Material formula and forming process of magnetic control integrated resin plate and automobile sun shield

Abstract

The invention discloses a material formula and a forming process of a magnetic control integrated resin plate and an automobile sun visor, and the magnetic control integrated resin plate comprises the following components in parts by weight: 100 parts of bisphenol A epoxy resin, 4-6 parts of dicyandiamide, 80-120 parts of glass fiber cloth, 25-50 parts of silica powder, 30-60 parts of aluminum hydroxide, 30-60 parts of acetone and 0.1-0.5 part of 2-methylimidazole / urea derivative. Through glue preparation, dipping, drying and semi-curing, cutting and overlapping, hot-press forming and magnetizing treatment, the magnetic control integrated resin plate can be formed at a time on a hydraulic machine and vacuum hot-press mold equipment, preparation can be completed through one hot-press procedure, and the production efficiency is high.

Description

Material formulation, molding process and automotive sun visor of magnetized integrated resin panel Technical Field

[0001] This invention relates to the field of automotive parts manufacturing technology, and in particular to a material formulation, molding process, and automotive sun visor for a magnetically controlled integrated resin plate. Background Technology

[0002] Car sun visors are panels installed above the driver's and passenger's heads to prevent glare from sunlight and headlights at night, thus adjusting the intensity of sunlight on the eyes and preventing traffic accidents. They can be folded down when in use and folded back when not in use.

[0003] As customer needs continue to diversify, some sunshades adopt a magnetic foldable structure. This structure is compact, easy to install, suitable for visual safety requirements, and can meet the needs of sun protection, heat insulation and comfort in different scenarios.

[0004] The magnetic sunshade is equipped with a flip-up soft cover with internal magnetism. Its main body is a resin plate formed by hot pressing the inner lining plate in the middle with the non-woven fabric on both sides to form a magnetically integrated plate. Magnets are embedded in the inner lining plate.

[0005] For example, Chinese patent application number CN202410150509.8, titled "Method for Heat-Sealing Preparation of Magnetic Controlled Soft Cover," discloses: Paragraph

[0005] "To achieve the above objectives, the present invention designs a method for heat-sealing preparation of a magnetic controlled soft cover. The magnetic controlled soft cover includes an inner lining plate, a mirror cover magnet, and a mirror cover fabric. The preparation method includes the following steps: preparing two strip-shaped inner lining plates, one long and one short, the surface of which has snap-fit ​​positions adapted to the mirror cover magnet; according to the number / shape of the snap-fit ​​positions on the surface of the inner lining plate, sequentially hammering in the mirror cover magnet; attaching single-sided adhesive to the snap-fit ​​positions on the surface of the inner lining plate to cover both sides of the mirror cover magnet; cutting two corresponding specifications of non-woven fabric according to the contours of the two inner lining plates for later use; and preparing the two specifications of non-woven fabric..." The fabric is heat-pressed onto both sides of the corresponding inner lining board. The technical solution of "heat-pressing the non-woven fabric with adhesive backing onto the side of the inner lining board corresponding to the positive pole of the mirror cover magnet" involves hammering the magnet into the inner lining board (i.e., the resin board body) in sequence, applying transparent 3M tape to both sides, cutting out non-woven fabric with adhesive backing that has the same outline as the resin board, and then placing the black non-woven fabric (adhesive side up), the resin board, and the white non-woven fabric (adhesive side down) into the resin board hot-pressing pre-molding mold in sequence. The upper and lower non-woven fabrics and the resin board with the magnet are pressed together to obtain the semi-finished magnetic control integrated resin board.

[0006] This traditional process requires multiple steps to prepare a resin board, and each step requires corresponding equipment and tooling. The process is complex, and each additional step increases production costs, which does not meet the requirements for simple and quick production efficiency. Summary of the Invention

[0007] The purpose of this invention is to provide a material formulation and molding process for a magnetically controlled integrated resin board to solve the problems mentioned in the background art.

