Automatic production system and process for polymer solid microneedles

Abstract

The invention provides an automatic production system and process for polymer solid microneedles, and relates to the technical field of medical instrument manufacturing, the production system comprises an automatic conveying unit, a raw material pretreatment module, a dot-matrix type automatic quantitative feeding module, a pressure forming module, a cooling shaping module, a demolding sorting module and a branch line module; the continuity among the production steps is high, and the large-batch requirement is met through continuous production; the dot-matrix type automatic quantitative charging module is also provided with an independent temperature control charging unit which can accurately control the temperature to adjust the melt viscosity of the polymer so as to adapt to the processing characteristics of different raw materials and improve the charging precision and uniformity; the demolding and sorting module is used for detecting and sorting in real time and dynamically feeding back; the branch line module performs qualified product sterilization and defective product recovery, so that cyclic utilization and resource recovery are realized; according to the invention, the technical problems of isolated working procedures, low efficiency, poor material adaptability, low feeding precision and uniformity, lagging quality monitoring and low resource utilization rate in the existing production are solved.

Description

Technical Field

[0001] This invention relates to the field of medical device manufacturing technology, specifically to an automated production system and process for polymer solid microneedles. Background Technology

[0002] Clinically, using microneedles to create microchannels for drug delivery is an effective way to improve the efficiency of drug therapy at the skin interface. However, most microneedles are made of metal, posing significant risks to patient compliance and safety. Polymer solid microneedles, as a cutting-edge transdermal drug delivery and skin pretreatment tool, have shown great application potential in drug delivery, vaccine immunization, medical aesthetics, and diagnostic monitoring due to their advantages such as being painless, minimally invasive, biodegradable, and easy to load with active ingredients. Their diverse mechanical properties, degradation rates, and biocompatibility make them suitable for different clinical scenarios, enabling iterative upgrades to existing clinical products.

[0003] However, current manufacturing technologies for polymer solid microneedles, especially industrial-scale production processes, face several challenges: First, fragmented production models result in low efficiency. Laboratory and small-scale production often relies on discontinuous processes such as centrifugal filling, vacuum molding, and micro-injection molding. These methods involve isolated steps, requiring manual intervention or material transfer between each stage (e.g., feeding, molding, demolding), hindering continuous, automated production lines. This leads to long production cycles, limited capacity, and high labor costs, failing to meet large-scale market demands. Second, rigid process parameters result in poor material adaptability. Polymers such as polycaprolactone, polylactic acid, and polymethyl methacrylate exhibit vastly different melting temperatures, viscosity characteristics, and thermodynamic behaviors. For example, polycaprolactone requires a lower processing temperature (approximately 60-80°C), while polylactic acid and polymethyl methacrylate require higher temperatures (approximately 150-200°C). Existing equipment typically employs fixed or empirically adjusted process parameters, making it difficult to flexibly and accurately adapt to the optimal processing windows (e.g., temperature, pressure, cooling rate) for different materials on a single platform. This leads to large fluctuations in yield when switching materials, making it difficult to guarantee product consistency; third, controlling the accuracy and uniformity of material feeding is difficult: the microneedle cavity size is tiny (usually tens to hundreds of micrometers in diameter), requiring extremely high precision in the metering and uniform distribution of the filling material. Traditional methods such as drop coating and scraping are prone to producing cavities, uneven filling, or tip defects, affecting the mechanical strength and functional reliability of the microneedles. While high-precision hot melt 3D printing technology has seen some application, its printing accuracy remains unsatisfactory, and it lacks effective temperature control and multi-component simultaneous co-injection capabilities for high-viscosity polymer melts, limiting the controllable preparation of functional composite microneedles (such as single-layer or multi-layer structures, drug-loaded microneedles). Fourth, quality monitoring is lagging, lacking real-time feedback. Current processes rely heavily on offline sampling inspections after production, failing to achieve real-time online detection and sorting during production. This results in defective products not being promptly removed, potentially flowing into subsequent stages and causing waste, and also fails to provide data support for timely adjustments to process parameters, hindering the optimization of production stability. Fifth, resource utilization is low, lacking a green closed loop. Defective products and scraps generated during production are typically treated as waste, failing to achieve effective recycling and reuse. This not only increases raw material costs and environmental burden but also fails to reflect the concept of sustainable manufacturing. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defects in the prior art, thereby providing an automated production system and process for polymer solid microneedles.

