Powder coating device

Abstract

This powder coating device is provided with: a powder supply unit for supplying a powder onto a surface of a base material; a squeegee which is arranged such that a gap is formed between the squeegee and the base material, adjusts the thickness of a powder layer comprising the powder supplied onto the surface of the base material by the powder supply unit, and is swept in a state in which an inclination angle of a surface in contact with the powder relative to a normal line direction of the surface of the base material can be changed; a powder inclination angle detector for detecting an angle between a surface of the powder layer and the base material; and a first control unit for adjusting the inclination angle of the surface of the squeegee that is in contact with the powder, on the basis of the inclination angle of the powder layer detected by the powder inclination angle detector.

Description

Technical Field

[0001] The present disclosure relates to a powder coating apparatus.

Background Art

[0002] Conventionally, a technique for coating a powder on the surface of a member while transporting the member such as a metal foil has been widely known.

[0003] For example, Patent Document 1 discloses a technique for coating a composite material (powder) containing an active material on the surface of a current collector that is a long metal foil.

[0004] Also, Patent Document 2 discloses a method of applying vibrations of about 700 Hz to a cylindrical squeegee in order to suppress the retention of powder.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

[0006] A powder coating apparatus according to an aspect of the present disclosure includes a powder supply unit that supplies powder onto the surface of a substrate, and is disposed so that a gap is formed between the powder supply unit and the substrate, and adjusts the thickness of a powder layer composed of the powder supplied onto the surface of the substrate by the powder supply unit, and scans in a state where an inclination angle of a surface in contact with the powder with respect to the normal direction of the surface of the substrate can be changed. A squeegee, a powder inclination angle detector that detects an angle between the surface of the powder layer and the substrate, and a first control unit that adjusts the inclination angle of the surface of the squeegee in contact with the powder based on the inclination angle of the powder layer detected by the powder inclination angle detector.

Brief Description of the Drawings

[0007]

Figure 1

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Figure 7A

Figure 7B

Figure 7C

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Figure 9

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BEST MODE FOR CARRYING OUT THE INVENTION

[0008] FIGS. 9 and 10 show schematic diagrams of the prior art using the blade-shaped squeegee 100 described in Patent Document 1.

[0009] Here, FIG. 9 shows a state immediately after the start when uniformly adjusting the thickness of a powder layer made of powder 4 by the blade-shaped squeegee 100, and FIG. 10 shows a state after a certain period of time.

[0010] Patent Document 1 describes that, as shown in FIG. 9, after supplying the powder 4 onto the surface of the metal foil as the substrate 3, the powder 4 is leveled by the blade-shaped squeegee 100 to uniformly adjust the thickness of the powder layer.

[0011] However, when the fluidity of the powder 4 is poor, as shown in FIG. 10, it is impossible to promote the entry of the powder 4 into the gap between the squeegee 100 and the substrate 3. The powder 4 stays on the upstream side in the relative movement direction 7 of the substrate 3 (metal foil) with respect to the squeegee 100 (the height of the powder accumulation 20 increases), and a bridge is generated between the squeegee 100 and the substrate 3 (metal foil). Therefore, it has been difficult to realize highly accurate continuous film formation.

[0012] FIGS. 11 to 14 show schematic diagrams of a conventional technique for vibrating a columnar squeegee 150 described in Patent Document 2.

[0013] Here, FIG. 11 shows the state immediately after the start (substantially at the start time) when adjusting the thickness of the powder layer composed of the powder 4 by vibrating the columnar squeegee 150 in the relative movement direction 7 of the substrate 3 with respect to the squeegee 150 and the reverse direction thereof (vibration direction A in FIG. 11) while maintaining the shortest distance 109 between the squeegee 150 and the substrate 3. FIG. 12 shows the state after a certain period of time has elapsed.

[0014] Further, FIG. 13 shows the state immediately after the start when adjusting the thickness of the powder layer composed of the powder 4 by vibrating the columnar squeegee 150 in a direction perpendicular to the relative movement direction 7 of the substrate 3 with respect to the squeegee 150 (vibration direction B in FIG. 13) while maintaining the shortest distance 109 between the squeegee 150 and the substrate 3. FIG. 14 shows the state after a certain time.

[0015] In Patent Document 2, as shown in FIGS. 11 to 12, after supplying the powder 4 onto the surface of the metal foil as the substrate 3, while adjusting the squeegee 150 so as to maintain the shortest distance 109 between the columnar squeegee 150 and the substrate 3, it is described that the thickness of the powder layer is uniformly adjusted by vibrating in the relative movement direction 7 of the substrate 3 with respect to the squeegee 150 and the reverse direction thereof (vibration direction A in FIG. 11) to level it.

[0016] However, when the fluidity of the powder 4 is poor, as shown in Fig. 12, it is impossible to promote the entry of the powder 4 into the gap between the squeegee 150 and the base material 3, and the powder 4 stays on the upstream side in the relative movement direction 7 of the base material 3 (metal foil) with respect to the squeegee 150 (the height of the powder accumulation 20 increases), and a bridge is generated between the squeegee 150 and the base material 3 (metal foil), so it has been difficult to realize highly accurate continuous film formation.

