Buried resistive heat paste protective film, method for manufacturing the same, and method for manufacturing circuit board

Abstract

The application relates to a buried resistance heat paste protection film and a manufacturing method thereof and a manufacturing method of a circuit board, the buried resistance heat paste protection film comprising, from top to bottom, a base film layer, an acrylic glue layer and a release film layer; the acrylic glue layer comprises the following raw materials in mass fractions: 100 parts of acrylate pressure-sensitive glue, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of an epoxy curing agent, 0.9-1.1 parts of an epoxy active toughening agent and 0.4-0.6 parts of an epoxy accelerator. The protection film is specially provided for the buried resistance of the circuit board, can isolate the positions of the PCB substrate which do not need to be printed, and can make the solidified electronic components in the form of a column with a set height value to meet the requirements.

Description

[Technical Field] This invention relates to layered products, particularly to layered products actually composed of synthetic resins, especially to protective films for use on printed circuit boards, and also to methods for manufacturing such protective films. [Background Technology] With the development of 5G technology, communication service systems and personal consumer electronics products are increasingly trending towards higher frequencies, higher speeds, higher power, smaller sizes, and more multifunctionality. This places increasingly higher demands on the frequency and heat dissipation requirements of printed circuit boards (PCBs). Embedded capacitor and resistor technology has become a widely adopted method in the PCB industry to increase PCB frequency, improve heat dissipation, and reduce PCB size. Embedded capacitor and resistor technology offers advantages such as reducing PCB size and weight, saving costs, improving impedance matching of circuits, reducing signal crosstalk, noise, and electromagnetic interference, and shortening signal transmission paths. Commonly used embedded capacitor and resistor technologies include etching, chemical plating, and printing. The specific operation of the printing method is as follows: Holes are mechanically drilled into the insulating medium of the PCB substrate to which the embedded capacitors and resistors are to be embedded. Then, the electronic components are filled into the insulating medium of the PCB substrate through printing. After curing, electronic component pillars are formed, with each end of the pillar protruding a certain distance from the PCB substrate. Finally, a PP prepreg is used to laminate the PCB substrate with the electronic component pillars to the conductive layer, achieving the purpose of embedding capacitors and resistors. The electronic components to be embedded include capacitors and / or resistors, referred to as embedded capacitors and resistors. The following problems are encountered when embedding electronic components using the printing method: First, how to ensure that electronic components are precisely positioned on the PCB substrate where they need to be printed and buried during the printing method of landfilling, while isolating the areas on the PCB substrate that do not need to be printed and buried; Second, how to ensure that the cured electronic components are a certain distance above the PCB substrate. [Summary of the Invention] The technical problem to be solved by the present invention is to avoid the shortcomings of the prior art and provide a thermally insulating protective film for embedded capacitors and resistors, a method for manufacturing the same, and a method for manufacturing a circuit board. The thermally insulating protective film for embedded capacitors and resistors of the present invention is specifically provided for use when embedding capacitors and resistors in a circuit board. The thermally insulating protective film for embedded capacitors and resistors isolates the areas of the PCB substrate that do not need to be printed, and the protective film has a specified thickness, so that the cured electronic components will be in the form of pillars with a set height value to meet the requirements.

