CN111760749B

CN111760749B - Coating head assembly and coating machine

Info

Publication number: CN111760749B
Application number: CN202010645867.8A
Authority: CN
Inventors: 甘旻谕; 赖俞丞; 涂晋益; 廖经皓
Original assignee: Interface Optoelectronics Shenzhen Co Ltd; Interface Technology Chengdu Co Ltd; General Interface Solution Ltd
Current assignee: Interface Optoelectronics Shenzhen Co Ltd; Interface Technology Chengdu Co Ltd; General Interface Solution Ltd
Priority date: 2020-07-07
Filing date: 2020-07-07
Publication date: 2022-01-04
Anticipated expiration: 2040-07-07
Also published as: CN111760749A; TWI765300B; TW202202233A

Abstract

The invention relates to a coating head component and a coating machine, which comprises a body, a liquid injection port and a liquid outlet, wherein a flow balance area is arranged in the body, the liquid outlet is arranged at one side of the body opposite to the liquid injection port, and when fluid flows into the body from the liquid injection port, the flow balance area adjusts the flow characteristic of the fluid, so that the fluid flowing out of the body from the liquid injection port is uniformly coated on a target piece.

Description

Coating head assembly and coating machine

Technical Field

The present invention relates to a coating head assembly and a coating machine, and more particularly, to a coating head assembly capable of uniformly coating a target with a fluid and a coating machine using the same.

Background

Slit Die Coating (slit Die Coating) is a precision Coating process technology, and is applied to the Coating of continuous Roll-to-Roll (R2R) substrates such as carrier boards (e.g., flexible printed circuit boards, adhesive-backed copper foils …, etc.), optical films (e.g., polarizing films, diffusion films …, etc.), battery plates (e.g., solar cells), etc. of electronic components, and also to the Coating of single-Sheet (Sheet to Sheet, S2S) non-continuous substrates (e.g., conductive films of organic light emitting diodes, optical films of liquid crystal panels, etc.), or the Coating of biomedical industries (e.g., biochip films).

The operation principle of the slit coating technology is that a fluid (paint) is injected into a coating head assembly by a quantitative pump in a slit coater, and the fluid is coated on a target component from an outlet of the coating head assembly. The quantitative pump provides the uniformity of the moving direction of the target, and the coating head assembly provides the uniformity of the width direction of the target, so as to meet the requirement of completely and uniformly coating the fluid on the target. It is known that the average thickness of the coating film is determined by the pump flow rate, the coating width and the coating speed, i.e. the coating head assembly is important for the slit coating technique, and is one of the important factors for determining the coating quality.

However, in the structure of the conventional head assembly, referring to fig. 1, the head assembly 1 has only one fluid injection port 10, and the outlet channel 12 of the head assembly 1 outputting the fluid is a narrow slit, so that, referring to fig. 2, for the head assembly 1 with a channel having a width of about 520mm, the flow rate of the fluid in the channel 12 is faster as it approaches the position of the injection port 10 (for example, the channel width is 260mm in fig. 2), and the flow rate of the fluid is gradually slower at positions gradually away from the channel inlet up to both ends of the channel (for example, at positions of 30 to 240mm in the channel width and 280 to 490mm in the dashed circle in fig. 2), that is, the flow rate of the fluid in the channel 12 is not uniform, resulting in uneven thickness of the fluid coated on the target. Therefore, how to improve the structure of the coating head and effectively solve the problem of non-uniform flow rate of the colloid so as to achieve the requirement of coating thickness uniformity is an urgent problem to be solved at present.

Disclosure of Invention

In view of the problems of the prior art, it is an object of the present invention to provide a coating head assembly capable of uniformly coating a fluid on a target object such that the coating thickness on the target object is uniform, or at least the difference in the coating thickness is within an allowable error value.

