A film-forming liquid injection device for centrifugal film making

Abstract

The present invention relates to the field of thin film material and device manufacturing, and specifically to a film-forming liquid injection device for centrifugal film-making equipment. The device comprises: a rotating drum, a film-forming substrate, a needle, a device for moving the needle along the rotating axis of the drum, a device for adjusting the needle injection angle, a needle telescopic device, and a film-forming liquid boosting assembly. The film-forming substrate is arranged on the inner surface of the rotating drum, a slide bar 1 is installed on the device for moving the needle along the rotating axis of the drum, and the slide bar 1 is in sliding cooperation with the device for moving the needle along the rotating axis of the drum. One end of the needle injection angle adjustment device is installed at the tail end of the slide bar 1, and the other end of the needle injection angle adjustment device is installed with a needle telescopic device. The needle is installed on the needle telescopic device, and the needle is connected to the film-forming liquid boosting assembly through a pipeline. The device of the present invention is mainly used to inject film-forming liquids of different substances into the surface of the rotating substrate in the form of a liquid column to achieve precise control and preparation of the film structure.

Description

Technical Field

[0001] The present invention relates to the field of thin film material and device manufacturing, and in particular to a film forming liquid injection device for centrifugal film making equipment, which is mainly used to inject film forming liquids of different substances into the surface of a rotating substrate in the form of liquid columns to achieve precise control and preparation of thin film structures. Background Art

[0002] Flexible large-area uniform nano-thin film materials can be widely used in technical fields such as optoelectronic devices, energy storage devices, protective functional coatings, catalytic synthesis, composite materials, etc., and the efficient control preparation of nano-thickness thin film materials with uniform thickness is the key process basis for realizing the above applications. At present, the commonly used nano-thickness thin film material preparation technologies in industry mainly include evaporation, magnetron sputtering, spraying, spin coating, scraping, inkjet printing, etc. Among them, evaporation and magnetron sputtering can achieve uniform thickness of material deposition, but their operation is complicated, the equipment cost is high, and the requirements for target materials are extremely high. Spin coating and inkjet printing have a small action area and low efficiency, so it is impossible to prepare thin film materials on a large area, and the uniformity of large areas is poor; spraying and scraping processes can achieve the preparation of large-area thin film materials, but it is usually difficult to prepare nano-thickness thin film materials.

[0003] A Chinese invention patent application (publication number CN108568926A) proposes a method for efficiently preparing highly oriented and dense two-dimensional material films. The method uses a round tube with a smooth inner surface as a casting mold. When the mold rotates at high speed in a circular direction, a solution containing two-dimensional materials is poured into the mold, and the two-dimensional materials are assembled into a film using centrifugal force. This method is the centrifugal film-making technology, which can be used to obtain highly oriented and dense ordered microstructured film materials. A Chinese invention patent application (publication number CN109177010A) proposes the basic structure of a device for thin film preparation based on this technology; at the same time, the device uses an atomization spraying process to deposit the film-forming liquid onto the surface of a rotating substrate film, and can prepare a continuous film material with a nanometer thickness, but there are problems such as poor uniformity, stringent requirements for the film-forming liquid, and the risk of explosion. In order to solve these problems, the Chinese invention patent application with application number: 201910460855.5 provides a new method for preparing thin films based on micro-printing nozzles or needles injecting film-forming liquid, which can achieve efficient controlled preparation of nano-thickness thin film materials with uniform thickness. Summary of the invention

[0004] The purpose of the present invention is to provide a basic structure and use method of a film-forming liquid injection device for centrifugal film-forming technology, to control the film-forming liquid injection method during the centrifugal film-forming process, thereby achieving control of the thickness of the nano-thin film structure on the surface of the substrate film and the film-forming area.

[0005] The technical solution of the present invention is:

[0006] A film-forming liquid injection device for centrifugal film forming, the device comprises: a rotating drum, a film-forming substrate, a needle, a device for moving the needle along the rotating axis of the drum, a needle injection angle adjustment device, a needle telescopic device, and a film-forming liquid pressurizing component, and the specific structure is as follows:

[0007] A film-forming matrix is ​​arranged on the inner surface of the rotating drum, a slide bar 1 is installed on the device for moving the needle along the rotating axis of the drum, the slide bar 1 is in sliding cooperation with the device for moving the needle along the rotating axis of the drum, one end of a needle injection angle adjustment device is installed at the tail end of the slide bar 1, and a needle telescopic device is installed at the other end of the needle injection angle adjustment device, and the needle injection angle adjustment device drives the needle telescopic device to rotate 360 ​​degrees; a needle is installed on the needle telescopic device, and the needle is connected to a film-forming liquid boosting assembly through a pipeline, and the pipeline passes through the needle telescopic device and the slide bar 1 in sequence.

