Coating equipment abnormality detection device

Abstract

To provide an abnormality detection device for a coating device capable of detecting adhesion of foreign matter to the surface of a substrate or deformation of the substrate. [Solution] An abnormality detection device 42 for a coating device 1 in which a substrate W having a conductive layer W2 formed on its surface is transported from upstream to downstream at a constant transport speed, and a conductive metal die 10 applies a conductive coating liquid to the substrate W to form a coated portion R. The abnormality detection device 42 has a contact terminal 44 that is located at the position where the die 10 applies the coating liquid or a position downstream of that position and that is in electrical contact with the conductive layer W2 exposed on the surface of the substrate W, a measurement unit 46 that measures the resistance value between the die 10 and the contact terminal 44, and a control unit 48 that stores the resistance value in chronological order as the substrate W is transported.

Description

[Technical Field]

[0001] The present invention relates to an abnormality detection device for a coating device that applies a coating liquid to a substrate, and more particularly to a coating device used for forming a perovskite film. [Background technology]

[0002] When manufacturing a perovskite film, a conductive layer is provided on a flexible film, and a coating liquid for forming perovskite is applied onto this conductive layer using a coating device.

[0003] In this case, the coating device carries the substrate consisting of the conductive layer and film by using a backup roll to hold it and run it, and ejects the coating liquid that forms the perovskite film from a die onto the substrate, coating the conductive layer of the substrate with the coating liquid at a constant coating thickness. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-50962 Summary of the Invention [Problem to be solved by the invention]

[0005] When coating is performed using the coating device described above, the substrate may be deformed by heat, or foreign matter may remain on the substrate surface due to poor cleanability. On the other hand, the formation of perovskite films is greatly influenced by the quality of the substrate, which serves as the base on which perovskite crystals grow. If the above-mentioned deformation or foreign matter remains, perovskite crystals cannot grow properly, making it difficult to achieve the desired power generation effect.

[0006] In view of the above problems, the present invention aims to provide an abnormality detection device for a coating device that can detect foreign matter adhering to the surface of a substrate or deformation of the substrate. [Means for solving the problem]

[0007] The present invention is an abnormality detection device for a coating device in which a substrate having a conductive layer formed on its surface is transported from upstream to downstream at a constant transport speed, and a conductive metal die applies a conductive coating liquid to the substrate to form a coated portion, characterized in that the abnormality detection device has a contact terminal located at a position where the die applies the coating liquid or downstream of that position, and which is in electrical contact with the conductive layer exposed on the surface of the substrate, a measurement unit that measures the resistance value between the die and the contact terminal, and a control unit that stores the resistance value in chronological order in accordance with the transport of the substrate. [Effects of the Invention]

[0008] According to the present invention, it is possible to detect the presence of foreign matter on the surface of the substrate or deformation of the substrate from a change in the resistance value between the die and the contact terminal. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an overall view of a coating device showing one embodiment of the present invention. [Figure 2] FIG. 2 is an enlarged longitudinal cross-sectional view of a main part of the die when the die is applying a coating liquid to a substrate. [Figure 3] This is also the surface of the substrate when the coating liquid is being applied. [Figure 4] FIG. 2 is an enlarged longitudinal cross-sectional view of a main part of the die when no coating liquid is being applied by the die. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an abnormality detection device 42 of a coating device 1 that applies a coating liquid to a long substrate W according to one embodiment of the present invention will be described with reference to the drawings.

[0011] The coating device 1 of this embodiment is used for producing a perovskite film, and applies a conductive coating liquid to the surface of a substrate W, which has a flexible and transparent film W1 on the surface of which a conductive layer W2 consisting of two layers, a transparent electrode layer and an electron transport layer, is formed. Note that the conductive layer W2 may have a two-layer structure in which a hole transport layer is laminated on a transparent electrode layer.

[0012] The conductive coating liquid is formed by dissolving perovskite in DMF and DMSO. "DMF" stands for dimethylformamide, an amide-based organic solvent that dissolves inorganic and organic compounds and is conductive. "DMSO" stands for dimethyl sulfoxide, an aprotic polar solvent that is insulating.

[0013] (1) Configuration of Coating Device 1 The configuration of the coating device 1 will be described with reference to FIG.

