Coating apparatus and coating method

Abstract

The purpose of this disclosure is to provide a coating apparatus and a coating method that can suppress the deterioration of the quality of coating liquid or coating slurry discharged by test spraying. [Solution] The coating apparatus of the present disclosure has a coating liquid recovery container 120 equipped with a nozzle 140 for discharging a coating liquid or coating slurry onto a conveyed substrate, and a coating liquid recovery port 130, and by inserting the nozzle 140 into the coating liquid recovery port 130, a sealed internal space can be formed inside the coating liquid recovery container 120.

Description

Technical Field

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

Background Art

[0002] As a coating method for applying a coating liquid to a substrate, there is a coating method using a nozzle. In such a coating method, in order to perform air bleeding (foam removal) in the supply path of the coating liquid and stably perform coating by the nozzle, as a preparation work before starting the operation of the apparatus, preliminary discharge of the coating liquid, so-called waste discharge, is performed. As methods for performing air bleeding by waste discharge, various methods have been proposed.

[0003] For example, Patent Document 1 and Patent Document 2 disclose a coating method in which a coating liquid is discharged from a die head and applied to the surface of a belt-like body that moves along a backup roll. At least as a preparation step before starting the application of the coating liquid by the die head, a discharge step of discharging the coating liquid from the die head onto a sub-roll that is rotationally driven is provided. According to the methods described in Patent Document 1 and Patent Document 2, it is said that the coating liquid can be discharged into the air without discharging the coating liquid onto the belt-like body and without allowing the coating liquid to flow down the lip surface of the die head.

[0004] Further, Patent Document 3 discloses a coating apparatus including a nozzle that discharges paint onto a traveling substrate and a supply means that supplies paint to the nozzle via a paint supply path. The nozzle is provided so as to be able to move closer to and away from the substrate by a swinging operation, and a driving means is provided that moves the nozzle closer to and away from the substrate in response to a stop / resumption operation of the paint supply by the supply means. According to the apparatus described in Patent Document 3, it is of course possible to prevent the paint from dripping at the end of the coating in the coating section, and it is said that the start and end of the coating can be made linear.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] International Publication No. 10 / 116442 [Patent Document 2] Japanese Patent Publication No. 2015-150542 [Patent Document 3] Japanese Patent Publication No. H11-244761 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The coating liquid or slurry discharged by the test run deteriorates in quality upon contact with the atmosphere, making it difficult to reuse as a coating liquid or slurry. Therefore, generally, the coating liquid or slurry discharged by the test run is discarded without being reused. In particular, when forming the active material layer using the above-mentioned coating method in battery manufacturing, the deterioration of the quality of the coating slurry, i.e., the electrode composite slurry, is a major problem, making it difficult to reuse the coating slurry discharged by the test run.

[0007] Therefore, the present disclosure aims to provide a coating apparatus and a coating method that can suppress the deterioration of the quality of coating liquid or coating slurry discharged by test spraying. [Means for solving the problem]

[0008] This disclosure aims to achieve the above objectives by the following means:

[0009] (Aspect 1) A nozzle for dispensing a coating liquid or coating slurry onto a substrate being transported, and Coating liquid recovery container equipped with a coating liquid recovery port. It has and By inserting the above nozzle into the coating liquid recovery port, a sealed internal space can be formed inside the coating liquid recovery container. Coating equipment. (Aspect 2) The apparatus according to embodiment 1, further comprising a suction pump, a filter, a storage container, an agitation unit attached to the storage container, and at least one of these downstream of the coating liquid recovery container. (Aspect 3) The apparatus according to embodiment 1 or 2, wherein the inner surface of the coating liquid recovery container is coated with a liquid-repellent coating agent. (Aspect 4) The apparatus according to any one of the embodiments 1 to 3, wherein the width of the coating liquid recovery port is 50 cm or more. (Appendix 5) A coating method using a coating apparatus described in any one of embodiments 1 to 4, The process involves dispensing the coating liquid or coating slurry from the nozzle onto the substrate being transported, and Before starting the application of the coating liquid or coating slurry using the above nozzle, the nozzle is inserted into the coating liquid recovery port to form the sealed internal space inside the coating liquid recovery container, and the coating liquid or coating slurry is discharged from the nozzle into the internal space. including, Coating method. [Effects of the Invention]