[0008] The membrane-forming liquid injection device for centrifugal membrane formation has a needle shape that is linear or curved, and its length ranges from 0.1mm to 1000mm; the cross-sectional shape of the needle hole is circular, elliptical, square, rectangular, polygonal, or various regular or irregular shapes transformed from the above shapes; the aperture of the needle hole or the longest dimension of the internal connecting line of the hole cross section ranges from 1μm to 10cm; the needle material includes but is not limited to metal, inorganic non-metallic material or organic polymer material.

[0009] The membrane-forming liquid injection device for centrifugal membrane formation is preferably such that the length of the needle tip ranges from 5 mm to 100 mm; the aperture of the needle hole or the longest dimension of the internal connecting line of the hole cross section ranges from 10 μm to 2 mm; the metal is made of stainless steel, nickel, copper, gold or silver; the inorganic non-metallic material is made of glass, quartz, ceramic or graphite; the organic polymer material is made of polytetrafluoroethylene, polypropylene, polycarbonate, ABS plastic, polyvinyl chloride or polyethylene terephthalate.

[0010] The film-forming liquid injection device used for centrifugal film formation, the needle injection angle adjustment device includes but is not limited to a stepper motor, a DC motor or a servo motor; without adjusting the rotation speed of the substrate, the needle injection angle adjustment device is used to make the needle point in the opposite direction of the substrate rotation or in the forward direction of the substrate rotation.

[0011] The film-forming liquid injection device used for centrifugal film formation, the needle telescopic device includes but is not limited to a manual telescopic rod, an electric slide module or a pneumatic telescopic rod, the needle axial movement device along the rotation of the drum includes but is not limited to a manual slide, an electric slide or a pneumatic slide, and the film-forming liquid boosting component adopts a syringe, an injection pump, a peristaltic pump, a diaphragm pump or a liquid pump.

[0012] The membrane-forming liquid injection device for centrifugal membrane formation also includes residual liquid collection components before and after the membrane-forming liquid is injected, including but not limited to a fixed residual liquid collection tank, a movable residual liquid collection tank, residual liquid absorption cotton or a residual liquid recovery pipe.

[0013] The film-forming liquid injection device for centrifugal film formation is characterized in that the fixed residual liquid collecting tank is two semicircular collecting tanks arranged in parallel, and the two ends of the fixed residual liquid collecting tank are fixed in the rotating drum by two right-angled fixed residual liquid collecting tank brackets. The center of the fixed residual liquid collecting tank is concentric with the rotating drum, and the gap between the fixed residual liquid collecting tank and the film-forming substrate is 1 to 5 mm.

[0014] The film-forming liquid injection device used for centrifugal film formation is characterized in that the movable residual liquid collecting tank is a semicircular collecting tank, and the gap between the movable residual liquid collecting tank and the film-forming substrate is 1 to 5 mm; a second slide bar is installed on the collecting tank moving device, and the second slide bar is in sliding cooperation with the collecting tank moving device, and the movable residual liquid collecting tank is installed at the tail end of the second slide bar, and the movable residual liquid collecting tank extends into the rotating drum under the drive of the second slide bar.

[0015] In the membrane-forming liquid injection device for centrifugal membrane making, the residual liquid absorption cotton is in a hollow cylindrical shape, and the residual liquid absorption cotton is sleeved on the needle head, and one end of the residual liquid absorption cotton is flush with the needle tip of the needle head.

[0016] The membrane-forming liquid injection device used for centrifugal membrane formation is characterized in that the residual liquid recovery tube is in the shape of a tube with a combination of small holes and large holes in a stepped hole. The residual liquid recovery tube is sleeved on the needle through the small hole at one end, and the other end of the residual liquid recovery tube is a large hole. The needle tip of the needle is retracted 0.3 to 1 mm toward the other end face of the residual liquid recovery tube. The large hole forms a cavity of the residual liquid recovery tube, and the upper outer part of the cavity is connected to the absorption pump through a pipeline.

[0017] The design idea of ​​the present invention is:

[0018] The present invention is a basic structure of a film-forming liquid needle injection system for centrifugal film-making, which includes four basic components: a needle component, a needle injection angle and position adjustment component, a film-forming liquid pressurization component, and a residual liquid collection component before and after the film-forming liquid is injected.