According to the above object, there is provided a coating head assembly, comprising a body, a liquid inlet and a liquid outlet, wherein the liquid inlet is disposed at one side of the body for injecting a fluid into the body, the liquid outlet is disposed at one side of the body opposite to the liquid inlet, and a flow channel is disposed in the body and extends from the body to the outside of the body and communicates with the liquid outlet for outputting the fluid out of the body and coating the fluid on a target member, a partition plate is further disposed in the body, a plurality of flow balance regions are disposed on the partition plate, each flow balance region communicates with the flow channel, and each flow balance region adjusts a flow characteristic of the fluid, so that the fluid uniformly flows out of the liquid outlet from the flow channel, and the fluid is uniformly coated on the target member.

The body further comprises a spacing piece, a first coating head and a second coating head, the spacing piece comprises a first surface, a second surface and a bottom surface, the first surface is opposite to the second surface, the bottom surface is respectively connected with the first surface and the second surface, a notch is arranged on the bottom surface and serves as a liquid outlet, the notch penetrates from the first surface to the second surface, the first coating head is connected to the first surface, a partition plate is arranged in the first coating head, a liquid injection port is formed in one side, away from the first surface, of the first coating head, the second coating head is connected to the second surface, a liquid outlet is formed in one side, away from the second surface, of the second coating head, and the first coating head, the second coating head and the spacing piece are matched with each other to form a flow channel at the notch.

The first coating head is provided with a cavity, the cavity is divided into a first compartment and a second compartment by a partition board, the partition board is provided with a plurality of hole pieces, each hole piece comprises a first hole and a plurality of second holes, the first hole is arranged at the central position of the hole piece, each second hole is distributed on the hole piece around the first hole, each first hole and each second hole correspond to the first compartment and are respectively liquid inlet channels, each first hole and each second hole correspond to the second compartment and are respectively liquid conveying channels, each liquid inlet channel corresponds to one of the liquid conveying channels, and each flow balance area is formed by each liquid inlet channel and the corresponding liquid conveying channel.

Wherein the aperture of the first hole is larger than that of the second hole.

Wherein the difference in flow velocity of the fluid from the center to the two sides of the flow channel is less than 0.36%.

Wherein the height of the partition plate is H, the maximum height of each hole is H, wherein 1/2H is ≦ H < H.

Wherein the length of the partition board is L, and the number of the hole pieces is 1/5L-1/10L.

The flow detection unit comprises a controller, a first sensing element and a second sensing element, wherein the first sensing element and the second sensing element are respectively used for sensing the flow characteristics of fluid flowing through each liquid inlet channel and each liquid conveying channel and respectively generating a first sensing signal and a second sensing signal according to the flow characteristics, the controller is electrically connected with the first sensing element and the second sensing element and receives the first sensing signal and the second sensing signal, and the controller adjusts the flow characteristics of the fluid injected into the body from the liquid injection port according to the first sensing signal and the second sensing signal, so that the fluid can flow through each liquid inlet channel and the corresponding liquid conveying channel and can be uniformly converged at the liquid outlet.

The fluid system is a piezoelectric material, the target component is a substrate, and the coating head component coats the fluid on the substrate to form the flexible piezoelectric film.

According to the above object, a coating machine is provided, which comprises a coating platform and a coating head assembly as described above, wherein the coating platform is provided for placing a target object, and the coating head assembly is provided at a position corresponding to the coating platform and is used for coating a fluid on the surface of the target object.

In summary, the coating head assembly of the present invention can uniformly coat the fluid on the target object, and further can detect the flow characteristics of the fluid by the flow rate detecting unit to adjust the flow characteristics of the fluid, so that the fluid can be uniformly coated on the target object as required.

Drawings

FIG. 1 is a schematic diagram of a conventional applicator head assembly for applying a fluid to a target.

FIG. 2 is a graph of experimental data for flow channels and fluid flow rates for a conventional coating head assembly.

FIG. 3 is a schematic diagram of a coater of the present invention applying fluid to a target using a coating head assembly.

FIG. 4 is an exploded perspective view of the applicator head assembly of the present invention.

FIG. 5 is a cross-sectional schematic view of a coating head assembly of the present invention.

FIG. 6 is a schematic view of the orifice of the present invention.

FIG. 7 is a schematic cross-sectional view of a first coating head according to the present invention.

FIG. 8 is a front perspective view of a separator in the first coating head of the present invention.

