Circuit board, preparation method of circuit board and display device

Abstract

The invention relates to a circuit board, a preparation method of the circuit board and a display device, and the circuit board comprises a circuit board body; the component structure is arranged on the surface of one side of the circuit board body; the protection layer is located on the surface of the side, provided with the component structure, of the circuit board body, the protection layer comprises a first protection part and a second protection part, the first protection part forms a containing cavity at least attached to the circumferential edge of the component structure, and the second protection part is arranged in the circumferential direction of the first protection part and connected with the circumferential edge of the first protection part; the component structure is located in the containing cavity, and the second protection part is attached to the surface of the circuit board body in a sealed mode. According to the circuit board provided by the invention, the protective layer is formed in advance before being attached, and the protective layer has no internal stress, so that the conditions of virtual attachment and tilting can be effectively prevented, and the sealing performance is improved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a circuit board, a method for preparing the circuit board, and a display device. Background Art

[0002] This section merely provides background information related to the present disclosure and is not necessarily prior art.

[0003] The components used on conventional FPC (Flexible Printed Circuit) are usually very small resistors and capacitors. These tiny devices are soldered in a high-temperature soldering furnace through the SMD method so that the solder can firmly fix the device's solder feet, and then they are glued for protection. Usually, glue protection will fully wrap smaller devices, and for slightly larger devices, glue protection is usually only applied to the solder feet.

[0004] If the FPC device area is only protected by glue, due to the influence of glue fluidity, some positions may have defects such as glue voids and missing. When doing salt spray reliability, salt spray water vapor can invade these defects and cause salt spray corrosion. Usually, a protective film is pasted on the module end. This protective film can not only play the role of electromagnetic shielding, but also to a certain extent fully cover the device area to form a sealed space to prevent salt spray water vapor from entering and corroding the device solder feet. It forms a double insurance with the glue wrapping the solder feet, greatly reducing the risk of salt spray water vapor corroding the solder feet.

[0005] However, even the above-mentioned double insurance is not perfect. Since the protective film is pressed against the device under the action of external force, the protective film is deformed from a flat film layer under the action of pressure to better adhere to the outside of the device of the flexible circuit board. However, after the protective film is attached to the outer surface of the device, the protective film itself is stressed due to the deformation of the protective film under the action of mechanical force. Some areas of the protective film elastically recover under the action of stress, resulting in false adhesion, warping, etc., and no local sealed space is formed. After the salt spray and water vapor invade, they crystallize and deposit in the device area, and then superimposed with the missing glue holes, it is easier to form salt spray and then corrode the solder joints. Summary of the invention

[0006] The purpose of the present invention is to at least solve the problem that the existing protective film is falsely attached or warped, resulting in poor sealing of the components of the flexible circuit board. This purpose is achieved through the following technical solutions:

[0007] According to a first aspect of the present invention, a circuit board body is proposed; a component structure is arranged on one side surface of the circuit board body; a protective layer is located on the side surface of the circuit board body on which the component structure is arranged, the protective layer includes a first protective portion and a second protective portion, the first protective portion forms a accommodating cavity that is at least in contact with the circumferential edge of the component structure, the second protective portion is arranged along the circumference of the first protective portion and connected to the circumferential edge of the first protective portion, the component structure is located in the accommodating cavity, and the second protective portion is sealingly attached to the surface of the circuit board body.

[0008] According to the circuit board proposed by the present invention, a receiving cavity is first formed on the protective layer, so that the components on the circuit board correspond to the receiving cavity, and then the protective layer is attached to the flexible circuit board, the components are accommodated in the receiving cavity, and the second protective part is attached to the upper surface of the circuit board, so that the components are sealed in the receiving cavity. Since the protective layer is pre-formed before attachment, the protective layer has no internal stress, which can effectively prevent false attachment and warping, and improve the sealing performance.

[0009] In addition, the circuit board according to the present invention may also have the following additional technical features:

[0010] In some embodiments of the present invention, the protective layer includes a protective film, and the portion of the protective film corresponding to the first protective part is deformed in a direction away from the circuit board body to form the first protective part, and the second protective part is sealingly attached to the surface of the circuit board body arranged along the circumference of the component structure.

[0011] In some embodiments of the present invention, a protective material is further included, and the protective material forms the protective layer on the surface of the circuit board body and the surface of the component structure through a film forming process. The protective material film layer formed on the surface of the component structure forms the first protective part, and the protective material film layer formed on the surface of the circuit board body arranged along the circumference of the component structure forms the second protective part.

[0012] In some embodiments of the present invention, the component structure includes a component body and a colloid part, the pins of the component body are connected to the circuit board body by welding, and the colloid part wraps at least a portion of the pins of the component body.

[0013] According to a second aspect of the present invention, there is provided a method for preparing a circuit board, the circuit board comprising a circuit board body and a component structure disposed on a surface of one side of the circuit board body, the method comprising:

[0014] A protective layer is formed on the surface of one side of the circuit board body where the component structure is arranged, the protective layer includes a first protective portion and a second protective portion, the first protective portion forms a receiving cavity which is at least in contact with the circumferential edge of the component structure, the second protective portion is arranged along the circumference of the first protective portion and connected to the circumferential edge of the first protective portion, the component structure is located in the receiving cavity, and the second protective portion is sealingly attached to the surface of the circuit board body.