[0001] The technical solution adopted by the present invention to solve the aforementioned technical problem is as follows: A method for manufacturing an embedded capacitor-insulating heat-resistant protective film is provided. The embedded capacitor-insulating heat-resistant protective film includes, from top to bottom, a base film layer that provides support and maintains dimensional stability, an acrylic adhesive layer that provides adhesion, and a release film layer that provides release protection. The acrylic adhesive layer comprises the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent, and 0.4-0.6 parts of epoxy accelerator. The method for manufacturing the embedded capacitor-insulating heat-resistant protective film includes the following steps: Step 1: Weigh 18-22 parts by weight of epoxy resin and an equal amount of solvent, mix and dissolve to prepare a 50% solution for later use; in this step 1, the solvent is ethyl acetate; Step 2: Weigh 100 parts of acrylate pressure-sensitive adhesive by weight, add the acrylate pressure-sensitive adhesive to the solution prepared in Step 1, then add 30-40 parts of ethanol and 35-45 parts of solvent, and stir to disperse evenly; in this step 2, the solvent is ethyl acetate. Step 3: Add 0.4 to 0.6 parts of epoxy curing agent and stir to disperse evenly; the epoxy curing agent is polyetheramine; Step 4: Add 0.9 to 1.1 parts of epoxy active toughening agent and stir to disperse evenly; the epoxy active toughening agent is polypropylene glycol diglycidyl ester. Step 5: Add 0.4 to 0.6 parts of epoxy accelerator and stir to disperse evenly; the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol; Step 6: After filtering with a filter screen, obtain the acrylic adhesive solution and set aside for later use; Step 7: Apply the acrylic adhesive solution from Step 6 onto the base film layer, and then cure and dry it to obtain the acrylic adhesive layer set on the base film layer; Step 8: Lay a release film layer onto the acrylic adhesive layer; Step 9: Bake and cure, then cool and discharge to obtain the embedded thermal insulation protective film.

[0002] This invention also provides a heat-sensitive protective film for embedded capacitors and resistors on circuit boards. The heat-sensitive protective film comprises, from top to bottom, a base film layer that provides support and maintains dimensional stability, an acrylic adhesive layer that provides adhesion, and a release film layer that provides release protection. The acrylic adhesive layer comprises the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent, and 0.4-0.6 parts of epoxy accelerator. The solvent is ethyl acetate, and by mass, the ethyl acetate is 53-67 parts; the epoxy curing agent is polyetheramine, the epoxy active toughening agent is polypropylene glycol diglycidyl ester, and the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0003] The present invention also provides a method for manufacturing a buried capacitor and buried resistor circuit board, comprising the following steps: Step A, Applying the protective film: The embedded capacitor and thermal resist protective film includes, from top to bottom, a base film layer that provides support and maintains dimensional stability, an acrylic adhesive layer that provides adhesion, and a release film layer that provides release protection; the embedded capacitor and thermal resist protective film is cut to the same size as the PCB main substrate, then the release film layer of the embedded capacitor and thermal resist protective film is peeled off, and then the acrylic adhesive layer of the embedded capacitor and thermal resist protective film is applied to the upper and lower sides of the PCB main substrate respectively; Step B, mechanical drilling: Drill through holes on the PCB main substrate with the embedded capacitor and thermal insulation protective film pasted on the upper and lower sides. The number of through holes is the same as the number of electronic components to be embedded. The electronic components to be embedded include capacitors and / or resistors. Step C, Printing: Fill the corresponding through holes drilled in Step B with each electronic component using a printing method; Step D, Curing: The electronic component is cured in the through-hole of the PCB main substrate by baking according to the curing conditions of the electronic component. Step E, film peeling: After the electronic components are cured, peel off the acrylic adhesive layer and base film layer of the embedded capacitor and embedded thermal resist protective film on the upper and lower sides of the PCB main substrate. Step F, Stacking: The first upper PCB substrate, the second upper PCB substrate, the first lower PCB substrate, and the second lower PCB substrate are laminated together with the main PCB substrate to obtain a buried capacitor and resistor circuit board, wherein the second upper PCB substrate, the first upper PCB substrate, the main PCB substrate, the first lower PCB substrate, and the second lower PCB substrate are sequentially placed next to each other from top to bottom.

[0004] In step A, after the acrylic adhesive layer of the embedded capacitor and thermal resist protective film is pasted onto the upper and lower sides of the PCB main substrate, it is placed in a high-pressure press and pressed for a certain time at a certain temperature, thereby bonding the acrylic adhesive layer 20 of the embedded capacitor and thermal resist protective film to the PCB main substrate.

[0005] The total thickness of the base film layer and the acrylic adhesive layer is equal to the set height value of the electronic component above the upper or lower surface of the PCB main substrate, so that in step C, the top surface of each electronic component is flush with the upper surface of the base film layer of the embedded capacitor and embedded thermal resist protective film on the upper surface of the PCB main substrate, and the bottom surface of each electronic component is flush with the lower surface of the base film layer of the embedded capacitor and embedded thermal resist protective film on the lower surface of the PCB main substrate.