[0017] Further, in Patent Document 2, as shown in Figs. 13 to 14, after supplying the powder 4 onto the surface of the metal foil as the base material 3, while maintaining the shortest distance 109 between the columnar squeegee 150 and the base material 3, the squeegee 150 is vibrated in a direction perpendicular to the relative movement direction 7 of the base material 3 with respect to the squeegee 150 (the vibration direction B in Fig. 13) to level it, thereby adjusting the thickness of the powder layer uniformly.

[0018] However, when the fluidity of the powder 4 is poor, as shown in Fig. 14, it is impossible to promote the entry of the powder 4 into the gap between the squeegee 150 and the base material 3, and the powder 4 stays on the upstream side in the relative movement direction 7 of the base material 3 (metal foil) with respect to the squeegee 150 (the height of the powder accumulation 20 increases), and a bridge is generated between the squeegee 150 and the base material 3 (metal foil), so it has been difficult to realize highly accurate continuous film formation.

[0019] In recent years, in a situation where the demand for both further high performance and low cost of devices has been increasing, for example, there is a need for a technology to directly and precisely form a film of the powder 4 of a functional powder material that is much smaller than before, such as having a particle size in the range of several tens of μm to sub-μm, is prone to aggregation, and has low fluidity, without going through processes such as granulation. However, in the conventional technology, the effect of suppressing the retention and bridge formation of the powder 4 with a small particle size, prone to aggregation, and low fluidity is not sufficient, and it is difficult to level the powder layer so that the thickness of the powder layer becomes uniform.

[0020] Therefore, an object of the present disclosure is to provide a powder coating apparatus capable of forming a powder layer with little film thickness variation on the surface of the base material 3.

[0021] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0022] Note that each of the embodiments described below shows comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, order of steps, etc. shown in the following embodiments are merely examples and are not intended to limit the present disclosure. In addition, among the components in the following embodiments, components not described in the independent claims are described as optional components.

[0023] Also, each figure is a schematic diagram and is not necessarily drawn precisely. Also, in each figure, the same constituent members are denoted by the same reference numerals.

[0024] Also, embodiments will be described below with reference to the drawings as appropriate, but detailed descriptions may be omitted more than necessary. For example, detailed descriptions of well-known matters and redundant descriptions of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate the understanding of those skilled in the art.

[0025] (Embodiment 1) FIG. 1 is a schematic diagram of a powder coating apparatus 1 which is an embodiment of the present disclosure.

[0026] As shown in Fig. 1, the powder coating apparatus 1 of the present disclosure includes a powder supply unit 5 that supplies powder 4 onto the surface of a substrate 3, and is arranged such that a gap is formed between the substrate 3. The squeegee 2 scans while being able to change the inclination angle 6 of the surface 10 in contact with the powder 4 to adjust the thickness of the powder layer composed of the powder 4 supplied onto the surface of the substrate 3 by the powder supply unit 5. A drive unit (not shown) relatively moves the substrate 3 and the squeegee 2 in a certain direction. With respect to the powder supply position 22, at the upstream side in the relative movement direction 7 of the substrate 3 with respect to the squeegee 2, the powder inclination angle detector 11 detects the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the substrate 3 and the substrate 3. Based on the inclination angle of the powder layer detected by the powder inclination angle detector 11, a first control unit 12 is provided to adjust the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 with respect to the normal direction of the surface of the substrate 3. Here, coming into contact with the powder 4 includes cases where at least a part of the surface 10 of the squeegee 2 is in contact with or substantially in contact with the powder 4.

[0027] The powder 4 may be any powdery substance. For example, in the present embodiment, as the powder 4, a particle group containing an active substance with an average particle diameter (D50) of 0.005 μm or more and 50 μm or less can be used. The average particle diameter (D50) is the volume-based median diameter calculated from the measurement values of the particle size distribution by the laser diffraction / scattering method, and can be measured using a commercially available laser analysis / scattering type particle size distribution measuring device.

[0028] The powder inclination angle detector 11 is disposed on at least one of the upstream side or the downstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2 with respect to the powder supply position 22, and detects the angle 8 between the surface of the powder layer formed by the powder 4 supplied to the base material 3 and the base material 3. In the present embodiment, the powder inclination angle detector 11 is disposed on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2 with respect to the powder supply position 22. Note that the powder inclination angle detector 11 only needs to be able to detect the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3. The powder inclination angle detector 11 may, for example, be photographed by a camera (not shown) from a direction perpendicular to the relative movement direction 7 of the base material 3 (the front side of the paper of FIG. 1), and the position of the surface of the powder layer formed by the powder 4 supplied on the base material 3 may be captured by image processing such as binarization processing, and the angle 8 between the surface of the powder layer formed by the powder 4 supplied on the base material 3 and the base material 3 may be detected. Further, the powder inclination angle detector 11 may photograph the shadow of the powder 4 supplied on the base material 3 lifted by a light source by a camera, capture the position of the surface of the powder layer formed by the powder 4 supplied on the base material 3 by image processing such as binarization processing, and detect the angle 8 between the surface of the powder layer formed by the powder 4 supplied on the base material 3 and the base material 3. Here, the angle 8 between the surface of the powder layer formed by the powder 4 supplied on the base material 3 and the base material 3 is, for example, a right angle or an acute angle between the surface of the base material 3 and the surface of the powder layer at the boundary portion between the powder layer and the base material 3.

