Imprinting mold for forming hydrogel microstructure

Abstract

The utility model provides an imprint die for forming a hydrogel microstructure, which comprises an upper die holder, a lower die holder and a lower die holder, the mold core is fixed in the groove, and a pattern for forming a hydrogel microstructure is processed at the bottom of the mold core; a first-stage fluid channel is machined in the upper die base, a second-stage fluid channel is machined in the die core, and the first-stage fluid channel is communicated with the second-stage fluid channel. The lower die base and the upper die base are arranged in parallel, and a forming platform is arranged at the top of the lower die base; the utility model relates to the technical field of imprint molds, the mold core is made of flexible materials, the hydrogel structure can be gradually stripped through the elastic deformation of the mold core during demolding instead of forced hard pulling, the demolding stress can be greatly reduced through the soft stripping mode, and the microstructure is effectively prevented from being broken, torn or permanently deformed in the demolding process.

Description

Technical Field

[0001] This utility model relates to the field of embossing mold technology, and in particular to an embossing mold for forming hydrogel microstructures. Background Technology

[0002] Hydrogel materials have wide applications in tissue engineering, drug release, and flexible sensing due to their excellent biocompatibility, high water content, and tunable physicochemical properties. The preparation of microstructured hydrogels usually requires micro-nano fabrication technology, among which imprinting technology has attracted widespread attention due to its advantages such as high efficiency, low cost, and mass production capability.

[0003] Currently, misalignment is prone to occur during the molding process of hydrogel microstructure imprinting molds, resulting in misalignment or distortion of the microstructure pattern. During demolding, the strong adhesion of hydrogel can easily cause structural damage or destruction. Utility Model Content

[0004] The purpose of this invention is to provide an imprinting mold for forming hydrogel microstructures, which prevents the hydrogel structure from being damaged during demolding.

[0005] This utility model provides an imprinting mold for forming hydrogel microstructures, comprising:

[0006] The upper mold base has a groove machined on its bottom;

[0007] A mold core is fixed in the groove, and the bottom of the mold core is processed with a pattern for molding hydrogel microstructures;

[0008] The upper mold base has a primary fluid channel machined inside, and the mold core has a secondary fluid channel machined inside, and the primary fluid channel and the secondary fluid channel are connected.

[0009] A lower mold base is provided, which is arranged parallel to the upper mold base, and a forming platform is provided on the top of the lower mold base;

[0010] The alignment guide mechanism includes a pin disposed on the upper mold base and a slot disposed on the lower mold base and adapted to the pin;

[0011] A locking element is provided at the bottom of the lower mold base and is used to apply a locking force to the upper mold base and the lower mold base after the mold is closed.

[0012] Preferably, the locking element includes:

[0013] A backing plate is located on the bottom surface of the lower mold base;

[0014] Two threaded columns are respectively vertically fixed to both sides of the upper surface of the pad;

[0015] Two arc-shaped pressure plates are respectively fitted onto the corresponding threaded columns;

[0016] A nut is threadedly connected to the top end of the threaded column;

[0017] The upper mold base has slots on both sides that are adapted to the inner arc surface of the arc-shaped pressure plate; tightening the nut can drive the arc-shaped pressure plate to move downward and press it into the slots.

[0018] Preferably, the pad is fixedly connected to the bottom surface of the lower mold base by screws or locating pins.

[0019] Preferably, the forming platform is mounted on the upper surface of the lower mold base via a threaded rod, and the threaded rod engages with a threaded hole on the lower mold base.

[0020] Preferably, the mold core is made of a flexible material, namely polydimethylsiloxane.

[0021] Preferably, the inlet end of the primary fluid channel is connected to a fluid interface.

[0022] Preferably, the end of the pin is tapered, and the entrance of the slot is provided with a matching tapered guide surface.

[0023] Preferably, the outlet end of the secondary fluid channel extends to the microstructure pattern at the bottom of the mold core.

[0024] This invention provides an imprinting mold for forming hydrogel microstructures:

[0025] The core is made of flexible material, which can gradually peel off the hydrogel structure through its own elastic deformation (such as bending and stretching) during demolding, rather than forcibly pulling it. This "soft peeling" method can greatly reduce demolding stress and effectively prevent the microstructure from breaking, tearing or permanently deforming during demolding.