[0015] In some embodiments of the present invention, the protective layer is formed on the surface of one side of the circuit board body where the component structure is arranged, comprising: providing the protective film and a preforming device, wherein the adsorption surface of the preforming device is provided with an adsorption groove and a plane portion arranged along the circumference of the adsorption groove; utilizing the adsorption surface of the preforming device to adsorb the protective film so that the protective film forms a preset shape matching the adsorption surface, the portion of the protective film corresponding to the adsorption groove forms the first protective portion, and the portion corresponding to the plane portion forms the second protective portion; the preforming device carries the protective film and adheres the protective film to the surface of the circuit board body, so that the component structure is located in the accommodating cavity, and under the adsorption action, the second protective portion is sealingly adhered to the surface of the circuit board body arranged along the circumference of the component structure.

[0016] In some embodiments of the present invention, the method further comprises: heating the protective membrane to a preset temperature to eliminate stress of the protective membrane.

[0017] In some embodiments of the present invention, the protective layer is formed on the surface of the side of the circuit board body where the component structure is arranged, comprising: providing a shielding workpiece, and arranging the shielding workpiece on the surface of the circuit board body facing the component structure, the shielding workpiece has a hollow, the component structure is located in the hollow, and a preset gap is arranged between the circumferential edge of the component structure and the hollow boundary; a film forming process is adopted to form a protective material on the surface of the component structure and in the preset gap to form the protective layer, the protective layer formed on the surface of the component structure forms the first protective part, and the protective material film layer formed in the preset gap forms the second protective part.

[0018] In some embodiments of the present invention, a film forming process is used to form a protective material on the surface of the component structure and the preset gap to form the protective layer, including: using a deposition process to deposit the protective material on the surface of the component structure and the preset gap to form the protective layer.

[0019] In some embodiments of the present invention, the protective layer is formed by forming a protective material on the surface of the component structure and the preset gap using a film forming process, including: forming the protective layer by coating the protective material on the surface of the component structure and the preset gap using a coating process.

[0020] According to a third aspect of the present invention, a display device is provided, comprising a circuit board, wherein the circuit board is the circuit board described in any one of the technical solutions of the first aspect; or, the circuit board is manufactured by the method for manufacturing a circuit board described in any one of the technical solutions of the second aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference numerals are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0022] Figure 1 A schematic flow chart of a method for preparing a flexible circuit board according to some embodiments of the present invention is shown;

[0023] Figure 2 A partial schematic diagram of a method for preparing a flexible circuit board according to some embodiments of the present invention is shown;

[0024] Figure 3 A schematic diagram of the structure of a flexible circuit board before glue dispensing in a first viewing angle in some embodiments of the present invention is shown;

[0025] Figure 4 A schematic diagram of the structure of a flexible circuit board before glue dispensing at a second viewing angle in some embodiments of the present invention is shown;

[0026] Figure 5 A schematic diagram of the structure of a flexible circuit board after glue dispensing at a first viewing angle in some embodiments of the present invention is shown;

[0027] Figure 6 A schematic diagram of the structure of a flexible circuit board after glue dispensing at a second viewing angle in some embodiments of the present invention is shown;

[0028] Figure 7 A schematic diagram of the structure of a vacuum suction cup and a protective film in some embodiments of the present invention is shown;

[0029] Figure 8 A schematic diagram showing a structure in which a protective film is preformed into a protective layer by using a vacuum suction cup in some embodiments of the present invention;

[0030] Fig. 9A schematic diagram showing a state in which a protective layer is attached to a flexible circuit board in some embodiments of the present invention;

[0031] Fig.10 A schematic diagram showing a state where a protective layer is attached to a flexible circuit board in some embodiments of the present invention;

[0032] Fig.11 A schematic diagram of a structure for shielding a workpiece in some embodiments of the present invention is shown;

[0033] Fig.12 A schematic diagram showing a structure in which a shielding workpiece is placed on a flexible circuit board at a first viewing angle in some embodiments of the present invention;

[0034] Fig.13 A schematic diagram showing a structure in which a shielding workpiece is placed on a flexible circuit board at a second viewing angle in some embodiments of the present invention;

[0035] Fig.14 A schematic diagram showing a method of spraying a protective material onto a flexible circuit board using a spraying device in some embodiments of the present invention;

[0036] Fig.15 A schematic diagram showing a protective material being sprayed on a flexible circuit board to form a protective layer at a first viewing angle in some embodiments of the present invention;

[0037] Fig.16 A schematic diagram showing a protective material being sprayed onto a flexible circuit board to form a protective layer at a second viewing angle in some embodiments of the present invention.

[0038] The reference numerals are as follows:

[0039] 100, circuit board; 110, circuit board body; 120, component body; 130, colloid part; 20, protective film; 21, protective layer; 211, accommodating cavity; 2111, sub-accommodating cavity; 213, first protective part; 214, second protective part; 30, preforming equipment; 31, adsorption groove; 32, suction channel; 321, adsorption port; 33, plane part; 40, shielding workpiece; 41, hollowing; 50, spraying device. DETAILED DESCRIPTION

[0040] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0041] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0042] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0043] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both above and below orientations.

[0044] According to an embodiment of the present invention, a circuit board is provided. Figure 3 , Figure 4 , Figure 5 , Figure 6 , Fig.10 and Fig.16 As shown, the circuit board includes a circuit board body 110 , a component structure and a protective layer 21 .