[0029] Here, for example, in the case of very fine powder 4 with a particle size in the range of several tens of μm to sub-μm, when it is in a static state, aggregation progresses, and the fluidity of the powder 4 is promoted to decrease. In such a situation, generally, before the powder 4 is introduced into the powder coating apparatus 1, the material properties such as the angle of repose of the powder 4 are measured to confirm the fluidity of the powder 4 in advance. Then, after confirming that the measured value is within a predetermined range, the powder 4 is introduced into the powder coating apparatus 1. However, in the actual production process, production continues while repeatedly starting and stopping coating at least to some extent, or due to equipment troubles or the like, after a certain period of stoppage during production, coating is started again. In such a situation, at the time of coating stoppage, the powder 4 introduced into the powder coating apparatus 1 becomes static in the interior of the powder supply section 5 and in the piping path leading to the powder supply section 5 (not shown), and aggregation may progress, promoting a decrease in the fluidity of the powder 4.

[0030] As a result, when leveling with the squeegee 2 to form a powder layer with little film thickness variation, the fluidity of the powder 4 in the state supplied onto the substrate 3 differs from that just before leveling with the squeegee 2 and the time when it was confirmed before being introduced into the powder coating apparatus 1.

[0031] Here, in the prior art, the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4) that affect the film thickness variation of the powder layer after treatment are set based on the fluidity confirmed before being introduced into the powder coating apparatus 1. For this reason, after the powder 4 is introduced into the powder coating apparatus 1, if aggregation of the powder 4 progresses and the fluidity changes in the interior of the powder supply section 5 and in the piping path leading to the powder supply section 5 (not shown), it becomes difficult to perform precise coating continuously with little stable film thickness variation.

[0032] On the other hand, in the powder coating apparatus 1 according to an embodiment of the present disclosure, an angle 8 between the surface of the powder layer formed by the powder 4 and the substrate 3 is detected by a powder inclination angle detector 11 on the upstream side in the relative movement direction 7 of the substrate 3 with respect to the squeegee 2 with respect to the powder supply position 22, and a first control unit 12 for adjusting the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is provided. For this reason, in the powder coating apparatus 1, when leveling with the squeegee 2 to form a powder layer with less film thickness variation, the fluidity of the powder 4 in the state supplied on the substrate 3 immediately before leveling with the squeegee 2 is grasped, and based on this, the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4) can be set. In addition, even when the fluidity of the powder 4 changes during continuous production, the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4) can be adjusted according to the change.

[0033] Here, it is particularly desirable that the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 be an angle equal to or greater than the angle 8 between the surface of the powder layer formed by the powder 4 and the substrate 3 on the upstream side in the relative movement direction 7 of the substrate 3 with respect to the powder supply position 22, detected by the powder inclination angle detector 11.

[0034] FIGS. 7A to 7C show the relationship between the angle of repose of the powder 4 and the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4.

[0035] Here, FIG. 7A shows the case where the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is 0°, FIG. 7B shows the case where the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is greater than 0° and smaller than the angle of repose of the powder 4, and FIG. 7C is a diagram showing the case where the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is greater than the angle of repose of the powder 4.

[0036] As shown in FIG. 7A, the angle of repose A is the angle between the slope of the mountain of the powder 4 formed when the powder 4 is dropped from a certain height onto, for example, a substrate and the powder 4 maintains stability in a mountain shape without spontaneously collapsing and the horizontal plane.

[0037] Here, when leveling the powder layer composed of the powder 4 supplied onto the base material 3 with the squeegee 2, since the powder 4 is conveyed in the relative movement direction 7 of the base material 3, it is considered that the upstream side in the relative movement direction 7 of the base material 3 is the upper side and the downstream side is the lower side, and the behavior is equivalent to dropping the powder 4 from above toward the surface 10 of the squeegee 2 in contact with the powder 4.

[0038] As a result, when the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is 0°, as shown in Fig. 7A, when the angle of repose of the powder 4 is A, the powder 4 reaching the surface 10 of the squeegee 2 in contact with the powder 4 is less likely to collapse, and the powder 4 is likely to stay.

[0039] Also, when the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is greater than 0° and less than the angle of repose A of the powder 4, as shown in Fig. 7B, the powder 4 reaching the surface 10 of the squeegee 2 in contact with the powder 4 is promoted to enter the gap between the squeegee 2 and the base material 3 due to the inclination of the surface 10 of the squeegee 2 in contact with the powder 4, so the retention of the powder 4 can be suppressed.

[0040] Also, when the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 is greater than the angle of repose A of the powder 4, as shown in Fig. 7C, since the force for the powder 4 reaching the surface 10 of the squeegee 2 in contact with the powder 4 to stay on the surface 10 of the squeegee 2 in contact with the powder 4 can be made very small, a very large effect of promoting the powder 4 to enter the gap between the squeegee 2 and the base material 3 is obtained, so a very large effect of suppressing the retention of the powder 4 can be obtained.

[0041] Here, the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the substrate 3 and the substrate 3 on the upstream side in the relative movement direction 7 of the substrate 3 with respect to the powder supply position 22 detected by the powder inclination angle detector 11 means the angle of repose of the powder 4 in the state supplied onto the substrate 3 and serves as an index representing the fluidity of the powder 4. From this, while the powder coating apparatus 1 continues production, it grasps the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the substrate 3 and the substrate 3 on the upstream side in the relative movement direction 7 of the substrate 3 with respect to the powder supply position 22, and accordingly adjusts the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4. In particular, in the powder coating apparatus 1, by setting the angle to be equal to or greater than the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the substrate 3 and the substrate 3 on the upstream side in the relative movement direction 7 of the substrate 3 with respect to the powder supply position 22, a very large effect of suppressing the retention of the powder 4 can be obtained, enabling precise coating with continuously stable film thickness variation and little variation.