[0008] To solve the above-mentioned technical problems, the present invention is achieved through the following technical measures: a material formula for a magnetically controlled integrated resin board, characterized in that, by weight ratio, it includes 100 parts of bisphenol A type epoxy resin, 4-6 parts of dicyandiamide, 80-120 parts of glass fiber cloth, 25-50 parts of silica powder, 30-60 parts of aluminum hydroxide, 30-60 parts of acetone, and 0.1-0.5 parts of 2-methylimidazole / urea derivative.

[0009] Furthermore, the bisphenol A type epoxy resin is one of E-51 and E-44. The purpose of this design is that E-51 and E-44 are two common bisphenol A type epoxy resins, which differ in viscosity and epoxy value.

[0010] E-51 has a low viscosity (typically 200-500 mPa·s), good flowability, easy leveling, and strong wettability to substrates; its high epoxy value (approximately 0.51) results in a high degree of reaction after curing and a high heat distortion temperature. Due to its moderate viscosity and high hardness, E-51 is suitable for conventional bonding or electronic encapsulation of metals, ceramics, and glass.

[0011] E-44 has a high viscosity (typically 600-1000 mPa·s), making it less prone to sagging. It also has a low epoxy value (approximately 0.44), resulting in low curing shrinkage, low internal stress, and higher tensile shear strength. Due to its excellent mechanical strength, E-44 is suitable for bonding structural components requiring high shear resistance.

[0012] In practice, a comprehensive judgment should be made based on factors such as viscosity requirements, mechanical strength, curing conditions, and cost.

[0013] Furthermore, the fiberglass cloth is either plain weave fiberglass cloth or satin weave fiberglass cloth. The purpose of this design is that plain weave and satin weave fiberglass cloths differ in their weaving patterns. In plain weave fiberglass cloth, the warp and weft yarns interweave every other yarn, resulting in the most interlacing points, a high number of crimps, and a denser structure. Therefore, it has better strength and abrasion resistance, but less elasticity, a stiffer feel, and poorer luster.

[0014] Satin-weave fiberglass cloth uses a more complex weave, with warp and weft yarns interlacing at least every three yarns, resulting in fewer interlacing points and longer floats. The surface is almost entirely composed of floats in one direction. Therefore, it has long floats, higher density, a smooth and delicate surface, a soft feel, a strong luster, and better elasticity than plain weave cloth, but its abrasion resistance is relatively lower.

[0015] Furthermore, the silicon micropowder is fused silica micropowder. The purpose of this design is to differentiate between silicon micropowder and fused silica micropowder. Fused silica micropowder is produced from natural quartz fragments through a high-temperature melting process. Fused silica micropowder has a lower oil absorption value (approximately 22 g / 100g) and a coefficient of thermal expansion of 0.8‰, making it suitable for high-end electronic applications such as copper-clad laminates for smartphones and tablets, epoxy molding compounds, and adhesives.

[0016] This application also provides a molding process for preparing a magnetically controlled integrated resin plate, characterized by the following steps: 1. Adhesive preparation: Bisphenol A type epoxy resin, silica powder, and aluminum hydroxide are stirred in a mixing tank to disperse them evenly; in another container, dicyandiamide and 2-methylimidazole / urea derivatives are pre-dispersed with acetone, and then added to the previously stirred main resin mixture; finally, the remaining acetone is added, stirred evenly, and filtered to form a uniform adhesive solution.

[0017] 2. Impregnation: The fiberglass cloth is passed through an impregnation tank containing adhesive at a constant speed, and is fully impregnated by the adhesive. The amount of adhesive is controlled by a scraper or roller.

[0018] 3. Drying and semi-curing: The impregnated fiberglass cloth is passed through a drying oven at a temperature controlled at 80-110°C to evaporate the acetone and obtain "prepreg". The solvent is evaporated, allowing the resin to undergo a partial pre-curing reaction, changing the material from a viscous flow state to a semi-cured dry state.

[0019] 4. Cutting and stacking: Cut the large roll of prepreg to the required size. According to the thickness and performance requirements of the design, stack a certain number of layers of prepreg together. Use 40SH magnets, whose thickness is less than that of the resin board body. The stacking order in the mold is as follows: first lay the bottom layer of fiberglass cloth (unimpregnated) + place the required magnets according to the positioning + place the impregnated and cut fiberglass cloth (i.e., single resin board) + lay the top layer of fiberglass cloth (unimpregnated).