[0014] A backup roll 12 is disposed to the side of a die 10 that applies the coating liquid and is rotatable about a horizontal axis by a motor 18, and the substrate W is held by the left peripheral surface of this backup roll 12 and transported from bottom to top (i.e., from upstream to downstream) in Fig. 1. The transport speed V of this substrate W is determined by the rotation speed of the backup roll 12 and is, for example, 1 m / min to 20 m / min.

[0015] A pressure pump 14 is connected to the die 10, and the pressure pump 14 pressure-feeds the coating liquid from a tank 16 into the inside of the die 10. At this time, the amount of the coating liquid pressure-fed is determined by the number of rotations per unit time of the pressure pump 14.

[0016] (2) Configuration of die 10 Next, the configuration of the die 10 will be described with reference to FIGS.

[0017] The die 10 is made of a conductive metal. The main body 20 of the die 10 is composed of a first main body 22 and a second main body 24 disposed above the first main body 22. The length of the main body 20 in the left-right direction is set to be greater than the width of the substrate W, as shown in FIG.

[0018] The cross-sectional shape of the first body 22 is composed of a first lower surface consisting of a flat horizontal surface, a first upper surface consisting of a flat horizontal surface, and a first inclined surface formed by sloping from the front end of the first lower surface toward the front end of the first upper surface.

[0019] A liquid reservoir 26 is formed in the left-right direction on the first upper surface of the first main body 22. A supply path 28, through which the coating liquid is supplied, penetrates in the vertical direction through the center in the left-right direction of the liquid reservoir 26. The coating liquid is pressure-fed from the pressure pump 14 to the inlet of the supply path 28.

[0020] The cross-sectional shape of the second body 24 is composed of a second lower surface consisting of a flat horizontal surface, a second upper surface consisting of a flat horizontal surface, and a second inclined surface formed by sloping from the front end of the second upper surface toward the front end of the second lower surface.

[0021] A shim 30 made of a metal plate is sandwiched between the first upper surface of the first body 22 and the second lower surface of the second body 24. This shim 30 covers the lower part and both the left and right sides of the liquid reservoir 26, and is formed in a U-shape.

[0022] The first body 22, the shim 30, and the second body 24 are fixed together with bolts (not shown) to assemble the body 20. When the first body 22 and the second body 24 are fixed and the body 20 is assembled, the vertical cross section of the upper part of the body 20 of the die 10 is formed into an isosceles triangle shape consisting of a first inclined surface and a second inclined surface.

[0023] A first lip portion 34 protrudes forward from the front end of the first inclined surface of the first body 22. A second lip portion 36 protrudes forward from the front end of the second inclined portion of the second body 24. The first lip portion 34 and the second lip portion 36 form a lip 38 of the die 10. The lip 38 is called a lip because it has a lip-like shape that protrudes upward from the upper end of the body 20 of the die 10.

[0024] Between the first rear surface of the first body 22 and the second front surface of the second body 24, a horizontal space is formed above the liquid reservoir 26, forming a liquid passage 32. The front end of the liquid passage 32 reaches the front ends of the first lip portion 34 and the second lip portion 36, and a discharge port 40 extending in the left-right direction like a slit is formed in the front surface of the lip 38. The coating distance (gap) between the tip of the lip 38 and the surface of the substrate W (the surface of the conductive layer W2) is set to several tens of microns.

[0025] The coating device 1 uses a pressure pump 14 to send the coating liquid from a tank 16 to a supply path 28 of a die 10, and after the coating liquid accumulates in a liquid reservoir 26, the coating liquid is applied to a substrate W that is transported from an outlet 40 of a lip 38 via a liquid passage 32.

[0026] (3) Anomaly detection device 42 Next, an abnormality detection device 42 that detects whether or not there is an abnormality, such as foreign matter S adhering to the surface of the substrate W or the substrate W deforming due to heat and causing wrinkles, will be described with reference to Figures 2 to 4. This abnormality detection device 42 has a contact terminal 44, a measurement unit 46, and a control unit 48.