[0019] The needle injection angle and position adjustment assembly includes but is not limited to basic parts such as a needle rotating device, a needle telescopic device, and a needle moving device along the axial direction of the drum rotation, which can realize the function of arbitrarily adjusting the shear force between the liquid and the surface of the film-forming substrate when the liquid is injected. When the substrate rotation speed is not adjusted, that is, when a fixed centrifugal field is maintained, if the shear force of liquid injection needs to be increased, the needle can be pointed in the direction opposite to the substrate rotation; when the shear force of liquid injection needs to be reduced, the needle can be pointed in the direction of the substrate rotation. The needle telescopic device can adjust the distance between the needle and the surface of the film-forming substrate. Due to different liquid flow rates, different liquid components and viscosities, the length and shape of the arc of the liquid column ejected from the needle are also different. By adjusting the needle telescopic device, the optimal needle injection distance can be obtained; the needle moving device along the axial direction of the drum rotation can control the position of the needle injected on the surface of the film-forming substrate, thereby controlling the liquid film distribution on the rotating substrate, and finally adjusting the film-forming area on the substrate.

[0020] The film-forming liquid booster assembly pressurizes the liquid and passes it into the needle, so that the liquid flowing out of the needle forms a thin column. The liquid booster assembly can adjust the liquid injection speed and the arc of the needle port liquid column by adjusting the liquid pressure.

[0021] The residual liquid collection component before and after the film-forming liquid is injected. At the beginning stage of the film-forming liquid injection, since the liquid flow in the liquid pipeline and the needle needs a certain time to reach a stable flow state when it is started, during this period, the liquid injected from the needle is unstable. If it is directly injected or dripped onto the surface of the film-forming substrate, it will cause uneven distribution of the film; similarly, in the stage of stopping the liquid injection, since the liquid flow in the liquid pipeline and the needle needs a certain time to reach a completely stopped flow state when it stops, during this period, the needle is prone to dripping. If it is directly dripped onto the surface of the film-forming substrate, it will also cause uneven distribution of the film. Therefore, a residual liquid collection component before and after the film-forming liquid is injected is required.

[0022] The residual liquid collection components before and after the film-forming liquid is injected can be, but are not limited to, a fixed residual liquid collection tank, a movable residual liquid collection tank, residual liquid absorbent cotton, and a residual liquid recovery tube. The working principle of the fixed residual liquid collection tank is: two fixed residual liquid collection tanks are fixed on the two edges of the film-forming area through the fixed residual liquid collection tank bracket, which do not rotate with the drum or move with the needle. When the needle injection starts, the needle is first moved to the fixed residual liquid collection tank so that the fixed residual liquid collection tank can collect residual liquid. After the liquid column is stable, the needle begins to move out of the fixed residual liquid collection tank and injects it into the surface of the film-forming substrate. When the needle moves out of the film-forming area, it enters above the second fixed residual liquid collection tank, stops the injection, and the residual liquid falls into the second fixed residual liquid collection tank. The working principle of the movable residual liquid collection tank is: when the injection starts, the movable residual liquid collection tank moves to the bottom of the needle, and the liquid column enters the movable residual liquid collection tank. When the needle moves to the film-forming area, the movable residual liquid collection tank is removed, and the liquid column enters the surface of the film-forming substrate. When the injection is stopped, the movable residual liquid collection tank is moved to the bottom of the needle to collect the residual liquid. The working principle of the residual liquid collection cotton is: when the needle starts to inject and ends the injection of liquid, the droplets formed are usually hanging on the tip of the needle. Therefore, the needle is covered with absorbent cotton, leaving only the needle tip exposed. The absorbent cotton will automatically absorb the droplets without affecting the injection of the liquid. The working principle of the residual liquid recovery tube is: when the needle starts to inject and ends the injection of liquid, the droplets formed are usually hanging on the tip of the needle. Therefore, the needle tip is covered with a residual liquid recovery tube. The residual liquid recovery tube is connected to the absorption pump through a pipeline, and the absorption pump can effectively absorb and recover the droplets. The residual liquid recovery tube is used to recover the droplets, which can be used for multiple large-flow droplet recovery, and can be applied to various solvents with different viscosities. The device can also be used for automatic needle cleaning, and the cleaning liquid can be quickly recovered using the residual liquid recovery tube.

[0023] The purpose of the residual liquid collection components before and after the injection of the above four film-forming liquids is to collect the unstable liquid columns or droplets formed at the beginning and end of the needle injection to prevent them from falling directly onto the surface of the rotating substrate and affecting the film-forming effect.

[0024] The advantages and beneficial effects of the present invention include:

[0025] (1) The present invention adopts a needle injection method to form a liquid column, which can evenly inject the liquid into the surface of the film-forming substrate. The needle injection can effectively control the injection area and injection amount, thereby controlling the film-forming area and film thickness.

[0026] (2) The present invention adopts a needle angle adjustment component to adjust the injection angle, thereby realizing independent regulation of the shear rate and centrifugal field on the substrate surface during liquid injection. When the centrifugal field remains unchanged, the shear rate can be increased by pointing the needle in the direction opposite to the substrate rotation, while the shear rate can be reduced by pointing the needle in the direction forward of the substrate rotation.