[0005] An automated production system for polymer solid microneedles includes: an automated conveying unit; the production system further includes a raw material pretreatment module, a dot-matrix automatic quantitative feeding module, a pressure molding module, a cooling and shaping module, and a demolding and sorting module connected sequentially along the automated conveying unit; the raw material pretreatment module melts the raw materials to be processed and conveys them to the dot-matrix automatic quantitative feeding module; the dot-matrix automatic quantitative feeding module fills the molten polymer after molten treatment into a mold and conveys it to the pressure molding module; the pressure molding module pressurizes the molten polymer filled into the mold and conveys it to the cooling and shaping module; the cooling and shaping module cools and shapes the mold after pressure molding and conveys it to the demolding and sorting module; the demolding and sorting module demolds and sorts the molds after cooling and shaping; the dot-matrix automatic quantitative feeding module integrates a temperature-controlled feeding unit; the production system also includes a branch module connected to the demolding and sorting module, which is used to irradiate and sterilize qualified products and recycle defective products after sorting by the demolding and sorting module.

[0006] Furthermore, the branch module includes a qualified product irradiation sterilization module and a defective product recycling module; the qualified product irradiation sterilization module is connected to the demolding and sorting module, and is used to irradiate and sterilize the qualified products sorted by the demolding and sorting module; the defective product recycling module is connected to both the demolding and sorting module and the raw material pretreatment module, and is used to transport the unqualified products sorted by the demolding and sorting module to the raw material pretreatment module.

[0007] Furthermore, the branch module also includes a qualified product packaging module, which is connected to the qualified product irradiation sterilization module. The qualified product packaging module is used to automatically package the qualified products after irradiation sterilization.

[0008] Furthermore, the production system also includes a central control unit, which is connected to the raw material pretreatment module, the dot matrix automatic quantitative feeding module, the pressure molding module, the cooling and shaping module, the demolding and sorting module, the qualified product irradiation sterilization module, the defective product recycling module, and the qualified product packaging module.

[0009] Furthermore, the defective product recycling module includes a crushing unit, a melt extrusion unit, and a granulation unit connected in sequence. The crushing unit is connected to the demolding and sorting module, and the granulation unit is connected to the raw material pretreatment module. The crushing unit is used to crush the defective products sorted by the demolding and sorting module, the melt extrusion unit is used to melt extrude the crushed defective products, and the granulation unit is used to granulate the melt extruded defective products and transport them to the raw material pretreatment module.

[0010] Furthermore, the raw material pretreatment module includes an automatic feeding unit, a vacuum drying unit, and a precision melting and plasticizing unit connected in sequence. The automatic feeding unit is connected to the granulation unit, and the precision melting and plasticizing unit is connected to the dot matrix automatic quantitative feeding module. The automatic feeding unit is used to weigh and mix the new raw material and the recycled raw material processed by the granulation unit according to the ratio and transport them to the vacuum drying unit. The vacuum drying unit is used to remove moisture from the mixed raw material and transport it to the precision melting and plasticizing unit. The precision melting and plasticizing unit is used to melt the moisture-removed raw material and transport it to the dot matrix automatic quantitative feeding module.

[0011] Furthermore, the production system also includes a machine vision inspection system, which is integrated into the demolding and sorting module.

[0012] Furthermore, the temperature-controlled feeding unit is a multi-channel heating and sampling device, which also integrates a visual positioning system.

[0013] Furthermore, the processing raw materials include polycaprolactone, polylactic acid, and polymethyl methacrylate.

[0014] The present invention also includes an automated manufacturing process for polymer solid microneedles, which is based on an automated manufacturing system for polymer solid microneedles as described in any of the preceding claims, and the process includes the following steps: Step S1: The raw materials to be processed are melted in the raw material pretreatment module and then conveyed to the dot matrix automatic quantitative feeding module; Step S2: The molten polymer after melting treatment is filled into the mold and conveyed to the pressure molding module through the dot matrix automatic quantitative feeding module; Step S3: The molten polymer filled into the mold is pressurized and molded by the pressure molding module and then conveyed to the cooling and shaping module; Step S4: The mold formed under pressure is cooled and shaped by the cooling and shaping module and then conveyed to the demolding and sorting module. Step S5: Demolding and sorting the cooled and shaped molds using the demolding and sorting module; Step S6: The qualified products sorted by the demolding and sorting module are irradiated, sterilized, packaged, and the defective products are recycled through the branch line module.

[0015] The technical solution of this invention has the following advantages: The technical solution provided by this invention integrates an automated conveying unit, a raw material pretreatment module, a dot-matrix automatic quantitative feeding module, a pressure molding module, a cooling and shaping module, and a demolding and sorting module in series. This realizes a process from raw material processing to production and manufacturing, with strong continuity between each step, forming a continuous production mode to meet the needs of large-scale production. The dot-matrix automatic quantitative feeding module also has an independent temperature-controlled feeding unit, which can accurately control the temperature to adjust the melt viscosity of the polymer to adapt to the processing characteristics of different raw materials. Moreover, it achieves the controllable construction of single-layer or multi-layer multifunctional composite solid microneedles within a single microneedle cavity, improving the accuracy and uniformity of feeding. By setting up a demolding and sorting module for synchronous real-time detection and sorting, dynamic feedback can be provided. The branch module irradiates and sterilizes qualified products after being sorted by the demolding and sorting module, or recycles and reprocesses defective products, realizing the recycling of resources. Attached Figure Description

[0016] To more clearly illustrate the specific embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the module connection relationship of the present invention; Figure 2 This is a schematic diagram of the processing flow of the present invention. Detailed Implementation

[0018] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" 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 invention based on the specific circumstances.

