Device for inspecting base material, method for inspecting base material, and coating film removal device

Abstract

To provide a base material inspection device which can efficiently and accurately determine whether a water-soluble resin is on a surface of a base material formed of a non-water soluble resin.SOLUTION: A base material inspection device of the present invention is for determining whether a water-soluble resin is on a surface of a base material formed of a non-water soluble resin for inspection, and includes: a water droplet provision unit for providing a water droplet to the surface to inspect; a measurement unit for measuring the surface on which the water droplet has been provided; and a measurement unit for determining whether the water-soluble resin is on the surface on the basis of the result of measurement by the measurement unit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an inspection device and inspection method capable of efficiently and accurately inspecting whether or not a water-soluble resin is present on the surface of a substrate made of a water-insoluble resin, which is the subject of inspection, as well as a coating removal device having the above-mentioned inspection device. [Background technology]

[0002] In recent years, the increase in plastic waste has become an environmental problem, and efforts to reuse plastics have become more active. Plastics are used in various forms, and one of the methods for reusing these plastics is material recycling. In material recycling, plastic waste is generally separated by resin type, and each resin is remelted and molded into a new form for use.

[0003] In order to facilitate the process of separating resins, resin composites are known that function as composites of multiple types of resins while in use as products, and that allow the individual composite resin components to be separated after use.

[0004] In the above-mentioned resin composite, for example, a part of the constituent resins is a water-soluble resin, and the base material, the water-soluble resin, and other functional resins are laminated in this order, and after use, the composite is immersed in water to dissolve and remove the water-soluble resin, thereby separating the base material and the functional resin, and the composite can be recovered separately.

[0005] In the above-mentioned separation method, a method for inspecting whether the substrate and the functional resin have been reliably separated is, for example, to perform a chemical structure analysis on the surface of the substrate side after the substrate and functional resin have been separated, and to judge whether components derived from the functional resin are detected. For example, Patent Document 1 discloses a method using infrared spectroscopy. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2021-187869 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the testing method disclosed in Patent Document 1 requires that the test subjects be collected and then measured at a high concentration in order to improve testing accuracy. This has the problem that if the thickness of the water-soluble resin on the surface is thin, detection may not be possible or, even if detection is possible, the accuracy may be compromised.

[0008] In addition, since the measurement field of view is small, it is not easy to quickly inspect the entire surface of the object to be inspected, which is inefficient.

[0009] Therefore, the present invention provides an inspection device and inspection method capable of efficiently and accurately inspecting whether or not a water-soluble resin is present on the surface of an object to be inspected, as well as a coating removal device having the inspection device. [Means for solving the problem]

[0010] [1] The substrate inspection device of the present invention that solves the above problems is a device for inspecting whether or not a water-soluble resin is present on a surface of a substrate to be inspected that is made of a water-insoluble resin, a water droplet applying unit that applies water droplets to a surface of the object to be inspected; a measuring unit that measures the surface of the object to be inspected to which the water droplets have been applied; and and a determination unit that determines whether or not the water-soluble resin is present on the surface of the object to be inspected based on the measurement result of the measurement unit.

[0011] [2] The substrate inspection device according to [1] above is characterized in that the measurement unit performs a process of acquiring an image of the surface of the object to be inspected from directly above the surface, and a process of calculating an average diameter of water droplets adhering to the surface of the object to be inspected from the image; It is preferable that the determination unit performs a process of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the average diameter of the water droplets. [3] The substrate inspection device according to [1] above, wherein the measurement unit performs a process of acquiring an image of the surface of the object to be inspected from directly above the surface, and a process of calculating the roundness of water droplets adhering to the surface of the object to be inspected from the acquired image; It is preferable that the determination unit performs a process of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the circularity of the water droplet. [4] The substrate inspection device according to [1] above, wherein the measurement unit measures a haze value of a surface of the object to be inspected; It is preferable that the determination section performs a process of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the haze value.

[0012] [5] In the substrate inspection device according to [1] above, the measurement unit also measures the surface of the object to be inspected before the water droplets are applied, measuring a first haze value of the surface of the object to be inspected before the water droplets are applied, and measuring a second haze value of the surface of the object to be inspected to which the water droplets are applied; It is preferable that the determination unit performs a process of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. [6] The substrate inspection device according to [1] above includes an initial state measurement unit that measures the surface of the object to be inspected before the water droplets are applied; the initial state measuring unit measures a first haze value of a surface of the object to be inspected before the water droplets are applied; The measuring unit measures a second haze value of the surface of the object to be inspected to which the water droplets have been applied; It is preferable that the determination unit performs a process of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. [7] In the substrate inspection device of [5] or [6] above, it is preferable that the judgment unit performs a process of calculating a difference value or a ratio between the first haze value and the second haze value, and a process of judging whether or not the water-soluble resin is present on the surface of the object to be inspected based on the difference value or the ratio.

[0013] [8] In the substrate inspection device according to any one of [1] to [7] above, it is preferable that the water droplet applicator applies water droplets having an average particle size within a range of 1 to 500 μm. [9] In the substrate inspection device according to [8] above, it is preferable that the water droplet applying section applies water droplets with a particle size variation coefficient in the range of 0.005 to 0.050.

[0014]

[10] The coating removal device of the present invention is a device for removing a coating from a coated film having a coating containing a water-soluble resin on at least one surface of a substrate made of a water-insoluble resin, the device comprising: a conveying mechanism for conveying the coated film; a coating removal mechanism for removing the coating from the coated film; an inspection mechanism, located downstream of the coating removal mechanism in the conveying direction, for inspecting whether or not a coating containing the water-soluble resin remains on the base material; The inspection mechanism uses any one of the substrate inspection devices [1] to [9] above.

[0015]

[11] A method for inspecting a substrate of the present invention that solves the above-mentioned problems is a method for inspecting whether or not a water-soluble resin is present on a surface of a substrate to be inspected that is made of a water-insoluble resin, the method comprising the steps of: a water droplet application step of applying water droplets to the surface of the object to be inspected; a measuring step of measuring the surface of the object to be inspected to which the water droplets have been applied; and a determining step of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the measurement result in the measuring step.

