. The positions of the chalk marks M affixed to the surface of the textile T are also fixed. Therefore, the positions of the first area A1 and the second area A2 can be identified based on the size and position.

[0048] The arithmetic circuit 11 calculates the luminance of the first range A1 as a first luminance value. The arithmetic circuit 11 also calculates the luminance of the second range A2 as a second luminance value. Specifically, the arithmetic circuit 11 calculates the average value of the luminance values ​​of each pixel in the first range A1 as the first luminance value. The arithmetic circuit 11 also calculates the average value of the luminance values ​​of each pixel in the second range A2 as the second luminance value.

[0049] The arithmetic circuit 11 calculates the difference between the first luminance value and the second luminance value.

[0050] 2C, when a plurality of first ranges A11 to A13 are set, for example, the arithmetic circuit 11 first calculates the difference between each of the first ranges A11 to A13 and the second range A2. Then, the arithmetic circuit 11 can set the average of the calculated differences A11 to A13 as the difference between the first luminance value and the second luminance value.

[0051] The arithmetic circuit 11 determines, as the evaluation result, the evaluation level corresponding to the range that includes the calculated difference in the evaluation data 121. The arithmetic circuit 11 also outputs the determined evaluation result to the output device 15.

[0052] Here, the evaluation device 1 may be realized by a single computer or a combination of multiple computers connected via a network. Although not shown, for example, all or part of the data stored in the storage device 12 may be stored in an external recording medium connected via a network, and the evaluation device 1 may be configured to use the data stored in the external recording medium.

[0053] <Evaluation Method> The evaluation method according to the embodiment is an evaluation method for evaluating scratches on the surface of a substrate to be evaluated, the evaluation method comprising the steps of: acquiring an image of the surface of the substrate to be evaluated; extracting a first area having scratches and a second area having no scratches from the image; calculating a difference between the brightness value of the first area and the brightness value of the second area; and obtaining an evaluation result based on the difference.

[0054] An evaluation method using the evaluation device 1 will be described below with reference to the flowchart shown in Fig. 5. Note that the flowchart shown in Fig. 5 includes a step of applying chalk marks to a textile using a friction tester and a step of photographing the textile before the series of evaluation steps performed by the evaluation device 1.

[0055] First, before the evaluation, a chalk mark is applied to the textile to be evaluated using a friction tester (S01). The chalk mark is applied under predetermined conditions.

[0056] Next, the photographing device 2 photographs the textile on which the chalk marks have been made in step S01 (S02).

[0057] When a chalk mark is made in step S01 and an image is taken in step S02, a series of processes related to evaluation are executed using the evaluation device 1.

[0058] The arithmetic circuit 11 acquires the image data 122 captured by the image capture device 2 in step S02 (S03). The arithmetic circuit 11 causes the storage device 12 to store the image data 122.

[0059] The arithmetic circuit 11 extracts a first area A1 with a chalk mark and a second area without a chalk mark from the image data 122 acquired in step S03 (S04). Since the positions and sizes of the first area A1 and the second area on the textile are predetermined, the arithmetic circuit 11 can use the information on the first area A1 and the second area A2 without requiring the user to perform operations from the image.

[0060] The arithmetic circuit 11 calculates a first luminance value and a second luminance value from the first range A1 and the second range A2 extracted in step S04, respectively (S05). Specifically, the arithmetic circuit 11 calculates the average of the luminance values ​​of each pixel in the first range A1 as the first luminance value. The arithmetic circuit 11 also calculates the average of the luminance values ​​of each pixel in the second range A2 as the second luminance value.

[0061] The arithmetic circuit 11 calculates the difference between the first luminance value and the second luminance value calculated in step S05 (S06). For example, in the case of light-colored fabric, conventional evaluations that utilize color changes in color images are difficult to understand. In contrast, evaluations based on luminance values ​​allow evaluations that are not affected by color. Therefore, using a monochrome image for the image data 122 makes it easier to understand the difference between the first luminance value and the second luminance value.

[0062] The arithmetic circuit 11 refers to the evaluation data 121 stored in the storage device 12, and determines an evaluation result according to the difference obtained in step S06 (S07).

[0063] The arithmetic circuit 11 outputs the evaluation result determined in step S07 (S08). For example, the arithmetic circuit 11 may output the evaluation result to the output device 15. Alternatively, for example, the arithmetic circuit 11 may output the evaluation result to an external device connected via the communication circuit 13.

[0064] In this way, the evaluation method and evaluation device according to the present disclosure evaluate the object using the luminance of the chalk mark, thereby making it possible to quantitatively evaluate the chalk mark by utilizing the correspondence between the predetermined luminance and the evaluation level.

[0065] Experimental Example: For example, a treated cloth treated with a repellent was used as the evaluation object. The treated cloth was nylon, polyester, or spandex fabric (referred to as spandex as necessary). The size of the treated cloth was 100 mm x 100 mm. The experimental conditions and results are shown in Tables 2.1 to 5.