[0021] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0022] like Figure 1 and Figure 2 An automated production system for polymer solid microneedles is shown, comprising: an automated conveying unit; the production system further comprising, sequentially connected along the automated conveying unit, a raw material pretreatment module, a dot-matrix automatic quantitative feeding module, a pressure molding module, a cooling and shaping module, and a demolding and sorting module; the raw material pretreatment module is used to melt the required raw materials and convey them to the dot-matrix automatic quantitative feeding module; the dot-matrix automatic quantitative feeding module is used to fill the molten polymer after molten treatment into a mold and convey it to the pressure molding module; the pressure molding module is used to press-shape the molten polymer filled into the mold and convey it to the cooling and shaping module; the cooling and shaping module is used to cool and shape the mold after pressure molding and convey it to the demolding and sorting module; the demolding and sorting module demolds and sorts the molds after cooling and shaping; the dot-matrix automatic quantitative feeding module integrates a temperature-controlled feeding unit; the production system also includes a branch module connected to the demolding and sorting module, which is used to irradiate and sterilize qualified products and recycle defective products after sorting by the demolding and sorting module.

[0023] The aforementioned automated production system for polymer solid microneedles integrates a series of automated conveying units, a raw material pretreatment module, a matrix-type automatic quantitative feeding module, a pressure molding module, a cooling and shaping module, and a demolding and sorting module. This achieves a seamless process from raw material handling to manufacturing, with strong continuity between each step, forming a continuous production line to meet large-scale production demands. The matrix-type automatic quantitative feeding module also features an independent temperature-controlled feeding unit, precisely controlling the temperature to adjust the polymer melt viscosity to adapt to the processing characteristics of different raw materials. Furthermore, it allows for the controllable construction of single-layer or multi-layer multifunctional composite solid microneedles within a single microneedle cavity, improving the accuracy and uniformity of feeding. The demolding and sorting module enables synchronous real-time detection and sorting, providing dynamic feedback. A branch module irradiates and sterilizes qualified products after demolding and sorting, or recycles and reprocesses defective products, achieving resource recycling.

[0024] like Figure 1 and Figure 2 As shown, in this embodiment, the branch module includes a qualified product irradiation sterilization module and a defective product recycling module. The qualified product irradiation sterilization module is connected to the demolding and sorting module, and is used to irradiate and sterilize qualified products sorted by the demolding and sorting module. The defective product recycling module is connected to both the demolding and sorting module and the raw material pretreatment module, and is used to transport unqualified products sorted by the demolding and sorting module to the raw material pretreatment module. The branch module also includes a qualified product packaging module, which is connected to the qualified product irradiation sterilization module. The qualified product packaging module is used to automatically package the irradiated and sterilized qualified products. The qualified products automatically enter the electron beam or gamma ray irradiation sterilization chamber through an automated conveying unit, and are sterilized at a preset dose. After sterilization, the sterilization dosage is monitored and recorded online. The sterilized microneedle array directly enters the qualified product automatic packaging module. The automatic packaging module is located in a Class 100 clean environment and is equipped with a local Class A laminar flow hood. Robots automatically complete the processes of microneedle plate picking and placing, blister packing, Tyvek cap heat sealing, labeling, and boxing, achieving aseptic and automated packaging. In the defective product recycling process, the core lies in physical recycling and regranulation. Specifically, the collected defective products are processed into fine particles by a pulverizer, and then replasticized, impurities are filtered, and extruded and granulated by a melt extruder at a controlled temperature to obtain recycled raw material particles. These recycled particles can be premixed with fresh raw materials in a certain proportion in the pretreatment module and reused in the production line.