[0016]

[12] The method for inspecting a substrate according to

[11] above further comprises the steps of: calculating an average diameter of water droplets adhering to the surface of the object to be inspected in the measuring step; It is preferable that in the determining step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the average diameter.

[13] The method for inspecting a substrate according to

[11] above further comprises calculating a circularity of a water droplet adhering to a surface of the object to be inspected in the measuring step; It is preferable that in the determining step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the circularity.

[14] The above-mentioned method for inspecting a substrate according to

[11] further comprises the steps of: measuring a haze value of a surface of the object to be inspected; It is preferable that in the determining step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the haze value.

[0017]

[15] The method for inspecting a substrate according to

[11] above further comprises, prior to the water droplet application step, an initial state measurement step of measuring a surface of the object to be inspected before the water droplet is applied; In the initial state measuring step, a first haze value of the surface of the object to be inspected before the water droplets are applied is measured; measuring a second haze value of the surface of the object to be inspected to which the water droplets are applied in the measuring step; It is preferable that in the determining step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value.

[16] In the substrate inspection method of

[15] above, it is preferable that in the determination step, a difference value or a ratio between the first haze value and the second haze value is calculated, and whether or not the water-soluble resin is present on the surface of the object to be inspected is determined based on the difference value or the ratio. Effect of the Invention

[0018] According to the substrate inspection device and substrate inspection method of the present invention, it is possible to efficiently and accurately inspect whether or not a water-soluble resin is present on the surface of a substrate to be inspected, which is made of a water-insoluble resin. [Brief description of the drawings]

[0019] [Figure 1] 1 is a schematic diagram of an inspection device according to an embodiment of the present invention; [Diagram 2] FIG. 4 is a schematic diagram of an inspection device according to another embodiment of the present invention. [Diagram 3] FIG. 4 is a schematic diagram of an inspection device according to another embodiment of the present invention. [Figure 4] 4 is a schematic diagram of a coating removal apparatus according to another embodiment of the present invention. [Diagram 5] 5 is a schematic diagram showing a method of determining the circularity in a determination step according to an embodiment of the present invention. FIG. [Figure 6] FIG. 13 is a schematic diagram of an inspection device used as a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The present inventors have conducted extensive research into a method for efficiently and accurately inspecting whether or not a water-soluble resin is present on the surface of an object to be inspected, and as a result have come up with the following inspection device and inspection method.

[0021] [Subject to inspection] In the present invention, a substrate made of a water-insoluble resin is the subject of inspection. The water-insoluble resin is not particularly limited as long as it is a resin that does not dissolve in water, but it is preferably a thermoplastic resin because it can be molded into various forms and used in a wide range of applications. Examples of thermoplastic resins include polyolefin resins, polystyrene resins, polyamide resins, polyimide resins, polyetherimide resins, polyester resins, polyarylene sulfide resins, polyarylene oxide resins, polysulfone resins, polyphenylsulfone resins, aromatic polyether ketone resins, acrylic resins, fluororesins, polyvinyl chloride resins, polyvinyl alcohol resins, polyvinylpyrrolidone resins, polyethylene oxide resins, polyvinyl acetate resins, and polyacetal resins, and may further be copolymers or modified products thereof.

[0022] It is preferable that the substrate is smooth at the portion to be inspected. "Smooth" refers to a surface having an arithmetic mean roughness Ra of 5 μm or less as measured in accordance with ISO 215178.

[0023] [Substrate inspection equipment] The substrate inspection device of the present invention is a device for inspecting whether or not a water-soluble resin is present on the surface of an object to be inspected. The water-soluble resin is not particularly limited as long as it is a resin that dissolves in water, and examples thereof include polyester resins, polyester urethane resins, polyacrylamide resins, ethylene ionomer resins, polyvinyl alcohol resins, polyvinylpyrrolidone resins, ethylene-vinyl alcohol resins, cellulose resins, and starch.

[0024] The inspection device of the present invention includes a water droplet applying unit that applies water droplets to the surface of the object to be inspected, a measurement unit that measures the surface of the object to which the water droplets have been applied, and a determination unit that determines whether or not a water-soluble resin is present on the surface of the object to be inspected based on the measurement results of the measurement unit. The present invention has discovered that, in determining whether or not a water-soluble resin is present on the surface of the object to be inspected, efficient and accurate inspection that was difficult to perform with conventional measurement methods is possible by applying water droplets to the surface of the object to be inspected and then measuring the points where the water droplets have been applied.

[0025] The mechanism for applying the water droplets of the water droplet applying unit may be any mechanism, for example, the water droplets may be applied in the form of droplets using a spray nozzle, or high pressure or high temperature water droplets may be applied using a high pressure washer or steam generator. Here, the water droplets may be any droplets that are made of a solvent that can dissolve the water-soluble resin, but in order to reduce the environmental load, it is preferable that the main component is water. In addition, additives such as surfactants may be appropriately contained within a range that does not impair the effects of the present invention.

[0026] The average particle size of the water droplets applied by the water droplet application unit is preferably within the range of 1 to 500 μm. If the average particle size of the water droplets is 500 μm or less, the water droplets are less likely to deform during application and are less likely to adhere to each other. As a result, the accuracy of the judgment is easily maintained even when the substrate is transported at high speed. If the average particle size of the water droplets is 1 μm or more, the water droplets applied to the substrate are less likely to evaporate and dissipate into the atmosphere, so the accuracy of the judgment is easily maintained.

[0027] It is more preferable that the coefficient of variation of the particle size of the water droplets is within the range of 0.005 to 0.050. The coefficient of variation is a value obtained by dividing the standard deviation of the particle size by the average particle size when the particle size distribution of the water droplets discharged from the nozzle is measured by a laser method. Here, the average particle size refers to the Sauter mean diameter. If the coefficient of variation is 0.050 or less, the shape of the water droplets applied and attached to the substrate tends to be uniform, and the accuracy of the judgment is easily maintained. The lower limit of the coefficient of variation is not particularly limited, but for water droplets applied by a spray nozzle method, the lower limit is substantially about 0.005.

