Hot pressing method of micro-fluidic chip and micro-fluidic chip

Abstract

The invention belongs to the technical field of micro-fluidic chips, and particularly relates to a hot pressing method of a micro-fluidic chip and the micro-fluidic chip. The hot-pressing method of the micro-fluidic chip comprises the following steps: making a mold and preparing a forming mold, the forming mold comprises the following steps: preparing a female mold and at least two male molds, and the heights of the at least two male molds are different; detachably connecting the female die with one of the male dies; heating is conducted, specifically, the male die abuts against the blank, and the blank, the male die and the female die are heated; hot pressing is conducted, so that hot pressure exists between the male die and the blank, the male die extrudes the blank, the blank copies the shape of the male die, and the blank is machined into the micro-fluidic chip; demolding, cooling the micro-fluidic chip, the female mold and the male mold, and separating the micro-fluidic chip from the male mold. According to the invention, different micro-channel chips can be processed through one set of forming die, so that the preparation cost for preparing various different micro-channel chips is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of microfluidic chips, and in particular relates to a hot pressing method for a microfluidic chip and a microfluidic chip. Background Art

[0002] Microfluidic chips are small devices that integrate complex fluid control systems. They are usually composed of multiple micrometer- or nanometer-scale channels, pumps, and valves, which can precisely control the flow of liquids. By processing liquid samples in tiny channels, it can improve analysis efficiency, reduce sample volume, and provide high-resolution results. They are widely used in biomedical diagnosis, drug development, environmental monitoring, and chemical analysis.

[0003] At present, the manufacturing methods of microfluidic chips include soft lithography, hot pressing, inkjet printing and laser micromachining. Among them, glass precision molding technology is relatively mature, and hot forming is suitable for mass-production and low-cost manufacturing of glass microfluidic chips. The production of glass microfluidic chips has very high requirements on the surface accuracy of the molding mold. The surface quality of the molding mold determines the quality of the microfluidic channel after processing. The material of the molding mold is usually high temperature resistant material, such as tungsten carbide, silicon carbide, glassy carbon, etc. These materials are hard and brittle, and are often processed by ultrasonic milling.

[0004] However, the cost of ultrasonic milling is high, especially when preparing different microfluidic chips, it is necessary to process multiple sets of molding molds separately, which often leads to excessively high preparation costs of microfluidic chips. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a hot pressing method for a microfluidic chip, aiming to solve the problem of how to reduce the preparation cost when processing different microfluidic chips.

[0006] To achieve the above purpose, the technical solution adopted in this application is: In a first aspect, a method for hot pressing a microfluidic chip is provided, comprising the following steps: Molding, preparing a molding mold, the molding mold comprising: a mother mold and a male mold matched with the mother mold, at least two of the male molds are prepared, and at least two of the male molds have different heights; the mother mold is detachably connected to one of the male molds; Heating, placing the male mold relative to the blank, and heating the blank, the male mold and the female mold; Hot pressing, so that there is hot pressure between the convex mold and the blank, so that the convex mold squeezes the blank, and the blank replicates the shape of the convex mold, so that the blank is processed into a microfluidic chip; Demolding, cooling the microfluidic chip, and separating the microfluidic chip and the convex mold.

[0007] In some embodiments, the punch is in the form of a sheet, and the molding step includes machining a positioning groove on the mother mold, the shape of the positioning groove being adapted to the shape of the punch, inserting and positioning the punch in the positioning groove, and making part of the punch located in the positioning groove, and making another part of the punch abut against the blank.

[0008] In some embodiments, the punch is arranged in a zigzag shape.

[0009] In some embodiments, the master mold has a mounting surface, the positioning groove is opened on the mounting surface, and the molding step further includes a polishing step, and the polishing step includes: polishing the mounting surface; The two side surfaces of the punch and the end surface used for hot pressing the blank are polished.

[0010] In some embodiments, the positioning groove runs through the two opposite surfaces of the mother mold, and the hot pressing method of the microfluidic chip also includes preparing a pressing plate, which is arranged on one side of the mother mold and covers the positioning groove, and the convex mold is located on the other side of the mother mold.