[0025] like Figure 1 and Figure 2As shown, in this embodiment, the production system also includes a central control unit. The central control unit is connected to the raw material pretreatment module, the dot-matrix automatic quantitative feeding module, the pressure molding module, the cooling and shaping module, the demolding and sorting module, the qualified product irradiation sterilization module, the defective product recycling module, and the qualified product packaging module. The central control unit has a preset process parameter formula library for different types of thermoplastic polymer raw materials. The raw materials include polycaprolactone, polylactic acid, and polymethyl methacrylate. The thermoplastic polymer raw materials are selected from any one of polycaprolactone (PCL), polylactic acid (PLA), and polymethyl methacrylate (PMMA). The process parameter formula includes at least: the temperature setting value of the sample injection syringe for the dot-matrix automatic quantitative feeding module, and the molding temperature and molding pressure setting values ​​for the pressure molding module. The central control unit also incorporates a central intelligent control and data management platform, which integrates the Manufacturing Execution System (MES) and the Supervisory Control and Data Acquisition (SCADA) system. It is the command center of the system, and its functions include: formula and material management: storing and calling up the complete set of process parameters and material properties for different materials and products. Data-driven, end-to-end visualized monitoring and traceability: Real-time display of equipment status, process curves, and quality data, recording information throughout the entire process from raw materials to finished products; Intelligent feedback closed-loop control: Receives defect data from the sorting unit and, through statistical process analysis or machine learning models, automatically or suggest adjustments to upstream process parameters to achieve adaptive optimization; Predictive maintenance and digital twin: Analyzes key equipment operating data to provide early warnings of faults and can construct a 3D digital twin model of the production line for virtual debugging and process simulation; Adaptive production scheduling: Dynamically coordinates the rhythm of each module, responds to anomalies such as short shutdowns, and ensures continuous and stable operation of the entire line; By integrating automatic sorting, online sterilization, and intelligent recycling and remanufacturing modules, a complete closed loop from production, quality inspection, sterilization to waste recycling is constructed. This not only ensures the aseptic safety and packaging standardization of products at the end, complying with medical device regulations; but also transforms production waste into valuable secondary raw materials through the crushing, melting, and regranulation recycling of defective products, directly reducing raw material costs, reducing industrial solid waste, and significantly improving the resource utilization, economy, and environmental friendliness of the entire production system.

[0026] like Figure 1 and Figure 2 As shown, in this embodiment, the defective product recycling module includes a crushing unit, a melt extrusion unit, and a granulation unit connected in sequence. The crushing unit is connected to the demolding and sorting module, and the output end of the granulation unit is connected to the input end of the raw material pretreatment module, forming a material circulation loop. The crushing unit is used to crush the defective products sorted by the demolding and sorting module, the melt extrusion unit is used to melt extrude the crushed defective products, and the granulation unit is used to granulate the melt extruded defective products and transport them to the raw material pretreatment module.

[0027] like Figure 1 and Figure 2 As shown in this embodiment, the raw material pretreatment module includes an automatic feeding unit, a vacuum drying unit, and a precision melt plasticizing unit connected in sequence. The automatic feeding unit is connected to the granulation unit, and the precision melt plasticizing unit is connected to the dot matrix automatic quantitative feeding module. The automatic feeding unit is used to weigh and mix the new raw material with the recycled raw material granules processed by the granulation unit according to the ratio and transport them to the vacuum drying unit. The vacuum drying unit is used to remove moisture from the mixed raw material (temperature, vacuum degree, and time are automatically controlled) and transport it to the precision melt plasticizing unit. The precision melt plasticizing unit is used to melt the moisture-removed raw material and transport it to the dot matrix automatic quantitative feeding module. The precision melt plasticizing unit (such as a twin-screw extruder, whose barrel is divided into multiple independent temperature zones (such as zones 6-8), adopts PID precise temperature control (accuracy ±1℃)). Each temperature zone of this unit is independently temperature controlled and is equipped with melt pressure and temperature sensors. The data is fed back to the central control unit to achieve closed-loop stable control of the melting state. Its continuous output capacity is ≥10 kg / h, providing material guarantee for high-speed continuous production.