FIG. 9 is a schematic perspective side view of a separator in the first coating head of the present invention.

FIG. 10 is a schematic view of the fluid exit port of the applicator head assembly of the present invention.

FIG. 11 is a graph of experimental data for flow channels and fluid flow rates for a coating head assembly of the present invention.

Reference numerals:

1: coating head assembly

10: fluid injection port

12. 20: flow passage

2: body

22: partition board

220: flow balance area

2200: infusion channel

2206: liquid inlet channel

222: hole piece

2220: a first hole

2222: second hole

24: spacing piece

240: first surface

242: second surface

244: bottom surface

2440: gap

26: first coating head

260: chamber

2600: the first compartment

2602: second compartment

28: second coating head

3: liquid filling port

4: liquid outlet

5: target part

6: flow rate detection unit

60: first sensing element

62: second sensing element

7: coating platform

H: height of the partition plate

h: height of flow balance area

L: length of the partition plate

Detailed Description

For the purpose of understanding the nature, content and advantages of the invention, as well as the objects and advantages achieved thereby, reference should be made to the following detailed description of illustrative embodiments of the invention, which is to be read in connection with the accompanying drawings, wherein the same is illustrated in the accompanying drawings and described below, wherein the same is not to be considered as limiting the scope of the invention, which is defined by the appended claims.

Referring to fig. 3, the present invention relates to a coating head assembly, which comprises a main body 2, a liquid injection port 3 and a liquid outlet 4, referring to fig. 4, wherein a flow channel 20 is disposed in the main body 2, and the flow channel 20 extends from the inside of the main body 2 to the outside of the main body 2. The body 2 is further provided with a partition plate 22, the partition plate 22 is provided with a plurality of flow balance areas 220, and each flow balance area 220 is communicated with the flow passage 20 in the body 2. The liquid injection port 3 is disposed on one side of the main body 2, and the liquid injection port 3 is communicated with the flow channel 20, the fluid is injected into the main body 2 from the liquid injection port 3 and flows into the flow channel 20 through the flow balance regions 220, the liquid outlet 4 is disposed on one side of the main body 2 opposite to the liquid injection port 3, the liquid outlet 4 is communicated with the flow channel 20 for outputting the fluid in the flow channel 20 out of the main body 2 and coating on the target member 5, and the flow balance regions 220 adjust the flow characteristics of the fluid, so that the fluid uniformly flows out of the liquid outlet 4 from the flow channel 20, and the fluid is uniformly coated on the target member 5, for example: the applicator head assembly applies fluid onto a surface of a target 5 (e.g., a substrate) such that the target 5 forms a flexible piezoelectric film.

In an embodiment of the present invention, referring to fig. 4 and 5, the body 2 further includes a spacer 24, a first coating head 26, and a second coating head 28, the spacer 24 includes a first surface 240, a second surface 242, and a bottom surface 244, the bottom surface 244 is respectively connected to the first surface 240 and the second surface 242, and the first surface 240 is opposite to the second surface 242. The bottom surface 244 is provided with a notch 2240 as the liquid outlet 4, the notch 2240 penetrates from the first surface 240 to the second surface 242, the first coating head 26 is connected to the first surface 240, the separation plate 22 is arranged in the first coating head 26, the second coating head 28 is connected to the second surface 242, and the partition piece 24, the first coating head 26 and the second coating head 24 are matched with each other to form the flow passage 20 at the notch 2240.

Referring to fig. 5, the first coating head 26 has a chamber 260 therein, and the chamber 260 is divided into a first compartment 2600 and a second compartment 2602 by a partition plate 22, wherein the first compartment 2600 is located at a position where the chamber 260 is far away from the flow channel 20, and the second compartment 2602 is located at a position where the chamber 260 communicates with the flow channel 20.

Referring to fig. 6, the partition plate 22 is provided with a plurality of hole members 222, each hole member 222 includes a first hole 2220 and a plurality of second holes 2222, the first hole 2220 is disposed at a central position of the hole member 222, and each second hole 2222 is distributed on the hole member 222 around the first hole 2220.