[0010] The apparatus and method of this disclosure can suppress the deterioration of the quality of the coating liquid or coating slurry discharged by test run. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a schematic diagram illustrating the coating apparatus in this disclosure. [Figure 2] Figure 2 is a schematic diagram illustrating the coating apparatus in this disclosure. [Modes for carrying out the invention]

[0012] Coating equipment The coating apparatus of this disclosure is A nozzle for dispensing a coating liquid or coating slurry onto a substrate being transported, and A coating liquid recovery container having a coating liquid recovery port and By inserting the nozzle into the coating liquid recovery port, an internal space sealed inside the coating liquid recovery container can be formed.

[0013] According to the above coating apparatus, deterioration in the quality of the coating liquid or coating slurry discharged by discard spraying can be suppressed.

[0014] In a conventional coating apparatus or method, the coating liquid or coating slurry discharged by discard spraying comes into contact with the atmosphere during recovery, thereby deteriorating the quality of the coating liquid or coating slurry.

[0015] In contrast, the coating apparatus of the present disclosure has a nozzle for discharging a coating liquid or coating slurry and a coating liquid recovery container having a coating liquid recovery port, and by inserting the nozzle into the coating liquid recovery port, an internal space sealed inside the coating liquid recovery container is formed. According to this, in the coating apparatus of the present disclosure, it is possible to suppress the coating liquid or coating slurry discharged by discard spraying from coming into contact with the atmosphere during recovery, thereby suppressing deterioration in the quality of the coating liquid or coating slurry.

[0016] Since deterioration in the quality of the electrode mixture slurry has a relatively large adverse effect on the performance of the resulting battery, the coating apparatus of the present disclosure can be particularly preferably used when forming an active material layer by coating an electrode mixture slurry on a substrate in battery manufacturing.

[0017] Hereinafter, embodiments of the present disclosure will be described in detail. Note that the present disclosure is not limited to the following embodiments and can be variously modified and implemented within the scope of the gist of the present disclosure. Also, in the description of the drawings, the same reference numerals are assigned to the same elements, and duplicate descriptions are omitted.

[0018] <Components of the coating apparatus> The coating apparatus of the present disclosure has a nozzle for discharging a coating liquid or coating slurry onto a conveyed substrate and a coating liquid recovery container having a coating liquid recovery port.

[0019] Figure 1 shows, but is not limited to, an embodiment of a coating apparatus in this disclosure. The coating apparatus 100 includes a coating liquid recovery container 120 and a nozzle 140. The coating liquid recovery container 120 has a coating liquid recovery port 130. Downstream of the coating liquid recovery container 120 is a storage container 170 with a suction pump 150, a filter 160, and a stirring section (not shown).

[0020] Figure 2 shows, but is not limited to, an embodiment of coating using the nozzle of the coating apparatus in this disclosure. The coating apparatus 100 is filled with a coating liquid 200, and the coating liquid 200 is applied to the transported substrate 300 from the tip of the nozzle 140.

[0021] (nozzle) In this disclosure, the coating apparatus has a nozzle which discharges a coating liquid or coating slurry and coats the coating liquid or coating slurry onto a conveyed substrate.

[0022] In this disclosure, the nozzle width can be any value according to the size of the substrate, etc. Specifically, the nozzle width may be 5 cm or more, 10 cm or more, 30 cm or more, 50 cm or more, 70 cm or more, or 90 cm or more, and may also be 200 cm or less, 170 cm or less, 150 cm or less, 130 cm or less, or 110 cm or less. In this disclosure, the nozzle width is the length of the nozzle in a direction perpendicular to the transport direction of the substrate to which the coating liquid or coating slurry is applied.

[0023] (Coating liquid recovery container) In this disclosure, the coating apparatus has a coating liquid recovery container, and the coating liquid recovery container has a coating liquid recovery port.

[0024] In this disclosure, the coating liquid recovery port can accommodate a nozzle, thereby forming an internal space within the coating liquid recovery container. At this time, there may be a gap between the coating liquid recovery port and the nozzle, and this gap may be reduced by placing a material such as rubber in the coating liquid recovery port and / or nozzle.