[0011] In some embodiments, the master mold is processed by using an electric spark wire cutting process to machine the positioning groove on the master mold; and the punch is machined on the template by using the electric spark wire cutting process.

[0012] In some embodiments, the electric spark wire discharge process is repeated multiple times.

[0013] In some embodiments, there are two positioning grooves, and the shapes of the extension paths of the two positioning grooves are different, wherein the shapes of the two punches are respectively adapted to the shapes of the two positioning grooves.

[0014] In some embodiments, the heating step includes preparing a sleeve and a heating tube, the blank, the master mold and the punch are placed and positioned in the sleeve, and the heating tube is arranged along the circumference of the sleeve and is used to heat the blank, the master mold and the punch.

[0015] In a second aspect, a microfluidic chip is provided, wherein the microfluidic chip is prepared by a hot pressing method of the microfluidic chip.

[0016] The beneficial effect of the present application is that by preparing a mother mold and at least two convex molds, different convex molds are detachably connected to the mother mold, so that they can be combined to form different molding molds, and then the blanks are hot-pressed by the molding molds, so that different blanks can be processed into different microfluidic chips respectively. Different microfluidic chips can be processed by a set of molding molds, avoiding the simultaneous development of two sets of molding molds, and reducing the preparation cost of preparing a variety of different microfluidic chips. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or exemplary technical descriptions will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 is a flow chart of a hot pressing method for a microfluidic chip provided in an embodiment of the present application; Figure 2 is an exploded schematic diagram of a forming die, a sleeve and a blank provided in another embodiment of the present application; Figure 3 yes Figure 2 An exploded schematic diagram of a male mold and a female mold of a molding mold; Figure 4 yes Figure 1 Schematic cross-sectional view of the forming die, sleeve and blank after assembly.

[0019] Among them, the reference numerals in the figure are: 10. Pressing plate; 20. Blank; 30. Forming die; 31. Punch; 32. Mother die; 40. Sleeve; 50. Heating tube; 322. Mounting surface; 321. Positioning groove. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present application.

[0021] It should be noted that when a component is referred to as being "fixed on" or "disposed on" another component, it may be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it may be directly or indirectly connected to the other component. The orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances. The terms "first" and "second" are only used for the purpose of convenience of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0022] See also Figures 1 to 3 The present application embodiment provides a hot pressing method for a microfluidic chip, which is used to prepare a blank 20 into a microfluidic chip. The blank 20 can be a thermoplastic material, such as plastic or glass. In this embodiment, the blank 20 is a plate of glass. In other embodiments, it can also be selected according to actual conditions, which is not limited here. Microfluidic chips have the characteristics of high precision, good chemical inertness, good optical transparency and precise fluid control ability, so they are widely used in biomedicine, chemical analysis, environmental monitoring, drug development, food safety and other fields.

[0023] See also Figures 1 to 3 The hot pressing method of the microfluidic chip comprises the following steps: S1: Molding, preparing a molding mold 30, the molding mold 30 includes a mother mold 32 and a male mold 31 matched with the mother mold 32, the mother mold 32 can be used to fix the male mold 31, and the male mold 31 is used to hot press the blank 20. Molding includes the following steps: S11: preparing a master mold 32 , the master mold 32 is in a plate shape as a whole, and the material of the master mold 32 can be a high temperature resistant hard material, such as tungsten carbide.

[0024] S12: preparing a convex mold 31, wherein at least two convex molds 31 are prepared, and at least two convex molds 31 have different heights; detachably connecting the female mold 32 to one of the convex molds 31, and after the convex mold 31 is connected to the female mold 32, the height of the convex mold 31 is arranged along the vertical direction; It is understandable that when the convex molds 31 are placed on the same horizontal plane, the heights of the convex molds 31 are different. When the convex molds 31 are mounted on the mother mold 32, the distances between the end surface of the convex mold 31 used for hot pressing the blank 20 and the surface of the mother mold 32 on which the convex mold 31 is mounted are also different, so that the molding molds 30 with different hot pressing depths can be formed, and microchannels with different depths can be hot pressed on the blank 20, and then at least two different microfluidic chips can be prepared using a set of molding molds 30.