[0027] (3) The present invention adopts a residual liquid collection device, which can collect unstable droplets or liquid columns formed at the start and end stages of liquid injection, thereby preventing the residual liquid from falling directly into the film-forming area. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 (a)-(b) is a schematic diagram of the basic structure of a simple film-forming liquid needle injection system in Example 1. Figure 1 (a) is a stereogram, and Figure 1 (b) is a cross-sectional diagram.

[0029] Figure 2 (a)-(b) is a schematic diagram of the basic structure of the film-forming liquid needle injection system with a fixed residual liquid collection tank in Example 2, wherein Figure 2 (a) is a stereogram and Figure 2 (b) is a cross-sectional diagram.

[0030] Figure 3 (a)-(b) is a schematic diagram of the basic structure of the film-forming liquid needle injection system with a movable residual liquid collection tank in Example 3. Figure 3 (a) is a stereogram, and Figure 3 (b) is a cross-sectional diagram.

[0031] Figure 4 (a)-(b) is a schematic diagram of the basic structure of an injection needle with residual liquid absorbing cotton in Example 4. Figure 4 (a) is a stereogram, and Figure 4 (b) is a cross-sectional diagram.

[0032] Figure 5 (a)-(b) is a schematic diagram of the basic structure of an injection needle with a residual liquid recovery tube according to Example 5, wherein Figure 5 (a) is a stereogram and Figure 5 (b) is a partial cross-sectional diagram.

[0033] The names of the components indicated by numbers in the accompanying drawings are as follows:

[0034] 1: Rotating drum; 2: Film-forming substrate; 3: Needle; 4: Device for moving the needle along the rotating axis of the drum; 5: Device for adjusting the injection angle of the needle; 6: Device for retracting the needle; 7: Liquid booster pump; 8: Fixed residual liquid collecting tank; 9: Fixed residual liquid collecting tank bracket; 10: Movable residual liquid collecting tank; 11: Collecting tank moving device; 12: Residual liquid absorbing cotton; 13: Residual liquid recovery pipe; 14: Sliding rod one; 15: Sliding rod two; 16: Pipeline. DETAILED DESCRIPTION

[0035] The drawings and embodiments described in this specification are further described in detail for specific implementations of the present invention. The following five embodiments are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0036] Example 1

[0037] As shown in Figure 1(a)-(b), in this embodiment, the basic structure of a simple film-forming liquid needle injection system includes: a rotating drum 1, a film-forming substrate 2, a needle 3 (stainless steel needle), a device for moving the needle along the rotating axis of the drum 4 (electric slide), a needle injection angle adjustment device 5 (reduction motor), a needle telescopic device 6 (electric telescopic table), a liquid booster pump 7, etc. Among them, the stainless steel needle is 50mm long, with an inner diameter of 300μm and an outer diameter of 2mm; the needle moving device 4 along the rotating axial direction of the drum is a ball screw moving slide with a width of 40mm and a stroke of 150mm. The needle moving device 4 along the rotating axial direction of the drum is equipped with a slide bar 14, which is in sliding cooperation with the needle moving device 4 along the rotating axial direction of the drum, and the length of the slide bar 14 is 210mm; the needle injection angle adjustment device 5 is equipped with a reduction stepper motor, one end of which is installed at the tail end of the slide bar 14, and the other end of the needle injection angle adjustment device 5 is installed with a needle telescopic device 6, which can drive the needle telescopic device 6 to rotate 360 ​​degrees; the needle telescopic device 6 is a T-screw electric telescopic needle fixing seat, which is used to drive the needle 3 to telescope, and its telescopic stroke is 30mm. The stainless steel needle 3 is installed on the needle telescopic device 6, and the needle 3 is connected to the liquid booster pump 7 through a pipeline, and the pipeline passes through the needle telescopic device 6 and the slide bar 14 in sequence.

[0038] The use process of this embodiment is as follows: a film-forming substrate 2 is arranged on the inner surface of the rotating drum 1, and the rotating drum 1 drives the film-forming substrate 2 to rotate at a set speed, and the external or internal heating is turned on to control the surface temperature of the film-forming substrate 2. The appropriate needle injection angle is adjusted by the needle injection angle adjustment device 5, and the set starting injection position is adjusted by the needle moving device 4 along the rotating axis of the drum, and the distance between the needle tip of the needle 3 and the film-forming substrate 2 is adjusted by the needle telescopic device 6. The liquid booster pump 7 is turned on to start injecting liquid, and the uniform centrifugal force field and shear force field generated by the rotation of the rotating drum 1 are used to spread the liquid on the surface of the film-forming substrate 2 as an annular liquid film. At the same time, the needle 3 is moved by the needle moving device 4 along the rotating axis of the drum according to the set film-forming area, so that the liquid film is evenly spread over the entire set film-forming area. The transformation from liquid film to solid film is completed by curing treatment, and a uniform nano-thickness film is formed in the set area on the surface of the film-forming substrate 2.