[0006] Compared with the prior art, the beneficial effects of the embedded capacitor and embedded thermal resist protective film, its manufacturing method, and the circuit board manufacturing method of the present invention are as follows: I. This invention designs a specific formula ratio and uses a special manufacturing method to produce a heat-adhesive protective film for embedded capacitors and resistors that meets the specified requirements at room temperature and a certain temperature, such as 80°C, for use on circuit boards when embedding capacitors and resistors. 2. By using the embedded capacitor and embedded resistor thermal adhesive protective film of the present invention, the electronic components that need to be embedded can be more accurately embedded in the required position of the PCB main substrate when manufacturing embedded capacitor and embedded resistor circuit boards. Third, by using the embedded capacitor and embedded resistor thermal adhesive protective film of the present invention, the shape of the electronic components that need to be embedded can be realized more flexibly when manufacturing embedded capacitor and embedded resistor circuit boards. IV. When using the embedded capacitor and embedded resistor thermal adhesive protective film of the present invention, the height of the electronic components to be embedded can be adjusted according to the thickness of the embedded capacitor and embedded resistor thermal adhesive protective film during the manufacturing of embedded capacitor and embedded resistor circuit boards, and the height of the electronic components to be embedded above the upper surface and / or lower surface of the PCB substrate can be guaranteed to be within the set range. 5. When using the embedded capacitor and embedded resistor thermal adhesive protective film of the present invention, the areas of the PCB substrate that do not need to be printed can be isolated during the manufacturing of embedded capacitor and embedded resistor circuit boards, effectively playing a role in isolation and protection. VI. By using the embedded capacitor and resistor thermal adhesive protective film of the present invention, the efficiency of embedding capacitors and resistors in the manufacturing of embedded capacitor and resistor circuit boards is improved and the cost is reduced.

[0007] In summary, the embedded capacitor and resistor thermal adhesive protective film of the present invention is specifically provided for use when embedding capacitors and resistors on circuit boards. The embedded capacitor and resistor thermal adhesive protective film isolates the areas of the PCB substrate that do not need to be printed, and the protective film has a specified thickness, so that the cured electronic components will be in the form of pillars with a set height value to meet the requirements. [Attached Image Description] Figure 1 This is a frontal sectional view of the embedded thermal insulation protective film of the present invention. Figure 2 This is a frontal sectional view of the acrylic adhesive layer and base film layer of the embedded capacitor and thermal resistive protective film when they are bonded together with the PCB main substrate of the embedded capacitor and thermal resistive circuit board (i.e., step A). Figure 3 This is a frontal sectional view of the acrylic adhesive layer and base film layer of the embedded capacitor and thermal resistive protective film after drilling holes are attached together with the PCB main substrate of the embedded capacitor and thermal resistive circuit board. Figure 4 The various electronic components are filled into Figure 3 A schematic diagram of the orthographic projection of the through hole (i.e., step C); Figure 5 yes Figure 4 A schematic diagram of the orthographic projection of the main section after the film has been torn off (i.e., step E); Figure 6 This is a schematic diagram of the orthographic projection of the main section view of the disassembled position before the lamination of the stacked plates in step F; Figure 7 This is a frontal sectional view of the embedded capacitor and resistor circuit board obtained after the stacking of the boards in step F.

