Preparation method of a roller die and the roller die

Abstract

The present invention belongs to the technical field of mold preparation, and particularly relates to a preparation method of a roller mold and a roller mold. The preparation method of the roller mold comprises the following steps: sizing, preparing a fixed cylinder with a positioning cavity and a master mold with a forming cavity, wherein the cavity wall of the forming cavity is provided with microstructures, sleeving the master mold inside the fixed cylinder and positioning it in the positioning cavity; pouring, pouring a fluid-shaped forming material into the forming cavity, and forming the forming material into a predetermined shape in the forming cavity; curing, curing the forming material so that the forming material replicates the microstructures; carbonizing, separating the cured forming material from the master mold and heating the forming material so that the forming material is carbonized to form a roller mold. Through the four steps of sizing, pouring, curing and carbonizing, the forming material can accurately replicate the microstructures on the master mold, improve the preparation precision of the roller mold, and has low preparation cost and high efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of mold preparation, and particularly relates to a preparation method of a roller mold and a roller mold. Background Art

[0002] Micro-optical elements such as microlens arrays, Fresnel lenses, and metasurfaces play an important role in modern optics and optoelectronic technologies, and are widely used in many fields such as consumer electronics, medical imaging, optical communication, and energy harvesting.

[0003] Manufacturing microstructures on the surface of a roller mold and using the roller mold for hot embossing of optical glass is a new processing method for mass-producing micro-optical elements. In the roll-to-plate hot embossing technology, the roller mold not only involves the forming of the shape, but also involves multiple aspects such as heating, pressing, process control, and performance improvement. Its preparation and application directly affect the quality, production efficiency, and material properties of the final product. Therefore, in practical applications, manufacturing high-quality roller molds is a key factor to ensure successful forming.

[0004] Traditionally, the preparation of an integrated roller mold is mainly through single-point diamond turning technology. However, the requirements of this processing method are relatively high, which greatly increases the processing cost, and the production efficiency is relatively low. The accuracy of the surface structure is limited by the accuracy of the machine tool and the algorithm, and it cannot meet the needs of mass-producing, low-cost, and high-precision roller mold manufacturing. Summary of the Invention

[0005] The purpose of the embodiments of the present application is to provide a preparation method of a roller mold, aiming to solve the problem of how to improve the preparation efficiency of the roller mold and reduce the preparation cost.

[0006] To achieve the above purpose, the technical solution adopted in the present application is as follows:

[0007] In a first aspect, a preparation method of a roller mold is provided, which includes the following steps:

[0008] Sizing: Prepare a fixed cylinder with a positioning cavity and a master mold with a forming cavity. The cavity wall of the forming cavity is provided with microstructures. The master mold is sleeved inside the fixed cylinder and positioned in the positioning cavity.

[0009] Pouring: Pour a fluid-shaped forming material into the forming cavity, and the forming material forms a predetermined shape in the forming cavity.

[0010] Curing: Cure the forming material so that the forming material replicates the microstructures.

[0011] Carbonization: Separate the cured forming material from the master mold and heat the forming material so that the forming material is carbonized to form a roller mold.

[0012] In some embodiments, the shaping step includes:

[0013] S11: Prepare a flexible sheet;

[0014] S12: Process the microstructures on one side surface of the flexible sheet;

[0015] S13: Connect the opposite ends of the flexible sheet to make the flexible sheet curl and form the master mold.

[0016] In some embodiments, the microstructures are processed on the flexible sheet by femtosecond laser technology or lithography technology.

[0017] In some embodiments, the opposite ends of the flexible sheet are spliced or partially overlapped and connected.

[0018] In some embodiments, the curing step includes:

[0019] S31: Place the fixing cylinder and the molding material in a vacuum environment and maintain for a first predetermined duration;

[0020] S32: Then place the fixing cylinder and the molding material in a dry environment and heat to a first predetermined temperature, and maintain for a second predetermined duration to cure the molding material.

[0021] In some embodiments, the range of the first predetermined duration is 72h - 100h, the range of the second predetermined duration is 8h - 10h, and the range of the first predetermined temperature is 100 °C - 105 °C.