[0039] The features of this embodiment are as follows: liquid is injected by needle, which can be used for various organic and inorganic liquids, suitable for a wide range of viscosities, and has low requirements for the dispersion of film-forming materials; the direction of liquid injection can be adjusted by the needle injection angle adjustment device, and the shear rate and centrifugal force of the liquid injection and the rotating drum can be regulated by controlling the liquid injection speed and the rotating drum speed; the distance between the needle tip and the substrate can be adjusted by the needle telescopic device to achieve the best arc for liquid injection. The liquid injection position can be changed by the needle moving device along the rotating axis of the drum, and the liquid film area and the film-forming area can be accurately controlled.

[0040] Example 2

[0041] As shown in Figure 2(a)-(b), in this embodiment, the basic structure of a film-forming liquid needle injection system with a fixed residual liquid collection tank includes: a rotating drum 1, a film-forming substrate 2, a needle 3, a device for moving the needle along the rotating axis of the drum 4, a needle injection angle adjustment device 5, a needle telescopic device 6, a liquid booster pump 7, a fixed residual liquid collection tank 8, a fixed residual liquid collection tank bracket 9, etc. Among them, the stainless steel needle is 50mm long, with an inner diameter of 300μm and an outer diameter of 2mm; the needle moving device 4 along the rotating axial direction of the drum is a ball screw moving slide with a width of 40mm and a stroke of 150mm. The needle moving device 4 along the rotating axial direction of the drum is equipped with a slide bar 14, which is in sliding cooperation with the needle moving device 4 along the rotating axial direction of the drum, and the length of the slide bar 14 is 210mm; the needle injection angle adjustment device 5 is equipped with a reduction stepper motor, one end of which is installed at the tail end of the slide bar 14, and the other end of the needle injection angle adjustment device 5 is installed with a needle telescopic device 6, which can drive the needle telescopic device 6 to rotate 360 ​​degrees; the needle telescopic device 6 is a T-screw electric telescopic needle fixing seat, which is used to drive the needle 3 to telescope, and its telescopic stroke is 30mm. The stainless steel needle 3 is installed on the needle telescopic device 6, and the needle 3 is connected to the liquid booster pump 7 through a pipeline, and the pipeline passes through the needle telescopic device 6 and the slide bar 14 in sequence.

[0042] In addition, the fixed residual liquid collecting tank 8 is two stainless steel semicircular collecting tanks arranged in parallel, the outer radius of the semicircular collecting tank is 114mm, the shell thickness is 1.0mm, the collecting tank width is 4mm, and the collecting tank height is 5mm. The distance between the two fixed residual liquid collecting tanks 8 is 80mm, that is, the width of the film forming area is 80mm. The two ends of the fixed residual liquid collecting tank 8 are fixed in the rotating drum 1 by two right-angled fixed residual liquid collecting tank brackets 9. The center of the fixed residual liquid collecting tank 8 is concentric with the rotating drum 1, and the gap between the fixed residual liquid collecting tank 8 and the film forming substrate 2 is 2mm.

[0043] The use process of this embodiment is as follows: the film-forming substrate 2 is arranged on the inner surface of the rotating drum 1, and the rotating drum 1 drives the film-forming substrate 2 to rotate at a set speed, and the external or internal heating is turned on to control the surface temperature of the film-forming substrate 2. The appropriate injection angle of the needle 3 and the distance between the needle tip of the needle 3 and the film-forming substrate 2 are adjusted. The needle is moved to the top of one of the two fixed residual liquid collection tanks 8 by the needle moving device 4 along the rotating axis of the drum, and the liquid booster pump 7 is started. Liquid droplets begin to drip from the needle into the fixed residual liquid collection tank 8. When the liquid becomes a stable liquid column, the needle is moved into the film-forming area by the needle moving device 4 along the rotating axis of the drum, and the needle 3 is continued to be moved to the top of the second fixed residual liquid collection tank 8. The needle 3 is stopped from being moved, and the liquid booster pump 7 is turned off, and the residual liquid drips into the fixed residual liquid collection tank 8. The liquid film evenly covers the area between the two fixed residual liquid collection tanks 8, and the transformation from liquid film to solid film is completed by curing treatment, and a uniform nano-thickness film is formed in the set area on the surface of the film-forming substrate 2.

