A composite ceramic cover plate and its manufacturing method

Abstract

The present invention provides a composite ceramic cover plate and its manufacturing method, which can adjust the thickness and thickness of the ceramic layer and the thermoplastic layer according to the different requirements for the thickness of the cover plate of electronic products through the bending characteristics of different thicknesses of the ceramic layer. The components are adjusted to meet the requirements of the cover plate of the product, so that the cover plate with a ceramic outer surface is prepared by compounding ceramic materials and thermoplastic materials, which not only makes the outer surface of the cover plate have a ceramic texture, but also improves the hardness of the cover plate , strength, toughness and wear resistance, effectively meeting the needs of thin, high-quality and low-cost electronic product cover plates.

Description

technical field [0001] The invention relates to the field of cover plates, in particular to a composite ceramic cover plate suitable for shells of electronic products such as mobile phones and tablet computers and a manufacturing method thereof. Background technique [0002] As the problem of homogenization of smart phones becomes more and more serious, many users nowadays turn their attention to the appearance of the fuselage. Most of the existing back covers of the fuselage are made of metal products and plastic products, and the color of the metal products is relatively single. Common colors are gold, silver and black. Plastic products are widely used in the mobile phone market due to their plasticity and low price, especially low-end phones. Although the production cost of mobile phones is reduced, the plastic back cover often affects the user experience and cannot To achieve higher quality requirements, its hardness and wear resistance are poor, and it is prone to scrat...

AI Technical Summary

Problems solved by technology

[0002] As the problem of homogenization of smart phones becomes more and more serious, many users nowadays turn their attention to the appearance of the fuselage. Most of the existing back covers of the fuselage are made of metal products and plastic products, and the color of the metal products is relatively single. Common colors are gold, silver and black. Plastic products are widely used in the mobile phone market due to their plasticity and low price, especially low-end phones. Although the production cost of mobile phones is reduced, the plastic back cover often affects the user experience and cannot It meets high quality requirements, but its hardness and wear resistance are poor, and it is prone to scratches and signs of wear, which also leads to serious depreciation of the appearance of the fuselage

[0003] The rear cover of the fuselage can also be made of ceramic and glass. If these four materials are compared: in terms of wear resistance, ceramic>glass>metal>plastic; in terms of brittleness, the plasticity of ceramic is significantly enhanced after material modification, satisfying In the drop test, both plastic and metal have strong plasticity, and glass is the worst; in terms of rigidity, ceramics and glass are the best, with small plastic deformation, and plastic is the worst, with obvious plastic deformation; in terms of electromagnetic shielding, ceramics, plastics And glass has no effect and can be formed in one piece, while metal has a great influence. The upper and lower antennas are inlaid with plastic to release signals, which has an impact on the development of wireless charging technology. Because metal has a shielding effect, it is not suitable for subsequent wireless charging, while plastic Too low-end, the glass is fragile, and the ceramic back cover that does not shield electromagnetic signals is undoubtedly the best choice for wireless charging in the future; in terms of coloring performance, ceramics and plastics can be made into a variety of surface patterns, especially ceramics, coloring The latter is more classic and beautiful, with higher quality, and glass is more difficult. Generally, it needs to be filmed to increase texture, and metal products are prone to paint peeling off. In terms of sensory quality and cost, although ceramics have the highest cost, the sensory quality they bring is also The highest, relatively, although the cost of plastic is the lowest, the sensory quality is also the lowest, and it is used as the back cover, the thickness is thicker, once the plastic is made thinner, it will lead to insufficient strength and wear resistance

[0004] Through a comprehensive comparison of the four materials, it is not difficult to see that ceramics undoubtedly have greater advantages in terms of sensory quality, wear resistance, and electromagnetic shielding. However, due to the high cost of ceramics, related manufacturing This is one of the main reasons why ceramic back covers cannot be promoted.

Due to the high hardness of ceramics, it is difficult to form and process ceramics. It can only be polished a little bit by diamond, and the forming efficiency is low. Only two pieces can be produced per day. This method is extremely inefficient, with serious material waste and low product qualification rate, which directly leads to the inability to reduce the manufacturing cost of the ceramic back cover.

[0005] On the other hand, existing patents also provide a variety of preparation methods for mobile phone ceramic covers. In terms of molding process improvement, patent 201010173564.7 "a method for preparing colored zirconia ceramics" adopts dry pressing molding, and patent 201410036959.0 "a A method for preparing mobile phone parts of various colors from zirconia ceramics” uses injection molding to prepare ceramic mobile phone cases, but dry pressing and injection molding are only suitable for thick parts with a thickness greater than 1mm, and ordinary plastic mobile phone cases are only 0.4mm , these two methods are not suitable for the actual ceramic cover production process, for large-sized, thin-walled mobile phone back cover, these two molding methods are difficult to avoid uneven material density due to uneven molding pressure , the parts are easily deformed and cracked during the sintering process

In terms of improvement of ceramic materials, in the patent 201510309285.1 "a preparation method of zirconia ceramic mobile phone back cover", a certain mass fraction of alumina, silica, and titania are doped into zirconia powder to improve the ceramics. However, through CNC processing, the processing process is still relatively difficult, prone to unexpected sudden fractures, which seriously increases production costs; in the patent 201610098697. Adding thermoplastic resin, dispersant, and plasticizer to zirconia nanopowder in "mobile phone case" prepares a mobile phone case of ceramic matrix composite material by injection molding, which does not solve the thickness problem of ceramic matrix injection molding