[0022] In some embodiments, the carbonization step includes:

[0023] S41: Place the cured molding material in a vacuum environment;

[0024] S42: Heat the molding material to a second predetermined temperature at a first predetermined heating rate;

[0025] S43: Heat the molding material from the second predetermined temperature to a third predetermined temperature at a second predetermined heating rate, where the second predetermined heating rate is greater than the first predetermined heating rate, and the third predetermined temperature is greater than the second predetermined temperature;

[0026] S44: Keep the molding material at the third predetermined temperature for a third predetermined duration;

[0027] S45: Naturally cool the molding material to obtain the roller mold.

[0028] In some embodiments, the first predetermined heating rate is 0.5 °C / min, the second predetermined heating rate is 1 °C / min, the second predetermined temperature is 600 °C, the third predetermined temperature is 1000 °C, and the third predetermined duration is 10 h.

[0029] In some embodiments, the molding material includes 89.8% furan resin, 0.2% p-toluenesulfonic acid monohydrate, and 10% ethanol by mass fraction.

[0030] In a second aspect, a roller die is provided, which is prepared by the method for preparing a cylindrical die described above.

[0031] The beneficial effects of the present application are as follows: Through the four steps of sizing, casting, curing, and carbonization, the transformation of the molding material from a fluid plastic state to a solid state is ensured, guaranteeing the structural stability and high-temperature resistance of the roller die. The molding material in the plastic state can accurately replicate the microstructures on the master die to achieve the replication and transfer of the microstructures, improving the preparation accuracy of the roller die, and having low preparation cost and high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or exemplary technical descriptions. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0033] Figure 1 is a flowchart of the method for preparing a roller die provided by an embodiment of the present application;

[0034] Figure 2 is a schematic diagram of the casting step in the method for preparing a roller die provided by another embodiment of the present application;

[0035] Figure 3 is an assembly schematic diagram of a fixed cylinder and a sizing member provided by another embodiment of the present application;

[0036] Figure 4 is a three-dimensional structural schematic diagram of a fixed cylinder and a master die provided by another embodiment of the present application;

[0037] Figure 5 is a three-dimensional structural schematic diagram of a roller die provided by another embodiment of the present application;

[0038] Figure 6 is Figure 5 a partial enlarged view of part A of

[0039] Among them, the reference numerals in the drawings are as follows:

[0040] 101. Fixed cylinder; 102. Female mold; 103. Molding material; 104. Shaping member; 1041. Shaping tube; 1042. Shaping column; 105. Positioning cavity; 200. Roller die; 201. Micro-protrusion; 1011. Half set; 1021. Half piece; 1022. Molding cavity; 1012. Avoidance groove. Detailed implementation manners

[0041] In order to make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to 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.

[0042] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it can 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 can be directly or indirectly connected to the other component. The orientation or positional relationship indicated by words such as "upper", "lower", "left", and "right" is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of description, rather than indicating or implying 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 of the present application. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances. The terms "first" and "second" are only used for the purpose of convenient description and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. The meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0043] Please refer to Figures 1 to 3 , the embodiment of the present application provides a preparation method for a roller die, which is used to prepare the roller die 200. The roller die 200 can perform hot pressing on optical glass to prepare an optical element with a micro-structure.

[0044] Please refer to Figures 2 to 4 , the preparation method of the roller die includes the following steps:

[0045] S1: Shaping. Prepare a fixing cylinder 101 with a positioning cavity 105 and a female mold 102 with a forming cavity 1022. The positioning cavity 105 has an opening which is arranged upward. The inner wall of the forming cavity 1022 is provided with microstructures. The female mold 102 is sleeved and positioned within the fixing cylinder 101, such that the outer surface of the female mold 102 is in close contact with the cavity wall of the positioning cavity 105, and the female mold 102 is fixed and supported. It can be understood that an adhesive layer can be provided on the inner wall of the fixing cylinder 101, thereby adhesively fixing the female mold 102 to the cavity wall of the positioning cavity 105; the cross-sectional shape of the positioning cavity 105 is circular, and the cross-sectional shape of the female mold 102 is also circular. At the same cross-sectional position, the center of the cross-section of the positioning cavity 105 coincides with the center of the cross-section of the female mold 102.

