A basalt fiber reinforced CPI resin mobile phone cover plate and a preparation method thereof

Abstract

The application provides a basalt fiber reinforced CPI resin mobile phone cover plate and a preparation method thereof. The basalt fiber reinforced CPI resin mobile phone cover plate comprises a ceramic substrate, an adhesive layer and a basalt fiber reinforced CPI resin layer. The basalt fiber reinforced CPI resin mobile phone cover plate and the preparation method thereof have the advantages of low density, light weight, high strength, good toughness and low cost.

Description

Technical Field

[0001] This invention relates to the field of mobile phone cover technology, and in particular to a mobile phone cover made of basalt fiber reinforced CPI resin and its preparation method. Background Technology

[0002] Currently, mobile phone cover plates are mainly made of plastic, metal, glass, and ceramic materials. Among them, plastic (polycarbonate) cover plates have good overall performance, but their wear resistance, heat dissipation, and feel are poor, and they are prone to aging, so they are mainly used in mid-to-low-end mobile phones. Metal cover plates have advantages such as drop resistance, strong plasticity, and good heat dissipation, and have become the standard for mainstream mobile phones. With the advent of 5G networks and wireless charging, smartphones have increasingly higher requirements for signal transmission. Metal cover plates have a significant signal shielding effect, becoming a key factor restricting their development. Therefore, the material of mobile phone cover plates will inevitably shift from metal cover plates to non-electromagnetic shielding materials such as glass and ceramic. Because ceramic cover plates have better bending strength, hardness, wear resistance, and heat dissipation than glass cover plates, they have become an important choice for mobile phone manufacturers to achieve material differentiation. Currently, the ceramic materials used to make mobile phone cover plates are mainly zirconium oxide, alumina, and silicon carbide, among which zirconium oxide is the most widely used ceramic material in mobile phone cover plates.

[0003] However, ceramic materials have high density and brittleness. To improve the impact resistance of ceramic phone cover plates, ceramic products are often quite thick, resulting in a heavy weight. For example, zirconia ceramic has a relative density (using the density of water at 4°C as a reference) of 6.0, making its products relatively heavy, which has become a major drawback for its use as phone cover plates. Furthermore, heavier products inevitably consume more expensive ceramic powder, leading to increased costs and limiting its use in the phone cover plate field. Summary of the Invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes a mobile phone cover plate made of basalt fiber reinforced CPI resin and its preparation method. The mobile phone cover plate has the advantages of low density, light weight, high strength, good toughness and low cost.

[0005] The present invention proposes a mobile phone cover plate made of basalt fiber reinforced CPI resin, comprising a ceramic substrate, an adhesive layer and a basalt fiber reinforced CPI resin layer.

[0006] In this invention, an adhesive layer and a basalt fiber reinforced CPI resin layer are sequentially disposed on a ceramic substrate to form a mobile phone cover plate. This reduces the amount of ceramic material used, while improving the overall strength and toughness of the mobile phone cover plate due to the high strength and good toughness of the basalt fiber reinforced CPI resin layer. Furthermore, it allows for a reduction in the thickness of the mobile phone cover plate while still meeting strength requirements, thus achieving a thinner and lighter design.

[0007] Preferably, the adhesive layer is formed by coating an alcoholic aqueous solution of a silane coupling agent onto a ceramic substrate and then curing it.

[0008] Preferably, the silane coupling agent is at least one of KH-550, KH-560, KH-570 or KH-580.

[0009] In this invention, to improve the adhesion between the ceramic substrate and the basalt fiber reinforced CPI resin layer, an alcohol-water solution of a silane coupling agent is coated onto the ceramic substrate and cured to form an adhesive layer. As a strong chemical bond is formed between the silane coupling agent and the oxygen-containing groups on the surface of the ceramic substrate, when the basalt fiber cloth pre-impregnated with CPI resin is subsequently applied, the adhesive layer of the silane coupling agent can again form a strong chemical bond with the basalt fiber reinforced CPI resin layer. This enhances the adhesion between the basalt fiber reinforced CPI resin layer and the ceramic substrate, ultimately allowing the basalt fiber reinforced CPI resin layer to adhere better to the ceramic substrate, thereby obtaining a high-performance mobile phone cover.