[0045] Specifically, the circuit board body 110 is usually made of insulating materials, such as glass fiber reinforced epoxy resin (FR-4), polyimide (PI), etc., and there are pre-designed circuit patterns on the circuit board body 110, and these circuits are formed by etching, electroplating and other processes. The component structure is arranged on one side surface of the circuit board body 110, and the component structure includes electronic components with various functions, such as resistors, capacitors, inductors, diodes, triodes, integrated circuit chips, etc. There are many packaging forms for components, and this embodiment is mainly a patch package of 0201, 0402, 0603 and other devices. The protective layer 21 includes a first protective portion 213 and a second protective portion 214. The first protective portion 213 is formed with a receiving cavity 211 that is at least in contact with the circumferential edge of the component structure. The receiving cavity 211 is pre-designed and manufactured according to the shape and size of the component structure. The shape of the receiving cavity 211 can be various, such as round, square, irregular, etc., to accommodate components of different shapes. For example, for a circular chip, the accommodating cavity 211 is circular, and its diameter is slightly larger than the diameter of the chip, so as to ensure that the chip can be smoothly placed and fit closely with the circumferential edge of the accommodating cavity 211. The second protective portion 214 is arranged along the circumference of the first protective portion 213 and connected to the circumferential edge of the first protective portion 213. The component structure is located in the accommodating cavity 211, and the second protective portion 214 is sealed and attached to the surface of the circuit board body 110. Among them, the second protective portion 214 can be attached to the circuit board body 110 by hot pressing, gluing, etc. The second protective portion 214 fits tightly with the surface of the circuit board body 110 to prevent the intrusion of foreign substances. Through the sealing design of the accommodating cavity 211 of the first protective portion 213 and the second protective portion 214, it can effectively prevent external water vapor, dust, chemicals, etc. from entering the surrounding of the components. Compared with the traditional protection method, this pre-formed protective layer 21 can better fit the components and the circuit board body 110, reducing potential leakage channels. For example, in a humid environment, good sealing can prevent water vapor from condensing on the pins of components, thereby reducing the risk of component damage due to short circuits or corrosion.

[0046] Since the protective layer 21 is pre-formed before lamination and has no internal stress accumulation, it can maintain a flat and tight lamination state when attached to the circuit board body 110. Compared with the existing patch method, which causes problems such as false lamination and warping due to shrinkage, expansion or uneven distribution of materials, the good lamination of the protective layer 21 in this embodiment not only improves the protection effect, but also ensures that the components maintain stable electrical connection during long-term use, reducing failures caused by poor contact. Since the protective layer 21 is pre-formed before lamination, the protective layer 21 has no internal stress, which can effectively prevent false lamination and warping and improve the sealing.

[0047] In some embodiments, the protective layer 21 includes a protective film 20, and the protective film 20 has good flexibility, chemical corrosion resistance and certain mechanical strength. Common materials include high molecular polymer materials such as polyethylene terephthalate (PET), polyimide (PI), or composite materials modified on these basic materials to meet specific protection requirements. In detail, the portion of the protective film 20 corresponding to the first protective portion 213 is deformed in a direction away from the circuit board body 110 to form the first protective portion 213, wherein the deformation process can adopt a thermoforming process, for example, the protective film 20 is placed on a mold with a protrusion corresponding to the shape of the component, and then heated to soften the protective film 20. Under the action of air pressure or mechanical pressure, the film is shaped along the protrusion of the mold to form a shape of a receiving cavity 211 that matches the structural contour of the component; a vacuum blister process can also be used to cover the protective film 20 on a template with air holes and a shape that conforms to the contour of the component, and the film is adsorbed on the vacuum suction cup by a vacuum suction cup to form a corresponding shape of the receiving cavity 211. The second protective portion 214 is arranged along the circumference of the first protective portion 213. When the second protective film 20 is attached to the circuit board body 110, it will fit tightly with the surface of the circuit board body 110 that is arranged along the circumference of the component structure. Since the second protective portion 214 is completely attached along the circumference of the component without any discontinuity, a closed annular sealing area is formed, which further enhances the overall sealing and ensures the reliability of the protective effect.

[0048] In some embodiments, the protective layer 21 also includes a protective material, which forms a protective layer 21 on the surface of the circuit board body 110 and the surface of the component structure through a film forming process. The protective material film layer formed on the surface of the component structure forms a first protective portion 213, and the protective material film layer formed on the surface of the circuit board body 110 arranged along the circumference of the component structure forms a second protective portion 214. Specifically, there are various types of protective materials, which need to be selected according to the specific application scenarios and protection requirements of the circuit board. For example, materials such as acrylic polymers, polyurethanes, and epoxy resins can uniformly form continuous film layers on different surfaces. Another example is a composite material containing nano-metal particles (such as silver and copper nanoparticles), which can not only play a physical protective role after film formation, but also give the circuit board a certain electromagnetic shielding performance; or a material containing fluorocarbon compounds, which has excellent chemical corrosion resistance and hydrophobicity and oleophobicity, and can effectively resist the erosion of external chemicals and stains.

[0049] It should be noted that the film forming process may include a variety of process methods, such as a spraying process, a chemical vapor deposition film forming process, etc.

[0050] In some embodiments, the component structure includes a component body 120 and a colloid part 130, the pins of the component body 120 are welded and connected to the circuit board body 110, and the colloid part 130 wraps at least part of the pins of the component body 120. In this embodiment, the colloid part 130 is formed in the process of dispensing glue to protect the component body 120. First, it is necessary to select an appropriate glue according to the characteristics of the component body 120 carried on the circuit board. For the tiny and precise component body 120, a high-precision, low-viscosity glue is required to ensure that the glue can be accurately attached to the solder pin position, and at the same time, it will not cause additional physical impact or chemical erosion to the component body 120. For example, for some tiny resistors and capacitors such as 0201 that are sensitive to humidity, the glue should also have a certain moisture-proof performance. Secondly, the glue is loaded into the dispensing device. After determining the solder pin coordinate information and the amount of glue dispensed of each component body 120, the solder pin of each component body 120 is dispensed using the dispensing device to form the colloid part 130.