[0028] In the inspection device of the present invention, the measurement unit preferably performs a process of acquiring an image of the surface of the object to be inspected to which water droplets have been applied, observed from directly above the surface, and a process of calculating the average diameter of the water droplets attached to the surface of the object to be inspected from the image, and the judgment unit preferably performs a process of judging whether or not a water-soluble resin is present on the surface of the object to be inspected based on the calculated average diameter of the water droplets. If a water-soluble resin is present on the surface of the object to be inspected, the water droplets will blend with the surface and spread more easily in the process of dissolving the water-soluble resin in the applied water droplets, and the average diameter of the water droplets observed from directly above the surface will be larger than when no water-soluble resin is present. Therefore, it can be judged that a water-soluble resin is present when the average diameter of the water droplets attached to the surface relative to the diameter of the water droplets discharged from the nozzle is equal to or greater than a specific value. Here, the average diameter means the circle equivalent diameter 17 of a certain water droplet as shown in FIG. 5, and is calculated by calculation as the diameter of a circle having an area equal to the area of ​​the water droplet.

[0029] In addition, the inspection device of the present invention is preferably configured such that the measurement unit acquires an image of the surface of the object to be inspected on which the water droplets are applied, observed from directly above the surface, and calculates the circularity of the water droplets attached to the surface of the object to be inspected from the image, and the judgment unit judges whether or not a water-soluble resin is present on the surface of the object to be inspected based on the calculated circularity of the water droplets. Here, the circularity is a value calculated by calculating the difference between the maximum radius 15 and the minimum radius 16 shown in FIG. 5 for a certain water droplet, and dividing the calculated difference by the circle equivalent diameter 17 of the water droplet. The smaller the circularity value, the closer the water droplet is to a perfect circle. When a water-soluble resin is present on the surface of the object to be inspected, the water droplets will spread out as they blend with the surface in the process of dissolving the water-soluble resin in the applied water droplets, but the way in which they spread out is not uniform within the surface but is anisotropic, so that the outer shape of the water droplets becomes disordered and the value of the circularity of the circle tends to increase. Therefore, when the circularity of the attached water droplets is equal to or greater than a specific value, it can be judged that a water-soluble resin is present.

[0030] The process of acquiring the image and the process of calculating the average diameter or circularity of the water droplets may be performed by one device or by separate devices. Even if they are performed by separate devices, the two devices are collectively regarded as a measurement unit.

[0031] In addition, the inspection device of the present invention preferably performs a process in which the measurement unit measures the haze value of the surface of the object to be inspected to which the water droplets are applied, and the judgment unit judges whether or not a water-soluble resin is present on the surface of the object to be inspected based on the measured haze value. When water droplets are attached to the surface of the object to be inspected, the haze value becomes larger than when no water droplets are attached because the attached water droplets scatter incident light. Furthermore, when a water-soluble resin is present on the surface of the object to be inspected, the water droplets become more likely to spread as they blend with the surface during the process of dissolving in the applied water droplets, and as a result, the three-dimensional shape of the water droplets changes from a shape close to a sphere to a flattened shape. The water droplets that have changed to a flattened shape and are attached to the surface have a smaller ability to scatter incident light than water droplets that are attached to the surface in a shape close to a sphere, so that the increase in the haze value due to the attachment of the water droplets tends to be suppressed. Therefore, it can be judged that a water-soluble resin is present when the haze value of the surface of the object to be inspected to which the water droplets are applied is equal to or less than a specific value.

[0032] In addition, it is also preferable that the inspection device of the present invention is one in which the measurement unit also measures the surface of the object to be inspected before the water droplets are applied, measures a first haze value of the surface of the object to be inspected before the water droplets are applied, measures a second haze value of the surface of the object to be inspected to which the water droplets are applied, and performs a process of judging whether or not a water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. More specifically, it is more preferable that the judgment unit performs a process of calculating a difference value or ratio between the first haze value and the second haze value, and judges whether or not a water-soluble resin is present on the surface of the object to be inspected based on the difference value or ratio. When water droplets are attached to the surface of the object to be inspected, the haze value becomes larger than when no water droplets are attached because the attached water droplets scatter the incident light. Also, when a water-soluble resin is present on the surface of the object to be inspected, the increase in the haze value due to the attachment of the water droplets tends to be suppressed as described above. Since the haze value is measured by a method of detecting light transmitted through the substrate, the haze value of the substrate itself and the increase in the haze value due to the attached water droplets are detected by adding them together. Therefore, by comparing the first haze value of the surface of the test object before the water droplets are applied with the second haze value of the surface of the test object to which the water droplets are applied, and making a judgment based on the difference or ratio between them, i.e., the change in the haze value due to the application of the water droplets, a more accurate judgment can be made than when making a judgment based only on the haze value after the water droplets are applied. In this case, it can be judged that a water-soluble resin is present when the value obtained by subtracting the first haze value from the second haze value or the value obtained by dividing the second haze value by the first haze value is equal to or less than a specific value.

[0033] It is also preferable that the inspection device of the present invention further comprises an initial state measurement unit that measures the surface of the object to be inspected before the water droplets are applied, the initial state measurement unit measures a first haze value of the surface of the object to be inspected before the water droplets are applied, the measurement unit measures a second haze value of the surface of the object to be inspected to which the water droplets have been applied, and the determination unit performs a process of determining whether or not a water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. By measuring the haze value with separate devices before and after the water droplets are applied, it is possible to determine online whether or not a water-soluble resin is present even for objects to be inspected that are being continuously transported.

[0034] The measurement unit, the initial measurement unit, and the determination unit may be included in one device, or may exist separately in multiple devices.

[0035] [Substrate inspection method] The substrate inspection method of the present invention includes a water droplet application step of applying water droplets to the surface of the object to be inspected, a measurement step of measuring the surface of the object to which the water droplets have been applied, and a determination step of determining whether or not a water-soluble resin is present on the surface of the object to be inspected based on the measurement results from the measurement step.

[0036] The method for applying water droplets in the water droplet application step may be any method. For example, water droplets may be applied in the form of droplets using a spray nozzle, or high-pressure or high-temperature water droplets may be applied using a high-pressure washer or a steam generator.