Detailed Implementation Methods

[0008] See Figure 1 A method for manufacturing a heat-resistant embedded protective film, comprising, from top to bottom, a base film layer 10 for supporting and maintaining dimensional stability, an acrylic adhesive layer 20 for bonding, and a release film layer 30 for release protection; wherein the acrylic adhesive layer 20 comprises the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent, and 0.4-0.6 parts of epoxy accelerator; the method for manufacturing the heat-resistant embedded protective film includes the following steps: Step 1: Weigh 18-22 parts by weight of epoxy resin and an equal amount of solvent, mix and dissolve to prepare a 50% solution for later use; in Step 1, the solvent is ethyl acetate; the epoxy resin can be bisphenol A type epoxy resin E20. Step 2: Weigh 100 parts of acrylate pressure-sensitive adhesive by weight, add the acrylate pressure-sensitive adhesive to the solution prepared in Step 1, then add 30-40 parts of ethanol and 35-45 parts of solvent, and stir to disperse evenly; in this step 2, the solvent is ethyl acetate. Step 3: Add 0.4 to 0.6 parts of epoxy curing agent and stir to disperse evenly; the epoxy curing agent is polyetheramine, which can be polyetheramine of model ZD1200 produced by Zibo Zhengda Polyurethane Co., Ltd. or Zibo Zhengda New Material Technology Co., Ltd. Step 4: Add 0.9 to 1.1 parts of epoxy active toughening agent and stir to disperse evenly; the epoxy active toughening agent is polypropylene glycol diglycidyl ester. Step 5: Add 0.4 to 0.6 parts of epoxy accelerator and stir to disperse evenly; the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol; Step 6: After filtering with a filter screen, obtain the acrylic adhesive solution and set aside for later use; generally, a 400-mesh filter screen is sufficient. Step 7: Apply the acrylic adhesive solution from Step 6 onto the base film layer 10, and then cure and dry it to obtain the acrylic adhesive layer 20 disposed on the base film layer 10. During curing and drying, the temperature is controlled at 140℃~160℃ and the time is maintained at 0.5~2 minutes, for example, the temperature is controlled at 150℃ and the time is maintained at 1 minute. Step 8: Lay the release film layer 30 onto the acrylic adhesive layer 20; Step 9: Baking and curing, cooling and unloading to obtain the embedded thermal insulation protective film. During baking and curing, the temperature is controlled at 70℃~90℃ and the time is maintained at 40~60 hours. For example, the temperature is controlled at 80℃ and the time is maintained at 48 hours.

[0009] See Figure 1 The present invention also provides a heat-sensitive protective film for embedded capacitors and resistors on circuit boards. The heat-sensitive protective film comprises, from top to bottom, a base film layer 10 for supporting and maintaining dimensional stability, an acrylic adhesive layer 20 for adhesion, and a release film layer 30 for release protection. The acrylic adhesive layer 20 comprises the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent, and 0.4-0.6 parts of epoxy accelerator. The solvent is ethyl acetate, and by mass, the ethyl acetate is 53-67 parts; the epoxy curing agent is polyetheramine, the epoxy active toughening agent is polypropylene glycol diglycidyl ester, and the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

[0010] See Figures 1 to 7 The present invention also provides a method for manufacturing a buried capacitor and buried resistor circuit board, comprising the following steps: Step A, Apply the protective film: See Figure 1 and Figure 2The embedded capacitor and thermal resist protective film includes, from top to bottom, a base film layer 10 that provides support and maintains dimensional stability, an acrylic adhesive layer 20 that provides adhesion, and a release film layer 30 that provides release protection. The embedded capacitor and thermal resist protective film is cut to the same size as the PCB main substrate 91. Then, the release film layer 30 of the embedded capacitor and thermal resist protective film is peeled off. Next, the acrylic adhesive layer 20 of the embedded capacitor and thermal resist protective film is respectively pasted on the upper and lower surfaces of the PCB main substrate 91. Step B, Mechanical Drilling: See Figure 3 Through holes 911 are drilled on the PCB main substrate 91 on the upper and lower sides where the embedded capacitor and thermal insulation protective film is pasted. The number of through holes 911 is the same as the number of electronic components to be embedded. The electronic components to be embedded include capacitors and / or resistors to be embedded. Step C, Printing: See Figure 4 The electronic components 99 are then filled into the corresponding through holes 911 drilled in step B using a printing method; the printing method is existing technology and will not be described in detail here. Step D, Curing: See Figure 4 The electronic component 99 is cured in the through-hole 911 of the PCB main substrate 91 by baking according to the curing conditions of the electronic component; curing is also a prior art and will not be described in detail here; Step E, peeling off the film: See Figure 5 After the electronic component 99 is cured, the acrylic adhesive layer 20 and the base film layer 10 of the embedded capacitor and embedded thermal resist protective film on the upper and lower sides of the PCB main substrate 91 are peeled off. Step F, Laminate lamination: See Figure 6 and Figure 7 The first upper PCB substrate 92, the second upper PCB substrate 94, the first lower PCB substrate 93, and the second lower PCB substrate 95 are laminated together with the main PCB substrate 91 to obtain a buried capacitor and resistor circuit board. From top to bottom, the second upper PCB substrate 94, the first upper PCB substrate 92, the main PCB substrate 91, the first lower PCB substrate 93, and the second lower PCB substrate 95 are sequentially placed close together. Laminate lamination is also existing technology and will not be elaborated further here. The main PCB substrate 91 of this invention can be a prepreg (PP sheet) or a PCB core board, the first upper PCB substrate 92 and the first lower PCB substrate 93 can be prepregs (PP sheets), and the second upper PCB substrate 94 and the second lower PCB substrate 95 can be copper-clad laminates.