[0044] The features of this embodiment are as follows: a fixed residual liquid collection tank is added. When the needle injects the liquid, it is difficult to quickly shut off the liquid column at the beginning and end of the injection of the liquid. Therefore, unstable liquid columns or droplets are easily generated at the beginning and end of the injection. If they are directly injected or dripped into the surface of the film-forming substrate, the film distribution will be uneven. This embodiment introduces a simple fixed residual liquid collection tank, which can ensure that the liquid column in the film-forming area is evenly injected and the residual liquid will not fall into the film-forming area.

[0045] Example 3

[0046] As shown in Figure 3 (a)-(b), in this embodiment, the basic structure of a film-forming liquid needle injection system with a movable residual liquid collection tank includes: a rotating drum 1, a film-forming substrate 2, a needle 3, a needle moving device along the rotating axis of the drum 4, a needle injection angle adjustment device 5, a needle telescopic device 6, a liquid booster pump 7, a movable residual liquid collection tank 10, a collection tank moving device 11, etc.; wherein, the stainless steel needle is 50mm long, 300μm in inner diameter, and 2mm in outer diameter; the needle moving device 4 along the rotating axis of the drum is a ball screw movable slide with a width of 40mm and a stroke of 150m m, a slide bar 14 is installed on the needle moving device 4 along the rotation axis of the drum, and the slide bar 14 is in sliding cooperation with the needle moving device 4 along the rotation axis of the drum, and the length of the slide bar 14 is 210mm; the needle injection angle adjustment device 5 is equipped with a reduction stepper motor, one end of which is installed at the tail end of the slide bar 14, and the other end of the needle injection angle adjustment device 5 is installed with a needle telescopic device 6, and the needle injection angle adjustment device 5 can drive the needle telescopic device 6 to rotate 360 ​​degrees; the needle telescopic device 6 is a T-type lead screw electric telescopic needle fixing seat, which is used to drive the needle 3 to telescope, and its telescopic stroke is 30mm. A stainless steel needle 3 is installed on the needle telescopic device 6, and the needle 3 is connected to the liquid booster pump 7 through a pipeline, and the pipeline passes through the needle telescopic device 6 and the slide bar 14 in sequence.

[0047] In addition, the movable residual liquid collecting tank 10 is a stainless steel semicircular collecting tank, the outer radius of the semicircular collecting tank is 114mm, the shell thickness is 1.0mm, the width of the collecting tank is 4mm, the height of the collecting tank is 5mm, and the gap between the movable residual liquid collecting tank 10 and the film-forming substrate 2 is 2mm. The collecting tank moving device 11 is a ball screw moving slide, with a width of 40mm and a stroke of 150mm. The collecting tank moving device 11 is installed with a slide bar 15, which is in sliding cooperation with the collecting tank moving device 11. The length of the slide bar 15 is 250mm. The movable residual liquid collecting tank 10 is installed at the tail end of the slide bar 15, and follows the movement of the slide bar 15 to extend into the rotating drum 1.

[0048] The use process of this embodiment is as follows: a film-forming substrate 2 is arranged on the inner surface of the rotating drum 1, and the rotating drum 1 drives the film-forming substrate 2 to rotate at a set speed, and the external or internal heating is turned on to control the surface temperature of the film-forming substrate 2. Adjust the appropriate injection angle of the needle 3 and the distance between the needle tip of the needle 3 and the film-forming substrate 2. Move the movable residual liquid collection tank 10 to the edge of the set film-forming area through the collection tank moving device 11, and move the needle 3 to the top of the movable residual liquid collection tank 10 through the needle moving device 4 along the rotating axis of the drum. Start the liquid booster pump 7, and droplets begin to drip from the needle into the movable residual liquid collection tank 10. When the liquid becomes a stable liquid column, move the needle 3 into the film-forming area through the needle moving device 4 along the rotating axis of the drum. When the needle 3 moves to the other edge of the film-forming area, move the movable residual liquid collection tank 10 to the bottom of the needle 3, stop moving the needle, turn off the liquid booster pump 7, and the residual liquid drips into the movable residual liquid collection tank 10. The liquid film evenly covers the set film-forming area, and the liquid film is transformed into a solid film through a solidification process, forming a film with uniform nanometer-level thickness in the set area on the surface of the film-forming substrate 2 .

[0049] The features of this embodiment are: adding a movable collecting tank, the liquid injection area can be adjusted at will, and the residual liquid can be collected at the beginning and end of the needle injection. It can ensure that the liquid column in the film-forming area is evenly injected, and the position and width of the film-forming area can be changed at will.