[0046] S2: Pouring. Pour the formable material 103 in a fluid state and a plastic state into the forming cavity 1022 of the female mold 102, and form the formable material 103 into a predetermined shape within the forming cavity 1022. In this embodiment, the formable material 103 is formed into a cylinder within the forming cavity 1022; it can be understood that the formable material 103 is slowly injected into the forming cavity 1022, such that the formable material 103 fills the forming cavity 1022 and submerges the uppermost microstructures of the forming cavity 1022. Finally, the formable material 103 is in a cylindrical shape within the forming cavity 1022.

[0047] S3: Curing. Cure the formable material 103 within the forming cavity 1022, such that the formable material 103 replicates the microstructures; it can be understood that the formable material 103 in a fluid state and having viscoelasticity has strong plasticity and can fully fill the microstructures on the female mold 102, such that the cured formable material 103 can accurately replicate the microstructures on the female mold 102, has a high replication accuracy, realizes the transfer of high-precision microstructures, and has high efficiency.

[0048] S4: Carbonization. Separate the formable material 103 from the female mold 102, and heat the formable material 103 with replicated microstructures, such that the formable material 103 is carbonized to form a roller die 200. It can be understood that the carbonized roller die 200 has a certain hardness and strength, and also has the characteristic of being heat-resistant, thereby enabling subsequent hot pressing forming.

[0049] Please refer to Figures 1 to 3 , the method for preparing a roller die provided by the embodiment of the present application, through four steps of shaping, pouring, curing, and carbonization, ensures the transformation of the formable material 103 from a fluid state to a solid state, guarantees the structural stability and heat-resistant performance of the roller die 200. The formable material 103 can accurately replicate the microstructures on the female mold 102 to realize the replication and transfer of the microstructures, improves the preparation precision of the roller die 200, and has low preparation cost and high efficiency.

[0050] Optionally, the microstructure includes microstructures with a size in the micrometer range and / or microstructures with a size in the nanometer range. The obtained roller die is cleaned and polished to improve its surface quality. The shape of the microstructure can be cavities, protrusions or grooves, which are not limited here and can be selected according to the actual situation.

[0051] Optionally, the material of the fixed cylinder 101 can be a metal material, such as stainless steel. Stainless steel is a type of alloy steel with high corrosion resistance, and its main components are iron, chromium and carbon. Stainless steel can form a dense chromium oxide protective film in air or water, thus effectively preventing rust and corrosion, enabling the fixed cylinder 101 to be reused repeatedly and reducing the preparation cost of the roller die 200.

[0052] Optionally, a shaping member 104 is provided inside the fixed cylinder 101. The cross-sectional shape of the shaping member 104 is circular, and the center of the circle coincides with the center of the cross-section of the positioning cavity. The molding material 103 is poured between the side surface of the shaping member 104 and the inner surface of the master mold 102, thereby finally obtaining the roller die 200 with a hollow structure.

[0053] Please refer to Figures 1 to 3 , in some embodiments, the molding material 103 includes furan resin with a mass fraction of 89.8%, p-toluenesulfonic acid monohydrate with a mass fraction of 0.2%, and ethanol with a mass fraction of 10%.

[0054] Optionally, the molding material 103 has good forming performance and carbonization effect. After carbonization, the furan resin can form a high-strength carbonized structure, ensuring the stability and wear resistance of the roller die 200 in a high-temperature environment.

[0055] Toluenesulfonic acid, as a catalyst, can accelerate the curing process of the molding material 103, and the addition of ethanol helps to improve the fluidity of the material, ensuring uniform and sufficient filling of the microstructure during the pouring process.

[0056] Please refer to Figures 1 to 3 , in some embodiments, the shaping step includes:

[0057] S11: Prepare a flexible sheet;

[0058] S12: Process microstructures on one side surface of the flexible sheet;

[0059] S13: Connect the opposite ends of the flexible sheet to make the flexible sheet curl and form the master mold 102.