Referring to fig. 7, the first compartment 2600 corresponds to each first hole 2220 and each second hole 2222 respectively and is provided with a liquid inlet channel 2206, the second compartment 2602 corresponds to each first hole 2220 and each second hole 2222 respectively and is provided with a liquid inlet channel 2200, and one of the liquid inlet channels 2206 corresponds to one of the liquid inlet channels 2200 respectively. Each flow balance area 220 is formed by each liquid inlet channel 2206 and the corresponding liquid feeding channel 2200 provided on each orifice 222.

As described above, when the fluid flows from the first compartment 2600 to the second compartment 2602, the first holes 2220 and the second holes 2222 adjust the flow characteristics of the fluid, so that the fluid can uniformly flow into the flow channel 20. It should be particularly noted that the flow balance area 220 is not formed by the orifice 222, but any structure, shape or combination of structures and shapes that can uniformly coat the target object 5 after the fluid flows into the flow channel from the first coating head 26 are included in the flow balance area 220.

In this embodiment, please refer to fig. 7, which further includes a flow rate detecting unit 6, wherein the flow rate detecting unit 6 includes a controller (not shown), a first sensing element 60 and a second sensing element 62, the first sensing element 60 and the second sensing element 62 are respectively configured to sense a flow characteristic of a fluid flowing through each of the liquid inlet channels 2206 and each of the liquid inlet channels 2200, and respectively generate a first sensing signal and a second sensing signal according to the flow characteristic, the controller is electrically connected to the first sensing element 60 and the second sensing element 62, and receives the first sensing signal and the second sensing signal, and the controller further adjusts the flow characteristic of the fluid injected from the liquid inlet 3 into the body 2 according to the first sensing signal and the second sensing signal, so that the fluid flowing through each of the liquid inlet channels 2206 and the corresponding liquid inlet channels 2200 can be more evenly converged at the liquid outlet.

Referring to fig. 6 and 7, when the fluid passes through the first and

second holes

2220 and 2222 of the hole pieces 222 on the partition plate 22, the first and

second sensing elements

60 and 62 obtain stable sensing signals (e.g., pressure difference signals), and the controller calculates fluid characteristics such as: fluid flow rate and flow. For example, the controller calculates according to the bernoulli equation as follows:

wherein Q is_VThe volume flow is m 3/s; beta is the equivalent aperture ratio; a. the₀M2, which is the sum of the flow areas of the small first holes 2220 and the small second holes 2222; epsilon is a compressibility coefficient; Δ P is a differential pressure Pa across the partition plate 22; p is measured fluid density kg/m 3; c is the discharge coefficient) so that the volumetric flow rate and pressure of the fluid can be obtained through the first and

second holes

2220 and 2222 of each orifice 222 of the partition plate 22 according to the bernoulli equation. The controller can control the flow rate, flow rate or pressure of the fluid flowing into the first coating head 26, so that the fluid can balance and rectify the partition plate 22 to achieve a balance flow field and a stable flow rate, and further, the fluid can be uniformly coated on the target part 5.

In this embodiment, the height of the divider plate 22 is H (as shown in FIG. 8) and the maximum height of each orifice 222 is H (as shown in FIG. 9), where 1/2H ≦ H < H. The partition plate 22 has a length L (as shown in FIG. 9), and the number of the holes 222 is 1/5L-1/10L. Also, the fluid may be a polyvinylidene fluoride (PVDF) solution or a polyvinylidene fluoride (P (VDF-TrFE)) solution. The first sensing element 60 and the second sensing element 62 can be flow sensors, pressure sensors or flow rate sensors, and the Controller can be a Programmable Logic Controller (PLC). Wherein the flow characteristic refers to one or a combination of any two or more of the flow rate, flow velocity or pressure of the fluid.

Referring to fig. 1, the present invention further provides a coating machine, including a coating platform 7 and a coating head assembly as described above, wherein the coating platform 7 is provided for placing the target object 5, the coating head assembly is disposed at a position corresponding to the coating platform, and the coating head assembly and the coating platform 7 can move relatively and coat fluid on the surface of the target object.