[0025] The microchannel may be a micro-nano structure, and its size is micrometer-level and / or nanometer-level. In the present application, the microchannel is a groove structure, and its groove width may be 0.2 mm.

[0026] S2: Heating, setting the punch 31 relative to the blank 20, or directly placing the punch 31 against the blank 20, heating the blank 20, the punch 31 and the die 32; the blank 20 can be fixed on a workbench, with the punch 31 located above the blank 20, or the punch 31 and the die 32 can be fixed on a workbench, with the blank 20 located above the punch 31. In this embodiment, the punch 31 is located above the blank 20. In other embodiments, the selection can be made according to actual conditions and is not limited here.

[0027] See also Figure 4 , the blank 20 and the forming mold 30 can be heated by a heating structure, and the heating structure can transfer heat by heat conduction or heat radiation, for example, the heating structure can generate heat by an infrared heating tube. The blank 20 can be heated to a temperature near its glass transition point by the heating structure, for example, 20 degrees Celsius higher than the glass transition point, so as to soften the blank 20 and improve the plasticity of the blank 20, and the heating environment of the blank 20 can be a vacuum environment or an inert gas environment, so as to avoid oxidation of the blank 20, and the vacuum degree of the vacuum environment can be 0.001Pa, and the inert gas can be nitrogen or argon.

[0028] S3: hot pressing, so that there is hot pressure between the convex mold 31 and the blank 20, for example, hot pressure is applied to the blank 20 on the mother mold 32, so that the convex mold 31 squeezes the blank 20, and the blank 20 copies the shape of the convex mold 31, and a microchannel is processed on the blank 20, and finally the blank 20 is processed into a microfluidic chip; It can be understood that when the blank 20 is located below the punch 31, the direction of the hot pressure is vertically downward and points to the blank 20. The hot pressure drives the punch 31 to move downward to replicate the shape of the punch 31 on the blank 20 and maintain the pressure for a certain period of time to improve the replication accuracy of the blank 20 on the punch 31.

[0029] When the blank 20 is located above the punch 31, the direction of the heat pressure is vertically downward and directed toward the punch 31. Figure 4 The hot pressure drives the blank 20 to move downward to copy the shape of the punch 31 onto the blank 20, and the temperature and pressure are kept for a certain time to improve the copying accuracy of the blank 20 to the punch 31, which can be 5 minutes.

[0030] S4: demoulding, cooling the microfluidic chip, the mother mold 32 and the male mold 31, and separating the microfluidic chip and the male mold 31; It is understandable that nitrogen gas with a relatively low temperature can be blown toward the hot-pressed blank 20 and the forming mold 30, thereby achieving the cooling of the blank 20 and the forming mold 30 and obtaining a microfluidic chip. The temperature range of the nitrogen gas can be -100 degrees Celsius to 0 degrees Celsius.

[0031] See also Figures 1 to 3The hot pressing method of the microfluidic chip provided in the embodiment of the present application prepares a mother mold 32 and at least two convex molds 31, and different convex molds 31 are detachably connected to the mother mold 32, so that different molding molds 30 can be combined to form, and then the blanks 20 are hot pressed by the molding molds 30, so that different blanks 20 can be processed into different microfluidic chips respectively. Different microfluidic chips can be processed by a set of molding molds 30, avoiding the simultaneous development of two sets of molding molds 30, thereby reducing the preparation cost of preparing a variety of different microfluidic chips.

[0032] It is understandable that the convex mold 31 on the mother mold 32 is replaced with another convex mold 31 of different height, and the heating, hot pressing and demolding steps are repeated on another blank 20, that is, only the corresponding convex mold 31 needs to be installed on the mother mold 32, and the corresponding microfluidic chip can be processed, so that two different microfluidic chips can be processed by a set of molding molds 30. Of course, the number of convex molds 31 can also be set to three or more, and the heights of the convex molds 31 are different, which is not limited here and can be selected according to actual conditions.

[0033] It is understandable that the materials of the female mold 32 and the male mold 31 can be tungsten carbide, silicon nitride or glassy carbon.