[0028] like Figure 1 and Figure 2As shown, in this embodiment, the production system also includes a machine vision inspection system, which is integrated into the demolding and sorting module. The machine vision inspection system is used to identify and sort qualified and defective products online. The machine vision inspection system and the central control unit form an intelligent feedback control loop. The machine vision inspection system can identify and classify defective products by type. The central control unit automatically adjusts the process parameters of the upstream related modules based on the received statistical data on defect types and quantities. Specifically, the adjustment logic of the intelligent feedback control loop formed by the machine vision inspection system and the central control unit includes: if the proportion of defects such as "insufficient filling" or "needle tip defects" exceeds the standard, the injection pressure of the dot matrix automatic quantitative feeding module is increased, or the molding temperature and molding pressure of the pressurized molding module are increased; if the proportion of defects such as "flash or burr" exceeds the standard, the molding pressure of the pressurized molding module is decreased; if the proportion of defects such as "needle body bending" exceeds the standard, the molding pressure of the pressurized molding module is decreased; if the proportion of defects such as "needle body bending" exceeds the standard, the molding pressure of the pressurized molding module is decreased. If the proportion of "curved" defects exceeds the standard, the cooling rate of the cooling and shaping module is adjusted; the pressure molding module integrates an automatic mold locking device; the cooling and shaping module is a multi-temperature zone programmable cooling station capable of executing programmed cooling curves; the automated conveyor unit is designed with a production cycle of ≤15 seconds / mold, and has an annual production capacity of over 1 million microneedle patches in continuous production mode; the automated conveyor unit carries the carriers of the microneedle molds, which pass through each module sequentially. Through the conveyor devices and carrier settings, the originally isolated processes are integrated into a continuous production line, realizing fully automated and uninterrupted production from raw materials to finished products, significantly improving manufacturing efficiency and providing a reliable process foundation for large-scale mass production; the conveyor unit uses high-precision synchronous belts or double-chain conveyor lines, and the entire system operates in a closed Class 10,000 clean environment. The conveyor line is driven by a servo motor and equipped with a high-resolution encoder to realize the start, stop, speed change, and position control of the carriers (positioning accuracy ±0.1). The production line is segmented and controlled by independent PLCs, communicating in real time with a central control system (such as a SCADA system). The carrier system is made of high-temperature and corrosion-resistant aluminum alloy or engineering ceramic material. The top is equipped with precision positioning pins and clamping mechanisms to fix the micro-needle mold (usually made of silicone, glass or metal). The bottom of the carrier is embedded with an RFID chip or QR code to uniquely identify and store the process parameters, production batch and other information of the station during the flow process.

[0029] like Figure 1 and Figure 2As shown, in this embodiment, the temperature-controlled feeding unit is a multi-channel heating and sampling device, which also integrates a vision positioning system. The temperature-controlled feeding unit is integrated into a dot-matrix automatic quantitative feeding module. The multi-channel heating and sampling device is specifically a multi-channel heatable sampling injector. The multi-channel heatable sampling injector has at least two independent material channels, each of which is equipped with an independent heating element and a temperature sensor. The sampling injector is mounted on a multi-axis linkage robotic arm. The vision positioning system is specifically a mold vision positioning system, used to identify the mold position and guide the robotic arm to achieve precise alignment and feeding. The polymer melt viscosity is adjusted by precisely controlling the temperature of the injection syringe with an independent temperature control system to adapt to the processing characteristics of different raw materials. The injection syringe is structurally modified to have a multi-channel or parallel injection syringe array, enabling simultaneous, co-positioning, and precise injection of two or more different polymer raw materials or polymer / drug mixtures. By independently controlling the material temperature, flow rate, and injection sequence of each channel, the controllable construction of single-layer or multi-layer multifunctional composite solid microneedles can be achieved within a single microneedle cavity. A mold vision positioning system automatically identifies the material before injection. It compensates for mold position and drives the syringe array to achieve rapid, precise alignment and parallel filling with the microporous cavity to meet high-cycle production requirements. Through independent temperature control and multi-material channel integration design of the injection syringe, it can not only flexibly set and maintain the optimal processing temperature for polymers with different melting points such as polycaprolactone, polylactic acid, and polymethyl methacrylate, ensuring high-precision and repeatable quantitative filling, but also expands the functionality of the process. It can precisely load active drugs, functional fillers, or another polymer into the solid microneedle, realizing the active design and flexible control of the microneedle's mechanical properties, degradation behavior, and drug release kinetics, thereby meeting diverse clinical application needs. Moreover, during the pressure molding process in the pressure molding module, the preset process parameter combination is called according to the type of polymer material used for molding. The process parameters include at least molding temperature and molding pressure. By pre-storing optimized process formulas for different materials, the corresponding parameters can be quickly called when switching production materials. For example, a higher temperature and pressure can be used for polymethyl methacrylate, and a lower temperature and pressure can be used for polycaprolactone, so that various materials can be molded within their optimal process window, significantly improving the flexibility of the production system and product yield.

[0030] like Figure 1 and Figure 2As shown in this embodiment, during the demolding and sorting process, the demolding and sorting module first uses a servo-controlled ejection mechanism to automatically demold. After the carrier arrives, a servo motor drives a pusher plate with a precision ejector pin array to smoothly eject the micro-needle array with a programmable motion curve. After ejection, the micro-needle array is immediately sent to the inspection platform, which is equipped with multi-angle light sources and multiple high-speed cameras to perform multi-view 3D morphological scanning. The system has a built-in intelligent algorithm based on convolutional neural networks (CNN) that can determine qualified products in real time and automatically classify and analyze defective products (needle tip defects, insufficient filling, etc.). Then, a high-speed sorting robot (such as a parallel robot or a multi-nozzle Cartesian robot) linked with the vision system sorts the product. Based on the judgment results, qualified and defective products are transferred to different conveyor branches, with a sorting cycle of less than 3 seconds to ensure smooth production. The central control unit performs statistical analysis on defect data. When the defect rate of a certain type exceeds the warning threshold, it can automatically send instructions to the corresponding upstream modules (such as feeding and forming modules) to fine-tune relevant process parameters, forming an intelligent feedback closed loop of "detection-analysis-optimization". This ensures ultra-high product consistency under large-scale production. Online visual inspection realizes real-time quality monitoring and sorting in the production process, preventing defective products from flowing into subsequent stages. At the same time, it provides real-time data feedback for closed-loop optimization of process parameters, which helps to continuously improve production quality and stability.