[0025] In this disclosure, the width of the coating liquid recovery port may be 5 cm or more, 10 cm or more, 30 cm or more, 50 cm or more, 70 cm or more, or 90 cm or more, and may also be 200 cm or less, 170 cm or less, 150 cm or less, 130 cm or less, or 110 cm or less. In this disclosure, the width of the coating liquid recovery port is the length of the coating liquid recovery port in the same direction as the width of the nozzle.

[0026] In this disclosure, the coating apparatus may further include, downstream of the coating liquid recovery container, a suction pump, a filter, a storage container, a stirring unit attached to the storage container, and at least one of these, a measuring unit.

[0027] (Suction pump) In this disclosure, the coating apparatus may be equipped with a suction pump downstream of the coating liquid recovery container. The suction pump can facilitate the flow of the coating liquid or coating slurry discharged from the nozzle downstream of the coating liquid recovery container.

[0028] (filter) In this disclosure, the coating apparatus may be equipped with a filter downstream of the coating liquid recovery container. The filter can remove impurities contained in the coating liquid or coating slurry discharged from the nozzle.

[0029] (Storage container) In this disclosure, the coating apparatus may include a storage container downstream of the coating liquid recovery container. The storage container can store the coating liquid or coating slurry discharged from the nozzle.

[0030] In this disclosure, the storage container may further have a stirring section. The stirring section can stir the coating liquid or coating slurry discharged from the nozzle.

[0031] (Measurement part) In this disclosure, the coating apparatus may include a measuring unit downstream of the coating liquid recovery container. The measuring unit can measure the solid content of the coating liquid or coating slurry discharged from the nozzle.

[0032] In this disclosure, the inner surface of the coating liquid recovery container may be coated with a liquid-repellent coating agent. In this case, the liquid-repellent coating agent may be, but is not limited to, Teflon®.

[0033] (Coating liquid or coating slurry) In this disclosure, the coating liquid or coating slurry is not particularly limited, but examples include electrode mixture slurry. Here, "electrode mixture slurry" means a mixture slurry containing at least active material particles and a dispersion medium.

[0034] In this disclosure, the solid content of the coating liquid or coating slurry is not particularly limited. "Coating liquid" refers to a liquid coating, and "coating slurry" refers to a suspension of liquid and insoluble particles.

[0035] <Functions of coating equipment> The coating apparatus of this disclosure can form a sealed internal space inside the coating liquid recovery container by inserting the nozzle into the coating liquid recovery port.

[0036] In this disclosure, "sealing" of the internal space means that by inserting the nozzle into the coating liquid recovery port of the coating liquid recovery container, the area of ​​the portion open to the outside of the coating liquid recovery container becomes 10 area % or less, 7 area % or less, or 5 area % or less of the area of ​​the coating liquid recovery port. The area of ​​this open portion may be greater than 0 area %, 1 area % or more, 3 area % or more, or 5 area % or more of the area of ​​the coating liquid recovery port. By having the area of ​​the open portion greater than 0 area %, it is possible to suppress a decrease in the air pressure of the internal space even when a suction pump is provided downstream of the coating liquid recovery container to promote the coating liquid or coating slurry from the coating liquid recovery container.

[0037] ≪Coating Method≫ The coating method disclosed herein is A coating method using the coating apparatus described herein, The process involves dispensing the coating liquid or coating slurry from the nozzle onto the substrate being transported, and Before starting the application of the coating liquid or coating slurry using the above nozzle, the nozzle is inserted into the coating liquid recovery port to form the sealed internal space inside the coating liquid recovery container, and the coating liquid or coating slurry is discharged from the nozzle into the internal space. Includes.

[0038] The present disclosure will be further described with reference to the following embodiments, but the scope of the present disclosure is not limited to these embodiments. [Examples]

[0039] ≪Method for measuring solid content≫ In this example, the solid content of the coating slurry was determined using the following method. First, the mass of the coating slurry was measured and recorded as the total mass. Then, the solvent in the coating slurry was evaporated by drying at 50°C for 0.5 hours, and the mass of the coating slurry was measured again to record the solid content mass. The solid content of the coating slurry was calculated using the following formula. Solid content percentage (%) = (Mass of solid content / Total mass) × 100

[0040] ≪Comparative Example 1≫ A coating solution with a solid content of 57.0% was prepared, and this coating slurry was filled into the supply container of the coating apparatus.