[0020] 5. Hot pressing molding: Using a hydraulic press + vacuum hot pressing mold equipment, the stacked materials are fed into the vacuum hot pressing mold, and pressure is applied at 130-150°C and 1.0-1.5 MPa for 60-90 minutes to obtain the resin board body.

[0021] 6. Magnetization treatment: After obtaining the resin board body, magnetize it on a magnetizer.

[0022] Furthermore, the temperature for pre-dispersing dicyandiamide and 2-methylimidazole / urea derivatives with acetone is controlled within the range of 40-50°C.

[0023] Furthermore, the vacuum degree within the vacuum hot pressing mold is ≤1×10⁻ 3 Pa.

[0024] Furthermore, the magnetizer is a 500J-2000J pulse magnetizer; the pole material of the magnetizer clamp is a material with high saturation magnetic induction intensity, the surface of the pole contacting the magnet is flat and smooth, and the pole area is larger than the surface area of ​​the magnet.

[0025] Furthermore, the thickness of the magnet is equal to the thickness of the resin board body minus 0.5mm.

[0026] A car sun visor includes a magnetically controlled integrated resin plate prepared using the above-described molding process.

[0027] Compared with the prior art, the advantages of this invention are: this new material formula and process enable the magnetically controlled integrated resin board to be formed in one step on a hydraulic press + vacuum hot press mold equipment, and the preparation can be completed in one hot pressing process, resulting in high production efficiency. Attached Figure Description

[0028] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0029] In the accompanying drawings: Figure 1 is an exploded view of the magneto-controlled integrated resin plate of the present invention.

[0030] Figure 2 is a plan view of the magnetically controlled soft cover for the sunshade according to the present invention.

[0031] Figure 3 is a cross-sectional view of the magnetically controlled soft cover for the sunshade according to the present invention.

[0032] Explanation of reference numerals in the attached drawings: 1. Fiberglass cloth; 2. Monolithic resin board; 3. Magnet; 4. Magnetically controlled integrated resin board; 5. Knitted fabric. Detailed Implementation

[0033] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0034] Please refer to Figures 1-3 for Example 1.

[0035] The material formulation of the magnetically controlled integrated resin board provided in this embodiment is characterized by comprising, by weight, 100 parts of bisphenol A epoxy resin, 4-6 parts of dicyandiamide, 180-120 parts of glass fiber cloth, 25-50 parts of silica powder, 30-60 parts of aluminum hydroxide, 30-60 parts of acetone, and 0.1-0.5 parts of 2-methylimidazole / urea derivative.

[0036] Bisphenol A type epoxy resin is used as the epoxy resin matrix, which is characterized by strong adhesion, low shrinkage, good electrical properties, and high chemical stability. Before curing, it serves as an adhesive medium; after curing, it forms a three-dimensional network structure that firmly bonds the reinforcing materials and fillers together.

[0037] Fiberglass cloth 1, as a reinforcing material, provides extremely high mechanical strength and dimensional stability, preventing cracking.

[0038] Dicyandiamide acts as an auxiliary material and a curing agent. It reacts rapidly at high temperatures, chemically reacting with epoxy resin to transform it from a liquid or thermoplastic state into a solid three-dimensional network structure.

[0039] Silica powder, as an auxiliary material filler, can reduce costs, decrease curing shrinkage, improve heat resistance, enhance flame retardancy, and adjust viscosity.

[0040] Aluminum hydroxide, as a flame retardant, achieves its flame-retardant effect through decomposition, endothermic reaction, and the release of water vapor, which is key to meeting flame-retardant standards. The dosage can be adjusted according to the target flame-retardant rating.

[0041] Acetone, used as a solvent in auxiliary materials, is used to dissolve the resin and prepare an adhesive solution of appropriate viscosity to facilitate impregnation of the glass fiber cloth 1. The specific amount used is adjusted according to the required operating viscosity and ambient temperature. It completely evaporates during baking and hot pressing.