[0051] According to an embodiment of the present invention, a method for preparing a circuit board is proposed. Figure 1 and Figures 7 to 10 As shown, the circuit board includes a circuit board body 110 and a component structure arranged on one side surface of the circuit board body 110. The preparation method includes: forming a protective layer 21 on the side surface of the circuit board body 110 where the component structure is arranged, the protective layer 21 includes a first protective portion 213 and a second protective portion 214, the first protective portion 213 is formed with a accommodating cavity 211 that is at least in contact with the circumferential edge of the component structure, the second protective portion 214 is arranged along the circumference of the first protective portion 213 and connected to the circumferential edge of the first protective portion 213, the component structure is located in the accommodating cavity 211, and the second protective portion 214 is sealingly attached to the surface of the circuit board body 110.

[0052] In the present embodiment, a protective layer 21 is formed on one side surface of the circuit board body 110 where the component structure is provided, and a receiving cavity 211 is formed on the protective layer 21, so that the components on the circuit board correspond to the receiving cavity 211, and the second protective portion 214 is bonded to the upper surface of the circuit board, thereby sealing the components in the receiving cavity 211. Since the protective layer 21 is pre-formed before bonding, the protective layer 21 has no internal stress, which can effectively prevent false bonding and warping, thereby improving the sealing performance.

[0053] According to actual needs, different protective materials can be selected to generate the protective layer 21. In detail, according to the application scenario and protection requirements of the circuit board, as well as different technical means, suitable protective materials can be selected. For example, if the circuit board is used in an environment with strong electromagnetic interference, the protective material must have good electromagnetic shielding performance; if it is used in a high humidity or corrosive environment, the material should have waterproof and anti-corrosion properties. Common protective materials include polymers, composites of metal foil and insulating materials, etc. At the same time, for different molding methods, the morphological structure of the protective material can be either solid or liquid. The common point is that the protective layer 21 formed is a solid structure, and the protective layer 21 can be perfectly fitted with the circuit board.

[0054] In this embodiment, before forming the protective layer 21, it is necessary to ensure that the circuit board 100 is clean. The circuit board 100 can be cleaned to remove dust, oil and other impurities on the surface to prevent these pollutants from affecting the attachment effect of the protective layer 21. When attaching the protective layer 21, a professional patch device or manual operation (for small batches and high precision requirements) can be used to attach the protective layer 21 to the circuit board 100. Among them, the patch device can be an automatic patch machine, which can locate the position of the circuit board 100 through a visual recognition system, and then grab the protective layer 21 by vacuum adsorption or mechanical clamping, and place the protective layer 21 above the circuit board 100, so that the component body 120 is located in the accommodating cavity 211. By continuing to apply uniform pressure, the protective layer 21 is closely attached to the circuit board to ensure sealing.

[0055] In this embodiment, since the protective layer 21 is customized according to the contour of the component body 120 to form the accommodating cavity 211 and then pasted, the fit between the protective layer 21 and the component body 120 is higher than that of the traditional planar pasting method. When the traditional protective film 20 is directly pasted, the pasting process causes the material itself to produce internal stress and other problems, which are prone to false pasting and warping. In the method of the present invention, the protective layer 21 is prepared through precise mold design and molding technology, so that the protective layer 21 forms a stable structure before pasting, without internal stress accumulation, fundamentally preventing the occurrence of false pasting and warping problems, and improving the reliability of protection.

[0056] In addition, the glue point protection is combined with the protection of the protective layer 21 to form a double protection. The glue point provides preliminary protection for the solder pins of the component body 120, which can fix the solder pins and prevent them from loosening during daily use or when subjected to slight mechanical impact; the protective layer 21 covers the component body 120 in all directions as a whole to resist erosion by various environmental factors.

[0057] In some embodiments, the circuit board 100 has a plurality of component bodies 120, and the accommodating cavity 211 includes a plurality of sub-accommodating cavities 2111, and each component body 120 is arranged corresponding to a sub-accommodating cavity 2111. In this embodiment, since the corresponding sub-accommodating cavity 2111 is tailored for each component body 120, the protective layer 21 has a better fit with the plurality of component bodies 120. Compared with the traditional uniform specification protection method, it can effectively avoid the protection loopholes caused by the special shape of individual component bodies 120, and improve the reliability of protection. In harsh environments such as high humidity, dust, and strong salt fog, it is difficult for external impurities such as water vapor, dust, and salt fog to invade, which effectively protects the plurality of component bodies 120 on the circuit board 100 and extends the service life of the circuit board 100.

[0058] It should also be noted that this embodiment can reduce the manufacturing cost of the module factory by moving the tape bonding process forward in advance.

[0059] In some embodiments, please combine Figure 1 , Figure 7 , Figure 8 , Fig. 9 and Fig.10 As shown, forming a protective layer on a surface of a side of a circuit board body where a component structure is arranged includes the following steps:

[0060] Step S101: providing a protective membrane and a preforming device, wherein an adsorption groove and a plane portion 33 arranged along the circumference of the adsorption groove are provided on the adsorption surface of the preforming device;

[0061] Step S102: using the adsorption surface of the preforming device to adsorb the protective film, so that the protective film forms a preset shape matching the adsorption surface, and the portion of the protective film corresponding to the adsorption groove forms the first protective portion 213, and the portion corresponding to the plane portion 33 forms the second protective portion 214;

[0062] Step S103: The preforming device carries a protective film and adheres the protective film to the surface of the circuit board body so that the component structure is located in the accommodating cavity. Under the adsorption effect, the second protective portion 214 is sealed to the surface of the circuit board body arranged along the circumference of the component structure.