[0026] The secondary fluid channel and the primary fluid channel of the mold core are connected. When the mold is closed, the gas can be discharged through the "channel" to prevent the generation of air bubbles. Compressed air or release agent can be added during demolding to assist in demolding. Attached Figure Description

[0027] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0028] Figure 1This is a schematic diagram of the structure of this utility model;

[0029] Figure 2 This is a schematic diagram of the structure of the upper mold base, mold core, lower mold base, and forming platform in this utility model;

[0030] Figure 3 This is an assembly drawing of the locking component in this utility model;

[0031] Figure 4 This is a cross-sectional view of the upper mold base in this utility model;

[0032] Figure 5 This is a schematic diagram of the upper mold base, groove, and fluid interface in this utility model;

[0033] Figure 6 This is a schematic diagram of the assembly of the forming platform and the threaded rod in this utility model.

[0034] Explanation of reference numerals in the attached figures:

[0035] 1-Upper mold base, 11-Groove, 12-Primary fluid channel, 13-Fluid interface, 14-Slot, 2-Mold core, 21-Secondary fluid channel, 3-Lower mold base, 4-Forming platform, 41-Threaded rod, 51-Pin, 52-Slot, 6-Locking component, 61-Pad, 62-Threaded column, 63-Arc-shaped pressure plate, 64-Nut. Detailed Implementation

[0036] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0037] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0038] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0039] In this embodiment, as Figure 1 and Figure 2 As shown, an impression mold for forming hydrogel microstructures includes: an upper mold base 1 with a groove 11 machined on its bottom; a mold core 2 fixed in the groove 11, with a pattern for forming hydrogel microstructures machined on its bottom; a primary fluid channel 12 machined inside the upper mold base 1 and a secondary fluid channel 21 machined inside the mold core 2, the primary fluid channel 12 and the secondary fluid channel 21 being connected; a lower mold base 3 arranged parallel to the upper mold base 1, with a forming platform 4 on its top; an alignment guide mechanism including a pin 51 on the upper mold base 1 and a slot 52 on the lower mold base 3 that is adapted to the pin 51; and a locking member 6 located at the bottom of the lower mold base 3 for applying a locking force to the upper mold base 1 and the lower mold base 3 after mold closing.

[0040] Therefore, groove 11 is used for precise positioning and fixing of mold core 2, ensuring that the mold core will not shift during mold closing and pressure application. The negative microstructure pattern at the bottom of mold core 2 directly determines the positive microstructure shape after hydrogel molding. Primary fluid channel 12 and secondary fluid channel 21 may also be used for vacuuming to remove air bubbles during molding, or for injecting crosslinking agents in special processes. Their interconnected design ensures that fluid can smoothly reach the most critical molding surface of the mold core from the outside.

[0041] It should be noted that the mold core 2 and the groove 11 are fitted with an interference fit, which is achieved by utilizing its own elasticity to achieve a tight fixation. In addition, the mold core 2 is fixed in the groove 11 by an adhesive, so that it moves synchronously with the upper mold base 1 during the demolding process and does not detach.

[0042] In some embodiments, such as Figure 3As shown, the locking component 6 includes: a pad 61 located on the bottom surface of the lower mold base 3; two threaded columns 62, which are respectively vertically fixed to both sides of the upper surface of the pad 61; two arc-shaped pressure plates 63, which are respectively sleeved on the corresponding threaded columns 62; a nut 64, which is threadedly connected to the top of the threaded column 62; and grooves 14 that are adapted to the inner arc surface of the arc-shaped pressure plate 63 are machined on both sides of the upper mold base 1. Tightening the nut 64 can drive the arc-shaped pressure plate 63 to move downward and press it into the groove 14.

