A circuit board for an automatic medical injector

Abstract

The application discloses a circuit board for an automatic medical injector and a production process thereof, and particularly relates to the technical field of circuit board manufacturing. The circuit board for the automatic medical injector adopts an elastic bending-resistant substrate as a substrate, selects elastic metal as a raw material, adds polyether in synthetic fibers, has good mechanical physical properties and good temperature resistance, and adds plasticizers and organic silicon as an auxiliary. The circuit board has high and low temperature resistance, electrical insulation, oxidation resistance stability, and a reinforcing layer as metal rubber. The structure is stable, and the elastic bending-resistant substrate has good elasticity, toughness and bending resistance. The use of transparent film coating and protective film double-protects the upper surface of the circuit board body, has good protection effect, avoids the phenomenon that the surface of the elastic bending-resistant substrate is damaged due to damage of the transparent film coating, improves the structure of the circuit board body, and improves the safety function of the circuit board body.

Description

Technical Field

[0001] This invention relates to the field of circuit board manufacturing technology, specifically to a circuit board for an automated medical injector. Background Technology

[0002] Circuit boards are used in medical autoinjectors to connect components and drive the syringe. Circuit boards come in various names, including ceramic circuit boards, alumina ceramic circuit boards, aluminum nitride ceramic circuit boards, aluminum substrates, high-frequency boards, thick copper boards, impedance boards, rigid-flex boards, ultra-thin circuit boards, and printed circuit boards. Circuit boards miniaturize and simplify circuits, playing a crucial role in the mass production of fixed circuits and optimizing the layout of electrical appliances. As electronic products increasingly demand lighter, thinner, shorter, and smaller designs, printed circuit boards are evolving towards high precision, finer lines, and higher density to meet environmental requirements in SMT assembly machines. Printed circuit boards can be categorized as reverse-sided, double-sided, and multi-layer, among others.

[0003] A search revealed that the invention patent with publication number CN108566723B discloses a heat-dissipating circuit board for automotive central control, which can quickly and effectively dissipate heat from the circuit board, thereby ensuring the normal operation of the circuit board and extending its service life.

[0004] Traditional flexible printed circuit boards (PCBs) have a certain degree of flexibility, but frequent bending still poses a risk of breakage and has a short lifespan. The heat generated by the circuit layers during operation accumulates inside the PCB and cannot be dissipated, causing the circuit layers to age due to excessive temperature, which further reduces the lifespan of the flexible PCB.

[0005] To address the aforementioned issues, this paper proposes measures to improve the bending resistance and flexibility of circuit boards, prevent breakage during use, extend their service life, enhance heat dissipation, prevent aging due to excessive temperature, reduce operating costs, increase strength, and improve stability of circuit boards. Summary of the Invention

[0006] The purpose of this invention is to provide a circuit board for an automated medical injector. By using a flexible, bendable substrate as the base material, and selecting 30W4Cr2VA from elastic metals as the raw material, polyether is added to the synthetic fiber, resulting in good mechanical and physical properties and temperature resistance. Plasticizers and organosilicon are added as auxiliary agents, providing high and low temperature resistance, electrical insulation, and oxidation stability. The reinforcing layer is a metal-rubber structure with good elasticity. The use of multiple reinforcing layers significantly improves the elasticity, toughness, and bending resistance of the flexible, bendable substrate. A flexible copper wire plate is attached to the flexible, bendable substrate, and a transparent thin film coating and a protective film are applied, providing double protection to the upper surface of the circuit board. This provides excellent protection and prevents damage to the surface of the flexible, bendable substrate caused by damage to the transparent thin film coating. This improves the structure of the circuit board and enhances its safety function, thus solving the problems mentioned in the background art.

[0007] The present invention can be achieved through the following technical solution: a circuit board for an automatic medical injector, comprising a circuit board body, the circuit board body comprising an elastic bending resistant substrate disposed in the middle, a heat dissipation substrate being disposed on the upper and lower surfaces of the elastic bending resistant substrate by means of a flexible prepreg, flexible copper wire plates being attached to both the upper and lower outer surfaces of the heat dissipation substrate, a protective film being attached to the outer surface of the upper flexible copper wire plate, the circuit board body being attached to the outer surface of the protective film, and a buffer substrate being adsorbed onto the outer surface of the lower flexible copper wire plate, the buffer substrate being adsorbed and connected to the lower circuit board body;

[0008] The elastic bending-resistant substrate has several reinforcing layers inside, and the elastic bending-resistant substrate is made of elastic metal, plasticizer, organosilicon, resin and synthetic fiber.