[0037] In the inspection method of the present invention, it is preferable that in the measurement step, the average diameter of water droplets adhering to the surface of the object to be inspected is calculated, and in the determination step, whether or not a water-soluble resin is present on the surface of the object to be inspected is determined based on the average diameter of the water droplets.

[0038] In addition, it is also preferable that the inspection method of the present invention calculates the circularity of a water droplet adhering to the surface of the object to be inspected in the measurement step, and judges whether or not a water-soluble resin is present on the surface of the object to be inspected based on the circularity in the judgment step.

[0039] It is also preferable that the inspection method of the present invention measures the haze value of the surface of the object to which water droplets have been applied in the measurement step, and determines whether or not a water-soluble resin is present on the surface of the object to be inspected based on the haze value in the determination step.

[0040] It is also preferable that the inspection method of the present invention further includes an initial state measurement step of measuring the surface of the object to be inspected before the water droplets are applied, the initial state measurement step measures a first haze value of the surface of the object to be inspected before the water droplets are applied, the measurement step measures a second haze value of the surface of the object to be inspected to which the water droplets are applied, and the determination step determines whether or not a water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. More specifically, it is more preferable that the determination step calculates a difference value or ratio between the first haze value and the second haze value, and determines whether or not a water-soluble resin is present on the surface of the object to be inspected based on the difference value or ratio.

[0041] When carrying out the inspection method of the present invention, the inspection device of the present invention can be suitably used, but it is not necessary to use the inspection device of the present invention. For example, when measuring the surface of the object to be inspected in the measurement step, the diameter of a water drop may be measured while visually observing the object to be inspected, without acquiring an image of the surface of the object to be inspected.

[0042] [Film removal device] The coating removal device of the present invention is a device for removing a coating from a coated film having a substrate made of a water-insoluble resin and a coating containing a water-soluble resin on at least one side of the substrate. The coating removal device of the present invention includes a transport mechanism for transporting the coated film, a coating removal mechanism for removing the coating from the coated film, and an inspection mechanism downstream of the coating removal mechanism in the transport direction for inspecting whether or not a coating containing a water-soluble resin remains on the substrate. The coating removal device of the present invention uses the inspection device described above for this inspection mechanism.

[0043] [Embodiments of the present invention] A preferred embodiment of the inspection device of the present invention will be described with reference to the drawings. Note that the following description is merely an example of one embodiment of the present invention, and the present invention is not limited to this embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0044] 1 is a schematic diagram of an inspection device 101 according to one embodiment of the present invention. The inspection device 101 includes a water droplet applying unit 2 that applies water droplets to the surface of a substrate 1 to be inspected, a measurement unit 3 that measures the surface of the substrate to which the water droplets have been applied, and a determination unit 4 that determines whether or not a water-soluble resin is present on the surface of the substrate based on the measurement results of the measurement unit 3.

[0045] The water droplet applying unit 2 of the inspection device 101 applies water droplets to a surface of the substrate 1 to be inspected for the presence of a water-soluble resin. The water droplet applying unit 2 may be any device capable of discharging water droplets 5 and applying the water droplets to the surface of the substrate, such as, but not limited to, a slit nozzle or a spray nozzle. The water droplets 5 are droplets of a liquid whose main component is water, and being the main component means that the ratio of the component exceeds 50%. The water droplets 5 discharged from the water droplet applying unit are preferably discharged by adjusting the aperture of the discharge unit so that the average particle diameter (D50, median diameter) is in the range of 1 to 500 μm. It is more preferable that the water droplets 5 are discharged by adjusting the coefficient of variation of the particle diameter to be 0.005 to 0.050. In addition, the water droplet applying unit 2 is provided with a discharge unit for discharging water droplets, a liquid delivery pump (not shown) for delivering the discharge liquid to the discharge unit, and a tank (not shown) for storing the discharge liquid.

[0046] The measuring unit 3 of the inspection device 101 is only required to measure the state of the surface of the substrate 1, and examples of the state of the surface include the shape and size of the water droplets adhering to the surface, and the haze of the substrate that changes with the adhering of the water droplets. When the measuring unit 3 measures the shape and size of the water droplets, an optical camera capable of quickly acquiring an image of the surface of the substrate 1 observed from directly above the surface is preferably used for the measuring unit 3. The average particle size of the water droplets, the coefficient of variation of the particle size, and the roundness are calculated by image analysis of the image acquired by the measuring unit 3. When the measuring unit 3 measures the haze of the substrate, it is preferable that the measuring unit 3 has an optical system capable of acquiring the haze value of the substrate 1 using transmitted light in the direction perpendicular to the surface. It is also preferable to measure the haze of the substrate before the water droplets are applied by the water droplet application unit 2 as well, and use the first haze value together with the second haze value, which is the haze value after the water droplets are applied, for the judgment of the judgment unit described later. In this case, it is preferable that the measurement range when measuring the first haze value and the measurement range when measuring the second haze value are the same.

[0047] The determination unit 4 of the inspection device 101 is only required to determine whether or not a water-soluble resin is present on the surface of the substrate 1 based on the measurement results of the measurement unit 3, and the determination is performed based on a determination criterion that is determined by setting a threshold value in advance. The determination is preferably performed automatically by computer processing.

[0048] The water droplet applying unit 2, the measurement unit 3, and the determination unit 4 of the inspection device 101 may be arranged in any manner as long as they do not interfere with each other's processing, but the processing procedure is performed in the order of the water droplet applying unit 2, the measurement unit 3, and the determination unit 4. However, only when measuring the haze value before and after the application of water droplets, the processing is performed in the order of the measurement unit 3, the water droplet applying unit 2, the measurement unit 3, and the determination unit 4.

[0049] Fig. 2 is a schematic diagram of an inspection device 201 according to another embodiment of the present invention. The inspection device 201 differs from the inspection device 101 in Fig. 1 in that the substrate 1 is transported in a constant direction a by a driving device (not shown), and in consideration of the steps of each process, the measurement unit 3 and the determination unit 4 of the inspection device 201 are located downstream of the water droplet application unit 2 in the transport direction.