[0042] (Embodiment 2) FIG. 2 is a schematic view of a powder coating apparatus 1 according to an embodiment of the present disclosure.

[0043] The powder inclination angle detector 11 of the powder coating apparatus 1 of the present disclosure is disposed on the downstream side in the relative movement direction 7 of the substrate 3 with respect to the squeegee 2 with respect to the powder supply position 22. The powder coating apparatus 1 detects, with the powder inclination angle detector 11, the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the substrate 3 and the substrate 3 on the downstream side in the relative movement direction 7 of the substrate 3 with respect to the squeegee 2 with respect to the powder supply position 22, and is basically the same in configuration as that of Embodiment 1 except that it includes a first control unit 12 that adjusts the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4. Therefore, the description of the basic configuration of the powder coating apparatus 1 in the present embodiment will be appropriately omitted.

[0044] Here, the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22 detected by the powder inclination angle detector 11 means the angle of repose of the powder 4 in the state of being supplied onto the base material 3, and serves as an index representing the fluidity of the powder 4. From this, while the powder coating apparatus 1 continues production, it grasps the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, and accordingly adjusts the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4. In particular, in the powder coating apparatus 1, by making the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22 equal to or greater than the angle 9, a very large effect of suppressing the retention of the powder 4 can be obtained, and continuous and stable precise coating with little film thickness variation becomes possible.

[0045] (Embodiment 3) FIG. 3 is a schematic diagram showing a powder coating apparatus 1 which is an embodiment of the present disclosure.

[0046] The powder coating apparatus 1 of the present disclosure is based on the powder accumulation height 20 detected by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the squeegee 2, and a second control unit 13 that adjusts the powder supply amount to the base material 3, and a powder accumulation height detector 23 that detects the height of the powder accumulation on the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the squeegee 2. Since it is basically the same as the configuration in Embodiment 1 except for this, the description of the basic configuration of the powder coating apparatus 1 in this embodiment will be omitted as appropriate.

[0047] Here, the powder accumulation height detector 23 may be any device that can detect the powder accumulation height 20 on the surface 10 of the squeegee 2 that comes into contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3. For example, the powder accumulation height detector 23 may take a photograph with a camera from a direction perpendicular to the relative movement direction 7 of the base material 3 (the near side of the paper surface in FIG. 3), and capture the position of the surface of the powder accumulation 24 through image processing such as binarization processing, and detect the powder accumulation height 20 on the surface 10 of the squeegee 2 that comes into contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3. Further, the powder accumulation height detector 23 may take a photograph with a camera of the shadow of the powder accumulation 24 on the surface 10 of the squeegee 2 that comes into contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3, which is lifted by a light source, and capture the position of the surface of the powder accumulation 24 through image processing such as binarization processing, and detect the powder accumulation height 20 on the surface 10 of the squeegee 2 that comes into contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3.

[0048] Here, it is desirable that the ratio Z between the powder accumulation height 20 (denoted as A in the following formula) and the gap distance 21 between the base material 3 and the squeegee 2 (denoted as B in the following formula) is greater than 1 and equal to or less than 3. The ratio Z is defined by Z = A / B.

[0049] If Z is greater than 1 and equal to or less than 3, the force applied from the squeegee 2 to the powder 4 can be reduced, so that aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed.

[0050] When the powder accumulation height 20 such that Z exceeds 3 becomes excessively large, the force applied from the squeegee 2 to the powder 4 becomes too large, so that aggregation and retention of the powder 4 are likely to occur, and powder clogging is likely to occur. Further, when Z is 1 or less, the flattening effect cannot be obtained.

[0051] As described above, while grasping the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the powder coating apparatus 1 adjusts the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 accordingly. In addition, on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2, the powder accumulation height 20 is detected by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4, and the powder supply amount to the base material 3 is adjusted. In particular, in the powder coating apparatus 1, by setting the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the base material 3 and the squeegee 2 to be greater than 1 and equal to or less than 3, in the powder coating apparatus 1, aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed. Therefore, continuous and stable precision coating with little film thickness variation becomes possible.

[0052] (Embodiment 4) FIG. 4 is a schematic diagram showing a powder coating apparatus 1 according to an embodiment of the present disclosure.

[0053] The powder coating apparatus 1 of the present disclosure is basically the same in configuration as that of Embodiment 2, except that it includes a second control unit 13 that detects the powder accumulation height 20 by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2 and adjusts the powder supply amount to the base material 3. Therefore, the description of the basic configuration of the powder coating apparatus 1 in this embodiment will be omitted as appropriate.

[0054] Here, the powder accumulation height detector 23 may be any device that can detect the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3. For example, the powder accumulation height detector 23 may take a photograph with a camera from a direction perpendicular to the relative movement direction 7 of the base material 3 (the side closer to the viewer in the plane of FIG. 4), and capture the position of the surface of the powder accumulation 24 through image processing such as binarization processing, so as to detect the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3. Alternatively, the powder accumulation height detector 23 may take a photograph with a camera of the shadow of the powder accumulation 24 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3, which is lifted by a light source, and capture the position of the surface of the powder accumulation 24 through image processing such as binarization processing, so as to detect the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3.