[0031] like Figure 1 and Figure 2 As shown, the present invention also includes an automated production process for polymer solid microneedles, which is based on an automated production system for polymer solid microneedles as described in any of the above claims, and the process includes the following steps: Step S1: The raw materials to be processed are melted in the raw material pretreatment module and then conveyed to the dot matrix automatic quantitative feeding module; Step S2: The molten polymer after melting treatment is filled into the mold and conveyed to the pressure molding module through the dot matrix automatic quantitative feeding module; Step S3: The molten polymer filled into the mold is pressurized and molded by the pressure molding module and then conveyed to the cooling and shaping module; Step S4: The mold formed under pressure is cooled and shaped by the cooling and shaping module and then conveyed to the demolding and sorting module. Step S5: Demolding and sorting the cooled and shaped molds using the demolding and sorting module; Step S6: The qualified products sorted by the demolding and sorting module are irradiated, sterilized, packaged, and the defective products are recycled through the branch line module. Specifically, Step S1: The carrier carrying the microneedle mold is placed on the automated conveying unit and conveyed sequentially. The polymer raw material to be processed is melted in the raw material pretreatment module and then conveyed to the dot matrix automatic quantitative feeding module. Step S2: The molten polymer after melting treatment is quantitatively filled into the microporous cavity of the mold and transported to the pressure molding module through the dot matrix automatic quantitative feeding module; Step S3: The molten polymer filled into the mold is pressurized and molded by the pressure molding module and then conveyed to the cooling and shaping module; Step S4: The mold formed under pressure is cooled and shaped by the cooling and shaping module and then conveyed to the demolding and sorting module. Step S5: The cooled and shaped mold is demolded and sorted online through the demolding and sorting module to obtain qualified products and defective products; Step S6: The qualified products sorted by the demolding and sorting module are irradiated and sterilized by the qualified product irradiation sterilization module. The qualified product packaging module automatically packages the irradiated and sterilized qualified products. The defective product recycling module crushes, melts and extrudes, and granulates the unqualified products sorted by the demolding and sorting module in sequence to obtain recycled raw materials which are then transported to the raw material pretreatment module. The polymer raw material in step S1 includes fresh raw material particles that are automatically mixed in a preset ratio and recycled raw material particles from the defective product recycling module in step S6. In step S2, the dot matrix automatic quantitative feeding module feeds materials through a multi-channel heated sample injector. By independently controlling the temperature, flow rate and injection sequence of the materials in each channel, two different polymer raw materials or a mixture of polymer and drug are simultaneously injected into the same mold cavity to form a single-layer or multi-layer microneedle structure. In steps S3 and S4, the pressure molding module and the cooling and shaping module need to retrieve the corresponding molding temperature, molding pressure, and cooling program parameters from the process parameter formula library pre-stored in the central control unit according to the type of polymer material selected. The process parameters include: when the polymer material is polymethyl methacrylate, the molding temperature is 150~200℃ and the molding pressure is 20~40 MPa; when the polymer material is polycaprolactone, the molding temperature is 65-80℃ and the molding pressure is 5-15 MPa; when the polymer material is polylactic acid, the molding temperature is 170-210℃ and the molding pressure is 10-25 MPa. In step S5, the online machine vision inspection system performs real-time quality inspection and defect classification on the demolded microneedles, and automatically sorts them according to the inspection results; at the same time, the defect statistics are fed back to the central control unit, and when the defect rate of a certain type exceeds the warning threshold, the process parameters of the upstream steps are automatically fine-tuned. Processing and manufacturing according to the above process, the overall yield rate of the production process is maintained at over 98.5%, and it supports large-scale stable production of more than 1 million microneedle patches per year.