[0011] In step A, after the acrylic adhesive layer 20 of the embedded capacitor and thermal resist protective film is pasted onto the upper and lower sides of the PCB main substrate 91, it is placed in a high-pressure press and pressed for a certain time at a certain temperature, for example, pressing for 100 seconds at 80°C with a pressure of 30 kg, so that the acrylic adhesive layer 20 of the embedded capacitor and thermal resist protective film is pasted together with the PCB main substrate 91.

[0012] See Figure 1 , Figure 4 and Figure 5 The total thickness T of the base film layer 10 and the acrylic adhesive layer 20 is equal to the set height H of the electronic component 99 above the upper or lower surface of the PCB main substrate 91. This ensures that in step C, the top surface of each electronic component 99 is flush with the upper surface of the base film layer 10 of the embedded capacitor and thermal resist protective film on the upper surface of the PCB main substrate 91, and the bottom surface of each electronic component 99 is flush with the lower surface of the base film layer 10 of the embedded capacitor and thermal resist protective film on the lower surface of the PCB main substrate 91. This ensures that the height of the electronic component 99 above the upper and / or lower surface of the PCB main substrate 91 is within the set range. Generally, the height of electronic components above the upper or lower surface of the PCB main substrate 91 is set to 30 μm (micrometers). The total thickness T of the base film layer 10 and the acrylic adhesive layer 20 is 30 μm (micrometers). The thickness of the base film layer 10 is generally 25 μm (micrometers), the thickness of the acrylic adhesive layer 20 is generally 5 μm (micrometers), and the release film layer 30 is generally a transparent PET (polyethylene terephthalate) film with a thickness of 25 μm (micrometers).

[0013] The embedded capacitor and embedded thermal resist protective film, manufactured using the above-mentioned special formula and manufacturing method, has a base film layer 10 thickness of 25 μm, an acrylic adhesive layer 20 thickness of 5 μm, and a release film layer 30 thickness of 25 μm. After the release film layer 30 of the embedded capacitor and embedded thermal resist protective film is peeled off, the acrylic adhesive layer 20 of the embedded capacitor and embedded thermal resist protective film is then pasted onto the upper and lower sides of the PCB main substrate 91, respectively. The substrate is then placed in a high-pressure press and subjected to 30 kg of pressure at 80°C for 100 seconds. The peel force is tested, and the thermal peel force at 80°C is approximately 10 gf / inch, while the peel force at room temperature is 5 gf / inch. The peel force is within the peel range of the testing standard GB / T 2792-1998.