Referring to fig. 10 and 11, according to the statistics of simulation experiments, when the fluid flows through the first hole 2220 and the second hole 2222 of each orifice 222, that is, enters the liquid inlet channel 2206 from each liquid inlet channel 2200, the fluid is balanced and rectified, so that the vortex is relatively reduced, the flow velocity of the fluid at the liquid outlet 4 is averaged, the flow velocity difference between the center and the two ends of the flow channel 20 is reduced, and from the viewpoint of fig. 11, the flow velocity difference between the center (at the position where the flow channel width is 260mm in fig. 11) and the two ends (at the positions where the flow channel width is about 25mm and 475mm in fig. 11) of the flow channel 20 is reduced to less than 0.36%, thereby effectively improving the problem of uneven coating thickness.

While the invention has been described with reference to specific preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims

1. A coating head assembly, comprising:

a body, comprising:

a flow passage arranged in the body and extending from the inside of the body to the outside of the body;

a partition plate arranged in the body, wherein the partition plate is provided with a plurality of flow balance areas which are communicated with the flow channel in the body, and fluid flows into the flow channel by adjusting the flow characteristics of the flow balance areas;

a liquid injection port arranged at one side of the body for injecting fluid into the body; and

a liquid outlet, which is arranged at one side of the body opposite to the liquid injection port and communicated with the flow passage, and is used for outputting the fluid passing through the flow balance areas out of the body and coating the fluid on a target piece;

wherein the body further comprises:

the spacer is provided with a first surface, a second surface and a bottom surface, wherein the first surface and the second surface are opposite to each other, the bottom surface is respectively connected with the first surface and the second surface, the bottom surface is provided with a notch to form the liquid outlet, and the notch penetrates from the first surface to the second surface;

the first coating head is connected to the first surface, and the partition plate is arranged in the first coating head; and

the second coating head is connected to the second surface;

wherein the spacing piece, the first coating head and the second coating head are mutually matched to form the flow channel at the notch;

wherein the first coating head is provided with a chamber, the chamber is divided into a first compartment and a second compartment by the partition board, the first compartment is located at a position where the chamber is far away from the flow channel, the second compartment is located at a position where the chamber is communicated with the flow channel, the partition board is provided with a plurality of hole pieces, and each hole piece respectively comprises:

a first hole provided at the center of the hole;

a plurality of second holes, each of which is distributed on the hole member around the first hole, and the aperture of each of the first holes is larger than that of each of the second holes;

the first compartment is a liquid inlet channel corresponding to the first holes and the second holes, the second compartment is a liquid delivery channel corresponding to the first holes and the second holes, one of the liquid inlet channels corresponds to one of the liquid delivery channels, and flow balance areas are formed;

the flow detection device further comprises a flow detection unit, wherein the flow detection unit comprises a controller, a first sensing element and a second sensing element, the first sensing element and the second sensing element are respectively used for sensing the flow characteristics of the fluid flowing through the liquid inlet channels and the liquid conveying channels and respectively generating a first sensing signal and a second sensing signal according to the flow characteristics, the controller is electrically connected with the first sensing element and the second sensing element and receives the first sensing signal and the second sensing signal, the controller adjusts the flow characteristics of the fluid injected into the body from the liquid inlet according to the first sensing signal and the second sensing signal, and the fluid flows through the liquid inlet channels and the liquid conveying channels and is evenly converged at the liquid outlet.

2. The applicator head assembly of claim 1, wherein the difference in flow velocity across the flow channel from center to side is less than 0.36%.

3. The applicator head assembly of claim 1, wherein the height of the divider plate is H and the maximum height of each orifice member is H, wherein 1/2H ≦ H < H.

4. The applicator head assembly of claim 1, wherein the divider plate has a length L and the number of orifices is 1/5L-1/10L.

5. The coating head assembly of any of claims 1-4 wherein the fluid being coated comprises piezoelectric material and the target is a substrate, the fluid being coated on the substrate through the coating head assembly to form a flexible piezoelectric film.

6. A coater, comprising:

a coating platform for placing the target object; and

the coating head assembly of claim 5, disposed at a position corresponding to the coating platform, and coating the fluid on the surface of the target member.