[0050] FIG. 3 is a schematic diagram of an inspection device 301 according to yet another embodiment of the present invention. When the substrate 1 is transported, and the haze of the substrate before the water droplets are applied by the water droplet application unit 2 is measured as a first haze value, and the haze value after the water droplets are applied is used for judgment in the judgment unit 4 together with the second haze value, it is more preferable to configure the inspection device 301 as described above. In the inspection device 301 of FIG. 3, the measurement unit 6 is a part for measuring the first haze value, and the measurement unit 7 is a part for measuring the second haze value. Therefore, even if the substrate 1 is transported, both the first haze value before the water droplets are applied and the second haze value after the water droplets are applied can be measured. In this case, it is preferable to align the measurement ranges of the substrate measured by the measurement unit 6 and the measurement unit 7 so that they overlap on the same line in the transport direction of the substrate. In addition, if the substrate 1 is not being transported, the inspection device 101 of the embodiment in Figure 1 can also measure the first haze value of the substrate before water droplets are applied by the water droplet application unit 2 and the second haze value after the water droplets are applied, using a single measurement unit 3.

[0051] Fig. 4 is a schematic diagram of a coating removal apparatus 401 according to one embodiment of the present invention. The coating removal apparatus 401 is an apparatus for removing a coating 8 containing a water-soluble resin formed on the surface of a substrate 1 made of a water-insoluble resin from the substrate 1. The coating removal apparatus 401 includes a transport mechanism 9 for transporting the substrate 1 in a constant transport direction a, and a coating removal mechanism 10 for removing the coating. The coating removal apparatus 401 includes an inspection mechanism 11 downstream of the coating removal mechanism in the transport direction. The inspection mechanism 11 can be any of the inspection devices exemplified in the embodiments shown in Figs. 1 to 3.

[0052] It is preferable that the coating removal device 401 includes a mechanism for controlling the coating removal conditions of the coating removal mechanism 10 based on the inspection results of the inspection mechanism 11.

[0053] The substrate 1 in the coating removal device 401 is in the form of a film. The film may be in the form of cut sheets, but is preferably wound in a roll as shown in Fig. 4. By having the film in a roll form, coating removal can be performed continuously and efficiently.

[0054] The transport mechanism 9 in the coating removal apparatus 401 may be any means that moves the substrate 1 relative to the coating removal mechanism 10 and the inspection mechanism 11. The coating removal mechanism 10 and the inspection mechanism 11 may be fixed and the substrate 1 may be transported, or the coating removal mechanism 10 and the inspection mechanism 11 may move relative to the stationary substrate 1, or both may move in the same direction or in different directions.

[0055] As described above, by using the inspection device and inspection method of the present invention, as well as a coating removal device having the above-mentioned inspection device, it is possible to efficiently and accurately inspect whether or not water-soluble resin is present on the surface of an object to be inspected. EXAMPLES

[0056] The present invention will be described below with reference to examples, but the present invention is not necessarily limited thereto.

[0057] <Base material-1> A coating of polyvinyl alcohol resin (manufactured by Mitsubishi Chemical Corporation, "KL-05", saponification degree 80, average polymerization degree 500) as a water-soluble resin was formed to a thickness of 0.05 μm on one side of a roll-shaped polyethylene terephthalate film having a thickness of 30 μm and a width of 250 mm, to obtain substrate-1.

[0058] <Base material-2> A coating of polyvinyl alcohol resin (manufactured by Mitsubishi Chemical Corporation, "KL-05", saponification degree 80, average polymerization degree 500) as a water-soluble resin was formed to a thickness of 0.01 μm on one side of a roll-shaped polyethylene terephthalate film having a thickness of 30 μm and a width of 250 mm, to obtain substrate-2.

[0059] <Base material-3> A curable silicone resin coating was formed on the polyvinyl alcohol resin coating of the substrate-1 with reference to the coating material described in JP 2015-189226 A so as to have a thickness of 0.05 μm as follows. - Thermosetting silicone, manufactured by Shin-Etsu Chemical Co., Ltd., product name "KS-847T": 100 parts by weight, Platinum catalyst, manufactured by Shin-Etsu Chemical Co., Ltd., product name "CAT-PL-50T": 3 parts by weight, The resin was prepared by dissolving the resin in a mixed solution of toluene and MEK (mass ratio of toluene:MEK is 1:1) as a solvent so that the solid content was 1.8% by mass. The resin was then applied onto the polyvinyl alcohol resin coating using a bar coater and dried in an oven at 90°C for 20 seconds to form a coating of the release component, thereby obtaining substrate-3. The thermosetting silicone resin used in substrate-3 is a water-insoluble resin, but has high water vapor permeability. Therefore, when a thin film with a thickness of about 0.05 μm is laminated on top of a water-soluble resin layer, even if water droplets are applied from above the curable silicone resin, the water droplets are influenced by the water-soluble resin layer present in the lower layer and slightly blend into the surface of the curable silicone resin.

[0060] <Base material-4> A roll of polyethylene terephthalate film, 30 μm thick and 250 mm wide.

[0061] <Evaluation of the presence or absence of water-soluble resin on the substrate> The base material was cut into 1 cm square pieces for a total of 0.25 m 2 The extract was prepared in an amount of 100 mL, placed in an Erlenmeyer flask, and ultrasonic extraction (room temperature, 30 minutes) was performed after adding water (100 mL). The entire extract was freeze-dried, and the resulting dry residue was redissolved by adding 2 mL of water. A portion of the extract was then filtered through a PTFE filter (0.2 μm), after which a portion of the filtrate was subjected to LC / ELSD measurement under the following conditions. HPLC: LC-20A (Shimadzu Corporation) Column: ODS column ·Injection volume: 20μL Detection: Evaporative Light Scattering Detector (ELCD) Based on the calibration curve created by measuring a standard solution of polyvinyl alcohol (manufactured by Mitsubishi Chemical Corporation, "KL-05", saponification degree 80, average polymerization degree 500) with different concentrations under the same conditions, the amount of polyvinyl alcohol present on the substrate was quantified from the measurement results of the above substrate, and the amount of polyvinyl alcohol present on the substrate was quantified. 2When the amount was 0.5 mg / m or more, it was determined that a water-soluble resin was present on the substrate. 2 If the amount was less than 100%, it was determined that no water-soluble resin was present on the substrate. For the LC / ELSD measurement, the amount of polyvinyl alcohol present was measured a total of five times by changing the sample, and the presence or absence was determined based on the average value. When the type of water-soluble resin to be detected was other than polyvinyl alcohol or when multiple water-soluble resins were included, a calibration curve was prepared according to the composition of the water-soluble resin to be detected, and the presence or absence was evaluated in a similar manner.