[0014] This invention provides a thermally bonded protective film for embedded capacitors and resistors, specifically designed for the entire process of embedding capacitors and resistors in circuit boards. The film is non-adhesive at room temperature, making it easy to use. When hot-pressed at a certain temperature, such as 80°C, it can adhere firmly to the insulating dielectric layer of the PCB substrate. After use, the adhesiveness is within the easy-to-peel range. Compared with traditional printing methods for embedding capacitors and resistors on circuit boards, the use of the thermally bonded protective film of this invention achieves the following effects: First, it can more accurately embed electronic components in the required positions; second, it can more flexibly realize the shape of the electronic components to be embedded. Generally, the shape of the electronic components to be embedded is a cube or cylinder, which can be drilled simply by drilling. The thermally bonded protective film of this invention will also present the corresponding shape, and other unnecessary positions will not be printed and filled; third, it can adjust the height of the electronic components to be embedded according to the thickness of the thermally bonded protective film, and can ensure that the height of the electronic components to be embedded above the upper and / or lower surfaces of the PCB substrate is within the set range; fourth, it can isolate the positions on the PCB substrate that do not need to be printed, effectively playing a role in isolation and protection; fifth, it improves the efficiency of embedding capacitors and resistors on circuit boards and reduces costs.

[0015] The above-described embodiments are merely preferred embodiments of the present invention, and are described in a relatively specific and detailed manner. However, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. Therefore, all equivalent transformations and modifications made within the scope of the claims of the present invention should be covered by the claims of the present invention.

Claims

1. A method for manufacturing a heat-resistant protective film with embedded capacitance, characterized in that, The embedded capacitor heat-resistant protective film includes, from top to bottom, a base film layer (10) that provides support and maintains dimensional stability, an acrylic adhesive layer (20) that provides adhesion, and a release film layer (30) that provides release protection; the acrylic adhesive layer (20) includes the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent, and 0.4-0.6 parts of epoxy accelerator; the manufacturing method of the embedded capacitor heat-resistant protective film includes the following steps: Step 1: Weigh 18-22 parts of epoxy resin and an equal amount of solvent by weight, mix and dissolve to prepare a 50% solution for later use. Step 2: Weigh 100 parts of acrylic pressure-sensitive adhesive by weight, add the acrylic pressure-sensitive adhesive to the solution prepared in Step 1, then add 30-40 parts of ethanol and 35-45 parts of solvent, and stir to disperse evenly. Step 3: Add 0.4 to 0.6 parts of epoxy curing agent and stir to disperse evenly; Step 4: Add 0.9 to 1.1 parts of epoxy reactive toughening agent and stir to disperse evenly; Step 5: Add 0.4 to 0.6 parts of epoxy accelerator and stir to disperse evenly; Step 6: After filtering with a filter screen, obtain the acrylic adhesive solution and set aside for later use; Step 7: Apply the acrylic adhesive solution from step 6 onto the base film layer (10), and then cure and dry it to obtain the acrylic adhesive layer (20) set on the base film layer (10). During curing and drying, the temperature is controlled at 140℃~160℃ and the time is maintained at 0.5~2 minutes. Step 8: Lay a release film layer (30) onto the acrylic adhesive layer (20); Step 9: Baking and curing, cooling and unloading yields the embedded thermal insulation protective film. During baking and curing, the temperature is controlled at 70℃~90℃ and the time is maintained at 40~60 hours.

2. The method for manufacturing the embedded capacitor and embedded thermal insulation protective film according to claim 1, characterized in that: In steps 1 and 2, the solvent is ethyl acetate.

3. The method for manufacturing the embedded capacitor and embedded thermal insulation protective film according to claim 1, characterized in that: The epoxy curing agent is polyetheramine; the epoxy active toughening agent is polypropylene glycol diglycidyl ester; and the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

4. A heat-resistant protective film with embedded capacitance, characterized in that: It includes a base film layer (10) that provides support and maintains dimensional stability, an acrylic adhesive layer (20) that provides adhesion, and a release film layer (30) that provides release protection, arranged sequentially from top to bottom. The acrylic adhesive layer (20) comprises the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent and 0.4-0.6 parts of epoxy accelerator.