[0055] Here, it is desirable that the ratio Z of the powder accumulation height 20 to the gap distance 21 between the base material 3 and the squeegee 2 is greater than 1 and equal to or less than 3.

[0056] If Z is greater than 1 and equal to or less than 3, the force applied from the squeegee 2 to the powder 4 can be reduced, so that aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed. When the powder accumulation height 20 is in a state where Z exceeds 3 and becomes excessively large, the force applied from the squeegee 2 to the powder 4 becomes too large, so that aggregation and retention of the powder 4 are likely to occur, and powder clogging is likely to occur. Also, when Z is 1 or less, the flattening effect cannot be obtained.

[0057] In this way, while grasping the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, in addition to adjusting the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 accordingly, the powder accumulation height 20 is detected by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2, and the powder supply amount to the base material 3 is adjusted. In particular, in the powder coating apparatus 1, by setting the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the base material 3 and the squeegee 2 to be greater than 1 and less than or equal to 3, aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed. Therefore, continuous and precise coating with stable film thickness variation can be achieved.

[0058] (Embodiment 5) FIG. 5 is a schematic diagram showing a powder coating apparatus 1 according to an embodiment of the present disclosure.

[0059] The powder coating apparatus 1 of the present disclosure is basically the same as that of Embodiment 3 except that it includes a third control unit 14 that detects the powder accumulation height 20 by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2 and adjusts the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4. Therefore, the basic configuration of the powder coating apparatus 1 in this embodiment will be omitted from the appropriate description.

[0060] The powder coating apparatus 1 detects the powder accumulation height 20 at the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side of the relative movement direction 7 of the substrate 3 with respect to the squeegee 2 by the powder accumulation height detector 23, and in addition to adjusting the powder supply amount to the substrate 3, adjusts the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4. Thereby, in the powder coating apparatus 1, it becomes easier to control the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the substrate 3 and the squeegee 2 within a desired range. In particular, by setting Z to a range greater than 1 and less than or equal to 3, aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed. Therefore, continuous and precise coating with little variation in film thickness can be achieved.

[0061] For example, during continuous production, when the powder accumulation 24 increases, the powder accumulation height 20 increases, and Z approaches 3, first, the powder coating apparatus 1 decreases the powder supply amount. When it is desired to further obtain the effect of suppressing the increase in the powder accumulation height 20 in this situation, it is advisable to increase the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4. By adjusting in this way, in the powder coating apparatus 1, an effect of promoting the entry of the powder 4 into the gap between the substrate 3 and the squeegee 2 can be obtained, so that an effect of suppressing a further increase in the powder accumulation height 20 can be obtained.

[0062] Also, for example, at the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side of the relative movement direction 7 of the base material 3, the powder accumulation height 20 is detected by the powder accumulation height detector 23. Without adjusting the powder supply amount, the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4 may be adjusted. Also, after adjusting the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4, the powder supply amount may be further adjusted. Further, the adjustment of the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4 and the adjustment of the powder supply amount may be performed simultaneously. In any case, similarly, the effect of controlling the powder accumulation height 20 can be obtained. From this, in the powder coating apparatus 1, it becomes easier to control the ratio Z between the powder accumulation height 20 and the gap distance 21 between the base material 3 and the squeegee 2 within a desired range. In particular, by setting Z to a range greater than 1 and less than or equal to 3, aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed, enabling continuous and stable precision coating with little film thickness variation.

[0063] (Embodiment 6) FIG. 6 is a schematic view showing a powder coating apparatus 1 according to an embodiment of the present disclosure.

[0064] The powder coating apparatus 1 of the present disclosure is basically the same in configuration as that of Embodiment 4, except that it includes a third control unit 14 that adjusts the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4 based on the powder accumulation height 20 detected by the powder accumulation height detector 23 at the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2. Therefore, the basic configuration of the powder coating apparatus 1 in the present embodiment will be omitted from the appropriate description.

[0065] The powder coating apparatus 1 detects the powder accumulation height 20 at the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side of the relative movement direction 7 of the substrate 3 with respect to the squeegee 2 by the powder accumulation height detector 23, and in addition to adjusting the powder supply amount to the substrate 3, adjusts the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4. In the powder coating apparatus 1, it becomes easier to control the ratio Z between the powder accumulation height 20 and the gap distance 21 between the substrate 3 and the squeegee 2 within a desired range. In particular, by setting Z to a range greater than 1 and less than or equal to 3, aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed, so that continuous and precise coating with little variation in film thickness can be achieved stably.

[0066] For example, during continuous production, when the powder reservoir 24 becomes larger, the powder accumulation height 20 increases and Z approaches 3, first the powder coating apparatus 1 reduces the powder supply amount. In this situation, if it is desired to further obtain the effect of suppressing the increase in the powder accumulation height 20, it is advisable to increase the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4. By adjusting in this way, in the powder coating apparatus 1, an effect of promoting the entry of the powder 4 into the gap between the substrate 3 and the squeegee 2 can be obtained, so that an effect of suppressing a further increase in the powder accumulation height 20 can be obtained.