[0032] At the same time, based on the above process, various polymer raw materials were processed and produced; The first method involves the large-scale intelligent preparation of polycaprolactone (PCL) solid microneedles for the production of PCL microneedles. Production capacity and system design: The entire line is designed to be balanced based on a cycle time of ≤ 15 s; it adopts dual-station parallel feeding and sorting to improve throughput, and the raw material pretreatment unit has an output capacity of 12 kg / h to meet the needs of high-speed production; Raw material preparation and intelligent pretreatment: The central control unit calls the "polycaprolactone" formula; the automatic feeding unit accurately weighs and mixes fresh polycaprolactone granules and recycled granules at an 8:2 ratio; after vacuum drying (40℃, 4h), the material enters the twin-screw melting and plasticizing unit (65, 75, 75 °C), and the screw speed is automatically adjusted according to the melt pressure feedback; High-precision material feeding guided by vision: The mold is sent to the material feeding station by a high-speed conveyor belt; after position compensation by the vision positioning system, the six-axis robotic arm drives the 16-channel syringe array heated to 75 °C to descend synchronously and complete the quantitative filling of the entire mold. Pressure molding and controlled cooling: After the mold enters the molding station and is automatically locked, the hot press plate applies pressure according to a multi-segment curve (70 ℃, 8 MPa, holding pressure for 10 s); then it enters the 15 ℃ cold plate station for rapid cooling for 20 s; Intelligent sorting and process feedback: After the micro needles are ejected, they enter the high-speed vision inspection station. The image processing system analyzes the characteristics of each needle in real time and classifies defects. If the system detects that the defect rate of "needle tip blunting" in a continuous batch exceeds 0.5%, the central control unit will trigger an adjustment command to slightly increase the holding pressure of the molding module by 5%. The high-speed parallel robot sorts according to the real-time "defect map" with a sorting cycle of <3 seconds. Sterilization, packaging and closed-loop recycling: qualified products are automatically packaged after being sterilized by electron beam irradiation (25 kGy), and defective products are crushed, melt-extruded at low temperature (85 °C) and then granulated, and automatically returned to the raw material silo by a pneumatic conveying system; Summary of production capacity and yield: Based on a 15-second cycle time and 300 days × 20 hours of effective working time per year, the theoretical annual production capacity reaches 1.152 million pieces; combined with the intelligent feedback system to suppress process fluctuations in real time, stable mass production can be achieved and the yield rate can be maintained at a high level.

[0033] The second method involves the preparation of polylactic acid solid microneedles, which is used to produce polylactic acid microneedles. The crystallization characteristics of polylactic acid are optimized to ensure consistent quality under large-scale production. Process summary: The raw material is dried at 60℃ for 6 h and melted at 195℃; the feeding temperature is 190℃; the molding parameters are: 185℃, 18 MPa, and holding pressure for 8 s. Specialized production capacity and quality assurance design: Gradient cooling control: To achieve crystallization control under high cycle time, the cooling and shaping module adopts a two-stage high-speed programmed cooling (10℃ strong air cooling for 5 s → 25℃ slow cooling for 15 s), with the switching precisely timed by the central system; Targeted visual feedback: Polylactic acid is prone to warping due to uneven cooling. The vision system strengthens the detection of needle straightness. If the "bending" defect rate exceeds the standard, the system automatically extends the slow cooling time or adjusts the uniformity of air cooling. High reliability design: Due to the moisture sensitivity of polylactic acid, the raw material transportation and recycling and granulation processes are carried out in a strictly humidity-controlled environment (dew point < -40℃) to ensure the stability of materials in long-term continuous production; Capacity verification: Through parallel feeding and efficient segmented cooling design, the production line in this embodiment can also match a core cycle time of ≤15 seconds, supporting the annual production capacity target of one million pieces.

[0034] The third method: preparation of solid polymethyl methacrylate microneedles, used to produce polymethyl methacrylate microneedles; Process summary: The raw materials are dried at 85℃ for more than 8 hours and melted at 165℃; the feeding temperature is 160℃; a high-pressure molding strategy is adopted: 155℃, 35 MPa, holding pressure for 12 seconds; Specialized production capacity and quality assurance design: Balancing stress control with high-speed production: To avoid cracking caused by internal stress, the cooling station adopts a slow gradient cooling controlled by a program (e.g., cooling from 120℃ to 60℃ at 2℃ / s). This process is achieved through precise temperature control in multiple temperature zones. Although the cooling time is slightly longer, the overall cycle time is still controlled within the target range by optimizing the hot pressing efficiency and conveying speed. Precise defect feedback: The vision system integrates a transmittance uniformity detection module; if the number of "flash" defects increases, the system automatically reduces the molding pressure and alarms to check mold wear. High-value utilization of recycled materials: defective polymethyl methacrylate products are regranulated under strict temperature control (170 ± 1℃) to avoid thermal degradation; the recycled granules can be used in batches with lower requirements for optical performance, achieving optimal cost control under large-scale production.