[0041] The tip of the nozzle was inserted into the coating liquid collection port of the coating liquid recovery container. At this time, the top of the coating liquid recovery container was open, and there was a gap between the tip of the nozzle and the coating liquid collection port. The area of ​​the portion of the coating liquid recovery container that was open to the outside (the area of ​​the open top of the coating liquid recovery container and the area of ​​the gap between the tip of the nozzle and the coating liquid collection port) totaled approximately 1500 area % of the area of ​​the coating liquid collection port.

[0042] Furthermore, as shown in Figure 1, the coating liquid recovery container had a suction pump, a filter, and a storage container with an agitator downstream of it, in that order. The width of the nozzle and the coating liquid recovery port was 126 cm.

[0043] The coating slurry was discharged from the nozzle into the internal space of the coating liquid recovery container. Then, using a suction pump, the coating slurry discharged into the coating liquid recovery container was passed through a filter and sent to a storage container, where it was stirred in an agitator attached to the storage container to obtain the post-test coating slurry for Comparative Example 1.

[0044] ≪Comparative Example 2≫ A post-treatment coating slurry was obtained in Comparative Example 2 in the same manner as in Comparative Example 1, except that the top of the coating liquid recovery container was not open. At this time, the area of ​​the portion of the coating liquid recovery container that was open to the outside (the area of ​​the gap between the nozzle tip and the coating liquid recovery port) was approximately 30% of the area of ​​the coating liquid recovery port.

[0045] Example 1 Except for installing a rubber component between the coating liquid recovery port of the coating liquid recovery container and the tip of the nozzle to reduce the gap, the post-test coating slurry of Example 1 was obtained in the same manner as in Comparative Example 2. At this time, the area of ​​the portion of the coating liquid recovery container that is open to the outside (the area of ​​the gap between the tip of the nozzle and the coating liquid recovery port) was approximately 1 area % of the area of ​​the coating liquid recovery port.

[0046] ≪Rating≫ The solid content of the coating slurry after sacrificial application was measured in Comparative Examples 1 and 2 and Example 1. The results are shown in Table 1 below. The solid content of the coating slurry after sacrificial application in Comparative Examples 1 and 2 was higher than the solid content of the coating slurry used. Therefore, the components of the coating slurry changed due to being discharged as a sacrificial application. In contrast, the solid content of the coating slurry after sacrificial application in Example 1 was the same as the solid content of the coating slurry, indicating that the components of the coating slurry did not change due to being discharged as a sacrificial application. From the above, it has been shown that the deterioration of the quality of the coating slurry due to sacrificial application can be reduced by using the apparatus of this disclosure.

[0047] [Table 1] [Explanation of symbols]

[0048] 100 Coating equipment 120 Coating liquid recovery container 130 Coating liquid recovery port 140 nozzles 150 Suction Pump 160 filters 170 Storage containers 200 coating liquid 300 Base material

Claims

1. A nozzle for dispensing a coating liquid or coating slurry onto a substrate being transported, and Coating liquid recovery container equipped with a coating liquid recovery port. It has and By inserting the nozzle into the coating liquid recovery port, a sealed internal space can be formed inside the coating liquid recovery container. Coating equipment.

2. The apparatus according to claim 1, further comprising a suction pump, a filter, a storage container, a stirring unit attached to the storage container, and at least one of these downstream of the coating liquid recovery container.

3. The apparatus according to claim 1, wherein the inner surface of the coating liquid recovery container is coated with a liquid-repellent coating agent.

4. The apparatus according to claim 1, wherein the width of the coating liquid recovery port is 50 cm or more.

5. A coating method using a coating apparatus according to any one of claims 1 to 4, The process involves discharging the coating liquid or coating slurry from the nozzle onto the substrate being transported, and Before the start of coating the coating liquid or coating slurry with the nozzle, the nozzle is inserted into the coating liquid recovery port to form the sealed internal space inside the coating liquid recovery container, and the coating liquid or coating slurry is discharged from the nozzle into the internal space. including, Coating method.

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