[0009] The elastic metal is any one of 60Si2Mn, 50CrVA, and 30W4Cr2VA;

[0010] The resin adhesive includes 20-25% polyimide, 16-20% polytetrafluoroethylene, 15-30% polyvinyl chloride, 25-35% carbon fiber modified high-elasticity polyethylene, 8-10% modified graphene oxide, 25-40% acetone and 3-5% 4-methylimidazole.

[0011] The reinforcing layer is one of 0Cr18Ni9Ti and 1Cr18Ni9Ti.

[0012] A further technical improvement of the present invention is that: a plurality of heat-conducting rods are disposed through the interior of the elastic bending substrate, and the end of each heat-conducting rod is connected to the inner surface of the corresponding heat dissipation substrate.

[0013] A further technical improvement of the present invention is that: the interior of the elastic bending substrate has a plurality of through holes, and each through hole is coated with a conductive carbon paste layer, the conductive carbon paste layer connecting the upper and lower flexible copper wire plates.

[0014] A further technical improvement of the present invention is that the plasticizer is one of phthalate, aliphatic diester, fatty acid ester, polyphenol ester, polyol ester, epoxy hydrocarbon and alkyl sulfonate.

[0015] A further technical improvement of the present invention is that the organosilicon is a mixture of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane.

[0016] A further technical improvement of the present invention is that the synthetic fiber comprises 20-25% polyester fiber, 15-20% nylon fiber, 10-15% polyolefin elastic fiber, 3-5% polyether, 15-20% polyacrylonitrile fiber, 15-25% polyurethane elastic fiber, 10-15% polyamide fiber, and 25-35% carbon fiber modified high elastic polyethylene fiber.

[0017] A further technical improvement of the present invention is that several components are provided on both the upper and lower surfaces of the circuit board body.

[0018] The present invention also provides a manufacturing process for a circuit board for an automated medical injector, the manufacturing process comprising the following steps:

[0019] Step 1: Preparation of Resin Adhesive: Turn on the ice water circulation system of the mixing tank, set the ice water temperature to 0-10°C, add plasticizer, organosilicon, polyimide, polytetrafluoroethylene, polyvinyl chloride and carbon fiber modified high-elasticity polyethylene, stir for 100-150 minutes until the resin is completely dissolved in acetone; add modified graphene oxide to the dissolved mixture, turn on the homogenizer and shear press to circulate and stir for 60-90 minutes, and pass it through a molecular sieve filter press to adsorb and filter large particles in the mixture; add 4-methylimidazole to the filtered mixture, and then circulate and stir for 45-90 minutes to obtain the resin adhesive solution;

[0020] Step 2: Fabrication of the flexible bending-resistant substrate: First, select 30W4Cr2VA as the substrate for the circuit board. Then, mix the resin liquid, plasticizer, and silicone until homogeneous. Pour the mixed resin onto the synthetic fibers, completely immersing the gaps between the synthetic fibers. Press the synthetic fibers, several reinforcing layers, several heat-conducting rods, and the resin into a thin sheet. Place it in an oven for baking at a temperature of 60-120°C for 5-20 minutes to obtain the flexible bending-resistant substrate.

[0021] Step 3: Fabrication of carbon paste layer: Stack the flexible bending substrate, heat dissipation substrate and prepared flexible copper wire board, and hot press them at 200-250°C to form a multilayer board. Make through holes in the flexible copper wire board and polish it. Apply conductive carbon paste to the inner wall of the through holes to form a conductive carbon paste layer. Then solder the required components onto the surface of the flexible copper wire board.