[0042] 2-Methylimidazole / urea derivatives can lower the curing temperature and accelerate the curing speed. For 1-1.5mm thin boards, adding a small amount of accelerator can ensure smooth curing at 130-150°C, improving production efficiency.

[0043] Furthermore, the bisphenol A type epoxy resin is one of E-51 and E-44. E-51 and E-44 are two common bisphenol A type epoxy resins, which differ in viscosity and epoxy value.

[0044] E-51 has a low viscosity (typically 200-500 mPa·s), good fluidity, easy leveling, and strong wettability to substrates; its high epoxy value (approximately 0.51) results in a high degree of reaction after curing and a high heat distortion temperature.

[0045] E-44 has a high viscosity (typically 600-1000 mPa·s), is not prone to sagging, has a low epoxy value (approximately 0.44), low curing shrinkage, low internal stress, and higher tensile shear strength.

[0046] E-51, with its moderate viscosity and high hardness, is suitable for conventional bonding or electronic packaging of metals, ceramics, and glass.

[0047] Due to its excellent mechanical strength, E-44 is suitable for bonding structural components that require high shear resistance.

[0048] In practice, the selection should be based on a comprehensive assessment of factors such as viscosity requirements, mechanical strength, curing conditions, and cost. In this embodiment, E-51 is selected.

[0049] Furthermore, the fiberglass cloth 1 is one of plain weave fiberglass cloth and satin weave fiberglass cloth. Plain weave fiberglass cloth and satin weave fiberglass cloth differ in their weaving methods. In plain weave fiberglass cloth, the warp and weft yarns interweave every other yarn, resulting in the most interlacing points, a high number of crimps, and a denser structure. Therefore, it has better strength and abrasion resistance, but less elasticity, a harder feel, and poorer luster.

[0050] Satin-weave fiberglass cloth uses a more complex weave, with warp and weft yarns interlacing at least every three yarns, resulting in fewer interlacing points and longer floats. The surface is almost entirely composed of floats in one direction. Therefore, it has long floats, higher density, a smooth and delicate surface, a soft feel, a strong luster, and better elasticity than plain weave cloth, but its abrasion resistance is relatively lower.

[0051] Furthermore, the silicon micropowder is fused silicon micropowder. Fused silicon micropowder is produced from natural quartz fragments through a high-temperature melting process. It has a lower oil absorption value (approximately 22 g / 100g) and a coefficient of thermal expansion of 0.8‰, making it suitable for high-end electronic applications such as copper-clad laminates for smartphones and tablets, epoxy molding compounds, and adhesives.

[0052] In this embodiment, the material composition formula is as follows.

[0053] Epoxy resin E-51: 100 parts; Dicyandiamide: 5 parts; 2-methylimidazole: 0.3 parts; Silica powder (600 mesh): 40 parts; Aluminum hydroxide (800 mesh): 50 parts; Acetone: 50 parts (adjusted according to on-site viscosity); Glass fiber cloth 1: 100 parts. This application also provides a molding process for preparing a magnetically controlled integrated resin board, characterized by the following steps: 1. Adhesive preparation: Bisphenol A type epoxy resin, silica powder, and aluminum hydroxide are stirred in a mixing tank to disperse them evenly; in another container, dicyandiamide and 2-methylimidazole / urea derivatives are pre-dispersed with acetone, then added to the previously stirred main resin mixture, and finally the remaining acetone is added, stirred evenly, and filtered to form a uniform adhesive solution.

[0054] 2. Impregnation: The fiberglass cloth 1 is passed through an impregnation tank containing adhesive solution at a constant speed, and is fully impregnated by the adhesive solution. The amount of adhesive applied is controlled by a scraper or roller.

[0055] 3. Drying and semi-curing: The impregnated glass fiber cloth 1 is passed through a drying oven at a temperature controlled at 80-110°C to evaporate the acetone and obtain "prepreg". The solvent is evaporated, and the resin undergoes a partial pre-curing reaction, so that the material changes from a viscous flow state to a semi-cured dry state.