[0063] In this embodiment, the preparation method of the protective layer 21 is to preform a planar film layer through a film vacuum adsorption bonding process. Therefore, the protective material can be a solid protective film 20. If the circuit board needs to resist strong electromagnetic interference and high humidity environment, the protective film 20 can be made of a polymer material containing metal fibers or metal coatings. This material has a certain conductivity to achieve electromagnetic shielding and has good waterproof and moisture-proof properties. For example, a protective tape can be used. The protective tape is usually also called IC Cover Tape. The protective tape usually has a three-layer structure: two layers of insulating tape and a layer of conductive cloth in the middle.

[0064] In step S101, according to the morphological structure of the accommodating cavity 211 required for the protective layer 21, an adsorption groove 31 having the same shape as the accommodating cavity 211 can be processed on the adsorption surface of the preforming device 30. The preforming device 30 is provided with a flat portion 33 in the circumferential direction of the adsorption groove, and the adsorption groove 31 corresponds to the accommodating cavity 211 one by one. By making the morphological structure of the adsorption groove 31 the same as the accommodating cavity 211, a mold foundation is provided for the precise shaping of the protective diaphragm 20. When the protective diaphragm 20 is adsorbed, it can be deformed according to a predetermined shape to ensure that the sub-accommodating cavity 2111 on the protective layer 21 finally formed matches the component body 120, thereby improving the pertinence and effectiveness of the protection and avoiding protection loopholes caused by the mismatch between the protective structure and the component body 120.

[0065] In step S102, the selected protective diaphragm 20 is placed above the preforming device 30, and the vacuum system is started to form a negative pressure environment inside the preforming device 30. Under the action of the air pressure difference, the protective diaphragm 20 is tightly adsorbed on the adsorption surface of the preforming device 30 and in the adsorption groove 31. At this time, the protective diaphragm 20 will gradually deform according to the shape of the adsorption groove 31, so that the part of the protective diaphragm 20 corresponding to the adsorption groove forms a first protective portion 213. The part of the protective diaphragm 20 corresponding to the plane portion 33 forms a second protective portion 214. During the adsorption process, the pressure parameters of the vacuum system need to be precisely adjusted according to factors such as the material and thickness of the protective diaphragm 20 to ensure that the protective diaphragm 20 can fit tightly and will not be damaged due to excessive suction. Utilizing the principle of vacuum adsorption, the protective diaphragm 20 can be quickly and evenly attached to the adsorption groove 31, thereby achieving efficient forming of the protective layer 21.

[0066] It is understandable that in other embodiments, hot pressing, stamping and other forming methods may be used instead of the vacuum adsorption forming process, which will not be described in detail here.

[0067] In step S103, before the preforming device carries the protective film formed into a preset shape and prepares for the bonding operation, it is necessary to clean the surface of the circuit board body to ensure that its surface is clean, free of oil, dust and other impurities, so as to ensure that the protective film can be well bonded with the circuit board body and improve the tightness and sealing of the bonding. The cleaning methods commonly used are wiping with a special electronic cleaning agent, or removing organic matter and other impurities that may remain on the surface through a plasma cleaning device. In this step, the preforming device moves the adsorption surface carrying the protective film to the exact position above the circuit board body so that it is accurately aligned with the area where the component structure on the circuit board body is located. After the positioning and alignment is completed, the preforming device begins to slowly descend, so that the protective film gradually approaches the surface of the circuit board body. In this process, the adsorption effect is still maintained to ensure that the protective film will not be displaced or deformed. During the bonding process, the second protective portion 214 on the protective film corresponding to the adsorption surface plane portion 33 will be tightly bonded to the surface of the circuit board body set along the circumference of the component structure under the combined action of the adsorption force and the bonding pressure. The adsorption force helps to "adsorb" the second protective part 214 tightly to the surface of the circuit board, making the fit between the two closer, and the fitting pressure further squeezes the tiny air gap that may exist between the two, prompting a good seal to be formed between the protective diaphragm and the circuit board body. At the same time, since the first protective part 213 corresponding to the adsorption groove has been pre-formed to adapt to the component structure, the component structure smoothly enters the accommodating cavity, so that the entire protective diaphragm can completely cover and seal the components, preventing external impurities such as water vapor, dust, and chemical gases from invading the surrounding of the components from all directions. After confirming that the protective diaphragm and the circuit board body have achieved a good sealing fit, the preforming equipment gradually releases the adsorption effect, allowing the protective diaphragm to be completely transferred and fitted on the circuit board body, and then the adsorption surface of the preforming equipment will separate from the protective diaphragm, completing the entire fitting operation.

[0068] In some embodiments, please combine Figure 1 , Figure 7 , Figure 8 , Fig. 9 and Fig.10 As shown, preparing the protective material into the protective layer 21 by a preset procedure includes the following steps:

[0069] When the protective film 20 is in close contact with the adsorption surface and the adsorption groove 31 , the protective film 20 is heated to a preset temperature to eliminate stress of the protective film 20 .

[0070] In this embodiment, after the protective film 20 has been closely attached to the adsorption surface and the adsorption groove 31 and formed into a preliminary protective layer 21, the protective layer 21 is heated by a heat treatment device. The heat treatment device needs to have a precise temperature control function and can stably increase the temperature according to a preset program.

[0071] The real-time temperature of the protective diaphragm 20 is continuously monitored by using high-precision temperature measuring equipment such as thermocouples or infrared thermometers installed in the heating device near the protective diaphragm 20. When the temperature of the protective layer 21 approaches the preset temperature, the heating device automatically adjusts the power and enters the insulation stage, so that the protective diaphragm 20 is maintained at the preset temperature for a certain period of time to ensure that the stress is fully eliminated. For example, if the preset temperature is 80°C, when the temperature rises to 78°C, the heating device begins to reduce the power so that the protective diaphragm 20 is kept warm within the range of 80°C±2°C for a certain period of time. The specific duration is also determined by the material and thickness of the protective layer 21.