[0067] Further, for example, the powder accumulation height 20 is detected by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 that contacts the powder 4 on the upstream side of the relative movement direction 7 of the base material 3. Without adjusting the powder supply amount, the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4 may be adjusted. Further, after adjusting the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4, the powder supply amount may be further adjusted. Further, the adjustment of the inclination angle 6 of the surface 10 of the squeegee 2 that contacts the powder 4 and the adjustment of the powder supply amount may be performed simultaneously. In any case, similarly, the effect of controlling the powder accumulation height 20 can be obtained. From this, in the powder coating apparatus 1, it becomes easier to control the ratio Z between the powder accumulation height 20 and the gap distance 21 between the base material 3 and the squeegee 2 within a desired range. In particular, by setting Z to a range greater than 1 and less than or equal to 3, aggregation and retention of the powder 4 are less likely to occur, and powder clogging can be suppressed. Therefore, continuous and precise coating with a small film thickness variation can be achieved.

[0068] Hereinafter, embodiments of the present disclosure will be described in more detail using specific experimental examples. Note that the present disclosure is not limited by the following experimental examples, and can be appropriately modified and implemented without changing the gist thereof.

[0069] (Experimental Example) As an experimental example, using the powder coating apparatus 1 of Embodiments 1 to 6, a film of the positive electrode mixture layer 25 containing the positive electrode active material and the solid electrolyte of the all-solid-state battery was formed. As the positive electrode active material, LiNi1 / 3Co1 / 3Mn1 / 3 with an average particle diameter D50 of 5 μm was used. As the solid electrolyte, Li2S-P2S5 with an average particle diameter D50 of 0.8 μm was used, and a mixture mixed so as to have a volume ratio of 7:3 was formed into a film. Further, the mixture was supplied onto the base material 3 on the upstream side of the relative movement direction 7 of the base material 3 with respect to the squeegee 2, and the mixture was leveled by the powder coating apparatus 1 of Embodiments 1 to 6 of the present disclosure. Thus, film formation with a coating width of 50 mm, a coating length of 200 mm, and a target film thickness of 300 μm was performed 30 times each on the aluminum foil serving as the base material 3. The coating speed was set to 10 m / min. The gap distance 21 between the base material 3 and the squeegee 2 was set to 300 μm.

[0070] The powder inclination angle detector 11 captures an image of the shadow of the powder 4 supplied onto the base material 3 lifted by a light source with a camera, and captures the position of the surface of the powder layer formed by the powder 4 supplied onto the base material 3 by image processing such as binarization processing, and detects the angle 8 or angle 9 between the surface of the powder layer formed by the powder 4 supplied onto the base material 3 and the base material 3.

[0071] In the experimental example of Embodiment 1, while detecting the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled to be equal to or greater than the detected angle 8.

[0072] In the experimental example of Embodiment 2, while detecting the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled to be equal to or greater than the detected angle 9.

[0073] The powder accumulation height detector 23 captures an image of the shadow of the powder accumulation 24 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 lifted by a light source with a camera, captures the position of the surface of the powder accumulation 24 by image processing such as binarization processing, and detects the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3.

[0074] In the experimental example of Embodiment 3, while detecting the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled to be equal to or greater than the detected angle 8. Further, the powder accumulation height detector 23 detected the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the squeegee 2. The powder coating apparatus 1 controlled the powder supply amount to the base material 3 such that the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the base material 3 and the squeegee 2 was greater than 1 and equal to or less than 3.

[0075] In the experimental example of Embodiment 4, while detecting the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled to be equal to or greater than the detected angle 9.

[0076] Further, the powder accumulation height detector 23 detected the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the squeegee 2. The powder coating apparatus 1 controlled the powder supply amount to the base material 3 such that the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the base material 3 and the squeegee 2 was greater than 1 and equal to or less than 3.

[0077] In the experimental example of Embodiment 5, while detecting the angle 8 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled to be equal to or greater than the detected angle 8. Further, the powder accumulation height detector 23 detected the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the squeegee 2. The powder coating apparatus 1 controlled the powder supply amount to the base material 3 such that the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the base material 3 and the squeegee 2 was greater than 1 and equal to or less than 3. Further, while monitoring the transition of Z in that situation, when a sign that Z would go out of the range greater than 1 and equal to or less than 3 was observed, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled.

[0078] In the experimental example of Embodiment 6, while detecting the angle 9 between the surface of the powder layer formed by the powder 4 supplied from the powder supply unit 5 to the base material 3 and the base material 3 on the downstream side in the relative movement direction 7 of the base material 3 with respect to the powder supply position 22, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled to be equal to or greater than the detected angle 9. Further, the powder accumulation height detector 23 detected the powder accumulation height 20 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3 with respect to the squeegee 2. The powder coating apparatus 1 controlled the powder supply amount to the base material 3 such that the ratio Z between the powder accumulation height 20 and the distance 21 of the gap between the base material 3 and the squeegee 2 was greater than 1 and equal to or less than 3. Further, while monitoring the transition of Z in that situation, when a sign that Z would go out of the range greater than 1 and equal to or less than 3 was observed, the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4 was controlled.