[0056] 4. Cutting and stacking: Cut the large roll of prepreg to the required size. According to the thickness and performance requirements of the design, stack a certain number of layers of prepreg together. The magnet 3 is a 40SH model, and its thickness is less than the thickness of the resin board body. The stacking order in the mold is as follows: first lay the bottom layer of glass fiber cloth 1 (unimpregnated) + place the required magnet 3 according to the positioning + place the impregnated and cut glass fiber cloth (i.e., single resin board 2) + lay the top layer of glass fiber cloth 1 (unimpregnated).

[0057] 5. Hot pressing molding: Using a hydraulic press + vacuum hot pressing mold equipment, the stacked materials are fed into the vacuum hot pressing mold, and pressure is applied at 130-150°C and 1.0-1.5 MPa for 60-90 minutes to obtain the resin board body.

[0058] 6. Magnetization Process: After obtaining the resin board body, it is magnetized on a magnetizer. Specifically, magnet 3 is made of 40SH material with a thickness of 1mm, so that it can be fully embedded and covered by the 1-1.5mm thick resin board body, ensuring the flatness of the resin board body. This magnet 3 has strong anti-demagnetization ability, and a stronger magnetic field is required to achieve magnetic saturation. Because the high temperature of molding will affect the magnetism of magnet 3, after obtaining the magnetically controlled integrated resin board 4, it is magnetized again on a magnetizer.

[0059] Furthermore, the temperature for pre-dispersing dicyandiamide and 2-methylimidazole / urea derivatives with acetone is controlled within the range of 40-50°C.

[0060] Furthermore, the vacuum degree within the vacuum hot pressing mold is ≤1×10⁻ 3 Pa.

[0061] Furthermore, the magnetizer is a 500J-2000J pulse magnetizer, and the pole material of the magnetizing fixture is a material with high saturation magnetic induction intensity. The surface of the pole contacting the magnet 3 is flat and smooth. The size and shape of the pole match the size of the magnet 3. For thin sheet magnets 3, the pole area can be slightly larger than the magnet 3, but not too much larger, to avoid uneven magnetic field distribution. When the magnet 3 is placed in the fixture, the surface of the pole must achieve tight, gapless contact with the surface of the magnet 3. Any air gap will act like a "resistance," severely weakening the magnetic field reaching the magnet 3.

[0062] Furthermore, the thickness of magnet 3 is equal to the thickness of the resin board body minus 0.5 mm. For 40SH magnet 3, the magnetizing magnetic field strength needs to reach at least 3500 kA / m (approximately 44,000 Oe).

[0063] This embodiment provides a molding process for a magnetically controlled integrated resin board. Please refer to Figure 1. By pre-embedding magnets 3 in the resin board body, the processes of applying adhesive tape and hot-pressing non-woven fabric in the prior art can be eliminated. Then, a knitted fabric 5 with the same outline as the resin board is punched out. The upper glass fiber cloth 1, the single resin board 2, and the lower glass fiber cloth 1 are placed into a hot-pressing pre-molded mold in sequence. The upper and lower glass fiber cloths and the resin board body with pre-embedded magnets 3 (the combination of single resin board 2 and magnets 3 is called the resin board body) are pressed together to obtain a semi-finished magnetically controlled integrated resin board 4 (the combination of the resin board body and the upper and lower glass fiber cloths is called the magnetically controlled integrated resin board 4).

[0064] A car sun visor includes a magnetically controlled integrated resin plate 4 prepared by the above molding process. Referring to Figures 2 and 3, a knitted fabric 5 is then wrapped around the front and back of the magnetically controlled integrated resin plate 4 to form a magnetically controlled soft cover for the sun visor (which contains two magnetically controlled integrated resin plates 4, with the knitted fabric in the middle being hollow, so it can be folded, commonly known as a soft cover).

[0065] The beneficial effects of this invention are as follows: This novel material formula and process enable the magnetically controlled integrated resin board 4 to be formed in one step using a hydraulic press + vacuum hot pressing mold equipment, and the preparation can be completed in one hot pressing process, resulting in high production efficiency.