[0010] Preferably, the basalt fiber reinforced CPI resin layer is formed by hot pressing and curing basalt fiber cloth pre-impregnated with CPI resin solution.

[0011] Preferably, the CPI resin solution is a fluorinated polyimide resin solution;

[0012] Preferably, the fluorinated polyimide resin solution is obtained by copolymerizing fluorinated diamine monomers and non-fluorinated dianhydride monomers or fluorinated dianhydride monomers in an organic solvent;

[0013] Preferably, the fluorinated diamine monomer is at least one of 2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether, 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl, 2,2-bis-(3-amino-4-hydroxyphenyl)hexafluoropropane, or tetrafluorom-phenylenediamine; the dianhydride monomer is at least one of 4,4′-(hexafluoroisopropene)phthalic anhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, dicyclohexyl-3,4,3',4'-tetracarboxylic dianhydride, or pyromellitic dianhydride.

[0014] Preferably, the basalt fiber cloth is further impregnated in an aqueous solution containing hexadecyltrimethylammonium bromide before being pre-impregnated with CPI resin solution.

[0015] In this invention, basalt fiber cloth is first impregnated with an aqueous solution containing hexadecyltrimethylammonium bromide before being pre-impregnated with CPI resin solution. Hexadecyltrimethylammonium bromide then forms intercalation layers in the pores or interlayer gaps on the surface of the basalt fiber cloth, thus being grafted onto the surface of the basalt fiber cloth. The CPI resin solution is a fluorinated polyimide resin solution, containing fluorinated polar groups in its molecular chain. Therefore, when the basalt fiber cloth is pre-impregnated with CPI resin solution, the hexadecyltrimethylammonium bromide grafted onto the surface of the basalt fiber cloth can adsorb the CPI resin solution, thereby ensuring that the CPI resin solution firmly adheres to the surface of the basalt fiber cloth. This ensures the stability of the CPI resin coating in the basalt fiber cloth, improves the flexural and tensile strength of the basalt fiber, and also helps the basalt fiber-reinforced CPI resin layer to better adhere to the ceramic substrate.

[0016] Preferably, the ceramic substrate is at least one of a zirconia ceramic substrate, an alumina ceramic substrate, or a silicon carbide ceramic substrate.

[0017] Preferably, the thickness of the ceramic substrate is 0.1-1 mm, the thickness of the adhesive layer is 5-50 μm, and the thickness of the fiber-reinforced resin layer is 0.1-1 mm.

[0018] This invention also proposes a method for preparing a mobile phone cover plate made of the above-mentioned basalt fiber reinforced CPI resin, comprising the following steps:

[0019] S1. Provide a ceramic matrix;

[0020] S2. An alcohol-water solution of silane coupling agent is coated onto the ceramic substrate, and after curing, an adhesive layer is formed.

[0021] S3. Basalt fiber cloth pre-impregnated with CPI resin is applied to the adhesive layer, and after hot pressing and curing, a basalt fiber reinforced CPI resin layer is formed to obtain the mobile phone cover plate.

[0022] Preferably, in step S2, the weight ratio of silane coupling agent, alcohol, and water in the aqueous alcohol-water solution of the silane coupling agent is 1:2-4:0.1-0.3.

[0023] Preferably, the curing temperature is 80-100℃ and the curing time is 0.5-2h.

[0024] Preferably, in step S3, the pressure of hot pressing curing is 2-5 MPa, the temperature is 200-260℃, and the time is 1-2 h.