[0043] Specifically, two threaded columns 62 stand vertically on the pad 61, forming the basic frame of the locking mechanism. After the mold is closed, the slots 14 on both sides of the upper mold base 1 will be located exactly between the two threaded columns 62. The arc-shaped pressure plate 63 is fitted onto the threaded columns, and its inner arc surface matches the outer contour of the slot 14 of the upper mold base. Tightening the nut 64 will drive the arc-shaped pressure plate 63 to move downward along the threaded columns 62, thereby pressing the arc-shaped pressure plate 63 tightly into the slot 14.

[0044] Provides stable and uniform mold closing pressure for the upper mold base 1 and the lower mold base 3.

[0045] In some embodiments, such as Figure 1 As shown, the pad 61 is fixedly connected to the bottom surface of the lower mold base 3 by screws or locating pins;

[0046] Specifically, the fixing method between the pad 61 and the bottom surface of the lower mold base 3 can be selected according to the specific requirements, without any specific limitation.

[0047] In some embodiments, such as Figure 6 As shown, the forming platform 4 is installed on the upper surface of the lower mold base 3 via a threaded rod 41, and the threaded rod 41 engages with a threaded hole on the lower mold base 3.

[0048] Specifically, the upper surface of the molding platform 4 is machined with a "dam" structure. The height of the "dam" structure is lower than the height of the mold core 2. The interior of the "dam" structure is a flat, rigid surface used to hold the liquid hydrogel precursor solution. The hydrogel precursor solution has a certain viscosity and generally does not flow randomly, but can remain stably at the dripping position. The height of the molding platform 4 can be finely adjusted by rotating the threaded rod 41.

[0049] It should be noted that a "dam" structure is processed on the upper surface of the molding platform 4 so that after the mold is closed, the gap between the mold core 2 and the molding platform 4 is uniform, thereby obtaining a hydrogel film with a consistent thickness.

[0050] In some embodiments, such as Figure 2 As shown, the core 2 is made of a flexible material, namely polydimethylsiloxane;

[0051] Specifically, the core 2 can be made of materials such as polydimethylsiloxane or PDMS. Flexible materials such as PDMS have excellent hydrophobicity and elasticity, and the adhesion between them and the hydrogel is much less than that of traditional rigid metal or hard plastic molds.

[0052] During the demolding process, when the upper mold base 1 is lifted, the mold core 2 fixed thereon can undergo elastic deformation. Utilizing the deformation of the mold core 2, the contact surface with the hydrogel microstructure can be cleverly "peeled off" or "rolled away," thereby separating it from the formed hydrogel microstructure and preventing the fragile hydrogel microstructure from being torn or broken. This overcomes the problem in existing technologies using rigid molds where a purely vertical tensile force is required, leading to the hydrogel structure being torn or broken.

[0053] In some embodiments, such as Figure 4 As shown, the inlet end of the primary fluid channel 12 is connected to a fluid interface 13.

[0054] Specifically, before or during demolding, compressed air (or inert gas) or liquid release agent may be injected into the fluid channel through the fluid interface 13.

[0055] In some embodiments, such as Figure 5 As shown, the end of the pin 51 is tapered, and the entrance of the slot 52 is provided with a matching tapered guide surface;

[0056] Specifically, the tapered design of the end of pin 51 and the inlet of slot 52 provides a "self-guiding" effect. Even if there is a slight deviation in the initial position, it can be automatically corrected by sliding after the tapered surfaces make contact, ultimately guiding the upper and lower mold bases to precise alignment. This prevents misalignment, deformation, or damage to the microstructure pattern caused by misalignment.

[0057] In some embodiments, such as Figure 2 and Figure 3 As shown, the outlet end of the secondary fluid channel 21 extends to the microstructure pattern at the bottom of the mold core 2;

[0058] It should be noted that if gas is introduced: the gas escapes from the microstructure pattern at the bottom of the mold core, forming an extremely thin air cushion layer between the mold core and the hydrogel. This air cushion layer generates uniform pressure, which helps to "push open" the mold core and reduces the initial peeling force.

[0059] If a liquid release agent is introduced: the release agent will form a lubricating film between the mold core and the hydrogel, further reducing the interfacial adhesion and making the elastic demolding process of the flexible mold core smoother and more thorough.