[0060] Optionally, the flexible sheet can be a PDMS (Polydimethylsiloxane) sheet, which is a silicone polymer material with flexible properties and is widely used in fields such as optics, microelectronics, biomedicine, and microelectromechanical systems. The PDMS sheet has a high elastic modulus and can maintain its structural integrity under large deformations, enabling it to be curled into a circular sleeve shape.

[0061] Optionally, microstructures are processed on one side surface of the PDMS sheet, and the opposite ends of the PDMS sheet are docked, so that the PDMS sheet is curled into a sleeve shape to form the female mold 102, and the microstructures are located on its inner surface.

[0062] Please refer to Figures 1 to 3 , in some embodiments, microstructures are processed on the flexible sheet by femtosecond laser technology.

[0063] Optionally, microstructures can be processed on the PDMS sheet by femtosecond laser technology. Using the high precision and extremely short pulses of femtosecond laser to engrave microstructures with micron to nanometer scales on the surface of the PDMS sheet, complex micro-nano patterns can be processed. The action time of femtosecond laser technology is short and the energy is concentrated, so a large amount of energy can be deposited instantaneously in a very small area, reducing the thermal effect of the material. Femtosecond laser processing is a non-contact process and does not apply mechanical stress to the material surface, avoiding stress concentration on the flexible sheet.

[0064] In some embodiments, microstructures are processed on the flexible sheet by lithography technology.

[0065] Optionally, lithography technology can generate high-precision microstructures on the PDMS sheet, and periodic patterns and complex geometries can be prepared. Femtosecond laser and lithography technology can process complex microstructures in micron size and / or nanometer size, ensuring the precision and consistency of the microstructures.

[0066] Please refer to Figures 1 to 4 , in some embodiments, the opposite ends of the flexible sheet are spliced, and glue is coated on the end faces of the two spliced ends of the flexible sheet, so that the two ends of the flexible sheet are firmly connected by the glue and the flexible sheet is curled into the female mold 102. A first adhesive layer can also be provided at the splicing position. The two ends of the first adhesive layer are respectively adhesively connected to the two ends of the flexible sheet, so that the two ends of the flexible sheet are spliced in a face-to-face form, avoiding protrusions at the docking position of the two ends of the flexible sheet. The first adhesive layer is located between the flexible sheet and the cavity wall of the positioning cavity 105. A first avoidance groove 1012 can also be opened on the cavity wall of the positioning cavity 105 corresponding to the first adhesive layer, and a part of the first adhesive layer is located in the first avoidance groove 1012, so as to reduce the influence of the thickness of the first adhesive layer on the curling shape of the female mold.

[0067] Please refer to Figures 1 to 3, in some embodiments, opposite end portions of the flexible sheet are overlapped and connected.

[0068] Optionally, a second adhesive layer may be provided at the overlap of the two ends of the flexible sheet, and both side surfaces of the second adhesive layer are adhesively bonded to the two ends of the flexible sheet respectively.

[0069] It can be understood that during the subsequent process of hot pressing the sheet-shaped optical glass by the roller die, the optical glass can avoid the positions of the roller die corresponding to the first adhesive layer or the second adhesive layer, so as to prevent hot pressing of the optical glass at these positions. That is, the rotation angle of the roller die during the rolling process is less than 360 degrees, and can be 300 degrees, 320 degrees or 330 degrees, thereby improving the hot pressing accuracy of the optical glass.

[0070] Please refer to Figure 4 , it can be understood that the fixing cylinder 101 includes two half sleeves 1011, and two sides of one half sleeve 1011 are respectively butted against two sides of the other half sleeve 1011, that is, the two half sleeves 1011 are butted along the radial direction of the master mold to form a positioning cavity 105. The two half sleeves 1011 are detachably connected, and the detachable connection of the two half sleeves 1011 can be realized by a hoop or a connecting member. By separating the two half sleeves 1011, the flexible sheet and the molding material 103 can be separated from the fixing cylinder 101 together, and then the two ends of the flexible sheet are manually disassembled, so as to separate the flexible sheet from the molding material 103. The flexible sheet can be reused, reducing the preparation cost of the roller die 200, and enabling mass and large-scale preparation of the roller die 200.