[0025] In this invention, the mobile phone cover plate includes a ceramic substrate, an adhesive layer, and a basalt fiber reinforced CPI resin layer. Because the basalt fiber reinforced CPI resin has high strength and good toughness, it can improve the overall strength and toughness of the mobile phone cover plate and also achieve a thinner and lighter design. At the same time, by connecting the basalt fiber reinforced CPI resin layer and the ceramic substrate through the adhesive layer, the bonding strength between the basalt fiber reinforced CPI resin layer and the ceramic matrix can be greatly improved, avoiding the phenomenon of detachment. Detailed Implementation

[0026] The technical solution of the present invention will be described in detail below through specific embodiments. However, it should be clearly stated that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0027] Example 1

[0028] A mobile phone cover plate reinforced with basalt fiber and CPI resin, the preparation method of which includes the following steps:

[0029] (1) Zirconia ceramic is processed into a sheet with a thickness of 0.3 mm to obtain a ceramic substrate;

[0030] (2) Mix silane coupling agent KH-560, anhydrous ethanol and water in a weight ratio of 1:3:0.2 and stir at room temperature for 1 hour. Then, add dilute hydrochloric acid to adjust the pH to 4.5 to obtain an alcohol-water solution of silane coupling agent. Coat the alcohol-water solution of silane coupling agent onto a ceramic substrate and bake at 90°C for 1 hour to form an adhesive layer with a thickness of 30 μm, thus obtaining a ceramic substrate with an adhesive layer.

[0031] (3) Basalt fiber cloth (plain weave, diameter 13μm, surface density 300g / m²) 2 A pretreated basalt fiber cloth (0.15 mm thick) was soaked in a 1 wt% aqueous solution of hexadecyltrimethylammonium bromide, removed, and dried to obtain the pretreated basalt fiber cloth. 2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether was dissolved completely in N-methylpyrrolidone. Under nitrogen protection, an equimolar amount of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 1 wt% of triethylamine (2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether) were added. After stirring and reacting at room temperature for 3 hours, a CPI resin solution with a solid content of 35 wt% was obtained. This CPI resin solution was coated on both sides of the pretreated basalt fiber cloth, heated to 180°C at a heating rate of 10°C / min, and cured for 1 hour. The coating amount of the resin solution was 300 g / m². 2 Basalt fiber cloth pre-impregnated with CPI resin solution was obtained;

[0032] (4) Two layers of basalt fiber cloth pre-impregnated with CPI resin are applied to a ceramic substrate with an adhesive layer and hot-pressed together. The hot-pressing temperature is 230°C and the pressure is 3MPa. After holding for 1.5 hours, a basalt fiber reinforced CPI resin layer with a thickness of 0.35mm is formed. The layer is then cut and shaped to obtain the mobile phone cover plate.

[0033] Example 2

[0034] A mobile phone cover plate reinforced with basalt fiber and CPI resin, the preparation method of which includes the following steps:

[0035] (1) Zirconia ceramic is processed into a sheet with a thickness of 0.3 mm to obtain a ceramic substrate;

[0036] (2) Mix silane coupling agent KH-550, anhydrous ethanol and water in a weight ratio of 1:2:0.3 and stir at room temperature for 1 h. Then, add dilute hydrochloric acid to adjust the pH to 4.5 to obtain an alcohol-water solution of silane coupling agent. Coat the alcohol-water solution of silane coupling agent onto a ceramic substrate and bake at 100°C for 0.5 h to form an adhesive layer with a thickness of 30 μm, thus obtaining a ceramic substrate with an adhesive layer.

[0037] (3) Basalt fiber cloth (plain weave, diameter 13μm, surface density 300g / m²) 2 A pretreated basalt fiber cloth (0.15 mm thick) was soaked in a 1 wt% aqueous solution of hexadecyltrimethylammonium bromide, removed and dried to obtain the pretreated basalt fiber cloth. 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl was dissolved completely in N-methylpyrrolidone, and under nitrogen protection, an equimolar amount of 4,4′-(hexafluoroisopropene)phthalic anhydride and 1 wt% of triethylamine (by weight of 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl) were added. After stirring and reacting at room temperature for 3 hours, a CPI resin solution with a solid content of 35 wt% was obtained. This CPI resin solution was coated on both sides of the pretreated basalt fiber cloth, heated to 200°C at a heating rate of 5°C / min, and cured for 0.5 hours. The coating amount of the resin solution was 300 g / m². 2 Basalt fiber cloth pre-impregnated with CPI resin solution was obtained;

[0038] (4) Two layers of basalt fiber cloth pre-impregnated with CPI resin are applied to a ceramic substrate with an adhesive layer and hot-pressed together. The hot-pressing temperature is 200°C and the pressure is 5MPa. After holding for 2 hours, a basalt fiber reinforced CPI resin layer with a thickness of 0.34mm is formed. The layer is then cut and shaped to obtain the mobile phone cover plate.