[0060] The working principle of this application is illustrated below with a preferred embodiment:

[0061] The hydrogel prepolymer solution is dripped onto the molding platform 4, driving the upper mold base 1 to descend. The pin 51 is inserted into the slot 52, and the conical surface of the slot 52 guides the upper mold base 1 and the lower mold base 3 to be precisely aligned. Then, the arc-shaped pressure plate 63 is moved down in the threaded column 62 and the arc-shaped pressure plate 63 is inserted into the slot 14. Then, the nut 64 is used to fix the position of the arc-shaped pressure plate 63 on the threaded column 62, and then the locking part 6 fastens the upper mold base 1 and the lower mold base 3 after the mold is closed.

[0062] The pattern of mold core 2 is pressed into the hydrogel solution, and the hydrogel crosslinks and solidifies after a certain pressure and time.

[0063] Loosen the locking part 6 and introduce compressed air or release agent through the fluid interface 13. The gas or liquid reaches the surface of the mold core 2 through the primary fluid channel 12 and the secondary fluid channel 21. Since the mold core 2 is made of flexible material, the introduced compressed air or release agent can assist the mold core 2 to detach completely and without damage from the cured hydrogel microstructure through elastic deformation.

[0064] Finally, open the mold, remove the hydrogel product with microstructure, rotate the threaded rod 41 at the bottom of the molding platform 4 to separate it from the lower mold base 3, and then the molding platform 4 can be cleaned.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. An imprinting mold for forming hydrogel microstructures, characterized in that, include: The upper mold base (1) has a groove (11) machined on its bottom. The mold core (2) is fixed in the groove (11), and the bottom of the mold core (2) is processed with a pattern for forming hydrogel microstructures; The upper mold base (1) has a primary fluid channel (12) machined inside, and the mold core (2) has a secondary fluid channel (21) machined inside, and the primary fluid channel (12) and the secondary fluid channel (21) are connected. The lower mold base (3) is arranged parallel to the upper mold base (1), and a forming platform (4) is provided on the top of the lower mold base (3). The alignment guide mechanism includes a pin (51) disposed on the upper mold base (1) and a slot (52) disposed on the lower mold base (3) and adapted to the pin (51). The locking element (6) is located at the bottom of the lower mold base (3) and is used to apply a locking force to the upper mold base (1) and the lower mold base (3) after the mold is closed.

2. The imprinting mold for hydrogel microstructure molding according to claim 1, characterized in that, The locking element (6) includes: The pad (61) is located on the bottom surface of the lower mold base (3); Two threaded columns (62) are respectively vertically fixed to both sides of the upper surface of the pad (61); Two arc-shaped pressure plates (63) are respectively fitted onto the corresponding threaded columns (62); Nut (64) is threaded to the top of the threaded post (62); The upper mold base (1) has slots (14) on both sides that are adapted to the inner arc surface of the arc-shaped pressure plate (63); tightening the nut (64) can drive the arc-shaped pressure plate (63) to move downward and press into the slot (14).

3. The imprinting mold for hydrogel microstructure molding according to claim 2, characterized in that, The pad (61) is fixedly connected to the bottom surface of the lower mold base (3) by screws or positioning pins.

4. The imprinting mold for hydrogel microstructure molding according to claim 1, characterized in that, The forming platform (4) is installed on the upper surface of the lower mold base (3) by a threaded rod (41), and the threaded rod (41) is engaged with a threaded hole on the lower mold base (3).

5. The imprinting mold for hydrogel microstructure molding according to claim 1, characterized in that, The core (2) is made of a flexible material, namely polydimethylsiloxane.

6. The imprinting mold for hydrogel microstructure molding according to claim 1, characterized in that, The inlet end of the primary fluid channel (12) is connected to a fluid interface (13).

7. The imprinting mold for hydrogel microstructure molding according to claim 1, characterized in that, The end of the pin (51) is tapered, and the entrance of the slot (52) is provided with a tapered guide surface that matches it.

8. The imprinting mold for hydrogel microstructure molding according to claim 1, characterized in that, The outlet end of the secondary fluid channel (21) extends to the microstructure pattern at the bottom of the mold core (2).

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