[0050] Example 4

[0051] As shown in Fig. 4 (a)-(b), in this embodiment, the basic structure of an injection needle with residual liquid absorbent cotton includes: a needle 3, a needle moving device 4 along the rotating axial direction of the drum, a needle injection angle adjustment device 5, a needle telescopic device 6, residual liquid absorbent cotton 12, etc. Among them, the needle injection angle adjustment device 5 is equipped with a reduction stepping motor, one end of which is installed at the tail end of a slide bar 14, and the other end of the needle injection angle adjustment device 5 is installed to drive the needle telescopic device 6, and the needle injection angle adjustment device 5 can drive the needle telescopic device 6 to rotate 360 ​​degrees; the needle telescopic device 6 is a T-screw electric telescopic needle fixing seat, which is used to drive the needle 3 to telescope, and its telescopic stroke is 30mm. A stainless steel needle 3 is installed on the needle telescopic device 6, and the needle 3 is connected to a liquid booster pump 7 through a pipeline, and the pipeline passes through the needle telescopic device 6 and the slide bar 14 in turn. The needle 3 is made of polytetrafluoroethylene, with a length of 50mm, an inner diameter of 200μm, and an outer diameter of 2mm. The residual liquid absorbing cotton 12 is a highly absorbent polyvinyl alcohol sponge, which is a hollow cylindrical sponge with an inner diameter of 1.9 mm, an outer diameter of 10 mm, and a height of 10 mm. The residual liquid absorbing cotton 12 is sleeved on the needle 3, and one end thereof is flush with the needle tip of the needle 3.

[0052] The use process of this embodiment: at the beginning and end of liquid injection, the liquid flows out of the needle tip 3 at a slow speed, and will first gather at the needle tip to form droplets, then the volume of the droplets gradually increases, and finally falls. After installing the residual liquid absorption cotton 12, the droplets are directly absorbed by the sponge at the needle tip, thereby avoiding dripping into the film-forming area. As for the liquid column, its ejection speed is fast, and it will not stay at the needle tip and increase in volume, so the sponge does not absorb the liquid column.

[0053] The characteristics of this embodiment are: a simple and convenient method is used to absorb the residual liquid, which is suitable for rollers with small spaces and injection methods with small liquid flow rates. It can save space and effectively absorb a small amount of residual liquid.

[0054] Example 5

[0055] As shown in Fig. 5(a)-(b), in this embodiment, the basic structure of an injection needle with a residual liquid recovery tube includes: a needle 3, a needle moving device 4 along the rotating axis of the drum, a needle injection angle adjustment device 5, a needle telescopic device 6, a residual liquid recovery tube 13, etc. Among them, the needle injection angle adjustment device 5 is equipped with a reduction stepping motor, one end of which is installed at the tail end of a slide bar 14, and the other end of the needle injection angle adjustment device 5 is installed to drive the needle telescopic device 6, and the needle injection angle adjustment device 5 can drive the needle telescopic device 6 to rotate 360 ​​degrees; the needle telescopic device 6 is a T-screw electric telescopic needle fixing seat, which is used to drive the needle 3 to telescope, and its telescopic stroke is 30mm. A stainless steel needle 3 is installed on the needle telescopic device 6, and the needle 3 is connected to a liquid booster pump 7 through a pipeline, and the pipeline passes through the needle telescopic device 6 and the slide bar 14 in turn. The needle 3 is made of glass, with a needle length of 50mm, an inner diameter of 500um, and an outer diameter of 2mm. As shown in FIG. 5( b ), the residual liquid recovery tube 13 is in the shape of a tube with a combination of small holes and large holes and is made of glass. The residual liquid recovery tube 13 is sleeved on the needle 3 through a small hole at one end, and the other end of the residual liquid recovery tube 13 is a large hole. The needle tip of the needle 3 is retracted 0.5 mm toward the other end surface of the residual liquid recovery tube 13. The large hole forms a cavity of the residual liquid recovery tube 13, and the upper outer part of the cavity is connected to the pipeline 16.

[0056] The usage process of this embodiment is as follows: at the beginning and end of liquid injection, the liquid flows out of the needle tip of the needle 3 at a slow speed, and will first gather at the needle tip to form droplets, and then the volume of the droplets gradually increases. When the diameter of the droplets reaches the inner diameter of the residual liquid recovery tube 13, the droplets are sucked into the cavity of the residual liquid recovery tube 13 by the capillary action of the residual liquid recovery tube, and then pass through the pipeline 16 to connect the absorption pump, and use the absorption pump to absorb and recover the liquid in the cavity of the residual liquid recovery tube 13.

[0057] The features of this embodiment are: the residual liquid recovery tube is used to recover the droplets, which can be used for multiple large-flow droplet recovery and can be applied to various solvents with different viscosities. The device can also be used for automatic needle cleaning, and the cleaning liquid can be quickly recovered by using the residual liquid recovery tube.

[0058] The above are five preferred embodiments of the present invention, which are not intended to limit the present invention. The various components of the device may be improved and deformed in a number of ways, and such improvements and deformations without departing from the technical principles of the present invention should also be considered as the protection scope of the present invention.