[0027] The contact terminals 44 are formed by brushes, and the bristles are conductive. The contact terminals 44 are attached at a height at which the bristles come into contact with the surface of the conductive layer W2 of the substrate W being transported by the backup roll 12, and are located to the side of the die 10 on the surface of the conductive layer W2 of the substrate W other than the coated portion R formed by the coating liquid (see FIGS. 2 and 3). The contact terminals 44 are located near the die 10, but may also be located a short distance away from the die 10 and downstream of the substrate W being transported from upstream to downstream (see FIG. 4).

[0028] The measuring unit 46 is, for example, a resistance meter, which measures the resistance between the conductive die 10 and the contact terminal 44. When measuring, a DC voltage is applied between the die 10 and the contact terminal 44, and the resistance is measured from the DC current flowing between them. In this case, the die 10 side is the positive electrode side, and the contact terminal 44 is the negative electrode side. However, the contact terminal 44 may also be the positive electrode side, and the die 10 may be the negative electrode side.

[0029] The control unit 48 stores the resistance values ​​measured by the measurement unit 46 in chronological order. Based on the resistance values ​​stored in chronological order, it determines whether or not there is an abnormality in the substrate W. This determination method will be explained next. The control unit 48 not only stores the resistance values ​​from the measurement unit 46 in chronological order, but also adjusts the rotation speed of the motor 18 to adjust the transport speed of the substrate W and adjusts the pumping amount of the pressure pump 14.

[0030] (4) How to detect abnormalities when coating fluid is applied by a die First, with reference to Figures 2 and 3, we will explain a method for detecting whether or not a foreign matter S has adhered to the surface of the substrate W when the coating liquid is being applied to the surface of the substrate W using the die 10 and the coating liquid is applied in that state.

[0031] The coating liquid is pressure-fed to the die 10 by a pressure pump 14, and is applied onto the substrate W, which is being transported by the die 10 at a constant transport speed, to form a coated area R with a constant coating thickness. In this case, both sides of the coated area R in the width direction are uncoated, and the conductive layer W2 of the substrate W is exposed. The contact terminal 44 is located at a position shifted in the width direction from the position of the lip 38 of the die 10 and is in contact with the exposed conductive layer W2 (see FIG. 3).

[0032] The measuring unit 46 passes a current to measure the resistance between the contact terminal 44 in contact with the conductive layer W2 and the die 10. In this case, since the conductive coating fluid is applied from the lip 38 of the die 10, the current passes through the measuring unit 46, the main body 20 of the die 10, the lip 38 of the die 10, the coated portion R formed by the conductive coating fluid, the conductive layer W2, the contact terminal 44, and returns to the measuring unit 46, measuring the resistance value at this time. The measuring unit 46 transmits the measured resistance values ​​to the control unit 48 in chronological order, and the control unit 48 stores the resistance values ​​in chronological order.

[0033] The control unit 48 stores a reference resistance value, which is the normal resistance range when there are no foreign matter S on the surface of the coating fluid or substrate W. When conductive or other foreign matter S is present in the coating area R, the control unit 48 detects an abnormality when the resistance value rises above the predetermined reference resistance value (when insulating foreign matter S is present) or falls below the predetermined reference resistance value (when conductive foreign matter S is present). The detection position is determined based on the conveyance time t from the initial position to the resistance value where the abnormality was detected and the conveyance speed v, for example, assuming that the coating start position on the substrate W is the initial position. For example, if an abnormal resistance value is detected after t = 30 seconds from the initial position, and the conveyance speed v is 1 m / min, the abnormality is determined to exist at a position 0.5 m (= v × t) from the initial position. The resistance values ​​measured by the measurement unit 46 include the resistance value of the metal die body 20 itself and the resistance value of the conductive layer W2 of the substrate W, and these resistance values ​​are also taken into consideration when determining the reference resistance value.

[0034] (5) Method for detecting abnormalities when the substrate W has wrinkles or other deformations A method for detecting abnormalities such as wrinkles or slack in the substrate W by transporting the substrate W preparatory to the coating of the coating liquid on the substrate W will be described with reference to Fig. 4. In this case, the distance between the lip 38 of the die 10 and the substrate W is set to the same coating interval as when the coating liquid is applied, for example, a distance of several tens of microns.