[0034] See also Figures 1 to 3 In some embodiments, the male mold 31 is in the form of a sheet, and the molding step further includes machining a positioning groove 321 on the female mold 32. The shape of the positioning groove 321 matches the shape of the male mold 31. For example, when the male mold 31 is in the form of a flat plate, the extension path of the positioning groove 321 is a straight line. The positioning groove 321 can be a blind groove structure or a through groove structure. The male mold 31 can be inserted into and positioned in the positioning groove 321, that is, part of the male mold 31 is located in the positioning groove 321, and the other part of the male mold 31 is exposed and can abut the blank 20.

[0035] Optionally, the punch 31 is in the shape of a thin sheet, and the positioning groove 321 can realize the detachable connection between the punch 31 and the mother mold 32. The exposed part of the punch 31 can be used to hot press the blank 20, and the exposed parts of the punches 31 with different heights have different heights, so that microchannels of different depths can be hot pressed on the blank 20.

[0036] See also Figures 1 to 3 In some embodiments, the punch 31 is arranged in a circuitous shape, and the shape of the positioning groove 321 is adapted to the circuitous shape of the punch 31 .

[0037] See also Figures 1 to 3It can be understood that the extension path of the punch 31 is in a tortuous snake shape, and there is a small radius bending corner, and the curvature radius at the corner can range from 0.1 to 2 mm. The molding die 30 is set as a split type, and the mother mold 32 and the punch 31 can be processed separately, and then the punch 31 and the mother mold 32 are assembled. When the mother mold 32 and the punch 31 are processed separately, any surface of the mother mold 32 or the punch 31 can be effectively processed, such as effective polishing, to avoid the problem that the right angle edge at the connection between the punch 31 and the mother mold 32 is not easy to polish, and when processing the small radius bending position of the punch 31, there is also enough feed space, so that a high-precision mother mold 32 and a punch 31 that meets the shape requirements can be processed, and the separate processing does not require complex procedures and the use of complex tools, which reduces the processing cost and improves the processing efficiency.

[0038] Optionally, when the punch 31 hot presses the blank 20, a microfluidic channel of a corresponding shape can be processed on the blank 20, and the serpentine positioning groove 321 can increase the contact area between the mother mold 32 and the punch 31, and can realize the connection between the punch 31 and the mother mold 32 in multiple directions, thereby improving the stability and reliability of the connection between the mother mold 32 and the punch 31. During the hot pressing process, the punch 31 can apply uniform force to the blank 20 at multiple different positions. The multi-point force in the longitudinal and transverse directions can make the blank 20 uniformly stressed as a whole, thereby improving the hot pressing accuracy of the microfluidic channel.

[0039] In some embodiments, the mother mold 32 has a mounting surface 322. During the hot pressing process, when the blank 20 is located below the punch 31, the mounting surface 322 is set downward. When the blank 20 is located above the punch 31, the mounting surface 322 is set upward. The positioning groove 321 is opened on the mounting surface 322, and the molding step also includes a polishing step.

[0040] S13: The polishing step includes: S131: polishing the mounting surface 322; S132: Polishing the two side surfaces of the punch 31 and the end surface of the hot-pressed blank 20.

[0041] See also Figures 2 to 4 Optionally, an ultrasonic polishing process can be used to polish the mounting surface 322 and the punch 31 separately, while the mother mold 32 and the punch 31 are polished separately, which can improve the convenience and polishing effect of polishing, avoid the formation of a polishing dead angle at the connection between the punch 31 and the mother mold 32, that is, avoid the formation of an unpolished area in the right-angle area between the side surface of the punch 31 and the mounting surface 322, thereby improving the polishing accuracy of the molding mold 30, and further improving the hot pressing accuracy of the blank 20.

[0042] See also Figures 2 to 4In some embodiments, the positioning groove 321 passes through the two opposite surfaces of the mother mold 32. The hot pressing method of the microfluidic chip also includes preparing a pressing plate 10, setting the pressing plate 10 on one side of the mother mold 32 and covering the positioning groove 321, and the punch 31 is located on the other side of the mother mold 32. Hot pressure is applied to the pressing plate 10 so that the blank 20 replicates the shape of the punch 31.