[0035] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. An automated production system for polymer solid microneedles, comprising: An automated conveying unit is characterized in that the production system further includes a raw material pretreatment module, a dot-matrix automatic quantitative feeding module, a pressure molding module, a cooling and shaping module, and a demolding and sorting module connected sequentially along the automated conveying unit; the raw material pretreatment module is used to melt the raw materials to be processed and convey them to the dot-matrix automatic quantitative feeding module; the dot-matrix automatic quantitative feeding module is used to fill the molten polymer after melting into the mold and convey it to the pressure molding module; the pressure molding module is used to press and shape the molten polymer filled into the mold and convey it to the cooling and shaping module; the cooling and shaping module is used to cool and shape the mold after pressure molding and convey it to the demolding and sorting module; the demolding and sorting module demolds and sorts the mold after cooling and shaping; the dot-matrix automatic quantitative feeding module integrates a temperature-controlled feeding unit; the production system also includes a branch module, which is connected to the demolding and sorting module, and the branch module is used to irradiate and sterilize qualified products and recycle defective products after being sorted by the demolding and sorting module.

2. The automated production system for polymer solid microneedles according to claim 1, characterized in that, The branch module includes a qualified product irradiation sterilization module and a defective product recycling module; the qualified product irradiation sterilization module is connected to the demolding and sorting module, and is used to irradiate and sterilize qualified products sorted by the demolding and sorting module; the defective product recycling module is connected to both the demolding and sorting module and the raw material pretreatment module, and is used to transport unqualified products sorted by the demolding and sorting module to the raw material pretreatment module.

3. The automated production system for polymer solid microneedles according to claim 2, characterized in that, The branch module also includes a qualified product packaging module, which is connected to the qualified product irradiation sterilization module. The qualified product packaging module is used to automatically package the qualified products after irradiation sterilization.

4. The automated production system for polymer solid microneedles according to claim 3, characterized in that, The production system also includes a central control unit, which is connected to the raw material pretreatment module, the dot matrix automatic quantitative feeding module, the pressure molding module, the cooling and shaping module, the demolding and sorting module, the qualified product irradiation sterilization module, the defective product recycling module, and the qualified product packaging module.

5. The automated production system for polymer solid microneedles according to claim 2, characterized in that, The defective product recycling module includes a crushing unit, a melt extrusion unit, and a granulation unit connected in sequence. The crushing unit is connected to the demolding and sorting module, and the granulation unit is connected to the raw material pretreatment module. The crushing unit is used to crush the defective products sorted by the demolding and sorting module. The melt extrusion unit is used to melt extrude the crushed defective products. The granulation unit is used to granulate the melt extruded defective products and transport them to the raw material pretreatment module.

6. The automated production system for polymer solid microneedles according to claim 5, characterized in that, The raw material pretreatment module includes an automatic feeding unit, a vacuum drying unit, and a precision melting and plasticizing unit connected in sequence. The automatic feeding unit is connected to the granulation unit, and the precision melting and plasticizing unit is connected to the dot matrix automatic quantitative feeding module. The automatic feeding unit is used to weigh and mix the new raw material and the recycled raw material processed by the granulation unit in proportion and then transport them to the vacuum drying unit. The vacuum drying unit is used to remove moisture from the mixed raw material and then transport it to the precision melting and plasticizing unit. The precision melting and plasticizing unit is used to melt the moisture-removed raw material and then transport it to the dot matrix automatic quantitative feeding module.

7. The automated production system for polymer solid microneedles according to claim 1, characterized in that, The production system also includes a machine vision inspection system, which is integrated into the demolding and sorting module.

8. The automated production system for polymer solid microneedles according to claim 1, characterized in that, The temperature-controlled feeding unit is a multi-channel heating and sampling device, which also integrates a visual positioning system.

9. The automated production system for polymer solid microneedles according to claim 1, characterized in that, The raw materials for processing include polycaprolactone, polylactic acid, and polymethyl methacrylate.

10. An automated manufacturing process for polymer solid microneedles, the process being implemented based on an automated manufacturing system for polymer solid microneedles as described in any one of claims 1 to 9, characterized in that, The process includes the following steps: Step S1: The raw materials to be processed are melted in the raw material pretreatment module and then conveyed to the dot matrix automatic quantitative feeding module; Step S2: The molten polymer after melting treatment is filled into the mold and conveyed to the pressure molding module through the dot matrix automatic quantitative feeding module; Step S3: The molten polymer filled into the mold is pressurized and molded by the pressure molding module and then conveyed to the cooling and shaping module; Step S4: The mold formed under pressure is cooled and shaped by the cooling and shaping module and then conveyed to the demolding and sorting module. Step S5: Demolding and sorting the cooled and shaped molds using the demolding and sorting module; Step S6: The qualified products sorted by the demolding and sorting module are irradiated, sterilized, packaged, and the defective products are recycled through the branch line module.

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