Claims

1. A film-forming liquid injection device for centrifugal film formation, characterized in that: The device includes: a rotating drum, a film-forming substrate, a needle, a device for moving the needle along the rotating axis of the drum, a device for adjusting the injection angle of the needle, a needle telescopic device, and a film-forming liquid pressurizing component. The specific structure is as follows: A film-forming matrix is ​​arranged on the inner surface of the rotating drum, a slide bar 1 is installed on the device for moving the needle along the rotating axis of the drum, the slide bar 1 is in sliding cooperation with the device for moving the needle along the rotating axis of the drum, one end of a needle injection angle adjustment device is installed at the tail end of the slide bar 1, a needle telescopic device is installed at the other end of the needle injection angle adjustment device, and the needle injection angle adjustment device drives the needle telescopic device to rotate 360 ​​degrees; a needle is installed on the needle telescopic device, and the needle is connected to the film-forming liquid booster assembly through a pipeline, and the pipeline passes through the needle telescopic device and the slide bar 1 in sequence; It also includes a residual liquid collection component before and after the film-forming liquid is injected, including residual liquid absorption cotton or a residual liquid recovery tube; The residual liquid absorbing cotton is in the shape of a hollow cylinder, and is put on the needle, with one end of the residual liquid absorbing cotton flush with the needle tip; The residual liquid recovery tube is in the shape of a tube with a combination of small holes and large holes in a stepped hole. The residual liquid recovery tube is sleeved on the needle through the small hole at one end, and the other end of the residual liquid recovery tube is a large hole. The needle tip of the needle is retracted 0.3-1 mm toward the other end surface of the residual liquid recovery tube. The large hole forms a cavity of the residual liquid recovery tube, and the upper outer part of the cavity is connected to the absorption pump through a pipeline; Without adjusting the substrate rotation speed, the needle is directed to the direction opposite to the substrate rotation direction or to the direction forward of the substrate rotation direction through the needle injection angle adjustment device; the needle telescopic device adjusts the distance between the needle and the film-forming substrate surface, and the optimal needle injection distance is obtained by adjusting the needle telescopic device; the needle moves along the axial direction of the drum to control the position of the needle injected on the film-forming substrate surface, thereby controlling the liquid film distribution on the rotating substrate, and finally adjusting the film-forming area on the substrate; At the beginning stage of film-forming liquid injection, since it takes a certain time for the liquid flow in the liquid pipeline and the needle to reach a stable flow state at startup, during this period, the liquid injected from the needle is unstable. If it is directly injected or dripped onto the surface of the film-forming substrate, it will cause uneven distribution of the film; similarly, at the stage of stopping liquid injection, since it takes a certain time for the liquid flow in the liquid pipeline and the needle to reach a completely stopped flow state when it stops, during this period, the needle is prone to dripping. If it is directly dripped onto the surface of the film-forming substrate, it will also cause uneven distribution of the film; therefore, the unstable liquid column or droplets formed at the beginning and end of the needle injection are collected by the residual liquid collection component before and after the film-forming liquid injection to prevent them from falling directly onto the surface of the rotating substrate and affecting the film-forming effect; The shape of the needle tip is linear or curved, and its length ranges from 0.1 mm to 1000 mm; the cross-sectional shape of the needle hole is circular, elliptical, polygonal, or various regular or irregular shapes transformed from the above shapes; the aperture of the needle hole or the longest dimension of the internal connecting line of the hole cross section ranges from 1 μm to 10 cm; the needle tip material includes metal, inorganic non-metallic material or organic polymer material.

2. The membrane-forming liquid injection device for centrifugal membrane formation according to claim 1, characterized in that: The length of the needle tip ranges from 5 mm to 100 mm; the aperture of the pinhole or the longest dimension of the internal connecting line of the hole section ranges from 10 μm to 2 mm; the metal is made of stainless steel, nickel, copper, gold or silver, the inorganic non-metallic material is made of glass, quartz, ceramic or graphite, and the organic polymer material is made of polytetrafluoroethylene, polypropylene, polycarbonate, ABS plastic, polyvinyl chloride or polyethylene terephthalate.

3. The membrane-forming liquid injection device for centrifugal membrane formation according to claim 1, characterized in that: The needle injection angle adjustment device includes a stepping motor, a DC motor or a servo motor.

4. The membrane-forming liquid injection device for centrifugal membrane formation according to claim 1, characterized in that: The needle telescopic device includes a manual telescopic rod, an electric slide module or a pneumatic telescopic rod, the needle axial movement device along the rotating drum includes a manual slide, an electric slide or a pneumatic slide, and the film-forming liquid boosting component adopts a syringe, an injection pump, a peristaltic pump, a diaphragm pump or a liquid pump.

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