[0039] Example 3

[0040] A mobile phone cover plate reinforced with basalt fiber and CPI resin, the preparation method of which includes the following steps:

[0041] (1) Zirconia ceramic is processed into a sheet with a thickness of 0.3 mm to obtain a ceramic substrate;

[0042] (2) Mix silane coupling agent KH-580, anhydrous ethanol and water in a weight ratio of 1:4:0.1 and stir at room temperature for 1 hour. Then, add dilute hydrochloric acid to adjust the pH to 4.5 to obtain an alcohol-water solution of silane coupling agent. Coat the alcohol-water solution of silane coupling agent onto a ceramic substrate and bake at 80°C for 2 hours to form an adhesive layer with a thickness of 30 μm, thus obtaining a ceramic substrate with an adhesive layer.

[0043] (3) Basalt fiber cloth (plain weave, diameter 13μm, surface density 300g / m²) 2 A pretreated basalt fiber cloth (0.15 mm thick) was soaked in a 1 wt% aqueous solution of hexadecyltrimethylammonium bromide. After drying, it was obtained. Tetrafluorom-phenylenediamine was dissolved completely in N-methylpyrrolidone. Under nitrogen protection, an equimolar amount of pyromellitic anhydride and 1 wt% of triethylamine were added. After stirring at room temperature for 3 hours, a CPI resin solution with a solid content of 35 wt% was obtained. This CPI resin solution was coated on both sides of the pretreated basalt fiber cloth and cured for 0.5 hours at a heating rate of 10℃ / min to 160℃. The coating amount of the resin solution was 300 g / m². 2 Basalt fiber cloth pre-impregnated with CPI resin solution was obtained;

[0044] (4) Two layers of basalt fiber cloth pre-impregnated with CPI resin are applied to a ceramic substrate with an adhesive layer and hot-pressed together. The hot-pressing temperature is 260°C and the pressure is 2MPa. After holding for 1 hour, a basalt fiber reinforced CPI resin layer with a thickness of 0.36mm is formed. The layer is then cut and shaped to obtain the mobile phone cover.

[0045] Comparative Example 1

[0046] A mobile phone cover plate reinforced with basalt fiber and CPI resin, the preparation method of which includes the following steps:

[0047] (1) Zirconia ceramic is processed into a sheet with a thickness of 0.3 mm to obtain a ceramic substrate;

[0048] (2) Basalt fiber cloth (plain weave, diameter 13μm, surface density 300g / m²) 2A pretreated basalt fiber cloth (0.15 mm thick) was soaked in a 1 wt% aqueous solution of hexadecyltrimethylammonium bromide, removed, and dried to obtain the pretreated basalt fiber cloth. 2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether was dissolved completely in N-methylpyrrolidone. Under nitrogen protection, an equimolar amount of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 1 wt% of triethylamine (2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether) were added. After stirring and reacting at room temperature for 3 hours, a CPI resin solution with a solid content of 35 wt% was obtained. This CPI resin solution was coated on both sides of the pretreated basalt fiber cloth, heated to 180°C at a heating rate of 10°C / min, and cured for 1 hour. The coating amount of the resin solution was 300 g / m². 2 Basalt fiber cloth pre-impregnated with CPI resin solution was obtained;

[0049] (3) Two layers of basalt fiber cloth pre-impregnated with CPI resin are applied to the ceramic substrate and hot-pressed together. The hot-pressing temperature is 230°C and the pressure is 3MPa. After holding for 1.5 hours, a basalt fiber reinforced CPI resin layer with a thickness of 0.35mm is formed. The layer is then cut and shaped to obtain the mobile phone cover plate.