[0022] Step 4: The upper surface of the multilayer board obtained in Step 3 is sequentially covered with a transparent protective film layer and the circuit board body. The lower surface of the multilayer board is sequentially covered with a buffer substrate and a transparent thin film coating, and then placed in an oven for baking at a temperature of 60-80°C for 5-20 minutes. Then, connection holes communicating with through holes are set on the upper and lower surfaces of the circuit board. The connection holes penetrate the transparent thin film coating, the protective film, and the buffer substrate and communicate with the through holes. After grinding and polishing, the circuit board of the automatic medical injector is obtained.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] In this invention, the circuit board of the automatic medical injector uses a flexible, bend-resistant substrate as the base material. 30W4Cr2VA, a flexible metal, is selected as the raw material. Polyether is added to the synthetic fiber, resulting in good mechanical and physical properties and temperature resistance. Plasticizers and organosilicon are added as auxiliary materials, providing resistance to high and low temperatures, electrical insulation, and oxidation stability. The reinforcing layer is a metal-rubber material, offering structural stability and good elasticity. The use of multiple reinforcing layers significantly improves the elasticity, toughness, and bending resistance of the flexible, bend-resistant substrate. A flexible copper wire plate is attached to the flexible, bend-resistant substrate, and a transparent thin film coating is applied. The protective film provides double protection to the upper surface of the circuit board, offering excellent protection and preventing damage to the elastic bending substrate surface caused by damage to the transparent film coating. This improves the structure of the circuit board and enhances its safety features. Conductive carbon paste separates and connects the copper wire layers, expanding the effective area of ​​the circuit board. The use of heat-conducting rods transfers heat to the heat dissipation substrate, which rapidly dissipates heat, significantly improving the working efficiency of the circuit board, extending its service life, and preventing damage to the circuit board structure due to heat accumulation. This, in turn, enhances the practicality and creativity of the circuit board. Attached Figure Description

[0025] To facilitate understanding by those skilled in the art, the present invention will be further described below with reference to the accompanying drawings.

[0026] Figure 1 This is a schematic diagram of the structure of the present invention;

[0027] Figure 2 This is a cross-sectional view of the circuit board body of the present invention.

[0028] In the diagram: 1. Circuit board body; 2. Transparent thin film coating; 3. Through hole; 4. Heat dissipation substrate; 5. Flexible bending substrate; 6. Reinforcing layer; 7. Heat-conducting rod; 8. Flexible copper wire board; 9. Buffer substrate; 10. Protective film. Detailed Implementation

[0029] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided. Example

[0030] Please see Figures 1-2 As shown, a circuit board for an automatic medical injector includes a circuit board body 1. The circuit board includes an elastic bending substrate 5 disposed in the middle. A heat dissipation substrate 4 is attached to the upper and lower surfaces of the elastic bending substrate 5 through a flexible prepreg. Flexible copper wire plates 8 are attached to both the upper and lower outer surfaces of the heat dissipation substrate 4. A protective film 10 is attached to the outer surface of the upper flexible copper wire plate 8. The circuit board body 1 is attached to the outer surface of the protective film 10. A buffer substrate 9 is adsorbed on the outer surface of the lower flexible copper wire plate 8. The buffer substrate 9 is adsorbed and connected to the lower circuit board body 1.

[0031] The flexible bending substrate 5 has several reinforcing layers 6 inside, and the flexible bending substrate 5 is made of elastic metal, plasticizer, silicone, resin and synthetic fiber;

[0032] The elastic metal is any one of 60Si2Mn, 50CrVA, and 30W4Cr2VA;

[0033] The resin adhesive comprises 20% polyimide, 16% polytetrafluoroethylene, 15% polyvinyl chloride, 25% carbon fiber modified high-elasticity polyethylene, 8% modified graphene oxide, 25% acetone and 3% 4-methylimidazole.

[0034] The reinforcing layer 6 is one of 0Cr18Ni9Ti and 1Cr18Ni9Ti.

[0035] Several heat-conducting rods 7 are disposed through the interior of the flexible bending substrate 5, and the end of each heat-conducting rod 7 is connected to the inner surface of the corresponding heat dissipation substrate 4.

[0036] The flexible bending substrate 5 has several through holes 3 inside, and each through hole 3 is coated with a conductive carbon paste layer on its wall surface. The conductive carbon paste layer connects the upper and lower flexible copper wire boards 8.

[0037] Several components are provided on both the upper and lower surfaces of the circuit board body 1.

[0038] The plasticizer is one of the following: phthalate, aliphatic diester, fatty acid ester, polyphenol ester, polyol ester, epoxy hydrocarbon and alkyl sulfonate.

[0039] Organosilicon is a mixture of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane.

[0040] The synthetic fibers include 20% polyester fiber, 15% nylon fiber, 10% polyolefin elastic fiber, 3% polyether, 15% polyacrylonitrile fiber, 15% polyurethane elastic fiber, 10% polyamide fiber, and 25% carbon fiber modified high elastic polyethylene fiber.