[0072] In this embodiment, when the protective layer 21 is attached to the adsorption groove 31, the internal polymer chain segments of the protective layer 21 are subjected to external forces and deformed by orientation, stretching, etc., thereby generating internal stress. When the protective film 20 is heated to a preset temperature, the molecular motion and thermal expansion principle are used to offset part of the tensile stress generated by processing, so that the stress distribution inside the protective layer 21 is more uniform, thereby achieving the purpose of continuously releasing the internal stress and ultimately eliminating the stress.

[0073] After eliminating stress, the protective layer 21 can fit smoothly and tightly on the target surface, thereby improving the tightness and uniformity of the fit between the protective layer 21 and the circuit board 100, helping to improve the protective performance of the protective layer 21, blocking the intrusion of external impurities such as water vapor, dust, salt spray, and extending the service life of the circuit board 100.

[0074] In some embodiments, please combine Figure 2 , Fig.11 , Fig.12 and Fig.13 As shown, forming a protective layer on a surface of a side of a circuit board body where a component structure is arranged includes the following steps:

[0075] Step S201: providing a shielding workpiece, and placing the shielding workpiece on a surface of the circuit board body facing the component structure, wherein the shielding workpiece is provided with a hollow, wherein the component structure is located in the hollow, and a preset gap is provided between the circumferential edge of the component structure and the hollow boundary;

[0076] Step S202: A protective layer is formed by forming a protective material on the surface of the component structure and in a preset gap using a film forming process. The protective layer formed on the surface of the component structure forms a first protective portion 213 , and the protective material film layer formed in the preset gap forms a second protective portion 214 .

[0077] Among them, there are two ways to form a protective layer by using a film forming process to form a protective material on the surface of the component structure and the preset gap, one is a deposition process, and the other is a coating process.

[0078] In some embodiments, the protective layer 21 is prepared by directly depositing the protective material onto the surface of the component body 120 and preforming the protective material on the surface of the component body 120 through protective material deposition technology. Therefore, the protective material can be a liquid protective material.

[0079] In step S201, the shielding workpiece 40 is a plate-like structure, and the shielding workpiece 40 has good flexibility to adapt to the shape change of the circuit board 100, and should also have chemical stability to avoid chemical reactions with the protective material and the circuit board. For example, the material of the shielding workpiece 40 includes polyethylene terephthalate (PET) film or silicone rubber sheet. PET film has high strength and transparency, which is convenient for observation during operation; silicone rubber sheet has better flexibility and fit. In the process of making the shielding workpiece 40, it is necessary to make a hollow 41 on the shielding workpiece 40 that matches the layout of the component body 120 on the circuit board through precise mold processing or laser cutting and other processes to ensure that the component body 120 can be fully exposed. The covering process needs to be carried out in a dust-free environment, and the operator can use a precise positioning fixture or an optical alignment system to accurately place the shielding workpiece 40 on the circuit board body 110 of the circuit board 100.

[0080] In this step, by means of the hollowing-out 41 design of the shielding workpiece 40, the protective liquid material can be accurately guided to the surface of the component body 120 for deposition, thereby preventing the protective material from being deposited on the area of ​​the circuit board 100 that does not require protection, thus achieving precise positioning of the protection, and helping to reduce production costs and improve protection efficiency. It can also prevent the protective liquid material from contacting key parts such as the circuits and solder joints on the circuit board, thus avoiding problems such as circuit short circuits and poor contact caused by misapplication of the protective material, and ensuring the electrical performance of the circuit board 100.

[0081] In step S202, the circuit board 100 is transferred to the deposition chamber together with the shielding workpiece 40, providing a stable and controllable transition environment for the deposition of the protective material. Interference from external factors such as temperature changes, dust pollution, etc. during the transfer process is avoided, ensuring the smooth progress of the deposition process. By deposition, a uniform and dense protective layer (i.e., the first protective part 213) can be formed on the surface of the component body 120, and another protective layer (i.e., the second protective part 214) can be formed in the preset gap. This protective layer has a strong bonding force with the surface of the component body 120, and can effectively prevent the erosion of the component body 120 by external water vapor, chemicals and mechanical damage, thereby improving the reliability and service life of the component body 120. According to different deposition methods and material selections, the protective layer 21 can be given a variety of properties. For example, the silicon dioxide protective layer 21 prepared by chemical vapor deposition has good insulation and moisture-proof properties; the metal protective layer 21 (such as copper, silver, etc.) prepared by physical vapor deposition can provide electromagnetic shielding function to meet the protection requirements of the circuit board 100 in different application scenarios.

[0082] In other embodiments, please combine Fig.11 , Fig.12 , Fig.13 , Fig.14 , Fig.15 and Fig.16 As shown, the preparation method of the protective layer 21 is obtained by the protective material spraying technology. The circuit board is transferred to the spraying chamber, which can provide a stable, clean and closed environment for the spraying of the protective material. This environment helps to reduce the interference of external factors on the spraying process, such as dust, temperature and humidity changes, etc., thereby improving the quality and uniformity of the protective layer 21. The spraying method enables the protective material to be uniformly deposited on the surface of the component body 120 in the form of fine droplets. By accurately controlling the spraying parameters, accurate protection of component bodies 120 of different shapes, sizes and layouts can be achieved. By spraying, a uniform and dense protective layer (i.e., the first protective part 213) can be formed on the surface of the component body 120, and another protective layer (i.e., the second protective part 214) can be formed in the preset gap. Compared with other deposition methods, spraying is more suitable for component bodies 120 with complex shapes, and can effectively fill the tiny gaps and depressions on the surface of the component body 120, providing more comprehensive protection. By selecting different liquid protective materials and adjusting the spraying parameters, a protective layer 21 with different properties can be obtained. For example, selecting a liquid material with good insulation properties and properly controlling the film thickness can provide excellent electrical insulation protection for the component body 120; selecting a protective material containing metal particles for spraying and undergoing appropriate curing treatment can enable the protective layer 21 to have electromagnetic shielding properties and meet the needs of various complex application scenarios.