[0066] In the description of this invention, it should be noted that the terms "vertical," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0067] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0068] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A material formulation for a magnetically controlled integrated resin board, characterized in that: According to the weight ratio, it includes 100 parts of bisphenol A type epoxy resin, 4-6 parts of dicyandiamide, 80-120 parts of glass fiber cloth (1), 25-50 parts of silica powder, 30-60 parts of aluminum hydroxide, 30-60 parts of acetone, and 0.1-0.5 parts of 2-methylimidazole / urea derivatives.

2. The material formulation of the magnetically controlled integrated resin plate according to claim 1, characterized in that: The bisphenol A type epoxy resin is one of E-51 and E-44.

3. The material formulation of the magnetically controlled integrated resin plate according to claim 1, characterized in that: The fiberglass cloth (1) is one of plain weave fiberglass cloth and satin weave fiberglass cloth.

4. The material formulation of the magnetically controlled integrated resin plate according to claim 1, characterized in that: The silicon micropowder used is molten silicon micropowder.

5. A molding process for preparing a magnetically controlled integrated resin plate using the material formulation as described in any one of claims 1 to 4, characterized by comprising the following steps: 5.

1. Adhesive preparation: Bisphenol A type epoxy resin, silica powder, and aluminum hydroxide are stirred in a mixing tank to disperse them evenly; in another container, dicyandiamide and 2-methylimidazole / urea derivatives are pre-dispersed with acetone, then added to the previously stirred main resin mixture, and finally the remaining acetone is added, stirred evenly, and filtered to form a uniform adhesive solution; 5.

2. Impregnation: The glass fiber cloth (1) is passed through an impregnation tank containing adhesive solution at a constant speed and is fully impregnated by the adhesive solution. The amount of adhesive applied is controlled by a scraper or roller. 5.

3. Drying and semi-curing: The impregnated glass fiber cloth (1) is dried in a drying oven at a temperature of 80-110°C to evaporate acetone and obtain "prepreg". The solvent is evaporated to allow the resin to undergo a partial pre-curing reaction, so that the material changes from a viscous flow state to a semi-cured dry state. 5.

4. Cutting and stacking: Cut the large roll of prepreg to the required size. According to the thickness and performance required by the design, stack a certain number of layers of prepreg together. The magnet (3) is a 40SH model, and its thickness is less than the thickness of the resin board body. The stacking order in the mold is as follows: first lay the bottom layer of glass fiber cloth (1) (unimpregnated) + place the required magnet (3) according to the positioning + place the impregnated and cut glass fiber cloth + lay the top layer of glass fiber cloth (1) (unimpregnated). 5.

5. Hot pressing molding: Using a hydraulic press + vacuum hot pressing mold equipment, the stacked materials are fed into the vacuum hot pressing mold, and pressure is applied at 130-150°C and 1.0-1.5 MPa for 60-90 minutes to obtain the resin board body; 5.

6. Magnetization treatment: After obtaining the resin board body, it is magnetized on a magnetizer.

6. The molding process of the magnetically controlled integrated resin plate according to claim 5, characterized in that: The temperature for pre-dispersing dicyandiamide and 2-methylimidazole / urea derivatives with acetone was controlled within the range of 40-50°C.

7. The molding process of the magnetically controlled integrated resin plate according to claim 5, characterized in that: Vacuum degree inside the vacuum hot press mold ≤1×10⁻ 3 Pa.

8. The molding process of the magnetically controlled integrated resin plate according to claim 5, characterized in that: The magnetizer is a 500J-2000J pulse magnetizer; the pole material of the magnetizer clamp is a material with high saturation magnetic induction intensity, the surface of the pole contacting the magnet (3) is flat and smooth, and the pole area is larger than the surface area of ​​the magnet (3).

9. The molding process of the magnetically controlled integrated resin plate according to claim 5, characterized in that: The thickness of the magnet (3) is equal to the thickness of the resin board body - 0.5 mm.

10. A car sun visor, characterized in that: The magnetically controlled integrated resin board (4) is prepared by the molding process of the magnetically controlled integrated resin board as described in any one of claims 5-9.

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