[0041] A manufacturing process for a circuit board used in an automated medical injector, the manufacturing process comprising the following steps:

[0042] Step 1: Preparation of Resin Adhesive: Turn on the ice water circulation system of the mixing tank, set the ice water temperature to 0-10°C, add polyimide, polytetrafluoroethylene, polyvinyl chloride and carbon fiber modified high-elasticity polyethylene, and stir for 100-150 minutes until the resin is completely dissolved in acetone; add modified graphene oxide to the dissolved mixture, turn on the homogenizer and shear press to circulate and stir for 60-90 minutes, and pass it through a molecular sieve filter press to adsorb and filter large particles in the mixture; add 4-methylimidazole to the filtered mixture, and then circulate and stir for 45-90 minutes to obtain the resin adhesive solution;

[0043] Step 2: Fabrication of the elastic bending-resistant substrate 5: First, select 30W4Cr2VA as the substrate for the circuit board. Then, mix and stir the resin liquid, plasticizer, and silicone. Pour the mixed resin onto the synthetic fibers and completely immerse the gaps between the synthetic fibers. Press the synthetic fibers, several reinforcing layers 6, several heat-conducting rods 7, and resin into a thin sheet and bake it in an oven at a temperature of 60-120°C for 5-20 minutes to obtain the elastic bending-resistant substrate 5.

[0044] Step 3: Fabrication of carbon paste layer: Stack the flexible bending substrate 5, heat dissipation substrate 4 and the prepared flexible copper wire board 8, and hot press them at 200-250°C to form a multilayer board. Make through holes 3 on the flexible copper wire board 8 and polish it. Apply conductive carbon paste to the inner wall surface of the through holes 3 to form a conductive carbon paste layer. Then solder the required components onto the surface of the flexible copper wire board 8.

[0045] Step 4: The upper surface of the multilayer board obtained in Step 3 is sequentially covered with a transparent protective film layer 10 and a circuit board body 1. The lower surface of the multilayer board is sequentially covered with a buffer substrate 9 and a transparent thin film coating 2, and then placed in an oven for baking at a temperature of 60-80°C for 5-20 minutes. Then, connection holes communicating with through holes 3 are set on the upper and lower surfaces of the circuit board. The connection holes penetrate the transparent thin film coating 2, the protective film 10, and the buffer substrate 9 and communicate with the through holes 3. After grinding and polishing, the circuit board of the automatic medical injector is obtained.

[0046] Example 1

[0047] The flexible bending substrate 5 has several reinforcing layers 6 inside, and the flexible bending substrate 5 is made of elastic metal, plasticizer, silicone, resin and synthetic fiber;

[0048] The elastic metal is any one of 60Si2Mn, 50CrVA, and 30W4Cr2VA;

[0049] The resin adhesive comprises 25% polyimide, 20% polytetrafluoroethylene, 30% polyvinyl chloride, 35% carbon fiber modified high-elasticity polyethylene, 10% modified graphene oxide, 40% acetone, and 5% 4-methylimidazole.

[0050] The reinforcing layer 6 is one of 0Cr18Ni9Ti and 1Cr18Ni9Ti.

[0051] Several heat-conducting rods 7 are disposed through the interior of the flexible bending substrate 5, and the end of each heat-conducting rod 7 is connected to the inner surface of the corresponding heat dissipation substrate 4.

[0052] The flexible bending substrate 5 has several through holes 3 inside, and each through hole 3 is coated with a conductive carbon paste layer on its wall surface. The conductive carbon paste layer connects the upper and lower flexible copper wire boards 8.

[0053] Several components are provided on both the upper and lower surfaces of the circuit board body 1.

[0054] The plasticizer is one of the following: phthalate, aliphatic diester, fatty acid ester, polyphenol ester, polyol ester, epoxy hydrocarbon and alkyl sulfonate.

[0055] Organosilicon is a mixture of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane, or methylphenyldichlorosilane.

[0056] The synthetic fibers include 25% polyester fiber, 20% nylon fiber, 15% polyolefin elastic fiber, 5% polyether, 20% polyacrylonitrile fiber, 25% polyurethane elastic fiber, 15% polyamide fiber, and 35% carbon fiber modified high elastic polyethylene fiber.