[0083] According to the third aspect of the present invention, a display device is also provided, wherein the limiting device includes a circuit board 100, wherein the circuit board 100 is made by the method for making the circuit board 100 in the technical solution of the first aspect. In detail, the display device also includes a display screen, a driver chip, a backlight source, etc. The display screen is responsible for presenting images or text information, the driver chip provides a driving signal for the normal operation of the display screen, and the backlight source provides a light source support behind the liquid crystal display screen, etc., so that the display device can clearly display the content, and the circuit board 100 plays the role of connecting different components, transmitting electrical signals, and realizing electrical functions.

[0084] Since the component body 120 of the circuit board 100 is manufactured by the above-mentioned method for manufacturing the circuit board 100, the circuit board 100 in the display device has the advantages of stable solder joints and good sealing of the protective layer 21. Therefore, whether in an outdoor environment with high temperature and high humidity or in complex working conditions with certain dust and salt, the combination of the protective layer 21 and measures such as glue point protection can effectively block water vapor, dust, salt spray, etc. from invading the interior of the component body 120, preventing the component body 120 from short-circuiting due to moisture, being damaged by corrosion, etc., further enhancing the overall ability of the display device to cope with different environments and improving its reliability.

[0085] According to a fourth aspect of the present invention, a production device is also provided. Figures 6 to 16 As shown, the production equipment is used to prepare the circuit board 100 according to the method for preparing the circuit board 100.

[0086] The production equipment includes a dispensing device (not shown in the figure), a molding device and a patch device. The dispensing device is used to perform dispensing protection on the soldering feet of the component body 120 on the circuit board 100, the molding device is used to prepare the protective material into a protective layer 21 through a preset program, and the patch device is used to apply the protective layer 21 to the circuit board 100.

[0087] The dispensing device includes a glue storage container, a glue supply pump, a dispensing needle, a motion control system, and a visual recognition system. During the dispensing process, the glue supply pump in the glue storage system transports the glue from the storage container to the dispensing head according to the set pressure and flow rate. The glue waits for the outflow instruction in the dispensing head. When the motion control system moves the dispensing head to the first welding foot position, the dispensing head drips the glue on the surface of the welding foot according to the set opening time and glue flow rate. During the dispensing process, the visual recognition system monitors the dispensing position in real time. If a deviation is found, it will be fed back to the motion control system in time for adjustment. After the dispensing head completes the dispensing of one welding foot, the motion control system drives it to move to the next welding foot position and repeats the above operation until all welding feet are glued.

[0088] The patch device includes a gripping mechanism and a moving mechanism, wherein the gripping mechanism can be a vacuum adsorption gripping mechanism. In the process of attaching the protective layer 21 to the circuit board 100, first, by turning on the vacuum pump, a negative pressure is formed at the adsorption head of the gripping mechanism to firmly adsorb the protective layer 21; then the moving mechanism moves the gripping mechanism with the protective layer 21 to a suitable position above the circuit board 100 according to a pre-set program, and slowly lowers the protective layer 21 to make it contact with the circuit board 100, and applies appropriate pressure to make the protective layer 21 fit tightly on the circuit board 100.

[0089] Among them, the molding device is different according to the selected molding process.

[0090] In some embodiments, the patch device may not be provided. After the protective layer 21 is adsorbed and formed by the preforming equipment 30, the vacuum suction cup continues to maintain the adsorption state and presses the protective layer 21 below the circuit board body 110 of the flexible circuit board. After the protective layer 21 adheres to the flexible circuit board, the adsorption state of the vacuum suction cup is stopped, and the protective layer 21 is separated from the preforming equipment 30, and finally the coating work of the protective layer 21 is completed.

[0091] When the preparation method of the protective layer 21 is through a laminating vacuum adsorption bonding process, the molding device includes a preforming device 30 and a heat treatment device. The adsorption surface of the preforming device 30 is formed with an adsorption groove 31, and a plurality of suction channels 32 are provided inside the preforming device 30. The plurality of suction channels 32 respectively form a plurality of adsorption ports 321 on the adsorption surface and the inner wall of the adsorption groove 31. The preforming process of the protective layer 21 is as follows: the selected protective diaphragm 20 is placed above the preforming device 30, and the vacuum system is started to form a negative pressure environment inside the preforming device 30. Under the action of the air pressure difference, the protective diaphragm 20 is tightly adsorbed on the adsorption surface of the suction cup and in the adsorption groove 31. At this time, the protective diaphragm 20 will gradually deform according to the shape of the adsorption groove 31. For example, for the tiny pin groove part in the adsorption groove 31, the protective diaphragm 20 will be accurately pressed in to form a concave structure that matches the pin contour. The heat treatment device is disposed at one side of the preforming equipment 30 , and is used to heat the protective film 20 to a preset temperature to eliminate the internal stress of the protective layer 21 .