[0071] Optionally, the flexible sheet includes two half sheets 1021, and the two half sheets 1021 are respectively located in the two half sleeves 1011 and are bent to fit the inner wall of the half sleeve 1011. By butting the two half sleeves 1011, the butting of the two half sheets 1021 can be realized, improving the butting accuracy and efficiency of the two half sheets 1021. Moreover, the flexible sheet can be bent to fit in the two half sleeves 1011. By positioning the bending shape of the half sheet 1021 through the inner wall of the half sleeve 1011, the cross-sectional shape of the bent half sheet 1021 is a semi-circle, improving the shape accuracy of the final forming cavity 1022. Two avoidance grooves 1012 are provided, and the two avoidance grooves 1012 are respectively located at the two butting positions of the two half sheets 1021, and a first adhesive layer is provided in each avoidance groove 1012.

[0072] Please refer to Figures 1 to 3 , in some embodiments, the curing step includes:

[0073] S31: Place the fixing cylinder 101 and the molding material 103 in a vacuum environment and maintain for a first predetermined time; the vacuum degree of the vacuum environment can be 0.001 Pa;

[0074] S32: Then, place the fixing cylinder 101 and the molding material 103 in a dry environment and heat them to a first predetermined temperature, and maintain for a second predetermined duration to cure the molding material 103.

[0075] Optionally, place the fixing cylinder 101, the female mold 102, and the molding material 103 in a vacuum chamber, and cure the molding material 103 in the vacuum environment of the vacuum chamber, so as to effectively remove air and bubbles in the molding material 103, ensure the density and uniformity of the roller die 200, and the reduction of bubbles can also improve the pressure resistance and service life of the roller die 200.

[0076] Then, place the fixing cylinder 101 in a convection drying oven. By controlling the heating temperature and maintaining for a second predetermined duration, the molding material 103 can be completely cured and its internal stress can be reduced, avoiding deformation or shrinkage of the molding material 103 during subsequent processing.

[0077] Please refer to Figure 3 , the sizing member 104 includes a tubular sizing tube 1041 and a sizing post 1042 that can be inserted into the sizing tube 1041. The material of the sizing tube 1041 can be a high-temperature resistant elastic material, such as high-temperature resistant silicone, and the material of the sizing post 1042 can be stainless steel. The cross-sectional shapes of both the sizing tube 1041 and the sizing post 1042 are circular. In the pouring step, first insert one end of the sizing tube 1041 into and position it in the molding cavity 1022, seal the inserted end of the sizing tube 1041, then insert the sizing post 1042 into the sizing tube 1041 and have an interference fit with the sizing tube 1041, and then pour the fluid and plastic molding material 103 into the molding cavity 1022.

[0078] In the early stage of step S32, the molding material 103 will gradually cure but not completely cure. After the molding material 103 is initially formed, that is, in the later stage of step S32, withdraw the sizing post 1042 from the sizing tube 1041, and fill a certain pressure of gas or liquid into the sizing tube 1041 to cause the sizing tube 1041 to expand radially, so that the sizing tube 1041 slightly extrudes the molding material 103 outward, so that there is a certain lateral pressure between the molding material 103 and the female mold 102, ensuring that the microstructures on the molding material 103 can have the required replication accuracy, and preventing the molding material 103 from shrinking too fast due to curing, which affects the replication accuracy of the microstructures.

[0079] Of course, the sizing member 104 can also be an expansion tube, and the expansion tube can expand radially along it.

[0080] Please refer to Figures 1 to 3, in some embodiments, the range of the first predetermined duration is 72h to 100h, the range of the second predetermined duration is 8h to 10h, and the range of the first predetermined temperature is 100 degrees Celsius to 105 degrees Celsius.

[0081] Optionally, the first predetermined duration can be 72h, 80h, 85h, 95h, 99h or 100h, and the second predetermined duration can be 8h, 8.5h, 8.8h, 9h, 9.9h or 10h. There is no limitation here and it can be selected according to the actual situation.

[0082] The first predetermined temperature can be 100 degrees Celsius, 101 degrees Celsius, 102.3 degrees Celsius or 105 degrees Celsius. There is no limitation here and it can be selected according to the actual situation.