[0062] <Evaluation of test accuracy> The results of the presence or absence of polyvinyl alcohol measured for each of Substrates-1 to -4 using the inspection method described in each Example and Comparative Example were collated with the results of the presence or absence of polyvinyl alcohol measured by the above EL / ELSD measurement, and evaluated according to the following criteria based on whether the judgment results matched. Note that the evaluation was performed for each speed by changing the conveying speed of the substrate in each Example and Comparative Example to 0 m / min (no conveying), 25 m / min, 50 m / min, and 100 m / min. A: The judgment results were consistent for all substrates. B: The judgment results were inconsistent for one substrate. C: The judgment results did not match for two or more substrates. D: Inspection was not possible using the inspection method described in each Example or Comparative Example.

[0063] <Example 1> An inspection device 201 shown in Fig. 2 was prepared, and the substrate was adjusted so as to be transported in the longitudinal direction relative to the fixed water drop application unit 2, measurement unit 3, and judgment unit 4. The substrate was transported while being given a tension of 20 N / m in the longitudinal direction to prevent slack in the substrate during transport.

[0064] In the water droplet application section 2, fine droplets of 25°C ion-exchanged water were continuously discharged from the spray nozzle, and the droplets were continuously applied onto the surface of the substrate. The fine droplets were generated by a two-fluid atomization method in which droplets are made fine by a high-speed airflow of compressed air, and the droplet size distribution was measured in advance by a laser method, and droplets were applied that were adjusted to have a Sauter mean diameter of 25 μm and a particle size variation coefficient of 0.040. When applying the droplets, the distance between the nozzle tip of the water droplet application section 2 and the substrate was 5 cm, and the amount of droplets applied was 1.0 m per unit area of ​​the substrate. 2 per 100cm 3 When the transport speed of the substrate was changed, the amount of water droplets applied per unit area was appropriately adjusted so that it was the same regardless of the transport speed.

[0065] A web appearance inspection device (product model: M9300) manufactured by Toshiba Digital Solutions Corporation was used for the measurement unit 3, and the substrate surface was observed from directly above the surface with a high-speed camera at a data rate of 320 Hz, pixel count of 4096, and a substrate width direction field of view of 300 mm, to obtain observation images. The distance between the spray nozzle of the water droplet application unit 2 and the detector of the measurement unit 3 in the substrate transport direction was set to 15 cm.

[0066] Furthermore, the measurement unit 3 utilized the defect classification function attached to the visual inspection device to obtain the individual circle equivalent diameters for all water droplets contained in the collected observation images.

[0067] In the judgment section 4, a continuous area of ​​0.25 m is measured in the measurement section. 2 The average of the equivalent circle diameters of all the water droplets observed on the surface of the substrate was calculated, and the presence or absence of a water-soluble resin on the surface of the substrate was judged according to the following criteria. [Judgment criteria] Present: Mean equivalent circle diameter is 30μm or more Absent: Mean equivalent circle diameter less than 30 μm.

[0068] When the substrate conveying speed was changed, it was possible to make a judgment at any speed, and it was confirmed that the evaluation of the inspection accuracy showed high accuracy, as shown in Table 1.

[0069] <Example 2> The same procedure as in Example 1 was carried out, except that the data acquired by the measuring unit and the judgment criteria of the judging unit were changed as follows.

[0070] The measurement unit 3 obtained the circularity of each water droplet included in the collected observation images.

[0071] In the judgment section 4, a continuous area of ​​0.25 m is measured in the measurement section. 2 The average value of the circularity was calculated for all the water droplets observed on the surface of the substrate, and the presence or absence of a water-soluble resin on the surface of the substrate was judged according to the following criteria. [Judgment criteria] Present: Average circularity of 0.1 or more Non-existent: Mean circularity value < 0.1.

[0072] When the substrate conveying speed was changed, it was possible to make a judgment at any speed, and it was confirmed that the evaluation of the inspection accuracy showed high accuracy, as shown in Table 1.

[0073] <Example 3> As in the first embodiment, an inspection device 201 shown in FIG. 2 was prepared.

[0074] In the water droplet application section 2, water droplets were continuously applied onto the surface of the substrate in the same manner as in Example 1.

[0075] For the measurement unit 3, an online haze monitor system (product model: HMS-3, 3-head type) manufactured by Murakami Color Research Laboratory Co., Ltd. was used, with three measurement heads installed at 5 cm intervals parallel to the width direction of the substrate, and haze measurements were performed using the transmission method with data acquisition intervals of 0.33 seconds to obtain the haze value. The distance between the spray nozzle of the water droplet application unit 2 and the detector of the measurement unit 3 in the substrate transport direction was 15 cm, and the amount of water droplets applied was 1.0 m per unit area of ​​the substrate. 2 per 100cm 3When the transport speed of the substrate was changed, the amount of water droplets applied per unit area was appropriately adjusted so that it was the same regardless of the transport speed.

[0076] In the judgment section 4, the average value of all the haze values ​​measured in the above-mentioned measuring section over a period of 5 seconds was calculated, and the presence or absence of a water-soluble resin on the surface of the substrate was judged according to the following criteria. [Judgment criteria] Present: Average haze value is 15% or less Absent: Average haze value is greater than 15%.

[0077] When the substrate conveying speed was changed, it was possible to make a judgment at any speed, but in the evaluation of the accuracy of the inspection, as shown in Table 1, it was confirmed that the accuracy was high when the conveying speed was 0 m / min, 25 m / min, and 50 m / min, but was slightly inferior at a conveying speed of 100 m / min. Specifically, the judgment results did not match for substrate-3.