[0079] Further, as comparative examples, when using the blade-shaped squeegee 100 which is the prior art shown in FIGS. 9 and 10 (Comparative Example 1), and when vibrating the columnar squeegee 150 which is the prior art shown in FIGS. 11 and 12 in the relative movement direction 7 of the base material 3 with respect to the squeegee 150 and the reverse direction thereof while maintaining the shortest distance 109 between the squeegee 150 and the base material 3 (Comparative Example 2), and when vibrating the columnar squeegee 150 which is the prior art shown in FIGS. 13 and 14 in a direction perpendicular to the relative movement direction 7 of the base material 3 with respect to the squeegee 150 while maintaining the shortest distance 109 between the squeegee 150 and the base material 3 (Comparative Example 3), film formation was similarly carried out. Here, the vibration conditions of the squeegee 150 are the conditions disclosed in Patent Document 2. The vibration frequency of the squeegee 150 was 700 Hz and the amplitude was 5 μm.

[0080] Regarding the coating continuity when forming a plurality of positive electrode active material layers 25, when powder clogging occurred at the squeegee 150 even once and normal film formation could not be achieved, it was designated as "C", and when no powder clogging occurred and all normal film formation was achieved, it was designated as "A".

[0081] Further, regarding the film thickness variation of the obtained positive electrode active material layer 25, the film thickness variation within the surface of the positive electrode active material layer 25 was measured using a laser displacement meter as shown in FIG. 8, across the powder layer at 5 mm intervals in the coating width direction and the coating direction respectively. Regarding the maximum value of the film thickness variation ((maximum value of film thickness - minimum value of film thickness) / (average value of film thickness)) in each powder layer, less than ±2.5% was designated as "A", ±2.5% or more and less than ±5% was designated as "B", and ±5% or more was designated as "C". In addition, during the coating of a predetermined number of sheets, when powder clogging occurred at the squeegee 150 even once and normal film formation could not be achieved, it was not measured and designated as "-", and the film thickness variation evaluation was performed only when no powder clogging occurred and all normal film formation was achieved.

[0082] The results of each embodiment according to the present disclosure (Experimental Examples 1 to 6) and the results of the comparative examples according to the prior art are shown in Table 1 of FIG. 15. In Table 1, the results at the time when a total of 10 positive electrode active material layers 25 were formed for each experimental example and comparative example respectively, and further, when an additional 20 films were formed respectively and a total of 30 films were formed for each, are shown.

[0083] From the results shown in Table 1, when comparing at the time when 10 film formations were carried out, in Experimental Examples 1 to 6 which are Embodiments 1 to 6 of the present disclosure, in any of the experimental examples, powder clogging did not occur and all could be film-formed normally. On the other hand, in Comparative Examples 1 to 3 according to the prior art, powder clogging occurred in any of the comparative examples, and a situation where normal film formation could not be achieved occurred.

[0084] Thus, in the prior art, when in a stationary state, aggregation progresses, the fluidity of the powder 4 is promoted to decrease. For example, for a very small powder 4 with a particle size of several tens of μm to sub-μm, the effect of suppressing powder clogging for realizing the coating continuity essential for mass production becomes insufficient.

[0085] On the other hand, in Experimental Examples 1 to 6 which are Embodiments 1 to 6 of the present disclosure, in order to form a powder layer with little film thickness variation, the fluidity of the powder 4 in the state supplied onto the base material 3 immediately before leveling with the squeegee 2 was grasped. Further, in Experimental Examples 1 to 6, based on the fluidity of the powder 4, controlling the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4), and detecting the powder accumulation height 20 with the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side of the relative movement direction 7 of the base material 3, and controlling the powder supply amount to the base material 3 and the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4). As a result, even for a very small powder 4 such as a powder 4 with a particle size of several tens of μm to sub-μm, in which aggregation progresses and the fluidity of the powder 4 is promoted to decrease when in a stationary state, it has become possible to sufficiently obtain the effect of suppressing powder clogging for realizing the coating continuity essential for mass production.

[0086] Also, from the results shown in Table 1, even when comparing at the time when 30 film formations were carried out, in Experimental Examples 1 to 6 which are Embodiments 1 to 6 of the present disclosure, powder clogging did not occur in any of the experimental examples, and all film formations could be carried out normally. From this also, in Experimental Examples 1 to 6 which are Embodiments 1 to 6 of the present disclosure, when in a stationary state, aggregation progresses, the fluidity of powder 4 is promoted to decrease, and for example, even for very small powder 4 such as having a particle diameter of several tens of μm to sub-μm, it was found that it is possible to sufficiently obtain the effect of suppressing powder clogging for realizing the coating continuity essential for mass production.