[0066] Experimental Examples 1 to 13 are examples in which chalk marks were made using a friction tester. Table 2-1 shows the experimental results for repellent A. Table 2-2 shows the experimental results for repellent B and repellent C. Table 2-3 shows the experimental results for repellent D and repellent E.

[0067] A commonly used friction tester (product name: Friction Player FPR2200, manufactured by Rhesca Corporation) was used. A cylindrical probe (diameter 5 mm) was pressed against the surface of the processed fabric, and the surface was rubbed once. The friction load was 3000 g. The probe movement speed was 30 mm / s, and the movement distance was 30 mm. Using the friction tester, friction was performed on three points, spaced 10 mm apart, on one piece of processed fabric under the same conditions. In the table below, the first chalk mark is designated n1, the second chalk mark is designated n2, and the third chalk mark is designated n3.

[0068] The evaluation level, which is the result of the experimental example, is calculated using the brightness of each chalk mark. Specifically, the evaluation level is calculated using the evaluation data 121 described above with reference to FIG. 4. The evaluation data 121 used to calculate the evaluation level of the experimental result is shown in Table 1.

[0069] The visual evaluation of the chalk marks is indicated by the following values ​​of 1 to 5. Depending on the condition, intermediate values ​​(for example, 2-3, 3-4, 4-5, etc.) were used. 5: No trace is visible 4: Trace is barely visible 3: Trace is faintly visible 2: Trace is visible 1: Trace is slightly darkly visible

[0070]

[0071]

[0072]

[0073] Comparative Examples 1 to 4 are examples in which chalk marks were made with a person's fingernail. Table 3 shows the experimental results of Comparative Examples 1 to 4. Comparative Examples 1 and 2 are examples in which the same repellent A as in Experimental Examples 1 to 5 was used. Comparative Examples 3 and 4 are examples in which the same repellent B as in Experimental Examples 6 and 7 was used. When making chalk marks with a person's fingernail, the test cloth was placed on a flat surface and the surface of the test cloth was lightly scratched with a fingernail.

[0074]

[0075] Comparative Example 5 is an example in which the surface was rubbed 100 times using the friction tester used in Experimental Example 1. Other conditions were the same as those in Experimental Example 1. Table 4 shows the experimental results for Comparative Example 5.

[0076]

[0077] Comparative Examples 6 and 7 are examples in which the load was changed using the friction tester used in Experimental Example 1. Table 5 shows the experimental results of Comparative Examples 6 and 7. The load in Comparative Example 6 was 50 g. The load in Comparative Example 7 was 6000 g. Other conditions were the same as in Experimental Example 1.

[0078]

[0079] <Effects and Supplementary Information> As described above, the above embodiment has been described as an example of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made as appropriate.

[0080] The evaluation method and evaluation device according to all claims of the present disclosure are realized by hardware resources, such as a processor, a memory, and cooperation with a computer program.

[0081] The evaluation method and evaluation device of the present disclosure are useful for quantitatively evaluating the surface of a substrate.

[0082] This application claims priority based on Japanese Patent Application No. 2023-187049, filed on October 31, 2023, the entire contents of which are incorporated herein by reference.

[0083] REFERENCE SIGNS LIST 1 evaluation device 11 arithmetic circuit 12 storage device 13 communication circuit 14 input device 15 output device 121 evaluation data 122 image data 123 result data 2 imaging device 3 coaxial lighting device

Claims

1. A method for evaluating scratches on the surface of a substrate to be evaluated, comprising: acquiring an image of the surface of the substrate to be evaluated; extracting a first area having scratches and a second area having no scratches from the image; calculating the difference between the luminance value of the first area and the luminance value of the second area; and obtaining an evaluation result based on the difference.

2. The evaluation method according to claim 1, wherein, before obtaining the image, a terminal of a friction tester is moved back and forth on the surface of the substrate to be evaluated to scratch the surface of the substrate.

3. The evaluation method according to claim 1, wherein the substrate is a textile.

4. The evaluation method according to claim 3, wherein the scratch is a chalk mark on a textile.

5. The evaluation method according to claim 1, wherein the image is an image captured by a photographing device in which the optical axis of the light irradiated from a light source onto the base material is set coaxially with the photographing axis of the camera.

6. The evaluation method according to claim 2, wherein the friction tester scratches the evaluation object in a linear range of 10 mm or less in width.

7. The evaluation method according to claim 2, wherein the number of reciprocating movements of the terminal is 10 or less.

8. The evaluation method according to claim 2, wherein the friction tester causes a terminal to reciprocate at a predetermined load to scratch a surface of the substrate to be evaluated at a predetermined position on the surface.

9. The evaluation method according to claim 8, wherein the predetermined load is in the range of 100 g to 4000 g.

10. The evaluation method according to claim 8, wherein the predetermined load is in the range of 1500g to 4000g.

11. An evaluation device having an arithmetic circuit for evaluating scratches on the surface of a substrate to be evaluated, the evaluation device acquiring an image of the surface of the substrate, the arithmetic circuit extracting a first area having scratches and a second area having no scratches from the image, calculating the difference between the luminance value of the first area and the luminance value of the second area, and outputting an evaluation result based on the difference.

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