[0050] Comparative Example 2

[0051] A mobile phone cover plate reinforced with basalt fiber and CPI resin, the preparation method of which includes the following steps:

[0052] (1) Zirconia ceramic is processed into a sheet with a thickness of 0.3 mm to obtain a ceramic substrate;

[0053] (2) Mix silane coupling agent KH-560, anhydrous ethanol and water in a weight ratio of 1:3:0.2 and stir at room temperature for 1 hour. Then, add dilute hydrochloric acid to adjust the pH to 4.5 to obtain an alcohol-water solution of silane coupling agent. Coat the alcohol-water solution of silane coupling agent onto a ceramic substrate and bake at 90°C for 1 hour to form an adhesive layer with a thickness of 30 μm, thus obtaining a ceramic substrate with an adhesive layer.

[0054] (3) Basalt fiber cloth (plain weave, diameter 13μm, surface density 300g / m²) 2A pretreated basalt fiber cloth (0.15 mm thick) was soaked in a 1 wt% aqueous solution of hexadecyltrimethylammonium bromide, removed and dried to obtain a pretreated basalt fiber cloth. 4,4′-diaminodiphenyl ether was dissolved completely in N-methylpyrrolidone, and under nitrogen protection, an equimolar amount of pyromellitic anhydride and 1 wt% of triethylamine (4,4′-diaminodiphenyl ether by mass) were added. After stirring and reacting at room temperature for 3 hours, a CPI resin solution with a solid content of 35 wt% was obtained. This CPI resin solution was coated on both sides of the pretreated basalt fiber cloth, heated to 180°C at a heating rate of 10°C / min, and cured for 1 hour. The coating amount of the resin solution was 300 g / m². 2 Basalt fiber cloth pre-impregnated with CPI resin solution was obtained;

[0055] (4) Two layers of basalt fiber cloth pre-impregnated with CPI resin are applied to a ceramic substrate with an adhesive layer and hot-pressed together. The hot-pressing temperature is 230°C and the pressure is 3MPa. After holding for 1.5 hours, a basalt fiber reinforced CPI resin layer with a thickness of 0.35mm is formed. The layer is then cut and shaped to obtain the mobile phone cover plate.

[0056] Comparative Example 3

[0057] A mobile phone cover plate reinforced with basalt fiber and CPI resin, the preparation method of which includes the following steps:

[0058] (1) Zirconia ceramic is processed into a sheet with a thickness of 0.3 mm to obtain a ceramic substrate;

[0059] (2) Mix silane coupling agent KH-560, anhydrous ethanol and water in a weight ratio of 1:3:0.2 and stir at room temperature for 1 hour. Then, add dilute hydrochloric acid to adjust the pH to 4.5 to obtain an alcohol-water solution of silane coupling agent. Coat the alcohol-water solution of silane coupling agent onto a ceramic substrate and bake at 90°C for 1 hour to form an adhesive layer with a thickness of 30 μm, thus obtaining a ceramic substrate with an adhesive layer.

[0060] (3) 2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether was dissolved completely in N-methylpyrrolidone. Under nitrogen protection, equimolar amounts of 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 1 wt% of triethylamine (based on the mass of 2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether) were added. The mixture was stirred at room temperature for 3 hours to obtain a CPI resin solution with a solid content of 35 wt%. This CPI resin solution was coated onto basalt fiber cloth (plain weave, diameter 13 μm, surface density 300 g / m²). 2 The resin adhesive is applied to both sides (with a thickness of 0.15 mm), heated to 180°C at a heating rate of 10°C / min, and cured for 1 hour. The coating amount of the resin adhesive is 300 g / m². 2Basalt fiber cloth pre-impregnated with CPI resin solution was obtained;

[0061] (4) Two layers of basalt fiber cloth pre-impregnated with CPI resin are applied to a ceramic substrate with an adhesive layer and hot-pressed together. The hot-pressing temperature is 230°C and the pressure is 3MPa. After holding for 1.5 hours, a basalt fiber reinforced CPI resin layer with a thickness of 0.35mm is formed. The layer is then cut and shaped to obtain the mobile phone cover plate.

[0062] Weight reduction ratio test: Weigh the mobile phone cover plates described in the examples and comparative examples, as well as the pure ceramic zirconia substrates of the same size and thickness of 0.68mm, and calculate the weight reduction ratio of the mobile phone cover plates described in the examples and comparative examples relative to the pure ceramic zirconia substrates of the same size and thickness of 0.68mm.