[0092] If the preparation method of the protective layer 21 is through protective material deposition technology, the molding device includes a deposition device, and the deposition device has a deposition chamber. Before the protective material is deposited and molded, the shielding workpiece 40 needs to be covered on the circuit board 100 and the component body 120 needs to be exposed outside the shielding workpiece 40. After the placement of the shielding workpiece 40 is completed, the circuit board 100 and the shielding workpiece 40 are transferred to the deposition chamber. The deposition source in the deposition device deposits the protective material onto the surface of the component body 120, thereby forming a uniform and dense protective layer 21 on the surface of the component body 120.

[0093] If the preparation method of the protective layer 21 is through the protective material spraying technology, the molding device includes a spraying device 50, and the spraying device 50 has a motion system, a spraying chamber, a paint container, a delivery pipe, a delivery pump and a spray gun. Before the protective material is sprayed and formed, it is also necessary to cover the shielding workpiece 40 on the circuit board 100 and expose the component body 120 outside the shielding workpiece 40. After the placement of the shielding workpiece 40 is completed, the circuit board 100 and the shielding workpiece 40 are transferred to the spraying chamber. The delivery pump delivers the protective material from the paint container to the spray gun through the delivery pipe, and the motion control system drives the spray gun to move according to the preset parameters. The spray gun moves above the circuit board 100 according to the set trajectory, and sprays the spray evenly on the surface of the component body 120. When the preset number of spraying times is completed or the predetermined amount of protective material is reached, the spraying device 50 stops working. After a certain drying or curing treatment, the protective material forms a protective layer 21 on the surface of the component body 120.

[0094] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A circuit board, characterized in that: include: Circuit board body; A component structure is arranged on a side surface of the circuit board body; A protective layer is located on a side surface of the circuit board body on which the component structure is arranged, and the protective layer includes a first protective portion and a second protective portion, the first protective portion forms a receiving cavity that is at least in contact with the circumferential edge of the component structure, the second protective portion is arranged along the circumference of the first protective portion and connected to the circumferential edge of the first protective portion, the component structure is located in the receiving cavity, and the second protective portion is sealingly attached to the surface of the circuit board body.

2. The circuit board according to claim 1, characterized in that: The protective layer includes a protective film, a portion of the protective film corresponding to the first protective part is deformed in a direction away from the circuit board body to form the first protective part, and the second protective part is sealingly attached to a surface of the circuit board body arranged along the circumference of the component structure.

3. The circuit board according to claim 1, characterized in that: It also includes a protective material, which forms the protective layer on the surface of the circuit board body and the surface of the component structure through a film forming process. The protective material film layer formed on the surface of the component structure forms the first protective part, and the protective material film layer formed on the surface of the circuit board body arranged along the circumference of the component structure forms the second protective part.

4. The circuit board according to any one of claims 1 to 3, characterized in that: The component structure comprises a component body and a colloid part, the pins of the component body are connected to the circuit board body by welding, and the colloid part wraps at least a part of the pins of the component body.

5. A method for preparing a circuit board, characterized in that: The circuit board includes a circuit board body and a component structure arranged on a surface of one side of the circuit board body, and the method includes: A protective layer is formed on the surface of one side of the circuit board body where the component structure is arranged, the protective layer includes a first protective portion and a second protective portion, the first protective portion forms a receiving cavity which is at least in contact with the circumferential edge of the component structure, the second protective portion is arranged along the circumference of the first protective portion and connected to the circumferential edge of the first protective portion, the component structure is located in the receiving cavity, and the second protective portion is sealingly attached to the surface of the circuit board body.

6. The method for preparing a circuit board according to claim 5, characterized in that: The step of forming a protective layer on a surface of the circuit board body on one side where the component structure is disposed comprises: Providing the protective membrane and preforming equipment, wherein the adsorption surface of the preforming equipment is provided with an adsorption groove and a plane portion arranged along the circumference of the adsorption groove; Adsorbing the protective film sheet using the adsorption surface of the preforming device so that the protective film sheet forms a preset shape matching the adsorption surface, and the portion of the protective film sheet corresponding to the adsorption groove forms the first protective portion, and the portion corresponding to the plane portion forms the second protective portion; The preforming equipment carries the protective film and adheres the protective film to the surface of the circuit board body, so that the component structure is located in the accommodating cavity. Under the adsorption effect, the second protective part is sealingly adhered to the surface of the circuit board body arranged along the circumference of the component structure.

7. The method for preparing a circuit board according to claim 6, characterized in that: The method further comprises: The protective film is heated to a preset temperature to eliminate the stress of the protective film.

8. The method for preparing a circuit board according to claim 5, characterized in that: The step of forming a protective layer on a surface of the circuit board body on one side where the component structure is disposed comprises: Providing a shielding workpiece, and setting the shielding workpiece on a side surface of the circuit board body facing the component structure, the shielding workpiece is provided with a hollow, the component structure is located in the hollow, and a preset gap is set between the circumferential edge of the component structure and the hollow boundary; The protective layer is formed by forming a protective material on the surface of the component structure and in the preset gap using a film forming process. The protective layer formed on the surface of the component structure forms the first protective part, and the protective material film layer formed in the preset gap forms the second protective part.

9. The method for preparing a circuit board according to claim 8, characterized in that: The protective layer is formed by forming a protective material on the surface of the component structure and the preset gap using a film forming process, including: The protective layer is formed by depositing protective material on the surface of the component structure and the preset gap using a deposition process.

10. The method for preparing a circuit board according to claim 8, characterized in that: The method of forming the protective layer by forming the protective material on the surface of the component structure and the preset gap by using a film forming process includes: The protective layer is formed by coating the protective material on the surface of the component structure and the preset gap using a coating process.

11. A display device, characterized in that: The display device comprises a circuit board, and the circuit board is the circuit board according to any one of claims 1 to 4; or, the circuit board is manufactured by the method for manufacturing a circuit board according to any one of claims 5 to 10.

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