[0078] <Example 4> An inspection device 301 shown in Fig. 3 was prepared, and the substrate was adjusted so as to be transported in the longitudinal direction relative to the fixed water drop applying unit 2, measuring units 6 and 7, and judgment unit 4. The substrate was transported while being given a tension of 20 N / m in the longitudinal direction to prevent slack in the substrate during transport.

[0079] In the water droplet application section 2, fine droplets of 25°C ion-exchanged water were continuously discharged from the spray nozzle, and the droplets were continuously applied onto the surface of the substrate. The fine droplets were generated by a two-fluid atomization method in which droplets are made fine by a high-speed airflow of compressed air, and the droplet size distribution was measured in advance by a laser method, and droplets were applied that were adjusted to have a Sauter mean diameter of 25 μm and a particle size variation coefficient of 0.040. When applying the droplets, the distance between the nozzle tip of the water droplet application section 2 and the substrate was 5 cm, and the amount of droplets applied was 1.0 m per unit area of ​​the substrate. 2 per 100cm 3When the transport speed of the substrate was changed, the amount of water droplets applied per unit area was appropriately adjusted so that it was the same regardless of the transport speed.

[0080] An online haze monitor system (product model: HMS-3, 3-head type) manufactured by Murakami Color Research Laboratory Co., Ltd. was used for the measurement unit 6, and three measurement heads were installed at 5 cm intervals parallel to the width direction of the substrate, and the haze value was obtained at data acquisition intervals of 0.33 seconds. The distance between the spray nozzle of the water droplet application unit 2 and the detector of the measurement unit 3 in the substrate transport direction was set to 15 cm.

[0081] The same online haze monitor system as in measurement unit 6 was used in measurement unit 7, and the installation conditions and measurement conditions were also the same as in measurement unit 6.

[0082] In the judgment unit 4, the average value of all the haze values ​​measured by the measurement unit 6 and the measurement unit 7 over a period of 5 seconds was calculated for each measurement unit, the average haze value of measurement unit 6 was designated as Hp, and the average haze value of measurement unit 7 was designated as Ha, and then the presence or absence of a water-soluble resin on the surface of the substrate was judged according to the following criteria: The installation positions and measurement times of measurement units 6 and 7 were adjusted so that the range of the substrate for which the haze value was measured was the same for each measurement unit. [Judgment criteria] Present: Ha-Hp is 10% or less Absent: Ha-Hp > 10%.

[0083] When the substrate conveying speed was changed, it was possible to make a judgment at any speed, and it was confirmed that the evaluation of the inspection accuracy showed high accuracy, as shown in Table 1.

[0084] <Example 5> The same procedure as in Example 4 was carried out, except that the judgment criterion in judgment unit 4 was changed to the ratio of Ha to Hp as follows. [Judgment criteria] Present: Ha / Hp ≤ 3 Absent: Ha / Hp > 3.

[0085] When the substrate conveying speed was changed, it was possible to make a judgment at any speed, and it was confirmed that the evaluation of the inspection accuracy showed high accuracy, as shown in Table 1.

[0086] <Example 6> Example 4 was repeated, except that the Sauter mean diameter of the water droplets applied to the water droplet application section 2 was adjusted to 600 μm and the coefficient of variation of the particle diameter was adjusted to 0.040.

[0087] When the substrate conveying speed was changed, it was possible to judge at any speed, but in the evaluation of the accuracy of the inspection, as shown in Table 1, it was confirmed that the accuracy was high when the conveying speed was 0 m / min and 25 m / min, but was slightly inferior at conveying speeds of 50 m / min and 100 m / min. Specifically, the judgment results for substrate-3 did not match at either the conveying speed of 50 m / min or 100 m / min.

[0088] <Example 7> The same procedure as in Example 4 was carried out except that the Sauter mean diameter of the water droplets applied to the water droplet application part 2 was adjusted to 25 μm and the coefficient of variation of the particle diameter was adjusted to 0.090.

[0089] When the substrate conveying speed was changed, it was possible to make a judgment at any speed, but in the evaluation of the accuracy of the inspection, as shown in Table 1, it was confirmed that the accuracy was high when the conveying speed was 0 m / min, 25 m / min, and 50 m / min, but was slightly inferior at a conveying speed of 100 m / min. Specifically, the judgment results did not match for substrate-3.

[0090] <Example 8> The substrate 3 was set in the coating removal device 401 shown in FIG. 4 from the upstream side of the transport mechanism 9, and the substrate film was transported at a transport speed of 50 m / min while being subjected to a tension of 20 N / m in the longitudinal direction.

[0091] In the coating removal mechanism 10, steam heated to 80°C is sprayed from a spray nozzle onto the coating surface with a surface area of ​​1 m 2 After one second, the coating was scraped off by pressing a stainless steel plate scraper against the coating surface.

[0092] The inspection mechanism 11, located downstream in the substrate transport direction as viewed from the coating removal mechanism 10, had the configuration of the inspection device 201 shown in Fig. 2 as in Example 1, the water droplets applied by the water droplet application unit were measured by the measurement unit, and the presence or absence of a water-soluble resin on the surface of the substrate was judged by the judgment unit. The conditions and judgment criteria of the inspection mechanism 11 were all the same as those of Example 1.

[0093] After passing through the coating removal mechanism 10, the substrate to be inspected was judged for the presence or absence of water-soluble resin using the method described above in <Evaluating the presence or absence of water-soluble resin on substrate>. The results were compared with those of the inspection mechanism 11, and it was confirmed that the results were the same, confirming that the judgment made by the inspection mechanism was accurate.

[0094] <Comparative Example 1> An inspection device 601 shown in Fig. 6 was prepared, and the substrate was adjusted so as to be transported in the longitudinal direction relative to a fixed measuring unit 3. The substrate was transported while being given a tension of 20 N / m in the longitudinal direction to prevent slack in the substrate during transport.

[0095] A portable-sized small FT-IR spectrometer (product model: FT-IR Rocket 2-12) manufactured by ARCoptix SA was used for the measurement unit 3, and IR measurements were made on the light transmitted through the substrate.