[0043] By penetrating the positioning groove 321 through the two side surfaces of the mother mold 32 , it is convenient to process the mother mold 32 , thereby improving the convenience of processing the positioning groove 321 .

[0044] Optionally, when the punch 31 is located above the blank 20 , the punch 31 located in the positioning groove 321 can be limited by the pressing plate 10 , and the female mold 32 and the punch 31 can be driven by the pressing plate 10 to move toward the blank 20 as a whole.

[0045] When the blank 20 is located above the punch 31 , the pressing plate 10 covers the blank 20 , the mother mold 32 is positioned on the workbench, the punch 31 is limited by the workbench below, and the blank 20 can be driven to move toward the punch 31 as a whole through the pressing plate 10 .

[0046] In some embodiments, the master mold 32 is processed by using an electric spark wire process to form a positioning groove 321 on the master mold 32. The electric spark wire process can also be used to process a male mold 31 on the template.

[0047] Optionally, due to the diameter of the cutter head, milling cannot process small radius corners or curved surfaces, while the electric spark wire cutting process can process small radius corners, such as a corner with a radius of 0.2 mm. Therefore, the present application can reduce the processing difficulty of the master mold 32 and the punch 31 and improve the processing convenience.

[0048] See also Figures 2 to 4 In some embodiments, the mother mold 32 or the punch 31 is placed in oil, the electric pulse interval of the EDM process is 10 μs, and the oil speed of the oil is 7 L / min, so as to process the mother mold 32 or the punch 31 that meets the requirements. The EDM process can process high-hardness materials and complex shapes, and is suitable for the complex shape processing requirements of the positioning groove 321 and the punch 31, ensuring the accuracy of the molding mold 30 and improving the molding effect of the microchannel.

[0049] Optionally, after the completion of the electrical discharge machining, the surfaces of the mother mold 32 and each of the punches 31 need to be polished and cleaned with alcohol ultrasonic vibration.

[0050] See also Figures 2 to 4 In some embodiments, the EDM process is repeated multiple times to perform multiple finishing cuts on the mother mold 32 and the punch 31 to improve the machining accuracy of the mother mold 32 and the punch 31.

[0051] Optionally, in order to improve the surface quality and assembly accuracy of the female mold 32 and the male mold 31, the number of finishing cutting is 10 times, and the surface roughness of the female mold 32 and the male mold 31 can reach 70nm.

[0052] See also Figures 2 to 4 In some embodiments, two positioning grooves 321 are provided, and the shapes of the extension paths of the two positioning grooves 321 are different, wherein the shapes of the two punches 31 are respectively adapted to the shapes of the two positioning grooves 321 .

[0053] Optionally, the shape of the extension path of one of the positioning grooves 321 can be a straight line, and the corresponding shape of the punch 31 is a straight-line punch 31; and the shape of the extension path of the other positioning groove 321 can be an arc, and the corresponding shape of the punch 31 is an arc-shaped punch 31, so that punches 31 of different shapes can be assembled on a mother mold 32, and different punches 31 can simultaneously hot-press microchannels of different shapes on the blank 20, thereby reducing the preparation cost of different microfluidic chips.

[0054] See also Figures 2 to 4 In some embodiments, the heating step also includes preparing a heating structure, which includes a sleeve 40 and a heating tube 50, the blank 20, the punch 31 and the die 32 are placed and positioned on the sleeve 40, and the heating tube 50 is arranged along the circumference of the sleeve 40 and is used to heat the blank 20, the die 32 and the punch 31.

[0055] Optionally, the heating tube 50 may be a ceramic heating tube or an infrared heating tube, which is not limited here and can be selected according to actual conditions. The sleeve 40 and the circumferentially arranged heating tubes 50 are used to uniformly heat the blank 20, the mother mold 32 and the punch 31, thereby avoiding uneven heating of the blank 20 due to local overheating and improving processing efficiency and molding accuracy.