[0063] Impact resistance test: A 30g steel ball was dropped from a height of 20cm to impact the mobile phone cover plate described in the embodiment and the comparative example, once at each height, each time increasing by 5cm, until cracks appeared on the ceramic surface;

[0064] Temperature and humidity resistance test: The mobile phone cover plates described in the examples and comparative examples were placed in an environment with a temperature of 75°C and a humidity of 95% for 168 hours, and the interface of the mobile phone cover plates was observed to see if there was any peeling phenomenon.

[0065] The results are shown in Table 1 below.

[0066] Table 1. Performance test results of the mobile phone cover plates described in the embodiments and comparative examples.

[0067]

[0068] As can be seen from the table above, the mobile phone cover plate described in the embodiments of the present invention has improved impact performance to varying degrees compared with the comparative example, and the fiber-reinforced resin layer and the ceramic matrix have a better degree of bonding.

[0069] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A mobile phone cover plate made of basalt fiber reinforced CPI resin, characterized in that, Includes a ceramic substrate, an adhesive layer, and a basalt fiber reinforced CPI resin layer; The adhesive layer is formed by coating an alcoholic aqueous solution of a silane coupling agent onto a ceramic substrate and then curing it; the silane coupling agent is at least one of KH-550, KH-560, KH-570 or KH-580. The basalt fiber reinforced CPI resin layer is formed by hot pressing and curing basalt fiber cloth pre-impregnated with CPI resin solution. The CPI resin solution is a fluorinated polyimide resin solution; the fluorinated polyimide resin solution is obtained by copolymerizing a fluorinated diamine monomer and a non-fluorinated dianhydride monomer or a fluorinated dianhydride monomer in an organic solvent. The basalt fiber cloth is further impregnated in an aqueous solution containing hexadecyltrimethylammonium bromide before being pre-impregnated with CPI resin solution.

2. The mobile phone cover plate made of basalt fiber reinforced CPI resin according to claim 1, characterized in that, The fluorinated diamine monomer is at least one of 2,2′-bis(trifluoromethyl)-4,4′-diaminophenyl ether, 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl, 2,2-bis-(3-amino-4-hydroxyphenyl)hexafluoropropane, or tetrafluorom-phenylenediamine; the dianhydride monomer is at least one of 4,4′-(hexafluoroisopropene)phthalic anhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, dicyclohexyl-3,4,3',4'-tetracarboxylic dianhydride, or pyromellitic dianhydride.

3. The mobile phone cover plate made of basalt fiber reinforced CPI resin according to claim 1 or 2, characterized in that, The ceramic substrate is at least one of zirconia ceramic substrate, alumina ceramic substrate, or silicon carbide ceramic substrate.

4. The mobile phone cover plate made of basalt fiber reinforced CPI resin according to claim 1 or 2, characterized in that, The ceramic substrate has a thickness of 0.1-1 mm, the adhesive layer has a thickness of 5-50 μm, and the basalt fiber reinforced CPI resin layer has a thickness of 0.1-1 mm.

5. A method for preparing a mobile phone cover plate made of basalt fiber reinforced CPI resin according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Provide a ceramic matrix; S2. An alcohol-water solution of silane coupling agent is coated onto the ceramic substrate, and after curing, an adhesive layer is formed. S3. Basalt fiber cloth pre-impregnated with CPI resin is applied to the adhesive layer, and after hot pressing and curing, a basalt fiber reinforced CPI resin layer is formed to obtain the mobile phone cover plate.

6. The method for preparing a mobile phone cover plate made of basalt fiber reinforced CPI resin according to claim 5, characterized in that, In step S2, the weight ratio of silane coupling agent, alcohol, and water in the alcohol-water solution of the silane coupling agent is 1:2-4:0.1-0.

3. The curing temperature is 80-100℃, and the time is 0.5-2h.

7. The method for preparing a mobile phone cover plate of basalt fiber reinforced CPI resin according to claim 5 or 6, characterized in that, In step S3, the pressure for hot pressing curing is 2-5 MPa, the temperature is 200-260℃, and the time is 1-2 hours.

Images