[0057] A manufacturing process for a circuit board used in an automated medical injector, the manufacturing process comprising the following steps:

[0058] Step 1: Preparation of Resin Adhesive: Turn on the ice water circulation system of the mixing tank, set the ice water temperature to 0-10°C, add polyimide, polytetrafluoroethylene, polyvinyl chloride and carbon fiber modified high-elasticity polyethylene, and stir for 100-150 minutes until the resin is completely dissolved in acetone; add modified graphene oxide to the dissolved mixture, turn on the homogenizer and shear press to circulate and stir for 60-90 minutes, and pass it through a molecular sieve filter press to adsorb and filter large particles in the mixture; add 4-methylimidazole to the filtered mixture, and then circulate and stir for 45-90 minutes to obtain the resin adhesive solution;

[0059] Step 2: Fabrication of the elastic bending-resistant substrate 5: First, select 30W4Cr2VA as the substrate for the circuit board. Then, mix and stir the resin liquid, plasticizer, and silicone. Pour the mixed resin onto the synthetic fibers and completely immerse the gaps between the synthetic fibers. Press the synthetic fibers, several reinforcing layers 6, several heat-conducting rods 7, and resin into a thin sheet and bake it in an oven at a temperature of 60-120°C for 5-20 minutes to obtain the elastic bending-resistant substrate 5.

[0060] Step 3: Fabrication of carbon paste layer: Stack the flexible bending substrate 5, heat dissipation substrate 4 and the prepared flexible copper wire board 8, and hot press them at 200-250°C to form a multilayer board. Make through holes 3 on the flexible copper wire board 8 and polish it. Apply conductive carbon paste to the inner wall surface of the through holes 3 to form a conductive carbon paste layer. Then solder the required components onto the surface of the flexible copper wire board 8.

[0061] Step 4: The upper surface of the multilayer board obtained in Step 3 is sequentially covered with a transparent protective film layer 10 and a circuit board body 1. The lower surface of the multilayer board is sequentially covered with a buffer substrate 9 and a transparent thin film coating 2, and then placed in an oven for baking at a temperature of 60-80°C for 5-20 minutes. Then, connection holes communicating with through holes 3 are set on the upper and lower surfaces of the circuit board. The connection holes penetrate the transparent thin film coating 2, the protective film 10, and the buffer substrate 9 and communicate with the through holes 3. After grinding and polishing, the circuit board of the automatic medical injector is obtained.

[0062] In this invention, the circuit board of the automatic medical injector uses an elastic bending-resistant substrate 5 as the substrate, and selects 30W4Cr2VA from elastic metals as the raw material. Polyether is added to the synthetic fiber, resulting in good mechanical and physical properties and good temperature resistance. Plasticizers and organosilicon are added as auxiliary materials, providing resistance to high and low temperatures, electrical insulation, and oxidation stability. The reinforcing layer 6 is a metal-rubber material with stable structure and good elasticity. The use of multiple reinforcing layers 6 significantly improves the elasticity, toughness, and bending resistance of the elastic bending-resistant substrate 5. A flexible copper wire plate 8 is attached to the elastic bending-resistant substrate 5, and a transparent thin film coating 2 and a protective film 10 are applied to the circuit board. The upper surface of the circuit board body 1 is double-protected, providing excellent protection and preventing damage to the surface of the elastic bending substrate 5 caused by damage to the transparent thin film coating 2. This improves the structure of the circuit board body 1 and enhances its safety function. The copper wire layer is separated and connected by conductive carbon paste, expanding the effective area of ​​the circuit board body 1. The use of heat-conducting rods 7 transfers heat to the heat dissipation substrate 4. The rapid heat dissipation of the heat dissipation substrate 4 can significantly improve the working efficiency of the circuit board body 1, extend its service life, and prevent the circuit board from being damaged by heat accumulation. This improves the practicality and creativity of the circuit board, and has good market prospects and application value.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A circuit board for an automated medical injector, comprising a circuit board body (1), characterized in that: The circuit board includes an elastic bending substrate (5) disposed in the middle. A heat dissipation substrate (4) is attached to the upper and lower surfaces of the elastic bending substrate (5) by means of a flexible prepreg. Flexible copper wire plates (8) are attached to the upper and lower outer surfaces of the heat dissipation substrate (4). A protective film (10) is attached to the outer surface of the upper flexible copper wire plate (8). A circuit board body (1) is attached to the outer surface of the protective film (10). A buffer substrate (9) is adsorbed on the outer surface of the lower flexible copper wire plate (8). The buffer substrate (9) is adsorbed and connected to the lower circuit board body (1). The elastic bending substrate (5) has several reinforcing layers (6) inside, and the elastic bending substrate (5) is made of elastic metal, plasticizer, organosilicon, resin and synthetic fiber; The elastic metal is any one of 60Si2Mn, 50CrVA, and 30W4Cr2VA; The resin adhesive includes 20-25% polyimide, 16-20% polytetrafluoroethylene, 15-30% polyvinyl chloride, 25-35% carbon fiber modified high-elasticity polyethylene, 8-10% modified graphene oxide, 25-40% acetone and 3-5% 4-methylimidazole. The reinforcing layer (6) is one of 0Cr18Ni9Ti and 1Cr18Ni9Ti; Synthetic fibers include 20-25% polyester fiber, 15-20% nylon fiber, 10-15% polyolefin elastic fiber, 3-5% polyether, 15-20% polyacrylonitrile fiber, 15-25% polyurethane elastic fiber, 10-15% polyamide fiber, and 25-35% carbon fiber modified high-elasticity polyethylene fiber.