5. The method for manufacturing the embedded capacitor and embedded thermal insulation protective film according to claim 4, characterized in that: The solvent is ethyl acetate, and the amount of ethyl acetate is 53 to 67 parts by mass; the epoxy curing agent is polyetheramine, the epoxy active toughening agent is polypropylene glycol diglycidyl ester, and the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

6. A method for manufacturing a circuit board with embedded capacitors and resistors, characterized in that, Includes the following steps: Step A, applying the protective film: The embedded capacitor and thermal resist protective film includes a base film layer (10) that provides support and maintains dimensional stability, an acrylic adhesive layer (20) that provides adhesion, and a release film layer (30) that provides release protection, arranged sequentially from top to bottom; the embedded capacitor and thermal resist protective film is cut to the same size as the PCB main substrate (91), and then the release film layer (30) of the embedded capacitor and thermal resist protective film is peeled off, and then the acrylic adhesive layer (20) of the embedded capacitor and thermal resist protective film is applied to the upper and lower surfaces of the PCB main substrate (91) respectively; Step B, mechanical drilling: Drill through holes on the PCB main substrate (91) on which the embedded capacitor and thermal insulation protective film is pasted on the upper and lower sides. The number of through holes is the same as the number of electronic components to be embedded. The electronic components to be embedded include capacitors and / or resistors to be embedded. Step C, Printing: Fill the corresponding through holes drilled in Step B with each electronic component using the printing method; Step D, Curing: The electronic components are cured in the through holes of the PCB main substrate (91) by baking according to the curing conditions of the electronic components. Step E, peeling off the film: After the electronic components are cured, peel off the acrylic adhesive layer (20) and the base film layer (10) of the embedded capacitor and embedded thermal resist protective film on the upper and lower sides of the PCB main substrate (91). Step F, stacking: The first upper PCB substrate (92), the second upper PCB substrate (94), the first lower PCB substrate (93) and the second lower PCB substrate (95) are pressed together with the main PCB substrate (91) to obtain a buried capacitor and buried resistor circuit board, wherein the second upper PCB substrate (94), the first upper PCB substrate (92), the main PCB substrate (91), the first lower PCB substrate (93) and the second lower PCB substrate (95) are sequentially placed close together from top to bottom.

7. The method for manufacturing an embedded capacitor-resistor circuit board according to claim 6, characterized in that: In step A, after the acrylic adhesive layer (20) of the embedded capacitor and embedded thermal resist protective film is pasted on the upper and lower sides of the PCB main substrate (91), it is placed in a high-pressure press and pressed for a certain time at a certain temperature, so that the acrylic adhesive layer (20) of the embedded capacitor and embedded thermal resist protective film is pasted together with the PCB main substrate (91).

8. The method for manufacturing a buried capacitor and buried resistor circuit board according to claim 6, characterized in that: The acrylic adhesive layer (20) comprises the following raw materials in parts by weight: 100 parts of acrylate pressure-sensitive adhesive, 18-22 parts of epoxy resin, a certain amount of solvent, 30-40 parts of ethanol, 0.4-0.6 parts of epoxy curing agent, 0.9-1.1 parts of epoxy active toughening agent and 0.4-0.6 parts of epoxy accelerator.

9. The method for manufacturing a buried capacitor and buried resistor circuit board according to claim 8, characterized in that: The solvent is ethyl acetate, and the amount of ethyl acetate is 53 to 67 parts by mass; the epoxy curing agent is polyetheramine, the epoxy active toughening agent is polypropylene glycol diglycidyl ester, and the epoxy accelerator is 2,4,6-tris(dimethylaminomethyl)phenol.

10. The method for manufacturing an embedded capacitor-resistor circuit board according to any one of claims 6 to 9, characterized in that: The total thickness of the base film layer (10) and the acrylic adhesive layer (20) is equal to the set height value of the electronic component above the upper or lower surface of the PCB main substrate (91), so that in step C, the top surface of each electronic component is flush with the upper surface of the base film layer (10) of the embedded capacitor and embedded thermal resist protective film on the upper surface of the PCB main substrate (91), and the bottom surface of each electronic component is flush with the lower surface of the base film layer (10) of the embedded capacitor and embedded thermal resist protective film on the lower surface of the PCB main substrate (91).

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