[0035] The substrate W is conveyed at a normal conveying speed v without the coating fluid being ejected from the die 10. The measuring unit 46 measures the resistance between the contact terminal 44 and the die 10 in a time series. Normally, there is a gap of several tens of microns between the die 10 and the substrate W, so the resistance is infinite, i.e., no current flows. However, when the substrate W deforms, wrinkles, slackens, or the like, and comes into contact with the lip 38 of the die 10 (see Figure 4), the resistance drops sharply. The control unit 48 measures the resistance in a time series, and if the resistance falls below a predetermined insulation resistance value, it determines that deformation such as wrinkles or slack has occurred in the substrate W. As described above, the conveying time t from the initial position where the substrate W began to be conveyed and the distance from the initial position are calculated using the conveying speed v to identify the abnormal location.

[0036] If deformation such as wrinkles or slack occurs in this substrate W, the conveying speed v may be slightly slow. Therefore, by adjusting the rotation of the motor 18 and increasing the conveying speed v, the deformation due to wrinkles or slack can be straightened out and the abnormality can be eliminated.

[0037] (6) Effects According to this embodiment, when a coating liquid is applied to a substrate W using a die 10, if a foreign matter S is mixed in the coated area R, the abnormal position can be identified from the resistance value.

[0038] Furthermore, when the substrate W is being transported without any coating liquid being applied in the preparation stage, if the substrate W comes into contact with the die 10 due to deformation such as wrinkles or sagging, the abnormal position can be identified by the resistance value.

[0039] Furthermore, the contact terminals 44 that come into contact with the conductive layer W2 of the substrate W are the conductive bristles of the brush, so that the conductive layer W2 is not damaged even when they come into contact with it, and reliable electrical contact can be achieved.

[0040] Furthermore, in this embodiment, abnormal positions of the substrate W on which the coating portion R is formed can be detected, thereby making it possible to improve the quality of the perovskite film, thereby improving the power generation efficiency of the perovskite solar cell and reducing the power generation using fossil fuels and the associated carbon dioxide emissions.

[0041] In the above embodiment, a coating device used for manufacturing a perovskite film was described, but this is not limited to this. The device can also be applied when applying a conductive coating liquid to a substrate W having a conductive layer W2 formed on its surface, and it can detect the presence of foreign matter S in the coating liquid or substrate W, or deformation of the substrate W.

[0042] In the above embodiment, the die 10 is disposed to the side of the backup roll 12, but the die 10 may be disposed obliquely downward, downward, or upward.

[0043] Although one embodiment of the present invention has been described above, this embodiment is presented by way of example and is not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0044] 1 Coating device, 10 Die, 12 Backup roll, 38 Lip, 40 Discharge port, 42 Abnormality detection device, 44 Contact terminal, 46 Measuring unit, 48 Control unit

Claims

1. An abnormality detection device for a coating device in which a substrate having a conductive layer formed on its surface is transported from upstream to downstream at a constant transport speed, and a conductive metal die applies a conductive coating liquid to the substrate to form a coated portion, The abnormality detection device a contact terminal located at a position where the coating liquid is applied by the die or downstream of the position, and in electrical contact with the conductive layer exposed on the surface of the substrate; a measuring unit for measuring a resistance value between the die and the contact terminal; a control unit that stores the resistance values ​​in chronological order in accordance with the transport of the base material; An abnormality detection device for a coating device, comprising:

2. the coating liquid is a conductive coating liquid that forms a perovskite film, The substrate has the conductive layer formed on a film. The abnormality detection device for a coating device according to claim 1.

3. The contact terminal is a brush having conductive bristles. The abnormality detection device for a coating device according to claim 1.

4. the control unit specifies a position in the transport direction of the base material at which the resistance value was measured, based on the time of the resistance value stored in chronological order and the transport speed. The abnormality detection device for a coating device according to claim 1.

5. When the coating liquid is applied to the substrate by the die to form the coated portion and then the substrate is transported, the contact terminal contacts the conductive layer at a position other than the coated portion; The control unit determines that foreign matter is present in the coated portion when the resistance value fluctuates above or below a predetermined reference resistance value. The abnormality detection device for a coating device according to claim 1.

6. When the coating liquid is conveyed to the substrate by the die without being coated thereon, the control unit determines that the conductive layer of the substrate is in contact with the die when the resistance value falls below a predetermined insulation resistance value. The abnormality detection device for a coating device according to claim 1.

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