[0096] In the judgment section 4, an attempt was made to judge whether or not a water-soluble resin was present based on the presence of a spectral peak derived only from the water-soluble resin, but as shown in Table 1, it was difficult to distinguish between the peak and noise, and the accuracy of the judgment was low. Specifically, the judgment results did not match for substrate-2, substrate-3, and substrate-4. In addition, when the substrate moved, the spectral waveform became more distorted, making the judgment more difficult, and the accuracy of the judgment could not be evaluated.

[0097] The evaluation results of Examples 1 to 7 and Comparative Example 1 are summarized in Table 1.

[0098] [Table 1] [Industrial Applicability]

[0099] According to the present invention, it is possible to efficiently and accurately inspect whether or not a water-soluble resin is present on the surface of an object to be inspected. [Explanation of symbols]

[0100] 1 Base material 2 Water droplet application section 3. Measurement section 4 Judgment section 5 water drops 6. Measurement section (first haze value measurement) 7. Measurement section (second haze measurement) 8 Coating 9. Transport mechanism 10 Film removal mechanism 11 Inspection Organization 12. Outer shape of a water drop 13 Minimum circumscribed circle 14 Maximum inscribed circle 15 maximum radius 16 Minimum Radius 17 Equivalent circular diameter of a water drop a Substrate transport direction

Claims

1. An apparatus for inspecting whether or not a water-soluble resin is present on a surface of an inspection target of a substrate made of a water-insoluble resin, comprising: a water droplet applying unit that applies water droplets to a surface of the object to be inspected; a measurement unit that measures the surface of the object to be inspected to which the water droplets have been applied; a determination unit that determines whether the water-soluble resin is present on the surface of the object to be inspected based on the measurement result of the measurement unit; and An inspection device for a substrate comprising:

2. The measurement unit performs a process of acquiring an image of the surface of the object to be inspected from directly above the surface, and a process of calculating an average diameter of water droplets adhering to the surface of the object to be inspected from the image, the determination unit performs a process of determining whether the water-soluble resin is present on the surface of the inspection target based on the average diameter of the water droplets. The substrate inspection device of claim 1.

3. The measurement unit performs a process of acquiring an image of the surface of the object to be inspected from directly above the surface, and a process of calculating the circularity of water droplets adhering to the surface of the object to be inspected from the image, the determination unit performs a process of determining whether the water-soluble resin is present on the surface of the inspection target based on the circularity of the water droplet. The substrate inspection device of claim 1.

4. the measurement unit measures a haze value of a surface of the object to be inspected, the determination unit performs a process of determining whether the water-soluble resin is present on the surface of the object to be inspected based on the haze value. The substrate inspection device of claim 1.

5. The measurement unit, The surface of the test object before the water droplets are applied is also measured, measuring a first haze value of the surface of the test object before the water droplets are applied; measuring a second haze value of the surface of the test object to which the water droplets have been applied; the determination unit performs a process of determining whether the water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. The substrate inspection device of claim 1.

6. an initial state measuring unit that measures the surface of the object before the water droplets are applied; the initial state measuring unit measures a first haze value of a surface of the object to be inspected before the water droplets are applied; The measurement unit measures a second haze value of the surface of the object to be inspected to which the water droplets have been applied; and the determination unit performs a process of determining whether the water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value. The substrate inspection device of claim 1.

7. the determination unit performs a process of calculating a difference value or a ratio between the first haze value and the second haze value, and a process of determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the difference value or the ratio.

7. The substrate inspection device according to claim 5 or 6.

8. 2. The substrate inspection device according to claim 1, wherein the water droplet applying section applies water droplets having an average particle size within a range of 1 to 500 μm.

9. 9. The substrate inspection device according to claim 8, wherein the water droplet applying unit applies water droplets having a particle size variation coefficient in the range of 0.005 to 0.

050.

10. An apparatus for removing a coating from a coated film having a coating containing a water-soluble resin on at least one surface of a substrate made of a water-insoluble resin, the apparatus comprising: a conveying mechanism for conveying the coated film; a coating removal mechanism for removing the coating from the coated film; an inspection mechanism, located downstream of the coating removal mechanism in the conveying direction, for inspecting whether or not a coating containing the water-soluble resin remains on the base material; The inspection mechanism uses the substrate inspection device according to claim 1. Film removal device.

11. A method for inspecting whether or not a water-soluble resin is present on a surface of an inspection target of a substrate made of a water-insoluble resin, comprising the steps of: a water droplet application step of applying water droplets to a surface of the object to be inspected; a measuring step of measuring the surface of the object to be inspected to which the water droplets have been applied; a determination step of determining whether the water-soluble resin is present on the surface of the object to be inspected based on a measurement result in the measurement step; A method for inspecting a substrate comprising the steps of:

12. In the measuring step, an average diameter of water droplets adhering to the surface of the object to be inspected is calculated; In the determination step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the average diameter. The method for inspecting a substrate according to claim 11.

13. Calculating the circularity of the water droplet adhering to the surface of the object to be inspected in the measuring step; In the determination step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the circularity. The method for inspecting a substrate according to claim 11.

14. In the measurement step, a haze value of a surface of the object to be inspected is measured; In the determination step, it is determined whether or not the water-soluble resin is present on the surface of the object to be inspected based on the haze value. The method for inspecting a substrate according to claim 11.

15. an initial state measuring step of measuring a surface of the object before the water droplets are applied, before the water droplet applying step; In the initial state measuring step, a first haze value of a surface of the object to be inspected before the water droplets are applied is measured; In the measuring step, a second haze value of the surface of the object to be inspected on which the water droplets are applied is measured; in the determining step, determining whether or not the water-soluble resin is present on the surface of the object to be inspected based on the first haze value and the second haze value; The method for inspecting a substrate according to claim 11.

16. The method for inspecting a substrate according to claim 15, wherein in the determination step, a difference value or a ratio between the first haze value and the second haze value is calculated, and whether or not the water-soluble resin is present on the surface of the object to be inspected is determined based on the difference value or the ratio.

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