2. The circuit board for an automated medical injector according to claim 1, characterized in that, The interior of the elastic bending substrate (5) is provided with a number of heat-conducting rods (7), and the end of each heat-conducting rod (7) is connected to the inner surface of the corresponding heat dissipation substrate (4).

3. The circuit board for an automated medical injector according to claim 1, characterized in that, The flexible bending substrate (5) has several through holes (3) inside. Each through hole (3) is coated with a conductive carbon paste layer on its wall surface. The conductive carbon paste layer connects the upper and lower flexible copper wire plates (8).

4. A circuit board for an automated medical injector according to claim 1, characterized in that, The plasticizer is one of the following: phthalate, aliphatic diester, fatty acid ester, polyphenol ester, polyol ester, epoxy hydrocarbon and alkyl sulfonate.

5. A circuit board for an automated medical injector according to claim 1, characterized in that, Organosilicon is a mixture of methyltrichlorosilane, dimethyldichlorosilane, phenyltrichlorosilane, diphenyldichlorosilane and methylphenyldichlorosilane.

6. A circuit board for an automated medical injector according to claim 1, characterized in that, The circuit board body (1) has several components on both its upper and lower surfaces.

7. A manufacturing process for a circuit board for an automated medical injector as described in any one of claims 1-6, characterized in that, The production process includes the following steps: Step 1: Preparation of Resin Adhesive: Turn on the ice water circulation system of the mixing tank, set the ice water temperature to 0-10°C, add polyimide, polytetrafluoroethylene, polyvinyl chloride and carbon fiber modified high-elasticity polyethylene, and stir for 100-150 minutes until the resin is completely dissolved in acetone; add modified graphene oxide to the dissolved mixture, turn on the homogenizer and shear press to circulate and stir for 60-90 minutes, and pass it through a molecular sieve filter press to adsorb and filter large particles in the mixture; add 4-methylimidazole to the filtered mixture, and then circulate and stir for 45-90 minutes to obtain the resin adhesive solution; Step 2: Making the elastic bending substrate (5): First, select 30W4Cr2VA as the substrate of the circuit board. Then, mix the resin liquid, plasticizer and silicone evenly. Pour the mixed resin glue onto the synthetic fiber and completely immerse the gaps between the synthetic fibers. Press the synthetic fiber, several reinforcing layers (6), several heat-conducting rods (7) and resin glue into a thin plate and bake it in an oven at a temperature of 60-120°C for 5-20 minutes to obtain the elastic bending substrate (5). Step 3: Make carbon paste layer: Stack the flexible bending substrate (5), heat dissipation substrate (4) and prepared flexible copper wire board (8) and hot press them at 200-250°C to form a multilayer board. Make through holes (3) on the flexible copper wire board (8) and polish it. Apply conductive carbon paste to the inner wall of the through holes (3) to form a conductive carbon paste layer. Then solder the required components onto the surface of the flexible copper wire board (8). Step 4: The upper surface of the multilayer board obtained in step 3 is covered with a transparent protective film (10) and the circuit board body (1) in sequence. The lower surface of the multilayer board is covered with a buffer substrate (9) and a transparent thin film coating (2) in sequence and then placed in an oven for baking. The baking temperature is 60-80°C and the baking time is 5-20 minutes. Then, a connection hole communicating with the through hole (3) is set on the upper and lower surfaces of the circuit board. The connection hole passes through the transparent thin film coating (2), the protective film (10) and the buffer substrate (9) and communicates with the through hole (3). After grinding and polishing, the circuit board of the automatic medical injector is obtained.

Images