[0056] See also Figures 2 to 4 The hot pressing method of the microfluidic chip provided in the embodiment of the present application is intended to improve the processing efficiency of the glass microfluidic chip and reduce its manufacturing cost, and has the following characteristics: Flexible combination, the molding die 30 is a split die, and different molding dies 30 can be formed by combining the same mother die 32 by replacing the convex dies 31 of different heights, so that microchannels of different depths can be processed on the blank 20 .

[0057] To facilitate polishing, the mother mold 32 and the male mold 31 can be disassembled, so that the mother mold 32 and the male mold 31 can be polished separately. The separate polishing of the two components can produce a microfluidic chip with high surface quality.

[0058] Reduce the difficulty of processing. Electric spark wire cutting can process small radius corners, reducing the difficulty and cost of processing.

[0059] See also Figures 2 to 4 The present invention also proposes a microfluidic chip, which is prepared by the hot pressing method of the above-mentioned microfluidic chip. For the specific steps of the hot pressing method of the microfluidic chip, please refer to the above-mentioned embodiment. Since the microfluidic chip adopts all the technical solutions of all the above-mentioned embodiments, it also has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0060] Optionally, a precision molding machine can be used to implement a hot pressing method for the microfluidic chip, and a glass microfluidic chip can be manufactured through heating, hot pressing, cooling, and demolding.

[0061] The above are only optional embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A hot pressing method for a microfluidic chip, characterized in that: The steps include: Molding, preparing a molding mold, the molding mold comprising: a mother mold and a male mold matched with the mother mold, at least two of the male molds are prepared, and at least two of the male molds have different heights; the mother mold is detachably connected to one of the male molds; Heating, placing the male mold relative to the blank, and heating the blank, the male mold and the female mold; Hot pressing, so that there is hot pressure between the convex mold and the blank, so that the convex mold squeezes the blank, and the blank replicates the shape of the convex mold, so that the blank is processed into a microfluidic chip; Demolding, cooling the microfluidic chip, and separating the microfluidic chip and the convex mold.

2. The hot pressing method of the microfluidic chip according to claim 1, characterized in that: The punch is in sheet shape, and the molding step includes machining a positioning groove on the mother mold, the shape of the positioning groove matches the shape of the punch, inserting and positioning the punch in the positioning groove, making part of the punch located in the positioning groove, and making another part of the punch abut against the blank.

3. The hot pressing method of the microfluidic chip according to claim 2, characterized in that: The convex mold is arranged in a circuitous shape.

4. The hot pressing method of the microfluidic chip according to claim 2, characterized in that: The mother mold has a mounting surface, the positioning groove is opened on the mounting surface, and the molding step also includes a polishing step, and the polishing step includes: polishing the mounting surface; The two side surfaces of the punch and the end surface used for hot pressing the blank are polished.

5. The hot pressing method of the microfluidic chip according to claim 2, characterized in that: The positioning groove runs through the two opposite surfaces of the mother mold. The hot pressing method of the microfluidic chip also includes preparing a pressing plate, which is arranged on one side of the mother mold and covers the positioning groove. The convex mold is located on the other side of the mother mold.

6. The hot pressing method for a microfluidic chip according to any one of claims 2 to 5, characterized in that: The master mold is processed by using an electric spark wire cutting process to form the positioning groove on the master mold; and the male mold is processed on the template by using the electric spark wire cutting process.

7. The hot pressing method of the microfluidic chip according to claim 6, characterized in that: The electric spark wire walking process is repeated multiple times.

8. The hot pressing method for a microfluidic chip according to any one of claims 2 to 5, characterized in that: There are two positioning grooves, and the shapes of the extension paths of the two positioning grooves are different, wherein the shapes of the two punches are respectively adapted to the shapes of the two positioning grooves.

9. The hot pressing method for a microfluidic chip according to any one of claims 1 to 5, characterized in that: The heating step includes preparing a sleeve and a heating tube, wherein the blank, the mother mold and the male mold are placed and positioned in the sleeve, and the heating tube is arranged along the circumference of the sleeve and is used to heat the blank, the mother mold and the male mold.

10. A microfluidic chip, characterized in that: The microfluidic chip is prepared by the hot pressing method of the microfluidic chip described in any one of claims 1 to 9.

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