[0083] Please refer to Figures 1 to 3 , in some embodiments, the carbonization step includes:

[0084] S41: Place the cured molding material 103 in a vacuum environment or an inert gas environment; the vacuum degree of the vacuum environment can be 0.001 Pa, and the inert gas can be nitrogen or argon.

[0085] S42: Heat the molding material 103 to the second predetermined temperature at the first predetermined heating rate;

[0086] S43: Heat the molding material 103 from the second predetermined temperature to the third predetermined temperature at the second predetermined heating rate, where the second predetermined heating rate is greater than the first predetermined heating rate, and the third predetermined temperature is greater than the second predetermined temperature;

[0087] S44: Keep the molding material 103 at the third predetermined temperature for the third predetermined duration to fully carbonize the molding material 103;

[0088] S45: Naturally cool the molding material 103 to obtain the roller die 200. The molding material 103 can be naturally cooled for 24 hours to cool the molding material 103 to room temperature.

[0089] Optionally, through the first predetermined heating rate, the molding material 103 can be effectively heated slowly to the second predetermined temperature, which can control the shrinkage and internal stress distribution of the molding material 103, avoid cracks or internal stress concentration in the molding material 103 and the microstructure during the rapid heating process, and help to fully carbonize the molding material 103, ultimately improving the reliability of the roller die 200 and the dimensional accuracy of the microstructure. And through the second predetermined heating rate, the heating rate of the molding material 103 can be increased, the carbonization efficiency can be improved, and the third predetermined temperature can strengthen the carbonization of the molding material 103.

[0090] Please refer to Figures 1 to 3, in some embodiments, the first predetermined heating rate may be 0.5 °C / min; the second predetermined heating rate may be 1 °C / min; the second predetermined temperature may be 600 °C, the third predetermined temperature may be 1000 °C, and the third predetermined duration may be 10 h.

[0091] Optionally, by sequentially adopting heating rates of 0.5 °C / min and 1 °C / min, precise control of the temperature rise process of the molding material 103 is achieved, and the carbonization process is controlled. Since the thermal decomposition of the furan precursor is mainly concentrated around 600 °C, the heating rate within 600 °C is set to slow heating at 0.5 °C / min, so that the molding material 103 is slowly heated to 600 degrees Celsius, and the molding material 103 undergoes sufficient carbonization. Then, through rapid heating at 1 °C / min, the molding material 103 is heated from 600 °C to 1000 °C, achieving rapid temperature rise of the molding material 103, strengthening the carbonization effect, and accelerating the carbonization efficiency.

[0092] Optionally, the slow heating at the first predetermined heating rate can make the molding material 103 heat evenly. It can not only make the molding material 103 undergo sufficient thermal decomposition to ensure the uniformity of material thermal decomposition, but also reduce the occurrence of warping, internal cracks, and voids in the glassy carbon, improve the carbonization effect, avoid local overheating or stress concentration, thereby ensuring the quality and structural strength of the surface microstructure of the roller die 200.

[0093] It can also be understood that the furan precursor has strong plasticity in the viscoelastic state. It can precisely replicate the microstructure on the master mold 102, ensuring the accuracy of the microstructure on the roller die 200. After carbonization, the furan precursor forms glassy carbon with high temperature resistance and high hardness, obtaining a roller die 200 with high dimensional accuracy integrated with glassy carbon, that is, the microstructure and the matrix of the roller die 200 are integrally formed, which can ensure the overall connection strength and structural strength.

[0094] Optionally, subsequently, the roller die 200 is used to transfer the microstructure to the optical glass. On the premise of ensuring the transfer accuracy, it solves the pain points of high cost, low efficiency, and limited accuracy of the traditional single-point diamond turning technology. Moreover, the glassy carbon roller die 200 has low adhesion to the glass, which can reduce the defect of adhesive failure between the optical glass and the roller die 200 during the hot embossing process, and improve the product quality of the hot embossing.

[0095] Please refer to Figures 5 to 6 , the present invention also proposes a roller die 200, which is prepared by the above preparation method of the roller die. Since this roller die 200 adopts all the technical solutions of all the above embodiments, it also has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be elaborated herein one by one.