[0087] Also, regarding the film thickness variation of Experimental Examples 1 to 6 which are Embodiments 1 to 6 of the present disclosure, when comparing the time when 10 film formations were carried out and the time when 30 film formations were carried out, Experimental Examples 3 and 4 can form more films while suppressing film thickness variation than Experimental Examples 1 and 2, and furthermore, it was found that Experimental Examples 5 and 6 can form more films while suppressing film thickness variation than Experimental Examples 3 and 4. This is because in Experimental Examples 1 and 2, the fluidity of powder 4 in the state supplied onto the base material 3 immediately before leveling with the squeegee 2 is grasped, and based on that, the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4) are controlled. Also, compared with Experimental Examples 1 and 2, in Experimental Examples 3 and 4, the powder accumulation height 20 is detected by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3, and a function of controlling the powder supply amount to the base material 3 is added. Furthermore, compared with Experimental Examples 3 and 4, in Experimental Examples 5 and 6, the powder accumulation height 20 is detected by the powder accumulation height detector 23 on the surface 10 of the squeegee 2 in contact with the powder 4 on the upstream side in the relative movement direction 7 of the base material 3, and a function of controlling the setting conditions of the squeegee 2 (the inclination angle 6 of the surface 10 of the squeegee 2 in contact with the powder 4) is added. As in Experimental Examples 1 and 2, Experimental Examples 3 and 4, and Experimental Examples 5 and 6, as the function of grasping the fluidity of the powder 4 and the state of the powder accumulation 24 and controlling the coating conditions increases, it is considered that the effect that the response force to the change in the fluidity of the powder 4 and the state of the powder accumulation 24 increases during the continuation of the coating occurs.

[0088] Here, in the embodiments of the present disclosure, the powder 4 is exemplified as a group of particles containing an active material, but the same effect can be obtained with powders of other functional materials, and the raw materials, composition, particle shape, and particle diameter are not particularly limited. Further, the powder 4 may contain only one type of powder, or may contain two or more types of powders.

[0089] Further, the base material 3 is a long thin plate and is unwound from a wound state and wound up after coating, but it is not limited to such a form. The base material 3 having a desired shape may be relatively moved with respect to the squeegee 2 by a driving device (not shown), and after the coating of the powder 4 is completed, a new base material 3 may be intermittently relatively moved with respect to the squeegee 2 by a driving device (not shown). Further, the base material 3 does not have to be wound in a roll shape. The base material 3 is not limited to a sheet shape, and any shape that can be coated with the powder 4 using the powder coating apparatus 1 is acceptable. Further, in the present embodiment, the base material 3 is a current collector including a metal foil, but the material is not particularly limited, and any base material that can be coated with the powder 4 using the powder coating apparatus 1 can be used. <l

[0090] Note that, regarding the first control unit 12, the second control unit 13, and the third control unit 14, although they are separately described in the present embodiment for disclosing each control content, there is no problem even if they are an integrated control unit.

[0091] According to the present disclosure, a powder layer with little variation in film thickness can be formed on the surface of the base material.

Industrial Applicability

[0092] The powder coating apparatus of the present disclosure can produce a uniform powder layer with little variation in film thickness without using a solvent, and thus can also be applied to the formation of a paste layer or the like of a high-quality energy device (for example, an all-solid-state battery).

Explanation of Reference Numerals

[0093] 1 Powder coating apparatus 2 Squeegee 3 Base material 4 Powder 5 Powder supply section 6 Inclination angle of the surface of the squeegee in contact with the powder 7 Relative movement direction of the substrate with respect to the squeegee 8 Angle between the surface of the powder layer formed by the powder supplied from the powder supply section to the substrate and the substrate on the upstream side of the relative movement direction of the substrate with respect to the squeegee 9 Angle between the surface of the powder layer formed by the powder supplied from the powder supply section to the substrate and the substrate on the downstream side of the relative movement direction of the substrate with respect to the squeegee 10 Surface of the squeegee in contact with the powder 11 Powder inclination angle detector 12 First control unit 13 Second control unit 14 Third control unit 20 Powder storage height 21 Distance of the gap between the substrate and the squeegee 22 Powder supply position 23 Powder storage height detector 24 Powder storage 25 Positive electrode active material layer 100 Blade-shaped squeegee in the prior art 109 Shortest distance between the squeegee and the substrate 150 Columnar squeegee in the prior art

Claims

1. A powder supply unit for supplying powder onto the surface of a substrate, arranged so that a gap is formed between the substrate and the powder supply unit, adjusting the thickness of a powder layer composed of the powder supplied onto the surface of the substrate by the powder supply unit, and scanning in a state where the inclination angle of the surface in contact with the powder with respect to the normal direction of the surface of the substrate can be changed; a squeegee, a powder inclination angle detector for detecting the angle between the surface of the powder layer and the substrate, and a first control unit for adjusting the inclination angle of the surface of the squeegee in contact with the powder based on the inclination angle of the powder layer detected by the powder inclination angle detector. A powder coating apparatus.

2. The powder inclination angle detector is arranged on at least one of the upstream side or the downstream side in the relative movement direction of the substrate with respect to the squeegee with respect to the powder supply position to the substrate, and detects the angle between the surface of the powder layer formed by the powder supplied to the substrate and the substrate. The powder coating apparatus according to Claim 1.

3. A powder accumulation height detector for detecting the height of a powder accumulation on the surface of the squeegee in contact with the powder on the upstream side in the relative movement direction of the substrate with respect to the squeegee is provided. The powder coating apparatus according to Claim 1 or 2.

4. A second control unit for adjusting the powder supply amount to the substrate based on the powder accumulation height detected by the powder accumulation height detector is provided. The powder coating apparatus according to Claim 3.

5. A third control unit for adjusting the inclination angle of the surface of the squeegee in contact with the powder based on the powder accumulation height detected by the powder accumulation height detector is provided. The powder coating apparatus according to Claim 3 or 4.

6. The angle between the surface of the powder layer and the substrate is equivalent to the angle of repose of the powder in the state of being supplied onto the substrate. The powder coating apparatus according to any one of Claims 1 to 5.

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