[0096] Please refer to Figure 6 In this embodiment, the side surface of the roller die 200 has a microstructure, which is a micro-protrusion 201 protruding from the side surface of the roller die 200. The micro-protrusion 201 is strip-shaped and arranged along the length direction of the roller die 200. A plurality of micro-protrusions 201 are arranged at equal intervals along the circumferential direction of the roller die 200. In other embodiments, the microstructure may also be in the shape of a columnar body, which is not limited herein and can be selected according to actual situations.

[0097] 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, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A method for preparing a roller mold, characterized in that: The steps include: Finalizing the shape, preparing a fixed cylinder with a positioning cavity and a master mold with a molding cavity, wherein the cavity wall of the molding cavity is provided with a microstructure, and the master mold is sleeved inside the fixed cylinder and positioned in the positioning cavity; Pouring, pouring a fluid molding material into the molding cavity, wherein the molding material is molded into a predetermined shape in the molding cavity; Curing, curing the molding material so that the molding material replicates the microstructure; The curing step comprises: S31: placing the fixing cylinder and the molding material in a vacuum environment and maintaining the vacuum environment for a first predetermined time; S32: placing the fixing tube and the molding material in a dry environment and heating them to a first predetermined temperature, and maintaining the temperature for a second predetermined time to solidify the molding material; A shaping piece is arranged in the fixed tube, and the shaping piece includes a shaping tube in a tubular shape and a shaping column inserted into the shaping tube, and the shaping tube is made of a high-temperature resistant elastic material; in the early stage of step S32, the molding material will gradually solidify but not completely solidify, and after the molding material is initially formed, in the later stage of step S32, the shaping column is withdrawn from the shaping tube, and a gas or liquid with a certain pressure is filled into the shaping tube to make the shaping tube expand radially, so that the shaping tube squeezes the molding material outward, so that there is a certain lateral pressure between the molding material and the master mold, and it is ensured that the microstructure on the molding material can have the required replication accuracy; Carbonization, separating the solidified molding material from the master mold, and heating the molding material to carbonize the molding material to form a roller mold.

2. The method for preparing a roller mold according to claim 1, characterized in that: The shaping step comprises: S11: preparing a flexible sheet; S12: processing the microstructure on one side surface of the flexible sheet; S13: connecting two opposite ends of the flexible sheet to curl the flexible sheet and form the master mold.

3. The method for preparing a roller mold according to claim 2, characterized in that: The microstructure is processed on the flexible sheet by using femtosecond laser technology or photolithography technology.

4. The method for preparing a roller mold according to claim 2, characterized in that: The two opposite ends of the flexible sheet are spliced ​​or partially overlapped and connected.

5. The method for preparing a roller mold according to any one of claims 1 to 4, characterized in that: The first predetermined time ranges from 72 hours to 100 hours, the second predetermined time ranges from 8 hours to 10 hours, and the first predetermined temperature ranges from 100 degrees Celsius to 105 degrees Celsius.

6. The method for preparing a roller mold according to any one of claims 1 to 4, characterized in that: The carbonization step comprises: S41: placing the solidified molding material in a vacuum environment; S42: heating the molding material to a second predetermined temperature at a first predetermined heating rate; S43: heating the molding material from the second predetermined temperature to a third predetermined temperature at a second predetermined heating rate, wherein the second predetermined heating rate is greater than the first predetermined heating rate, and the third predetermined temperature is greater than the second predetermined temperature; S44: keeping the molding material at the third predetermined temperature for a third predetermined time; S45: naturally cooling the molding material to obtain the roller mold.

7. The method for preparing a roller mold according to claim 6, characterized in that: The first predetermined heating rate is 0.5°C / min, the second predetermined heating rate is 1°C / min, the second predetermined temperature is 600°C, the third predetermined temperature is 1000°C, and the third predetermined time is 10h.

8. The method for preparing a roller mold according to any one of claims 1 to 4, characterized in that: The molding material includes 89.8% by mass of furan resin, 0.2% by mass of p-toluenesulfonic acid monohydrate, and 10% by mass of ethanol.

9. A roller mold, characterized in that: The roller mold is prepared by the preparation method of any one of claims 1 to 8.

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